电化学氧化表面处理提高粘胶基碳纤维的界面粘结性能

通过动力学的方法研究了电化学处理前后接触角的变化 ,并用其表征碳纤维表面润湿性能的改变 ;通过拔出实验测定电化学处理前后碳纤维与树脂之间粘结性能的变化。结果表明 ,电化学处理后 ,碳纤维表面的润湿性大大改善 ,碳纤维与树脂的粘结程度提高至原来的 14 0 %～ 160 % ;研究还发现 ,不同种类的电解质电化学处理后对碳纤维表面的润湿性及其拔出强度的影响不同 ,( NH4) 2 SO4处理的碳纤维的润湿性能和拔出强度最好 ,H2 SO4处理的润湿性较之 Na OH的好 ,但拔出强度却不如 Na OH处理的高。且拔出强度越高 ,其断裂的模式趋向于单剪切断裂 ,拔出强度降低 ,其断裂变为多剪切断裂甚至为粉碎性断裂。

The Improvement of the Interfacial Adhesion on Rayon-based Carbon Fibers After Electrochemical Surface Treatment

A dynamic method for measuring the wettability of Rayon|based carbon yarn was devised which was based on the rate of wicking of a test liquid by a bundle of the yarn. Contact angles were calculated from the free energy values. A modified pull|out experiment was carried out to measure the interfacial adhesion between carbon fibers and resin. It was shown that after the electrochemical treatment, the wettability was improved greatly. Pull|out experiments showed a significant improvement after the treatment, about 140%~160% as large as that of the untreated. It was also found that with different kinds of electrolytes, the changes in the wettability and pull|out strength are different. (NH 4) 2SO 4 contributes the best wettability and pull|out strength to carbon fibers. H 2SO 4 offers the better wettability but lower pull|out strength than NaOH. It was found that, with the increasement of the pull|out strength, the fracture of the carbon fibers tends to be two|shear or single|shear. But if the pull|out strength is lower, the fracture is multi|shear.