ABSTRACT
Analysis of modern concepts concerning the mechanism of fracture in solid polymers was presented in Chapter 1. This analysis shows that real strength of polymers is controlled not only by the strength of chemical bonds broken upon fracture but also by the defects and heterogeneous structure of polymers. Specific structures of solid polymers are known to control the development of fracture sites under applied stress. Taking into account the fact that the smallsized samples (fibers, films) contain no rough defects [48], the kinetics of the nucleation of fracture sites (hence, strength and lifetime) is primarily governed by a set of defects (flaws) produced in polymer upon its processing. In turn, a possible set of structural defects in polymer is specified by hierarchy of discrete structures which is typical of polymer fibers and films [112]. Below, the analysis of structure and defects of some amorphous and semicrystalline polymers is presented.
