Analysis of temperature effects near mode I cracks in glassy polymers

A previous isothermal study (Estevez et al., Journal of Mechanics and Physics of Solids 48, 2585-2617, 2000) has shown that the toughness of glassy polymers is governed by the competition between shear yielding and crazing. The present work aims at investigating loading rates for which thermal effects need to be accounted for. The influence of the heat coming from the viscoplastic shear yielding and from crazing on their competition and on the toughness is examined. Crazing is shown to be the dominant heat source, and the dependence of the craze properties on temperature appears to be key in controlling the toughness of the material.