English Abstract

Mending Ability of Network Polymers Loosely Cross-linked by Reversible Bonds

Institute of Industrial Science, The University of Tokyo, Meguro-ku, Tokyo, Japan
Nippon Gomu Kyokaishi,(2012),85(8),255-259 General Review in Japanese

Mending ability of network polymers with dynamic cross-links is described. The polymers are networked by thermo-reversible Diels-Alder (DA) reaction of furyl-telechelic prepolymers and tris-maleimide. Because of the moderate molecular weight of the prepolymers, the network polymer is only loosely cross-linked. The mending ability of the polymers is induced by the reversible formation of cross-links. To achieve this mechanism, two conditions are required: the molecular scission upon the material failure occurs at the DA adduct by the retro-DA reaction and the free furan and maleimide groups generated by the chains scission have mobility high enough to reform the DA adduct bridging the crack surfaces. When anthryl-telechelics is used in place of furyl-one, a tough self-mendable elastomer with higher thermal stability can be obtained.

Keywords: Mendable Polymers, Dynamic Bonds, Reversible Cross-links, Telechelics, Molecular Mobility