Self-healing elastomers from supramolecular random copolymers of 4-vinyl pyridine

For the first time hydrogen bonding complexes between poly(4-vinyl pyridine) (P4VP) and its copolymers were employed as a healing concept for building supramolecular materials with self-healability. P4VP and its random copolymers with stearyl acrylate and stearyl methacrylate were first synthesized via UV light-mediated metal-free polymerization using 4-(10H-phenothiazin-10-yl)-N,N-diphenylaniline as organic photocatalyst. Three complexes between the P4VP homopolymer and the obtained copolymers bearing “hairy” side groups with 3,3′-dithiodipropionic acid (DTDP) as a proton donor crosslinker were studied. Owing to the “solvent”-like mantle formed by lowly ordered stearyl side groups, the complex of poly(4-vinyl pyridine-random-stearyl methacrylate) and DTDP exhibited efficient self-healability of complete cuts at room temperature after 30 min, with tensile strength recovery of above 80%. The results of this work suggested that this dynamic supramolecular concept based on P4VP is promising for developing self-healing materials for various applications.