碳纤维改性对不饱和聚酯自修复复合材料性能的影响

摘要

采用H 2 O2和浓HNO3对碳纤维(CF)表面分别进行氧化处理,得到氧化碳纤维(OCF1和OCF2),采用硅烷偶联剂γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)对OCF1进行接枝处理,得到接枝改性碳纤维(KCF),将改性前后CF应用于不饱和聚酯(UP)自修复复合材料中,分析比较了不同改性剂及改性方法对碳纤维/不饱和聚酯(CF/UP)自修复复合材料性能的影响.利用FTIR、XPS、SEM表征CF与CF/UP自修复复合材料的化学结构与形貌,通过TGA、万能拉力试验机、悬臂梁冲击仪、邵氏硬度计等对复合材料的热稳定性、力学性能及自修复效率进行测试.结果表明:氧化、接枝反应均可增加CF表面的粗糙度和活性官能团含量,从而改善CF与UP基体的界面相容性.其中OCF1/UP自修复复合材料的综合力学性能比OCF2/UP自修复复合材料好,KCF/UP自修复复合材料的力学性能在三者之中最佳,其自修复效率最高,可达67.03%.%The oxidized carbon fibers (OCF1 and OCF2 )were prepared via surface oxidation treatment in H 2 O2 and concentrated HNO3 ,and then modified by silane coupling agent γ-methacryloxypropyltrimethoxysilane (KH-570),to obtain the KH-570 grafting modified carbon fibers(KCF),which were applied to the unsaturated polyester self-healing composites.Effects of different modification agents and modification methods on the properties of car-bon fiber/unsaturated polyester composites were compared.The effect of surface modification of carbon fiber,the structure and the performance of carbon fiber/unsaturated polyester composites were characterized by FTIR,XPS and SEM.The mechanical properties of composites were measured by universal tensile testing machine,izod impact device and shore durometer.The results show that the activity of the carbon fiber's surface functional group content and roughness increases because of the oxidation and grafting reaction,thereby improving the compatibility between carbon fiber and unsaturated resin matrix.The integrated mechanical properties of OCF1/UP composites are better than OCF2/UP composites'.In the three composites,the mechanical properties and the self-healing efficiency of KCF/UP composites are best with self-healing efficiency of 67.03%.