title: Photoregulated Living Supramolecular Polymerization Established by Combining Energy Landscapes of Photoisomerization and Nucleation-Elongation Processes.
abstract: The significant contribution of conventional living polymerization to polymer science assures that living supramolecular polymerization will also lead to a variety of novel phenomena and applications. However, the monomer scope still remains limited in terms of the self-assembly energy landscape; a kinetic trap that retards spontaneous nucleation has to be coupled with a supramolecular polymerization pathway, which is challenging to achieve by molecular design. Herein, we report a rational approach to addressing this issue. We combined the supramolecular polymerization and photoisomerization processes to build the energy landscape, wherein the monomer can be activated/deactivated by light irradiation. In this way, the supramolecular polymerization and kinetic trap can be independently designed in the energy landscape. When the "dormant" monomer was activated by light in the presence of the seed of the supramolecular polymer, the "activated" free monomer was polymerized at the termini of the seed in a chain-growth manner. As a result, we achieved supramolecular polymers with controlled lengths and a narrow polydispersity. Although photoisomerization has been extensively employed in supramolecular polymer chemistry, most studies have focused on the stimuli responsiveness. In this respect, the present study would provoke supramolecular chemists to revisit stimuli-responsive supramolecular polymer systems as potential candidates for devising living supramolecular polymerization.
authors.affiliation: Department of Materials Science and Engineering, Graduate School of Pure and Applied Sciences, University of Tsukuba , 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.|Molecular Design and Function Group, National Institute for Materials Science (NIMS) , 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Mizuki
authors.initials: M
authors.lastname: Endo
authors.affiliation: Department of Materials Science and Engineering, Graduate School of Pure and Applied Sciences, University of Tsukuba , 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.|Molecular Design and Function Group, National Institute for Materials Science (NIMS) , 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Tomoya
authors.initials: T
authors.lastname: Fukui
authors.affiliation: Molecular Design and Function Group, National Institute for Materials Science (NIMS) , 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Sung Ho
authors.initials: SH
authors.lastname: Jung
authors.affiliation: Department of Applied Chemistry and Biotechnology, Graduate School of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan.
authors.forename: Shiki
authors.initials: S
authors.lastname: Yagai
authors.affiliation: Department of Materials Science and Engineering, Graduate School of Pure and Applied Sciences, University of Tsukuba , 1-1-1 Tennodai, Tsukuba, Ibaraki 305-8577, Japan.|Molecular Design and Function Group, National Institute for Materials Science (NIMS) , 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Masayuki
authors.initials: M
authors.lastname: Takeuchi
authors.affiliation: Molecular Design and Function Group, National Institute for Materials Science (NIMS) , 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047, Japan.
authors.forename: Kazunori
authors.initials: K
authors.lastname: Sugiyasu