Network Polydispersity and Deformation-Induced Damage in Filled Elastomers

An a priori assumption in micromechanical analysis of polymeric networks is that the constitutive polymer strands are of equal length. Monodisperse distribution of strands, however, is merely a simplifying assumption. This paper relaxes this assumption and considers a vulcanized network with a broad distribution of strand length. In the light of this model, this study predicts the damage initiation and stress-stretch dependency in filled polymer networks with random internal structures. The degradation of network mechanical behavior is assumed to be controlled by the adhesive failure of the strands adsorbed to the filler surface. This study shows that the short adsorbed strands are the culprits for damage initiation and their finite extensibility is a key determinant of the mechanical strength.