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  • 1.
    Andrén, Oliver C. J.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Ingverud, Tobias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Hult, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Håkansson, Joakim
    Bogestål, Yalda
    Caous, Josefin S.
    Blom, Kristina
    Zhang, Yuning
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Andersson, Therese
    Pedersen, Emma
    Björn, Camilla
    Löwenhielm, Peter
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Antibiotic-Free Cationic Dendritic Hydrogels as Surgical-Site-Infection-Inhibiting Coatings2019In: Advanced Healthcare Materials, ISSN 2192-2640, E-ISSN 2192-2659, Vol. 8, no 5Article in journal (Refereed)
    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.

  • 2.
    Arseneault, Mathieu
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Granskog, Viktor
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Khosravi, Sara
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Heckler, Ilona
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Mesa-Antunez, Pablo
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Hult, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Zhang, Yuning
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Highly crosslinked triazine-trione materials for fracture fixation based on TEC and TYC chemistryManuscript (preprint) (Other academic)
  • 3.
    Asem, Heba
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Design of Functional Polymeric Nanoparticles for Biomedical Applications2020Doctoral thesis, comprehensive summary (Other academic)
    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.

  • 4.
    Asem, Heba
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Experimental Cancer Medicine (ECM), Department of Laboratory Medicine, NOVUM, Karolinska Institutet (KI), Stockholm, Sweden; Department of Materials Science, Institute of Graduate Studies and Research, University of Alexandria, Alexandria, Egypt.
    Abd El-Fattah, Ahmed
    Nafee, Noha
    Zhao, Ying
    Khalil, Labiba
    Muhammed, Mamoun
    KTH, School of Information and Communication Technology (ICT), Materials- and Nano Physics, Functional Materials, FNM.
    Hassan, Moustapha
    Kandil, Sherif
    Development and biodistribution of a theranostic aluminumphthalocyanine nanophotosensitizer2016In: Photodiagnosis and Photodynamic Therapy, ISSN 1572-1000, E-ISSN 1873-1597, Vol. 13, p. 48-57Article in journal (Refereed)
  • 5.
    Asem, Heba
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Zheng, Wenyi
    Division of Experimental Cancer Medicine (ECM), Department of Laboratory Medicine (LABMED), Karolinska Institutet, SE-141 86 Stockholm, Sweden.
    Nilsson, Fritjof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Zhang, Yuning
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Hedenqvist, Mikael S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Hassan, Moustapha
    Clinical Research Centrum, Department of Stem Cell Transplantation (CAST), Karolinska University Hospital-Huddinge, SE-141 86 Stockholm, Sweden.
    Malmström, Eva
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    Functional nano-carriers for drug delivery by surface engineering of polymeric nanoparticles post-PISAManuscript (preprint) (Other academic)
    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.

  • 6.
    Benselfelt, Tobias
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Nordenström, Malin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Lindstrom, Stefan B.
    Linkoping Univ, Div Solid Mech, Dept Management & Engn, S-58183 Linkoping, Sweden..
    Wågberg, Lars
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology. 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 Biointerfaces2019In: Advanced Materials Interfaces, ISSN 2196-7350, Vol. 6, no 13, article id 1900333Article in journal (Refereed)
    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.

  • 7. Boström, M.
    et al.
    Corkery, Robert
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Lima, E. R. A.
    Malyi, O. I.
    Buhmann, S. Y.
    Persson, C.
    Brevik, I.
    Parsons, D. F.
    Fiedler, J.
    Dispersion Forces Stabilize Ice Coatings at Certain Gas Hydrate Interfaces That Prevent Water Wetting2019In: ACS Earth and Space Chemistry, ISSN 2472-3452, Vol. 3, no 6, p. 1014-1022Article in journal (Refereed)
    Abstract [en]

    Gas hydrates formed in oceans and permafrost occur in vast quantities on Earth representing both a massive potential fuel source and a large threat in climate forecasts. They have been predicted to be important on other bodies in our solar systems such as Enceladus, a moon of Saturn. CO 2 -hydrates likely drive the massive gas-rich water plumes seen and sampled by the spacecraft Cassini, and the source of these hydrates is thought to be due to buoyant gas hydrate particles. Dispersion forces can in some cases cause gas hydrates at thermal equilibrium to be coated in a 3-4 nm thick film of ice, or to contact water directly, depending on which gas they contain. As an example, the results are valid at a quadruple point of the water-CO 2 gas hydrate system, where a film is formed not only for the model with pure ice but also in the presence of impurities in water or in the ice layer. These films are shown to significantly alter the properties of the gas hydrate clusters, for example, whether they float or sink. It is also expected to influence gas hydrate growth and gas leakage.

  • 8.
    Brännström, Sara
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Exploring bio-based monomers for UV-curable polymer networks2019Doctoral thesis, comprehensive summary (Other academic)
    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.

  • 9.
    Brännström, Sara
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Johansson, Mats
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Enzymatically Synthesized Vinyl Ether-Disulfide Monomer Enablingan Orthogonal Combination of Free Radical and Cationic Chemistry toward Sustainable Functional Networks2019In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 3, p. 1308-1316, article id 10.1021/acs.biomac.8b01710Article in journal (Refereed)
    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.

  • 10. Cho, I.
    et al.
    Prier, C. K.
    Jia, Z. -J
    Zhang, R. K.
    Görbe, Tamás
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Arnold, F. H.
    Enantioselective Aminohydroxylation of Styrenyl Olefins Catalyzed by an Engineered Hemoprotein2019In: Angewandte Chemie International Edition, ISSN 1433-7851, E-ISSN 1521-3773, Vol. 58, no 10, p. 3138-3142Article in journal (Refereed)
    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.

  • 11.
    Cobo Sanchez, Carmen
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Inorganic and organic polymer-grafted nanoparticles: their nanocomposites and characterization2018Doctoral thesis, comprehensive summary (Other academic)
    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.

    The full text will be freely available from 2020-04-24 14:42
  • 12.
    Engström, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Tailored adhesion of PISA-latexes for cellulose modification and new materials2019Doctoral thesis, comprehensive summary (Other academic)
    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.

  • 13.
    Engström, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Asem, Heba
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Brismar, Hjalmar
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences (SCI), Applied Physics.
    Zhang, Yuning
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    In situ encapsulation of Nile red or Doxorubicin during RAFT-mediated emulsion polymerization via polymerization-induced self-assembly for biomedical applications2020In: Macromolecular Chemistry and Physics, ISSN 1022-1352, E-ISSN 1521-3935Article in journal (Refereed)
  • 14.
    Engström, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Asem, Heba
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Brismar, Hjalmar
    KTH, Superseded Departments (pre-2005), Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences (SCI), Applied Physics.
    Zhang, Yuning
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Malkoch, Michael
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology. KTH, Superseded Departments (pre-2005), Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, Superseded Departments (pre-2005), Fibre and Polymer Technology.
    In situ encapsulation of Nile red or Doxorubicinduring RAFT‐mediated emulsion polymerizationvia PISAManuscript (preprint) (Other academic)
  • 15.
    Engström, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Benselfelt, Tobias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, 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, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. RISE.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Tailoring adhesion of anionic surfaces using cationic PISA-latexes – towards tough nanocellulose materials in the wet state2019In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 11, p. 4287-4302Article in journal (Refereed)
    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.

  • 16.
    Engström, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Hatton, Fiona
    Loughborough Univ, Dept Mat, Loughborough, Leics, England..
    Benselfelt, Tobias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Freire, Carmen
    Univ Aveiro, Aveiro Inst Mat, Aveiro, Portugal..
    Vilela, Carla
    Univ Aveiro, Aveiro Inst Mat, Aveiro, Portugal..
    Boujemaoui, Assya
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Sanchez, Carmen
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Lo Re, Giada
    Chalmers Univ Technol, Gothenburg, Sweden..
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, 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, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Tailored PISA-latexes for modification of nanocellulosics: Investigating compatibilizing and plasticizing effects2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 17.
    Engström, Joakim
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Stamm, Arne
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Tengdelius, Mattias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Syrén, Per-Olof
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Cationic latexes of bio‐based hydrophobicmonomer Sobrerol methacrylate (SobMA)Manuscript (preprint) (Other academic)
  • 18.
    Erlandsson, Johan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Pettersson, Torbjörn
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Ingverud, Tobias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Granberg, H.
    Larsson, Per A.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    On the mechanism behind freezing-induced chemical crosslinking in ice-templated cellulose nanofibril aerogels2018In: Journal of Materials Chemistry A, ISSN 2050-7488, Vol. 6, no 40, p. 19371-19380Article in journal (Refereed)
    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.

  • 19.
    Farhat, Wissam
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Stamm, Arne
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Robert-Monpate, Maxime
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. Ecole Super Chim Organ & Minerale, 1 Allee Reseau Jean Marie Buckmaster, F-60200 Compiegne, France.
    Biundo, Antonino
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Syrén, Per-Olof
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Biocatalysis for terpene-based polymers2019In: Zeitschrift für Naturforschung C - A Journal of Biosciences, ISSN 0939-5075, E-ISSN 1865-7125, Vol. 74, no 3-4, p. 90-99Article in journal (Refereed)
    Abstract [en]

    Accelerated generation of bio-based materials is vital to replace current synthetic polymers obtained from petroleum with more sustainable options. However, many building blocks available from renewable resources mainly contain unreactive carbon-carbon bonds, which obstructs their efficient polymerization. Herein, we highlight the potential of applying biocatalysis to afford tailored functionalization of the inert carbocyclic core of multicyclic terpenes toward advanced materials. As a showcase, we unlock the inherent monomer reactivity of norcamphor, a bicyclic ketone used as a monoterpene model system in this study, to afford polyesters with unprecedented backbones. The efficiencies of the chemical and enzymatic Baeyer-Villiger transformation in generating key lactone intermediates are compared. The concepts discussed herein are widely applicable for the valorization of terpenes and other cyclic building blocks using chemoenzymatic strategies.

  • 20. Fei, Ye
    et al.
    Barrefelt, Åsa
    Asem, Heba
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Abedi-Valugerdi, Manuchehr
    El-Serafi, Ibrahim
    Saghafian, Maryam
    Abu-Salah, Khalid
    Alrokayan, Salman
    Muhammed, Mamoun
    Hassan, Moustapha
    Biodegradable polymeric vesicles containing magnetic nanoparticles,quantum dots and anticancer drugs for drug delivery and imaging2014In: Biomaterials, ISSN 0142-9612, E-ISSN 1878-5905, Vol. 35, p. 3885-3894Article in journal (Refereed)
    Abstract [en]

    We have developed biodegradable polymeric vesicles as a nanocarrier system for multimodal bio-imaging and anticancer drug delivery. The poly(lactic-co-glycolic acid) (PLGA) vesicles were fabricated by encapsulating inorganic imaging agents of superparamagnetic iron oxide nanoparticles (SPION), manganese-doped zinc sulfide (Mn:ZnS) quantum dots (QDs) and the anticancer drug busulfan into PLGA nanoparticles via an emulsion-evaporation method. T2∗-weighted magnetic resonance imaging (MRI) of PLGA-SPION-Mn:ZnS phantoms exhibited enhanced negative contrast with r2∗ relaxivity of approximately 523 s(-1) mM(-1) Fe. Murine macrophage (J774A) cellular uptake of PLGA vesicles started fluorescence imaging at 2 h and reached maximum intensity at 24 h incubation. The drug delivery ability of PLGA vesicles was demonstrated in vitro by release of busulfan. PLGA vesicle degradation was studied in vitro, showing that approximately 32% was degraded into lactic and glycolic acid over a period of 5 weeks. The biodistribution of PLGA vesicles was investigated in vivo by MRI in a rat model. Change of contrast in the liver could be visualized by MRI after 7 min and maximal signal loss detected after 4 h post-injection of PLGA vesicles. Histological studies showed that the presence of PLGA vesicles in organs was shifted from the lungs to the liver and spleen over time.

  • 21.
    Fogelström, Linda
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Norström, Emelie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Khabbaz, Farideh
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Brucher, Jorg
    Holmen, Holmen Dev, Örnskoldsvik, Sweden..
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, Stockholm, Sweden.;KTH Royal Inst Technol, Dept Fibre & Polymer Technol, Stockholm, Sweden..
    A fully green wood adhesive based on hemicelluloses derived from pulp processes2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 22.
    Fogelström, Linda
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Stamm, Arne
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Tengdelius, Mattias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Syrén, Per-Olof
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH Royal Inst Technol, Fibre & Polymer Technol, Stockholm, Sweden..
    Malmström, Eva
    KTH Royal Inst Technol, Dept Fibre & Polymer Technol, Stockholm, Sweden..
    New chemo-enzymatic pathways for sustainable terpene-based polymeric materials2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 23.
    Francon, Hugo
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Benselfelt, Tobias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Granberg, Hjalmar
    RISE Bioecon, Stockholm, Sweden..
    Larsson, Per A.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Wågberg, Lars
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, Fibre & Polymer Technol, Stockholm, Sweden..
    3D printable nanocellulose aerogels via a green crosslinking approach and a facile evaporation procedure2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 24.
    Garcia Gallego, Sandra
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Andrén, Oliver C. J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Accelerated Chemoselective Reactions to Sequence-Controlled Heterolayered Dendrimers2020In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126Article in journal (Refereed)
    Abstract [en]

    Chemoselective reactions are a highly desirable approach to generate well-defined functional macromolecules. Their extraordinary efficiency and selectivity enable the development of flawless structures, such as dendrimers, with unprecedented structure-to-property capacity but with typically tedious synthetic protocols. Here we demonstrate the potency of chemoselective reactions to accomplish sequence-controlled heterolayered dendrimers. An accurate accelerated design of bis-MPA monomers with orthogonally complementary moieties and a wisely selected chemical toolbox generated highly complex monodisperse dendrimers through simplified protocols. The versatility of the strategy was proved by obtaining different dendritic families with different properties after altering the order of addition of the monomers. Moreover, we evaluated the feasibility of the one-pot approach toward these heterolayered dendrimers as proof-of-concept.

  • 25.
    Granskog, Viktor
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Thiol-Ene/Yne Adhesives for Tissue Fixation2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The utilization of adhesives in surgery has not reached its full potential and research in the field is encouraged by the surgeons’ desire for improved alternatives to today’s tissue fixation strategies. Here, adhesive resins based on thiol-ene coupling (TEC) chemistry or thiol-yne coupling (TYC) chemistry are exploited to develop tissue adhesives that cure fast and on-demand via photoinitiation. In order to make safer adhesives, macromolecular components and systems with high conversion of functional groups were developed to minimize leakage of unreacted monomers.To develop macromolecular resin components, allyl-functional dendritic-linear-dendritic (DLD) co-polymers were synthesized with a poly(ethylene glycol) (PEG) core chain and hyperbranched structures of 2,2-bis(hydroxymethyl) propionic acid (bis-MPA) to capitalize on the rheological properties of dendritic structures. The dendritic structures interfered with the crystallization of the PEG segment and the DLD’s liquid appearance enabled their use as macromolecular components without solvent. The DLDs were cured with a thiol crosslinker and the strategy disclosed degradable soft tissue adhesives with good adhesion to wet porcine skin.Mussel inspired dopamine derivatives was evaluated as adhesion-enhancing primers for bone adhesives. The addition of NaOH to the primer solutions increased the shear bond strengths of the adhesive to bone. The highest bond strengths with the tested dopamine derivatives were obtained when a combination of thiol and ene-functional derivatives were used.With inspiration from dental resin adhesives, a fully TEC based adhesive system was developed with excellent shear bond strength to wet bone substrates. The adhesive system enabled superior fixation of phalangeal fracture models compared to the daily used Kirschner wires and could even compete with a screw fixated metal plate. The adhesive materials proved biocompatible in initial in vitro and in vivo studies.Strong and rigid materials for fracture fixation were developed via a strategy of using highly crosslinked triazine-trione monomers and TEC or TYC chemistry. The development resulted in TYC resin based materials with mechanical properties that very well can compete with poly(ether ether ketone) (PEEK) that is used in biomedical load bearing applications due to its high strength, toughness and inertness.

  • 26.
    Granskog, Viktor
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    García-Gallego, Sandra
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    von Kieseritzky, Johanna
    Department of Clinical Science and Education and the Department of Hand Surgery, Karolinska Institutet.
    Rosendahl, Jennifer
    RISE Research Institutes of Sweden, Bioscience and Materials–Medical Device Technology.
    Stenlund, Patrik
    RISE Research Institutes of Sweden, Bioscience and Materials–Medical Device Technology.
    Zhang, Yuning
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Petronis, Sarunas
    RISE Research Institutes of Sweden, Bioscience and Materials–Medical Device Technology.
    Lyvén, Benny
    RISE Research Institutes of Sweden, Bioscience and Materials–Medical Device Technology.
    Arner, Marianne
    Department of Clinical Science and Education and the Department of Hand Surgery, Karolinska Institutet.
    Håkansson, Joakim
    RISE Research Institutes of Sweden, Bioscience and Materials–Medical Device Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    High-Performance Thiol–Ene Composites Unveil a New Era of Adhesives Suited for Bone Repair2018In: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, no 26, article id 1800372Article in journal (Refereed)
    Abstract [en]

    The use of adhesives for fracture fixation can revolutionize the surgical procedures toward more personalized bone repairs. However, there are still no commercially available adhesive solutions mainly due to the lack of biocompatibility, poor adhesive strength, or inadequate fixation protocols. Here, a surgically realizable adhesive system capitalizing on visible light thiol–ene coupling chemistry is presented. The adhesives are carefully designed and formulated from a novel class of chemical constituents influenced by dental resin composites and self-etch primers. Validation of the adhesive strengthis conducted on wet bone substrates and accomplished via fiber-reinforced adhesive patch (FRAP) methodology. The results unravel, for the first time, on the promise of a thiol–ene adhesive with an unprecedented shear bondstrength of 9.0 MPa and that surpasses, by 55%, the commercially available acrylate dental adhesive system Clearfil SE Bond of 5.8 MPa. Preclinical validation of FRAPs on rat femur fracture models details good adhesion to the bone throughout the healing process, and are found biocompatible not giving rise to any inflammatory response. Remarkably, the FRAPs are found to withstand loads up to 70 N for 1000 cycles on porcine metacarpal fractures outperforming clinically used K-wires and match metal plates and screw implants.

  • 27.
    He, Yunjuan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Boluk, Yaman
    Univ Alberta, Dept Civil & Environm Engn, Edmonton, AB, Canada..
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Ahniyaz, Anwar
    RISE Res Inst Sweden, Div Biosci & Mat, Stockholm, Sweden..
    Deltin, Tomas
    PTE Coatings AB, Gamleby, Sweden..
    Claesson, Per M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Comparative study of CNC and CNF as additives in waterborne acrylate-based anti-corrosion coatings2019In: Journal of Dispersion Science and Technology, ISSN 0193-2691, E-ISSN 1532-2351Article in journal (Refereed)
    Abstract [en]

    Nanocomposite coatings are of great interest as barrier coatings since synergy effects between matrix and additive properties can be achieved. This, however, requires favorable additive-matrix interactions to provide a strong interphase (interface region). In this work we elucidate the properties of two environmentally benign nanocomposite coatings based on a waterborne acrylate formulation with additives from renewable sources, i.e. either cellulose nanocrystals, CNC; or, alternatively, cellulose nanofibrils, CNF. We focus on the corrosion protective properties of these coatings and discuss the reason why the nanocomposite with CNC displays favorable corrosion protection properties whereas that with CNF does not. To this end we utilized scanning electron microscopy, water contact angle measurement, Fourier transform infrared spectroscopy and electrochemical impedance spectroscopy techniques to investigate the microstructure, surface wetting, interactions between cellulosic materials and matrix as well as corrosion protective properties of both composite coatings.

  • 28.
    Hendrikse, Natalie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. Swedish Orphan Biovitrum AB, Stockholm, Sweden.
    Charpentier, Gwenaelle
    KTH, Centres, Science for Life Laboratory, SciLifeLab. ESCOM, 1 Allee Reseau Jean Marie Buckmaster, F-60200 Compiegne, France..
    Nordling, Erik
    Swedish Orphan Biovitrum AB, Stockholm, Sweden..
    Syrén, Per-Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Protein Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. Swedish Orphan Biovitrum AB, Stockholm, Sweden.
    Ancestral diterpene cyclases show increased thermostability and substrate acceptance2018In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 285, no 24, p. 4660-4673Article in journal (Refereed)
    Abstract [en]

    Bacterial diterpene cyclases are receiving increasing attention in biocatalysis and synthetic biology for the sustainable generation of complex multicyclic building blocks. Herein, we explore the potential of ancestral sequence reconstruction (ASR) to generate remodeled cyclases with enhanced stability, activity, and promiscuity. Putative ancestors of spiroviolene synthase, a bacterial class I diterpene cyclase, display an increased yield of soluble protein of up to fourfold upon expression in the model organism Escherichia coli. Two of the resurrected enzymes, with an estimated age of approximately 1.7 million years, display an upward shift in thermostability of 7-13 degrees C. Ancestral spiroviolene synthases catalyze cyclization of the natural C-20-substrate geranylgeranyl diphosphate (GGPP) and also accept C-15 farnesyl diphosphate (FPP), which is not converted by the extant enzyme. In contrast, the consensus sequence generated from the corresponding multiple sequence alignment was found to be inactive toward both substrates. Mutation of a nonconserved position within the aspartate-rich motif of the reconstructed ancestral cyclases was associated with modest effects on activity and relative substrate specificity (i.e., k(cat)/K-M for GGPP over k(cat)/K-M for FPP). Kinetic analyses performed at different temperatures reveal a loss of substrate saturation, when going from the ancestor with highest thermostability to the modern enzyme. The kinetics data also illustrate how an increase in temperature optimum of biocatalysis is reflected in altered entropy and enthalpy of activation. Our findings further highlight the potential and limitations of applying ASR to biosynthetic machineries in secondary metabolism.

  • 29.
    Hendrikse, Natalie M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. Swedish Orphan Biovitrum AB, Stockholm, SE-112 76, Sweden.
    Holmberg Larsson, Albin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. Swedish Orphan Biovitrum AB, Stockholm, SE-112 76, Sweden.
    Svensson Gelius, S.
    Kuprin, S.
    Nordling, E.
    Syrén, Per-Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Protein Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Exploring the therapeutic potential of modern and ancestral phenylalanine/tyrosine ammonia-lyases as supplementary treatment of hereditary tyrosinemia2020In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 10, no 1, article id 1315Article in journal (Refereed)
    Abstract [en]

    Phenylalanine/tyrosine ammonia-lyases (PAL/TALs) have been approved by the FDA for treatment of phenylketonuria and may harbour potential for complementary treatment of hereditary tyrosinemia Type I. Herein, we explore ancestral sequence reconstruction as an enzyme engineering tool to enhance the therapeutic potential of PAL/TALs. We reconstructed putative ancestors from fungi and compared their catalytic activity and stability to two modern fungal PAL/TALs. Surprisingly, most putative ancestors could be expressed as functional tetramers in Escherichia coli and thus retained their ability to oligomerize. All ancestral enzymes displayed increased thermostability compared to both modern enzymes, however, the increase in thermostability was accompanied by a loss in catalytic turnover. One reconstructed ancestral enzyme in particular could be interesting for further drug development, as its ratio of specific activities is more favourable towards tyrosine and it is more thermostable than both modern enzymes. Moreover, long-term stability assessment showed that this variant retained substantially more activity after prolonged incubation at 25 °C and 37 °C, as well as an increased resistance to incubation at 60 °C. Both of these factors are indicative of an extended shelf-life of biopharmaceuticals. We believe that ancestral sequence reconstruction has potential for enhancing the properties of enzyme therapeutics, especially with respect to stability. This work further illustrates that resurrection of putative ancestral oligomeric proteins is feasible and provides insight into the extent of conservation of a functional oligomerization surface area from ancestor to modern enzyme.

  • 30.
    Hohn, Nuri
    et al.
    Tech Univ Munich, Lehrstuhl Funkt Mat, Dept Phys, James Franck Str 1, D-85748 Garching, Germany. chwartzkopf, Matthias; Roth, Stephan V..
    Shlosser, Steffen J.
    Biessmann, Lorenz
    Song, Lin
    Grott, Sebastian
    Xia, Senlin
    Wang, Kun
    Schwartzkopf, Matthias
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Mueller-Buschbaum, Peter
    Impact of Catalytic Additive on Spray Deposited and Nanoporous Titania in Films Observed via in Situ X-ray Scattering: Implications for hanced Photovoltaics2018In: ACS Applied Nano Materials, ISSN 2574-0970, Vol. 1, no 8, p. 4227-4235Article in journal (Refereed)
    Abstract [en]

    With the aim of obtaining nanostructured titania thin films for the tential use in hybrid or dye sensitized solar cells, the amphiphilic block copolymer polystyrene-b-poly(ethylene oxide) is employed as a ructure directing template in combination with solgel chemistry. For sy upscaling, spraying is used as a deposition technique. In situ azing incidence small-angle X-ray scattering (GISAXS) measurements are rformed during spraying and show that most titania structures are ready formed within the solution prior to deposition. However, ructural rearrangement is enabled during the deposition period when all amounts of hydrochloric acid (HCl) are used as a catalytic ditive to the spray solution. This behavior is ascribed to an altering the reaction dynamics and phase separation in the presence of HCl, ich significantly improves the templating effect of the employed block copolymer. With HCl as an additive the final nanoscale rphologies exhibit smaller pore sizes and strongly enhanced order as mpared to thin films sprayed from solutions that do not contain HCl as antified with atomic force microscopy, scanning electron microscopy, d GISAXS.

  • 31.
    Hult, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Versatile Synthetic Strategies to Highly Functional Polyesters and Polycarbonates2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Polymers have become ubiquitous in today’s society and are found in everything from household items to airplanes and automobiles. Synthetic polymeric materials are as diverse as their applications and their final properties are highly reliant on the building blocks and methods used to assemble them. In the field of biomedical materials, polyesters and polycarbonates have been hailed as excellent materials in large part due to their inherent hydrolytic degradability. With this in mind, careful choice of monomers can ensure that materials not only conform to the desired physical properties, but also elicit a favorable biological response. The utilization of post-polymerization modification of these promising materials has the capability of opening up further avenues to target even more advanced applications. Unfortunately, rigorous and difficult reaction conditions, including multi-step synthesis have to a certain extent held back the adoption of these complex functional materials in applied research. In a pragmatic approach, a sustainable framework was developed in this thesis to seek out more practical methods, limiting the amount of reaction steps and overtly hazardous chemicals.

    In a first study, we set out to simplify and scale-up the synthesis of cyclic carbonates with pendant functional groups, capable of undergoing controlled ring-opening polymerization. By avoiding the use of protective-group chemistry we were able two devise a two-step method to create a library of functional monomers. Results in this study show that reactive intermediates could be isolated on 100 g scales, which in a second step was functionalized with a desired alcohol.

    With this framework in mind, key practical decisions were made to drastically re-think the work up procedures for greater scalability of bis-MPA dendrimers. In this work, a more efficient, scalable and sustainable approach was devised. Elimination of traditional arduous purification steps led to the synthesis of monodisperse dendrimers up to the sixth generation, with 192 functional groups on 50 g scales. Further work included the omission of protective group-chemistry, using orthogonal functional groups to cut the number of synthetic steps by half.

    The know-how developed in the first two projects led us to pursue greater scalability of functional polycarbonates through a simpler polymerization technique. The method allowed the step-growth polymerization of functional materials from more easily accessible monomers isolated on 100 g scales. Subsequent polymerization afforded materials with glass transition temperatures in the range of -45 °C to 169 °C. The method served as a complement to cyclic carbonates, offering a wider range of functional monomers. Furthermore, by careful choice of assembly method, both alternating and scrambled compositions could be achieved.

    In a final study, we set out to take advantage of the scrambling mechanism. Control of the final composition of highly rigid degradable polycarbonates was pursued, using renewable building-blocks derived from sugar. In a proof of concept study, thermal and hydrolytic stability of these materials is shown to be dependent on both amount and configuration of each monomer in the final material.

  • 32.
    Hult, Daniel
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Garcia-Gallego, Sandra
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Ingverud, Tobias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Andrén, Oliver
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Degradable High Tg Sugar Derived Polycarbonates from Isosorbide and Dihydroxyacetone2018In: Polymer Chemistry, ISSN 1759-9954, E-ISSN 1759-9962, Vol. 9, no 17, p. 2238-2246Article in journal (Refereed)
    Abstract [en]

    Polycarbonates from isosorbide and dihydroxyacetone (DHA) have been synthesised using organocatalytic step-growth polymerization of their corresponding diols and bis-carbonylimidazolides monomers. By choice of feed ratio and monomer activation, either isosorbide or ketal protected DHA, random and alternating poly(Iso-co-DHA) carbonates have been formed. Thermal properties by DSC and TGA were herein strongly correlated to monomer composition. Dilution studies using 1H-NMR of a model compound DHA-diethyl carbonate in acetonitrile and deuterated water highlighted the influence of α-substituents on the keto/hydrate equilibrium of DHA. Further kinetics studies of in the pH* range of 4.7 to 9.6 serve to show the hydrolytic pH-profile of DHA-carbonates. The Hydrolytic degradation of deprotected polymer pellets show an increased degradation with increasing DHA content. Pellets with a random or alternating configuration show different characteristics in terms of mass loss and molecular weight loss profile over time.

  • 33.
    Ihrner, Niklas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Structural Lithium Ion Battery Electrolytes2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A major challenge in the electrification of vehicles in the transport industry is that batteries are heavy, which reduces their effectiveness in mobile applications. A solution to this is structural batteries, which are batteries that can carry mechanical load while simultaneously storing energy. This can potentially lead to large weight savings on a systems level, since they may allow replacement of load bearing structures with structural batteries. Carbon fibers are suitable for structural batteries because they have superb mechanical properties and readily intercalate lithium ions, i.e. they can be used as electrodes in a lithium ion battery. However, to utilize carbon fibers in structural batteries, a polymer (matrix) is needed to form a composite battery. The polymer is required to have high modulus and high ion transport properties, which are inversely related, to function as an electrolyte. This thesis focuses on the development and characterization of such polymer electrolytes.

    The first study was performed on a homogenous polymer electrolyte based on plasticized polyethylene glycol-methacrylate. The influence of crosslink density, salt concentration and plasticizer concentration on the mechanical and electrochemical properties were investigated. Increases in both ionic conductivity and storage modulus were obtained when, compared to non-plasticized systems. However, at high storage modulus (E’>500 MPa) the ionic conductivity (𝜎<10-7 S cm-1) is far from good enough for the realization of structural batteries.

    In a second study, phase separated systems were therefore investigated. Polymerization induced phase separation (PIPS) via UV-curing was utilized to the produce structural battery electrolytes (SBE), consisting of liquid electrolyte and a stiff vinyl ester thermoset. The effect of monomer structure and volume fraction of liquid electrolyte on the morphology, electrochemical and mechanical properties were investigated. High storage modulus (750 MPa) in combination with high ionic conductivity (1.5 x 10-4 S cm-1) were obtained at ambient temperature. A SBE carbon fiber lamina half-cell was prepared via vacuum infusion and electrochemically cycled vs lithium metal. The results showed that both ion transport and load transfer was enabled through the SBE matrix.

    In the third study the mechanical and electrochemical properties of the SBE-carbon fiber lamina were investigated and the multifunctional performance was evaluated. A new formulation of SBE, with a small addition of thiol monomer, were prepared with improved electrochemical and mechanical properties. The mechanical properties of the SBE carbon fiber lamina did not deteriorate after electrochemical cycling. The capacity of the SBE carbon fiber lamina half-cell was 232 ± 26 mAh g-1, at a C/20 charge rate. Furthermore, the lamina displayed multifunctional performance, compared to the monofunctional properties of its constituents.

    In the final study, a new curing method was investigated, since UV-curing cannot be used to prepare full-cell carbon fiber composite structural batteries. Thermal curing was investigated to prepare the SBE. The PIPS was not adversely affected by the change in curing method, and the length scale of the phase separation in the SBE was slightly larger compared to UV-cured SBEs. The thermally cured SBEs exhibited improved thermomechanical properties without a reduction in the electrochemical properties. Thermal curing did not affect the electrochemical properties of the SBE carbon fiber lamina, however the type of carbon fiber utilized was found to negatively affect the cycling performance.

  • 34.
    Ingverud, Tobias
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Exploring crosslinked networks of polymers and hybrid cellulose materials2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The field of polymer chemistry has in recent decades had an immense development, resulting in new functional materials with groundbreaking applications. This has been driven partly by strong interdisciplinary alliances between the fields of medicine, biology, chemistry, and materials science. Thermoresponsive block copolymers, have been built for their ability to self-assemble, giving possibility of encapsulation and release of medicine. The dendritic polymer family have been demonstrated as a prime example of highly reactive and interactive functional materials, suitable for biomedical applications. The importance of amines is greatly appreciated in general and especially in polymer chemistry, due to their nucleophilic characteristics in reactions, but also for their ability to interact with other species. There’s also an increase in awareness of standard of living, the effects of climate change and population growth. These are challenges, in need of our outmost focus and knowledge, to direct our path to, towards a more bio based circular economy. This starts, in Sweden, by taking better care of our forest and utilizing its resourceful crop. This thesis seek out spontaneous crosslinking, of various functional polymers, with focus towards hybridizing with nanocellulosic material.

    Initially, interactive permanently charged amine-functional thermoresponsive tri- and star-block copolymers were composed. These were evaluated and used as electrostatic macro-crosslinker of cellulose nanofibrils (CNFs), resulting in thermoresponsive, low dry weight content hydrogels, with notable temperature dependent storage modulus.

    Secondly, reactive and interactive amine-functional dendritic-linear-dendritic (DLD) species were constructed and evaluated in vitro and in vivo. The DLD scaffolds were utilized as fast-degrading, inhibiting surgical site infection (SSIs) antibacterial hydrogel coatings. The crosslinking of the poly(ethylene glycol) (PEG) system was optimized in order to create a two component system, which could be applied with dual syringes. This enabled instantaneous gelation under physiological conditions. The hydrogels moduli could be varied to match various tissues.

    Thirdly, insights and characterizations were provided in the commercial heterofunctional poly(amido amine) carboxylate hyperbranched Helux. Amine post-modifications and intrinsic heterofunctionality alterations of Helux were explored, by increasing the molecular weight and forming Helux self-crosslinked films. Furthermore, two component hydrogels based on Helux and PEG demonstrated curing temperature dependent moduli in the rheometer.

    Finally, utilizing Helux in combination with CNFs to demonstrate the potential to mix on the nanoscale without aggregation. The CNF-Helux could form hydrogels, and wet-stable thermo-crosslinked CNF-Helux composites assemblies such as films and aerogels, with further excess of amines ready for post-modifications of the crosslinked 3D-network.

    The full text will be freely available from 2020-04-16 12:13
  • 35.
    Ingverud, Tobias
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Erlandsson, Johan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    The combination of a dendritic polyampholyte and cellulose nanofibrils – a new type of functional materialManuscript (preprint) (Other academic)
  • 36.
    Ingverud, Tobias
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Helux: A heterofunctional hyperbranched poly(amido amine) carboxylateManuscript (preprint) (Other academic)
  • 37.
    Ingverud, Tobias
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Helux: A Heterofunctional Hyperbranched Poly(amido amine) Carboxylate2019In: ACS APPLIED POLYMER MATERIALS, ISSN 2637-6105, Vol. 1, no 7, p. 1845-1853Article in journal (Refereed)
    Abstract [en]

    Herein we present the first scientific report on the commercially available Helux 33/16 - a heterofunctional poly(amido amine carboxylate) hyperbranched polymer (Native Helux). The Native Helux, built from diethyl maleate (DEM) and diaminohexane (HMDA), was characterized, in part aided by reverse engineering of a similar scaffold with the same monomers. Different purification methods resulted in higher molecular weight polymers ranging from 8.4 to 51.7 kDa (M-w), and the Helux considered the purest, having 10 mmol (primary and secondary amines)/g as well as 2-4 mmol carboxylic/g Helux. Additionally, aqueous-mediated postmodifications of Helux were achieved including Michael addition, guanylation, and ring-opening of sultone, as well as water/ethyl acetate-mediated amidation of imidazole-activated pentenoic acid. The inherent heterofunctionality of Helux, amines and carboxylic groups, was further explored by a one-component self-cross-linking approach that yielded a dendritic poly(amido amine) network with autofluorescence-exhibiting properties and a T-g of 59 degrees C. The Helux network exhibited a storage modulus (G') of 7.9 MPa at 25 degrees C and in dry state, and 0.9 MPa (G') when plasticized by 50 wt % swelling (in water) of the network. Finally, dendritic hydrogels based on Helux were produced by a spontaneous NHS-amidation reaction with difunctional 10kPEG-NHS. The mechanical properties of the hydrogels were found to be dependent on the curing temperature for the hydrogel, yielding a G' of 8 and 14.5 kPa, a stress at break of 11.5 and 22.7 kPa, and a strain-at-break of 161 and 163%, at 25 and 37 degrees C, respectively.

  • 38.
    Jawerth, Marcus
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH Royal Institute of Technology.
    Thermoset resins using technical lignin as a base constituent2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The need to find sustainable paths for our society is imminent to tackle environmental concerns of today. The majority of all plastic materials are produced from crude oil but in the future a much larger portion must originate from renewable resources to address some of these problems. Aromatic molecules are often used when producing rigid and thermally stable polymeric materials but there are few natural sources for them. One is, however, the wood component lignin that is produced on a large scale from chemical pulping processes of biomass. Lignins aromatic structures could be an alternative for non-renewable aromatics in e.g. thermoset applications.

    The heterogeneity of lignin does however present some problems in terms of e.g. dispersity, solubility, diverse functionality, and varying polymer backbone structure. To tackle these challenges, work-up of lignin and thorough characterization are important to be able to produce materials with predetermined, predictable, properties. Technical lignins have functional groups that can be utilized as chemical handles for further modifications required for different material systems e.g. phenols, aliphatic hydroxyls, and carboxylic acids.

    This thesis focuses on how to utilize solvent fractionated, relatively well-characterized, LignoBoost Kraft lignin to produce thermoset resins by chemical modification and a crosslinking procedure. An efficient procedure to selectively allylate the phenolics, the most abundant functionality, of the lignin fractions has been developed and evaluated as well as a curing procedure using a thiol crosslinker and a thiol-ene reaction. The produced materials were analysed with regards to material properties, density, and morphology. The resins based on the selectively allylated lignin fractions were furthermore evaluated as a potential matrix for carbon fibre composites. It was shown that the material samples could be processed by pre-impregnating carbon fibres and form composite materials. The molecules of the lignin fraction were also used as core substrates in a ring-opening polymerization to produce functional star co-polymers. The procedure was evaluated and it could be shown that the lignin backbone was subjected to substantial structural changes of lignin inter-unit linkages.

    Lignin being one of the few large resources of naturally occurring aromatics has a big potential to be used for material applications where rigidity and thermal stability is important. This thesis attempts to add a few pieces towards such a goal.

    The full text will be freely available from 2020-06-01 09:38
  • 39.
    Jawerth, Marcus
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Brett, Calvin
    KTH, School of Engineering Sciences (SCI), Mechanics.
    Terrier, Cedric
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Larsson, Per Tomas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH Royal Inst Technol, Wallenberg Wood Sci Ctr, S-10044 Stockholm, Sweden..
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Lundmark, Stefan
    Perstorp AB, Innovat, S-28480 Perstorp, Sweden..
    Johansson, Mats
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH Royal Inst Technol, Div Coating Technol, Dept Fibre & Polymer Technol, S-10044 Stockholm, Sweden..
    Mechanical and Morphological Properties of Lignin-Based Thermosets2020In: ACS APPLIED POLYMER MATERIALS, ISSN 2637-6105, Vol. 2, no 2, p. 668-676Article in journal (Refereed)
    Abstract [en]

    The need for renewable alternatives for fossil-based aromatic material constituents is evident for a more sustainable society. Lignin is the largest source of naturally occurring aromatic compounds but has mainly been considered as waste material or energy source in the pulp and paper industry. Developments in extracting lignin from these processes provide a large source for renewable aromatic structures to be used in various applications. Producing thermosets out of lignin is a very promising route to utilize this raw material toward, for example, composite application. The buildup of the molecular network based on oligomeric lignin segments will be different from traditional thermoset analogues, where the constituents often are smaller molecules, and will have an effect on the material properties. In this work LignoBoost Kraft lignin is refined, chemically modified, and used to produce freestanding thermosets with different architectures and properties. These different thermosets are evaluated, and the possibilities to tailor the material properties through work-up and modification are demonstrated. Morphological studies on the formed thermosets using X-ray scattering show systematic differences in molecular stacking and aggregate sizes.

  • 40.
    Jawerth, Marcus
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Johansson, Mats
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Renewable thermosetting resins based on refined technical lignin: fractionation, modification and valorization2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 41.
    Johansson, Mats
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    New vinyl ether monomers via lipase catalysis towards cationically crosslinkable thermosets2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 42.
    Kaldéus, Tahani
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Surface modification approaches of cellulose nanofibrils and their effect on dispersibility2019Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In the strive to find and develop sustainable bio-based materials an increased interest for nanocellulosic materials as attractive alternatives has arisen during the past decades. This can be attributed to their abundant renewability, remarkable inherent mechanical properties and their capability to be chemically modified. Cellulose nanofibrils (CNFs) are commonly obtained from wood pulp fibres and prepared through mechanical, chemical and/or enzymatic treatments. However, due to their hydrophilic nature and tendency to self-aggregate, their surface chemistry need to be altered to fully utilise their inherent properties and enable their usage in conventional large-scale industrial processes.

    This thesis work focuses on elucidating the fundamental aspects of the colloidal stability of highly concentrated CNF dispersions and the redispersibility of dried CNFs. Small amounts of amine-terminated poly(ethylene glycol) (PEG) were used to sterically stabilise the CNFs at higher fibril concentrations and delay the dispersion-arrested state transition (Paper I). The redispersibility of dried CNFs was studied for differently charged CNFs as a function of redispersing agents such as carboxymethyl cellulose (CMC), PEG and lignin (Paper II).

    This thesis presents green, facile modification approaches as well as strategies for improved dispersibility and compatibility with polymer matrices. The commercially established carboxymethylation process was expanded with a subsequent functionality step, yielding a mild, versatile one-pot protocol for the preparation of bi-functional CNFs (Paper III). Further, reactive amphiphilic macromolecules with targeted side-chain functionalities were used to compatibilise the CNF surface by water-based approaches. In the first study, a macroinitiator was used for the development of a versatile, yet facile, protocol for the controlled polymerisation of both hydrophilic and hydrophobic monomers in water from the CNF surface (Paper IV). In the second study, a reactive macro-compatibiliser was used to molecularly engineer the interface between CNFs and a polymer matrix by reactive-melt processing, yielding nanocomposites with improved stiffness while maintaining the deformability (Paper V).

    The full text will be freely available from 2020-12-31 11:00
  • 43.
    Kaldéus, Tahani
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Nordenström, Malin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Erlandsson, Johan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Redispersibility properties of dried cellulose nanofibrils - influence on structure and mechanical propertiesManuscript (preprint) (Other academic)
  • 44.
    Kaldéus, Tahani
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Nordenström, Malin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Erlandsson, Johan
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Redispersibility properties of dried cellulose nanofibrils - influence on structure and mechanical properties2019In: Article in journal (Other academic)
  • 45.
    Kaldéus, Tahani
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Telaretti Leggieri, Maria Rosella
    Cobo Sanchez, Carmen
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    All-aqueous SI-ARGET ATRP from cellulose nanofibrils using hydrophilic and hydrophobic monomers2019In: Article in journal (Other academic)
  • 46.
    Kaldéus, Tahani
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Träger, Andrea
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Berglund, Lars
    KTH, School of Engineering Sciences (SCI), Aeronautical and Vehicle Engineering.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lo Re, Giada
    Chalmers University of Technology.
    Molecular engineering of cellulose-PCL bio-nanocomposite interface by reactive amphiphilic copolymer nanoparticles2019In: Article in journal (Refereed)
  • 47.
    Kürten, Charlotte
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Eriksson, Adam
    Maddalo, Gianluca
    Edfors, Fredrik
    Uhlén, Mathias
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Syrén, Per-Olof
    KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Engineering of water networks in class II terpene cyclases underscores the importance of amino acid hydration and entropy in biocatalysis and enzyme designManuscript (preprint) (Other academic)
  • 48.
    Lo Re, Giada
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Engström, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Wu, Qiong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Gedde, Ulf W.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Olsson, Richard
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Berglund, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Improved Cellulose Nanofibril Dispersion in Melt-Processed Polycaprolactone Nanocomposites by a Latex-Mediated Interphase and Wet Feeding as LDPE Alternative2018In: ACS Applied Nano Materials, ISSN 2574-0970, Vol. 1, no 6, p. 2669-2677Article in journal (Refereed)
    Abstract [en]

    This work reports the development of a sustainable and green one-step wet-feeding method to prepare tougher and stronger nanocomposites from biodegradable cellulose nanofibrils (CNF)/polycaprolactone (PCL) constituents, compatibilized with reversible addition fragmentation chain transfer-mediated surfactant-free poly(methyl methacrylate) (PMMA) latex nanoparticles. When a PMMA latex is used, a favorable electrostatic interaction between CNF and the latex is obtained, which facilitates mixing of the constituents and hinders CNF agglomeration. The improved dispersion is manifested in significant improvement of mechanical properties compared with the reference material. The tensile tests show much higher modulus (620 MPa) and strength (23 MPa) at 10 wt % CNF content (compared to the neat PCL reference modulus of 240 and 16 MPa strength), while maintaining high level of work to fracture the matrix (7 times higher than the reference nanocomposite without the latex compatibilizer). Rheological analysis showed a strongly increased viscosity as the PMMA latex was added, that is, from a well-dispersed and strongly interacting CNF network in the PCL.

  • 49.
    Långberg, Marie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. SWERIM, SE-16407 Kista, Sweden..
    Örnek, Cem
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Zhang, Fan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Cheng, J.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Liu, M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Granaes, E.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Wiemann, C.
    Res Ctr Julich, Peter Grunberg Inst PGI 6, D-52425 Julich, Germany..
    Gloskovskii, A.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Matveyev, Y.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Kulkarni, S.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Noei, H.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Keller, T. F.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Univ Hamburg, Phys Dept, D-20355 Hamburg, Germany..
    Lindell, D.
    SWERIM, SE-16407 Kista, Sweden..
    Kivisakk, U.
    AB Sandvik Mat Technol, SE-81181 Sandviken, Sweden..
    Lundgren, E.
    Lund Univ, Div Synchrotron Radiat Res, SE-22100 Lund, Sweden..
    Stierle, A.
    Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Univ Hamburg, Phys Dept, D-20355 Hamburg, Germany..
    Pan, Jinshan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Characterization of Native Oxide and Passive Film on Austenite/Ferrite Phases of Duplex Stainless Steel Using Synchrotron HAXPEEM2019In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 166, no 11, p. C3336-C3340Article in journal (Refereed)
    Abstract [en]

    A new measurement protocol was used for microscopic chemical analysis of surface oxide films with lateral resolution of 1 mu m. The native air-formed oxide and an anodic passive film on austenite and ferrite phases of a 25Cr-7Ni super duplex stainless steel were investigated using synchrotron hard X-ray photoemission electron microscopy (HAXPEEM). Pre-deposited Pt-markers, in combination with electron backscattering diffraction mapping (EBSD), allowed analysis of the native oxide on individual grains of the two phases and the passive film formed on the same area after electrochemical polarization of the sample. The results showed a certain difference in the composition of the surface films between the two phases. For the grains with (001) crystallographic face // sample surface, the native oxide film on the ferrite contained more Cr oxide than the austenite. Anodic polarization up to 1000 mV/(Ag/AgCl) in 1M NaCl solution at room temperature resulted in a growth of the Cr- and Fe-oxides, diminish of Cr-hydroxide, and an increased proportion of Fe3+ species. by ECS. This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 License (CC BY, http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse of the work in any medium, provided the original work is properly cited.

  • 50. Löhrer, F. C.
    et al.
    Körstgens, V.
    Semino, G.
    Schwartzkopf, M.
    Hinz, A.
    Polonskyi, O.
    Strunskus, T.
    Faupel, F.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Müller-Buschbaum, P.
    Following in Situ the Deposition of Gold Electrodes on Low Band Gap Polymer Films2020In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 12, no 1, p. 1132-1141Article in journal (Refereed)
    Abstract [en]

    Metal top electrodes such as gold are widely used in organic solar cells. The active layer can be optimized by modifications of the polymer band gap via side-chain engineering, and low band gap polymers based on benzodithiophene units such as PTB7 and PTB7-Th are successfully used. The growth of gold contacts on PTB7 and PTB7-Th films is investigated with in situ grazing incidence small-angle X-ray scattering (GISAXS) and grazing incidence wide-angle X-ray scattering (GIWAXS) during the sputter deposition of gold. From GIWAXS, the crystal structure of the gold film is determined. Independent of the type of side chain, gold crystals form in the very early stages and improve in quality during the sputter deposition until the late stages. From GISAXS, the nanoscale structure is determined. Differences in terms of gold cluster size and growth phase limits for the two polymers are caused by the side-chain modification and result in a different surface coverage in the early phases. The changes in the diffusion and coalescence behavior of the forming gold nanoparticles cause differences in the morphology of the gold contact in the fully percolated regime, which is attributed to the different amount of thiophene rings of the side chains acting as nucleation sites.

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