Mechanisms of deformation in cross-linked polyethylene crystals

Abstract

Systematic electron diffraction and electron microscopy studies have been used to identify the mechanisms of deformation in cross-linked polyethylene single crystals. The crystals were cross-linked by exposing them to γ-rays. A marked difference between the operative deformation mechanisms in unirradiated and irradiated single crystals was observed, including the observation that stress-induced martensitio transformations are far more predominant in the cross-linked crystals. All of the observed differences in deformation behaviour have been explained satisfactorily in terms of the limited extensibility of cross-linked fold loops.