Control of material properties by light is an important technology. A photoresponsive columnar liquid crystal has been developed as a high-temperature resistant adhesive that melts by light, which is named “Light-Melt Adhesive”. This material displayed the performance with 1) a bonding strength of 1.6 MPa at room temperature and of 1.2 MPa even during heating at 100 °C, 2) photoinduced reduction of its bonding strength by 85%, and 3) instant photoseparation on the order of a few seconds using a common UV-LED (total 320 mJ cm-2 dose). Furthermore, this material showed value-added properties: 4) reusability by heat iniialization over 160 °C , and 5) visualization of the bonding/nonbonding phases by fluorescence change. The light-melt adhesive will accelerate the on-demand photoseparation technology in various manufacturing processes.
Research Area “Molecular technology and creation of new functions”
Research Theme “Transformation of pi-electron systems as a molecular technology for the creation of new functional materials”
Shohei Saito, Shunpei Nobusue, Eri Tsuzaka, Chunxue Yuan, Chigusa Mori, Mitsuo Hara, Takahiro Seki, Cristopher Camacho, Stephan Irle, and Shigehiro Yamaguchi. “Light-melt adhesive based on dynamic carbon frameworks in a columnar liquid-crystal phase”. Nature Communications, Published online 04 July 2016, doi: 10.1038/ncomms12094.
Shohei Saito, Ph.D.
Associate Professor, Department of Chemistry, Graduate School of Science, Kyoto Universit
Sofia Saori Suzuki, Ph.D.
Manager, Green Innovation Group, Department of Innovation Research, JST