This study reports for the first time the use of water soluble sulfonated octa-phenyl POSS nanowhiskers for the surface treatment for carbon fibres using simple dip-coating method. The water soluble nature of the functionalized POSS makes it appealing from a formulation perspective as it can be applied simply using an aqueous media. The synthesis of the water soluble SOP-POSS was achieved via one-step aromatic electrophilic sulfonation of octaphenyl POSS. Collective results from NMR, XPS and FTIR analysis confirmed the meta mono-substitution of all phenyl rings in the starting material with a sulfonic group, leading to its water solubility. Surface treatment of commercially oxidized and unsized carbon fibres was achieved via simple dip-coating of the fibres in an aqueous media solution containing the synthesized SOP-POSS product. After the dip-coating process, the carbon fibres are homogeneously covered with surface adsorbed SOP-POSS nanowhiskers. Physico-chemical characterization of the fibres investigated by Inverse Gas Chromatography (IGC) revealed an improvement in surface chemical homogeneity associated with a significant increase in surface oxygen contents and an overall level of surface polarity comparable to commercially sized fibres. The interfacial adhesion properties between the treated carbon fibres and an epoxy matrix were investigated by single fibre fragmentation technique. The results of the tests revealed that significant enhancement of interfacial properties was achieved as a result of a combination of physical inter-molecular interactions at the fibre-matrix interface and localized nano-mechanical strengthening of the epoxy. The outcomes of this research lay the path forward for a potential simple surface treatment of commercial carbon fibres for Interfacial property improvement in composites.

这项研究首次报道了使用简单的浸涂法将水溶性磺化八苯基POSS纳米晶须用于碳纤维的表面处理。从配方的角度来看，官能化POSS的水溶性使其具有吸引力，因为它可以简单地使用水性介质施用。水溶性SOP-POSS的合成是通过八苯基POSS的一步芳香亲电磺化实现的。NMR，XPS和FTIR分析的综合结果证实了原料中所有带有磺酸基的苯环均被亚甲基单取代，从而使其具有水溶性。通过在包含合成的SOP-POSS产品的水性介质溶液中对纤维进行简单的浸涂，即可对商业氧化的和未定尺寸的碳纤维进行表面处理。在浸涂过程之后，碳纤维被表面吸附的SOP-POSS纳米晶须均匀地覆盖。通过逆气相色谱法（IGC）研究的纤维的理化特性表明，表面化学均质性的改善与表面氧含量的显着提高以及表面极性的总体水平相媲美，可与市售尺寸的纤维相提并论。通过单纤维断裂技术研究了处理后的碳纤维和环氧基质之间的界面粘合性能。测试结果表明，由于纤维-基体界面处的物理分子间相互作用与环氧树脂的局部纳米机械增强相结合，界面性能得到了显着提高。