Fine structures and fracture processes in plastic‐rubber two‐phase polymer systems IV. Temperature and strain rate dependences of tensile properties

Yield stress (σ Y ) and elongation to break (ε b ) were measured over a wide range of temperature under three different strain rates ( {article}{empty}{document}ε{document} ) for a series of polyvinylchloride‐rubber blends, ABS polymer and high‐impact polystyrene. It was found that a temperature‐strain rate reduction was possible for σ Y and the composite curve obtained by the superposition was expressed by the following relation: where K 1 and K 2 are the material constants, and A T is the shift factor. As for ε b , a new maximum was found at around room temperature in addition to the known maximum at around the glass transition temperature of the matrix phase. The results are discussed in terms of the craze theory for rubber toughening of plastics.