Constructing a new multiscale “soft-rigid-soft” interfacial structure at the interphase to improve the interfacial performance of carbon fiber reinforced polymer composites

The high strength and toughness of Carbon Fiber-Reinforced Polymers (CFRPs) are the main requirements for their properties in various fields. Herein, the "soft-rigid-soft" structure has been designed by us to achieve the aim of the improvement for the CFRP strength and toughness simultaneously. The soft-rigid-soft structural interface layer of CF was firstly constructed by carbon nanotubes (CNT) and Tannin/Aminopropyl isobutyl POSS (TA/NH2-POSS). The interfacial shear strength (IFSS) of the modified carbon fiber composite was 111.94 MPa, which was 84.08 % higher than that of the untreated fiber (60.81 MPa). Moreover the interlaminar shear strength(ILSS) and impact strength were increased by 50.43 % and 80.37 %. Enhancement of interface performance is mainly ascribed to CNT and TA/NH2-POSS, because they can effectively which is more effective to consume energy and decentralize stress. In this paper, the strength and toughness of CFRPs ware effectively improved by the in-depth and detailed design of the "soft-rigid-soft" multi-scale structure.