Study On Thermal Aging Property Of Polyimide Hybrid Film With Nano-Al₂O₃

As a kind of functional materials, polyimide (PI) had excellent dielectricity and good mechanical property under high temperature, and it had been applied in the many fields of electrical insulation. Because of the inherent aging distinction, however, the topic about how to prolong the used life by adopting active protection measure became more and more important.Nano-inorganic doped polyimide research is hot spot in recent years. Nano-particle is a tiny number of atoms or molecules composed of atoms or molecules cluster group, nano-particle having the small size effect and surface effects, have a range of excellent performance. Although the various components of composite materials to maintain its relative independence, but the complex property of the material is not the performance of the various components of a simple additivity, but in maintaining the various components on the basis of certain characteristics of the material, composite has the combined performance with synergy effect. The birth of nano-particles has added new content for composite materials research. Scientists put the material described as "21st century's most promising materials."The thermal stabilization of PI hybrid film mixed with nano-Al₂O₃ particles made by ourselves was studied by TG in this article. The results showed that the thermal stabilization of PI hybrid film containing 8wt% nano-Al₂O₃ component is better than that of PI hybrid film containing 4wt% nano-Al₂O₃ component. The thermal decompose kinetics parameters of a series of PI hybrid film with nano-alumina particles in different containing in N2 and air were calculated with the way of Coats-Redfern method. At last, action progression (n), the thermal decompose activation energy (E) and the corresponding collision coefficient (A) were gained at the same time. According to the relation between thermal decompose kinetics and thermal aging, the thermal aging life curves of PI hybrid film with nano-alumina particles in different containing in N2 and air were drawn. The results showed that the way of Coats-Redfern was one of the credible means to forecast the thermal aging life of PI hybrid film.