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There are polymers that keep altering their shapes, responding to differences in temperature. A team of researchers from the University of Rochester has now built up a material that alters in response only to body heat. It offers a number of new opportunities in medical and other applications, including artificial skin, sutures, and self-fitting clothing, according to HNGN.

Hence, a kind of shape-memory polymer that can take on the form of a temporary shape till it is powered to return to its original form has been created. A particular trigger, such as heat, can "fine-tune" the material.

"Tuning the trigger temperature is only one part of the story," Mitch Anthamatten, who led the research team, said in a press release. "We also engineered these materials to store a large amount of elastic energy, enabling them to perform more mechanical work during their shape recovery."

The deformation is marked by polymer chains getting stretched and crystallites, or small segments of polymers getting aligned in the same area. These fix the material into temporary shapes. With the rise in crystallite numbers, the shape of the polymer gets more rigid and tougher to revert to the original state.

The crystallization process occurring during the cooling and stretching of the materials was created. Anthamatten and his team added molecular linkers to every polymer strand, limiting crystallization during stretching. After changing the number and types of links in the polymer, the team could adjust its stability and set its melting point to near 35 degrees Celsius---on the borderline of the body's temperature.

"Our shape-memory polymer is like a rubber band that can lock itself into a new shape when stretched," said Anthamatten. "But a simple touch causes it to recoil back to its original shape."

The study was published in the Jan.13,2016 issue of the Journal of Polymer Science.