# Robust and Multi-Functional Electrically Responsive Gold/Polydopamine-Coated Liquid Crystalline Elastomer Artificial Muscles

## TL;DR

This paper introduces a method to improve the performance of artificial muscles by enhancing the adhesion of electrically conductive coatings on liquid crystalline elastomers.

## Contribution

A new method using polydopamine treatment to enhance adhesion of gold coatings on LCEs, enabling multi-functional electrically responsive artificial muscles.

## Key findings

- PDA treatment significantly improves adhesion of gold coatings on LCEs.
- The method enables fabrication of LCEs with strain-sensing and electro-responsive features.
- The resulting materials exhibit self-actuation-sensing and joule-heating capabilities.

## Abstract

Applying thin electrically conductive coatings to Liquid Crystalline Elastomers (LCEs) is an effective way of functionalizing two-way shape memory polymers with the ability to respond to electrical currents. However, achieving robust adhesion between a given electrically conductive coating and the surface of LCEs can be challenging. This can limit the functionality, performance, and potential applications of these materials. This work describes a facile method to develop electrically responsive Liquid Crystalline Elastomer polymeric artificial muscles with strain-sensing, self-actuation-sensing, and joule-heating features. In this work, the effect of treating LCEs with polydopamine (PDA) prior to functionalizing the LCE with an electrically conductive gold-sputtered coating was explored. The findings confirmed that the PDA treatment considerably improved the adhesion of the gold sputter coating to the LCEs, thereby leading to the fabrication of multi-functional strain-sensing, electrically conductive, and electro-responsive LCEs.