Regensburg 2007 – wissenschaftliches Programm
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CPP: Fachverband Chemische Physik und Polymerphysik
CPP 20: POSTER: Biological Systems + New Materials
CPP 20.12: Poster
Mittwoch, 28. März 2007, 16:00–18:30, Poster B
Rigid amorphous fraction in polymer nano-composites — •Albert Sargsyan1,2, Anahit Tonoyan2, Sevan Davtyan2, and Christoph Schick1 — 1Institute of Physics, University of Rostock, Germany — 2State Engineering University of Armenia, Yerevan, Armenia
It is frequently reported that semicrystalline polymers show significantly smaller relaxation strength at glass transition than expected from the non-crystalline fraction. This observation could be explained by the introduction of a rigid amorphous fraction (RAF) which contributes neither to the heat of fusion or X-ray crystallinity nor to the relaxation strength at glass transition, see [1] for a review. The RAF is assumed to be in a glassy state above the common glass transition temperature. From heat capacity the temperature and time dependence of the RAF can be obtained. Polymer nano-composites can be used as such a model structure if they exhibit a RAF. If the polymer nano-particle interaction is strong enough there may be a significant RAF because of the large surface area of the nano-particles. The main advantage lies in the fact that the part causing the immobilization of the polymer molecules, i.e. the nano-additive, does not melt or crystallize in the relevant temperature range. So the essential disturbing factor for a direct observation of the devitrification is excluded. This may allow determining the devitrification of the RAF in polymer nano-composites by using calorimetric methods. The most recent data on this work is presented