Effect of entanglement and crosslinking on the hyperelastic behavior of SBR rubber: A multiscale DPD simulation study

TL;DR

This study uses multiscale DPD simulations to analyze how entanglement and crosslinking influence the hyperelastic behavior of SBR rubber, revealing entanglement's significant contribution up to 50% in mechanical properties.

Contribution

It introduces a multiscale DPD modeling approach combining atomistic and coarse-grained methods to study rubber hyperelasticity, incorporating entanglement and crosslinking effects.

Findings

Entanglement contributes up to 50% to mechanical properties at strains up to 150%.

The multiscale model qualitatively and quantitatively matches experimental stress-strain data.

Crosslinking effects modeled by the Arruda-Boyce model improve understanding of rubber elasticity.

Abstract

In this study we have investigated into the entanglement effect and crosslinking effect in long-chain SBR rubber polymer system to model the mechanical hyperelastic behavior. The discussed methodologies are developed by a dissipative particle dynamics (DPD) based multiscale modeling method. The DPD interaction parameters are in turn obtained by all atomistic molecular dynamics and subsequently utilized by the DPD simulations. In the DPD simulation boxes, 200 long polymer chains and 1600 vulcanizing sulphur beads were packed. Vulcanization was achieved by random cross-linking among chains and entanglement was detected by utilizing the M-coil estimator. The mechanical effect of entanglement was modelled by extended tube model and the crosslinking effect was modelled by the Arruda-Boyce model. The modelled stress-strain curve is compared with the experimentally obtained curve for the qualitative and quantitative aspects of mechanical properties. It was determined that for strains up to 150%, the contribution of entanglement to the measured mechanical properties can be even up to 50%.