Self-healing superhydrophobic polyvinylidene fluoride/Fe3O4@polypyrrole fiber with core–sheath structures for superior microwave absorption

Abstract

Self-healing superhydrophobic polyvinylidene fluoride/Fe3O4@polypyrrole (F-PVDF/Fe3O4@PPyx) fibers with core–sheath structure were successfully fabricated by electrospinning of a PVDF/Fe3O4 mixture and in situ chemical oxidative polymerization of pyrrole, followed by chemical vapor deposition with fluoroalkyl silane. The F-PVDF/Fe3O4@PPy0.075 fiber film produces a superhydrophobic surface with self-healing behavior, which can repetitively and automatically restore superhydrophobicity when the surface is chemically damaged. Moreover, the maximum reflection loss (RL) of the F-PVDF/Fe3O4@PPy0.075 fiber film reaches −21.5 dB at 16.8 GHz and the RL below −10 dB is in the frequency range of 10.6–16.5 GHz with a thickness of 2.5 mm. The microwave absorption performance is attributed to the synergetic effect between dielectric loss and magnetic loss originating from PPy, PVDF and Fe3O4. As a consequence, preparing such F-PVDF/Fe3O4@PPyx fibers in this manner provides a simple and effective route to develop multi-functional microwave absorbing materials for practical applications.