Sökning: "Cellulose esters"

Visar resultat 1 - 5 av 10 avhandlingar innehållade orden Cellulose esters.

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

   Författare :Merima Hasani; Chalmers tekniska högskola; []
   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

3. 2. Interactions Between Water and Cellulose Esters

   Författare :Robin Nilsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; cellulose acetate; wide-angle X-ray scattering; water absorption; Hansen Solubility Parameters; glass transition; water diffusion;

   Sammanfattning : Biopolymers, which are produced from natural sources, are gaining interest as a potential replacement for fossil-based polymers. As such, they are already widely used in several industries, including the food, healthcare, and personal care industries. LÄS MER

4. 3. An Investigation of Mixed Cellulose Esters and Acyclic Polyacetates: Effects of Side-Chain Lengths and Degrees of Ring-Opening

   Författare :Robin Nilsson; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; water interactions; oxygen permeation; storage modulus; ring-opening; water sorption; cellulose esters; side-chains; acyclic cellulose acetate;

   Sammanfattning : Bio-based polymers produced from natural sources are gaining an increased interest as potential replacement for today’s conventional fossil-based plastic polymers. Their use is already wide in many large-scale industrial areas such as healthcare, personal care, and food. LÄS MER

5. 4. Shapeable cellulosic materials

   Författare :Malin Brodin; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; composite; polyethylene; coagulation; material properties; cellulose ester; interactions; gel; cellulose; ionic liquid;

   Sammanfattning : ABSTRACTA palette of materials has been developed by the oil and gas sector. The expected depletion of fossil resources and the stress on the climate from burning them has, however, turned the world’s attention to renewable resources. LÄS MER

7. 5. The initial phase of sodium sulfite pulping of softwood : A comparison of different pulping options

   Författare :Raghu Deshpande; Ulf Germgård; Pedro Fardim; Karlstads universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Activation energy; acid sulfite pulping; bisulfite pulping; cellulose; delignification; dissolving pulp; extractives; glucomannan; hemicelluloses; lignin; lignin condensation; lignin carbohydrate complexes; pine; spruce; thiosulfate; total SO2; xylan; Chemical Engineering; Kemiteknik;

   Sammanfattning : Single stage and two-stage sodium sulfite cooking were carried out on either spruce, pine or pure pine heartwood chips to investigate the influence of several process parameters on the initial phase of such a cook down to about 60 % pulp yield. The cooking experiments were carried out in the laboratory with either a lab-prepared or a mill-prepared cooking acid and the temperature and time were varied. LÄS MER