A research group from South Korea has developed a smartphone display material that can self-repair from damage. The results of the work are published in the journal Composites Part B: Engineering.
Scientists from the Korea Institute of Science and Technology (KIST), led by Dr. Yun-Che Jung, head of the center at the Institute of Advanced Composite Materials, and Professor Hak-Su Han from Yonsei University, have developed a self-healing, colorless electronic material. It independently repairs cracks or damaged functions that have occurred on the material.
Colorless Polyimide (CPI) has outstanding mechanical, electrical, and chemical properties. It is transparent like glass and very durable: it does not get damaged even after hundreds of thousands of folds. CPI is widely commercialized and used in foldable and flexible displays and aerospace and photovoltaic applications.
Permanent experts try to make the polyimide even more durable by eliminating cracks that can occur in various exposure environments and breakdowns caused by continuous electromagnetic waves. Several research groups have tried to solve these problems by adding a protective layer to the surface.
To support rapid self-healing from cracks and damaged functions while retaining the benefits of colorless polyimide, the KIST-Yonsei University joint research team developed a self-healing colorless polyimide using linseed oil. It hardens easily at a room temperature of 25°C, so it is widely used as a coating material for preserving art objects.
The KIST research team made microcapsules filled with linseed oil that served as a healing layer mixed with silicone and polyimides. In the material developed by the team, the microcapsules break with mechanical damage, then linseed oil flows into the damaged area to harden, thereby “healing” it.
The self-healing, colorless polyimide can radically address the physical properties and durability of damaged polymeric materials, scientists are sure.