Extensibility of Black Filled Elastomers

Abstract

Abstract Unique empirical relations are found to exist between the extension ratio at break λb and the crosslink density ν λb ∝ ν−0.75 in the absence of gross strain induced crystallization, and λb ∝ ν−0.2 in the presence of gross strain-induced crystallization. With black-filled elastomers, the modulus at 100% strain, M100, is proportional to the crosslink density over a wide temperature range. Thus, unique empirical relations exist between λb and M100 of black-filled elastomers; λb ∝ M100−0.75 in the absence of gross strain-induced crystallization, and λb ∝ M100−0.2 in the presence of gross strain-induced crystallization. The proportionality constants can be used as convenient measures of the extensibility in material evaluation on a constant modulus basis.