Search for dissertations about: "lignin chemistry"

Showing result 1 - 5 of 102 swedish dissertations containing the words lignin chemistry.

  2. 1. Palladium-catalyzed lignin valorization : Towards a lignin-based biorefinery

    Author : Maxim Galkin; Joseph Samec; Rafael Luque; Uppsala universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; Lignin; Heterogeneous Catalysis; Palladium; Biomass; Depolymerization; Reduction; Oxidation; Biorefinery; Transfer Hydrogenolysis; Organic Chemistry; Organisk kemi;

    Abstract : The work described in this thesis focuses on the cleavage of the β-O-4′ bond, which is the most abundant interunit linkage in the lignin polymer.In the first part, three methods based on palladium catalysis have been developed and their applicability has been verified using lignin model compounds. READ MORE

  4. 2. Lignin-Based Thermosets with Tunable Mechanical and Morphological Properties : A Study of Structure-Property Relationships

    Author : Iuliana Ribca; Mats Johansson; Martin Lawoko; Stephan V. Roth; Mika Sipponen; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Softwood; hardwood; technical lignin; solvent fractionation; allylation; thiol-ene thermosets; thioether linkage; wide-angle X-ray scattering; π-π stacking interactions; Barrträ; lövträ; tekniskt lignin; lösningsmedelsfraktionering; allylering; tiol-en-härdplaster; tioeterbindning; vidvinkelröntgenspridning; π-π staplingsinteraktioner; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Abstract : Nowadays, there is an urgent need to decrease our dependence on fossilresources and shift towards the use of renewable resources for advancingsustainable development. Utilizing renewable and bio-based raw materials,such as lignocellulosic biomass, for designing new materials is a promisingapproach to promote this objective. READ MORE

  5. 3. Additive-Driven Improvements in Interfacial Properties and Processing of TMP-Polymer Composites

    Author : Seyedehsan Hosseini; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL 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; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; molybdenum disulfide; magnesium stearate; thermomechanical pulp; alkyl ketene dimer; friction; rheology;

    Abstract : Efforts to address environmental concerns have resulted in new regulations designed to plan the reduction of plastic and synthetic polymer usage, necessitating the search for sustainable natural alternatives with comparable cost-effectiveness and mechanical performance. Thermomechanical pulp (TMP) fibres are one of the most affordable natural fibres that have no chemical refining in production, production have a high yield of 90-98% and TMP fibres have been demonstrated to improve the mechanical characteristics (strength, stiffness and toughness) of wood-polymer composites (WPCs) compared to the pure polymer. READ MORE

  6. 4. Molecular orientation in cellulose fibers and composites

    Author : Leo Svenningsson; Chalmers tekniska högskola; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite; molecular orientation; lignin; solid-state NMR; Raman spectroscopy; fibers; X-ray scattering; carbon fibers; regenerated cellulose;

    Abstract : The scope of this thesis is to quantitatively investigate the molecular orientation distribution of regenerated cellulose fibers and composites. The molecular orientation is known to affect macroscopic properties such as tensile strength of the fiber. READ MORE

  7. 5. Fractionation of woody biomass : lignin and suberin in focus

    Author : Ivan Kumaniaev; Joseph Samec; Claudia Crestini; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; lignocellulose; lignin; suberin; biomass; palladium; catalysis; flow chemistry; organisk kemi; Organic Chemistry;

    Abstract : This thesis is dedicated to the research of fractionation and valorization of different types of woody biomass. In the first part, oak (Quercus suber) and birch (Betula pendula) barks are considered. Bark is the outer layer of wood and is treated as waste in the current wood processing technologies. READ MORE