Study of relaxation time of mechanically aligned polystyrene thin films
by Kai Pong Shiu
THESIS
2003
M.Phil. Physics
viii, 23 leaves : ill. ; 30 cm
Abstract
The relaxation times distribution of molecular alignments in polymers induced by mechanically rubbing with velvet cloth was found to be different from those induced by other means of mechanical deformation, e.g. hot drawing. Several attempts have been made but failed to achieve a complete model in describing the relaxation times distribution. In this thesis, we are going to introduce a new mathematical model to determine the distribution. The model is supported by experimental results. The relaxation was also found independent of its thermal history which is e.g., raising and lowering the temperature of the sample several times, and independent of the rubbing history.
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