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

With polyimide (PI) materials has been used more and more widely in aerospace, ocean, electronics, and other areas of high performance, due to in some areas of polyimide non-substitutability, more and more scholars focus on discussion and study for the mechanical, electrical, and thermal properties of PI on the more thorough. As is known to all, polyimide materials is currently used to heat the highest level polymer materials, but there are also ageing problems used in specific environment. This problem has been praised by the attention of people, how to take effective measures to prevent the ageing of polyimide materials, and how to accurately estimate the thermal aging life of polymer materials for long term use become an important topic today.Inorganic nanometer particles due to the polymer which are beyond the high temperature resistance, corrosion resistance and friction, and many other advantages got the attention of people, more and more scholars are constantly trying to use inorganic nanometer particle doping polymer material to improve every aspect of the performance. Nano particles doping polyimide film is one of them, people found the mechanics, heat and electrical properties of PI films doped are improved. But the high performance of composite materials is by no means simple adding the performance of components, but on the basis of each component keeping original superior performance, the comprehensive performance of PI hybrid films originated the synergy effect of each component. The birth of the nano particles proposed the future development direction of composite materials and added new content for new materials preparation, and laid a solid foundation.In this paper, the thermal stability of nano Al2O3/PI doped films homemade were analysed with TG. And the thermal decomposition dynamics was calculated in various computational methods based on thermodynamic theory. Through analyzing the advantages and disadvantages of the computational method of dynamic reaction, the Half-Life and Coats-Redfern method were choosed in calculating reaction order(n), activation energy(E) and impact factor(A). After identifying three major parameters above, thermal aging life temperature of nano Al2O3/PI doped films containing4wt%,8wt%,12wt%,16wt%,20wt%,24wt%,28wt%,32wt%nano-alumina particles were calculated, respectively. The limit temperature for long term service of nano Al2O3/PI doped films containing12wt%nano-alumina particles reached maximum,332℃(in the air) and377℃(in the nitrogen), respectively. In addition to these, to compare estimated value of Kapton100CR with actual value of Kapton100CR, Coats-Redfern is certainly one of reliable method to rapidly estimate the thermal aging life temperature of PI doped films.