以原位分散聚合法制备出纳米碳化硅/聚酰亚胺(n-SiC/PI)复合薄膜,采用SEM、热机械分析仪(TMA)、阻抗分析仪和热重分析(TG)研究了所制备薄膜的表面形貌、热膨胀、介电性能及热稳定性。结果表明:SiC粒子均匀分散在PI基体中,复合薄膜的热膨胀系数(CTE)随着SiC含量的增加逐渐减小,SiC质量分数为15%时,CTE降低了11%,且复合膜的热膨胀系数实验值比较接近于Kerner公式的计算值。复合膜的介电常数和介电损耗随着填料含量的变化而变化,但始终维持在较低的范围内,并在相当大的频率范围内保持稳定。
Nano-SiC/Polyimide(n-SiC/PI) composite films were prepared by using in-situ dispersive polymerization.The surface morphology,thermal expansion,dielectric properties and thermal stability of n-SiC/PI were studied by SEM,thermal mechanical analysis(TMA),impedance analyzer and thermal gravimetric analysis(TG) respectively.The results show that n-SiC particles are dispersed in the PI matrix evenly by employing the in-situ polymerization.The coefficient of thermal expansion(CTE) of n-SiC/PI composite films decreases with the increasing of the SiC content,while the experimental data could be analyzed by Kerner model closely.The CTE of PI with n-SiC mass fraction of 15% decrease about 11% than that of the pure PI.The dielectric constant and dielectric loss of films vary with the content of n-SiC fillers,remaining in the lower range and stable in a wide frequency range.