THERMODYNAMIC PROPERTIES OF POLYSTYRENE AND STYRENE

Abstract

A Tarassov function has been used to estimate the specific heat of polystyrene between 0 and 60 K and these data, together with published Cp data, have been used to calculate the entropy, enthalpy, and free energy of styrene and polystyrene from 0 to 298.16 K. Entropy of polymerization of styrene at 298.16 K was found to be 26.69 cal/deg. mole. Changes in the various thermodynamic functions at the glass transition temperature, Tg, are in accordance with the second order transition as defined by Ehrenfest. The thermodynamic function Cp/T vs T as calculated for polystyrene increases to a maximum at 65 K and then increases agin at the glass transition temperature. An approximation is made of the heat capacity at constant pressure per vibrating unit of polystyrene at 273 K. Cp-Cv is calculated at 273 K and found to be 0.019 cal/deg. gm. or 1.98 cal/deg. mole. (Author)

Document Details

Document Type
Technical Report
Publication Date
Feb 01, 1961
Accession Number
AD0252578

Entities

People

  • M.c. Petree
  • R.w. Warfield

Organizations

  • Naval Ordnance Laboratory

Tags

DTIC Thesaurus Topics

  • Dielectric Polymers
  • Enthalpy
  • Free Energy
  • Glass
  • Glass Transition Temperature
  • Heat Capacity
  • Polystyrenes
  • Specific Heat
  • Styrenes
  • Thermodynamic Properties
  • Transition Temperature
  • Transitions

Fields of Study

  • Materials science

Readers

  • Combustion science or combustion engineering.
  • Polymer Science and Technology