Researchers at UT created “Smart Plastic,” a material that is rigid in some areas and soft in others, that could potentially spearhead the future of soft robotics and wearable electronics. The team published their findings Oct. 13 in the journal Science.

There have been many attempts to create this material, said Zachariah Page, a corresponding author on the paper. By simply shining light and adding a catalyst, he said it is possible to control the stiffness and mechanical properties of the material.

“What makes it ‘smart’ is the fact that it has this extra layer of sophistication compared to traditional plastics,” assistant chemistry professor Page said. “We’ve combined two different properties into a single material, so it provides it with additional potential functionality.”

The stretchy property was largely inspired by living structures of organisms that are rigid in some areas and soft in others, a property that is optimal for wearable electronics, author Adrian Rylski said.

“We see this in nature all of the time, from turtle shells to sea shells,” graduate research assistant Rylski said. “They have these unique patterns and designs that let them have great mechanical properties.” 

Researchers started with a monomer, a small molecule that connects with other structures to create a polymer, Page said. 

“We can convert that single material into two different (properties) depending on whether we shine light on the system or we don’t,” Page said. “That gives us simple access to a scalable technology that provides the ability to control the material properties locally.”

Rylski said the preliminary research to obtain varied stiffness in plastic by combining different materials together resulted in a fragile material or increased complications.

“Anytime you start to bring two materials and blend them together, you’re likely compromising one aspect of the material,” Page said.

On the other hand, “Smart Plastic” is a multi-material structure, a single material that has different types of components embedded within it, Rylski said. 

Contrary to other plastics that require organic solvents detrimental to the environment, “Smart Plastic” requires almost none, Page said.

Page said the next step of the research is to translate “Smart Plastics” into three-dimensional spaces and access more complex geometries that mimic natural organisms.

“I would really like (Smart Plastic) to catalyze more research in this space of multi-materials and also (expand) beyond what is traditionally thought about,” Page said. “Thinking about multi-materials that way … will open up a lot of new avenues in science and engineering.”