Abstract With the purpose of improving the interfacial properties of aramid fibers reinforced rubber composites and enhancing the tensile strength of aramid fibers simultaneously, mercapto hyperbranched polysiloxane (HPSi) and functionalized graphene oxide (GO) were used to modify the surface of aramid fibers. Scanning electron microscopy (SEM), Fourier transform infrared (FTIR) spectroscopy and other characterization methods were performed to confirm the process of synergistic modification. Judging from the results of mechanical property tests, it could be acquired that the tensile strength of modified aramid fiber was increased by 16.8%, which could be ascribed to the wrapping effect of GO sheets. The interfacial properties were assessed by the pull-out tests of composites, and the results showed that the maximum pull-out force after synergistic surface modification was increased by 99.3%, which could be mainly related to additive reaction between double bonds and mercapto groups and the promotion of surface energy. More critically, during pull-out test, aramid fiber bundles might bring a part of shear stress into the grafted GO sheets, namely, GO sheets could convert fracture energy into interfacial energy, which would improve interfacial properties dramatically.

中文翻译：

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巯基超支化聚硅氧烷与官能化氧化石墨烯协同改性芳纶纤维表面

摘要 为了改善芳纶纤维增强橡胶复合材料的界面性能，同时提高芳纶纤维的拉伸强度，采用巯基超支化聚硅氧烷（HPSi）和功能化氧化石墨烯（GO）对芳纶纤维表面进行改性。进行了扫描电子显微镜（SEM）、傅里叶变换红外（FTIR）光谱和其他表征方法以确认协同改性的过程。从力学性能测试结果来看，改性芳纶纤维的拉伸强度提高了16.8%，这可以归因于GO片的包裹作用。通过复合材料的拉拔试验评估界面性能，结果表明，协同表面改性后的最大拔出力提高了99.3%，这主要与双键与巯基的加成反应和表面能的提升有关。更关键的是，在拉拔试验中，芳纶纤维束可能会给接枝的 GO 片材带来一部分剪切应力，即 GO 片材可以将断裂能转化为界面能，这将显着改善界面性能。