Sökning: "native cellulose"

Visar resultat 1 - 5 av 54 avhandlingar innehållade orden native cellulose.

  1. 1. Cellulose processing in ionic liquid based solvents

    Författare :Carina Olsson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; esterification; cellulose; NMR spectroscopy; solution spinning; dissolution; ionic liquids; cellulose derivatives; rheology; crystallinity;

    Sammanfattning : As the most abundant polymer in nature, cellulose has an undisputed role among the raw materials to be used in a sustainable future. From its native form, in wood or straw, cellulose can be processed into products such as paper and board. LÄS MER

  3. 2. Engineering of Native Cellulose Structure for Pharmaceutical Applications : Influence of Cellulose Crystallinity Index, Surface Area and Pore Volume on Sorption Phenomena

    Författare :Albert Mihranyan; Ragnar Ek; Maria Strømme; Hans Leuenberger; Uppsala universitet; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Pharmaceutics; microcrystalline cellulose; Cladophora sp. algae; crystallinity index; surface area and pore volume; fractals; stability; Galenisk farmaci; Pharmaceutics; Galenisk farmaci;

    Sammanfattning : Cellulose powders from various sources were manufactured and characterized to investigate the influence of their crystallinity index, surface area, and pore volume on sorption phenomena and the relevant pharmaceutical functionality. The influence of the cellulose crystallinity index on moisture sorption was important at low and intermediate relative humidities. LÄS MER

  4. 3. Investigating structural changes of cellulose using NMR spectroscopy

    Författare :Alexander Idström; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; crystallinity index; NCC; ionic liquids; CP MAS 13C-NMR; hornification; native cellulose; regenerated cellulose; NMR cryoporometry; pulp; Solid-state NMR;

    Sammanfattning : In this thesis solid-state NMR and NMR cryoporometry were used to gain information of the structure of cellulose. Measurements were conducted on both native and regenerated cellulose, exposed to a range of different treatments. LÄS MER

  5. 4. Nanostructured Cellulose Biocomposites : Effects from dispersion, network and interface

    Författare :Mohd Farhan Ansari; Lars Berglund; Jean-Francois Gerard; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wood; cellulose nanofibrils; hygromechanical properties; network structure; thermoset; polymer matrix composites; natural fiber composites; pulp fiber; strain hardening; humidity; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : The major load bearing component in native wood, cellulose nanofibrils, are potential candidates for use as reinforcement in polymer matrices. This study is based on nanocellulose composites and attempts to prepare and characterize biocomposites with high nanocellulose content and investigate the influence of nanostructure on macroscopic properties. LÄS MER

  7. 5. Investigating cellulose structure using solid-state NMR spectroscopy

    Författare :Alexander Idström; 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; CNC; crystallinity index; regenerated cellulose; 2D NMR; native cellulose; pulp; Solid-state NMR; ionic liquids; CP MAS 13C-NMR; hornification;

    Sammanfattning : Cellulose is the most abundant polymer in nature and it is an important constituent in most flowers, trees, and even some animals. Cellulose has an established use in many important products, such as textile fibers, paper and paperboard, and recently new applications have received increased attention. LÄS MER