Paper Number
SM34
Session
Polymers Solutions, Melts and Blends
Title
Rheology of linear polymer melts with end-on and side-on liquid crystal moieties in different phases: Effects of composition and thermodynamical state on relaxation dynamics
Presentation Date and Time
October 11, 2022 (Tuesday) 5:25
Track / Room
Track 2 / Sheraton 3
Authors
- Becerra, Diego (Ohio State University, Chemical and Biomolecular Engineering)
- Hall, Lisa M. (Ohio State University, Chemical and Biomolecular Engineering)
Author and Affiliation Lines
Diego Becerra and Lisa M. Hall
Chemical and Biomolecular Engineering, Ohio State University, Columbus, OH
Speaker / Presenter
Becerra, Diego
Keywords
computational methods; polymer melts
Text of Abstract
Liquid crystals (LCs) are self-organizing molecules that can be attached to linear polymer chains either within the backbone or in an end-on or side-on configuration along the backbone. Polymers with two different types of LC moieties can be designed to exhibit complex deformation behavior in response to heat. Here, the need to understand the structural transitions and the rheology of these materials is particularly relevant. We conduct coarse-grained molecular dynamics simulations of a melt of linear polymer chains with purely end-on groups, purely side-on LC groups, and different compositions of LC types along the chain. At high enough temperatures, entropic effects dominate, and the polymer chains approach a random walk configuration. In contrast, at lower temperatures, the LC groups can form ordered phases. In this context, we analyze from a molecular perspective both the role of liquid-crystalline order and polymer backbone conformation in the viscoelastic properties of liquid crystalline polymer melts and how the relaxation dynamics of these systems is affected by the different temperature-dependent phases. This work provides insights into the underlying physics of complex side-chain liquid crystalline polymer systems.