How stimuli-responsive materials can enable new technologies

Nature is full of examples of an organism or material responding to a stimulus, like a sunflower turning toward the sun. Harnessing this ability to change under different conditions could unlock many interesting and exciting applications for material systems.

A review by Mehta et al. examines the stimuli-responsiveness of liquid crystal polymers, which, when exposed to light, can transform into many interesting shapes with various topologies at different length scales. Since many new applications require intricate morphologies, understanding how liquid crystal polymers behave under optical stimuli, and the properties that result from those behaviors, could enable the development of next-generation technologies.

Author Patrick Onck says he hopes the review will allow scientists to move a step closer to achieving commercially usable technologies based on liquid crystal films, such as soft robots.

“The autonomous and decisive response characteristics demonstrated by photo-responsive liquid crystal films can pave the way to next-generation smart and intelligent systems,” Onck said. “However, despite all the technological advancements in the last decade, their commercial viability has still not been accomplished. This review aims to pave the way to move a step closer toward developing exciting new materials and devices for future applications.”

Author Ratna Kumar Annabattula says that while this review, which is based on work carried out in the past decade by research groups around the world, introduces readers to the stimuli-responsiveness of liquid crystals and their applications, future work should also investigate other properties of such systems, including their strength, durability and how they might be manufactured commercially.

Source: “Design and applications of light responsive liquid crystal polymer thin films: a review,” by Kanishk Mehta, Akhil Reddy Peeketi, Ling Liu, Dirk Broer, Patrick Onck, and Ratna Kumar Annabattula, Applied Physics Reviews (2020). The article can be accessed at https://doi.org/10.1063/5.0014619 .