Conformation and topology of cyclical star polymers

TL;DR

This study investigates the conformational and topological properties of cyclical star polymers, revealing that linking between arms significantly affects their structure and size, with implications for understanding complex polymer topologies.

Contribution

It provides a comparative analysis of unlinked and linked cyclical star polymers, highlighting how linking alters their conformation and internal structure.

Findings

Unlinked cyclical star polymers behave similarly to linear star polymers with doubled arms.

Linking reduces the gyration radius regardless of the linking protocol.

High linking degree causes qualitative changes in the internal density distribution.

Abstract

We study the conformation and topological properties of cyclical star polymers with $f$ ring arms, each made of $n$ beads. We find that the conformational properties of unlinked cyclical star polymers are compatible to those of linear star polymers with $2f$ arms made of $n/2$ beads each. This compatibility vanishes when the topology of the star, measured as the degree of linking between arms, changes. In fact, when links are allowed we notice that the gyration radius decreases as a function of the absolute linking number $\vert Lk \vert$ of the arms, regardless of the protocol that is employed to introduce said links. Furthermore, the internal structure of the macromolecules, as highlighted by the radial density function, changes qualitatively for large values of $\vert Lk \vert$.