Modeling elastic instabilities in nematic elastomers

TL;DR

This paper uses 3D elastodynamics simulations to study strain-induced stripe formation in nematic elastomers, revealing how mechanical deformation influences domain evolution and offering insights for device engineering.

Contribution

It introduces a finite element simulation approach to model and analyze the dynamic elastic instabilities in nematic elastomers, specifically stripe domain formation.

Findings

Stripe domains form with alternating director rotation during stretching.

The simulation captures the onset and evolution of stripe instabilities.

Provides a computational framework for designing nematic elastomer devices.

Abstract

Liquid crystal elastomers are cross-linked polymer networks covalently bonded with liquid crystal mesogens. In the nematic phase, due to strong coupling between mechanical strain and orientational order, these materials display strain-induced instabilities associated with formation and evolution of orientational domains. Using a 3-d finite element elastodynamics simulation, we investigate one such instability, the onset of stripe formation in a monodomain film stretched along an axis perpendicular to the nematic director. In our simulation we observe the formation of striped domains with alternating director rotation. This model allows us to explore the fundamental physics governing dynamic mechanical response of nematic elastomers and also provides a potentially useful computational tool for engineering device applications.