Phenomenological Theory of Isotropic-Genesis Nematic Elastomers

TL;DR

This paper develops a phenomenological model to understand how the elastomer network influences structure and fluctuations in isotropic-genesis nematic elastomers, revealing short-range oscillatory correlations due to network effects.

Contribution

It introduces a new phenomenological framework incorporating network compliance, nonlocal interactions, and a novel random field to explain nematic behavior in elastomers.

Findings

Prediction of short-range oscillatory spatial correlations in nematic alignment.

Identification of network-mediated nonlocal interactions affecting nematic structure.

Introduction of a random field reflecting memory of initial nematic order.

Abstract

We consider the impact of the elastomer network on the structure and fluctuations in the isotropic-genesis nematic elastomer, via a phenomenological model that underscores the role of network compliance. The model contains a network-mediated nonlocal interaction as well as a new kind of random field, which reflects the memory of the nematic order present at cross-linking, and also encodes local anisotropy due to localized polymers. Thus, we predict a regime of short-ranged oscillatory spatial correlations (both thermal and glassy) in the nematic alignment trapped into the network.