Effects of High Pressure on Amorphous Polymers. II. Annealing of Densified Polymethyl Methacrylate
- 1 April 1971
- journal article
- research article
- Published by AIP Publishing in Journal of Applied Physics
- Vol. 42 (5) , 1892-1896
- https://doi.org/10.1063/1.1660464
Abstract
The annealing at atmospheric pressure of polymethyl methacrylate (PMMA) densified in various pressure‐temperature‐time cycles has been examined in the temperature range 25°–90°C. PMMA densified in the glassy state was found to be less stable than that densified by cooling through the glass transition under pressure, in agreement with previous results on inorganic glasses. Moreover, the relative stability of densified PMMA depended on the sample residence time in the glass transition region at pressure. In the one case where an energyspectrum for annealing could be calculated, the data indicated a multiplicity of molecular processes with activation energies in the range 14–19 kcal/mole.This publication has 10 references indexed in Scilit:
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