First-Principles Study of Bond Rupture of Entangled Polymer Chains

The entanglement of neighboring chains is a common topological defect found in polymers. The limiting stress and mechanism of rupture of two entangled polyethylene chains, subjected to external loading, has been investigated using first-principles molecular dynamics calculations. Our results show that intermolecular entanglement significantly weakens each polymer strand. Interchain bond−bond or atom−bond friction is the major driving force in the rupture process.