Abstract:

Hexamethylene diisocyanate (HDI) was used as an intermediate medium to graft the carbon fiber (CF) oxidized by acid potassium permanganate solution, the polymethyl methacrylate (PMMA) hydrolyzed in hydrochloric acid solution and the carboxylated hydrogenated nitrile rubber (HXNBR) to form three-phase grafting interface. Fourier transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to microscopicly characterize the three-phase composite interfaces before and after the modification and the co-grafting. The result of FTIR showed that HDI reacted with resins, damping materials and fibers to form new chemical bonds-amide bonds. The result of scanning electron microscopy (SEM) indicated that the interface of CF and PMMA after the modification and the HDI grafting became rough, and there were more binding sites between them. The thermoplastic damping composite laminates were fabricated by co-grafting process and characterized by macroscopic characterization, and the extraction force of the fiber from the damping material was increased by 90.7% by the H extraction test. The interlaminar shear stress of thermoplastic damping composites increased by 63.6% by interlaminar shear test. The loss factor of the specimen embedded with a thinner damping layer (0.1mm) was about 2.9 times that of the specimen embedded without the damping layer by the free vibration attenuation test. The effectiveness of modification and co-grafting was verified.

Key words: embedded co-grafted thermoplastic damping composites, carboxylated polymethyl methacrylate, hydrogenated carboxyl nitrile rubber, co-grafting process, interfacial properties

摘要：

利用六亚甲基二异氰酸酯（hexamethylene diisocyanate，HDI）作为中间介质对经酸性高锰酸钾溶液氧化后的碳纤维（carbon fiber，CF）、盐酸溶液水解后的聚甲基丙烯酸甲酯（polymethyl methacrylate，PMMA）以及羧基氢化丁腈橡胶（carboxylated hydrogenated nitrile rubber，HXNBR）三相表面接枝处理，通过傅里叶红外光谱（FTIR）以及扫描电镜（SEM）对改性前后以及接枝前后三相复合材料微观表征，FTIR结果表明：HDI与树脂、阻尼材料及纤维均发生了化学反应，生成了新的化学键——酰胺键；SEM观测结果表明：经过改性以及HDI接枝后的CF与PMMA表面均变得粗糙，二者之间有了更多的结合位点；通过共接枝工艺制作了热塑性阻尼复合材料层合板，并对其进行宏观表征：通过H抽出实验测得纤维从阻尼材料中的抽出力提高了90.7%，层间剪切实验测得热塑性阻尼复合材料层间剪切应力提高了63.6%，自由振动衰减实验测得嵌入较薄阻尼层（0.1mm）试件的损耗因子是未嵌入阻尼层试件的2.9倍左右，验证了接枝改性的有效性。

关键词: 嵌入式共接枝热塑性阻尼复合材料, 羧基化聚甲基丙烯酸甲酯, 羧基氢化丁腈橡胶, 共接枝工艺, 界面性能