Research progress on etching modification of carbon fiber and aramid fiber and the interface bonding performance of their composite materials

As reinforcement in composite, fibers play an important role in achieving stress transfer and bearing external loads. The adhesion performance of the fiber and the resin matrix greatly depends on the microscopic morphology and chemical properties of the fiber surface, and the strength of interfacial adhesion determines the performance of the composite. In order to improve the interfacial adhesion property of fiber and resin matrix, it is very necessary to carry out effective modification treatment on the fiber surface before application. Among various methods, etching involves physical and chemical changes on the fiber surface at the same time. It has efficient surface modification ability to significantly change the physical and chemical properties of the fiber surface. The application of surface etching in carbon fiber and aramid fiber was summarized. According to the properties of the fiber, some common etching modification processes were proposed, such as acid solution etching, organic solution etching, electrochemical anodization, plasma treatment, microwave radiation and ultrasonic etching. The effects of etching media and etching process on the fiber surface morphology, chemical properties, mechanical properties and the interfacial bonding properties of the composite material were also concluded and compared, and the research progress on the formation mechanism and characterization methods of the interface between fiber and resin matrix was discussed. Besides, this paper also prospected the future development direction and requirements, and indicated that the corrosion behavior of the fiber surface should be valued, and the traditional modification methods and new modification process should be optimized and developed. At the same time, based on the current technologies, more advanced interface characterization methods should be developed to further understand the influence mechanism between fiber surface corrosion behavior and composite interface properties. © 2021, Chongqing Wujiu Periodicals Press. All rights reserved.