Hyperelastic gel is one of the stretchiest materials known to science

A hydrogel that may stretch to round 15 instances its preliminary size is likely one of the most elastic supplies but recognized and might be used for robotic grippers or tendons.

Hydrogels, that are product of lengthy chain-like polymer molecules linked by water molecules, are well-known for his or her stretchiness, however they usually don’t return to their authentic form when they’re stretched an excessive amount of.

Lili Chen at Tsinghua College in Beijing and her colleagues have developed a brand new sort of hydrogel that’s terribly stretchy however maintains its authentic form. They modified the standard hydrogel construction by inserting what they name pearl-necklace chains, which include coiled polymer beads linked by a series of carbon atoms. These can unfurl beneath pressure and rewind when the pressure is launched.

To make these chains, Chen and her group dried out a hydrogel in order that the polymer chains had been drawn to themselves, when usually they’d be pulled extra strongly by the water molecules.

They discovered {that a} 30-centimetre size of their hydrogel might stretch to almost 5 metres earlier than returning to its authentic size in a number of seconds. A 2-centimetre-wide disc of the hydrogel, pulled outwards in all instructions, might improve 100 instances in space earlier than returning to its authentic dimension.

The researchers additionally constructed inflatable robotic grippers from the hydrogel, designed to softly deal with fragile issues. These had been in a position to choose up objects equivalent to strawberries and had been extraordinarily harm resistant, persevering with to work after an individual stood on them or pierced them with a needle.

“Hydrogels are normally stretchy however not that elastic, whereas this gel combines each properties to make ultra-deformable and hyper-elastic supplies.” says Zehuan Huang at Peking College in China, who wasn’t concerned within the research. “Undoubtedly, this work represents a serious breakthrough in high-performance polymeric supplies, and can encourage substantial curiosity into exploitation of hyper-elastic gels in mushy robotics.”