CAREER: Experimental and Theoretical Studies of Mechanics Interacting with Electric/Optical Fields in Liquid Crystal Elastomers

University Of California-San Diego, La Jolla CA

Investigators

Abstract

This Faculty Early Career Development (CAREER) project will investigate coupling phenomena in liquid crystal elastomers, a combination of liquid crystal molecules and polymer networks. Liquid crystal elastomers have many special properties which have led to diverse applications ranging from artificial muscles to stretchable optical devices. Because of the complex molecular structure, many phenomena observed in liquid crystal elastomers are still elusive and the unique properties of liquid crystal elastomers have not been fully explored. This research will develop an innovative and robust technique to fabricate liquid crystal elastomers with desired properties. The PI will also formulate a mechanics theory of liquid crystal elastomers with large deformations that may be triggered by various external stimuli. The results from the project will promote further development of liquid crystal elastomers for a wide range of applications, such as responsive elements used in soft robotics, active materials used in energy harvesting/conversion systems and soft materials used in various actuators or sensors. Moreover, the impact of the project will be broadened via the integrated education and outreach programs including course development, a mini summer camp and outreach to high school students. The research objective of this multidisciplinary project is to investigate multi-field coupling phenomena in liquid crystal elastomers, using a using a combined theoretical, computational, and experimental approach. We will develop a strain-engineering technique to apply predesigned inhomogeneous strain fields onto a lightly-crosslinked liquid crystal elastomer film during its second-step crosslinking reaction so as to obtain patterned molecular orientations in the material. Combining experiments and theoretical studies, we will further explore the interplay between mechanics and electrical/optical field in liquid crystal elastomers with the target of realizing diverse voltage or light-induced deformation modes in the material. As a result, this research project will result in a better understanding of the behaviors of liquid crystal elastomers, provide mechanistic insights into the dynamic behaviors of biological materials with similar molecular structures and promote new engineering applications of the special material.