Novel Polymer Network lets Materials Heal Faster

Researchers have developed a new cross-linking reaction that can advance self-healing polymers.

Scientists at the Karlsruhe Institute of Technology and Evonik Industries demonstrated that the cross-linking reaction can lead to self-healing materials repair damage under mild temperatures.

According to the researchers, switchable networks in self-healing plastic can be decomposed and reassembled again.

"Our method does not need any catalyst, no additive is required," Professor Christopher Barner-Kowollik, one of the study researchers, said.

The new polymer network can heal itself within minutes at relatively low temperatures from 50°C to 120°C. KIT researchers developed a healing cycle to synthesize a large number of intermolecular compounds that start closing during cooling. The team conducted several tests including tensile and viscosity tests and found that the material had its initial mechanical properties intact.

The reaction used in the research is called a Diels-Alder reaction. Their work is described in the journal Advanced Materials.

"We succeeded in demonstrating that test specimens after first healing were bound even more strongly than before," Barner-Kowollik said in a news release.

The latest technique not only promises newer self-healing materials that can repair themselves repeatedly, but also shows that it is possible to transfer a new mechanical property to polymers. According to researchers, the new reaction enhances plastics' flowability. These plastics can be used in aircrafts and cars.

Self-healing material science has recently seen some major advancement.

University of Illinois researchers reported earlier this year that they have made self-healing polymers using commercially available products. Other scientists from Spain have materials that don't need any external trigger to start repairing itself.

Self-healing materials reached a whole new level when Massachusetts Institute of Technology scientists created a material using E.coli bacteria. The new material has properties of both living and non living things.