The role of compliant-particle size in toughening glassy polymers

6 The role of compliant-particle size in toughening glassy polymers 

The effect of particle size on the toughening of polymers has been studied by a number of investigators. Some of the more prominent explanations have been reviewed by Piorkowska et al. (1990). There is general agreement that compliant particles of less than a critical size are ineffective in craze initiation (Bucknall 1977 Kramer 1983), but that size alone is not a deciding factor and that particle morphology and stiffness, as well as the level of the applied stress, are also important. 

Although some localized craze initiation can also occur from particles that are stiffer than their surroundings (Wang et al. 1971), the particles with the most 

This immediately establishes the critical particle diameter Dc below which under an applied stress crazes cannot form. This critical particle diameter is 

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