Sökning: "cellulose ether"

Visar resultat 1 - 5 av 19 avhandlingar innehållade orden cellulose ether.

1. 1. Experimental study of alkalinisation of cellulose in industrial relevant conditions

   Författare :Diana Carolina Reyes Forsberg; Ola Sundman; Bertil Eliasson; Ulf Germgård; Umeå universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; Mercerisation; Alkalinisation; Cellulose I; Cellulose II; Alkali cellulose; Viscose; Cellulose ether; Carboxymethylcellulose; Sodium glycolate; Sodium diglycolate; Raman spectroscopy;

   Sammanfattning : Mercerisation of cellulose pulp with a solution of NaOH is the first step of manufacturing cellulose-based value-added products, e.g. viscose fibres and cellulose ethers. During this process, cellulose transforms into a swollen crystalline structure, alkali cellulose (Na-Cell). LÄS MER

3. 2. Characterization of cellulose pulps and the influence of their properties on the process and production of viscose and cellulose ethers

   Författare :Peter Strunk; Bertil Eliasson; Roland Adden; Umeå universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; cellulose ether; dissolving pulp; ethyl hydroxyethyl cellulose; hardwood; multivariate data analysis; reactivity; softwood; sulfate; sulfite; viscose;

   Sammanfattning : Today’s market offers an ever-increasing range of cellulose pulps (derivative pulps) made fromvarious wood types through different delignification processes. Each pulp segment has its uniquecharacteristics, which makes it difficult for the producer of cellulose derivatives to choose the mostsuitable pulp for optimum processability and product quality. LÄS MER

4. 3. Mass spectrometric studies of cellulose ethers

   Författare :Dane Momcilovic; Centrum för analys och syntes; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Polymerteknik; biopolymers; Polymer technology; Analytisk kemi; Analytical chemistry; enzymatic depolymerisation; reductive amination; electrospray ionisation; cellulose ethers; MALDI; mass spectrometry;

   Sammanfattning : Cellulose based derivatives, such as cellulose ethers, today find many applications in a diverse range of fields. The numerous applications put high demands on the technological performance of the cellulose ethers. LÄS MER

5. 4. Extended Mercerization Prior to Carboxymethyl Cellulose Preparation

   Författare :Heléne Almlöf; Ulf Germgård; Björn Kreutz; Monica Ek; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Carboxymethyl cellulose; Mercerization; DS; FT Raman spectroscopy; Filtration ability; Chemical engineering; 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

7. 5. Tailoring Surface Properties of Bio-Fibers via Atom Transfer Radical Polymerization

   Författare :Josefina Lindqvist; Eva Malmström; Steven Rannard; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; cellulose; bio-fiber; atom transfer radical polymerization; surface modification; grafting; polymer brushes; functional surfaces; superhydrophobic; stimuli-responsive; Polymer chemistry; Polymerkemi;

   Sammanfattning : The potential use of renewable, bio-based polymers in high-technological applications has attracted great interest due to increased environmental concern. Cellulose is the most abundant biopolymer resource in the world, and it has great potential to be modified to suit new application areas. LÄS MER