Preparation, Morphology and Dielectric Properties of Nano-Tic/Polyimide Composite Films

A series of nano-titanium carbide doped polyimide (nano-TiC/PI) composite films were successfully prepared via in situ polymerization. The microstructure of the obtained composite films was characterized by the scanning electron microscopy (SEM). The effects of different TiC contents on the mechanical and thermal properties of composite films were investigated. Dielectric properties of the nano-TiC/PI composite films were analyzed in detail with respect to different experimental parameters including frequency and filler concentration. Results indicated that the TiC particles dispersed homogeneously in PI matrix when its' content was below 15 vol.%. The addition of TiC particles could effectively improved the thermal stability of composite films. In comparison with pure polyimide film, the dielectric constant of the composite films with 5 vol.% TiC was significantly increased by thirteen times while the loss tangent only increased a little. Moreover, the composite films exhibited good dielectric stability over a wide range of frequency. The development of these novel polyimide composite films with favorable dielectric properties are potential for embedded capacitor applications.