Phase Transitions in Liquid Crystalline Elastomers: A Fundamental Aspect of LCEs as Artificial Muscles

Abstract

Liquid crystalline elastomers (LCEs) are composed of low molecular weight mesogenic units tethered to a cross-linked polymer network. Because LCEs have remarkable shape-changing properties at the nematicisotropic phase transition, it has been suggested that they could serve as generic large amplitude, low frequency actuators and sensors i.e. artificial muscles. As this transition does not exist in LCEs when the mesogenic side chains are uniformly oriented, the understanding of phase transitions in LCEs emerges as a topic of fundamental interest for their application as artificial muscles.