Accession Number : AD0604549

Title :   THERMODYNAMIC PROPERTIES OF NATURAL RUBBER AND ISOPRENE,

Corporate Author : NAVAL ORDNANCE LAB WHITE OAK MD

Personal Author(s) : Warfield,R. W. ; Petree,M. C.

Report Date : 18 JUN 1964

Pagination or Media Count : 21

Abstract : Using published specific heat data, the entropy, enthalpy, and Gibbs free energy of natural rubber (NR) was calculated over the temperature range 0 to 320K. These functions were also calculated for isoprene over the temperature range 0 to 300K. At 298.16K the entropy of polymerization was found to be 24.00 cal/mole deg. and the free energy of polymerization 10.7 Kcal/mole. The thermodynamic function Cp/T versus T calculated for NB exhibits a maximum at 50K and another maximum at 210K which is associated with the glass transition. The number of classically vibrating units per repeating unit of NR is 6.61 at 300K. (Author)

Descriptors :   (*RUBBER, THERMODYNAMICS), (*ISOPRENE, THERMODYNAMICS), POLYMERS, THERMAL PROPERTIES, SPECIFIC HEAT, ENTROPY, ENTHALPY, POLYMERIZATION, TRANSITION TEMPERATURE, MOLECULAR PROPERTIES

Distribution Statement : APPROVED FOR PUBLIC RELEASE