Einfluà von wasserlöslichen und wasserunlöslichen Weichmachern auf die thermomechanischen Eigenschaften von magensaftresistenten FilmüberzügenAlfred Fetscher und Peter Christian Schmidt Pharmazeutisches Institut der Eberhard-Karls-Universität Tübingen, Pharmazeutische Technologie, Tübingen Influence of Water Soluble and Water Insoluble Plasticizers on the Thermal and Mechanical Properties of Methacrylate-copolymer Films The effect of two different types of plasticizers on the thermal and mechanical properties of methacrylate-copolymers was studied. The efficiency of the plasticization was studied by determining the dependance of the minimum film forming temperature, the glass transition temperature and the elasticity of the films on the plasticizersâ concentration and aqueous solubility. The effect of both plasticizers, dibutyl phthalate and triethyl citrate, on the thermal properties of methacrylic acid methylmethacrylate methylacrylate copolymer (Polymer 4110 D) showed a strong correlation with the concentration of the plasticizer. The brittleness of the films decreased while increasing the plasticizer concentration. The film surfaces were smooth and homogeneous. In relation to the water soluble triethyl citrate, dibutyl phthalate, almost water insoluble, caused different thermal and mechanical properties of ethylacrylate methacrylic acid copolymer (Eudragit L 30 D-55). Dibutyl phthalate had a low effect on reducing the minimum film forming temperature and glass transition temperature. The surfaces of the Polymers were smooth and homogeneous indicating complete film formation. Key words Glasübergangstemperatur · Methacrylsäure-Copolymer · Mindestfilmbildetemperatur · Rasterelektronenmikroskopie · Rastersondenmikroskopie |
© ECV- Editio Cantor Verlag (Germany) 1999 |
pharmind 1999, Nr. 1, Seite 69