Sökning: "pulp and paper technology"
Visar resultat 21 - 25 av 431 avhandlingar innehållade orden pulp and paper technology.
21. Processing and properties of thermoplastic composites containing cellulose nanocrystals or wood-based cellulose fibres
Sammanfattning : Cellulose nanocrystals (CNC) were surface modified with dialkylamines to increase the compatibility between the CNC and the polymeric matrix, and promising results were obtained, with a 300 % stiffness increase when the mixed dispersion was compression moulded on a laboratory scale. The manufacturing process was up-scaled using water-assisted mixing in a twin-screw extruder (TSE) followed by a second compounding step and injection moulding (IM). LÄS MER
22. Dimensional Stability of Paper : Influence of Fibre-Fibre Joints and Fibre Wall Oxidation
Sammanfattning : Papper är ett mycket mångsidigt material. Trots detta finns det ett flertal egenskaper som begränsar papperets användbarhet. Ett av de större problemen med cellulosa- och lignocellulosafibrer är att de sänker sin fria energi genom att sorbera vatten, och denna sorption förändrar papperets dimensioner. LÄS MER
23. Xylan Reactions in Kraft Cooking : Process and Product Considerations
Sammanfattning : Xylan is the main hemicellulose in birch, eucalyptus, and most other hardwood species. During kraft pulping a series of chemical reactions and physical processes involving xylan takes place. LÄS MER
24. Biocomposites Based on Core-Shell Cellulose Nanofibers : Preparation, Structure, and Properties
Sammanfattning : Cellulose nanofibers (CNFs) are of interest as load-bearing components for polymer matrix nanocomposites. A wide range of nanostructured materials including nanopaper/films, foams, aerogels, and hydrogels can be prepared from CNFs. The material performance can be fine-tuned when CNFs are combined with different polymer matrices. LÄS MER
25. Molecular orientation in cellulose fibers and composites
Sammanfattning : 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. LÄS MER