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Updated: May 24, 2025

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Influence of topology on rheological properties of polymer ring melts
1Institute of Physics, Johannes Gutenberg University, Staudingerweg 9, 55128 Mainz, Germany.
Abstract:
We investigate with numerical simulations the influence of topology and stiffness on macroscopic rheological properties of polymer melts consisting of unknotted, knotted, or concatenated rings. While melts of flexible, knotted oligomer rings tend to be significantly more viscous than their unknotted counterparts, differences vanish in a low shear rate scenario with increasing degree of polymerization. Melts of catenanes consisting of two rings on the other hand are consistently more viscous than their unconcatenated counterparts. These topology-based differences in rheological properties can be exploited to segregate mixtures of otherwise chemically similar polymers, e.g., in microfluidic devices, which is demonstrated by exposing a blend of flexible knotted and unknotted oligomer rings to channel flow.
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