Computational Evaluation of Micro- to Macroscopic Deformation Behavior of Amorphous Polymer with Slightly Heterogeneous Distribution of Initial Shear Strength

Abstract

We investigate the characteristic deformation behavior of an amorphous polymer with a heterogeneous distribution of the initial shear strength (ISS). The deformation behavior of polymers under macroscopically uniform tension, and of plane strain polymer unit cell with a cylindrical void under combined straining were investigated by computational simulation with the nonaffine molecular chain network model. The results revealed the onset, evolution and interaction of microscopic shear bands emanating from slightly weak points, and the percolation of new shear bands. The micro- to macroscopic isotropy of the deformation response has been verified. Although the existence of distribution of ISS substantially affects the deformation, the effects of distribution patterns and standard deviation of ISS on the deformation were small. The interaction between the heterogeneity of ISS and voids substantially affects such micro- to macroscopic deformation behavior as onset and propagation of shear bands, mean stress distribution, and macroscopic stress vs strain relationship.