Effect of Heterogeneity of Microstructure of Amorphous Polymer on Micro- to Macroscopic Deformation Behavior

Abstract

The purpose of the present study is to elucidate the micro-to macroscopic deformation behavior of an amorphous polymer with slightly heterogeneous distribution of molecular chain, in other words, the distribution of the initial strength of the polymer. The micro-to macroscopic deformation behavior of polymer blocks under macroscopically uniform tension, compression and shearing, and surface deformation of the plane strain block under compression were investigated by means of computational simulation with the nonaffine molecular chain network model. The results clarified the onset of microscopic shear bands emanating from the slightly weak points and their evolution, interaction and percolation of new shear band. The effect of distribution patterns and variation of initial shear strength on the deformation, the interaction of weak points, transition of microscopic shear bands to macroscopically inhomogeneous deformation including the evolution of surface undulation under compression have been demonstrated. In macroscopically homogeneous deformation as well as heterogeneous deformation, the deformation resistance increases with the introduction of heterogeneity of the initial shear strength.