Sökning: "Wood pulp fibres"

Visar resultat 21 - 25 av 65 avhandlingar innehållade orden Wood pulp fibres.

1. 21. Polyelectrolyte Complexes : Their Characterization and use for Modification of Wood Fibre Surfaces

   Författare :Linda Gärdlund; Lars Wågberg; Robert Pelton; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cellulose and paper engineering; Cellulosa- och pappersteknik; Cellulosa- och pappersteknik; Chemical engineering;

   Sammanfattning : For economical reasons filler particles and less expensive fibre raw materials are more frequently used in papermaking. This influences the mechanical properties of the formed papers in a negative way and it is therefore necessary to add strength-enhancing agents to the papermaking furnish. LÄS MER

3. 22. Aspects of optimizing pulp fibre properties for tissue and packaging materials

   Författare :Hafizur Rahman; Armando Cordova; Per Engstrand; Börje Norlin; Göran Bengtsson; Mittuniversitetet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

   Sammanfattning : To improve the competitive advantages of pulp fibre-based materials for tissue and packaging over fossil-based products, it is essential to increase knowledge of the selectivity of the cooking and the chemimechanical processes by optimizing the unit operations of impregnation, cooking and refining. A general goal in pulping processes is to achieve as efficient and even fibre separation as possible. LÄS MER

4. 23. Chromatographic separation of wood constituents

   Författare :Niklas Westerberg; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; biorefinery; mathematical modelling.; Norway spruce; separation; chromatography;

   Sammanfattning : In a modern kraft pulp mill only about 45 % of the incoming wood is present in the pulp and it is mainly composed of cellulose. The remainder of the wood, which is dissolved in order to liberate the cellulose fibres, e.g., hemicellulose and lignin, ends up in the mill´s recovery boiler to recover the latent energy. LÄS MER

5. 24. Absorbent Materials from Kraft Pulp

   Författare :Fredrik Wernersson Brodin; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MFC; retention; foam; TEMPO oxidation.; absorption; Absorbent;

   Sammanfattning : Superabsorbent polymers (SAP) have, since being introduced in the 1980s, become an important constituent in hygiene products, such as disposable diapers. The design of disposable diapers has changed over the years and today thinner products can be produced partly because of the excellent absorption and retention properties of the petrochemical-based SAP. LÄS MER

7. 25. Preparation and characterization of nanoporous cellulose fibres and their use in new material concepts

   Författare :Anna Sjöstedt; Lars Wågberg; Akira Isogai; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Fiber- och polymervetenskap; Fibre and Polymer Science;

   Sammanfattning : The overall objective of the work in this thesis is to better utilize the non-collapsed structure of the delignified wood-fibre cell wall in the preparation of new types of materials.In order to utilize the fibres in new materials, it is crucial to have a well-defined starting material and to know how it reacts to certain treatments of the fibres. LÄS MER