聚酰亚胺／纳米Al2O3-SiO2和聚酰亚胺／纳米Si3N4杂化材料的结构与性能研究

Structure and Properties of Polyimide/Nano Al2O3-SIO2 and Polyimide/Nano Si3N4 Hybrid Materials

将纳米Al2O3-SiO2、Si3N4分别均匀分散于聚酰亚胺（PI）前驱体聚酰胺酸中，经过热亚胺化制备了PI／纳米Al2O3-SiO2和PI／纳米鼠N4杂化材料。通过傅里叶变换红外光谱仪、X射线衍射仪、高温微量热天平、静态热机械分析仪和差示热分析仪对杂化材料的微观结构及热性能进行了研究，结果表明，杂化材料中聚酰亚胺和无机纳米粒子之间存在相互作用，形成了复合相态结构；加入纳米Al2O3，SiO2、Si3N4后杂化材料的热稳定性均高于纯聚酰亚胺，但并不完全随无机纳米粒子含量的增加而提高；与纯PI相比，在90～130℃的温度范围内PI-8％Al2O3-SiO2、PI-8％鼠Si3N4热膨胀系数分别降低了约11％和47％，加入8％纳米Al2O3-SiO2、Si3N4后杂化材料的热导率分别提高了约8％和13％。PI／纳米Al2O3-SiO2、Si3N4杂化材料不仅保留了PI原有的优异性能，而且充分发挥了纳米无机粒子对PI的特殊改性性能。

Nano Al2O3-SiO2 and nano-Si3N4 were dispersed in a solution of polyamic acid （PAA） separately, and hybrid polyimides were obtained through imidization. The＇ micro-structure and thermal propertiesof the hybrid materials were characterized using Fourier transform infrared （FT-IR） spectra, X-ray diffraction, TG, TMA and DSC. It showed that there was interaction between polyimide （PI） matrix and nano-particles. Compared with neat PI, the thermal expansion coefficients of PI-8 % Al2O3-SiO2 and PI-8 % Si3N4 decreased by 11% and 47 % in the temperature range of 90-130 ℃, and the thermal conductivity coefficients increased 8 % and 13 %, respectively.