Uncovering phase fluctuations in oriented liquid crystal elastomer films

Project Description

Liquid crystal elastomers (LCE) are a class of stimuli-responsive polymers capable of programmable and reversible shape change. Low elastic modulus, comparable to muscle tissue, and biocompatibility make them of intense interest for biomedical applications such as implantable artificial muscles. These materials have two main phases, the low-temperature (ordered) nematic phase and the high-temperature (disordered) paranematic phase. By orienting the LCE precursor in a specific direction before crosslinking, the shape change of the material can be programmed. One such method is the surface enforced alignment of thin films using surface treated glass slides. Recent works indicate that the resulting films exhibit nanometer-scale phase fluctuations that diverge from the expected simple nematic orientation. For example, it has been observed that smectic regions of higher order can occur during crosslinking. These can dramatically affect the resulting material properties. Our study aims to resolve the evolution of such fluctuations through changes in the processing parameters and to correlate them with the material properties at the macroscale.

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