New smart material reacts to light, heals itself and remembers its shape

Researchers at WSU have for the first time developed a smart material with more than one function.
WSU researchers have created a material with multiple smart properties
WSU researchers have created a material with multiple smart properties

Smart materials are able to significantly alter one or more of their properties in response to external stimuli like heat, light or moisture. Scientists all over the world are developing smart materials for applications in product design, self-healing materials and programmable matter, among others. For instance, smart materials could change shape to unfold a solar panel on a space satellite without the need of a battery-powered mechanical device.

Research into the field has been held back because smart materials are difficult and expensive to produce and can usually only perform one function at a time. But, researchers at Washington State University (WSU) in the US have developed a unique, multifunctional smart material that can change shape from heat or light and assemble and disassemble itself.

The new material marks the first time that researchers have been able to combine several smart abilities, including shape memory behaviour, light-activated movement and self-healing behaviour, into one material.

The work, published in ACS Applied Materials & Interfaces, was led by WSU Professor Michael Kessler and Yuzhan Li, MME staff scientist, in collaboration with Orlando Rios, a researcher at Oak Ridge National Laboratory.

According to a press document released by WSU, the researchers used a class of long-chain molecules, called liquid crystalline networks (LCNs), which provide order in one direction and give material unique properties. The material changes in response to heat, inducing a shape-shifting behaviour. Groups of atoms were added to enable a reaction to polarised light and dynamic chemical bonds were used to improve the material’s ability to reprocess.

Through the additions, the researchers were able to create a material that can remember its shape as it folds and unfolds, heal itself when damaged and react to light. The material’s movements can be preprogrammed and its properties tailored.