低热膨胀系数纳米碳化硅/聚酰亚胺复合薄膜的制备与性能

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。 

Preparation and properties of nano-SiC/polyimide composite films with low thermal expansion characteristic

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.