The thermodynamic analysis of the effect of pressure on the glass temperature of polystyrene

doi:10.1016/0032-3861(66)90011-5

Polymer

Volume 7, Issue 4, April 1966, Pages 177-191

https://doi.org/10.1016/0032-3861(66)90011-5 Get rights and content

Abstract

The applicability of the equations

$d T_{g} d P = δβ δα = TVδα δC_{p}$

is examined, and it is pointed out that an equivalent procedure is to compare the properties of two glasses formed under different pressures. A detailed analysis is given of published data on the isothermal compression of polystyrene, showing that the first equation fails because a glass formed at 1000 atm is approximately one per cent denser than one formed at atmospheric pressure. Measurements of ΔC_p suggest, however, that the two glasses probably do not differ correspondingly in energy and entropy. The bearing of these conclusions on theories of the glass temperature is briefly discussed.

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^∗: University of Manchester. This analysis was carried out while the author was a fellow of the Michigan Foundation for Advanced Research, Midland, Mich., U.S.A.

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The thermodynamic analysis of the effect of pressure on the glass temperature of polystyrene

Abstract

Rubber Chem. Technol.

J. chem. Phys.

J. chem. Phys.

J. Polym. Sci.

J. Polym. Sci.

J. phys. Chem.

J. phys. Chem.

Kolloidzschr.