Effects of topological constraints on linked ring polymers in solvents of varying quality

Author(s)
Zahra Ahmadian Dehaghani, Iurii Chubak, Christos N. Likos, Mohammad Reza Ejtehadi
Abstract

We investigate the effects of topological constraints in catenanes composed of interlinked ring polymers on their size in a good solvent as well as on the location of their θ-point when the solvent quality is worsened. We mainly focus on poly[n]catenanes consisting of n ring polymers each of length m interlocked in a linear fashion. Using molecular dynamics simulations, we study the scaling of the poly[n]catenane's radius of gyration in a good solvent, assuming in general that Rg ∼ mμnν and we find that μ = 0.65 ± 0.02 and ν = 0.60 ± 0.01 for the range of n and m considered. These findings are further rationalized with the help of a mean-field Flory-like theory yielding the values of μ = 16/25 and ν = 3/5, consistent with the numerical results. We show that individual rings within catenanes feature a surplus swelling due to the presence of NL topological links. Furthermore, we consider poly[n]catenanes in solvents of varying quality and we demonstrate that the presence of topological links leads to an increase of its θ-temperature in comparison to isolated linear and ring chains with the following ordering: Tθcatenane > Tθlinear > Tθring. Finally, we show that the presence of links similarly raises the θ-temperature of a single linked ring in comparison to an unlinked one, bringing its θ-temperature close to the one of a poly[n]catenane.

Organisation(s)
Computational and Soft Matter Physics
External organisation(s)
Sharif University of Technology Tehran, Institute for Research in Fundamental Sciences (IPM)
Journal
Soft Matter
Volume
16
Pages
3029-3038
No. of pages
10
ISSN
1744-683X
DOI
https://doi.org/10.1039/C9SM02374G
Publication date
03-2020
Peer reviewed
Yes
Austrian Fields of Science 2012
103023 Polymer physics, 103029 Statistical physics
Keywords
ASJC Scopus subject areas
Condensed Matter Physics, General Chemistry
Portal url
https://ucrisportal.univie.ac.at/en/publications/ca2dd474-4fc1-4adf-83eb-96dd574a776e