Distribution of tensile data of vulcanized rubbers. I. Tensile data of SBR vulcanizates loaded with light calcium carbonate

Abstract

AbstractWhen the first asymptotic probability function of smallest values was applied to analyze the distribution of tensile strength data for rubbers, good agreement between observed values and theory did not always result. In order to improve the agreement, use of another distribution function, the third asymptotic probability function, was proposed. Experiments verified that this function yielded good agreement with theory for the distribution of tensile strengths of rubbers, especially for SBR vulcanizates loaded with light calcium carbonate. The third asymptotic probability function contains three parameters: the characteristic value V, the lower limit ε, and the shape parameter k which is dimensionless. Analysis is made by use of a logarithmic extremal probability paper on which the probability function plots as a straight line if ε = 0. There appears to be a lower limit for the distribution of tensile strengths but not for the distribution of elongations. This suggests that the tensile properties follow the third asymptotic distribution function, with the breaking elongations following the simplified form of the Weibull distribution.