writer：Yinxin Yang, Lingyun Huang, Ruiyao Wu, Weifeng Fan, Quanquan Dai, Jianyun He, and Chenxi Bai
keywords：1
source：期刊
Issue time：2020年
Vitrimers endow cross-linked polymers with malleability and reprocessability via exchange reactions. However, designing of reprocessable, shape-memory polymer materials with high-strength via catalyst-free method remains a challenge under mild conditions. Here, we propose a facile strategy to address this dilemma by introducing the exchangeable imine bond and N-coordinated boroxine into polybutadiene (PB)-based network. Specifically, the PB grafted with 2-aminoethanethiol is reacted with the formyl group of the phenylboronic acid and dehydrated to form the dual dynamic covalently cross-linked network at room temperature. The dynamic network draws on the advantage of imine (toughness) and N-coordinated boroxine (strength), making the PB-based materials exhibit favorable malleability, mechanical property, reprocessability, and thermal-induced shape memory behavior. We can obtain customized high mechanical properties by tuning the crosslinking density, and the tensile strength reaches to a high value (12.35 MPa) without fillers or any other additives. Meanwhile, the unique network framework makes the material recycle over several times without sacrificing its property. This work presents a facile and effective approach to achieve multifunctional polymer with customized attributes. Besides, this strategy can recycle end-of-life rubber to alleviate environmental pollution and provide inspiration for fabricating targeted materials by uniting the dynamic covalent or non-covalent bonds.