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  • 1.
    Aguilar-Sanchez, Andrea
    et al.
    Stockholm Univ, Div Mat & Environm Chem, Frescativagen 8, S-10691 Stockholm, Sweden..
    Jalvo, Blanca
    Stockholm Univ, Div Mat & Environm Chem, Frescativagen 8, S-10691 Stockholm, Sweden..
    Mautner, Andreas
    Univ Vienna, Fac Chem, Inst Mat Chem & Res, Polymer & Composite Engn PaCE Grp, Wahringer Str 42, A-1090 Vienna, Austria..
    Nameer, Samer
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Pohler, Tiina
    VTT Tech Res Ctr Finland, Solut Nat Resources & Environm, POB 1000, FI-02044 Espoo, Finland..
    Tammelin, Tekla
    VTT Tech Res Ctr Finland, Solut Nat Resources & Environm, POB 1000, FI-02044 Espoo, Finland..
    Mathew, Aji P.
    Stockholm Univ, Div Mat & Environm Chem, Frescativagen 8, S-10691 Stockholm, Sweden..
    Waterborne nanocellulose coatings for improving the antifouling and antibacterial properties of polyethersulfone membranes2021Inngår i: Journal of Membrane Science, ISSN 0376-7388, E-ISSN 1873-3123, Vol. 620, artikkel-id 118842Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This article presents a waterborne nanocellulose coating process to change the surface characteristics and mitigate fouling of commercially available polyethersulfone (PES) microfiltration membranes. An extensive comparative study between nanoporous and nano-textured layers composed of cellulose nanocrystals (CNC) or TEMPO-oxidized cellulose nanofibrils (T-CNF), which were coated on the PES membrane by taking advantage of the electrostatic interactions between the PES substrate, a polyallylamine hydrochloride (PAHC1) anchoring layer, and the nanocellulose functional layer. Coated PES membranes exhibited decreased surface roughness and pore sizes as well as rejection of compounds with a M-w above 150 kDa, while the water permeability and mechanical properties of remained largely unaffected. The coatings improved the wettability as confirmed by a reduction of the contact angle by up to 52% and exhibited a higher negative surface charge compared to the uncoated membranes over a pH range of 4-8. A significant reduction in organic fouling was observed for the coated membranes demonstrated by bovine serum albumin (BSA) adsorption studies on T-CNF and CNC surfaces using Quartz Crystal Microbalance with Dissipation monitoring (QCM-D), UV-vis spectroscopy and FTIR mapping after exposing the membranes to dynamic adsorption of BSA. The T-CNF coating exhibited effective antibacterial action against Escherichia coli (E. coli) attributed to the pH reduction effect induced by the carboxyl groups; while CNC coatings did not show this property. This work demonstrates a simple, green, and easy-to-scale layer-by-layer coating process to tune the membrane rejection and to improve antifouling and antibacterial properties of commercially available membranes.

  • 2.
    Ahrenstedt, Lage
    et al.
    KTH. Cardiovascular Research Unit, University of Cape Town, South Africa.
    Hed, Yvonne
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Hult, Anders
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Zilla, Peter
    Cardiovascular Research Unit, University of Cape Town, South Africa.
    Bezuidenhout, Deon
    Cardiovascular Research Unit, University of Cape Town, South Africa.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Sustained zero-order release of dexamethasone after incorporation into crosslinked PEG-dendrons using click reactions2024Inngår i: Journal of Drug Delivery Science and Technology, ISSN 1773-2247, Vol. 95, artikkel-id 105637Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hydrogel-based localised drug delivery minimises systemic side effects and a linear release profile ensuring a sustained drug release over time, crucial for long-term therapy. The current paper describes the use of the Copper(I)-catalyzed Azide-Alkyne Cycloaddition (CuAAc) to append azidified Dexamethasone (Dex) onto dendrons of first- and second-generation PEGs. Crosslinking with thiolated PEGs using either thiol-acrylate or nucleophilic addition reactions yielded gels containing β-thio-ether ester groups that imparted enhanced hydrolytic susceptibility. In vitro gel degradation was followed gravimetrically and expressed as swelling ratios. Thiol-acrylate crosslinked hydrogels exhibited zero-order Dex release kinetics over 11, 27, and 16 days (G1, G1-star, and G2). Crosslinking the G1-gels by nucleophilic addition also resulted in linear release and the end point was reached in 5 days. Hydrolysis was accounted as the main release mechanism for covalently bound Dex, while physically incorporated Dex showed undefined rapid burst or first-order release, with most of the drug released in the initial 1–3 days. Eluates from covalently bound Dex maintained high activity, whereas Trap-Dex gels lost activity over time, as detected by the upregulation of luciferase expression from a transformed cell line. This novel chemistry combination offers precise drug release control applicable beyond Dex to drugs with suitable nucleophilic groups.

  • 3.
    Alexakis, Alexandros Efraim
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Nanolatexes: a versatile toolbox for cellulose modification2023Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Cellulosic materials are widely used in our everyday lives, ranging from paperand packaging to biomedical applications. However, in most applications, cellulose must coexist with hydrophobic polymers which can be challenging due to its hydrophilic character. This has encouraged the exploration of chemical and physical modifications of cellulose.

    The projects included in this thesis focus on the physical modification of cellulosic materials with tailor-made, highly versatile colloidal nanoparticles synthesized in water, called nanolatexes. Their synthesis is based on the combination of the reversible addition-fragmentation chain transfer (RAFT) polymerization with polymerization-induced self-assembly (PISA). The bridging of these techniques results in the formation of amphiphilic diblock copolymers which self-assemble in water forming a variety of morphologies. Spheres, worms and vesicles with pH-responsive shell polymers were prepared to investigate the parameters that tune these morphological transitions. Less investigated parameters such as the chemical composition of the RAFT agent were studied which resulted in the formation of bimodal nanolatexes with opal-like characteristics in a reproducible manner. 

    A fundamental investigation of the parameters that govern the adsorption of cationically charged nanolatexes onto silica and regenerated TEMPO-oxidized cellulose model surfaces was also performed. The combination of gravimetric and a reflectometric techniques revealed the complexity of that model surface. Both the size and the charge density of the nanolatexes were found to influence their adsorption. The information gained from this study was implemented in the preparation of cellulose nanofibril (CNF)-nanocomposites with low contents of nanolatexes. It was found that when the nanolatex content was below 1 wt% the mechanical profile of the CNF-nanocomposites was improved. 

    Finally, wood-based components were used to replace fossil-based monomers in nanolatexes. They were readily adsorbed onto cellulose filter papers and annealed, thus demonstrating their film formation capacity. Nanolatexes comprised of a wood-based shell polymer have a promising high-end application profile, as showcased by their interactions with Cu(II) ions, where nanolatexes prevented the formation of Cu(II) ion aggregates. 

    The results summarized in this thesis add to the understanding on physical modification of cellulose and are envisaged to further promote the utilization of wood-based monomers in the production of the polymers for high-end applications.

    Fulltekst (pdf)
    fulltext
  • 4.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Ayyachi, Thayanithi
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Mousa, Maryam
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Olsen, Peter
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Biokompositer.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    2-Methoxy-4-Vinylphenol as a Biobased Monomer Precursor for Thermoplastics and Thermoset Polymers2023Inngår i: Polymers, E-ISSN 2073-4360, Vol. 15, nr 9, artikkel-id 2168Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    To address the increasing demand for biobased materials, lignin-derived ferulic acid (FA) is a promising candidate. In this study, an FA-derived styrene-like monomer, referred to as 2-methoxy-4-vinylphenol (MVP), was used as the platform to prepare functional monomers for radical polymerizations. Hydrophobic biobased monomers derived from MVP were polymerized via solution and emulsion polymerization resulting in homo- and copolymers with a wide range of thermal properties, thus showcasing their potential in thermoplastic applications. Moreover, divinylbenzene (DVB)-like monomers were prepared from MVP by varying the aliphatic chain length between the MVP units. These biobased monomers were thermally crosslinked with thiol-bearing reagents to produce thermosets with different crosslinking densities in order to demonstrate their thermosetting applications. The results of this study expand the scope of MVP-derived monomers that can be used in free-radical polymerizations toward the preparation of new biobased and functional materials from lignin.

  • 5.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Engström, Joakim
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Stamm, Arne
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Riazanova, Anastasia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Wallenberg Wood Sci Ctr WWSC, Tekn Ringen 56-58, SE-10044 Stockholm, Sweden..
    Brett, Calvin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, Hamburg, 22603, Germany.
    Roth, Stephan V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. Deutsches Elektronen-Synchrotron (DESY), Notkestrasse 85, Hamburg, 22603, Germany.
    Syrén, Per-Olof
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Fogelström, Linda
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Reid, Michael S.
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Modification of cellulose through physisorption of cationic bio-based nanolatexes - comparing emulsion polymerization and RAFT-mediated polymerization-induced self-assembly2021Inngår i: Green Chemistry, ISSN 1463-9262, E-ISSN 1463-9270, Vol. 23, nr 5, s. 2113-2122Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The polymerization of a bio-based terpene-derived monomer, sobrerol methacrylate (SobMA), was evaluated in the design of polymeric nanoparticles (nanolatexes). Their synthesis was accomplished by using emulsion polymerization, either by free-radical polymerization in the presence of a cationic surfactant or a cationic macroRAFT agent by employing RAFT-mediated polymerization-induced self-assembly (PISA). By tuning the length of the hydrophobic polymer, it was possible to control the nanoparticle size between 70 and 110 nm. The average size of the latexes in both wet and dry state were investigated by microscopy imaging and dynamic light scattering (DLS). Additionally, SobMA was successfully copolymerized with butyl methacrylate (BMA) targeting soft-core nanolatexes. The comparison of the kinetic profile of the cationically stabilized nanolatexes highlighted the differences of both processes. The SobMA-based nanolatexes yielded high T-g similar to 120 degrees C, while the copolymer sample exhibited a lower T-g similar to 50 degrees C, as assessed by Differential Scanning Calorimetry (DSC). Thereafter, the nanolatexes were adsorbed onto cellulose (filter paper), where they were annealed at elevated temperatures to result in polymeric coatings. Their morphologies were analysed by Field Emission Scanning Electron Microscopy (FE-SEM) and compared to a commercial sulfate polystyrene latex (PS latex). By microscopic investigation the film formation mechanism could be unravelled. Water contact angle (CA) measurements verified the transition from a hydrophilic to a hydrophobic surface after film formation had occured. The obtained results are promising for the toolbox of bio-based building blocks, focused on sobrerol-based monomers, to be used in emulsion polymerizations either for tailored PISA-latexes or facile conventional latex formation, in order to replace methyl methacrylate or other high T-g-monomers.

  • 6.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Jerlhagen, Åsa
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Telaretti Leggieri, Rosella
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Eliasson, Adrian
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Benselfelt, Tobias
    School of Materials Science and Engineering Nanyang Technological University 50 Nanyang Avenue Singapore 639798 Singapore.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Modification of CNF‐Networks by the Addition of Small Amounts of Well‐Defined Rigid Cationic Nanolatexes2022Inngår i: Macromolecular Chemistry and Physics, ISSN 1022-1352, E-ISSN 1521-3935, Vol. 224, nr 1, s. 2200249-2200249Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cellulose nanofibril (CNF)-networks are modified by the addition of small amounts (below 10 wt%) of well-defined cationic nanolatexes synthesized through reversible addition–fragmentation chain-transfer-mediated polymerization-induced self-assembly (PISA). Minute amounts of nanolatex inclusions lead to increased tensile and shear moduli, indicating that nanolatexes can act as bridging-points between CNFs. At higher nanolatex content, this stiffening effect is lost, likely due to interactions between nanolatexes leading to plasticization. The influence of nanolatex content and size on interparticle distance is discussed and is used as a tool to understand the effects observed in macroscopic properties. Upon annealing, the stiffening effect is lost due to the softening of the nanolatexes, indicating that the core–shell morphology is a prerequisite for this effect. These systems form a versatile platform to develop fundamental insights into complex condensed colloidal systems, to ultimately aid in the development of new sustainable material concepts.

  • 7.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    pH-Responsive nanolatexes stabilized by statistical copolymers obtained by RAFT-mediated PISAManuskript (preprint) (Annet vitenskapelig)
  • 8.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Riazanova, Anastasia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Bio-based nanolatexes prepared via polymerization-induced self-assembly: targeting heavy metal capturing applicationsManuskript (preprint) (Annet vitenskapelig)
  • 9.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Telaretti Leggieri, Rosella
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Benselfelt, Tobias
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. School of Materials Science and Engineering, Nanyang Technological University, 639798 Singapore, Singapore.
    Nanolatex architectonics: Influence of cationic charge density and size on their adsorption onto surfaces with a 2D or 3D distribution of anionic groups2023Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 634, s. 610-620Artikkel i tidsskrift (Fagfellevurdert)
  • 10.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wilson, Olivia R.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Bimodal nanolatexes prepared via polymerization-induced self-assembly: losing control in a controlled mannerManuskript (preprint) (Annet vitenskapelig)
  • 11.
    Alexakis, Alexandros Efraim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Wilson, Olivia R.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Bimodal nanolatexes prepared via polymerization-induced self-assembly: losing control in a controlled manner2023Inngår i: Polymer Chemistry, ISSN 1759-9954, E-ISSN 1759-9962, Vol. 14, nr 19, s. 2308-2316Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The combination of reversible addition-fragmentation chain-transfer (RAFT) polymerization with polymerization-induced self-assembly (PISA) is known to yield monodisperse nanolatexes. Interestingly, based on the results of the current study, reproducible bimodal nanolatexes were shown to be the result of chain extension of protonated poly(2-dimethylaminoethyl methacrylate) (PDMAEMA) with methyl methacrylate (MMA) in water when aiming for a longer hydrophobic block, for which we provide the first imaging data to our knowledge. The bimodality was found to be induced by the hydrophilic Z-group of the RAFT agent, which has been reported in the literature to be the cause of bimodal molecular weight distributions in RAFT-mediated PISA in emulsion polymerization. Moreover, the advantages of such reproducible bimodal size distribution nanolatexes in coating applications were investigated briefly, underlining the possibilities of their one-pot synthesis. It was found that when bimodal nanolatexes are adsorbed onto cellulose filter paper, the contact angle against water is higher compared to chemically similar monomodal nanolatexes. Also, the morphological arrangement was found to be dependent on the drying protocol. This study aims to expand our understanding on bimodality and the identification of parameters that could promote it on demand to target high-end applications.

  • 12.
    Alipoormazandarani, Niloofar
    et al.
    Lakehead Univ, Dept Chem Engn, Thunder Bay, ON, Canada.;Abo Akad Univ, Lab Nat Mat Technol, Turku, Finland..
    Benselfelt, Tobias
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Wang, Luyao
    Abo Akad Univ, Lab Nat Mat Technol, Turku, Finland..
    Wang, Xiaoju
    Abo Akad Univ, Lab Nat Mat Technol, Turku, Finland..
    Xu, Chunlin
    Abo Akad Univ, Lab Nat Mat Technol, Turku, Finland..
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Willfor, Stefan
    Abo Akad Univ, Lab Nat Mat Technol, Turku, Finland..
    Fatehi, Pedram
    Lakehead Univ, Dept Chem Engn, Thunder Bay, ON, Canada.;Qilu Univ Technol, State Key Lab Biobased Mat & Green Papermaking, Jinan, Shandong, Peoples R China..
    Functional Lignin Nanoparticles with Tunable Size and Surface Properties: Fabrication, Characterization, and Use in Layer-by-Layer Assembly2021Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, nr 22, s. 26308-26317Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lignin is the richest source of renewable aromatics and has immense potential for replacing synthetic chemicals. The limited functionality of lignin is, however, challenging for its potential use, which motivates research for creating advanced functional lignin-derived materials. Here, we present an aqueous-based acid precipitation method for preparing functional lignin nanoparticles (LNPs) from carboxy-methylated or carboxy-pentylated lignin. We observe that the longer grafted side chains of carboxy-pentylated lignin allow for the formation of larger LNPs. The functional nanoparticles have high tolerance against salt and aging time and well-controlled size distribution with R-h <= 60 nm over a pH range of 5-11. We further investigate the layer-by-layer (LbL) assembly of the LNPs and poly(allylamine hydrochloride) (PAH) using a stagnation point adsorption reflectometry (SPAR) and quartz crystal microbalance with dissipation (QCM-D). Results demonstrate that LNPs made of carboxypentylated lignin (i.e., PLNPs with the adsorbed mass of 3.02 mg/m(2)) form a more packed and thicker adlayer onto the PAH surface compared to those made of carboxymethylated lignin (i.e., CLNPs with the adsorbed mass of 2.51 mg/m(2)). The theoretical flux, J, and initial rate of adsorption, (d Gamma/dt)(0), analyses confirm that 22% of PLNPs and 20% of CLNPs arriving at the PAH surface are adsorbed. The present study provides a feasible platform for engineering LNPs with a tunable size and adsorption behavior, which can be adapted in hionanomaterial production.

  • 13.
    Andrén, Oliver C. J.
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Ingverud, Tobias
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Hult, Daniel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Håkansson, Joakim
    Bogestål, Yalda
    Caous, Josefin S.
    Blom, Kristina
    Zhang, Yuning
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Andersson, Therese
    Pedersen, Emma
    Björn, Camilla
    Löwenhielm, Peter
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Antibiotic-Free Cationic Dendritic Hydrogels as Surgical-Site-Infection-Inhibiting Coatings2019Inngår i: Advanced Healthcare Materials, ISSN 2192-2640, E-ISSN 2192-2659, Vol. 8, nr 5Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Abstract A non-toxic hydrolytically fast-degradable antibacterial hydrogel is herein presented to preemptively treat surgical site infections during the first crucial 24 h period without relying on conventional antibiotics. The approach capitalizes on a two-component system that form antibacterial hydrogels within 1 min and consist of i) an amine functional linear-dendritic hybrid based on linear poly(ethylene glycol) and dendritic 2,2-bis(hydroxymethyl)propionic acid, and ii) a di-N-hydroxysuccinimide functional poly(ethylene glycol) cross-linker. Broad spectrum antibacterial effect is achieved by multivalent representation of catatonically charged ?-alanine on the dendritic periphery of the linear dendritic component. The hydrogels can be applied readily in an in vivo setting using a two-component syringe delivery system and the mechanical properties can accurately be tuned in the range equivalent to fat tissue and cartilage (G? = 0.5?8 kPa). The antibacterial effect is demonstrated both in vitro toward a range of relevant bacterial strains and in an in vivo mouse model of surgical site infection.

  • 14.
    Arseneault, Mathieu
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Granskog, Viktor
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Khosravi, Sara
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Heckler, Ilona
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Antunez, Pablo Mesa
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Hult, Daniel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Zhang, Yuning
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    The Dawn of Thiol-Yne Triazine Triones Thermosets as a New Material Platform Suited for Hard Tissue Repair2018Inngår i: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 30, nr 52, artikkel-id 1804966Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The identification of a unique set of advanced materials that can bear extraordinary loads for use in bone and tooth repair will inevitably unlock unlimited opportunities for clinical use. Herein, the design of high-performance thermosets is reported based on triazine-trione (TATO) monomers using light-initiated thiol-yne coupling (TYC) chemistry as a polymerization strategy. In comparison to traditional thiol-ene coupling (TEC) systems, TYC chemistry has yielded highly dense networks with unprecedented mechanical properties. The most promising system notes 4.6 GPa in flexural modulus and 160 MPa in flexural strength, an increase of 84% in modulus and 191% in strength when compared to the corresponding TATO system based on TEC chemistry. Remarkably, the mechanical properties exceed those of polylactide (PLA) and challenge poly(ether ether ketone) PEEK and today's methacrylate-based dental resin composites. All the materials display excellent biocompatibility, in vitro, and are successfully: i) molded into medical devices for fracture repair, and ii) used as bone adhesive for fracture fixation and as tooth fillers with the outstanding bond strength that outperform methacrylate systems used today in dental restoration application. Collectively, a new era of advanced TYC materials is unfolded that can fulfill the preconditions as bone fixating implants and for tooth restorations.

  • 15.
    Arseneault, Mathieu
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Granskog, Viktor
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Khosravi, Sara
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Heckler, Ilona
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Mesa-Antunez, Pablo
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Hult, Daniel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Zhang, Yuning
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Highly crosslinked triazine-trione materials for fracture fixation based on TEC and TYC chemistryManuskript (preprint) (Annet vitenskapelig)
  • 16.
    Asem, Heba
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Design of Functional Polymeric Nanoparticles for Biomedical Applications2020Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Most of the devastating diseases such as cancer are relatively incurable and have high risks of relapse. Therefore, persistent endeavors have been devoted to improve patient survival rate and quality of life. Drug delivery systems (DDS) based on polymeric nanoparticles (PNPs) have been demonstrated to increase the therapeutic index (efficacy/toxicity ratio) of chemotherapeutic agents. This thesis focuses on designing non-toxic and multifunctional biodegradable PNPs from preformed polymers for bioimaging and drug delivery applications. Multifunctional poly(lactide-co-glycolide) (PLGA) NPs were simultaneously loaded with imaging probes, superparamagnetic iron oxide nanoparticles (SPION) and manganese-doped zinc sulfide (Mn:ZnS) quantum dots (QDs), as well as an anti-cancer drug, busulfan (Bu), during the particle formation. The NPs were utilized to enhance magnetic resonance imaging (MRI) in vivo and controlled drug release in vitro (Paper I). Poly(ε-caprolactone) (PCL) was copolymerized with poly(ethylene glycol) (PEG) to achieve stealth property for in vivo purposes. Aluminum phthalocyanine, a photosensitizer and an anti-cancer drug, was encapsulated in the PEG-b-PCL NPs for photodynamic therapy during particle formation. The biodistribution of the prepared nanophotosensitizer showed targeted drug delivery toward lungs, liver and spleen as monitored by the intrinsic fluorescence of the photosensitizer (Paper II). The PEG-b-PCL NPs were loaded with SPION or surface functionalized with VivoTag 680XL fluorochrome and utilized for in vivo multimodal imaging, MRI and fluorescence imaging (Paper III). This thesis also presents stable and engineered PNPs obtained using reversible addition-fragmentation chain transfer (RAFT) mediated polymerization-induced self-assembly (PISA). Hydrophobic agents, nile red (NR) dye or doxorubicin (DOX) drug, were encapsulated in poly(N-[3- (dimethylamino) propyl] methacrylamide)-b-poly(methyl methacrylate) (PDMAPMA-b-PMMA) NPs via one-pot RAFT-mediated PISA in water (Paper IV). The PDMAPMA-b-PMMA NPs showed very monodisperse spheres and core-shell nanostructures. Stable and non-toxic poly(acrylic acid)-b-poly(butyl acrylate) (PAA-b-PBA) NPs, synthesized via RAFTmediated PISA in water, were surface engineered by allyl-functional groups prior to bio-conjugation for targeted drug delivery (Paper V). The engineered NPs retained their colloidal stability and size post-allyl functionalization. DOX was efficiently (90 %) encapsulated in the PAA-bPBA NPs during NPs formation. A controlled release pattern of DOX from PAA-b-PBA NPs was observed over 7 days.

  • 17.
    Asem, Heba
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Zheng, Wenyi
    Division of Experimental Cancer Medicine (ECM), Department of Laboratory Medicine (LABMED), Karolinska Institutet, SE-141 86 Stockholm, Sweden.
    Nilsson, Fritjof
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Zhang, Yuning
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Hedenqvist, Mikael S.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Polymera material.
    Hassan, Moustapha
    Clinical Research Centrum, Department of Stem Cell Transplantation (CAST), Karolinska University Hospital-Huddinge, SE-141 86 Stockholm, Sweden.
    Malmström, Eva
    KTH, Tidigare Institutioner (före 2005), Fiber- och polymerteknologi.
    Functional nano-carriers for drug delivery by surface engineering of polymeric nanoparticles post-PISAManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Engineered polymeric nanoparticles (NPs) have been comprehensively explored as potential platforms for diagnosis and targeted therapy for several diseases including cancer. Herein, we designed functional poly(acrylic acid)-b-poly(butyl acrylate) (PAA-b-PBA) NPs using reversible addition-fragmentation chain-transfer (RAFT)-mediated emulsion polymerization via polymerization-induced self-assembly (PISA). The hydrophilic PAA-macroRAFT, forming a stabilizing shell (i.e. corona), was chain-extended using the hydrophobic monomer n-butyl acrylate (n-BA), resulting in stable, monodisperse and reproducible PAA-b-PBA NPs, typically having a diameter of 130 nm. Two approaches of surface engineering of the PAA-b-PBA NPs post-PISA were explored; a two-step and a one-step approach. In the two-step approach, the hydrophilic NP-shell corona was modified with allyl-groups under mild conditions using allylamine in water which resulted in stable allyl-functional NPs (allyl-NPs) suitable for further bio-conjugation. Their versatility was investigated by the subsequent conjugation of a thiol-functional fluorescent dye (BODIPY-SH) to the allyl-groups using click chemistry, in order to mimic the attachment of a thiol-functional target ligand. The average size and size distribution of the corresponding NPs did not change after BODIPY-conjugation. Neither the NPs nor allyl-NPs showed significant cytotoxicity towards RAW264.7 or MCF-7 cell lines, which indicates their desirable safety profile. A one-step approach to concurrently conjugate allyl-groups and a fluorescent dye (FITC) to the preformed PAA-b-PBA NPs was investigated. The cellular uptake of the FITC-NPs using J774A cells in vitro was found to be time- and concentration-dependent. The anti-cancer drug, doxorubicin, was efficiently (90%) encapsulated into the PAA-b-PBA NPs during NP formation. After a small burst release during the first two hours, a controlled release pattern over 7 days was observed. The present investigation demonstrates a potential method to functionalize polymeric NPs post-PISA to produce targeted drug delivery carriers.

    Fulltekst (pdf)
    fulltext
  • 18.
    Asp, Leif E.
    et al.
    Department of Industrial and Materials Science, Chalmers University of Technology, Gothenburg, SE-412 96, Sweden.
    Bouton, Karl
    Carlstedt, David
    Department of Industrial and Materials Science, Chalmers University of Technology, Gothenburg, SE-412 96, Sweden.
    Duan, Shanghong
    Department of Industrial and Materials Science, Chalmers University of Technology, Gothenburg, SE-412 96, Sweden.
    Harnden, Ross
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Farkostteknik och Solidmekanik.
    Johannisson, Wilhelm
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Farkostteknik och Solidmekanik.
    Johansen, Marcus
    Department of Industrial and Materials Science, Chalmers University of Technology, Gothenburg, SE-412 96, Sweden.
    Johansson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Lindbergh, Göran
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Liu, Fang
    Department of Industrial and Materials Science, Chalmers University of Technology, Gothenburg, SE-412 96, Sweden.
    Peuvot, Kevin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Schneider, Lynn Maria
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Farkostteknik och Solidmekanik.
    Xu, Johanna
    Department of Industrial and Materials Science, Chalmers University of Technology, Gothenburg, SE-412 96, Sweden.
    Zenkert, Dan
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik, Farkostteknik och Solidmekanik.
    A Structural Battery and its Multifunctional Performance2021Inngår i: Advanced Energy & Sustainability Research, E-ISSN 2699-9412, Vol. 2, nr 3, artikkel-id 2000093Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Engineering materials that can store electrical energy in structural load paths can revolutionize lightweight design across transport modes. Stiff and strong batteries that use solid-state electrolytes and resilient electrodes and separators are generally lacking. Herein, a structural battery composite with unprecedented multifunctional performance is demonstrated, featuring an energy density of 24 Wh kg−1 and an elastic modulus of 25 GPa and tensile strength exceeding 300 MPa. The structural battery is made from multifunctional constituents, where reinforcing carbon fibers (CFs) act as electrode and current collector. A structural electrolyte is used for load transfer and ion transport and a glass fiber fabric separates the CF electrode from an aluminum foil-supported lithium–iron–phosphate positive electrode. Equipped with these materials, lighter electrical cars, aircraft, and consumer goods can be pursued.

  • 19.
    Badria, Adel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Click Chemistry: A Promising Tool for Building Hierarchical Structures2022Inngår i: Polymers, E-ISSN 2073-4360, Vol. 14, nr 19, artikkel-id 4077Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The hierarchical structures are utilized at different levels in nature. Moreover, a wide spectrum of nature’s properties (e.g., mechanical, physical and biological properties) has been attributed to this hierarchy. Different reviews have been published to cover the use of click chemistry in building hierarchical structures. However, each one of those reviews focused on a narrow area on this topic, i.e., specific chemical reaction, such as in thiol-ene chemistry, or a specific molecule or compound such as polyhedral oligomeric silsesquioxane, or a certain range of hierarchical structures between the nano to micro range, e.g., nanocrystals. In this review, a frame to connect the dots between the different published works has been demonstrated. This article will not attempt to give an exhaustive review of all the published work in the field, instead the potential of click chemistry to build hierarchical structures of different levels using building blocks of different length scales has been shown through two main approaches. The first is a one-step direct formation of 3D micro/macrometer dimensions structures from Pico dimensions structures (molecules, monomers, etc.). The second approach includes several steps Pico ➔ 0D nano ➔ 1D nano ➔ 2D nano ➔ 3D nano/micro/macro dimensions structures. Another purpose of this review article is to connect between (a) the atomic theory, which covers the atoms and molecules in the picometer dimensions (picoscopic chemistry set); (b) “nano-periodic system” model, which covers different nanobuilding blocks in the nanometers range such as nanoparticles, dendrimers, buckyball, etc. which was developed by Tomalia; and (c) the micro/macrometer dimensions level.

  • 20.
    Badria, Adel
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Hutchinson, Daniel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Sanz del Olmo, Natalia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Acrylate-free tough 3D printable thiol-ene thermosets and composites for biomedical applications2022Inngår i: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 139, nr 43, artikkel-id e53046Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Polymer thermosets and composites based on rigid trizaine-trione (TATO) alkene and thiol monomers show great promise as bone fixation materials and dental composites due to their ability to efficiently crosslink via thiol-ene coupling chemistry into stiff and strong materials. In order to broaden the scope of these materials, a TATO thermoset was optimized for sterolithography (SLA) 3D printing through the addition of either a diluent (PETMP) and photo-absorber (Sudan I), or the addition of a free radical inhibitor (pyrogallol). A 3D printable hydroxyapatite (HA) composite was also formulated by adding a combination of nano-HA and micro-HA particles, which were found to increase the thermal stability and modulus of the material, respectively. The modulus of the printed thermosets containing Sudan I and pyrogallol exceeded any previously published acrylate-free thiol-ene SLA resins, at 1.6 (0.1) and 1.85 (0.06) GPa, respectively. The printed HA composite formulation had a modulus of 2.4 (0.2) GPa. All three formulations showed a comparable resolution to a commercially available SLA resin and were non-toxic toward Raw 264.7 and human dermal fibroblast cells. These results demonstrate the potential of TATO based SLA resins for the construction of strong, fully-customizable, printed implants for biomedical applications.

  • 21.
    Badria, Adel
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. Univ Patras, Dept Mech Engn & Aeronaut, Div Appl Mech Technol Mat & Biomech, Patras, Greece..
    Koutsoukos, Petros G.
    Univ Patras, Dept Chem Engn, Patras Univ Campus, Patras 26504, Greece..
    Mavrilas, Dimosthenis
    Univ Patras, Dept Mech Engn & Aeronaut, Div Appl Mech Technol Mat & Biomech, Patras, Greece..
    Decellularized tissue-engineered heart valves calcification: what do animal and clinical studies tell us?2020Inngår i: Journal of materials science. Materials in medicine, ISSN 0957-4530, E-ISSN 1573-4838, Vol. 31, nr 12, artikkel-id 132Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cardiovascular diseases are the first cause of death worldwide. Among different heart malfunctions, heart valve failure due to calcification is still a challenging problem. While drug-dependent treatment for the early stage calcification could slow down its progression, heart valve replacement is inevitable in the late stages. Currently, heart valve replacements involve mainly two types of substitutes: mechanical and biological heart valves. Despite their significant advantages in restoring the cardiac function, both types of valves suffered from serious drawbacks in the long term. On the one hand, the mechanical one showed non-physiological hemodynamics and the need for the chronic anticoagulation therapy. On the other hand, the biological one showed stenosis and/or regurgitation due to calcification. Nowadays, new promising heart valve substitutes have emerged, known as decellularized tissue-engineered heart valves (dTEHV). Decellularized tissues of different types have been widely tested in bioprosthetic and tissue-engineered valves because of their superior biomechanics, biocompatibility, and biomimetic material composition. Such advantages allow successful cell attachment, growth and function leading finally to a living regenerative valvular tissue in vivo. Yet, there are no comprehensive studies that are covering the performance of dTEHV scaffolds in terms of their efficiency for the calcification problem. In this review article, we sought to answer the question of whether decellularized heart valves calcify or not. Also, which factors make them calcify and which ones lower and/or prevent their calcification. In addition, the review discussed the possible mechanisms for dTEHV calcification in comparison to the calcification in the native and bioprosthetic heart valves. For this purpose, we did a retrospective study for all the published work of decellularized heart valves. Only animal and clinical studies were included in this review. Those animal and clinical studies were further subcategorized into 4 categories for each depending on the effect of decellularization on calcification. Due to the complex nature of calcification in heart valves, other in vitro and in silico studies were not included. Finally, we compared the different results and summed up all the solid findings of whether decellularized heart valves calcify or not. Based on our review, the selection of the proper heart valve tissue sources (no immunological provoking residues), decellularization technique (no damaged exposed residues of the decellularized tissues, no remnants of dead cells, no remnants of decellularizing agents) and implantation techniques (avoiding suturing during the surgical implantation) could provide a perfect anticalcification potential even without in vitro cell seeding or additional scaffold treatment. [GRAPHICS] .

  • 22.
    Benselfelt, Tobias
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Nordenström, Malin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Lindstrom, Stefan B.
    Linkoping Univ, Div Solid Mech, Dept Management & Engn, S-58183 Linkoping, Sweden..
    Wågberg, Lars
    KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation. KTH, Skolan för teknikvetenskap (SCI), Centra, Linné Flow Center, FLOW. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi. KTH Royal Inst Technol, Div Fibre Technol, Dept Fiber & Polymer Technol, Tekn Ringen 56-58, S-10044 Stockholm, Sweden.;KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, Dept Fiber & Polymer Technol, Tekn Ringen 56-58, S-10044 Stockholm, Sweden..
    Explaining the Exceptional Wet Integrity of Transparent Cellulose Nanofibril Films in the Presence of Multivalent Ions-Suitable Substrates for Biointerfaces2019Inngår i: Advanced Materials Interfaces, ISSN 2196-7350, Vol. 6, nr 13, artikkel-id 1900333Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cellulose nanofibrils (CNFs) assemble into water-resilient materials in the presence of multivalent counter-ions. The essential mechanisms behind these assemblies are ion-ion correlation and specific ion effects. A network model shows that the interfibril attraction indirectly influences the wet modulus by a fourth power relationship to the solidity of the network (E-w proportional to phi(4)). Ions that induce both ion-ion correlation and specific ion effects significantly reduce the swelling of the films, and due to the nonlinear relationship dramatically increase the wet modulus. Herein, this network model is used to explain the elastoplastic behavior of wet films of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-oxidized, carboxymethylated, and phosphorylated CNFs in the presence of different counter-ions. The main findings are that the aspect ratio of the CNFs influences the ductility of the assemblies, that the bivalency of phosphorylate ligands probably limits the formation of interfibril complexes with divalent ions, and that a higher charge density increases the friction between fibrils by increasing the short-range attraction from ion-ion correlation and specific ion effects. These findings can be used to rationally design CNF materials for a variety of applications where wet strength, ductility, and transparency are important, such as biomaterials or substrates for bioelectronics.

  • 23.
    Betker, Marie
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Harder, Constantin
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Erbes, Elisabeth
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Institute for X-ray Physics, Goettingen University, Friedrich Hund Platz 1, 37077 Goettingen, Germany, Friedrich Hund Platz 1.
    Heger, Julian Eliah
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Alexakis, Alexandros Efraim
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Sochor, Benedikt
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Chen, Qing
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Schwartzkopf, Matthias
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Körstgens, Volker
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Müller-Buschbaum, Peter
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1; Heinz Maier-Leibnitz Zentrum (MLZ), Technical University of Munich, Lichtenbergstr. 1, 85748 Garching, Germany, Lichtenbergstr. 1.
    Schneider, Konrad
    Abteilung Werkstofftechnik, Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany.
    Techert, Simone Agnes
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Institute for X-ray Physics, Goettingen University, Friedrich Hund Platz 1, 37077 Goettingen, Germany, Friedrich Hund Platz 1.
    Söderberg, Daniel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberprocesser.
    Roth, Stephan V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Sprayed Hybrid Cellulose Nanofibril-Silver Nanowire Transparent Electrodes for Organic Electronic Applications2023Inngår i: ACS Applied Nano Materials, E-ISSN 2574-0970, Vol. 6, nr 14, s. 13677-13688Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In times of climate change and resource scarcity, researchers are aiming to find sustainable alternatives to synthetic polymers for the fabrication of biodegradable, eco-friendly, and, at the same time, high-performance materials. Nanocomposites have the ability to combine several favorable properties of different materials in a single device. Here, we evaluate the suitability of two kinds of inks containing silver nanowires for the fast, facile, and industrial-relevant fabrication of two different types of cellulose-based silver nanowire electrodes via layer-by-layer spray deposition only. The Type I electrode has a layered structure, which is composed of a network of silver nanowires sprayed on top of a cellulose nanofibrils layer, while the Type II electrode consists of a homogeneous mixture of silver nanowires and cellulose nanofibrils. A correlation between the surface structure, conductivity, and transparency of both types of electrodes is established. We use the Haacke figure of merit for transparent electrode materials to demonstrate the favorable influence of cellulose nanofibrils in the spray ink by identifying Type II as the electrode with the lowest sheet resistance (minimum 5 ± 0.04 Ω/sq), while at the same time having a lower surface roughness and shorter fabrication time than Type I. Finally, we prove the mechanical stability of the Type II electrode by bending tests and its long-time stability under ambient conditions. The results demonstrate that the mixed spray ink of silver nanowires and cellulose nanofibrils is perfectly suitable for the fast fabrication of highly conductive organic nanoelectronics on an industrial scale.

  • 24.
    Biscari, Giuseppina
    et al.
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Fiorica, Calogero
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Fan, Yanmiao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Palumbo, Fabio Salvatore
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Indelicato, Serena
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Bongiorno, David
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Pitarresi, Giovanna
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Gellan gum-dopamine mediated in situ synthesis of silver nanoparticles and development of nano/micro-composite injectable hydrogel with antimicrobial activity2024Inngår i: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 258, artikkel-id 128766Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Infected skin wounds represent a serious health threat due to the long healing process and the risk of colonization by multi-drug-resistant bacteria. Silver nanoparticles (AgNPs) have shown broad-spectrum antimicrobial activity. This study introduces a novel approach to address the challenge of infected skin wounds by employing gellan gum-dopamine (GG-DA) as a dual-functional agent, serving both as a reducing and capping agent, for the in situ green synthesis of silver nanoparticles. Unlike previous methods, this work utilizes a spray-drying technique to convert the dispersion of GG-DA and AgNPs into microparticles, resulting in nano-into-micro systems (AgNPs@MPs). The microparticles, with an average size of approximately 3 μm, embed AgNPs with a 13 nm average diameter. Furthermore, the study explores the antibacterial efficacy of these AgNPs@MPs directly and in combination with other materials against gram-positive and gram-negative bacteria. The versatility of the antimicrobial material is showcased by incorporating the microparticles into injectable hydrogels. These hydrogels, based on oxidized Xanthan Gum (XGox) and a hyperbranched synthetic polymer (HB10K-G5-alanine), are designed with injectability and self-healing properties through Shiff base formation. The resulting nano-into-micro-into-macro hybrid hydrogel emerges as a promising biomedical solution, highlighting the multifaceted potential of this innovative approach in wound care and infection management.

  • 25.
    Biundo, Antonino
    et al.
    Univ Nat Resources & Life Sci, Vienna, Austria..
    Ribitsch, Doris
    Austrian Ctr Ind Biotechnol, Graz, Austria..
    Syrén, Per-Olof
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. Vienna, Austria..
    Guebitz, Georg M.
    Univ Nat Resources & Life Sci, Vienna, Austria..
    Increasing amide acceptance on a polyester-hydrolyzing enzyme2016Inngår i: New Biotechnology, ISSN 1871-6784, E-ISSN 1876-4347, Vol. 33, s. S105-S105Artikkel i tidsskrift (Annet vitenskapelig)
  • 26.
    Biundo, Antonino
    et al.
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy.;REWOW Srl, Via G Matarrese 10, I-70124 Bari, Italy..
    Stamm, Arne
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Gorgoglione, Ruggiero
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy..
    Syrén, Per-Olof
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Curia, Silvio
    Rowan Univ, Dept Chem Engn, 201 Mullica Hill Rd, Glassboro, NJ 08028 USA..
    Hauer, Bernhard
    Univ Stuttgart, Dept Tech Biochem, Allmandring 31, D-70569 Stuttgart, Germany..
    Capriati, Vito
    Univ Bari Aldo Moro, Dept Pharm Drug Sci, Via E Orabona 4, I-70125 Bari, Italy..
    Vitale, Paola
    Univ Bari Aldo Moro, Dept Pharm Drug Sci, Via E Orabona 4, I-70125 Bari, Italy..
    Perna, Filippo
    Univ Bari Aldo Moro, Dept Pharm Drug Sci, Via E Orabona 4, I-70125 Bari, Italy..
    Agrimi, Gennaro
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy..
    Pisano, Isabella
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy..
    Regio- and stereoselective biocatalytic hydration of fatty acids from waste cooking oils en route to hydroxy fatty acids and bio-based polyesters2023Inngår i: Enzyme and microbial technology, ISSN 0141-0229, E-ISSN 1879-0909, Vol. 163, artikkel-id 110164Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The development of biorefinery approaches is of great relevance for the sustainable production of valuable compounds. In accordance with circular economy principles, waste cooking oils (WCOs) are renewable resources and biorefinery feedstocks, which contribute to a reduced impact on the environment. Frequently, this waste is wrongly disposed of into municipal sewage systems, thereby creating problems for the environment and increasing treatment costs in wastewater treatment plants. In this study, regenerated WCOs, which were intended for the production of biofuels, were transformed through a chemo-enzymatic approach to produce hydroxy fatty acids, which were further used in polycondensation reaction for polyester production. Escherichia coli whole cell biocatalyst containing the recombinantly produced Elizabethkingia meningoseptica Oleate hydratase (Em_OhyA) was used for the biocatalytic hydration of crude WCOs-derived unsaturated free fatty acids for the production of hydroxy fatty acids. Further hydrogenation reaction and methylation of the crude mixture allowed the pro-duction of (R)-10-hydroxystearic acid methyl ester that was further purified with a high purity (> 90%), at gram scale. The purified (R)-10-hydroxystearic acid methyl ester was polymerized through a polycondensation reaction to produce the corresponding polyester. This work highlights the potential of waste products to obtain bio-based hydroxy fatty acids and polyesters through a biorefinery approach.

  • 27.
    Brett, Calvin J.
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Montani, Annaclaudia
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Medicinteknik och hälsosystem, Neuronik. Politecn Milan, Dept Chem Mat & Chem Engn Giulio Natta, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Schwartzkopf, M.
    DESY, Notkestr 85, D-22607 Hamburg, Germany..
    van Benthem, R. A. T. M.
    Eindhoven Univ Technol, Lab Phys Chem SPC, Groene Loper 5, NL-5600 MB Eindhoven, Netherlands.;DSM Mat Sci Ctr, Urmonderbaan 22, NL-6167 RD Geleen, Netherlands..
    Jansen, J. F. G. A.
    DSM Mat Sci Ctr, Urmonderbaan 22, NL-6167 RD Geleen, Netherlands..
    Griffini, G.
    Politecn Milan, Dept Chem Mat & Chem Engn Giulio Natta, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Roth, Stephan Volkher
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Johansson, Mats K.G.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Revealing structural evolution occurring from photo-initiated polymer network formation2020Inngår i: Communications Chemistry, E-ISSN 2399-3669, Vol. 3, nr 1, artikkel-id 88Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Photopolymerization is a key enabling technology offering spatial and temporal control to allow for future functional materials to be made to meet societal needs. However, gaining access to robust experimental techniques to describe the evolution of nanoscale morphology in photo-initiated polymeric systems has proven so far to be a challenging task. Here, we show that these physical transformations can be monitored and quantified at the nanoscale in situ and in real-time. It is demonstrated that the initial structural features of the liquid precursors significantly affect the final morphology and the physical properties of the resulting solid via the occurrence of local heterogeneities in the molecular mobility during the curing transformation. We have made visible how local physical arrestings in the liquid, associated with both cross-linking and vitrification, determine the length scale of the local heterogeneities forming upon curing, found to be in the 10-200nm range. Acomplete account of the structural evolution occurring during photopolymerisation is lacking. Here the physical changes occurring on the nanometer scale during photopolymerisation of acrylates are followed over time by FTIR, X-ray reflectometry, AFM, and GISAXS, offering insight into the mechanism by which initial composition influences the final morphology.

  • 28.
    Brett, Calvin
    et al.
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.
    Ohm, Wiebke
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Fricke, Bjorn
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Alexakis, Alexandros Efraim
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Laarmann, Tim
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Hamburg Ctr Ultrafast Imaging CUI, D-22761 Hamburg, Germany..
    Korstgens, Volker
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Materialien, D-85748 Garching, Germany..
    Muller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Materialien, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, D-85748 Garching, Germany..
    Söderberg, Daniel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberprocesser.
    Roth, Stephan, V
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Dept Fibre & Polymer Technol, Div Coating Technol, S-10044 Stockholm, Sweden..
    Nanocellulose-Assisted Thermally Induced Growth of Silver Nanoparticles for Optical Applications2021Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, nr 23, s. 27696-27704Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Optically responsive materials are present in everyday life, from screens to sensors. However, fabricating large-area, fossil-free materials for functional biocompatible applications is still a challenge today. Nanocelluloses from various sources, such as wood, can provide biocompatibility and are emerging candidates for templating organic optoelectronics. Silver (Ag) in its nanoscale form shows excellent optical properties. Herein, we combine both materials using thin-film large-area spray-coating to study the fabrication of optical response applications. We characterize the Ag nanoparticle formation by X-ray scattering and UV-vis spectroscopy in situ during growth on the nanocellulose template. The morphology and optical properties of the nanocellulose film are compared to the rigid reference surface SiO2. Our results clearly show the potential to tailor the energy band gap of the resulting hybrid material.

  • 29.
    Brännström, Sara
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Exploring bio-based monomers for UV-curable polymer networks2019Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Increased environmental awareness and concern has led to a high demand for sustainable, bio-based materials. Consequently, there is a need for research and development of new bio-based polymeric materials that can be synthesized via routes eliminating excessively toxic reactants and by-products. The work presented in this thesis has focused on the utilization of catalysis, mainly enzymatic, and photopolymerization in order to create efficient synthesis of polymeric networks from bio-based monomers.Polyesters from bio-based monomers have been polymerized in bulk and thereafter crosslinked by UV initiation to yield polymer networks with tunable properties. The synthesis was also studied more in detail by varying the different types of catalysts and comparing their effect on the polymer products. Polyesters are a promising class of polymers that can be made from bio-based resources due to the wide range of available bio-based carboxylic acids and alcohols that can be combined to yield many polymers with different properties. However, the synthesis of polyesters is rather time-consuming in order to reach high conversions.As a more efficient alternative, short chain esters monomers and oligomers that have vinyl ether (VE) functionalities were developed. These VE-esters can be synthesized partly from bio-based resources, such as acids, fatty acids and diols, and their synthesis is efficient with enzymatic catalysis. The VE functionality provides a reactive group which can be polymerized rapidly with cationic polymerization. In general, the vinyl ether-esters can be synthesized in less than one hour and crosslinked within a few minutes, which is significantly faster than traditional polyester-synthesis and crosslinking. The enzymatic synthesis of vinyl ether esters also provided a method for developing monomers with orthogonal functionality which was explored by developing functionalizable materials with a variety of macromolecular architectures.

    Fulltekst (pdf)
    fulltext
  • 30.
    Brännström, Sara
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Johansson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Enzymatically Synthesized Vinyl Ether-Disulfide Monomer Enablingan Orthogonal Combination of Free Radical and Cationic Chemistry toward Sustainable Functional Networks2019Inngår i: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, nr 3, s. 1308-1316, artikkel-id 10.1021/acs.biomac.8b01710Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    This work demonstrates a versatile and environmentally friendly route for the development of new orthogonal monomers that can be used for postfunctionalizable polymer networks. A monomer containing both vinyl ether (VE) and cyclic disulfide moieties was synthesized via enzyme catalysis under benign reaction conditions. The bifunctional monomer could be polymerized to form macromolecues with differing architectures by the use of either cationic or radical photo polymerization. When cationic polymerization was performed, a linear polymer was obtained with pendant disulfide units in the side chain, whereas in the presence of radical initiator, the VE reacted with the disulfide to yield a branched structure. The monomer was thereafter used to design networks that could be postfunctionalized; the monomer was cross-linked with cationic initiation together with a difunctional VE oligomer and after cross-linking the unreacted disulfides were coupled to RhodamineVE by radical UV-initiation.

  • 31.
    Bulut, Yusuf
    et al.
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Sochor, Benedikt
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Harder, Constantin
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Reck, Kristian
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Drewes, Jonas
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Xu, Zhuijun
    Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Jiang, Xiongzhuo
    Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany..
    Meinhardt, Alexander
    Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Univ Hamburg, Dept Phys, Notkestr 9-11, D-22607 Hamburg, Germany..
    Jeromin, Arno
    Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Kohantorabi, Mona
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Noei, Heshmat
    Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Keller, Thomas F.
    Ctr X Ray & Nano Sci CXNS, Deutsch Elektronen Synchtrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.;Univ Hamburg, Dept Phys, Notkestr 9-11, D-22607 Hamburg, Germany..
    Strunskus, Thomas
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Faupel, Franz
    Christian Albrechts Univ Kiel, Dept Mat Sci, Chair Multicomponent Mat, Fac Engn, Kaiserstr 2, D-24143 Kiel, Germany..
    Mueller-Buschbaum, Peter
    Tech Univ Munich, Sch Nat Sci, Dept Phys, Chair Funct Mat, James Franck Str 1, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, Lichtenbergerstr 1, D-85748 Garching, Germany..
    Roth, Stephan V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. Deutsch Elektronen Synchrotron DESY, Notkestr 85, D-22607 Hamburg, Germany.
    Diblock copolymer pattern protection by silver cluster reinforcement2023Inngår i: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 15, nr 38, s. 15768-15774Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Pattern fabrication by self-assembly of diblock copolymers is of significant interest due to the simplicity in fabricating complex structures. In particular, polystyrene-block-poly-4-vinylpyridine (PS-b-P4VP) is a fascinating base material as it forms an ordered micellar structure on silicon surfaces. In this work, silver (Ag) is applied using direct current magnetron sputter deposition and high-power impulse magnetron sputter deposition on an ordered micellar PS-b-P4VP layer. The fabricated hybrid materials are structurally analyzed by field emission scanning electron microscopy, atomic force microscopy, and grazing incidence small angle X-ray scattering. When applying simple aqueous posttreatment, the pattern is stable and reinforced by Ag clusters, making micellar PS-b-P4VP ordered layers ideal candidates for lithography. The pristine micellar pattern of the diblock copolymer PS-b-P4VP degrades upon drying of a water droplet, which can be stabilized and inhibited upon deposition of silver clusters.

  • 32.
    Cadet, Frederic
    et al.
    Univ Paris City, Inserm UMR S1134, Lab Excellence LABEX GR, DSIMB, Paris, France.;Univ Reunion, Paris, France.;PEACCEL, Artificial Intelligence Dept, Paris, France..
    Saavedra, Emma
    Inst Nacl Cardiol Ignacio Chavez, Dept Biochem, Mexico City, Mexico..
    Syrén, Per-Olof
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Gontero, Brigitte
    Aix Marseille Univ, CNRS, UMR7281 Bioenerget & Ingn Prot, Marseille, France..
    Editorial: Machine learning, epistasis, and protein engineering: From sequence-structure-function relationships to regulation of metabolic pathways2022Inngår i: Frontiers in Molecular Biosciences, E-ISSN 2296-889X, Vol. 9, artikkel-id 1098289Artikkel i tidsskrift (Annet vitenskapelig)
  • 33.
    Cattaruzza, Martina
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Fang, Yuan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Furo, Istvan
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Tillämpad fysikalisk kemi.
    Lindbergh, Göran
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemiteknik, Tillämpad elektrokemi.
    Liu, Fang
    Division of Materials and Manufacture, Department of Industrial and Materials Science, Chalmers University of Technology, SE-412 Gothenburg 96 Sweden.
    Johansson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Hybrid polymer-liquid lithium ion electrolytes: effect of porosity on the ionic and molecular mobility2023Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, E-ISSN 2050-7496, Vol. 11, nr 13, s. 7006-7015Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Alternative electrolyte systems such as hybrid electrolytes are much sought after to overcome safety issues related to liquid electrolytes in lithium ion batteries (LIBs). Hybrid solid-liquid electrolytes (HEs) like the heterogeneous structural battery electrolyte (SBE) consist of two discrete co-existing phases prepared by polymerization-induced phase separation: one solid polymer phase providing mechanical integrity and the other one a percolating liquid ion-conducting phase. The present work investigates the ion and the solvent mobility in a series of HEs using morphological, electrochemical impedance and NMR spectroscopic methods. All the dried HEs exhibit a porous structure with a broad pore size distribution stretching down to <10 nm diameter. Penetration of the individual components of the solution, that is the ions and the solvent, in the solid polymer phase is demonstrated. Yet, it is the pores that are the main ion conduction channels in the liquid-saturated HEs and, in general, translational mobility is strongly dependent on the volume fraction and size of the pores and, thereby, on the initial liquid electrolyte content. We also observe that the translational mobility of solvent and the ions vary differently with the pore volume fraction. This finding is explained by the presence of small mesopores where the mobility strongly depends on the specific interactions of the molecular constituent with the pore wall. These interactions are inferred to be stronger for the EC/PC solvent than for the ions. This study shows how the morphology and the chemical composition of HEs affect the ionic and molecular transport in the system.

  • 34.
    Chang, Tingru
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap. KTH, Centra, Center for the Advancement of Integrated Medical and Engineering Sciences, AIMES. Department of Neuroscience, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
    Leygraf, Christopher
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Herting, Gunilla
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Fan, Yanmiao
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Babu, Prasath
    KTH, Skolan för industriell teknik och management (ITM), Materialvetenskap.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Blomberg, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Kemi, Yt- och korrosionsvetenskap.
    Odnevall, Inger
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Centra, Center for the Advancement of Integrated Medical and Engineering Sciences, AIMES. Department of Neuroscience, Karolinska Institutet, SE-171 77 Stockholm, Sweden.
    Effect of blue light illumination on atmospheric corrosion and bacterial adhesion on copper2024Inngår i: Corrosion Science, ISSN 0010-938X, E-ISSN 1879-0496, Vol. 230, artikkel-id 111909Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The effect of blue light on atmospheric corrosion of Cu and on the antimicrobial properties was explored upon exposure mimicking the condition of hygienic surface disinfection. The results show that blue light illumination enhanced the formation of Cu2O, resulting in a slightly increased corrosion resistance of Cu without pre-deposited NaCl, whereas the enhanced formation of Cu2O, CuCl and/or Cu(OH)3Cl on copper with pre-deposited NaCl caused concomitant corrosion product flaking and a reduced corrosion resistance. The blue light induced enhancement of Cu corrosion led to increased surface roughness and more pronounced integration of bacteria within the corrosion products.

  • 35. Chen, Q.
    et al.
    Betker, Marie
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, Hamburg, 22607, Germany.
    Harder, C.
    Brett, Calvin J.
    KTH, Skolan för teknikvetenskap (SCI), Teknisk mekanik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, Hamburg, 22607, Germany.
    Schwartzkopf, M.
    Ulrich, N. M.
    Toimil-Molares, M. E.
    Trautmann, C.
    Söderberg, Daniel
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Weindl, C. L.
    Körstgens, V.
    Müller-Buschbaum, P.
    Ma, M.
    Roth, Stephan V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. Deutsches Elektronen-Synchrotron DESY, Notkestraße 85, Hamburg, 22607, Germany.
    Biopolymer-Templated Deposition of Ordered and Polymorph Titanium Dioxide Thin Films for Improved Surface-Enhanced Raman Scattering Sensitivity2022Inngår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 32, nr 6, artikkel-id 2108556Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Titanium dioxide (TiO2) is an excellent candidate material for semiconductor metal oxide-based substrates for surface-enhanced Raman scattering (SERS). Biotemplated fabrication of TiO2 thin films with a 3D network is a promising route for effectively transferring the morphology and ordering of the template into the TiO2 layer. The control over the crystallinity of TiO2 remains a challenge due to the low thermal stability of biopolymers. Here is reported a novel strategy of the cellulose nanofibril (CNF)-directed assembly of TiO2/CNF thin films with tailored morphology and crystallinity as SERS substrates. Polymorphous TiO2/CNF thin films with well-defined morphology are obtained by combining atomic layer deposition and thermal annealing. A high enhancement factor of 1.79 × 106 in terms of semiconductor metal oxide nanomaterial (SMON)-based SERS substrates is obtained from the annealed TiO2/CNF thin films with a TiO2 layer thickness of 10 nm fabricated on indium tin oxide (ITO), when probed by 4-mercaptobenzoic acid molecules. Common SERS probes down to 10 nm can be detected on these TiO2/CNF substrates, indicating superior sensitivity of TiO2/CNF thin films among SMON SERS substrates. This improvement in SERS sensitivity is realized through a cooperative modulation of the template morphology of the CNF network and the crystalline state of TiO2.

  • 36. Cho, I.
    et al.
    Prier, C. K.
    Jia, Z. -J
    Zhang, R. K.
    Görbe, Tamás
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Centra, Science for Life Laboratory, SciLifeLab.
    Arnold, F. H.
    Enantioselective Aminohydroxylation of Styrenyl Olefins Catalyzed by an Engineered Hemoprotein2019Inngår i: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 58, nr 10, s. 3138-3142Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Chiral 1,2-amino alcohols are widely represented in biologically active compounds from neurotransmitters to antivirals. While many synthetic methods have been developed for accessing amino alcohols, the direct aminohydroxylation of alkenes to unprotected, enantioenriched amino alcohols remains a challenge. Using directed evolution, we have engineered a hemoprotein biocatalyst based on a thermostable cytochrome c that directly transforms alkenes to amino alcohols with high enantioselectivity (up to 2500 TTN and 90 % ee) under anaerobic conditions with O-pivaloylhydroxylamine as an aminating reagent. The reaction is proposed to proceed via a reactive iron-nitrogen species generated in the enzyme active site, enabling tuning of the catalyst's activity and selectivity by protein engineering.

  • 37.
    Chumakova, Aleksandra
    et al.
    Outstation at Heinz Maier-Leibnitz Zentrum (MLZ), Institute of Crystallography (IfK), RWTH Aachen University, Lichtenbergstrasse 1, Garching, 85747, Germany; European Synchrotron Radiation Facility, 71 Avenue des Martyrs, Grenoble, 38000, France.
    Kirner, Felizitas
    Department of Earth and Environmental Sciences, Section of Crystallography, Ludwig-Maximilians-Universität München (LMU), Theresienstr. 41C, Munich, 80333, Germany.
    Chumakov, Andrei
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany.
    Roth, Stephan V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, Hamburg, 22607, Germany.
    Bosak, Alexeï
    European Synchrotron Radiation Facility, 71 Avenue des Martyrs, Grenoble, 38000, France.
    Sturm, Elena V.
    Department of Earth and Environmental Sciences, Section of Crystallography, Ludwig-Maximilians-Universität München (LMU), Theresienstr. 41C, Munich, 80333, Germany.
    Exploring the Crystalline Structure of Gold Mesocrystals Using X-ray Diffraction2023Inngår i: Crystals, ISSN 2073-4352, Vol. 13, nr 8, artikkel-id 1204Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mesocrystals are a class of nanostructured material where individual nanocrystals are arranged in a distinct crystallographic orientation. The multiple-length-scale order in such materials plays an essential role in the emergent physical and chemical phenomena. Our work studies the structure of a faceted mesocrystal composed of polystyrene-functionalized single crystalline gold nanoparticles using complementary ultrasmall- and wide-angle X-ray scattering (USAXS and WAXS) with electron microscopy. The results of the data analysis shed some light on the details of the microscopic structure of mesocrystals and their structuration principle.

  • 38.
    Cobo Sanchez, Carmen
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Inorganic and organic polymer-grafted nanoparticles: their nanocomposites and characterization2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Nanocomposites (NCs) have been widely studied in the past decades due to the promising properties that nanoparticles (NPs) offer to a polymer matrix, such as increased thermal stability and non-linear electrical resistivity. It has also been shown that the interphase between the two components is the key to achieving the desired improvements. In addition, polymer matrices are often hydrophobic while NPs are generally hydrophilic, leading to NP aggregation. To overcome these challenges, NPs can be surface-modified by adding specific molecules and polymers. In the present work, a range of organic and inorganic NPs have been surface-modified with polymers synthesized by atom transfer radical polymerization (ATRP) or surface-initiated ATRP (SI-ATRP).Cellulose nanofibrils (CNF) and cellulose nanocrystals (CNC) are highly crystalline NPs that can potentially increase the Young’s modulus of the NC. In this study, a matrix-free NC was prepared by physisorption of a block-copolymer containing a positively charged (quaternized poly(2-(dimethylamino)ethyl methacrylate), qPDMAEMA) and a thermo-responsive (poly di(ethylene glycol) methyl ether methacrylate, PDEGMA). The modified CNF exhibited a thermo-responsive, reversible behavior. CNCs were polymer-modified either via SI-ATRP or physisorbed with poly (butyl methacrylate) (PBMA) to improve the dispersion and interphase between them and a polycaprolactone (PCL) matrix during extrusion. The mechanical properties of the NCs containing CNC modified via SI-ATRP were superior to the reference and unmodified materials, even at a high relative humidity.Reduced graphene oxide (rGO) and aluminum oxide (Al2O3) are interesting for electrical and electronic applications. However, the matrices used for these applications, such as poly(ethylene-co-butyl acrylate) (EBA) and low density polyethylene (LDPE) are mainly hydrophobic, while the NPs are hydrophilic. rGO was modified via SI-ATRP using different chain lengths of PBMA and subsequently mixed with an EBA matrix. Al2O3 was modified with two lengths of poly(lauryl methacrylate) (PLMA), and added to LDPE prior to extrusion. Agglomeration and dispersion of the NCs were dependent on the lengths and miscibilities of the grafted polymers and the matrices. rGO-EBA NCs showed non-linear direct current (DC) resistivity upon modification, as the NP dispersion improved with increasing PBMA length. Al2O3-LDPE systems improved the mechanical properties of the NCs when low amounts of NPs (0.5 to 1 wt%) were added, while decreasing power dissipation on the material.Finally, PLMA-grafted NPs with high polymer quantities and two grafting densities in Al2O3 and silicon oxide (SiO2) nanoparticles were synthesized by de-attaching some of the silane groups from the surfaces, either by hydrolysis or by a mild tetrabutylammonium fluoride (TBAF) cleavage. These compounds were characterized and compared to the bulk PLMA, and were found to have very interesting thermal properties.

    Fulltekst (pdf)
    PhD Thesis Carmen Cobo
  • 39.
    Colding-Rasmussen, Thomas
    et al.
    Department of Orthopedic Surgery, Hvidovre University Hospital, Kettegaard Allé 30, Hvidovre, 2650, Denmark.
    Schwarzenberg, Peter
    AO Research Institute Davos, Clavadelerstrasse 8, Davos, 7270, Switzerland.
    Horstmann, Peter Frederik
    Department of Orthopedic Surgery, Gentofte Hospital, Gentofte Hospitalsvej 1, Hellerup, 2900, Denmark.
    Ottesen, Casper Bent Smedegaard
    Department of Orthopedic Surgery, Copenhagen University Hospital, Blegdamsvej 9, Copenhagen, Rigshospitalet, 2100, Denmark.
    San Jacinto García, Jorge
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Hutchinson, Daniel John
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Petersen, Michael Mørk
    epartment of Orthopedic Surgery, Copenhagen University Hospital, Blegdamsvej 9, Copenhagen, Rigshospitalet, 2100, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, Copenhagen, 2200, Denmark.
    Varga, Peter
    AO Research Institute Davos, Clavadelerstrasse 8, Davos, 7270, Switzerland.
    Tierp-Wong, Christian Nai En
    Department of Orthopedic Surgery, Hvidovre University Hospital, Kettegaard Allé 30, Hvidovre, 2650, Denmark; Faculty of Health and Medical Sciences, University of Copenhagen, Blegdamsvej 3B, Copenhagen, 2200, Denmark.
    Biomechanical Variability and Usability of a Novel Customizable Fracture Fixation Technique2023Inngår i: Bioengineering, E-ISSN 2306-5354, Vol. 10, nr 10, artikkel-id 1146Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A novel in situ customizable osteosynthesis technique, Bonevolent™ AdhFix, demonstrates promising biomechanical properties under the expertise of a single trained operator. This study assesses inter- and intra-surgeon biomechanical variability and usability of the AdhFix osteosynthesis platform. Six surgeons conducted ten osteosyntheses on a synthetic bone fracture model after reviewing an instruction manual and completing one supervised osteosynthesis. Samples underwent 4-point bending tests at a quasi-static loading rate, and the maximum bending moment (BM), bending stiffness (BS), and AdhFix cross-sectional area (CSA: mm²) were evaluated. All constructs exhibited a consistent appearance and were suitable for biomechanical testing. The mean BM was 2.64 ± 0.57 Nm, and the mean BS was 4.35 ± 0.44 Nm/mm. Statistically significant differences were observed among the six surgeons in BM (p < 0.001) and BS (p = 0.004). Throughout ten trials, only one surgeon demonstrated a significant improvement in BM (p < 0.025), and another showed a significant improvement in BS (p < 0.01). A larger CSA corresponded to a statistically significantly higher value for BM (p < 0.001) but not for BS (p = 0.594). In conclusion, this study found consistent biomechanical stability both across and within the surgeons included, suggesting that the AdhFix osteosynthesis platform can be learned and applied with minimal training and, therefore, might be a clinically viable fracture fixation technique. The variability in BM and BS observed is not expected to have a clinical impact, but future clinical studies are warranted.

  • 40.
    Duan, Shanghong
    et al.
    Chalmers Univ Technol, Dept Ind & Mat Sci, SE-41296 Gothenburg, Sweden..
    Cattaruzza, Martina
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Tu, Vinh
    Chalmers Univ Technol, Dept Ind & Mat Sci, SE-41296 Gothenburg, Sweden..
    Auenhammer, Robert M.
    Chalmers Univ Technol, Dept Ind & Mat Sci, SE-41296 Gothenburg, Sweden..
    Jaenicke, Ralf
    Tech Univ Carolo Wilhelmina Braunschweig, Inst Appl Mech, Pockelsstr 3, D-38106 Braunschweig, Germany..
    Johansson, Mats
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Liu, Fang
    Chalmers Univ Technol, Dept Ind & Mat Sci, SE-41296 Gothenburg, Sweden..
    Asp, Leif E.
    Chalmers Univ Technol, Dept Ind & Mat Sci, SE-41296 Gothenburg, Sweden..
    Three-dimensional reconstruction and computational analysis of a structural battery composite electrolyte2023Inngår i: COMMUNICATIONS MATERIALS, ISSN 2662-4443, Vol. 4, nr 1, artikkel-id 49Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Structural batteries are multifunctional composite materials that can carry mechanical load and store electrical energy. Their multifunctionality requires an ionically conductive and stiff electrolyte matrix material. For this purpose, a bi-continuous polymer electrolyte is used where a porous solid phase holds the structural integrity of the system, and a liquid phase, which occupies the pores, conducts lithium ions. To assess the porous structure, three-dimensional topology information is needed. Here we study the three-dimensional structure of the porous battery electrolyte material using combined focused ion beam and scanning electron microscopy and transfer into finite element models. Numerical analyses provide predictions of elastic modulus and ionic conductivity of the bi-continuous electrolyte material. Characterization of the three-dimensional structure also provides information on the diameter and volume distributions of the polymer and pores, as well as geodesic tortuosity. Structural battery composites contain a porous solid phase that holds the structural integrity of the system with a liquid phase in the pores. Here, the porous structure is studied using combined focused ion beam and scanning electron microscopy and transferred into finite element models.

  • 41.
    Engström, Joakim
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Tailored adhesion of PISA-latexes for cellulose modification and new materials2019Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis is focused on applying modification chemistry to already known cellulosic substrates from wood (i.e. cellulose nanofibrils, CNFs, and cellulose nanocrystals, CNCs). The modification is needed to overcome the drawbacks with the nanocellulosics alone, such as sensitivity to water (hydrophilicity) and the brittle material properties (however great stiffness). The first aim is to incorporate nanocellulosics into hydrophobic degradable materials of poly(ε-caprolactone) (PCL), resulting in aggregation if not modified. The challenge is to reach high fraction of nanocellulosics, whilst maintaining the flexibility of PCL and improving the properties of the resulting nanocomposite with the corresponding stiffness of the nanocellulosics. The second aim is to increase toughness and strain-at-break for nanocomposite materials of CNF-networks, to increase the plastic deformation equivalent of fossil-based polymeric materials such as polypropylene (PP). Aiming to achieve these goals, the thesis also includes new synthetic strategies of tailored-made set of block copolymers as modifying components. The modifying components, were synthesised by surfactant-free emulsion polymerisation and polymerisation induced self-assembly (PISA), so called PISA-latexes.

    Two types of cationic polyelectrolytes, (poly(2-dimethylaminoethy methacrylate) (PDMAEMA) and poly(N-[3-(dimethylamino)propyl] methacrylamide (PDMAPMA)), being the corona of the latex, were synthesised. Followed by chain-extension with different hydrophobic monomers such as methyl methacrylate and butyl methacrylate, making up the core polymer of the resulting PISA-latex. The cationic PISA-latexes show narrow size distributions and the glass transition (Tg) of the core polymer can be varied between -40 °C to 150 °C. The PISA-latexes show strong adhesion to silica and cellulose surfaces as assessed by quartz crystal microbalance (QCM-D). Results also indicate that latexes with Tg below room temperature, considered soft, behave different in the wet state than latexes with Tg above room temperature, considered rigid. The softer latexes form clusters (visualised by imaging with microscopy and atomic force measurements (AFM)) and undergo film formation in the wet state. The latter, shown by colloidal probe measurements using AFM resulting in very large work of adhesion and pull-off forces.

    The PISA-latexes compatibilize CNCs and different CNFs with PCL as a matrix polymer, observed by a small increase in stiffness for the final nanocomposites, however not at a level expected by rule-of-mixtures. The promising wet feeding technique results in large increase in stiffness but maintain PCL’s flexibility, above 200% strain-at-break, which is rarely observed for CNF-reinforced nanocomposites. The, in this case, rigid latex facilitate the dispersion of CNFs in the matrix without aggregation, until finally coalescing after processing and possibly giving rise to improved adhesion between CNF and the latex in the matrix, indicated by rheology measurements. Lastly, new nanocomposite films consisting of 75wt% CNF and 25wt% of PISA-latexes were produced and evaluated. The results show that CNF and rigid 100 nm sized PISA-latex, with PMMA core, gives a very tough double network, with strain-at-break above 28%, stiffness of 3.5 GPa and a strength of 110 MPa. These are impressive properties compared to commonly used fossil-based plastic materials.

    Fulltekst (pdf)
    Tailored adhesion of PISA-latexes for cellulose modification and new materials
  • 42.
    Engström, Joakim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Asem, Heba
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Brismar, Hjalmar
    KTH, Centra, Science for Life Laboratory, SciLifeLab. KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik.
    Zhang, Yuning
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    In situ encapsulation of Nile red or Doxorubicin during RAFT-mediated emulsion polymerization via polymerization-induced self-assembly for biomedical applications2020Inngår i: Macromolecular Chemistry and Physics, ISSN 1022-1352, E-ISSN 1521-3935Artikkel i tidsskrift (Fagfellevurdert)
    Fulltekst (pdf)
    fulltext
    Fulltekst (pdf)
    fulltext
  • 43.
    Engström, Joakim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Asem, Heba
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Brismar, Hjalmar
    KTH, Tidigare Institutioner (före 2005), Fysik. KTH, Centra, Science for Life Laboratory, SciLifeLab. KTH, Skolan för teknikvetenskap (SCI), Tillämpad fysik.
    Zhang, Yuning
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Malkoch, Michael
    KTH, Tidigare Institutioner (före 2005), Fiber- och polymerteknologi. KTH, Tidigare Institutioner (före 2005), Polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malmström, Eva
    KTH, Tidigare Institutioner (före 2005), Fiber- och polymerteknologi.
    In situ encapsulation of Nile red or Doxorubicinduring RAFT‐mediated emulsion polymerizationvia PISAManuskript (preprint) (Annet vitenskapelig)
  • 44.
    Engström, Joakim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Benselfelt, Tobias
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    D'Agosto, Franck
    Université de Lyon, Univ Lyon 1, CPE Lyon, CNRS UMR 5265, C2P2 (Chemistry, Catalysis, Polymers & Processes), LCPP, 69616 Villeurbanne, France .
    Lansalot, Muriel
    Université de Lyon, Univ Lyon 1, CPE Lyon, CNRS UMR 5265, C2P2 (Chemistry, Catalysis, Polymers & Processes), LCPP, 69616 Villeurbanne, France .
    Carlmark, Anna
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. RISE.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Tailoring adhesion of anionic surfaces using cationic PISA-latexes – towards tough nanocellulose materials in the wet state2019Inngår i: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 11, s. 4287-4302Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Cationic latexes with Tgs ranging between −40 °C and 120 °C were synthesised using n-butyl acrylate (BA) and/or methyl methacrylate (MMA) as the core polymers. Reversible addition–fragmentation chain transfer (RAFT) combined with polymerisation-induced self-assembly (PISA) allowed for in situ chain-extension of a cationic macromolecular RAFT agent (macroRAFT) of poly(N-[3-(dimethylamino)propyl] methacrylamide) (PDMAPMA), used as stabiliser in so-called surfactant-free emulsion polymerisation. The resulting narrowly distributed nanosized latexes adsorbed readily onto silica surfaces and to model surfaces of cellulose nanofibrils, as demonstrated by quartz crystal microbalance with dissipation monitoring (QCM-D) measurements. Adsorption to anionic surfaces increased when increasing ionic strength to 10 mM, indicating the influence of the polyelectrolyte effect exerted by the corona. The polyelectrolyte corona affected the interactions in the wet state, the stability of the latex and re-dispersibility after drying. The QCM-D measurements showed that a lower Tg of the core results in a more strongly interacting adsorbed layer at the solid–liquid interface, despite a comparable adsorbed mass, indicating structural differences of the investigated latexes in the wet state. The two latexes with Tg below room temperature (i.e. PBATg-40 and P(BA-co-MMA)Tg3) exhibited film formation in the wet state, as shown by AFM colloidal probe measurements. It was observed that P(BA-co-MMA)Tg3 latex resulted in the largest pull-off force, above 200 m Nm−1 after 120 s in contact. The strongest wet adhesion was achieved with PDMAPMA-stabilized latexes soft enough to allow for interparticle diffusion of polymer chains, and stiff enough to create a strong adhesive joint. Fundamental understanding of interfacial properties of latexes and cellulose enables controlled and predictive strategies to produce strong and tough materials with high nanocellulose content, both in the wet and dry state.

  • 45.
    Engström, Joakim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Brett, Calvin
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för teknikvetenskap (SCI), Mekanik.
    Körstgens, V.
    Müller-Buschbaum, P.
    Ohm, W.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Roth, Stephan V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Core–Shell Nanoparticle Interface and Wetting Properties2020Inngår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 30, nr 15, artikkel-id 1907720Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Latex colloids are among the most promising materials for broad thin film applications due to their facile surface functionalization. Yet, the effect of these colloids on chemical film and wetting properties cannot be easily evaluated. At the nanoscale, core–shell particles can deform and coalesce during thermal annealing, yielding fine-tuned physical properties. Two different core–shell systems (soft and rigid) with identical shells but with chemically different core polymers and core sizes are investigated. The core–shell nanoparticles (NPs) are probed during thermal annealing in order to investigate their behavior as a function of nanostructure size and rigidity. X-ray scattering allows to follow the re-arrangement of the NPs and the structural evolution in situ during annealing. Evaluation by real-space imaging techniques reveals a disappearance of the structural integrity and a loss of NP boundaries. The possibility to fine-tune the wettability by tuning the core–shell NPs morphology in thin films provides a facile template methodology for repellent surfaces.

  • 46.
    Engström, Joakim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Hatton, Fiona
    Loughborough Univ, Dept Mat, Loughborough, Leics, England..
    Benselfelt, Tobias
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Freire, Carmen
    Univ Aveiro, Aveiro Inst Mat, Aveiro, Portugal..
    Vilela, Carla
    Univ Aveiro, Aveiro Inst Mat, Aveiro, Portugal..
    Boujemaoui, Assya
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Sanchez, Carmen
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Lo Re, Giada
    Chalmers Univ Technol, Gothenburg, Sweden..
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    D'Agosto, Franck
    UCBL, CPE Lyon, C2P2, CNRS,CPE, Bat 308F, Villeurbanne, France..
    Lansalot, Muriel
    UCBL, CPE Lyon, C2P2, CNRS,CPE, Bat 308F, Villeurbanne, France..
    Carlmark, Anna
    RISE, Stockholm, Sweden..
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Tailored PISA-latexes for modification of nanocellulosics: Investigating compatibilizing and plasticizing effects2019Inngår i: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Artikkel i tidsskrift (Annet vitenskapelig)
  • 47.
    Engström, Joakim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Reid, Michael S.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Brotherton, E. E.
    Dainton Building, Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, UK .
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Armes, S. P.
    Dainton Building, Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, UK .
    Hatton, F. L.
    Dainton Building, Department of Chemistry, University of Sheffield, Brook Hill, Sheffield, South Yorkshire, UK .
    Investigating the adsorption of anisotropic diblock copolymer worms onto planar silica and nanocellulose surfaces using a quartz crystal microbalance2021Inngår i: Polymer Chemistry, ISSN 1759-9954, E-ISSN 1759-9962, Vol. 12, nr 42, s. 6088-6100Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Electrostatic adsorption of cationic polyelectrolytes onto anionic cellulosic substrates is an attractive route for facile surface modification of biorenewable materials. Recently, attention has focused on adsorbing cationic spherical diblock copolymer nanoparticles onto model cellulose and/or nanocellulosic substrates. Herein, we investigate physical adsorption of highly anisotropic copolymer worms bearing either anionic or cationic charge onto planar silica, cellulose nanocrystal (CNC) or cellulose nanofibril (CNF) surfaces using quartz crystal microbalance with dissipation monitoring. Electrostatic interactions dominate in the case of anionic silica and CNC surfaces because the adsorbed mass of cationic worms was greater than that of anionic worms. However, either anionic or cationic worms could be adsorbed onto in situ generated CNF substrates, suggesting that additional interactions were involved: hydrogen bonding, van der Waals forces, and possibly covalent bond formation. Scanning electron and atomic force microscopy studies of the dried planar substrates after adsorption experiments confirmed the presence of adsorbed copolymer worms. Finally, composite worm/CNF films exhibited restricted swelling behavior when immersed in water compared to reference CNF films, suggesting that the worms reinforce CNF films by acting as a physical crosslinker. This study is the first investigation of the physical adsorption of highly anisotropic diblock copolymer worms onto cellulosic surfaces.

  • 48.
    Engström, Joakim
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Stamm, Arne
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Tengdelius, Mattias
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Syrén, Per-Olof
    KTH, Centra, Science for Life Laboratory, SciLifeLab. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Fogelström, Linda
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Malmström, Eva
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi.
    Cationic latexes of bio‐based hydrophobicmonomer Sobrerol methacrylate (SobMA)Manuskript (preprint) (Annet vitenskapelig)
  • 49.
    Erlandsson, Johan
    et al.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Fiberteknologi.
    Pettersson, Torbjörn
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Ingverud, Tobias
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    Granberg, H.
    Larsson, Per A.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för teknikvetenskap (SCI), Centra, VinnExcellens Centrum BiMaC Innovation.
    Malkoch, Michael
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik.
    Wågberg, Lars
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi. KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Centra, Wallenberg Wood Science Center.
    On the mechanism behind freezing-induced chemical crosslinking in ice-templated cellulose nanofibril aerogels2018Inngår i: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, nr 40, s. 19371-19380Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The underlying mechanism related to freezing-induced crosslinking of aldehyde-containing cellulose nanofibrils (CNFs) has been investigated, and the critical parameters behind this process have been identified. The aldehydes introduced by periodate oxidation allows for formation of hemiacetal bonds between the CNFs provided the fibrils are in sufficiently close contact before the water is removed. This is achieved during the freezing process where the cellulose components are initially separated, and the growth of ice crystals forces the CNFs to come into contact in the thin lamellae between the ice crystals. The crosslinked 3-D structure of the CNFs can subsequently be dried under ambient conditions after solvent exchange and still maintain a remarkably low density of 35 kg m-3, i.e. a porosity greater than 98%. A lower critical amount of aldehydes, 0.6 mmol g-1, was found necessary in order to generate a crosslinked 3-D CNF structure of sufficient strength not to collapse during the ambient drying. The chemical stability of the 3-D structure can be further enhanced by converting the hemiacetals to acetals by treatment with an alcohol under acidic conditions.

  • 50.
    Euchler, E.
    et al.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Sambale, A. K.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Schneider, K.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Uhlig, K.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Boldt, R.
    Leibniz-Institut für Polymerforschung, Dresden, Germany.
    Stommel, M.
    Leibniz-Institut für Polymerforschung, Dresden, Germany; Technische Universität Dresden, Germany.
    Stribeck, A.
    Universität Hamburg, Germany.
    Schwartzkopf, M.
    Deutsches Elektronen-Synchrotron, Hamburg, Germany.
    Rothkirch, A.
    Deutsches Elektronen-Synchrotron, Hamburg, Germany.
    Roth, Stephan V.
    KTH, Skolan för kemi, bioteknologi och hälsa (CBH), Fiber- och polymerteknologi, Ytbehandlingsteknik. Deutsches Elektronen-Synchrotron, Hamburg, Germany.
    Beamline-implemented stretching devices for in situ X-ray scattering experiments2022Konferansepaper (Fagfellevurdert)
    Abstract [en]

    Two recently developed experimental devices for investigating soft matter deformation are presented. Both devices exploit the capabilities of a modern synchrotron beamline to enable advanced and highly precise materials-science experiments in which X-ray scattering is registered. The devices can be operated both in monotonic as well as cyclic mode and are implemented into a beamline at DESY, Hamburg (Germany). Hence, relevant experimental parameters, such as displacement, force and temperature, are recorded synchronously with the individual X-ray scattering patterns. In addition, spatial variation of materials deformation can be monitored and recorded with optical microscopy. This unique sample environment enables in situ X-ray experiments in transmission, i.e. small- or wide-angle X-ray scattering (SAXS or WAXS), and in grazing-incidence geometry, i.e. grazing-incidence (GI-) SAXS or WAXS. One device with stepper motors is designed for studies of slow, (quasi-) static deformation and the other one with pneumatic actuators can be used for fast, impact deformation. Both devices are available to external beamline users, too.

123456 1 - 50 of 251
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