Toughening and rapid self‐healing for carbon fiber/epoxy composites based on electrospinning thermoplastic polyamide nanofiber
Boxue Chen, Haopeng Cai, Chi Mao, Yu Gan, Yinglong Wei
Abstract
Abstract This article fabricated toughening and self‐healing carbon/epoxy composites based on electrospinning thermoplastic polyamide nanofiber (PAnf). When the incorporation of PAnf was merely 1.2 wt%, the interlaminar shear and bending strength of composites increased by 17.6% and 14.7%. The two main toughening mechanisms were the entangled porous nanofiber structure with a large specific surface area and the strong interface resulting from the interaction between PAnf and epoxy. Multiple short beam shear cycles generating interlaminar fracture were conducted to evaluate the healing efficiency. The obtained results for three damage‐healing cycles achieved 110.4%, 88.4%, and 70.1%, respectively. The melting thermoplastic PAnf would thermally expand, flow across microcrack, and fill delamination at healing temperature. This process was the inherent characteristic of thermoplastic PAnf, and thus, the composites can heal the damaged region rapidly and repeatedly. Moreover, PAnf with low incorporation showed no adverse effect on the storage modulus and T g of composites, which maintained their original properties.