The glass transition behaviour and thermodynamic properties of amorphous polystyrene

Date

1989-12

Author

Aras, Leyla
Richardson, Maxwell J.

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The effect of molecular weight (MW) and thermal history on the heat capacity (cp) of amorphous polystyrene over the temperature range from 200–440 K has been measured using differential scanning calorimetry (d.s.c.) General equations are given that show the influence of MW on cp in both the glassy and liquid states. An enthalpic definition of the glass temperature reflects changes in the glass structure, due to thermal history, that are not found using conventional d.s.c. constructions. Thermodynamic and statistical mechanical theories give reasonable approximations to the observed Tg-MW curve but small systematic deviations are found. The effect of thermal history on Tg can be reproduced using a MW-dependent activation enthalpy.

Subject Keywords

Organic chemistry, Polymers and plastics

URI

https://hdl.handle.net/11511/51745

Journal

Polymer

DOI

https://doi.org/10.1016/0032-3861(89)90256-5

Collections

Department of Chemistry, Article

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Citation Formats

L. Aras and M. J. Richardson, “The glass transition behaviour and thermodynamic properties of amorphous polystyrene,” Polymer, pp. 2246–2252, 1989, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/51745.