Sökning: "Wood polymers"

Visar resultat 1 - 5 av 85 avhandlingar innehållade orden Wood polymers.

  1. 1. Engineering of lignin in wood towards functional materials

    Författare :Gabriella G. Mastantuoni; Qi Zhou; Lars Berglund; Jean-Marie Raquez; KTH; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cellulose; wood; nanotechnology; sulfonation; biocomposite; cross-linking; densification; transparent film; wood foam; conductivity; Cellulosa; trä; nanoteknologi; sulfonering; biokomposit; tvärbindning; förtätning; transparent film; poröst trämaterial; konduktivitet; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Through 270 million years of evolution, the finely tuned hierarchical structure of wood has been optimized for efficient nutrient transport and exceptional mechanical stability. Its distinctive orthotropic constitution can provide inspiration and design opportunities for the development of novel functional materials. LÄS MER

  3. 2. Acid-catalyzed Liquefaction of Industrial Side-streams for Producing Wood Adhesives and Particleboard

    Författare :Wen Jiang; Stergios Adamopoulos; Sheikh Ali Ahmed; Sergej Medved; Carsten Mai; Johannes Konnerth; Linnéuniversitetet; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Bark; Catalysts; Industrial side-streams; Liquefaction; Oat husks; Optimization; Particleboards; Polyurethane; Polyhydric alcohols; Wood adhesives; Wood sawdust; Forestry and Wood Technology; Skog och träteknik;

    Sammanfattning : Big quantities of residues and side-streams are generated annually from forest-based and agricultural industries all around the world and present a relatively unexplored renewable resource. Due to the absence of a regularly updated and systematic database of supply, industrial residues and side-streams usually end up in landfill disposal, are used for energy generation, or remain at the production sites. LÄS MER

  4. 3. Adhesion to machined and laser ablated wood surfaces

    Författare :Micael Stehr; KTH; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; ablation; adhesion; checks; coating; cracks; excimer laser; gluing; IR laser; mechanical machining; mechanical weak boundary layer; microscopy; notched specimens; pine; planing; sample preparation; sawing; scanning electronmicroscopy; spruce; tip-cracks; UV laser; weak boundary layer; wood;

    Sammanfattning : This thesis is a contribution to the R&D-program ValueActivation at KTH,Division of Wood Technology and Processingand containsfive papers related to the evaluation and development ofmachining techniques (mechanical and irradiation treatments)whereby weak boundaries at the wood surfaces in the form of(mechanical) weak boundary layers and (micro) cracks due tomechanical treatment can be avoided.The first paper describes the development of a method–using a UV laser–to study the mechanically weakenedboundaries. LÄS MER

  5. 4. Local variability in chemical and physical properties of spruce wood fibers

    Författare :Anna Bergander; KTH; []
    Nyckelord :cell walls; chemical composition; elastic constants; elastic strength; Fiber properties; Fibril angles; Mathematical models; Microscopy techniques; Picea Abies; Stiffness; Tensile properties; Wood polymers; Wood;

    Sammanfattning : Wood is well known to be a heterogeneous native materialwith large variations in its composite properties, includingvariations whose origins have not yet been completelyidentified. Traditionally, the macroscopic variations in woodhave received the most attention; for example, the variation indensity from the pith to the bark in trees. LÄS MER

  7. 5. Dynamic Mechanical Studies of Wood, Paper and some Polymers Subjected to Humidity Changes

    Författare :Reza Ebrahimzadeh Pirshahid; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; wood; paper; mechanosorption; hygroscopic polymers; PEO; cellophane; PVAc; PA6; diffusion; dynamic mechanical properties;

    Sammanfattning : The dynamic mechanical response of several hygroscopic materials including wood (Scots pineveneer), paper (unbleached sulphate), cellophane, polyamide 6 (PA6) and poly(vinyl acetate)(PVAc) have been studied especially under conditions of a stepwise varying humidity in the atmosphere surrounding the samples. In all cases the in phase and out of phase components of the force necessary to achieve a given deformation were measured for various oscillation frequencies (from 0. LÄS MER