Thermal behavior of elastomers at high rates of tensile straining

The results of high strain-rate tensile straining of a variety of elastomers at a number of temperatures are reported. Temperature increases, ΔT, occurring within the sample were measured during the deformation; i.e., the technique of adiabatic stretching was applied. The use of well characterized rubbers of different tendencies to crystallize upon elongation gave information on the changes in molecular packing, of the contribution from entanglements to the effective crosslink density, and of the effect of chemical and structural factors on mechanical behavior during rapid extension. An analysis of the effect of frictional heating, of deformational energy conversion, and of the anticipated enthalpy of crystallization was performed. The experimentally obtained temperature increases, the magnitude of the above three main factors which contribute to ΔT, and the amount of strain-induced crystallization found are in agreement with theoretical considerations.