English Abstract

Block Copolymer-based Supramolecular Elastomers

Atsushi NORO
Department of Applied Chemistry, Graduate School of Engineering, Nagoya University, Nagoya, Aichi, Japan
Nippon Gomu Kyokaishi,(2017),90(1),9-13 General Review in Japanese

Block copolymer-based supramolecular elastomer is one of the thermoplastic elastomers composed of glassy block A and melt hydrogen-bonded block B, both of which are connected to each other by a covalent bond. Such a block copolymer-based supramolecular elastomer can be prepared via living polymerization followed by solvent-casting. Poly(4-vinylpyridine)-b-[poly(butyl acrylate)-co-polyacrylamide]-b-poly(4-vinylpyridine) triblock copolymer serving as a supramolecular elastomer showed better mechanical properties than poly(4-vinylpyridine)-b-poly(butyl acrylate)-b-poly(4-vinylpyridine) triblock copolymer as a conventional thermoplastic elastomer without hydrogen bonding functional groups, in spite of having almost the same degree of polymerization of a glassy end block/a melt middle block and the total average molecule weight. The much better mechanical properties were attained when the triblock copolymer with larger melt middle block was used. Furthermore, if an incorporation ratio of hydrogen bonding functional groups into a melt middle block is increased, the maximum stress σmax increases while the elongation at break εb decreases; therefore, we found that the best mechanical properties were attained at the optimum incorporation ratio.

Keywords: Block Copolymer, Supramolecular Elastomer, Thermoplastic Elastomer, Melt, Hydrogen Bonding, Mechanical Property, Noncovalent Bonding, Dynamic Cross-link