将二氧化硅(SiO2)纳米颗粒用阳离子表面活性剂——十六烷基三甲基溴化铵(CTAB)修饰后,加入到含有L–丙氨酸的新型光学活性聚酰胺酰亚胺(PAI)中,采用新型超声波空化技术,制备出一种功能性的PAI/SiO2复合材料。研究了SiO2纳米颗粒含量对复合材料的复合情况和耐热性能的影响。利用傅立叶变换红外光谱仪、X射线衍射仪、扫描电子显微镜、透射电子显微镜、热重分析仪等对复合材料的结构、表面形貌和热稳定性进行表征。结果表明,SiO2纳米颗粒与PAI成功复合;当SiO2纳米颗粒含量为10%时,复合材料的表面形貌最佳,SiO2纳米颗粒均匀分散在PAI基体中;复合材料失重10%时,热分解温度可达410℃,800℃下的残炭率为45.0%,极限氧指数为35.5%,热稳定性有了一定的提升。
The silica(SiO2)nanoparticles were modified by cationic surfactant cetyltrimethylammonium bromide(CTAB)and added to the novel optically active polyamide imide(PAI)containing L-alanine,using a new type of ultrasonic cavitation technology to prepare a functional PAI/SiO2composite.The effects of the content of SiO2nanoparticles on the composite and heat resistance of the composites were studied.Fourier transform infrared spectroscopy(FTIR),X ray diffraction(XRD),scanning electron microscopy(SEM),transmission electron microscopy(TEM)and thermogravimetric(TG)analysis were used to study the structure and surface morphology and thermal stability of the composites.The results show that the SiO2nanoparticles are successfully compounded with PAI.When the content of SiO2nanoparticles is10%,the surface morphology of the composites is the best,and the nanoparticles are uniformly dispersed in the PAI matrix.When the weight loss is10%,the thermal decomposition temperature can reach about410℃,the carbon residue at800℃is45.0%,LOI is35.5%,and the thermal stability is improved.