Research Projects

Liquid crystal elastomers (LCEs) with well-defined liquid crystal (LC) alignment can undergo programmable, reversible, fast and large deformation in response to environmental cues. This makes them a promising material for diverse applications in actuators, soft robots, organ-on-a-chip and biomedical devices. The rapid advances in LC alignment strategies and LC chemistry have enabled development of LCEs that exhibit a wide range of complex actuation behavior, not seen in isotropic elastomers. However, LCEs are characterized by lack of biochemical features such as adhesion and encapsulation/permeability to chemical/biological species. Consequently, these LCEs cannot chemically interact with their surroundings in ways biological organisms do. This is particularly critical in the context of developing soft robots that can move/respond to and eliminate/modify localized stimulation events – functionalities that are highly desirable in biomedical applications. Furthermore, while LCEs are typically fabricated as thin films, spheroid microbots are often needed as their geometry allows combining long-distance locomotion and surface anchoring with actuation. It is not yet known how to design these microbots in ways that enable interaction with the environment. To this end, the proposed research will focus on the fabrication and evaluation of LCE-hydrogel based Janus actuators and microbots. These advanced biomimetic materials will integrate features of a hydrogel-based carrier, to interact with the environment, while retaining the unique sensing and actuation properties of LCEs. Three research areas are proposed 1.First focus will be on the fabrication of stimuli-responsive bimorph LCE-hydrogel actuators with strong LCE-hydrogel attachment. The goal would be to understand the role of LC alignment and LCE-hydrogel interfacial toughness on actuation properties (shape-morphing, crawling, bending) under directed and patterned physical stimuli in both dry and wet environments 2.Next phase will go beyond bimorphs to develop & characterize stimuli-responsive LCE-hydrogel actuators with geometries offering features such as (i) anchored actuation (ii) LCE actuation-triggered hydrogel activation and (iii) combining propulsion with actuation 3.Finally, bio-inspired applications focused on targeted & autonomous delivery, and remote-control of micro-reactions will be showcased. The underlying theme of these applications will be the programmed release of encapsulates from hydrogel following LCE actuation or after the device has travelled or anchored to a specified target. Overall, the proposed research aims to initiate the development of a new class of LCE-based smart material by addressing fundamental questions related to the fabrication, characterization and actuation of hybrid LCE-hydrogel devices. Such multi-functional devices hold significant potential for use in next generation of soft robotics, wearable sensors, on-demand therapeutics and interactive technologies