MWCNTs/PES-MBAE复合材料的微观结构与耐热性

Micro-structure and Heat-resistance of MWCNTs/PES-MBAE Composite

以二烯丙基双酚A(BBA)和双酚A双烯丙基醚(BBE)为活性稀释剂、以4,4’-二氨基二苯甲烷双马来酰亚胺(MBMI)为前驱体制备聚合物基体(MBAE),采用聚醚砜(PES)和酸化MWCNTs为改性剂,通过原位聚合法制备MWCNTs/PES-MBAE复合材料。采用TEM和FT-IR分析酸化MWCNTs的改性效果,利用SEM观察材料的微观形貌及相结构。结果表明:经过混酸处理2 h的MWCNTs,其表面被氧化,保持了较大的长径比,且在基体中分散均匀;FT-IR显示在3 448cm^(-1)和1 635 cm^(-1)处存在特征峰,推断其表面存在-COOH;另外,PES与MBAE间呈现两相结构并以"蜂窝"状均匀分散在聚合物基体中。复合材料的耐热性测试结果显示:PES树脂会使材料的热分解温度降低,但MWCNTs会提高材料的耐热性能。当PES质量分数为2%,MWCNTs质量分数为0.02%时,MWCNTs/PES-MBAE复合材料的热分解温度为453.7℃,较基体树脂提高15.4℃。

Polymer matrix(MBAE) was prepared by reactive diluent which contained diallyl bisphenol A(BBA) and bisphenol-A diallyl ether(BBE) with 4,4'-diamino diphenyl methane bismaleimide(MBMI).Polyether sulfone(PES) and acid-MWCNTs as modifiers were used to prepare MWCNTs/PES-MBAE composite was through in-situ polymerization method.Acid-MWCNTs were analyzed by Transmission Electron Microscope(TEM) and Fourier transform-infrared spectroscopy(FT-IR).Microstructure and phase structure of the composite were observed by Scanning Electron Microscope(SEM).The results showed that polar groups could be generated on the surface of MWCNTs with a large ratio of length to diameter in the system of mixed acid for 2 hours,and evenly dispersed in the composites.FT-IR showed that the characteristic peaks were at 3 448 cm^(-1) and 1 635 cm^(-1),to infer the existence of-COOH.PES presented as two-phase structure in MBAE matrix,PES resins evenly dispersed in polymer matrix with "honeycomb" shape.Results of heat resistance of composites showed that the thermal decomposition temperature would decline when MBAE matrix mixed with PES,but acid-MWCNTs can enhance the thermal stability of composite materials.When the content of PES was 2 wt% and acid-MWCNTs was 0.02 wt%,the thermal decomposition temperature of MWCNTs/PES-MBAE was 453.73℃,which is 15.40℃higher than that of matrix resin.