Research On The Thermal Stability Of PI/TiO₂ Nanocomposite Film

The inorganic nanoparticles are added to the polymer through a certain process, can be made into a composite film has excellent dielectric properties, having good mechanical, electrical and thermal properties, widely used in electrical engineering, and technology and microelectronics. Inorganic titanium dioxide, has a wide band gap, light, electric connection, has a strong ability to absorb ultraviolet rays, while its dielectric constant and heat capacity is also strong, and as nanoscale inorganic particles, their physical and chemical properties is also very good, therefore, to polyimide matrix nanocomposite films with excellent performance, it gained wide attention.This article was prepared by in-situ polymerization of different components of PI / TiO₂ composite film having a film thickness of about 30 microns. TiO₂ component were 0%, 5%, 10%, 15%, 20%. Electronic and optical microscopy, scanning electron microscopy composite film microstructure; the use of differential thermal analyzer, the thermal stability of Corona and Corona aging equipment Films aging life. By summarizing experimental data, Nano TiO₂ component aging affects the life of the thermal stability of the composite film and corona, and then analyzes the impact mechanism.Join the polyimide matrix inorganic nanomaterials can significantly improve the corona resistance to aging ability composite films, but also to improve the breakdown field strength and dielectric constant properties, these phenomena have been studied by many scholars of proof its theory more perfect, but for the thermal properties of the composite film, few studies, the main purpose of this paper to study the thermal properties of the composite film, and to analyze and study its mechanism. Experimental results show that nano-TiO₂ particles increases the thermal stability of the film, the composite film composition 5% weight loss temperature of 10% and 50%, respectively, compared with pure film improved 19.3 ℃ and 20.7 ℃. DTA curve peak temperature of the composite film are higher than pure film, 5% of the component films peak temperature was 637.8 ℃, pure film raised 40.1 ℃, DTA curve peak shape with the increase of the reaction components is gradually narrowed, peak and the sharp increase in thermal conductivity properties of composite films increased.By studying film microstructure during the thermal decomposition segment changes may not know, the nanoparticles hinder the thermal motion of polyimide molecules, slowing the diffusion film produced during decomposition empty area of nanoparticles in the matrix forming a skeleton structure, improve the thermal conductivity and the rigidity of the film, organic- inorganic phase at the interface between the polyimide molecules have better thermal stability.