Damage of Cross-Linked Rubbers as the Scission of Polymer Chains: Modeling and Tensile Experiments

TL;DR

This paper presents a damage model for cross-linked rubbers based on polymer chain scission, integrating molecular-level damage with macroscopic elastic behavior, validated through tensile experiments.

Contribution

It introduces a novel damage model linking molecular chain scission to macroscopic rubber failure, enabling prediction of damage evolution and failure.

Findings

Model accurately predicts rubber failure under tensile loading.

Scaling laws relate molecular parameters to damage progression.

Experimental validation confirms the model's effectiveness.

Abstract

This paper develops a damage model for unfilled cross-linked rubbers based on the concept of scission of polymer chains. The model is built up on the well-known Gent elastic potential complemented by a kinetic equation describing effects of polymer chain scission. The macroscopic parameters in the damage model are evaluated through the parameters for undamaged elastomer. Qualitative analysis of changing molecular parameters of rubbers under scission of polymer chains resulted in easy scaling modeling the dependences of these parameters on the damage factor. It makes possible to predict the rubber failure in molecular terms as mechanical de-vulcanization. The model was tested in tensile quasi-static experiments with both the monotonous loading and repeated loading-unloading.