Sökning: "POLYESTERS"

Visar resultat 1 - 5 av 64 avhandlingar innehållade ordet POLYESTERS.

  1. 1. Suberin based polyesters

    Författare :Ann Olsson; Monica Ek; Mats Johansson; Margaretha Söderqvist; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cellulose and paper engineering; Cellulosa- och pappersteknik;

    Sammanfattning : In the wish to replace oil-based chemicals and materials with such based on biodegradable and renewable resources, this work has been performed. In a biorefinary concept, waste birch bark from paper pulp mills and timber production has been evaluated as a potential source for polyesters. LÄS MER

  3. 2. Novel methods to synthesize aliphatic polyesters of vivid architectures

    Författare :Rajiv Srivastava; Ann-Christine Albertsson; Ronnie Palmgren; KTH; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polyesters; 1; 5-dioxepan-2-one; Caprolactone; Sn Oct 2; Enzyme; Lipase-CA; Ring-Opening Polymerization; Architecture; Tissue Engineering; Polymer chemistry; Polymerkemi;

    Sammanfattning : Cross-linked films of ε-caprolactone (CL) and 1,5-dioxepan-2-one (DXO) having various mole fractions of monomers and different cross-link densities were prepared using 2,2’-bis-(-caprolactone-4-yl) propane (BCP) as cross-linking agent and Sn(Oct)2 as catalyst. Reaction parameters were examined to optimize the film-forming conditions. LÄS MER

  4. 3. Towards sugar- and lignin-based polyesters and polyurethanes with enhanced properties

    Författare :Niklas Warlin; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polyesters; Polyurethane; Bio-based Materials; HMF; Recycling; Vanillin;

    Sammanfattning : The enormous production and consumption of fossil-based plastics has caused severe environmental challenges such as pollution of the ocean, increased CO2-emissions, and various health problems. Many ofthese concerns are intimately connected to the use of fossil fuels in the production of polymers. LÄS MER

  5. 4. Lipase-Catalyzed Syntheses of Telechelic Polyesters

    Författare :Magnus Eriksson; Karl Hult; Mats Martinelle; Sergio Riva; KTH; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Candida antarctica lipase B; lipase-catalysis; polymerization; telechelic; functional polyesters; ring-opening polymerization; polycondensation.; Biochemistry; Biokemi;

    Sammanfattning : Telechelic polyesters have successfully been synthesized with lipase-catalyzed polymerization. The produced telechelics had a high degree of di­functionalization, high purity (requiring little or no workup) and controlled degree of polymerization. The syntheses were performed in one-pot one-step reaction systems. LÄS MER

  7. 5. Toward Biomass-Derived Recyclable Polyesters

    Författare :Smita Vamdev Mankar; Centrum för analys och syntes; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polyester; polycondensation; spiroacetal; chemical recycling; enzymatic degradation;

    Sammanfattning : Fossil-based plastics have become a matter of concern due to their negative environmental impacts such as greenhouse gas emissions and threats to the health of living beings. Alternative polymers derived from sustainable biomass resources have thus become an attractive research field since the last decade. LÄS MER