LNG储罐用碳纤维的表面处理及其性能分析

Surface treatment and properties of carbon fiber for LNG storage tanks

对LNG储罐用碳纤维进行了表面氨基化处理,分析了氨基化处理对碳纤维表面化学结构、形貌、浸润性能和力学性能。结果表明:三聚氰氯已成功接枝到碳纤维表面,且分别在碳纤维表面形成了—C—NH—和C—N特征峰,以及—C—NH—和C—C=C—C化学键;经过氨基化处理后,碳纤维表面沟槽被填充,EDA和PPD都填充在沟槽中,有助于改善碳纤维与树脂的界面结合能力,创造更多的接触位点;相较于未改性处理的碳纤维,经过氨基化处理后碳纤维的单丝拉伸强度变化幅度不大或略有减小,界面剪切强度明显增大;经过氨基化处理后,碳纤维复合材料的裂纹形成功、裂纹扩展功和总冲击功都有不同程度提高,且裂纹形成功、裂纹扩展功和总冲击功从大至小顺序依次为:CF-PPD、CF-EDA、Untreated CF。

The surface amination of carbon fiber for LNG storage tank were carried out,and the surface chemical structure,surface morphology,wetting property and mechanical properties of carbon fiber before and after the amination treatment were compared and analyzed.The results showed that cyanogen chloride had been successfully grafted onto the surface of carbon fiber,and —C—NH— and C—N characteristic peaks and —C—NH— and C—C C=C C—C chemical bonds were formed on the surface of carbon fiber respectively;After the amination treatment,the grooves on the surface of carbon fiber are filled,and EDA and PPD are filled in the grooves,which helps to improve the interface binding ability of carbon fiber and resin and create more contact sites;Compared with the unmodified carbon fiber,the tensile strength of the monofilament of the carbon fiber after the amination treatment has little change or slightly decreased,and the interfacial shear strength increases significantly;After the amination treatment,the crack formation success,crack propagation and total impact energy of the carbon fiber composite are increased to different degrees,and the order of crack formation success,crack propagation and total impact energy is CF-PPD > CF-EDA > untreated CF.