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  • 101. Berglin, M.
    et al.
    Elwing, H.
    Malkoch, Michael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Löwenhielm, P.
    Kelly, J.
    Lundgren, A.
    Hybrid nanoparticle arrays for measuring the interaction between cell adhesion ligands and macromolecules using SPR2011In: European Cells and Materials, ISSN 1473-2262, E-ISSN 1473-2262, Vol. 21, no SUPPL.1, p. 44-Article in journal (Refereed)
  • 102.
    Berglund, Lars
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Burgert, Ingo
    Swiss Fed Inst Technol, Inst Bldg Mat, Stefano Franscini Pl 3, CH-8093 Zurich, Switzerland.;EMPA Swiss Fed Labs Mat Testing & Res, Appl Wood Res Lab, CH-8600 Dubendorf, Switzerland..
    Bioinspired Wood Nanotechnology for Functional Materials2018In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 30, no 19, article id 1704285Article in journal (Refereed)
    Abstract [en]

    It is a challenging task to realize the vision of hierarchically structured nanomaterials for large-scale applications. Herein, the biomaterial wood as a large-scale biotemplate for functionalization at multiple scales is discussed, to provide an increased property range to this renewable and CO2-storing bioresource, which is available at low cost and in large quantities. The Progress Report reviews the emerging field of functional wood materials in view of the specific features of the structural template and novel nanotechnological approaches for the development of wood-polymer composites and wood-mineral hybrids for advanced property profiles and new functions.

  • 103. Bergnor, Elisabeth
    et al.
    Ek, Monica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Johansson, E
    The role of metal ions in TCF-bleaching.1994In: Proceedings 3rd European Workshop on Lignocellulosics and Pulp, 1994, p. 284-289Conference paper (Refereed)
  • 104.
    Bergström, Elina Mabasa
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Salmen, Lennart
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Joby Kochumalayil, Jose
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Biocomposites. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Berglund, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Plasticized xyloglucan for improved toughness-Thermal and mechanical behaviour2012In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 87, no 4, p. 2532-2537Article in journal (Refereed)
    Abstract [en]

    Tamarind seed xyloglucan is an interesting polysaccharide of high molar mass with excellent thermomechanical properties. Several plasticizers were studied in order to facilitate thermal processing and improve toughness (work to fracture) of xyloglucan film materials: sorbitol, urea, glycerol and polyethylene oxide. Films of different compositions were cast and studied by thermogravimetric analysis (TGA), calorimetry (DSC), dynamic mechanical thermal analysis (DMA) and tensile tests. Results are analysed and discussed based on mechanisms and practical considerations. Highly favourable characteristics were found with XG/sorbitol combinations, and the thermomechanical properties motivate further work on this material system, for instance as a matrix in biocomposite materials.

  • 105.
    Bhattacharya, Proma
    et al.
    KTH, School of Chemical Science and Engineering (CHE).
    Jansson, Miriam
    KTH, School of Chemical Science and Engineering (CHE).
    Wretstam, Sofia
    KTH, School of Chemical Science and Engineering (CHE).
    Kompositmaterial med cellulosabaserad grafenoxid2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med projektet var att förbättra polypropens gasbarriär genom att addera olika nanofyllmedel, grafenoxid och kalciumkarbonat. I detta projekt undersöktes främst hur genomsläppligheten av syrgasmolekyler, syrgaspermeabiliteten, ändrades när man tillsätter fyllmedel till polypropen med hjälp av MOCON. Resultaten visade att genomsläppligheten av syrgas minskade något med grafenoxid men blev sämre med den mindre tillsatsen av  kalciumkarbonat. Tester som utfördes gjordes med TGA och DSC men permabilitetstestet framhävs som det mest centrala. Resultaten som erhölls vid permabilitetsundersökningen tros komma av hål i filmerna på molekylär nivå, i dessa hål kan då molekylerna passera igenom filmen fritt.

     Övriga resultat pekar på att fyllmedlen inte påverkar polypropens smält- eller kristallisationstemperatur nämnvärt men att dess styrka reduceras.  Då polypropen är en mycket stark polymer så försämrar tillsatsen av fyllmedel styrkan hos materialet, däremot ökade E-modulen. Utöver det verkar inte fyllmedelet ha påverkat de fysikaliska egenskaperna så som Tg och Tc. Samtidigt som den termiska stabiliteten ökade med en tillsatts av GO förändrades den inte nämnvärt när kalciumkarbonat adderades utan den bröts ned vid ungefär samma temperatur som rent polypropen.

  • 106.
    Bi, Ran
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Lignocellulose Degradation by Soil Micro-organisms2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Lignocellulosic biomass is a sustainable resource with abundant reserves. Compared to petroleum ‐ based products, the biomass ‐ derived polymers and chemicals give better environmental profiles. A lot of research interest is focused on understanding the lignocellulose structures.

    Lignin, among the three major wood components, represents most difficulty for microbial degradation because of its complex structure and because cross ‐ linking to hemicellulose makes wood such a compact structure. Nevertheless, wood is naturally degraded by wood ‐ degrading micro ‐ organisms and modified and partly degraded residual of lignin goes into soil. Therefore soil serves as a good environment in which to search for special lignin ‐ degraders. In this thesis, different types of lignin have been used as sole carbon sources to screen for lignin ‐ degrading soil micro ‐ organisms. Eleven aerobic and three anaerobic microbe strains have been isolated and identified as able to grow on lignin. The lignin degradation patterns of selected strains have been studied and these partly include an endwise cleavage of  β‐ O ‐ 4 bonds in lignin and is more complex than simple hydrolytic degradation.

    As lignin exists in wood covalently bonded to hemicellulose, one isolated microbe strain, Phoma herbarum, has also been studied with regards to its ability to degrade covalent lignin polysaccharide networks (LCC). The results show that its culture filtrate can attack lignin ‐ polysaccharide networks in a manner different from that of the commercial enzyme product, Gammanase, possibly by selective cleavage of phenyl glucoside bonds. The effects on LCC of Phoma herbarum also enhance polymer extractability. Hot ‐ water extraction of a culture filtrate of Phoma herbarum ‐ treated fiberized spruce wood material gave an amount of extracted galactoglucomannan more than that given by the Gammanase ‐ treated material and non ‐ enzyme ‐ treated material.

    Over millions of years of natural evolution, micro ‐ organisms on the one hand develop so that they can degrade all wood components to get energy for growth, while plants on the other hand also continuously develop to defend from microbial attack. Compared with lignin and cellulose, hemicelluloses as major components of plant cell walls, are much more easily degraded, but hemicelluloses differ from cellulose in that they are acetylated to different extents. The biological functions of acetylation are not completely understood, but it is suggested is that one function is to decrease the microbial degradability of cell walls. By cultivation of soil micro ‐ organisms using mannans acetylated to deffernent degrees as sole carbon source on agar plates, we were able to see significant trends where the resistance towards microbial degradation of glucomannan and galactomannan increased with increasing degree of acetylation. Possible mechanisms and the technological significance of this are discussed. Tailoring the degree of acetylation of polysaccharide materials might slow down the biodegradation, making it possible to design a material with a degradation rate suited to its application.

  • 107.
    Bi, Ran
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Isolation and identification of soil microorganisms under anaerobic condition which is able to live on lignin as carbon source2012In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 243Article in journal (Other academic)
  • 108. Bianchi, F.
    et al.
    Agazzi, S.
    Riboni, N.
    Benyahia Erdal, Nejla
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Hakkarainen, Minna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Ilag, L. L.
    Anzillotti, L.
    Andreoli, R.
    Marezza, F.
    Moroni, F.
    Cecchi, R.
    Careri, M.
    Novel sample-substrates for the determination of new psychoactive substances in oral fluid by desorption electrospray ionization-high resolution mass spectrometry2019In: Talanta: The International Journal of Pure and Applied Analytical Chemistry, ISSN 0039-9140, E-ISSN 1873-3573, Vol. 202, p. 136-144Article in journal (Refereed)
    Abstract [en]

    A reliable screening and non invasive method based on the use of microextraction by packed sorbent coupled with desorption electrospray ionization-high resolution mass spectrometry was developed and validated for the detection of new psychoactive substances in oral fluid. The role of different sample substrates in enhancing signal intensity and stability was evaluated by testing the performances of two polylactide-based materials, i.e. non-functionalized and functionalized with carbon nanoparticles, and a silica-based material compared to commercially available polytetrafluorethylene supports. The best results were achieved by using the non-functionalized polylactide substrates to efficiently ionize compounds in positive ionization mode, whereas the silica coating proved to be the best choice for operating in negative ionization mode. LLOQs in the low μg/L, a good precision with CV% always lower than 16% and RR% in the 83(±4)-120(±2)% range, proved the suitability of the developed method for the determination of the analytes in oral fluid. Finally, the method was applied for screening oral fluid samples for the presence of psychoactive substances during private parties, revealing mephedrone in only one sample out of 40 submitted to analysis.

  • 109.
    Bladholm, Viktor
    et al.
    KTH, School of Chemical Science and Engineering (CHE).
    Britts, Adam
    KTH, School of Chemical Science and Engineering (CHE).
    Edberg, Alexandra
    KTH, School of Chemical Science and Engineering (CHE).
    Khawaja, Anmol
    KTH, School of Chemical Science and Engineering (CHE).
    Framställning av nanocellulosa och påverkan av råmaterialet2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den här rapporten behandlar framställning av nanocellulosa, CNF, och hur det kemiska innehållet för barr- respektive lövmassa påverkar framställningen. De massor som använts i undersökningen var båda ursprungligen från oblekta sulfatmassor. De blev först kloritdelignifierde och genomgick sedan alkalisk extraktion för att ta bort hemicellulosan. Innan massorna homogeniserades enzymbehandlades de med endoglukanas. De erhållna nanofibrerna karakteriserades genom kolhydratsanalys, mätning av polymerisationsgraden, konduktometrisk titrering, mätning av transmittans, AFM, röntgendiffraktion, centrifugering och DLS.

    Utifrån resultaten kunde det ses att mellan barr- och lövmassorna var barrmassan det bästa alternativet vid framställning av nanocellulosa. Inom barrmassorna var den kloritdelignifierade barrmassan det bästa alternativet vid framställning av nanocellulosa.

  • 110.
    Blomfeldt, Thomas O. J.
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Kuktaite, Ramune
    Plivelic, Tomás S.
    Rasheed, Faiza
    Johansson, Eva
    Hedenqvist, Mikael S.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Freeze-dried forms made from wheat glutenin- and gliadin-rich fractionsManuscript (preprint) (Other academic)
  • 111.
    Blomfeldt, Thomas O. J.
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Nilsson, Fritjof
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Holgate, Tim
    Xu, Jianxiao
    Johansson, Eva
    Hedenqvist, Mikael S.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymeric Materials.
    Thermal Conductivity and Combustion Properties of Wheat Gluten Foams2012In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 4, no 3, p. 1629-1635Article in journal (Refereed)
    Abstract [en]

    Freeze-dried wheat gluten foams were evaluated with respect to their thermal and fire-retardant properties, which are important for insulation applications. The thermal properties were assessed by differential scanning calorimetry, the laser flash method and a hot plate method. The unplasticised foam showed a similar specific heat capacity, a lower thermal diffusivity and a slightly higher thermal conductivity than conventional rigid polystyrene and polyurethane insulation foams. Interestingly, the thermal conductivity was similar to that of closed cell polyethylene and glass-wool insulation materials. Cone calorimetry showed that, compared to a polyurethane foam, both unplasticised and glycerol-plasticised foams had a significantly longer time to ignition, a lower effective heat of combustion and a higher char content. Overall, the unplasticised foam showed better fire-proof properties than the plasticized foam. The UL 94 test revealed that the unplasticised foam did not drip (form droplets of low viscous material) and, although the burning times varied, self-extinguished after flame removal. To conclude both the insulation and fire-retardant properties were very promising for the wheat gluten foam.

  • 112.
    Blomfeldt, Thomas O. J.
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Olsson, Richard T.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Menon, Mohan
    Plackett, David
    Johansson, Eva
    Hedenqvist, Mikael S.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Novel Foams Based on Freeze-Dried Renewable Vital Wheat Gluten2010In: Macromolecular materials and engineering (Print), ISSN 1438-7492, E-ISSN 1439-2054, Vol. 295, no 9, p. 796-801Article in journal (Refereed)
    Abstract [en]

    A new way of producing rigid or semi-rigid foams from vital wheat gluten using a freeze-drying process is reported. Water/gluten-based mixtures were frozen and freeze-dried. Different foam structures were obtained by varying the mixing process and wheat gluten concentration, or by adding glycerol or bacterial cellulose nanofibers. MIP revealed that the foams had mainly an open porosity peaking at 93%. The average pore diameter ranged between 20 and 73 mm; the sample with the highest wheat gluten concentration and no plasticizer had the smallest pores. Immersion tests with limonene revealed that the foams rapidly soaked up the liquid. An especially interesting feature of the low-wheat-concentration foams was the "in situ'' created soft-top-rigid-bottom foams.

  • 113.
    Bohn Lima, Raquel
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Establishment of ligning and other bio-renewable materials as fuels and material developments for better performance for fuel cell technology2014Doctoral thesis, comprehensive summary (Other academic)
  • 114.
    Bor, Yasemin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Alin, Jonas
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Hakkarainen, Minna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Electrospray Ionization-Mass Spectrometry Analysis Reveals Migration of Cyclic Lactide Oligomers from Polylactide Packaging in Contact with Ethanolic Food Simulant2012In: Packaging technology & science, ISSN 0894-3214, E-ISSN 1099-1522, Vol. 25, no 7, p. 427-433Article in journal (Refereed)
    Abstract [en]

    Electrospray ionization-mass spectrometry analysis revealed rapid migration of cyclic oligomers from polylactide (PLA) packaging when stored in contact with 96% ethanol. The mass losses in contact with water, 3% acetic acid, 10% ethanol and isooctane were 3 to 5 times smaller and no migration of cyclic oligomers was observed. The presence of cyclic oligomers in the original PLA films and their solubility in ethanol, thus, explains the rapid mass loss for PLA in contact with ethanolic food simulant. On prolonged ageing no further mass loss was observed in 96% ethanol, whereas mass loss in aqueous food simulants increased because of hydrolysis of PLA matrix or the cyclic oligomers to water-soluble linear products. The mass losses were generally somewhat smaller for the stereocomplex material compared with the poly-l-lactide materials. Similar trend was observed for solvent uptakes, which is easily explained by the higher degree of crystallinity and stronger secondary interactions in the stereocomplex material. The use of ethanol as a fatty food simulant for PLA materials could, thus, lead to overestimation of the overall migration values.

  • 115. Bosmans, Toon J.
    et al.
    Stepan, Agnes M.
    Toriz, Guillermo
    Renneckar, Scott
    Karabulut, Erdem
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Gatenholm, Paul
    Assembly of Debranched Xylan from Solution and on Nanocellulosic Surfaces2014In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 15, no 3, p. 924-930Article in journal (Refereed)
    Abstract [en]

    This study focused on the assembly characteristics of debranched xylan onto cellulose surfaces. A rye arabinoxylan polymer with an initial arabinose/xylose ratio of 0.53 was debranched with an oxalic acid treatment as a function of time. The resulting samples contained reduced arabinose/xylose ratios significantly affecting the molecular architecture and solution behavior of the biopolymer. With this treatment, an almost linear xylan with arabinose DS of only 0.04 was obtained. The removal of arabinose units resulted in the self-assembly of the debranched polymer in water into stable nanoparticle aggregates with a size around 300 nm with a gradual increase in crystallinity of the isolated xylan. Using quartz crystal microbalance with dissipation monitoring, the adsorption of xylan onto model cellulose surfaces was quantified. Compared to the nonmodified xylan, the adsorption of debranched xylan increased from 0.6 to 5.5 mg m(-2). Additionally, adsorption kinetics suggest that the nanoparticles rapidly adsorbed to the cellulose surfaces compared to the arabinoxylan. In summary, a control of the molecular structure of xylan influences its ability to form a new class of polysaccharide nanoparticles in aqueous suspensions and its interaction with nanocellulose surfaces.

  • 116.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Johansson, Mats
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Bionanocomposites reinforcedwith cellulose nanofibrils compatibilized through covalent grafting or physisorption of PCL –a comparative studyManuscript (preprint) (Other academic)
  • 117.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Javakhishvili, Irakli
    Technical University of Denmark.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Hvilsted, Søren
    Technical University of Denmark.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Preparation and evaluation of triblock copolymers based on poly(2-(dimethylamino)ethyl methacrylate) and poly(epsilon-caprolactone)2013In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 245, p. 613-POLY-Article in journal (Other academic)
    Abstract [en]

    In this work, the preparation of two block copolymers based on poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(ε-caprolactone) (PCL) has been conducted, creating the triblock copolymers PDMAEMA-b-PCL-b-PDMAEMA and PCL-b-PDMAEMA-b-PCL. The PDMAEMA-part was then quaternized, to give polyelectrolytes with either one or two charged block(s). Subsequently, differences in properties were studied in the solid state, in solution and in water dispersion with techniques including differential scanning calorimetry, size exclusion chromatography and dynamic light scattering.

  • 118.
    Bruce, Carl
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Nilsson, Camilla
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Paper sheets and laminates based on PCL- and PLLA-grafted fibers2011Conference paper (Refereed)
  • 119.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Nilsson, Camilla
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Paper-sheet biocomposites based on wood pulp grafted with poly(ε-caprolactone)Manuscript (preprint) (Other academic)
  • 120.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Nilsson, Camilla
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Paper-sheet biocomposites based on wood pulp grafted with poly(epsilon-caprolactone)2015In: Journal of Applied Polymer Science, ISSN 0021-8995, E-ISSN 1097-4628, Vol. 132, no 23, article id 42039Article in journal (Refereed)
    Abstract [en]

    Kraft pulp fibers were used as substrates for the grafting of poly(epsilon-caprolactone) (PCL) from available hydroxyl groups through ring-opening polymerization, targeting three different chain lengths (degree of polymerization): 120, 240, and 480. In a paper-making process, paper-sheet biocomposites composed of grafted fibers and neat pulp fibers were prepared. The paper sheets possessed both the appearance and the tactility of ordinary paper sheets. Additionally, the sheets were homogenous, suggesting that PCL-grafted fibers and neat fibers were compatible, as demonstrated by both Fourier transform infrared spectroscopy microscopy and through dye-labeling of the PCL-grafted fibers. Finally, it was shown that the paper-sheet biocomposites could be hot-pressed into laminate structures without the addition of any matrix polymer; the adhesive joint produced could even be stronger than the papers themselves. This apparent and sufficient adhesion between the layers was thought to be due to chain entanglements and/or co-crystallization of adjacent grafted PCL chains within the different paper sheets. (c) 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 42039.

  • 121.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Utsel, Simon
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Javakhishvili, Irakli
    Technical University of Denmark.
    Pettersson, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Hvilsted, Søren
    Technical University of Denmark.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Preparation and evaluation of well-defined di- and triblock copolymers based on poly[2-(dimethylamino)ethyl methacrylate] and poly(ε-caprolactone)2014In: ACS National Meeting, 2014Conference paper (Refereed)
    Abstract [en]

    In this work, di- and triblock copolymers based on poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) and poly(ε-caprolactone) (PCL) have been prepared. The PDMAEMA length was kept constant for both di- and triblock copolymers, while in the diblock copolymers the PCL length was varied in three different lengths, yielding three separate block copolymers. For the triblock blockcopolymers, on the other hand, also the PCL blocks were of the same length yielding one ABA- and one BAB-type block copolymer. In the next step, the PDMAEMA-part was quaternized to yield polyelectrolytes with either one or two charged block(s). In the final step, difference in adsorption behavior onto a negatively charged cellulose surface and subsequent alteration of surface properties was investigated. Overall, the polymers were evaluated in solid state, in solution, in water dispersion, and on cellulose surfaces with techniques including differential scanning calorimetry, size exclusion chromatography, dynamic light scattering and quartz crystal microbalance.

  • 122.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Utsel, Simon
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Larsson, Emma
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Carlmark, Anna
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Malmström, Eva
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    A comparative study of covalent grafting and physical adsorption of PCL onto cellulose2012Conference paper (Refereed)
    Abstract [en]

    A growing concern for the environment has, in the past years, directed the research towards a bigger focus on new “greener” materials, such as cellulose-reinforced options. Cellulose is the most abundant organic raw material in the world and it is a versatile material. However, to be able to use it in applications where it is not inherently compatible, a modification is often necessary.1-3 One common method to achieve this modification is to graft polymers onto/from the cellulose chain. This can change the inherent properties of cellulose to attain new properties, such as dimensional stability and water repellency.3 In addition to this, it has been shown that polyectrolytes can be physiosorbed onto charged surfaces.4 Due to this, it is possible to physically modify cellulose by adsorbing a polymer through electrostatic interactions instead of attaching it with a covalent bond.5

    However, a more detailed investigation concerning differences of covalent and physical attachment of poly(ε-caprolactone) (PCL) onto cellulose, has to the author’s best knowledge not been performed. Therefore, this project aims to compare these two techniques. Covalently bonded PCL was grafted by surface-initiated ring opening polymerization (SI-ROP) from the cellulose. For the adsorption approach, a block copolymer consisting of PCL and a shorter segment of poly(di(methylamino)ethyl methacrylate) (PDMAEMA) was made combining ROP and atom transfer radical polymerization (ATRP). The PDMAEMA-part was then quaternized, which resulted in a cationically charged chain – a polyelectrolyte. This can then be used as an electrostatic linker allowing the PDMAEMA-PCL copolymer to be adsorbed onto the negatively charged cellulose model surface. Finally, differences between the two approaches are evaluated regarding for example surface coverage and grafting/physiosorption efficiency investigated with techniques such as atomic force microscopy (AFM).

  • 123.
    Bruce, Carl
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Utsel, Simon
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.
    Larsson, Emma
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Carlmark, Anna
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Preparation and evaluation of a block copolymer compatibilizer for biocomposite applications2012Conference paper (Refereed)
    Abstract [en]

    In this study, a comparison between covalent grafting and physical adsorption of PCL onto a nanocellulose model surface was conducted. For the covalent attachment, surface-initiated ring-opening polymerization (SI-ROP) was performed. For the physical attachment, a charged block copolymer consisting of PCL and quaternized PDMAEMA was synthesized by ROP and ATRP, and adsorbed to the cellulose. Finally, differences in between the two substrates were investigated with techniques such as AFM.

  • 124.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Utsel, Simon
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Larsson, Emma
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    A comparative study of covalent grafting and physical adsorption of PCL onto cellulose2011Conference paper (Refereed)
    Abstract [en]

    In the past years, a growing concern for the environment has forced the research to focus more on new “greener” materials. The most abundant organic raw material in the world is cellulose. This, in combination with the versatility of the material, makes it interesting as a green option in various applications. However, to be able to take advantage of all characteristics possessed by cellulose, i.e., use it in applications where it is not inherently compatible, modification is often necessary.1-3 One common method used for modifying cellulose is grafting of polymers onto/from the cellulose chain. This offers a way of changing the inherent properties of cellulose to attain new properties, such as dimensional stability and water repellency.3

    Additionally, it has been shown that polyectrolytes can be physiosorbed onto charged surfaces.4 This has made it possible to physically modify cellulose by adsorbing a polymer through electrostatic interactions instead of attaching it with a covalent bond.5 However, a more detailed investigation concerning the differences, such as surface coverage and grafting/physiosorption efficiency, between a covalent and physical attachment of a polymer has to the author’s best knowledge earlier not been performed. Therefore, this project aims to compare these two techniques. A block copolymer consisting of poly(ε-caprolactone) (PCL) and poly(di(methylamino)ethyl methacrylate) (PDMAEMA) is made, see figure 1 for 1H-NMR-spectrum.

    Figure 1. The 1H-NMR-spectrum of PCL-block-PDMAEMA (in CDCl3).

    The PDMAEMA-part is then quaternized (figure 2), which results in a charged chain – a polyelectrolyte.

    Figure 2.The quaternization of the PDMAEMA block to obtain cationic charges.

    The charges allow for the PDMAEMA-PCL copolymer to be adsorbed onto a cellulose surface. Finally, to evaluate and compare the differences between the covalent and the physical surface modification, regarding for example surface coverage, grafting/physiosorption efficiency, adhesion and matrix compatibility, various characterization methods are employed: fourier transform infrared spectroscopy (FTIR), contact angle measurements (CA), micro adhesion measurement apparatus (MAMA), force measurements using atomic force microscopy (AFM) and macroscopic peel tests using dynamical mechanical analysis (DMA) or Instron.

    Figure 3. A schematic drawing of covalent attachment and physical adsorption of PCL onto cellulose.

    Further work after preparation of fibres may include such steps as making of fiber-reinforced composites, out of both chemically and physically modified fibres, where for example differences concerning mechanical properties would be investigated.

    References

    (1) Lönnberg, H.; Fogelström, L.; Berglund, L.; Malmström, E.; Hult, A. European Polymer Journal 2008, 44, 2991.

    (2) Lönnberg, H.; Zhou, Q.; Brumer, H., 3rd; Teeri Tuula, T.; Malmström, E.; Hult, A. Biomacromolecules 2006, 7, 2178.

    (3) Roy, D.; Semsarilar, M.; Guthrie, J. T.; Perrier, S. Chemical Society Reviews 2009, 38, 2046.

    (4) Decher, G.; Hong, J. D. Berichte der Bunsen-Gesellschaft 1991, 95, 1430.

    (5) Utsel, S.; Carlmark, A.; Pettersson, T.; Bergström, M.; Malmström, E.; Wågberg, L. Abstracts of Papers, 241st ACS National Meeting & Exposition, Anaheim, CA, United States, March 27-31, 2011 2011, CELL.

  • 125.
    Bruce, Carl
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Utsel, Simon
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.
    Larsson, Emma
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Fogelström, Linda
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Comparative study of covalent grafting and physical adsorption of PCL onto cellulose2012Conference paper (Refereed)
    Abstract [en]

    In this work, an investigation concerning differences between covalent and physical attachment of poly(ε-caprolactone) (PCL) to a nanocellulose modell surface was conducted. For the covalent attachment, ring-opening polymerization (ROP) was performed using the “grafting-from” approach, building the polymer from the surface. For the physical attachment, a block copolymer consisting of PCL and poly(di(methylamino)ethyl methacrylate) (PDMAEMA) was made combining ROP and atom transfer radical polymerization (ATRP). The PDMAEMA-part was then quaternized, which resulted in a charged chain – a polyelectrolyte. The charges allow for the PDMAEMA-PCL copolymer to be adsorbed onto the nanocellulose modell surface. The length of the PDMAEMA-part was kept constant (DP=20), and the length of PCL was varied (DP=150, 300, 600) for both the covalently attached polymer and for the copolymer. Finally, differences between the two approaches were evaluated regarding for example surface coverage and grafting/physiosorption efficiency investigated with techniques such as atomic force microscopy.

  • 126.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Utsel, Simon
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Larsson, Emma
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Malmström Jonsson, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Comparative study of covalent grafting and physical adsorption of PCL onto cellulose2012In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 243Article in journal (Other academic)
  • 127.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Utsel, Simon
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Pettersson, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Physical Tuning of Cellulose-Polymer Interactions Utilizing Cationic Block Copolymers Based on PCL and Quaternized PDMAEMA2013Conference paper (Refereed)
    Abstract [en]

    In this study, the aim was to prepare and evaluate a block copolymer that can be used as a compatibilizer in cellulose fiber-reinforced biocomposites. It is an amphiphilic block copolymer consisting of poly(ε-caprolactone) (PCL), prepared with  ring-opening polymerization (ROP)1, and a shorter segment of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) synthesized with atom transfer radical polymerization (ATRP)2. The PDMAEMA-part was prepared in one single length, while the PCL-part was varied in three different lengths. In the last synthesis step the PDMAEMA-part was quaternized, turning it into a cationically charged chain – a polyelectrolyte. The block copolymers were then able to form cationic micelles in water, from where they can adsorb, under mild conditions, to anionic surfaces such as silicon oxide and cellulose-model surfaces. A similar concept has been investigated earlier in a system fully prepared with ATRP3. Additionally, physical adsorption of micelles is a milder approach of attaching a polymer to a cellulose surface compared to more traditional covalent attachment4, making it an interesting option to use in industry. After adsorption, the surface had a more hydrophobic character shown with contact angle measurements, and with AFM force measurements, it was demonstrated that there is a clear entanglement behavior obtained between the block copolymers and a PCL surface at about 60 °C, which is of importance for the information regarding the adhesive interface in a future biocomposite.

  • 128.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Utsel, Simon
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Pettersson, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Physical Tuning of Cellulose-Polymer Interactions Utilizing Cationic Block Copolymers Based on PCL and Quaternized PDMAEMA2013Conference paper (Refereed)
    Abstract [en]

    In this study, the aim was to prepare and evaluate a block copolymer that can be used as a compatabilizer in cellulose fiber-reinforced biocomposites. It as an amphiphilic block copolymer consisting of poly(ε-caprolactone) (PCL), made with  ring-opening polymerization (ROP), and a shorter segment of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) that was synthesized with atom transfer radical polymerization (ATRP). The PDMAEMA-part was made in one single length, while the PCL-part was varied in three different lengths; in total were three block copolymers prepared. In the last step of the synthesis, the PDMAEMA-part was quaternized that turns it into a cationically charged chain – a polyelectrolyte. The block copolymers were then able to form cationic micelles in water, from where they can adsorb, under mild conditions, to anionic surfaces such as silicon oxide and cellulose-model surfaces. This provides the surface with a more hydrophobic character shown with contact angle measurements. Finally, with atomic force microscopy (AFM) force measurements, it was demonstrated that there is a clear entanglement behavior obtained between the block copolymers and a PCL surface at about 60 °C, which is of importance for the information regarding the adhesive interface in a future biocomposite.

  • 129.
    Bruce, Carl
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Utsel, Simon
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Pettersson, Torbjörn
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Larsson, Emma
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Fogelström, Linda
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Fibre Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Preparation and evaluation of a block copolymer compatibilizer for biocomposite applications2012Conference paper (Refereed)
    Abstract [en]

    In this study, the concept of using a free polymer as a compatibilzer in biocomposite applications has been evaluated with focus on the polymer poly(ɛ-caprolactone) (PCL), commonly used in conventional grafting onto/from cellulose. A block copolymer consisting of PCL and a shorter segment of poly(di(methylamino)ethyl methacrylate) (PDMAEMA) was made combining ring-opening polymerization (ROP) and atom transfer radical polymerization (ATRP). The length of the PDMAEMA-part was kept constant, and the PCL-part was varied in three different lengths, yielding three separate block copolymers. As a final step, the PDMAEMA-part was quaternized, which resulted in cationically charged chains –polyelectrolytes. The charged part could then be used as an electrostatic linker allowing the PDMAEMA-PCL copolymer to be adsorbed onto negatively charged cellulose model surfaces. Finally, these cellulose model surfaces were evaluated regarding for example amount of polymer adsorbed and hydrophobic character, investigated with techniques such as quartz crystal microbalance (QCM) and contact angle measurements.

  • 130.
    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.

  • 131.
    Brännström, Sara
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Finnveden, Maja
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Johansson, Mats
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Martinelle, Mats
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Industrial Biotechnology.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Itaconate based polyesters: Selectivity and performance of esterification catalysts2018In: European Polymer Journal, ISSN 0014-3057, E-ISSN 1873-1945, Vol. 103, p. 370-377Article in journal (Refereed)
    Abstract [en]

    The performance of different esterification catalysts was studied for the use in synthesis of renewable polyesters from dimethyl itaconate (DMI), dimethyl succinate (DMS) and 1,4-butanediol (BD). Itaconic acid and derivatives such as DMI are interesting monomers because of their multiple functionalities and previous work has shown great potential. However, the multiple functionalities also pose challenges to avoid side reactions such as thermally initiated, premature, radical crosslinking and/or isomerization of the 1,1-disubstituted unsaturation. Additionally, the two carboxylic acids have inherently different reactivity. One key factor to control reactions with IA is to understand the performance of different catalysts. In this study, six esterification catalysts were investigated; immobilized Candida antarctica lipase B (CalB), titanium(IV)butoxide (Ti(OBu)4), p-toluenesulfonic acid (pTSA), sulfuric acid (H2SO4), 1,8-diazabicycloundec-7-ene (DBU), and 1,5,7-triazabicyclodec-5-ene (TBD). CalB and Ti(OBu)4 were selected for further characterization with appreciable differences in catalytic activity and selectivity towards DMI. CalB was the most effective catalysts and was applied at 60 °C while Ti(OBu)4 required 160 °C for a reasonable reaction rate. CalB was selective towards DMS and the non-conjugated side of DMI, resulting in polyesters with itaconate-residues mainly located at the chain ends, while Ti(OBu)4 showed low selectivity, resulting in polyesters with more randomly incorporated itaconate units. Thermal analysis of the polyesters showed that the CalB-catalyzed polyesters were semi-crystalline, whereas the Ti(OBu)4-catalyzed polyesters were amorphous, affirming the difference in monomer sequence. The polyester resins were crosslinked by UV-initiated free radical polymerization and the material properties were evaluated and showed that the crosslinked materials had similar material properties. The films from the polyester resins catalyzed by CalB were furthermore completely free from discoloration whereas the film made from the polyester resins catalyzed with Ti(OBu)4 had a yellow color, caused by the catalyst. Thus, it has been shown that CalB can be used to attain sustainable unsaturated polyesters resins for coating applications, exhibiting equally good properties as resins obtained from traditional metal-catalysis.

  • 132.
    Brännström, Sara
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Johansson, Mats
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Malmström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Enzymatically Synthesized Vinyl Ether-Disulfide Monomer Enabling an 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. 1308-1316Article 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 Rhodamine-VE by radical UV-initiation

  • 133.
    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 Chemistrytoward 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.

  • 134. Buchert, Johanna
    et al.
    Bergnor, Elisabeth
    Lindblad, Gunnar
    Viikari, Liisa
    Ek, Monica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Significance of xylan and glucomannan in the brightness reversion of kraft pulps1997In: TAPPI Journal, ISSN 0734-1415, Vol. 80, no 6, p. 165-171Article in journal (Refereed)
    Abstract [en]

    The brightness reversion of kraft pulps is caused by the presence of residual lignin, chlorinated extractives, or oxidized carbohydrates. The effect of hemicellulose content, i.e., xylan (I) and glucomannan (II), on the thermal stability of modern bleached kraft pulps was investigated. Different O-delignified hard- and softwood kraft pulps were bleached with different bleaching sequences contg. ClO2, H2O2, or O3. Hemicellulose-degrading enzymes, i.e., xylanase or mannanase, were used for selective removal of the resp. hemicellulose from the pulps, and the role of partially removed I and II on the brightness stability of these pulps was studied. Because of the structure of kraft I, enzymic removal of I also resulted in a decreased carboxyl group content in the pulps, whereas II removal did not affect the carboxyl group content. By decreasing the carboxyl groups in the pulps in conjunction with I removal, the thermal aging of the pulps was significantly decreased. The role of II was less significant. Thus, the uronic acids present in the pulp participate in the brightness reversion of kraft pulps.

  • 135. Buchert, Johanna
    et al.
    Bergnor, Elisabeth
    Lindblad, Gunnar
    Viikari, Liisa
    Ek, Monica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    The role of xylan and glucomannan in yellowing of kraft pulps.1995In: Proceedings 8th Int. Symp. Wood Pulp. Chem., 1995, p. 43-48Conference paper (Refereed)
    Abstract [en]

    The effects of xylan and glucomannan on the thermal stability of unbleached, partially bleached, and fully bleached pine and birch kraft pulps were studied.  The choice of bleaching chems. strongly affected the brightness reversion.  Compared with hydrogen peroxide or chlorine dioxide, bleaching with ozone reduced the amt. of carboxyl groups and subsequently the pc-nos. of oxygen-delignified pulps.  Xylan removal reduced also the amt. of carboxyl groups in the pulps and this was reflected in improved brightness stability whereas glucomannan removal had no effect.  Thus, the uronic acids bound to pulp xylan were found to participate in the brightness reversion of kraft pulps.

  • 136. Buchert, Johanna
    et al.
    Tenkanen, Maija
    Ek, Monica
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Wood Chemistry and Pulp Technology.
    Teleman, Anita
    Vuorinen, Tapani
    Effect of pulping and bleaching on pulp carbohydrates and technical properties.1996In: Proceedings Int. Pulp Bleaching, 1996, p. 39-42Conference paper (Refereed)
    Abstract [en]

    Pulping and bleaching have a profound effect on the carbohydrate chem. of kraft pulps.  The chem. structure of xylan is modified due to the conversion of methylglucuronic acid side groups to hexenuronic acid side groups.  Pulping conditions strongly affect the amt. of hexenuronic acid present in the pulp and subsequently modified kraft pulps have different carboxyl group profiles as compared with conventionally cooked pulps.  Due to its reactivity, hexenuronic acid is readily degraded when chlorine dioxide or ozone are used as bleaching chems.  However, TCF-pulps bleached with peroxide and oxygen contain high amts. of hexenuronic acid.  Thus, depending on the pulping and bleaching method, the quality and quantity of carboxylic acids in different types of pulps varies significantly.  The differences in the uronic acid content are in turn reflected in the macroscale properties of the pulps, such as brightness stability.       

  • 137.
    Burman, Lina
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Albertsson, Ann-Christine
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Hakkarainen, Minna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Indicator products and chromatographic fingerprinting: New tools for degradation state and lifetime estimation2008In: CHROMATOGRAPHY FOR SUSTAINABLE POLYMERIC MATERIALS: RENEWABLE, DEGRADABLE AND RECYCLABLE, Berlin: Springer Verlag , 2008, Vol. 211, p. 1-22Chapter in book (Refereed)
    Abstract [en]

    The demands on polymeric products are growing both with respect to their function and purity. There is a need for new high-throughput characterisation tools for rapid quality control and evaluation of materials. Precise control over degradation rate and service-life are also prerequisites for successful use of degradable polymers in an increasing number of applications. The chromatographic fingerprinting and indicator product concepts, presented in the current paper, are novel and attractive alternatives for rapid evaluation of the product quality, degradability, durability and service-life. The sensitivity of these techniques allows for detection of small initial changes in the materials and signs of early degradation. The possible applications include evaluation of different pro-oxidants or antioxidants, optimisation of processing parameters, evaluation of long-term properties or storage stability and lifetime prediction. The same principal could also be applied to process control and monitoring, acceptance or rejection of raw materials, intermediate and final products. The usefulness of indicator products and chromatographic fingerprinting is shown for estimation of the degradation state of degradable polyethylene. in addition, chromatographic fingerprinting together with multivariate data analysis is utilised to classify degradable polyethylene materials based on their incorporated pro-oxidant systems.

  • 138.
    Butchosa, Núria
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Biocomposites.
    Zhou, Qi
    KTH, School of Biotechnology (BIO), Glycoscience. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Water redispersible cellulose nanofibrils adsorbed with carboxymethyl cellulose2014In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 21, no 6, p. 4349-4358Article in journal (Refereed)
    Abstract [en]

    Cellulose nanofibrils (CNFs) are difficult to redisperse in water after they have been completely dried due to the irreversible agglomeration of cellulose during drying. Here, we have developed a simple process to prepare water-redispersible dried CNFs by the adsorption of small amounts of carboxymethyl cellulose (CMC) and oven drying. The adsorption of CMC onto CNFs in water suspensions at 22 and 121 °C was studied, and the adsorbed amount of CMC was measured via conductimetric titration. The water-redispersibility of dried CNFs adsorbed with different amounts of CMC was characterized by sedimentation test. Above a critical threshold of CMC adsorption, i.e. 2.3 wt%, the oven dried CNF–CMC sample was fully redispersible in water. The morphology, rheological, and mechanical properties of water-redispersed CNF–CMC samples were investigated by field emission scanning electron microscopy, viscosity measurement, and tensile test, respectively. The water-redispersed CNFs preserved the original properties of never dried CNFs. This new method will facilitate the production, transportation and storage, and large-scale industrial applications of CNFs.

  • 139.
    Bäckström, Eva
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Odelius, Karin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Hakkarainen, Minna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Designed from Recycled: Turning Polyethylene Waste to Covalently Attached Polylactide Plasticizers2019In: ACS SUSTAINABLE CHEMISTRY & ENGINEERING, ISSN 2168-0485, Vol. 7, no 12, p. 11004-11013Article in journal (Refereed)
    Abstract [en]

    High-density polyethylene (HDPE) waste was successfully feedstock recycled, and the obtained chemicals were utilized for synthesis of plasticizers for polylactide (PLA). First, an effective route to recycle HDPE through a microwave-assisted hydrothermal process was established. This process led to selective degradation of HDPE to a few well-defined chemicals, namely, succinic, glutaric, and adipic acid. A model plasticizer was synthesized from the same composition of dicarboxylic acids, 1,4-butanediol, and crotonic acid. The function of crotonic acid was to produce oligomers with crotonate end groups for coupling the plasticizer to PLA main chain. The plasticizer was then blended with or coupled to PLA by a reactive extrusion process. Adding the plasticizer to PLA decreased the T-g and increased the strain at break, thus reducing the brittleness of the films. The addition of 20% (w/w) grafted plasticizer increased the strain at break of PLA from 6 to 156% and decreased the T-g by 15 degrees C compared with neat PLA. Finally, to verify the concept, a plasticizer was also synthesized from the dicarboxylic acid product mixture obtained from the feedstock recycling of HDPE. The recycled grafted plasticizer increased the strain at break of PLA to 142% and reduced the T-g by 10 degrees C. A promising route for designing from recycled feedstock, turning HDPE waste to PLA plasticizers, was thus demonstrated.

  • 140. Cantu-Jungles, Thaisa Moro
    et al.
    Ruthes, Andrea Caroline
    KTH, School of Biotechnology (BIO), Glycoscience. Universidade Federal do Paraná, Brazil.
    El-Hindawy, Marwa
    Moreno, Roberta Barbara
    Zhang, Xiaowei
    Cordeiro, Lucimara M. C.
    Hamaker, Bruce R.
    Iacomini, Marcello
    In vitro fermentation of Cookeina speciosa glucans stimulates the growth of the butyrogenic Clostridium cluster XIVa in a targeted way2018In: Carbohydrate Polymers, ISSN 0144-8617, E-ISSN 1879-1344, Vol. 183, p. 219-229Article in journal (Refereed)
    Abstract [en]

    Dietary fiber chemical and physical structures may be critical to the comprehension of how they may modulate gut bacterial composition. We purified insoluble polymers from Cookeina speciosa, and investigated its fermentation profile in an in vitro human fecal fermentation model. Two glucans, characterized as a (1 -> 3),(1 -> 6)-linked and a (1 -> 3)-linked beta-D-glucans were obtained. Both glucans were highly butyrogenic and propiogenic, with low gas production, during in vitro fecal fermentation and led to distinct bacterial shifts if compared to fructooligosaccharides. Specific increases in Bacteroides uniformis and genera from the Clostridium cluster XIVa, such as butyrogenic Anaerostipes and Roseburia were observed. The (1 -> 3)-linked beta-D-glucan presented a faster fermentation profile compared to the branched (1 -> 3),(1 -> 6)-linked beta-D-glucan. Our findings support the view that depending on its fine chemical structure, and likely its insoluble nature, these dietary fibers can be utilized to direct a targeted promotion of the intestinal microbiota to butyrogenic Clostridium cluster XIVa bacteria.

  • 141.
    Cappel, Ute B.
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Liu, Peng
    KTH, School of Industrial Engineering and Management (ITM), Materials Science and Engineering, Applied Material Physics. KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Johansson, Fredrik O. L.
    Uppsala Univ, Div Mol & Condensed Matter Phys, Dept Phys & Astron, SE-75120 Uppsala, Sweden..
    Philippe, Bertrand
    Uppsala Univ, Div Mol & Condensed Matter Phys, Dept Phys & Astron, SE-75120 Uppsala, Sweden..
    Giangrisostomi, Erika
    Helmholtz Zentrum Berlin GmbH, Inst Methods & Instrumentat Synchrotron Radiat Re, Albert Einstein Str 15, D-12489 Berlin, Germany..
    Ovsyannikov, Ruslan
    Helmholtz Zentrum Berlin GmbH, Inst Methods & Instrumentat Synchrotron Radiat Re, Albert Einstein Str 15, D-12489 Berlin, Germany..
    Lindblad, Andreas
    Uppsala Univ, Div Mol & Condensed Matter Phys, Dept Phys & Astron, SE-75120 Uppsala, Sweden..
    Kloo, Lars
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Gardner, James M.
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD.
    Rensmo, Hakan
    Uppsala Univ, Div Mol & Condensed Matter Phys, Dept Phys & Astron, SE-75120 Uppsala, Sweden..
    Electronic Structure Characterization of Cross-Linked Sulfur Polymers2018In: ChemPhysChem, ISSN 1439-4235, E-ISSN 1439-7641, Vol. 19, no 9, p. 1041-1047Article in journal (Refereed)
    Abstract [en]

    Cross-linked polymers of elemental sulfur are of potential interest for electronic applications as they enable facile thin-film processing of an abundant and inexpensive starting material. Here, we characterize the electronic structure of a cross-linked sulfur/diisopropenyl benzene (DIB) polymer by a combination of soft and hard X-ray photoelectron spectroscopy (SOXPES and HAXPES). Two different approaches for enhancing the conductivity of the polymer are compared: the addition of selenium in the polymer synthesis and the addition of lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) during film preparation. For the former, we observe the incorporation of Se into the polymer structure resulting in a changed valence-band structure. For the latter, a Fermi level shift in agreement with p-type doping of the polymer is observed and also the formation of a surface layer consisting mostly of TFSI anions.

  • 142.
    Carlborg, Carl Fredrik
    et al.
    KTH, School of Electrical Engineering (EES), Microsystem Technology (Changed name 20121201).
    Haraldsson, Tommy
    KTH, School of Electrical Engineering (EES), Microsystem Technology (Changed name 20121201).
    Öberg, Kim
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Malkoch, Michael
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    van der Wijngaart, Wouter
    KTH, School of Electrical Engineering (EES), Microsystem Technology (Changed name 20121201).
    BEYOND PDMS:: OFF-STOCHIOMETRY THIOL-ENE BASED SOFT LITHOGRAPHY FOR RAPID PROTOTYPING OF MICROFLUIDIC DEVICES2010In: 14th International Conference on Miniaturized Systems for Chemistry and Life Sciences (micro TAS 2010), 2010, p. 70-72Conference paper (Refereed)
    Abstract [en]

    We present an easy to use, rapid fabrication platform for microfluidic systems, based on micro-molding of novel thiolene based polymer formulations. The novel fabrication platform addresses major drawbacks of PDMS by allowing large freedom in material and surface properties, including: (photo)patterning of stable surface modifications, bonding without plasma treatment, rapid UV or thermal curing, variable E-modulus, minimized leaching of uncured components [1] and suppressed non-specific binding of biomolecules [2]. This process is potentially suited for both rapid prototyping in the laboratory and medium-scale commercial production, bridging the “development gap”.

  • 143.
    Carlmark, Anna
    KTH, Superseded Departments, Polymer Technology.
    Atom transfer radical polymerization from multifunctional substrates2002Licentiate thesis, comprehensive summary (Other scientific)
    Abstract [en]

    Atom transfer radical polymerization (ATRP) has proven to be a powerful technique to obtain polymers with narrow polydispersities and controlled molecular weight. It also offers control over chain-ends. The technique is the most studied and utilized of thecontrolled/”living” radical polymerization techniques since a large number of monomerscan be polymerized under simple conditions. ATRP can be used to obtain polymer graftsfrom multifunctional substrates. The substrates can be either soluble (i. e. based ondendritic molecules) or insoluble (such as gold or silicon surfaces). The large number ofgrowing chains from the multifunctional substrates increases the probability of inter-and intramolecular reactions. In order to control these kinds of polymerizing systems, andsuppress side-reactions such as termination, the concentration of propagating radicalsmust be kept low. To elaborate such a system a soluble multifunctional substrate, based on 3-ethyl-3-(hydroxymethyl)oxetane, was synthesized. It was used as a macroinitiatorfor the atom transfer radical polymerisation of methyl acrylate (MA) mediated byCu(I)Br and tris(2-(dimethylamino)ethyl)amine (Me6-TREN) in ethyl acetate at room temperature. This yielded a co-polymer with a dendritic-linear architecture. Since mostsolid substrates are sensitive to the temperatures at which most ATRP polymerisations are performed, lowering the polymerization temperatures are preferred. ATRP at ambienttemperature is always more desirable since it also suppresses the formation of thermally formed polymer. The macroinitiator contained approximately 25 initiating sites, which well mimicked the conditions on a solid substrate. The polymers had low polydispersity and conversions as high as 65% were reached without loss of control. The solid substrateof choice was cellulose fibers that prior to this study not had been grafted through ATRP.As cellulose fibers a filter paper, Whatman 1, was used due to its high cellulose content.The hydroxyl groups on the surface was first reacted with 2-bromoisobutyryl bromidefollowed by grafting of MA. Essentially the same reaction conditions were used that hadbeen elaborated from the soluble substrate. The grafting yielded fibers that were very hydrophobic (contact angles>100°). By altering the sacrificial initiator-to-monomer ratiothe amount of polymer that was attached to the surface could be tailor. PMA with degreesof polymerization (DP’s) of 100, 200 and 300 were aimed. In order to control that thepolymerizations from the surface was indeed “living” a second layer of a hydrophilicmonomer, 2-hydroxymethyl methacrylate (HEMA), was grafted onto the surface. Thisdramatically changed the hydrophobic behavior of the fibers.

  • 144.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Coating Technology.
    Tailoring cellulose surfaces by controlled polymerization methods2013In: Macromolecular Chemistry and Physics, ISSN 1022-1352, E-ISSN 1521-3935, Vol. 214, no 14, p. 1539-1544Article in journal (Refereed)
    Abstract [en]

    Cellulose, with its excellent mechanical properties and low weight, would be highly advantageous to employ in bioplastics and biocomposites applications. However, to expand the utilization of cellulose beyond its traditional uses, a modification of the fiber surface is often a prerequisite. One approach is to graft polymer chains on the surface in order to compatibilize the fibers with a non-polar polymer matrix or to introduce functionalities. By exploiting controlled polymerization methods such as ATRP, RAFT, ROP, and ROMP, the surface of the fibers can be carefully tailored. Herein, an overview on controlled, heterogeneous grafting of cellulose fibers and fibrils employing both "grafting from" and "grafting to" methodologies is provided, focusing on the latest findings.

  • 145.
    Carlmark, Anna E
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Vestberg, Robert
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Malmström Jonsson, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Atom transfer radical polymerization of methyl acrylate from a multifunctional initiator at ambient temperature2002In: Polymer, ISSN 0032-3861, E-ISSN 1873-2291, Vol. 43, no 15, p. 4237-4242Article in journal (Refereed)
    Abstract [en]

    A multifunctional initiator for ATRP has been synthesized by reacting a hyperbranched polyether, based on 3-ethyl-3-(hydroxymethyl)oxetane, with 2-bromo-isobutyrylbromide. The macroinitiator contained approximately 25 initiating sites per molecule. It was used for the atom transfer radical polymerization of methyl acrylate mediated by Cu(I)Br and tris(2-(dimethylamino)ethyl)amine (Me-6-TREN) in ethyl acetate at room temperature. This yielded a co-polymer with a dendritic-linear architecture. The large number of growing chains from each macromolecule increases the probability of inter-and intramolecular reactions. In order to control these kinds of polymerizing systems and prevent them from forming a gel, the concentration of propagating radicals must be kept low. The polymerizations under these conditions were well controlled. When a ratio of initiating sites-to-catalyst of 1:0.05 was used, the polymers from all of the reactions had a low polydispersity, ranging from 1.1 to 1.4. None of the polymerizations under these conditions gave gelation. Monomer conversions as high as 65% were reached while maintaining control over the polymerization. (C) 2002 Elsevier Science Ltd. All rights reserved.

  • 146.
    Carlmark, Anna
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Atom transfer radical polymerization from cellulose fibers at ambient temperature2002In: Journal of the American Chemical Society, ISSN 0002-7863, E-ISSN 1520-5126, Vol. 124, no 6, p. 900-901Article in journal (Refereed)
    Abstract [en]

    Cellulose fibers have been successfully grafted with poly(methyl acrylate) using atom transfer radical polymerization, mediated by Me6-TREN and Cu(I)Br at ambient temperature. The initially hydrophilic cellulose was first modified by reacting the hydrozyl groups with 2-bromoisobutyryl bromide whereupon methyl acrylate was grafted from the surface. The resulting polymer-grafted papers were extremely hydrophobic, θa = 133°. FT-IR analysis indicates that the amount of grafted polymer can be controlled by adding sacrificial initiator to the polymerizing system. Size exclusion chromatography of the bulk polymer revealed narrow polydispersities and a molecular weight corresponding to the ratio [M]:[I].

  • 147.
    Carlsson, Linn
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Fall, Andreas
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Chaduc, Isabelle
    Wågberg, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Charleux, Bernadette
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    D'Agosto, Franck
    Lansalot, Muriel
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Modification of cellulose model surfaces by cationic polymer latexes prepared by RAFT-mediated surfactant-free emulsion polymerization2014In: Polymer Chemistry, ISSN 1759-9954, E-ISSN 1759-9962, Vol. 5, no 20, p. 6076-6086Article in journal (Refereed)
    Abstract [en]

    This paper presents the successful surface modification of a model cellulose substrate by the preparation and subsequent physical adsorption of cationic polymer latexes. The first part of the work introduces novel charged polymer nanoparticles constituted of amphiphilic block copolymers based on cationic poly(N,N-dimethylaminoethyl methacrylate-co-methacrylic acid) (P(DMAEMA-co-MAA)) as the hydrophilic segment, and poly(methyl methacrylate) (PMMA) as the hydrophobic segment. First, RAFT polymerization of N,N-dimethylaminoethyl methacrylate (DMAEMA) in water was performed at pH 7, below its pK(a). The simultaneous hydrolysis of DMAEMA led to the formation of a statistical copolymer incorporating mainly protonated DMAEMA units and some deprotonated methacrylic acid units at pH 7. The following step was the RAFT-mediated surfactant-free emulsion polymerization of methyl methacrylate (MMA) using P(DMAEMA-co-MAA) as a hydrophilic macromolecular RAFT agent. During the synthesis, the formed amphiphilic block copolymers self-assembled into cationic latex nanoparticles by polymerization-induced self-assembly (PISA). The nanoparticles were found to increase in size with increasing molar mass of the hydrophobic block. The cationic latexes were subsequently adsorbed to cellulose model surfaces in a quartz crystal microbalance equipment with dissipation (QCM-D). The adsorbed amount, in mg m(-2), increased with increasing size of the nanoparticles. This approach allows for physical surface modification of cellulose, utilizing a water suspension of particles for which both the surface chemistry and the surface structure can be altered in a well-defined way.

  • 148.
    Carlsson, Linn
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Ingverud, Tobias
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Blomberg, Hanna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Larsson, Per Tomas
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology. KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. Innventia AB, Sweden.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Surface characteristics of cellulose nanoparticles grafted by surface-initiated ring-opening polymerization of epsilon-caprolactone2015In: Cellulose (London), ISSN 0969-0239, E-ISSN 1572-882X, Vol. 22, no 2, p. 1063-1074Article in journal (Refereed)
    Abstract [en]

    In this study, surface-initiated ring-opening polymerization has been employed for the grafting of epsilon-caprolactone from cellulose nanoparticles, made by partial hydrolysis of cellulose cotton linters. A sacrificial initiator was employed during the grafting reactions, to form free polymer in parallel to the grafting reaction. The degree of polymerization of the polymer grafts, and of the free polymer, was varied by varying the reaction time. The aim of this study was to estimate the cellulose nanoparticle degree of surface substitution at different reaction times. This was accomplished by combining measurement results from spectroscopy and chromatography. The prepared cellulose nanoparticles were shown to have 3.1 (+/- 0.3) % of the total anhydroglucose unit content present at the cellulose nanoparticle surfaces. This effectively limits the amount of cellulose that can be targeted by the SI-ROP reactions. For a certain SI-ROP reaction time, it was assumed that the resulting degree of polymerization (DP) of the grafts and the DP of the free polymer were equal. Based on this assumption it was shown that the cellulose nanoparticle surface degree of substitution remained approximately constant (3-7 %) and seemingly independent of SI-ROP reaction time. We believe this work to be an important step towards a deeper understanding of the processes and properties controlling SI-ROP reactions occurring at cellulose surfaces.

  • 149.
    Carlsson, Linn
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Malmström, Eva
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Carlmark, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Surface-initiated ring-opening metathesis polymerisation from cellulose fibres2012In: POLYM CHEM-UK, ISSN 1759-9954, Vol. 3, no 3, p. 727-733Article in journal (Refereed)
    Abstract [en]

    In this study, cellulose fibres have been grafted utilizing surface-initiated ring-opening metathesis polymerisation (SI-ROMP). Initially, a Grubbs' type catalyst was immobilized onto filter paper whereafter SI-ROMP of norbornene was performed from the surface of the fibres at three different reaction temperatures, room temperature (RT), 0 degrees C and -18 degrees C, and for different reaction times. The evaluation of the grafted cellulose was performed by contact angle measurements, FT-Raman spectroscopy, FE-SEM and TGA. After the grafting, all samples were clearly hydrophobic with weight increases up to over 100%. The FT-Raman spectroscopy analysis showed significant structural changes after polymerization for cellulose substrates polymerized at 0 degrees C and RT, confirming that a polymer was grafted from the surface. FE-SEM images verified that these samples are covered by polynorbornene and that the fibrillar structure of the native cellulose disappeared. For the samples grafted at -18 degrees C, no significant changes were seen with these analysis methods. However, SI-ROMP appears to be a versatile method to modify cellulose fibres.

  • 150.
    Carosio, Federico
    et al.
    Politecn Torino, I-15121 Alessandria, Italy.
    Kochumalayil, Jose
    Cuttica, F.
    Camino, G.
    Berglund, Lars
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Biocomposites.
    Oriented Clay Nanopaper from Biobased Components Mechanisms for Superior Fire Protection Properties2015In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 7, no 10, p. 5847-5856Article in journal (Refereed)
    Abstract [en]

    The toxicity of the most efficient fire retardant additives is a major problem for polymeric Materials. Cellulose nanofiber (CNF)/clay nanocomposites, with unique brick-and-mortar structure and prepared by simple filtration, are characterized from the morphological point of view by scanning electron microscopy and X-ray diffraction. These nanocomposites have superior fire protection properties to Other clay nanocomposites and fiber composites. The Corresponding mechanisms are evaluated in terms of flammability (reaction to a flame) and cone calorimetry (exposure to heat flux). These two tests provide a wide spectrum characterization of fire protection properties in CNF/montmorrilonite (MTM) Materials. The morphology of the collected residues after flammability testing is investigated. In addition, thermal and thermo-oxidative stability are evaluated by thermogravimetric analyses performed in inert (nitrogen) and oxidative (air) atmospheres. Physical and chemical mechanisms are identified and related to the unique nanostructure and its low thermal conductivity, high gas barrier properties and CNF/ MTM interactions for char formation.

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