Surface and interface modification of aramid fiber and its reinforcement for polymer composites: A review

Aramid fiber (AF), which has excellent comprehensive properties such as low density, high specific strength, and high specific modulus, is widely used in composites reinforcement. AF-reinforced composites (AFRPs), which are very suitable for preparing advanced engineering materials, have drawn much attention due to their excellent properties. However, the smooth and chemically inert surface of the AF severely limits its applications. Various methods have been conducted to modify the surface of AF to improve the interfacial adhesion between fiber and matrix. The purpose of surface modification of AF is to improve the surface chemical activity and increase the surface roughness, which aims to achieve an excellent chemical bonding and mechanical interlocking between fiber and matrix. The major focus of this review is the surface and interface modification of AF. In this review, we briefly summarize the recent progress of different surface modification methods of AF and its reinforcement to polymers. Finally, some existing problems of AFRPs as well as future research prospects are discussed.