Accession Number : AD0465261

Title :   VOLUME DILATATION AND ENERGETIC STRESS IN RUBBERLIKE NETWORK POLYMERS.

Descriptive Note : Technical rept.,

Corporate Author : PRINCETON UNIV NJ FRICK CHEMICAL LAB

Personal Author(s) : Shen, Mitchel C. ; Tobolsky, Arthur V.

Report Date : JUN 1965

Pagination or Media Count : 13

Abstract : Current kinetic theories of rubber elasticity are usually derived on the assumption that the strain-induced volume dilatation can be ignored. While satisfactory in explaining the general stress-strain behavior of elastomers, the constant volume constraint must be removed when the theory is invoked to describe quantities that directly involve volume dilatation itself. It is shown that such modification can be accomplished within the present theoretical framework. The equation of state for rubber elasticity is presented. Based on the equation, the anisotropy factor of Elliott and Lippman was shown to be unity, as long as the strain limit imposed by the Gaussian statistics is not exceeded. Expressions for the strain-induced volume dilatation and the internal energy component of elastic force are derived. No approximations are introduced in arriving at these equations, which were previously thought to be approximate. Calculated theoretical curves are shown to compare favorably with existing experimental evidence in the literature. (Author)

Descriptors :   (*POLYMERS, ELASTIC PROPERTIES), (*ELASTIC PROPERTIES, THEORY), EQUATIONS OF STATE, ANISOTROPY, PARTIAL DIFFERENTIAL EQUATIONS, STRAIN(MECHANICS), STRESSES, ELASTOMERS.

Distribution Statement : APPROVED FOR PUBLIC RELEASE