电子束固化树脂基复合材料中碳纤维表面改性研究

Effect of Properties of Carbon Fiber Surface Modified by Anodic Treatment and a Coupling Agent on Electron Beam Cured Epoxy Composites

利用阳极氧化方法和偶联剂对碳纤维表面的物理和化学性质进行改性。采用原子力显微镜 (AFM )和X射线光电子能谱 (XPS)分析了碳纤维表面改性前后的形貌和化学成分的变化 ,利用Kaelble法计算了碳纤维的表面能。研究结果表明 ,阳极氧化改性的碳纤维表面粗糙度增加 ,表面活性官能团增多 ,表面能中极性成分增加明显。碳纤维表面引入的活性氮和化学吸附的碱性物质使电子束固化复合材料界面处的引发剂中毒 ,复合材料界面性能减弱。与电子束固化工艺相匹配的偶联剂在碳纤维与树脂基体之间形成化学桥 。

A double modification method of carbon fiber surface physical and chemical properties was presented by which the carbon fibers were electrochemically oxidized and subsequently coated with an electron beam compatible coupling agent. The treated and untreated carbon fiber surface chemical properties and morphology were analyzed using atomic force microscopy(AFM) and x-ray photoelectron spectroscopy(XPS). And the carbon fiber surface energy was calculated through Kaelble method using contact angle miasurement. The results show that the roughness and reactive groups of carbon fiber surface increase after anodic oxidization, moreover, polar composition of surface energy increase obviously. During EB curing the nitrogen-containing groups and basic species chemisorbed by carbon fiber surface restrain the initiatiors in the interface of compostites, resulting in the weaker adhesion between the carbon fiber and the matrix. The coupling agent, acting as chemical bridge between the carbon fibers and the matrix, improves the interfacial properties of EB cured composites.