Effects of acid modification on coupling agent amount of basalt fiber surface and mechanical property of BF/epoxy composites

Fiber/resin composites need a good interface, so that the load can effectively pass from matrix to reinforced fiber, fiber surface modification is the main way to achieve this requirement. The method of hydrochloric acid etching the fiber surface of basalt fiber (BF) was adopted. The effects of acid etching on the monofilament tensile strength, adsorption amount of silane coupling agent on fiber surface were studied, and the effects of hydrochloric acid concentration on the mechanical property of BF/epoxy composites were discussed. The results demonstrate that with the increasing of HCl concentration, the monofilament tensile strength of fiber shows a trend of accelerated decline. The fiber etched by 1 mol/L HCl has more surface adsorption quantity of silane coupling agent KH550. The BF-KH550/epoxy composites pretreated by 1 mol/L HCl and silane coupling agent KH550 have relatively greater mechanical properties in bending performance, tensile properties and interlaminar shear strength.