Phys.org July 26, 2018
A team of researchers in the US (University of Colorado, Boulder, NIST) designed two new polymers, one which starts as a solid and can be converted into liquid, and the other which starts as a liquid and can be converted into a solid. The solid and liquid polymers both switch phase when irradiated by UV light with a 365-nm wavelength for about five minutes. However, the light affects the two materials differently. Using light instead of temperature or pressure to control the phase changes makes it possible to exert exquisite spatial control over these phase changes, allowing the researchers to define separate solid and liquid regions in a single material. This material effectively bridges the gap between thermoplastics and thermosets at very low operating temperatures, allowing for recycling, repurposing or remolding and on-demand application to a substrate… read more. Open Access TECHNICAL ARTICLE
By using light to switch the phase of the new photoswitchable materials, the researchers could spatially control the solid and liquid regions in a single material. Credit: Worrell et al. Published in Nature Communications