As everyone who has painstakingly straightened their hair knows, water is the enemy. Hair carefully straightened by heat will bounce back into curls the minute it touches water. Why? Because hair has shape memory. Its material properties allow it to change shape in response to certain stimuli and return to its original shape in response to others.
What if other materials, especially textiles, had this type of shape memory? Imagine a T-shirt with cooling vents that opened when exposed to moisture and closed when dry, or one-size-fits-all clothing that stretches or shrinks to a person’s measurements.
Now, researchers at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) have developed a biocompatible material that can be 3D-printed into any shape and pre-programmed with reversible shape memory. The material is made using keratin, a fibrous protein found in hair, nails, and shells. The researchers extracted the keratin from leftover Agora wool used in textile manufacturing.
The research could help the effort to reduce waste in the fashion industry, one of the biggest polluters on the planet. Already, designers such as Stella McCarthy are reimagining how the industry uses materials, including wool. The material may also have medical uses.
“With this project, we have shown that not only can we recycle wool but we can build things out of the recycled wool that have never been imagined before,” said Kit Parker, the Tarr Family Professor of Bioengineering and Applied Physics at SEAS and senior author of the paper on the subject published in Nature Materials. “The implications for the sustainability of natural resources are clear. With recycled keratin protein, we can do just as much, or more, than what has been done by shearing animals to date and, in doing so, reduce the environmental impact of the textile and fashion industry.”