Micromechanics of initiation of environmental craze growth in glassy polymers (in Czech) KOTOUL, M. vol. 34 (1996), no. 4, pp. 217 - 229
Abstract The present study aims to investigate theoretically the craze microstructure and its relation to the basic materials parameters such as the yield stress and the surface energy. Based on the assumption that the craze tip is somewhat blunted by small scale yielding and on the Taylor meniscus instability as the mechanism responsible for the propagation of the leading edge of the craze, the detailed micromechanical analysis is used to provide estimates of critical opening displacement of the craze for growth initiation, average fibril diameter and fibril volume fraction. All these parameters refer to the craze tip. Estimates derived from the theory are found to be fairly consistent with experimental observations for many polymers. The influence of a plasticizer on the yield stress and the surface energy is discussed together with predicted changes in the craze microstructure. Key words microstructure, surface energy, yield stress, micromechanical analysis, glassy polymers Full text not available
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