Low Dielectric Constant Polyimide-Zirconium Nanocomposites with Improved Thermal Properties

Low-dielectric-constant (kappa) polyimide films with thermal integrity and controllable mechanical strength have been prepared by covalently bonding zirconium complex with lysine to the main chains of polyimide. The presence of chemical bonds between polyimide (PI) and zirconium has great effect on the properties of polyimide films, especially on their thermal and dielectric properties. The dielectric constants of the resultant nanocomposites are lower due to the increased free volume and fewer polar Zr-O-Zr groups, and can be tuned by varying the molar ratio of zirconium(IV) propoxide, Zr(OPr)(4), in the feed. The possibility of obtaining the kinetic parameters of a reaction from a heating rate dependence of DTA peak location, as well as the merits of different peak methods, were also discussed. The composition, particle sizes, and morphological effect of the Zirconium on nanoparticles were determined by the energy dispersive analysis of X-ray (EDAX), and scanning electron micrographs (SEM).