High Strain Rate Behavior of Liquid Crystal Elastomers

Abstract

Liquid crystal elastomers are rubbery solids that couple liquid crystalline order and deformation. This coupling leads to properties that are attractive for a number of applications in soft robotics and energy absorption. This paper is motivated by the latter application, and provides a systematic experimental study of a particular class of liquid crystal elastomers -- the isotropic genesis polydomain liquid crystal elastomers -- over a wide range of strain rates. An important aspect of this study is a novel tensile drop-tower that enables tensile strain rates of 100 s$^{-1}$ that are important to application but previously inaccessible. The paper also extends a recently proposed constitutive model to the high strain rate regime, and shows that it can be fit to describe the observed behavior across the spectrum of examined behavior.