Effects of Topological Constraints on Penetration Structures of Semi-Flexible Ring Polymers.

ABSTRACT: The effects of topological constraints on penetration structures of semi-flexible ring polymers in a melt are investigated using molecular dynamics simulations, considering simultaneously the effects of the chain stiffness. Three topology types of rings are considered: 0₁-knot (the unknotted), 3₁-knot and 6₁-knot ring polymers, respectively. With the improved algorithm to detect and quantify the inter-ring penetration (or inter-ring threading), the degree of ring threading does not increase monotonously with the chain stiffness, existing a peak value at the intermediate stiffness. It indicates that rings interpenetrate most at intermediate stiffness where there is a balance between coil expansion (favoring penetrations) and stiffness (inhibiting penetrations). Meanwhile, the inter-ring penetration would be suppressed with the knot complexity of the rings. The analysis of effective potential between the rings provides a better understanding for this non-monotonous behavior in inter-ring penetration.

SUBMITTER: Guo F 

PROVIDER: S-EPMC7696204 | biostudies-literature | 2020 Nov

REPOSITORIES: biostudies-literature