In entangled polymer melts and concentrated solutions, uncrossability of chains restricts the motions of a given chain transverse to its own path. Constraint release occurs when the end of a neighboring chain slips past a given chain, releasing it to hop transversely. We use molecular dynamics simulations of a melt of one long, self-entangled ring polymer to study constraint release. Monte Carlo moves are introduced to allow the ring to cross itself, as a proxy for constraint release. We detect changes in topological state of the ring and use isoconfigurational averaging to find the primitive path of the old and new configurations. The difference between the old and new primitive paths measures the effect of the constraint release. The perturbed region of primitive path spreads by Rouse dynamics. Most chain crossings involve only two primitive path segments, but occasionally three or more strands participate in a single event.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Inorganic Chemistry
- Materials Chemistry