Sökning: "etherification"

Visar resultat 1 - 5 av 7 avhandlingar innehållade ordet etherification.

  1. 1. Isolation and chemical modification of arabinoxylan and galactoglucomannan

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Linda Härdelin; [2018]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tg; Films; Material properties; Isolation; Etherification; Modification; PEGylation; Hemicellulose;

    Sammanfattning : Today’s society is based on the use of fossil fuels, where oil is used as transportation fuel and as raw material in the petrochemical industry. Efforts are made to increase the use of bio-based materials, since oil is a non-renewable source and a greenhouse gas contributor. LÄS MER

  2. 2. Synthesis of O-linked Carbasugar Analogues of Galactofuranosides and N-linked Neodisaccharides

    Detta är en avhandling från Stockholm : Department of Organic Chemistry, Stockholm University

    Författare :Jens Frigell; Stockholms universitet.; [2010]
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; carbasugar; galactofuranose; mycobacterium; tuberculosis; ring-closing metathesis; GlfT2; galactan; epoxide-opening; pseudodisaccharide; etherification; regioselective; carbohydrate; carbocycles; glycomimetics; glucosidase; neodisaccharides; Mitsunobu; NATURAL SCIENCES Chemistry Organic chemistry Organic synthesis; NATURVETENSKAP Kemi Organisk kemi Organisk syntes; organisk kemi; Organic Chemistry;

    Sammanfattning : In this thesis, carbohydrate mimicry is investigated through the syntheses of carbohydrate analogues and evaluation of their inhibitory effects on carbohydrate-processing enzymes.Galactofuranosides are interesting structures because they are common motifs in pathogenic microorganisms but not found in mammals. M. LÄS MER

  3. 3. Chemical modification of cellulose-new possibilities of some classical routes

    Detta är en avhandling från Gothenburg : Chalmers tekniska högskola

    Författare :Merima Hasani; [2010]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Cellulose esters; Cellulose characterization; Cellulose ethers; Cationization; Cellulose nanocrystals; Crosslinking of cellulose;

    Sammanfattning : Owning to its unique structure, along with the inexhaustible renewability, cellulose has been a subject of scientific and commercial interest for over 150 years. However, given attractive structural properties, such as stiffness, hydrophilicity, stereoregularity, potential for chemical modifications and ability to form superstructures, utilization of this biopolymer is far below its potential. LÄS MER

  4. 4. Mercerization and Enzymatic Pretreatment of Cellulose in Dissolving Pulps

    Detta är en avhandling från Karlstad : Karlstads universitet

    Författare :Heléne Almlöf Ambjörnsson; Karlstads universitet.; [2013]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; alkali; carboxymethyl cellulose; cellulose I; cellulose II; cellulose dissolution; degree of substitution; enzymatic treatment; filterability; gel formation; mercerization; multivariate analytical methods; NIR FT Raman spectroscopy; sodium hydroxide; zink oxide; Chemical Engineering; Kemiteknik;

    Sammanfattning : This thesis deals with the preparation of chemically and/or enzymatically modified cellulose. This modification can be either irreversible or reversible. Irreversible modification is used to prepare cellulose derivatives as end products, whereas reversible modification is used to enhance solubility in the preparation of regenerated cellulose. LÄS MER

  5. 5. Extended Mercerization Prior to Carboxymethyl Cellulose Preparation

    Detta är en avhandling från Karlstad : Karlstad University

    Författare :Heléne Almlöf; Karlstads universitet.; [2010]
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carboxymethyl cellulose; Mercerization; DS; FT Raman spectroscopy; Filtration ability; TECHNOLOGY Chemical engineering; TEKNIKVETENSKAP Kemiteknik; Chemical Engineering; Kemiteknik;

    Sammanfattning : Carboxymethyl cellulose (CMC) is produced commercially in a two-stage process consisting of a mercerization stage, where the pulp is treated with alkali in a water alcohol solution, followed by an etherification stage in which monochloroacetic acid is added to the pulp slurry. In this thesis an extended mercerization stage of a spruce ether pulp was investigated where the parameters studied were the ratio of cellulose I and II, concentration of alkali, temperature and retention time. LÄS MER