Search for dissertations about: "polymer diffusion"

Showing result 1 - 5 of 176 swedish dissertations containing the words polymer diffusion.

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

    Author : Helene Andersson; Chalmers tekniska högskola; []
    Keywords : 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;

    Abstract : 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. READ MORE

  4. 2. Small Molecule Diffusion in Spherulitic Polyethylene : Experimental Results and Simulations

    Author : Alessandro Mattozzi; Ulf W. Gedde; Alan H. Windle; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; diffusion; polyethylene; poly ethylene-co-octene ; free volume; morphology; intermediate phase; spherulite; Monte Carlo simulation; Polymer chemistry; Polymerkemi;

    Abstract : The diffusion of small-molecule penetrants in polyethylene is hindered by impenetrable crystals and by the segmental constraints imposed by the crystals on the penetrable phase. Liquid and vapour n-hexane sorption/desorption measurements were performed on metallocene catalyzed homogenous poly(ethylene-co-octene)s. READ MORE

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

    Author : Artur Hedlund; Chalmers tekniska högskola; []
    Keywords : 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;

    Abstract : 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. READ MORE

  6. 4. Influence of liquid diffusion on the performance of polymer materials in industrial applications

    Author : Stefanie Römhild; Mikael Hedenqvist; Lars Berglund; KTH; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; LCP; Vectra A950; thermoset resin; FRP; diffusion; disclination; annealing; lining; bonding; long-term properties in water; Polymer chemistry; Polymerkemi;

    Abstract : Diffusion of liquids into and through polymers is an important factor that negatively may influence the durability or lifetime of a polymer structure used in industrial applications. In this work two types of polymers, a liquid crystalline polymer (LCP, Vectra A950) and various thermoset resins as used in fibre reinforced plastics (FRP) process equipment were studied with regard to barrier properties, chemical resistance and long-term performance. READ MORE

  7. 5. Structure-Performance Relations of Oxygen Barriers for Food Packaging

    Author : Åsa Nyflött; Magnus Lestelius; Ellen Moons; Lars Järnström; Carlsson Kvarnlöf Gunilla; Chris Bonnerup; José Maria Lagaron; Karlstads universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Barrier coating; Permeability; Dynamic Mass Transport; Modelling; Diffusion; Polymer; Dispersion; Kaolin; LCA; Starch; Hemicellulose; Materials Science; Materialvetenskap;

    Abstract : Food packaging should ensure the safety and quality of food, minimize spoilage and provide an easy way of storing and handling it. Barrier coatings are generally used to meet the demands placed on fibre-based food packages, as these have the ability to regulate the amount of gases that can enter them. READ MORE