氧化石墨烯/炭纤维复合增强体的制备及对环氧树脂复合材料界面性能影响

Preparation of carbon fibers grafted to graphene oxide as a reinforcement for epoxy matrix composites

摘要: 为了改善炭纤维/环氧树脂复合材料的界面性能，以对硝基苯胺为原料，通过两步重氮化还原反应，在炭纤维表面共价接枝氧化石墨烯，制备出氧化石墨烯／炭纤维（GO/CF）复合增强体。研究了反应机理，并对改性前后炭纤维表面的化学结构、微观形貌、表面粗糙度、单丝拉伸强度和炭纤维/环氧树脂复合材料的界面性能等进行了测试分析。结果表明，接枝GO后，炭纤维表面粗糙度增加了188%，单丝拉伸强度提高了13.2%，断裂伸长率增加12.1%，界面黏结强度提高了80.2%。

Abstract: Graphene oxide (GO) was grafted on the surface of carbon fibers (CFs) by a two-step diazo reaction using p-nitroaniline as the linking precursor. The strength of the covalent bond between the CFs and the GO was estimated by a gradient ultrasound method. The mechanism of the grafting reaction was verified by cyclic voltammetry. Results indicate that the surface roughness, tensile strength and elongation of the GO-modified CFs are increased by 188%, 13.2% and 12.1%, respectively. The interfacial bond strength in the epoxy matrix composite using the modified CFs as a reinforcement increased by 80.2% compared with that of the pristine CFs.