Carbon nanotubes array reinforced shape‐memory epoxy with fast responses to low‐power microwaves

ABSTRACT In this study, epoxy shape‐memory polymer (ESMP) was infiltrated into the scaffolds of vertically aligned carbon nanotubes (CNTs) array grown by chemical vapor deposition (CVD). In the fabricated CNTs array/ESMP nanocomposite, the CNTs interconnected with each other and a three‐dimensional (3D) network of the CNTs was formed. As a result, both thermal conductivity and electrical conductivity of the CNTs array/ESMP nanocomposite were higher than the random CNTs/ESMP composite fabricated by conventional high‐speed mechanical stirring. In the random CNTs/ESMP composite, the CNTs aggregated seriously in the matrix. Along the CNTs axis, The CNTs array/ESMP nanocomposite showed a higher modulus and hardness than the random CNTs/ESMP composite, as revealed by nanoindentation tests. Under microwave radiation, the temperature of the CNTs array/ESMP nanocomposite increased more rapidly than pristine ESMP and the random CNTs/ESMP composite. Consequently, the CNTs array/ESMP nanocomposite showed a faster shape recovery speed compared with pristine ESMP and the random CNTs/ESMP composite in their microwave‐triggered shape memory behaviors. Especially, the CNTs array/ESMP nanocomposite can recover the deformation fully in response to as low as 60 W microwaves. The presented CNTs array/ESMP nanocomposite with improved mechanical property and fast responses to low‐power microwaves may find potential applications in smart devices. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136 , 47563.