A recent scientific breakthrough could see self-healing polymers – which are able to “heal” like human skin – become viable for manufacture in existing factories in six to 12 months.
Once viable on a commercial scale, self-healing materials could extend the lifespan of relatively inexpensive commodities, such as paints, plastics and coatings. This would ultimately reduce waste because these items wouldn’t need to be replaced or repaired as often.
Research in self-healing materials is not new. A range of materials have already been engineered in labs with self-healing properties, including building materials such as concrete and water-resistant coatings.
But a team led by Marek Urban, the JE Sirrine Foundation Chair and professor at the Department of Materials Science and Engineering at Clemson University, have discovered a way to produce self-healing polymers on existing production lines.
“For anybody who wants to make these types of self-healing materials, they would have to essentially design a synthetic process and scale it up,” Dr Urban said.
“The key is that the scale-up process would have to be precisely controlled. There is a huge difference between making something in the lab and scaling it up. We know the technology is available for them.”
Dr Urban said that until this breakthrough, it’s been unclear exactly why the polymers are capable of self-healing.
“The difference with our team is that we know exactly how to design these systems. We understand the limitations, we have analytical tools to measure, and we understand what it takes for this technology to go to the next level,” Dr Urban said.
How do self-healing polymers work?
Normal plastics are made by sticking long molecular chains called polymers together. But natural intermolecular forces make Dr Urban’s polymers difficult to pull apart. This “lock and key” mechanism, known as van der Waals forces, also brings polymers back together again if damaged.
“So, when you pull them out, they come back together. It becomes self-healable at that point,” he said.
“These studies also revealed that ubiquitous and typically weak van der Waals interactions in plastics, when oriented, will result in self-healing.
“This discovery will impact the development of sustainable materials using weak bonding which becomes collectively very strong when oriented.”
Research on these materials has typically been inspired by self-healing processes found in nature, such as blood clotting in mammals.