writer：Chenting Cai, Yue Zhang, Xueting Zou, Rongchun Zhang*, Xiaoliang Wang, Qiang Wu and Pingchuan Sun*
keywords：epoxy resin, graphene, nanocomposites, self-healing, Diels–Alder
source：期刊
specific source：RSC Advances, 2017, 7, 46336–46343
Issue time：2017年
The development of self-healing and recyclable crosslinked polymeric materials has drawn considerable attention in recent years. However, the bulk healing or remending speed is usually slow due to the high viscosity of high Mw polymers, and the low rate of thermal conduction from material surfaces into the central matrix. Herein, a rapid self-healing and recyclable high-performance crosslinked epoxy resin (ER)/graphene nanocomposite is reported by simultaneously incorporating thermally reversible Diels–Alder (DA) covalent bonds and multiple-responsive graphene into the ER matrix. Therefore, graphene in proximity to the DA crosslinkages can instantly trigger the retro-DA reactions by converting the absorbed energies (e.g. infrared light, microwave, etc.) into heat, and thus enables rapid self-healing and recycling. Furthermore, the well-dispersed graphene (<1 wt%) could significantly enhance the mechanical strength of the ER. In situ variable temperature solid-state NMR spectroscopy was used to monitor the reversible DA reactions at the molecular level, and the high healing and recycling efficiency of ER/graphene nanocomposites was well demonstrated by multiple approaches.