纤维热氧-接枝处理与基体改性对CF/VE复合材料力学性能的影响

Properties of Surface Thermo-chemically Modification of Carbon Fibers and Their Vinyl Ester Composites

针对碳纤维增强乙烯基酯树脂(CF/VE)复合材料界面性能薄弱的问题,通过热氧-接枝的方法对碳纤维表面进行改性,通过添加偶联剂改性树脂,并采用真空辅助成型工艺制备了CF/VE复合材料。通过纤维扫描电镜(SEM)表征和CF/VE复合材料力学性能测试、动态力学测试、界面粘结参数计算以及界面的微观表征验证改性方法的效果。SEM测试表明改性后纤维比表面积和粗糙度提高;TGA测试表明碳纤维氧化温度大于210℃,且氧化温度在600℃时,CF/VE复合材料综合性能最佳;CF/VE复合材料界面性能随隅联剂质量浓度的增大先提高后降低,且在其质量浓度为1%时,层间剪切强度最大,相对于未改性CF/VE复合材料的提高了74.3%;动态力学性能测试(DMA)表明改性CF/VE复合材料的玻璃化转变温度Tg较未改性的提高了约10℃;界面粘结参数A和α的定量计算表明改性CF/VE复合材料界面性能得到较大改善。

In order to improve the weak interface performance of the carbon fiber/vinyl ester composites,we modifed the carbon fiber via surface oxidation and grafting and at the same time changed the resin formulation. It is demonstrated that the interface performance of CF/VE composites has been improved according to the results of SEM characterization,mechanical property tests,DMA tests as well as adhesion parameters calculation. The SEM pictures demonstrate that the specific surface area of the modified CF/VE composites is increased,and the interface strength is greater than the strength of the resin while the unmodified CRFP＇s is not. The oxidation temperature should be set at least over 210℃ according to the TGA testing result. CF/VE composites show better properties when the carbon fibers are oxidated at 600 ℃. The interlaminar shear strength increases at first and then decreases as the coupling concentration increases. When the mass concentration is 1%,the sheer strength rises to the highest,increasing by 74. 3% compared to that of the unmodified CF/VE composites. The glass transition temperature is improved by 10 ℃ from the dynamics mechanics curves. The interface performance of the modified CF/VE composites is improved,confirmed by the quantitative analysis of adhesion parameters.