title: Spontaneously Healable Thermoplastic Elastomers Achieved through One-Pot Living Ring-Opening Metathesis Copolymerization of Well-Designed Bulky Monomers.
abstract: We report here a series of novel spontaneously healable thermoplastic elastomers (TPEs) with a combination of improved mechanical and good autonomic self-healing performances. Hard-soft diblock and hard-soft-hard triblock copolymers with poly[exo-1,4,4a,9,9a,10-hexahydro-9,10(1',2')-benzeno-l,4-methanoanthracene] (PHBM) as the hard block and secondary amide group containing norbornene derivative polymer as the soft block were synthesized via living ring-opening metathesis copolymerization by use of Grubbs third-generation catalyst through sequential monomer addition. The microstructure, mechanical, self-healing, and surface morphologies of the block copolymers were thoroughly studied. Both excellent mechanical performance and self-healing capability were achieved for the block copolymers because of the interplayed physical cross-link of hard block and dynamic interaction formed by soft block in the self-assembled network. Under an optimized hard block (PHBM) weight ratio of 5%, a significant recovery of tensile strength (up to 100%) and strain at break (ca. 85%) was achieved at ambient temperature without any treatment even after complete rupture. Moreover, the simple reaction operations and well-designed monomers offer versatility in tuning the architectures and properties of the resulting block copolymers.
authors.affiliation: School of Material Science and Engineering and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University , Tianjin 300072, China.
authors.forename: Ji-Xing
authors.initials: JX
authors.lastname: Yang
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, China.
authors.forename: Ying-Yun
authors.initials: YY
authors.lastname: Long
authors.affiliation: School of Material Science and Engineering and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University , Tianjin 300072, China.
authors.forename: Li
authors.initials: L
authors.lastname: Pan
authors.affiliation: State Key Laboratory of Polymer Physics and Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences , Changchun 130022, China.
authors.forename: Yong-Feng
authors.initials: YF
authors.lastname: Men
authors.affiliation: School of Material Science and Engineering and Collaborative Innovation Center of Chemical Science and Engineering (Tianjin), Tianjin University , Tianjin 300072, China.
authors.forename: Yue-Sheng
authors.initials: YS
authors.lastname: Li
keywords: Grubbs catalyst; ROMP; block copolymers; hydrogen bond; self-healing; supramolecular chemistry; thermoplastic elastomers