Japanese researchers have unveiled a new type of glass that can heal itself from cracks and breaks.
The groundbreaking new material could lead to virtually unbreakable phone screens.
The breakthrough was discovered by accident by a Japanese graduate student who was trying to glue something.
The breakthrough could lead to an end to smashed screens – as the glass would simply be able to heal itself
The new polymer glass is ‘highly robust mechanically yet can readily be repaired by compression at fractured surfaces’, the team wrote in the journal Science.
Holding the fractured pieces together for just 30 seconds at 21 degrees celcius was enough to form a merged sheet capable of withstanding 300g in weight, the team found, and it returned to its original strength within a couple of hours, they found.
The properties of the polyether-thioureas glass were discovered by accident by graduate school student Yu Yanagisawa, who was preparing the material as a glue.
Yanagisawa told NHK that he didn’t believe the results at first and repeated his experiments multiple times to confirm the finding.
He said: ‘I hope the repairable glass becomes a new environment-friendly material that avoids the need to be thrown away if broken.’
‘High mechanical robustness and healing ability tend to be mutually exclusive,’ wrote the researchers.
‘Expanding the range of healable materials is an important challenge for sustainable societies.
‘Noncrystalline, high molecular weight polymers generally form mechanically robust materials, which, however, are difficult to repair once they are fractured.
‘This is because their polymer chains are heavily entangled and diffuse too sluggishly to unite fractured surfaces within reasonable timescales.
‘Here, we report that low molecular weight polymers, when cross-linked by dense hydrogen bonds, give mechanically robust yet readily repairable materials, despite their extremely slow diffusion dynamics.’
AN ACCIDENTAL DISCOVERY
The properties of the polyether-thioureas glass were discovered by accident by graduate school student Yu Yanagisawa, who was preparing the material as a glue.
Yanagisawa found that when the surface of the polymer was cut the edges would adhere to each other, healing to form a strong sheet after being manually compressed for 30 seconds at 21°C.
Further experimentation found that the healed material regained its original strength after a couple of hours.
Although other self healing materials have been made, they require ‘in most cases, heating to high temperatures, on the order of 120°C or more, to reorganise their cross-linked networks, is necessary for the fractured portions to repair,’ the team said.
The research, published in Science, by researchers led by Professor Takuzo Aida from the University of Tokyo,