A new type of glass that can repair cracks by itself has been developed by researchers in Japan.
The glass, made from polyether-thioureas – a low-weight polymer – can repair breaks when it is pressed together by hand. This is the first time a hard substance has been discovered to be repairable without requiring high heat to melt the material.
Led by Professor Takuzo Aida, from the University of Tokyo, the researchers said their findings could result in self-repairing glass being used in smartphone screens, among other uses. This, they explained, is important in trying to drive more sustainability within societies.
Writing in the journal Science, the scientists said that “high mechanical robustness and healing ability tend to be mutually exclusive”.
They added that although other self-repairing materials have been developed, “in most cases, heating to high temperatures, on the order of 120 degrees Celsius or more, to reorganise their cross-linked networks, is necessary for the fractured portions to repair”.
According to the research, the new type of glass is both “highly robust mechanically” and can “readily be repaired by compression at fractured surfaces”.
The polyether-thioureas glass’ ability to repair itself was discovered accidentally by graduate student Yu Yanagisawa, who was preparing the material for use as glue. He found that when the polymer’s surface was cut, the edges would adhere to one another. They would then heal, forming a strong sheet after being compressed manually for just 30 seconds at 21 degrees.