Sökning: "cellulose materials"

Visar resultat 1 - 5 av 508 avhandlingar innehållade orden cellulose materials.

  1. 1. Mass Transport through Phase Separated Films - Effects of Ethyl Cellulose Molecular Weight on Cellulose Derivative Blends for Pharmaceutical Coatings

    Författare :Helene Andersson; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Coating; Ethyl cellulose; Diffusion; Mass transport; Solvent evaporation; Molecular weight; Phase separation; Film; Hydroxypropyl cellulose; Polymer blend; Cellulose derivatives; Controlled release;

    Sammanfattning : Polymer blends are utilized for a variety of applications, not least in pharmaceutical coatings for controlled release of drugs. For instance, blends of ethyl cellulose (EC) and the water-soluble hydroxypropyl cellulose (HPC) can be used to coat drug pellets for oral extendedrelease formulations. LÄS MER

  3. 2. Coagulation of Cellulose: from Ionic-Liquid Solution to Cellulose Nanostructure

    Författare :Artur Hedlund; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Wet Spinning; Cellulose; Ionic Liquids; Diffusion; Coagulation; Nonsolvent;

    Sammanfattning : Abstract A linear chain of glucose monomers, cellulose, provides the structural reinforcement of the cell walls of plants and constitutes almost half of their dry mass. Wood and other plant-based raw materials are processed on a large industrial scale to isolate the cellulose, which is then dissolved. LÄS MER

  4. 3. Engineering of lignin in wood towards functional materials

    Författare :Gabriella G. Mastantuoni; Qi Zhou; Lars Berglund; Jean-Marie Raquez; KTH; []
    Nyckelord :LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Cellulose; wood; nanotechnology; sulfonation; biocomposite; cross-linking; densification; transparent film; wood foam; conductivity; Cellulosa; trä; nanoteknologi; sulfonering; biokomposit; tvärbindning; förtätning; transparent film; poröst trämaterial; konduktivitet; Fiber- och polymervetenskap; Fibre and Polymer Science;

    Sammanfattning : Through 270 million years of evolution, the finely tuned hierarchical structure of wood has been optimized for efficient nutrient transport and exceptional mechanical stability. Its distinctive orthotropic constitution can provide inspiration and design opportunities for the development of novel functional materials. LÄS MER

  5. 4. Microfibrillated cellulose : Energy-efficient preparation techniques and key properties

    Författare :Mikael Ankerfors; Lars Wågberg; Minna Hakkarainen; Paul Gatenholm; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Microfibrillated cellulose; microfibrillar cellulose; nanofibrillated cellulose nanofibrillar cellulose; nanocellulose; MFC; NFC; production techniques; energy efficient; gel properties; films; enzymes; carboxymethylation; carboxymethyl cellulose; CMC; mechanical properties; oxygen barrier; homogenization;

    Sammanfattning : This work describes three alternative processes for producing microfibrillated cellulose (MFC) in which pulp fibres are first pre-treated and then homogenized using a high-pressure homogenizer. In one process, fibre cell wall delamination was facilitated with a combined enzymatic and mechanical pre-treatment. LÄS MER

  7. 5. 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