Predictors of cavitation in glassy polymers under tensile strain: a   coarse grained molecular dynamics investigation
  The nucleation of cavities in a homogenous polymer under tensile strain is investigated in a coarse-grained molecular dynamics simulation. In order to establish a causal relation between local microstructure and the onset of cavitation, a detailed analysis of some local properties is presented. In contrast to common assumptions, the nucleation of a cavity is neither correlated to a local loss of density nor, to the stress at the atomic scale and nor to the chain ends density in the undeformed state. Instead, a cavity in glassy polymers nucleates in regions that display a low bulk elastic modulus. This criterion allows one to predict the cavity position before the cavitation occurs. Even if the localization of a cavity is not directly predictable from the initial configuration, the elastically weak zones identified in the initial state emerge as favorite spots for cavity formation. 
Ali Makke (MATEIS), Michel Perez (MATEIS), Joerg Rottler, Olivier Lame   (MATEIS), Jean-Louis Barrat (LIPhy)
cond-mat.mtrl-sci