Sökning: "ethyl cellulose"

Visar resultat 1 - 5 av 44 avhandlingar innehållade orden ethyl cellulose.

  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. Ethyl Cellulose Membranes used in Modified Release Formulations

    Författare :Johan Hjärtstam; Chalmers tekniska högskola; []
    Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; osmotic pumping; water permeability; drug release; reflectivity; ethyl cellulose; degree of substitution; mechanical strength;

    Sammanfattning : Ethyl cellulose (EC) is a commonly used polymer in modified drug release formulations. The general aim of the present study was to investigate release mechanisms through non-porous EC membranes with hydroxypropyl methyl cellulose (HPMC) contents ranging from 0 to 30% by weight. LÄS MER

  4. 3. 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

  5. 4. Structure control by phase separation and influence on mass transport in films for controlled release

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

    Sammanfattning : Controlled release coatings for oral pharmaceutics are often made of cellulose derivatives. Such coatings can be used to promote a prolonged therapeutic concentration in the blood by a slow drug delivery in the gastrointestinal tract. LÄS MER

  7. 5. Foaming of Some Cellulose Derivatives - Initial Studies

    Författare :Kristina Karlsson; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; rheological characterisation; Foaming; hydroxypropyl methylcellulose HPMC ; scale-up production; ethyl hydroxyethyl cellulose EHEC ; hot-mould baking; cellulose derivatives; extrusion;

    Sammanfattning : Fossil-based polymeric foams, based on polymers such as polystyrene and polyurethane, are important and widely employed materials due to their good mechanical properties relative their low density, the low price and the possibility for large-scale production. There are however a few disadvantages with these foamed products. LÄS MER