English Abstract

Design of Self-healing Polymers and High Value-added Urethane-containing Rubber Materials Based on Dynamic Covalent Chemistry

Hideyuki OTSUKA *1
Daisuke AOKI *1
Yasuhiro SHODA *2
Katsuhiko TSUNODA *3
*1:Department of Chemical Science and Engineering, Tokyo Institute of Technology, Tokyo, Japan
*2:Advanced Technology Promotion Division, Bridgestone Corporation, Kodaira-Shi, Tokyo, Japan
*3:Advanced Materials Division, Bridgestone Corporation, Kodaira-Shi, Tokyo, Japan
Nippon Gomu Kyokaishi,(2021),94(2),33-38 General Review in Japanese

In this review paper, the design of self-healing polymers and urethane-containing rubber materials based on dynamic covalent chemistry is described. This review is mainly divided into two parts. In the former part, the design of self-healing polymer networks with autonomously exchangeable C–C bonds or thermally exchangeable S–S bonds is introduced. The incorporation of such dynamic covalent bonds into polymer networks can endow polymer networks with structurally reorganizable properties. Not only self-healing property, but also reprocessability and adhesion capability were observed for the polymer networks with dynamic covalent bonds under appropriate conditions. In the latter part, the application of cross-metathesis reactions of C=C bonds between polybutadienes and olefin-containing polyurethanes to the synthesis of novel polybutadienes with urethane linkages as a source of hydrogen bonds is described. A series of polybutadienes copolymers with different contents of urethane linkages can be prepared by changing the feed ratios of the polybutadiene and olefin-containing polyurethanes in the cross-metathesis reactions. The aggregation structure of deuterated polybutadienes copolymers with different contents of urethane linkages are characterized by small-angle neutron scattering. Cured rubber materials prepared from polybutadienes copolymers with urethane linkages exhibit large energy dissipation at high strain.

Keywords: Dynamic Covalent Chemistry, Polymer Reactions, Self-healing, Polybutadiene, Polyurethane, Olefin Metathesis, Diene System Synthetic Rubber, Tire Application