Study On Low Temperature Cured Polyimide Resins

Polyimide composites are an important class of thermally stable materials. Polyimide composites have been widely used in aerospace, microelectronics and other industrial fields because of its excellent properties, such as heat resistance, mechanical properties, electrical insulation and chemical resistance. The preparation of the traditional thermosetting polyimide composite materials takes a long period of time and needs high processing temperature, so it costs much to product polyimide composites. All these issues above have limited the practical applications of composite materials.In this study, four kinds of the polyimide with different degree of polymerization were synthesized by introducing the isoimide to the main structure. The results showed that, the acetylene-terminated polyimide resin with a low viscosity, wide processing window and nice heat resistance has a curing temperature in the range of200-250℃witch can reduce the processing temperature and costs effectively. The properties of the resin such as viscosity, heat resistance have increased with the increase in the degree of polymerization, but its solubility has decreased.A series of properties of fluorinated polyimide are studied in this paper. We synthesized polyimide resin with different contents of TFMB. We manufactured fluorinated polyimide composites and tested its thermal properties, mechanical properties and electric properties. The results showed that, fluorinated polyimide composites has not only low melt viscosity but also wide processing window, and provides good conditions for the processing of composites. Fluorinated polyimide composites that enhanced by quartz fiber has good performance on electrical properties.