Aerospace Engineering expects breakthrough of fluorosilicone Technology

　　Author: Li Hongqian article source: China Chemical Newspaper clicks: 95 update time: 2011-09-09 Sinochem New Network News "a generation of materials, a generation of equipment", with the implementation of manned spaceflight, Chang'e project and other key projects, led to the development of new material technology in China, but at present China's high-tech industry is in urgent need of many hurdles. The key material still depends on import. "Organofluorosilicone materials are important supporting materials for the aerospace industry. Our country should take the important equipment demand and professional development as the traction, and organize the application units and materials research and production units to tackle the key problems in the short term, aiming at the key organofluorosilicone monomers and products urgently needed by the aerospace industry. The localization of some products. " Zhao Yunfeng, a researcher at the aerospace materials and Technology Institute, emphasized last week in an interview with reporters. Special organosilicon fluoride materials with unstable properties in China must satisfy many limiting conditions, such as high and low temperature, vacuum, radiation, space environment, special media and so on. These materials often represent the highest level in this field. At present, most of them are monopolized by several professional companies in developed countries, such as DuPont, Dow Corning, General Electric Appliances in the United States, Shinye, Daijin in Japan, and Soviet Company in Europe. Although large foreign companies have invested in factories in China in recent years, the export of key technologies and materials that may be used in military equipment is prohibited to China, which seriously restricts the development of high-performance equipment and the improvement of equipment performance. Zhao Yunfeng pointed out that the performance and quality of some localized high-end materials are still unstable, it is difficult to ensure timely supply. At the same time, low-level repetitive products more, did not achieve generalization, serialization and standardization, part of the product order quantity is too small, production line maintenance is difficult. Fluorosilicone industry in China started late compared with developed countries, but with the continuous growth of the research team, the quality of organofluorosilicone materials has been improved continuously, and more and more kinds of organofluorosilicone materials, especially in the last 20 years entered a period of rapid expansion. With the emergence of high performance materials such as low temperature fluoroether rubber, perfluoropolyether liquid rubber, low temperature perfluoroether rubber, high temperature silicone-nitrogen rubber, radiation-resistant long-life silicone rubber, low compression deformable fluororesin and other new materials, the technical progress and application of fluorosilicone materials have been greatly promoted, and then the development of space equipment technology has been promoted. Exhibition. Organofluorosilicone materials are characterized by many varieties, small batches and high technology content. Zhao Yunfeng classified them according to their application characteristics in aerospace industry. "As an ideal sealing and damping material, fluorine rubber and silicone rubber are widely used." He introduced, by function classification, mainly including rubber sealing materials, rubber damping materials, thermal conductivity and conductive rubber and other products. At the beginning of the development of China's aerospace industry, a large number of special rubber materials were developed. The main applications in the aerospace field are silicone rubber, fluorosilicone rubber, fluororubber, carboxyl nitroso fluororubber, fluoroether rubber and so on. Polytetrafluoroethylene (PTFE) is a kind of fluorine-containing plastics, which has incomparable solvent resistance, chemical stability, thermal stability and chemical inertia compared with other materials. Many fiber-reinforced PTFE products have been used in China's aerospace products. Zhao Yunfeng pointed out that at present there is still a lack of high-end, special modified varieties, such as PTFE, which can be used to process dynamic seals with high elongation and low permanent deformation. It is reported that polytrifluorochloroethylene (PCTFE), suitable for cryogenic sealing of liquid oxygen liquid hydrogen, has been mass produced and supplied in China. Regarding silicone resins with excellent heat resistance and dielectric properties, Zhao Yunfeng pointed out that the dielectric properties of these materials are relatively stable under various environmental conditions, but the disadvantages are low mechanical strength and high pressure molding. At present, Russia has carried out a thorough and systematic study on silicone resin, and has successfully applied silicone composite materials to strategic missiles, rockets and space shuttles. Polysilicone acetylene resin prepared by Institute of Chemistry of Chinese Academy of Sciences has melting properties and is expected to be used as matrix resin of ablation resistant composite materials. In addition, Zhao Yunfeng introduced that the existing space thermal protection coating system mainly includes silicone, epoxy, phenolic aldehyde and other systems, applied to the surface of space spacecraft and different instruments and equipment, is to ensure that the spacecraft internal structure components, instruments and equipment in the space environment in a suitable temperature range, and can work properly key materials. . According to the thermal control requirements of various spacecraft, various kinds of thermal control coatings with different grades, different solar absorption ratios and different infrared emissivity have been developed in China. Concentrating efforts on tackling key problems concerning the current situation of dependence on imports of many key materials, Zhao Yunfeng pointed out that China should actively exert its institutional advantages and make good plans to focus on the key monomers and products of key organofluorosilicone products urgently needed by China's high-tech industries, drawing on important equipment needs and professional development. We will set up a research team which combines production, teaching and research, application units and materials research and production units to tackle the key problems and strive to realize the localization of these products in a short period of time. On the other hand, enterprises should give full play to their initiative to innovate and encourage them to lead the research and development of new products. At the same time, enterprises should give full play to the advantages of industry management to realize the self-sufficiency of the scarce key monomers in China and realize the production and serialization of organofluorosilicone materials. "It should be said that organosilicon silicone products are in the aerospace industry.