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  • 151.
    Bergenstrahle, Malin
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology.
    Berglund, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Mazeau, Karim
    CNRS, Ctr Rech Macromol Vegetales, F-38041 Grenoble, France..
    CARB 18-Thermal response in crystalline cellulose: A molecular dynamics study2008In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 235Article in journal (Other academic)
  • 152.
    Berglund, Jennie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology. Wallenberg Wood Science Center.
    Wood Hemicelluloses - Fundamental Insights on Biological and Technical Properties2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Hemicelluloses are a group of heterogeneous polysaccharides representing around 30 % of wood where the dominating types are xylans, glucomannans and xyloglucans. Hemicelluloses complex molecular structure makes it difficult to understand the relationship between structure and properties entirely, and their biological role is not yet fully verified. Additionally, hemicelluloses are sensitive to chemical processing and are not utilized to their full potentials for production of value-added products such as materials, additives to food and pharmaceutical products, etc. Increased knowledge regarding their functions is important for the development of both processes and products. The aim with this work has therefore been to increase the fundamental understanding about how the structure and properties of wood hemicelluloses are correlated, and properties such as flexibility, interaction with cellulose, solubility, resistance to chemical-, thermal-, and enzymatic degradation have been explored.

    Molecular dynamics (MD) simulations were used to, in detail, study the structures found in wood hemicelluloses. The flexibility was evaluated by comparing the impact of backbone sugars on the conformational space and also the impact of side groups was considered. Based on the conformational space of backbone glycosidic linkages the flexibility order of hemicelluloses in an aqueous environment was determined to be: xylan > glucomannan > xyloglucan. Additionally, the impact of xylan structure on cellulose interaction was evaluated by MD methods.

    Hemicelluloses were extracted from birch and spruce, and were used to fabricate different composite hydrogels with bacterial cellulose. These materials were studied with regards to mechanical properties, and it was shown that galactoglucomannans mainly contributed to an increased modulus in compression, whereas the most significant effect from xylan was increased strain under uniaxial tensile testing. Besides, other polysaccharides of similar structure as galactoglucomannans were modified and used as pure, well defined, models. Acetyl groups are naturally occurring decorations of wood hemicelluloses and can also be chemically introduced. Here, mannans with different degrees of acetylation were prepared and the influence of structure on solubility in water and the organic solvent DMSO were evaluated. Furthermore, the structure and water solubility influenced the interaction with cellulose. Acetylation also showed to increase the thermal and biological stability of mannans.

    With chemical pulping processes in mind, the degradability of spruce galactoglucomannans in alkaline solution were studied with regards to the structure, and the content of more or less stable structural regions were proposed.

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  • 153.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Azhar, Shoaib
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Wohlert, Jakob
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    The structure of galactoglucomannan impacts the degradation under alkaline conditions2018In: Cellulose, ISSN 0969-0239, E-ISSN 1572-882XArticle in journal (Refereed)
    Abstract [en]

    Galactoglucomannan (GGM) from sprucewas studied with respect to the degradation behavior inalkaline solution. Three reference systems includinggalactomannan from locust bean gum, glucomannanfrom konjac and the linear water-soluble carboxymethylcellulose were studied with focus onmolecular weight, sugar composition, degradationproducts, as well as formed oligomers, to identifyrelative structural changes in GGM. Initially allmannan polysaccharides showed a fast decrease inthe molecular weight, which became stable in the laterstage. The degradation of the mannan polysaccharidescould be described by a function corresponding to thesum of two first order reactions; one slow that wasascribed to peeling, and one fast that was connectedwith hydrolysis. The galactose side group wasstable under conditions used in this study (150 min,90 C, 0.5 M NaOH). This could suggest that, apartfrom the covalent connection to C6 in mannose, thegalactose substitutions also interact non-covalentlywith the backbone to stabilize the structure againstdegradation. Additionally, the combination of differentbackbone sugars seems to affect the stability of thepolysaccharides. For carboxymethyl cellulose thedegradation was linear over time which furthersuggests that the structure and sugar composition playan important role for the alkaline degradation. Moleculardynamics simulations gave details about theconformational behavior of GGM oligomers in watersolution, as well as interaction between the oligomersand hydroxide ions.

  • 154.
    Berglund, Jennie
    et al.
    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.
    Berqenstråhle, Malin
    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.
    Vilaplana, Francisco
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Biotechnology (BIO), Centres, Albanova VinnExcellence Center for Protein Technology, ProNova. KTH, School of Biotechnology (BIO), Glycoscience.
    d'Ortoli, Thibault Angles
    Stockholm Univ, Dept Organ Chem, Stockholm, Sweden..
    Widmalm, Goran
    Stockholm Univ, Dept Organ Chem, Stockholm, Sweden..
    Lawoko, Martin
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, School of Chemical Science and Engineering (CHE), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, Mikael
    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.
    Wohlert, Jakob
    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.
    How the flexibility properties of hemicelluloses are affected by the glycosidic bonds between different backbone sugars - A molecular dynamics study2016In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 251Article in journal (Other academic)
  • 155.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Chen, Pan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Wohlert, Jakob
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Computer modeling of the structure and dynamics of hemicelluloses2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 156.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Farahani, Saina Kishani
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    de Carvalho, Danila Morais
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Wohlert, Jakob
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience.
    Acetylation and Sugar Composition Influence the (In)Solubility of Plant beta-Mannans and Their Interaction with Cellulose Surfaces2020In: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 8, no 27, p. 10027-10040Article in journal (Refereed)
    Abstract [en]

    Plant beta-mannans are complex heteropolysaccharides that represent an abundant resource from lignocellulosic biomass. The influence of the molecular motifs of plant mannans on the backbone flexibility, solubility, and the interaction with cellulose was investigated by computational and experimental approaches. The regioselectivity of the acetyl substitutions at C2 and C3 distinctively influenced backbone flexibility in aqueous media, as revealed by molecular dynamic simulations. The molecular weight and degree of acetylation were tailored for two model seed mannans (galactomannan and glucomannan) and compared to spruce acetylated galactoglucomannan. The thermal stability was enhanced with increasing acetyl substitutions, independently of the type of mannan. Dynamic light scattering and atomic force microscopy revealed that the occurrence of galactosylation and a low degree of acetylation (similar to that of native acetylated galactoglucomannans) enhanced solubility/dispersibility of mannans, whereas the solubility/dispersibility decreased for higher degrees of acetylation. Mannan solubility influenced their interactions with cellulose at water-cellulose interfaces in terms of adsorbed mass and viscoelastic properties of the adsorbed mannan layers. Our results reveal that modulating the molecular motifs of plant beta-mannans influences their macromolecular conformation and physicochemical properties, with fundamental implications for their role in the plant cell wall and the design of wood-based materials.

  • 157.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Farahani, Saina Kishani
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    de Carvalho, Danila Morais
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Wohlert, Jakob
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience. AlbaNova University Centre.
    The influence of acetylation and sugar composition on the (in)solubility of mannans, their interaction with cellulose surfaces and thermal propertiesManuscript (preprint) (Other academic)
  • 158.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Kishani, Saina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    de Carvalho, Danila Morais
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lawoko, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Wohlert, Jakob
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Wågberg, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience.
    The influence of acetylation and sugar composition on the (in)solubility of mannans, their interaction with cellulose surfaces and thermal properties.Manuscript (preprint) (Other academic)
  • 159.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Mikkelsen, Deidre
    Flanagan, Bernadine M.
    Dhital, Sushil
    Gaunitz, Stefan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Yakubov, Gleb E.
    Gidley, Michael J.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Wood hemicelluloses exert distinct biomechanical contributions to cellulose fibrillar networks2020In: Nature Communications, E-ISSN 2041-1723, Vol. 11, no 1, article id 4692Article in journal (Refereed)
    Abstract [en]

    Hemicelluloses, a family of heterogeneous polysaccharides with complex molecular structures, constitute a fundamental component of lignocellulosic biomass. However, the contribution of each hemicellulose type to the mechanical properties of secondary plant cell walls remains elusive. Here we homogeneously incorporate different combinations of extracted and purified hemicelluloses (xylans and glucomannans) from softwood and hardwood species into self-assembled networks during cellulose biosynthesis in a bacterial model, without altering the morphology and the crystallinity of the cellulose bundles. These composite hydrogels can be therefore envisioned as models of secondary plant cell walls prior to lignification. The incorporated hemicelluloses exhibit both a rigid phase having close interactions with cellulose, together with a flexible phase contributing to the multiscale architecture of the bacterial cellulose hydrogels. The wood hemicelluloses exhibit distinct biomechanical contributions, with glucomannans increasing the elastic modulus in compression, and xylans contributing to a dramatic increase of the elongation at break under tension. These diverging effects cannot be explained solely from the nature of their direct interactions with cellulose, but can be related to the distinct molecular structure of wood xylans and mannans, the multiphase architecture of the hydrogels and the aggregative effects amongst hemicellulose-coated fibrils. Our study contributes to understanding the specific roles of wood xylans and glucomannans in the biomechanical integrity of secondary cell walls in tension and compression and has significance for the development of lignocellulosic materials with controlled assembly and tailored mechanical properties.

  • 160.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Mikkelsen, Deirdre
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Flanagan, Bernadine
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Dhital, Sushil
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Yakubov, Gleb
    Univ Queensland, Sch Chem Engn, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Gidley, Michael
    Univ Queensland, Queensland Alliance Agr & Food Innovat, Ctr Nutr & Food Sci, ARC Ctr Excellence Plant Cell Walls, Brisbane, Qld, Australia..
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Glycoscience. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Hydrogels of bacterial cellulose and wood hemicelluloses as a model of plant secondary cell walls2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 161.
    Berglund, Jennie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Mikkelsen, Deirdre
    University of Queensland, Australia.
    Flanagan, Bernadine M.
    University of Queensland, Australia.
    Dhital, Sushil
    University of Queensland, Australia.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Yakubov, Gleb E.
    University of Queensland, Australia.
    Gidley, Michael J.
    University of Queensland, Australia.
    Vilaplana, Francisco
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Wood Hemicelluloses Exert Distinct Biomechanical Contributions in Bacterial Cellulose HydrogelsManuscript (preprint) (Other academic)
  • 162.
    Berglund, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Wood biocomposites and structural fibre materials2021In: Mechanics of Paper Products, Walter de Gruyter GmbH , 2021, p. 281-309Chapter in book (Other academic)
  • 163.
    Berglund, Lars A.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Peijs, Ton
    Cellulose Biocomposites: From Bulk Moldings to Nanostructured Systems2010In: MRS bulletin, ISSN 0883-7694, E-ISSN 1938-1425, Vol. 35, no 3, p. 201-207Article in journal (Refereed)
    Abstract [en]

    Cellulose biocomposites are widely used in industry as a low-cost engineering material with plant fiber reinforcement. However, chemical and microstructural heterogeneity causes low strength, low strain-to-failure, high moisture sensitivity, and odor and discoloration problems. Efforts toward improved performance through fiber orientation control, increased fiber lengths, and biopolymer use are reviewed. Interfacial strength control and moisture sensitivity are remaining challenges. As an attractive alternative reinforcement, high-quality cellulose nanofibers obtained by wood pulp fiber disintegration can be prepared at low cost. These nanofibers have high length/diameter ratios, diameters in the 5-15 nm range, and intrinsically superior physical properties. Wood cellulose nanofibers are interesting as an alternative reinforcement to more expensive nanoparticles, such as carbon nanotubes. Nanopaper and polymer matrix nanocomposites based on cellulose nanofiber networks show high strength, high work-of-fracture, low moisture adsorption, low thermal expansion, high thermal stability, high thermal conductivity, exceptional barrier properties, and high optical transparency. The favorable mechanical performance of bioinspired foams and low-density aerogels is reviewed. Future applications of cellulose biocomposites will be extended from the high-volume/low-cost end toward high-tech applications, where cellulose properties are fully exploited in nanostructured materials.

  • 164.
    Berglund, Lars
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Ansari, Farhan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Cellulose Nanocomposites With Ductile Mechanical Behavior2015In: 20Th International Conference On Composite Materials / [ed] Thomsen, OT Berggreen, C Sorensen, BF, AALBORG UNIV PRESS , 2015Conference paper (Refereed)
    Abstract [en]

    The limited ductility of plant fiber biocomposites is typically caused by interfacial debonding mechanisms at low strain. This leads to damage development and premature failure. The present paper discusses recent results on cellulose nanocomposites with thermoset and thermoplastic matrices, where substantial ductility is observed. The data are presented and reasons for the observed ductility are discussed.

  • 165.
    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.

  • 166.
    Berglund, Lars
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Li, Yuanyuan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Fu, Qiliang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Popov, Sergei
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Sychugov, Ilya
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Yang, Min
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Modification of transparent wood for photonics functions2018In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal (Other academic)
  • 167.
    Berglund, Lars
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Yang, Xuan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Design of biodegradable cellulosic nanomaterials combining mechanical strength and optical transmittance2018In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 256Article in journal (Other academic)
  • 168.
    Berglund, Lars
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Yang, Xuan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Berthold, Fredrik
    RISE Bioecon, Stockholm, Sweden..
    Holocellulose fibers: combining mechanical performance and optical transmittance2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 169.
    Betker, Marie
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Harder, Constantin
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Erbes, Elisabeth
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Institute for X-ray Physics, Goettingen University, Friedrich Hund Platz 1, 37077 Goettingen, Germany, Friedrich Hund Platz 1.
    Heger, Julian Eliah
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Alexakis, Alexandros Efraim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Sochor, Benedikt
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Chen, Qing
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Schwartzkopf, Matthias
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Körstgens, Volker
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1.
    Müller-Buschbaum, Peter
    Chair for Functional Materials, TUM School of Natural Sciences, Technical University of Munich, James-Franck-Straße 1, 85748 Garching, Germany, James-Franck-Straße 1; Heinz Maier-Leibnitz Zentrum (MLZ), Technical University of Munich, Lichtenbergstr. 1, 85748 Garching, Germany, Lichtenbergstr. 1.
    Schneider, Konrad
    Abteilung Werkstofftechnik, Leibniz-Institut für Polymerforschung Dresden e.V., 01069 Dresden, Germany.
    Techert, Simone Agnes
    Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85; Institute for X-ray Physics, Goettingen University, Friedrich Hund Platz 1, 37077 Goettingen, Germany, Friedrich Hund Platz 1.
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen-Synchrotron DESY, Notkestr. 85, 22607 Hamburg, Germany, Notkestr. 85.
    Sprayed Hybrid Cellulose Nanofibril-Silver Nanowire Transparent Electrodes for Organic Electronic Applications2023In: ACS Applied Nano Materials, E-ISSN 2574-0970, Vol. 6, no 14, p. 13677-13688Article in journal (Refereed)
    Abstract [en]

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

  • 170.
    Bettelli, Mercedes A.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Hu, Qisong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Capezza, Antonio Jose
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Johansson, Eva
    Department of Plant Breeding, The Swedish University of Agricultural Sciences, Box 190, SE-234 22, Lomma, Sweden.
    Olsson, Richard
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Hedenqvist, Mikael S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Effects of multi-functional additives during foam extrusion of wheat gluten materials2024In: Communications Chemistry, E-ISSN 2399-3669, Vol. 7, no 1, article id 75Article in journal (Refereed)
    Abstract [en]

    To broaden the range in structures and properties, and therefore the applicability of sustainable foams based on wheat gluten expanded with ammonium-bicarbonate, we show here how three naturally ocurring multifunctional additives affect their properties. Citric acid yields foams with the lowest density (porosity of ~50%) with mainly closed cells. Gallic acid acts as a radical scavenger, yielding the least crosslinked/ aggregated foam. The use of a low amount of this acid yields foams with the highest uptake of the body-fluid model substance (saline, ~130% after 24 hours). However, foams with genipin show a large and rapid capillary uptake (50% in one second), due to their high content of open cells. The most dense and stiff foam is obtained with one weight percent genipin, which is also the most crosslinked. Overall, the foams show a high energy loss-rate under cyclic compression (84-92% at 50% strain), indicating promising cushioning behaviour. They also show a low compression set, indicating promising sealability. Overall, the work here provides a step towards using protein biofoams as a sustainable alternative to fossil-based plastic/rubber foams in applications where absorbent and/or mechanical properties play a key role.

  • 171.
    Bettelli, Mercedes
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Capezza, Antonio Jose
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Nilsson, F.
    Johansson, E.
    Olsson, Richard
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Hedenqvist, Mikael S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Sustainable Wheat Protein Biofoams: Dry Upscalable Extrusion at Low Temperature2022In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 23, no 12, p. 5116-5126Article in journal (Refereed)
    Abstract [en]

    Glycerol-plasticized wheat gluten was explored for producing soft high-density biofoams using dry upscalable extrusion (avoiding purposely added water). The largest pore size was obtained when using the food grade ammonium bicarbonate (ABC) as blowing agent, also resulting in the highest saline liquid uptake. Foams were, however, also obtained without adding a blowing agent, possibly due to a rapid moisture uptake by the dried protein powder when fed to the extruder. ABC's low decomposition temperature enabled extrusion of the material at a temperature as low as 70 °C, well below the protein aggregation temperature. Sodium bicarbonate (SBC), the most common food-grade blowing agent, did not yield the same high foam qualities. SBC's alkalinity, and the need to use a higher processing temperature (120 °C), resulted in high protein cross-linking and aggregation. The results show the potential of an energy-efficient and industrially upscalable low-temperature foam extrusion process for competitive production of sustainable biofoams using inexpensive and readily available protein obtained from industrial biomass (wheat gluten). 

  • 172.
    Bevin, Anna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Quantitative and qualitative analysis of dyes in pulp from recycled textiles2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    To decrease the environmental footprint, the textile industry needs to become more circular. One company that is trying to close the textile lifecycle loop is the Swedish company Renewcell. In the Renewcell process, discarded clothes and other textile waste are turned into a dissolving pulp that can be used for production of new textiles. For this to work, it is important to generate a non-colored dissolved pulp. Therefore, it is of great interest to be able to optimize the bleaching process and evaluate different starting materials. Today, there are different methods that have been used for quantification of specific dyes and for identification of raw materials in textiles. However, there is no complete method that can be used for all types of dyes and raw materials. This master thesis will therefore investigate the bleaching step and the raw materials used in Renewcell’s recycling process. The aim with this project is to develop a method, to be able to analyse the presence of dyes qualitatively and quantitatively in the dissolved pulp from the recycled cotton-based textiles. To do so, different chemical analysing methods were used. These include kappa number measurements, UV-VIS and FTIR. Nine different types of jeans, one yarn, three raw materials (cotton, PET and elastane), and two pure dyes (indigo and black sulfur dye) were selected for this project. The result from the kappa number measurements shows that only the blue jeans, blue yarn and black jeans could be bleached and measured by using the original kappa number method at 25 degrees C. But when the same procedure was done manually and the temperature was increased to 70 degrees C, almost all materials could be bleached and measured. Therefore, the conclusion is that this method can be a successful quantification method. However, the temperature correction equation needs to be developed further to be able to quantify the exact amount of dyes. The kappa number was also compared with the absorbance factor, i.e. the k-value from the UV-VIS results. A correlation could be seen for the blue jeans, blue yarn, and black jeans. So, the UV-VIS method could also be a possible method for quantification of dyes in textiles. For the qualitative analyses, FTIR was used. The results showed that the raw materials could be identified by comparing the resulting FTIR spectra with a reference spectrum. For the jeans and yarn materials, indigo dye was identified for the blue jeans, blue yarn, and black jeans. However, for the other materials, the amount of dyes was too low to be able to draw conclusions about the chemical structure. With further development, these methods could be used as successful qualitative and quantitative methods for analysing dyes in textiles. This would generate positive consequences in several ways. The usage of bleaching chemicals could be optimized, and the quality of the final textile material could be improved. This would benefit both the manufacturer of these recycled textiles (economically) and the consumer who will buy the final product (quality). Indirectly, this would help to decrease the environmental footprint from the textile industry. 

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  • 173.
    Bharj, Gurpreet Kaur
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sustainable resins for large rotating machines2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The electrical insulation system for large rotating machines consists of a composite material of mica tape and a thermosetting resin. The resin helps in mechanically stabilizing the winding structure in the stator as well as replaces air inclusions in the insulation system to suppress the formation of discharges. Vacuum pressure impregnation (VPI) is the preferred technique to impregnate this mica tape with the thermosetting resin. The resin used in VPI process is composed of several key components, including the thermoset polymer, a hardener that participates in crosslinking, reactive diluents for improved processability and and additional additives like catalysts and stabilizers. Different chemistries have been used over the years for the VPI process. However, there are significant concerns regarding the environmental and occupational health and safety of some of these components. 

    The increasing awareness of the harmful effects of various chemicals has driven efforts to develop resins with reduced volatile organic compounds which can be detrimental to both the environment as well as those who are handling the resin in large quantities. Furthermore, stringent EU regulations have classified some hardeners and reactive diluents as substances of very high concern which has resulted in pressing need to find alternatives for these compounds. 

    This thesis, thus, consists of a literature study which has been performed taking the desired properties for VPI resins into consideration to evaluate potential candidates as alternatives for hardeners, and reactive diluents. Four different chemistries of impregnation have been taken into consideration as alternatives. Different curing kinetics parameters have been measured by different characterization techniques such as real time Fourier transform infrared spectroscopy, rheology, and differential scanning calorimetry. As the thermal, electric, and mechanical factors are necessary to ensure long term lifespan of industrial machines, different properties have been studied by performing dynamic mechanical analysis, tensile and flexural testing as well as dielectric spectroscopy by curing the resins under appropriate time and temperature conditions. All the four resins showed varied curing kinetics parameters and properties which have been correlated to the chemistry involved in the resin as well as evaluated in comparison to each other.

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  • 174.
    Bharj, Gurpreet Kaur
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sustainable resins for large rotating machines2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The electrical insulation system for large rotating machines consists of a composite material of mica tape and a thermosetting resin. The resin helps in mechanically stabilizing the winding structure in the stator as well as replaces air inclusions in the insulation system to suppress the formation of discharges. Vacuum pressure impregnation (VPI) is the preferred technique to impregnate this mica tape with the thermosetting resin. The resin used in VPI process is composed of several key components, including the thermoset polymer, a hardener that participates in crosslinking, reactive diluents for improved processability and and additional additives like catalysts and stabilizers. Different chemistries have been used over the years for the VPI process. However, there are significant concerns regarding the environmental and occupational health and safety of some of these components. 

    The increasing awareness of the harmful effects of various chemicals has driven efforts to develop resins with reduced volatile organic compounds which can be detrimental to both the environment as well as those who are handling the resin in large quantities. Furthermore, stringent EU regulations have classified some hardeners and reactive diluents as substances of very high concern which has resulted in pressing need to find alternatives for these compounds. 

    This thesis, thus, consists of a literature study which has been performed taking the desired properties for VPI resins into consideration to evaluate potential candidates as alternatives for hardeners, and reactive diluents. Four different chemistries of impregnation have been taken into consideration as alternatives. Different curing kinetics parameters have been measured by different characterization techniques such as real time Fourier transform infrared spectroscopy, rheology, and differential scanning calorimetry. As the thermal, electric, and mechanical factors are necessary to ensure long term lifespan of industrial machines, different properties have been studied by performing dynamic mechanical analysis, tensile and flexural testing as well as dielectric spectroscopy by curing the resins under appropriate time and temperature conditions. All the four resins showed varied curing kinetics parameters and properties which have been correlated to the chemistry involved in the resin as well as evaluated in comparison to each other.

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  • 175.
    Bi, Ran
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Huang, Shan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Henriksson, Gunnar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Wood Chemistry and Pulp Technology.
    Isolation Of Exceedingly Low Oxygen Consuming Fungal Strains Able To Utilize Lignin As Carbon Source2016In: Cellulose Chemistry and Technology, ISSN 0576-9787, Vol. 50, no 7-8, p. 811-817Article in journal (Refereed)
    Abstract [en]

    Lignin biodegradation is normally related to aerobic microorganisms, and it is often claimed that microbes do not metabolize lignin as a carbon source. In this work, several fungal strains were isolated from the sediment of a small stream located in a forest and tested on agar plates with lignin as the only carbon source. All identified strains were Ascomycetes, Penicillium spinulosum, Pseudeurotium bakeri and Galactomyces geotrichum. When cultivated in shaking flasks with lignosulphonate as a carbon source, the lignin was consumed, and cell free culture filtrates appeared to depolymerize lignosulphonate to some extent. It is suggested that the strains detected are part of a symbiotic community and live in a microbiological niche in which they are able to utilize lignin residues left from brown rot and humus having extremely low oxygen content.

  • 176. 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, 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.

  • 177.
    Birdsong, Björn K.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Hoogendoorn, Billy W.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials. Department of Fibre and Polymer Technology, KTH Royal Institute of Technology, Teknikringen 58 11428 Stockholm Sweden.
    Nilsson, Fritjof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials. Mid Sweden University Sundsvall 85170 Sweden.
    Andersson, Richard L.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Capezza, Antonio Jose
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Hedenqvist, Mikael S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Farris, Stefano
    DeFENS - Department of Food, Environmental and Nutritional Sciences Food Packaging Laboratory, Via Celoria 2, Milan, 20133, Italy.
    Guerrero, Antonio
    Department of Chemical Engineering, Escuela Politécnica Superior, Universidad de Sevilla, Sevilla, 41011, Spain.
    Olsson, Richard
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Large-scale synthesis of 2D-silica (SiOx) nanosheets using graphene oxide (GO) as a template material2023In: Nanoscale, ISSN 2040-3364, E-ISSN 2040-3372, Vol. 15, no 31, p. 13037-13048Article in journal (Refereed)
    Abstract [en]

    Graphene oxide (GO) was used in this study as a template to successfully synthesize silicon oxide (SiOx) based 2D-nanomaterials, adapting the same morphological features as the GO sheets. By performing a controlled condensation reaction using low concentrations of GO (<0.5 wt%), the study shows how to obtain 2D-nanoflakes, consisting of GO-flakes coated with a silica precursor that were ca. 500 nm in lateral diameter and ca. 1.5 nm in thickness. XPS revealed that the silanes had linked covalently with the GO sheets at the expense of the oxygen groups present on the GO surface. The GO template was shown to be fully removable through thermal treatment without affecting the nanoflake morphology of the pure SiOx-material, providing a methodology for large-scale preparation of SiOx-based 2D nanosheets with nearly identical dimensions as the GO template. The formation of SiOx sheets using a GO template was investigated for two different silane precursors, (3-aminopropyl) triethoxysilane (APTES) and tetraethyl orthosilicate (TEOS), showing that both precursors were capable of accurately templating the graphene oxide template. Molecular modeling revealed that the choice of silane affected the number of layers coated on the GO sheets. Furthermore, rheological measurements showed that the relative viscosity was significantly affected by the specific surface area of the synthesized particles. The protocol used showed the ability to synthesize these types of nanoparticles using a common aqueous alcohol solvent, and yield larger amounts (∼1 g) of SiOx-sheets than what has been previously reported.

  • 178.
    Biscari, Giuseppina
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Fan, Yanmiao
    Univ Palermo, Via Archirafi 32, I-90123 Palermo, Italy..
    Namata, Faridah
    Univ Palermo, Via Archirafi 32, I-90123 Palermo, Italy..
    Fiorica, Calogero
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Malkoch, Michael
    Univ Palermo, Via Archirafi 32, I-90123 Palermo, Italy..
    Palumbo, Fabio Salvatore
    Univ Palermo, Via Archirafi 32, I-90123 Palermo, Italy..
    Pitarresi, Giovanna
    Univ Palermo, Via Archirafi 32, I-90123 Palermo, Italy..
    Antibacterial Broad-Spectrum Dendritic/Gellan Gum Hybrid Hydrogels with Rapid Shape-Forming and Self-Healing for Wound Healing Application2023In: Macromolecular Bioscience, ISSN 1616-5187, E-ISSN 1616-5195, article id 202300224Article in journal (Refereed)
    Abstract [en]

    Treating wound infections is a difficult task ever since pathogenic bacteria started to develop resistance to common antibiotics. The present study develops hybrid hydrogels based on the formation of a polyelectrolyte complex between the anionic charges of dopamine-functionalized Gellan Gum (GG-DA) and the cationic moieties of the TMP-G2-alanine dendrimer. The hydrogels thus obtained can be doubly crosslinked with CaCl2, obtaining solid hydrogels. Or, by oxidizing dopamine to GG-DA, possibly causing further interactions such as Schiff Base and Michael addition to take place, hydrogels called injectables can be obtained. The latter have shear-thinning and self-healing properties (efficiency up to 100%). Human dermal fibroblasts (HDF), human epidermal keratinocytes (HaCaT), and mouse monocyte cells (RAW 264.7), after incubation with hydrogels, in most cases show cell viability up to 100%. Hydrogels exhibit adhesive behavior on various substrates, including porcine skin. At the same time, the dendrimer serves to crosslink the hydrogels and endows them with excellent broad-spectrum microbial eradication activity within four hours, evaluated using Staphylococcus aureus 2569 and Escherichia coli 178. Using the same GG-DA/TMP-G2-alanine ratios hybrid hydrogels with tunable properties and potential for wound dressing applications can be produced.

  • 179.
    Biscari, Giuseppina
    et al.
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Malkoch, Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Fiorica, Calogero
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Fan, Yanmiao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Palumbo, Fabio Salvatore
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Indelicato, Serena
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Bongiorno, David
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Pitarresi, Giovanna
    University of Palermo, Via Archirafi 32, Palermo, 90123, Italy.
    Gellan gum-dopamine mediated in situ synthesis of silver nanoparticles and development of nano/micro-composite injectable hydrogel with antimicrobial activity2024In: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 258, article id 128766Article in journal (Refereed)
    Abstract [en]

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

  • 180.
    Bishnoi, Shahana
    et al.
    Tech Univ Denmark DTU 202, DTU Food, DK-2800 Lyngby, Denmark..
    Trifol, Jon
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Aalto Univ, Sch Chem Engn, Dept Chem & Met Engn, POB 16300, FIN-00076 Espoo, Finland..
    Moriana Torro, Rosana
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Mendes, Ana C.
    Tech Univ Denmark DTU 202, DTU Food, DK-2800 Lyngby, Denmark..
    Adjustable polysaccharides-proteins films made of aqueous wheat proteins and alginate solutions2022In: Food Chemistry, ISSN 0308-8146, E-ISSN 1873-7072, Vol. 391, p. 133196-, article id 133196Article in journal (Refereed)
    Abstract [en]

    Large amount of wheat proteins by-products are produced during wheat starch manufacture. This work aimed to develop edible films of cast aqueous wheat proteins (WP) and alginate (Al) solutions. The investigation of the microstructure of Al/WP films revealed a more compacted cross-section and homogeneous surface, comparatively to Al films. Those properties could be modified with the increase of WP concentration from 4 to 8 % w/v, as result of electrostatic interactions between WP and Al. Furthermore, the incorporation of WP provided UltraViolet-blocking behaviour (4-fold decrease in the Ultra-Violet-B region). Additionally, the incorporation of WP in the films reduced the water solubility of the Al films. It was also found that by incorporating different amounts of WP the mechanical and Water Vapor Transmission rate (WVTR) properties could also be modified, so the film composition could be adjusted to suit different types of foods and applications (e.g. coatings and packaging).

  • 181.
    Biundo, Antonino
    et al.
    Univ Nat Resources & Life Sci, Vienna, Austria..
    Ribitsch, Doris
    Austrian Ctr Ind Biotechnol, Graz, Austria..
    Syrén, Per-Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. Vienna, Austria..
    Guebitz, Georg M.
    Univ Nat Resources & Life Sci, Vienna, Austria..
    Increasing amide acceptance on a polyester-hydrolyzing enzyme2016In: New Biotechnology, ISSN 1871-6784, E-ISSN 1876-4347, Vol. 33, p. S105-S105Article in journal (Other academic)
  • 182.
    Biundo, Antonino
    et al.
    University of Bari, Department of Biosciences, Biotechnology and Biopharmaceutics, via Orabona, 4, Bari, 70125, Italy, via Orabona, 4; REWOW srl, Via Ciasca 9, Bari, 70124, Italy, Via Ciasca 9.
    Saénz Méndez, Patricia
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Karlstads Universitet, Faculty of Health, Science and Technology, Universitetsgatan 2, 65188 Karlstad, Sweden.
    Görbe, Tamas
    Menten AI, 2225 E Bayshore Road, Suite 200, Palo Alto, CA, 94303, USA.
    Enzyme Modification2021In: Biocatalysis for Practitioners: Techniques, Reactions and Applications, Wiley , 2021, p. 33-62Chapter in book (Other academic)
    Abstract [en]

    The chapter on protein engineering has introduced and discussed an overview of the available methods for the modification of enzymes. Starting with the classical directed evolution (DE) technique, which has been applied extensively throughout several different biocatalytic processes, the reader moves toward the semi-rational, rational, and de novo design of enzymes. Meanwhile, DE is clearly the current industry-leading technology; depending on the understanding of the particular enzymatic system, and on the available structural information, other techniques such as rational design are also becoming fast and efficient solutions for the development of new catalysts. This success would not be possible without the constant improvements of the computational techniques and the newly developed modeling systems for enzyme engineering.

  • 183.
    Biundo, Antonino
    et al.
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy.;REWOW Srl, Via G Matarrese 10, I-70124 Bari, Italy..
    Stamm, Arne
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Gorgoglione, Ruggiero
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy..
    Syrén, Per-Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Curia, Silvio
    Rowan Univ, Dept Chem Engn, 201 Mullica Hill Rd, Glassboro, NJ 08028 USA..
    Hauer, Bernhard
    Univ Stuttgart, Dept Tech Biochem, Allmandring 31, D-70569 Stuttgart, Germany..
    Capriati, Vito
    Univ Bari Aldo Moro, Dept Pharm Drug Sci, Via E Orabona 4, I-70125 Bari, Italy..
    Vitale, Paola
    Univ Bari Aldo Moro, Dept Pharm Drug Sci, Via E Orabona 4, I-70125 Bari, Italy..
    Perna, Filippo
    Univ Bari Aldo Moro, Dept Pharm Drug Sci, Via E Orabona 4, I-70125 Bari, Italy..
    Agrimi, Gennaro
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy..
    Pisano, Isabella
    Univ Bari Aldo Moro, Dept Biosci Biotechnol & Environm, Via E Orabona 4, I-70125 Bari, Italy..
    Regio- and stereoselective biocatalytic hydration of fatty acids from waste cooking oils en route to hydroxy fatty acids and bio-based polyesters2023In: Enzyme and microbial technology, ISSN 0141-0229, E-ISSN 1879-0909, Vol. 163, article id 110164Article in journal (Refereed)
    Abstract [en]

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

  • 184.
    Biundo, Antonino
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science. KTH, Centres, Science for Life Laboratory, SciLifeLab. ACIB, Konrad Lorenz Str 20, A-3430 Tulln An Der Donau, Austria.
    Subagia, Raditya
    Univ Nat Resources & Life Sci BOKU, Inst Environm Biotechnol, Konrad Lorenz Str 20, A-3430 Tulln An Der Donau, Austria..
    Maurer, Michael
    Univ Appl Sci, Dept Bioengn, Mauerbachstr 43, A-1140 Vienna, Austria..
    Ribitsch, Doris
    ACIB, Konrad Lorenz Str 20, A-3430 Tulln An Der Donau, Austria.;Univ Nat Resources & Life Sci BOKU, Inst Environm Biotechnol, Konrad Lorenz Str 20, A-3430 Tulln An Der Donau, Austria..
    Syrén, Per-Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Guebitz, Georg M.
    ACIB, Konrad Lorenz Str 20, A-3430 Tulln An Der Donau, Austria.;Univ Nat Resources & Life Sci BOKU, Inst Environm Biotechnol, Konrad Lorenz Str 20, A-3430 Tulln An Der Donau, Austria..
    Switched reaction specificity in polyesterases towards amide bond hydrolysis by enzyme engineering2019In: RSC Advances, E-ISSN 2046-2069, Vol. 9, no 62, p. 36217-36226Article in journal (Refereed)
    Abstract [en]

    The recalcitrance of plastics like nylon and other polyamides contributes to environmental problems (e.g. microplastics in oceans) and restricts possibilities for recycling. The fact that hitherto discovered amidases (EC 3.5.1. and 3.5.2.) only show no, or low, activity on polyamides currently obstructs biotechnological-assisted depolymerization of man-made materials. In this work, we capitalized on enzyme engineering to enhance the promiscuous amidase activity of polyesterases. Through enzyme design we created a reallocated water network adapted for hydrogen bond formation to synthetic amide backbones for enhanced transition state stabilization in the polyester-hydrolyzing biocatalysts Humicola insolens cutinase and Thermobifida cellulosilytica cutinase 1. This novel concept enabled increased catalytic efficiency towards amide-containing soluble substrates. The afforded enhanced hydrolysis of the amide bond-containing insoluble substrate 3PA 6,6 by designed variants was aligned with improved transition state stabilization identified by molecular dynamics (MD) simulations. Furthermore, the presence of a favorable water-molecule network that interacted with synthetic amides in the variants resulted in a reduced activity on polyethylene terephthalate (PET). Our data demonstrate the potential of using enzyme engineering to improve the amidase activity for polyesterases to act on synthetic amide-containing polymers.

  • 185.
    Bjerkensjö, Max
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    The thermal properties of biobased waxes in food industry2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    One ofthe ways many companies in have tried to mitigate environmental impacts, contribution to climate change and carbon footprint is to phase out products that are derived from fossil fuel. Procudan is a danish packaging company that have decided to phase out one of their petroleum products, namely mineral oil waxes used for their food packaging. As an substitute for their current product Procudan has instead made a biobased wax with beeswax as its main component. Before utilising this wax however their thermal properties need to be analysed. Mettler-Toledo was tasked to perform the analysis of these new biobased wax formulations, their raw material components, additives as well as the currently used waxes and raw materials. The properties that were determined was when the waxes melted and crystallised, the enthalpies of each reactions, and the degradation effects of oxygen and nitrogen respectively. These analysis were done using DSC and OJT, TGA and GC-MS. After these results were evaluated they were compared with that of the mineral oil waxes. What resulted from the DSC analysis was to show that the biobased waxes contained a lot of thermal history and required somewhat more energy to melt and crystallise, which potentially will increase the energy costs for cus(omers. At the same time the TGA and OIT showed that there was little concern for early degradation oj the biobased waxes by Oxygen and Nitrogen gases. Complete degradation of any of the waxes did not occur until the waxes reached temperatures far higher than any production parameters would have. As the GC-MS showed, when this eventual degradation does occur in oxygen environments Acetic acid is the most common product; followed by a variety of alkenes, aldehydes and alkanes and other organic compounds. At the end of the study the biobased waxes does seem rather viable with the production parameters, with the biobased wax formulations 2 and 5 being more recommended for future applications as they had similar properties to mineral oil waxes.

  • 186.
    Bjurström, Anton
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    SCP as plastic material2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Plastics are used in a variety of applications, mostly due to their versatility and processability, making them hard to exchange for alternatives in many cases. Depending on the specific plastic material that is used, the usage also might come with certain drawbacks. The majority of plastics used today are produced from non-renewable resources, and depending on the end-of-life management, they might end up in landfill or in nature. Lately, there has also been awareness raised of issues that arises from microplastic pollution. To combat these issues, there have been several bio-sourced plastics developed and introduced to the market. Globally, the usage of bioplastics is still only accounting for under a percent of the total market. Therefore, it is concluded that there is a need for development of the sourcing and processing of raw material to produce bioplastics. This thesis proposes an alternative approach to the sourcing of material for producing bioplastics, namely the usage of single cell proteins (SCP).  Plastic films were manufactured from food-based SCP and the produced samples were tested to assess their properties. The CIELAB colour scale was used to study development of colour in the samples by scanning and digitally processing the images. This concluded a yellowish-brown colour with a darkening of sample colour with increased processing time and temperature of the compression moulding, due to Maillard reactions. SEM showed that there was not a continuous matrix forming in the samples and that there where voids and cracks both on surface and the bulk of the films. The overall mechanical properties where comparatively lower than other similar materials. With FTIR and a deconvolution of the Amide I-band (1700 to 1586 cm-1), the secondary protein structured was analysed. this showed that in the processing of the material, β-Sheets with weakly hydrogen-bonded peptide groups, are processed into both unordered protein structures and β-Sheets with strongly hydrogen-bonded peptide groups. 

  • 187.
    Björling, Alexander
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Chemical valorisation of PLA: Using the ionic liquid 2-hydroxyethyl ammonium acetate as a catalyst in a hydrolysis process2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Plastics have been around for a relatively long time now. They are a major contributor to the human living standards today. With the growing demand for plastic materials increasing every day, more plastic wastes are produced every day and needs to be dealt with. Most plastics today are produced from petroleum-based resources, but there are also bio-based alternatives, made from renewable resources, starting to get implemented into society like bio-based polyethylene and poly(lactic acid) (PLA). Plastic wastes are preferably recycled, and the most common ones are incineration for energy recovery and mechanical recycling. But a promising alternative or potential complement to the conventional recycling methods there is also chemical recycling available to treat plastic waste when mechanical recycling is not possible to use to treat the plastic waste to be put into a new circulation and rather re-build the material with better properties than mechanical recycling is able to do, but the techniques are often complex and expensive. 

    The aims of this project were to develop a hydrolysis process of PLA using 2-hydroxyethyl ammonium acetate (2-HEEA) as a catalyst for the system, focus on the circularity of the process and evaluate its thermal kinetics. The experiments were performed in reactor tubes with the materials inside placed on a heat plate under stirring at different temperatures and quantities of material inside the tubes to evaluate the optimized conditions for the system to create a circular system for the process. 

    The screening of the parameters revealed that all parameters had an effect on the system. The significant parameters from the design of experiments for the process was concluded to be the operating temperature of the process, the mass ratio between 2-HEEA and PLA, the mass ratio between water and PLA and the interaction between the operating temperature and the mass ratio between 2-HEEA and PLA. An optimization of the process was made where the parameters was set to optimum conditions where the operating temperature was 140 °C, the mass ratio between 2-HEEA and PLA was 1.5:1, and the mass ratio between water and PLA was 6:1. A circular model was implemented using those set parameters and the conversion was above 90 % until the third performed cycle when the conversion significantly decreased due to 2-HEEA losses. The kinetic model using Arrhenius equation revealed that the activation energy was 112.3 kJ/mol and that the A-value was 1.4 x 1014, which are lower values than previous studies for this process using other catalysts. 

  • 188.
    Blomfeldt, Thomas Olof John
    et al.
    KTH.
    Hedenqvist, Mikael S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Johansson, Eva
    Swedish Univ Agr Sci, Dept Crop Sci, S-23053 Alnarp, Sweden..
    CELL 176-Insulation material made from wheat gluten2008In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 235Article in journal (Other academic)
  • 189.
    Bogdan, Felix
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Evaluation of different block-copolymer coatings of iron oxide nanoparticles by flash nanoprecipitation2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Nanoparticles (NPs) offer unique possibilities for medical applications, including the controlled release of cancer drugs, the use as imaging contrast during imaging procedures or the hyperthermic treatment of cancer cells. Flash nanoprecipitation (FNP) produces NPs to combine these applications in a fast, cheap, and scalable coating process. The use of FNP with a Multi-Inlet Vortex Mixer (MIVM) is a promising method to easily coat hydrophobic oleic acid iron oxide NPs (IONPs) with various biocompatible block-copolymers. Amphiphilic block-copolymers based on hydrophilic polyethylene glycol (PEG) and hydrophobic poly(lactic acid) (PLA), poly(lactic-co-glycolic acid) (PLGA) or poly(caprolactone) (PCL) were successfully synthesized. The organic catalyst 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) was used to increase biocompatibility of the resulting polymers PEG-PLA, PEG-PL7.5KG2.5KA and PEG2K-PCL2K. The synthesis of hydroxyl terminated poly(acrylic acid) (PAA-OH) followed by the polymerization with PLGA was attempted. The amphiphilic block-copolymers were used in combination with the stabilizer polysorbate 80 (Tween80®) in FNP to form bare polymeric NPs using a MIVM as the reactor. DLS and STEM confirmed particle sizes between 50 - 100 nm. The addition of 13 ± 2 nm hydrophobic oleic acid IONPs yielded an increase in particle size as well as increase in particle stability over time. STEM images showed attachment of single IONPs to the outside of the polymeric NPs. Hydrophobic interactions between the polymer and oleic acid IONPs are possible. To achieve encapsulation of the oleic acid IONPs, adjustments to the process parameters of FNP should be considered in future research. Additional experiments are required to explore possible drug addition, release mechanisms and hyperthermia behavior of the polymer coated IONPs particles.

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  • 190.
    Bonander, Louise
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    A Novel Method for Assessing Industrial Washing Efficiency2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Pulp washing is an important step in the kraft process, as it allows for the cooking chemicals to be recovered and reused in the process, which also minimizes the environmental load to the subsequent stages. It is also important before the bleaching plant, as a low chemical oxygen demand (COD) carry-over is important to minimize the consumption of bleaching chemicals. Furthermore, washing can also remove other unwanted materials, such as metals or wood extractives. The aim of the study was to assess washing efficiency of industrial washing. The objectives were to compare industrial washing with extensive washing, to investigate the quality of wash liquors using analytical techniques and to examine existing methods for calculating washing efficiency. The experimental phase was divided into trial washing and washing series, conducted with different wash liquors, residence times and dilution factors (DF). The trial washing yielded results that allowed for the washing methodology to be improved. The results from the washing series indicated the extensive DF in general gave better results and provided a more efficient washing, and that a wash liquor of 80°C gave better results. Brightness was not affected by the dilution factor and kappa number analysis showed that there was a very slight difference compared to the original pulp. The evaluation of existing methods for calculating washing efficiency indicated that all investigated methods could give inaccurate results, but that the calculations together with other methods such as COD and conductivity should give the industry a good indication of the washing efficiency.

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  • 191.
    Boujemaoui, Assya
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Ansari, Farhan
    Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA..
    Berglund, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Nanostructural Effects in High Cellulose Content Thermoplastic Nanocomposites with a Covalently Grafted Cellulose-Poly(methyl methacrylate) Interface2019In: Biomacromolecules, ISSN 1525-7797, E-ISSN 1526-4602, Vol. 20, no 2, p. 598-607Article in journal (Refereed)
    Abstract [en]

    A critical aspect in materials design of polymer nanocomposites is the nature of the nanoparticle/polymer interface. The present study investigates the effect of manipulation of the interface between cellulose nanofibrils (CNF) and poly(methyl methacrylate) (PMMA) on the optical, thermal, and mechanical properties of the corresponding nanocomposites. The CNF/PMMA interface is altered with a minimum of changes in material composition so that interface effects can be analyzed. The hydroxyl-rich surface of CNF fibrils is exploited to modify the CNF surface via an epoxide-hydroxyl reaction. CNF/PMMA nanocomposites are then prepared with high CNF content (similar to 38 wt %) using an approach where a porous CNF mat is impregnated with monomer or polymer. The nanocomposite interface is controlled by either providing PMMA grafts from the modified CNF surface or by solvent-assisted diffusion of PMMA into a CNF network (native and modified). The high content of CNF fibrils of similar to 6 nm diameter leads to a strong interface and polymer matrix distribution effects. Moisture uptake and mechanical properties are measured at different relative humidity conditions. The nanocomposites with PMMA molecules grafted to cellulose exhibited much higher optical transparency, thermal stability, and hygro-mechanical properties than the control samples. The present modification and preparation strategies are versatile and may be used for cellulose nanocomposites of other compositions, architectures, properties, and functionalities.

  • 192.
    Bragone, Federica
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Computational Science and Technology (CST).
    Rosén, Tomas
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Morozovska, Kateryna
    KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Computational Science and Technology (CST). KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Sustainability, Industrial Dynamics & Entrepreneurship.
    Laneryd, Tor
    Hitachi Energy, Västerås, Sweden.
    Söderberg, Daniel
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Markidis, Stefano
    KTH, Centres, SeRC - Swedish e-Science Research Centre. KTH, School of Electrical Engineering and Computer Science (EECS), Computer Science, Computational Science and Technology (CST).
    Unsupervised Learning Analysis of Flow-Induced Birefringence in Nanocellulose: Differentiating Materials and ConcentrationsManuscript (preprint) (Other academic)
    Abstract [en]

    Cellulose nanofibrils (CNFs) can be used as building blocks for future sustainable materials including strong and stiff filaments. The goal of this paper is to introduce a data analysis of flow-induced birefringence experiments by means of unsupervised learning techniques. By reducing the dimensionality of the data with Principal Component Analysis (PCA) we are able to exploit information for the different cellulose materials at several concentrations and compare them to each other. Our approach aims at classifying the CNF materials at different concentrations by applying unsupervised machine learning algorithms, like k-means and Gaussian Mixture Models (GMMs). Finally, we analyze the autocorrelation function (ACF) and the partial autocorrelation function (PACF) of the first principal component, detecting seasonality in lower concentrations. The focus is given to the initial relaxation of birefringence after the flow is stopped to have a better understanding of the Brownian dynamics for the given materials and concentrations.

    Our method can be used to distinguish the different materials at specific concentrations and could help to identify possible advantages and drawbacks of one material over the other. 

  • 193.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Deutsches Elektronen Synchrotron, Notkestraße 85, Hamburg, Germany.
    Forslund, Ola Kenji
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Nocerino, Elisabetta
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Kreuzer, L.P
    TU München, Germany.
    Widmann, T.
    TU München, Germany.
    Porcar, L.
    Institut Laue-Langevin, 71 Avenue des Martyrs, Grenoble, France.
    Yamada, N. L.
    High Energy Accelerator Research Organization (KEK), 203-1 Shirakata, Tokai, Naka 319-1106, Japan.
    Matsubara, Nami
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Månsson, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Müller-Buschbaum, P.
    TU München, Germany.
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology. Deutsches Elektronen Synchrotron, Notkestraße 85, Hamburg, Germany.
    Humidity-Induced Nanoscale Restructuring in PEDOT:PSS and Cellulose Nanofibrils Reinforced Biobased Organic Electronics2021In: Advanced Electronic Materials, E-ISSN 2199-160X, Vol. 7, no 6, p. 2100137-, article id 2100137Article in journal (Refereed)
    Abstract [en]

    In times where research focuses on the use of organic polymers as a base for complex organic electronic applications and improving device efficiencies, degradation is still less intensively addressed in fundamental studies. Hence, advanced neutron scattering methods are applied to investigate a model system for organic electronics composed of the widely used conductive polymer blend poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) together with nanocellulose as flexible reinforcing template material. In particular, the impact of relative humidity (RH) on the nanostructure evolution is studied in detail. The implications are discussed from a device performance point of view and the changing nanostructure is correlated with macroscale physical properties such as conductivity. The first humidification (95% RH) leads to an irreversible decrease of conductivity. After the first humidification cycle, however, the conductivity can be reversibly regained when returning to low humidity values (5% RH), which is important for device manufacturing. This finding can directly contribute to an improved usability of emerging organic electronics in daily live.

  • 194.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Forslund, Ola Kenji
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Nocerino, Elisabetta
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Kreuzer, Lucas
    Wiedmann, Tobias
    Porcar, Lionel
    Yamada, Norifumi
    Matsubara, Nami
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Månsson, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Müller-Buschbaum, Peter
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Humidity-induced Nanoscale Restructuring in PEDOT:PSS and Cellulose reinforced Bio-based Organic ElectronicsManuscript (preprint) (Other academic)
  • 195.
    Brett, Calvin J.
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. DESY, Notkestr 85, D-22607 Hamburg, Germany..
    Montani, Annaclaudia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering. Politecn Milan, Dept Chem Mat & Chem Engn Giulio Natta, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Schwartzkopf, M.
    DESY, Notkestr 85, D-22607 Hamburg, Germany..
    van Benthem, R. A. T. M.
    Eindhoven Univ Technol, Lab Phys Chem SPC, Groene Loper 5, NL-5600 MB Eindhoven, Netherlands.;DSM Mat Sci Ctr, Urmonderbaan 22, NL-6167 RD Geleen, Netherlands..
    Jansen, J. F. G. A.
    DSM Mat Sci Ctr, Urmonderbaan 22, NL-6167 RD Geleen, Netherlands..
    Griffini, G.
    Politecn Milan, Dept Chem Mat & Chem Engn Giulio Natta, Piazza Leonardo da Vinci 32, I-20133 Milan, Italy..
    Roth, Stephan Volkher
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Johansson, Mats K.G.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology.
    Revealing structural evolution occurring from photo-initiated polymer network formation2020In: Communications Chemistry, E-ISSN 2399-3669, Vol. 3, no 1, article id 88Article in journal (Refereed)
    Abstract [en]

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

  • 196.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Deutsches Elektronen-Synchrotron DESY, Hamburg 22607, Germany.
    Mittal, Nitesh
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Mechanics.
    Ohm, Wiebke
    Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, 22607, Hamburg, Germany.
    Gensch, Marc
    Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, 22607, Hamburg, Germany.
    Kreuzer, Lucas P.
    Deutsches Elektronen-Synchrotron (DESY), Notkestr. 85, 22607, Hamburg, Germany.
    Körstgens, Volker
    Lehrstuhl für Funktionelle Materialien, Physik-Department, and ¶ Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universitat ̈ München, Garching 85748, Germany.
    Månsson, Martin
    KTH, School of Engineering Sciences (SCI), Applied Physics, Materials and Nanophysics.
    Frielinghaus, Henrich
    Jülich Centre for Neutron Science at MLZ.
    Müller-Buschbaum, Peter
    Lehrstuhl für Funktionelle Materialien, Physik-Department, and ¶ Heinz Maier-Leibnitz Zentrum (MLZ), Technische Universitat ̈ München, Garching 85748, Germany.
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Water-Induced Structural Rearrangements on the Nanoscale in Ultrathin Nanocellulose Films2019In: Macromolecules, ISSN 0024-9297, E-ISSN 1520-5835, Vol. 52, no 12, p. 4721-4728Article in journal (Refereed)
    Abstract [en]

    Many nanoscale biopolymer building blocks with defect-free molecular structure and exceptional mechanical properties have the potential to surpass the performance of existing fossil-based materials with respect to barrier properties, load-bearing substrates for advanced functionalities, as well as light-weight construction. Comprehension and control of performance variations of macroscopic biopolymer materials caused by humidity-driven structural changes at the nanoscale are imperative and challenging. A long-lasting challenge is the interaction with water molecules causing reversible changes in the intrinsic molecular structures that adversely affects the macroscale performance. Using in situ advanced X-ray and neutron scattering techniques, we reveal the structural rearrangements at the nanoscale in ultrathin nanocellulose films with humidity variations. These reversible rearrangements are then correlated with wettability that can be tuned. The results and methodology have general implications not only on the performance of cellulose-based materials but also for hierarchical materials fabricated with other organic and inorganic moisture-sensitive building blocks.

  • 197.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    Mittal, Nitesh
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Ohm, Wiebke
    DESY, Hamburg, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, Hamburg, Germany..
    GISAS study of spray deposited metal precursor ink on a cellulose template2019In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 257Article in journal (Other academic)
  • 198.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. DESY, Photon Sci, Hamburg, Germany.
    Mittal, Nitesh
    KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Ohm, Wiebke
    DESY, Photon Sci, Hamburg, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites. DESY, Photon Sci, Hamburg, Germany..
    In situ self-assembly study in bio-based thin films2018In: Abstracts of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal (Other academic)
  • 199.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.
    Ohm, Wiebke
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Fricke, Bjorn
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany..
    Alexakis, Alexandros Efraim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Coating Technology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center.
    Laarmann, Tim
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Hamburg Ctr Ultrafast Imaging CUI, D-22761 Hamburg, Germany..
    Korstgens, Volker
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Materialien, D-85748 Garching, Germany..
    Muller-Buschbaum, Peter
    Tech Univ Munich, Phys Dept, Lehrstuhl Funkt Materialien, D-85748 Garching, Germany.;Tech Univ Munich, Heinz Maier Leibnitz Zentrum MLZ, D-85748 Garching, Germany..
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Wallenberg Wood Science Center. KTH, School of Engineering Sciences (SCI), Engineering Mechanics. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan, V
    Forschungszentrum Helmholtz Gemeinschaft, Deutsch Elektronen Synchrotron DESY, D-22607 Hamburg, Germany.;Dept Fibre & Polymer Technol, Div Coating Technol, S-10044 Stockholm, Sweden..
    Nanocellulose-Assisted Thermally Induced Growth of Silver Nanoparticles for Optical Applications2021In: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 13, no 23, p. 27696-27704Article in journal (Refereed)
    Abstract [en]

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

  • 200.
    Brett, Calvin
    et al.
    KTH, School of Engineering Sciences (SCI), Engineering Mechanics.
    Ohm, Wiebke
    Fricke, Björn
    Laarmann, Tim
    Körstgens, Volker
    Müller-Buschbaum, Peter
    Söderberg, Daniel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fiberprocesser.
    Roth, Stephan V.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Nanocellulose-Assisted Thermally-Induced Growth of Silver Nanoparticles for Optical ApplicationsManuscript (preprint) (Other academic)
1234567 151 - 200 of 1819
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