Toughness of oriented polymers

This review article supported by some original photographs and model diagrams summarizes the mechanisms of toughness in oriented semicrystalline polymeric materials. In particular, crack propagation mechanisms in rubber-modified and oriented polymeric systems are compared. The Cook-Gordon mechanism of crack blunting in anisotropic materials can explain the low-temperature impact resistance of oriented semicrystalline polymers, fracture behaviour of biological composite structures and also the effects of photo-oxidative degradation on mechanical behaviour of oriented films.