▎ 摘　　要

Mechanical and self-healing properties are two vital factors of polymer materials. Herein, the mechanical and microwave-induced self-healing performance of Graphene-CNT (G-CNT)-reinforced thermoplastic polyurethane (TPU) composites was studied. Three strategies were designed to prepare different combined G-CNT 3D heterostructures to reinforce the TPU composites. It shows that the heterostructures may induce a synergistic effect that improves the mechanical and self-healing properties of TPU composites. A greater combination degree of the G-CNT led to a more significant synergistic effect that improves the tensile strength. The highest degree of G-CNT in the G-CNT/TPU composite reached a maximum. It may be attributed to the improved interface bonding on the interface between the G-CNT and TPUmatrix. But the healing efficiency first increased and later decreased as the combination degree of G-CNT increased, which may be due to the further improved interface bonding, and mixed microwave coupling mechanisms of interfacial polarization and non-unifor mintensity distribution of microwave fields induced by the G-CNT heterostructures. (C) 2017 Elsevier Ltd. All rights reserved.