The glass transition behaviour and thermodynamic properties of amorphous polystyrene

Aras, Leyla
Richardson, Maxwell J.
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.


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Quantum mechanical calculations (QMC) and dissipative particle dynamics (DPD) siniulations were utilized to understand the nature of the short and long-range hydrogen bonding and its influence on the microphase morphology in segmented polyurethanes and segmented polyureas prepared without chain extenders through the stoichiometric reactions of hydroxy or amine terminated poly(tetramethylene oxide) (PTMO-1000) with 1,4-phenylene diisocyanate (PPDI) and 1,3-phenylene diisocyanate (MPDI). The possibility of lo...
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The synthesis of black conducting polymer (CP) and/or crosslinked polymers (CLP) and/or radical ion polymer (RIP) and/or white polymers (WP) and/or orange polymer (OP) were achieved by using KOH with TCP, pyrrole and thiophene via microwave energy in a very short time interval. Polymerizations were carried out by constant microwave energy with different time intervals varying from 1 to 25 min; or at constant time intervals with variation of microwave energy from 90 to 900 watt; or varying the water content ...
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The combined effects of solidification and viscous dissipation on the hydrodynamic and thermal behavior of polymer melt flow during the injection process in a straight plane channel of constant cross section are numerically studied by considering the shear-rate and temperature-dependent viscosity and transient-phase change behavior. A numerical finite volume method, in conjunction with a modified form of the Cross constitutive equation to account for shear rate, temperature-dependent viscosity changes and a...
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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: