Molecular Weight Effects on Craze Fibril Breakdown

1 Molecular Weight Effects on Craze Fibril Breakdown 

While the size effect is very important in craze breakdown and fracture and necessitates the use of the full Weibull analysis in making comparisons between samples of different size, the median plastic strain for fibril breakdown — e is a useful relative indicator of the breakdown resistance of crazes in different polymer 

Similar behavior has been found for dust-free films of poly(methylmethacrylate) (PMMA) and poly(a-methylstyrene) (PaMS) as shown in Figs. 35b and 35c and we expect similar results for any glassy polymer that deforms predominantly by crazing at low temperatures (i.e., one in which scission-dominated crazing occurs in preference to shear deformation). 

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