Fluorosilicone oil is polysiloxane with alkyl side chains containing fluorine, and because of its excellent thermal oxidation stability, cold flow property and cryogenic property, it can be widely used as a high tempe...Fluorosilicone oil is polysiloxane with alkyl side chains containing fluorine, and because of its excellent thermal oxidation stability, cold flow property and cryogenic property, it can be widely used as a high temperature lubricant in the field of military aerospace industry. Two kinds of fluorosilicone oils, FSiO-a and FSiO-b, were synthesized by different pro- cessing means. FTICR MS was used to collect the information on composition and structure of the two polymers, respec- tively. The test results show that the two fluorosilicone oils have different contents of fluorine-containing chain segments (m/ n value), the maximum distribution of m/n value of FSiO-a oil ranges from 0.22 to 0.25, and that of FSiO-b oil ranges from 0.4 to 0.67. Difference in synthesis techniques makes this discrepancy and affects the quality and thermal stability of the fluoro- silicone oils.展开更多
As an essential elastomer used in edge technologies, fluorosilicone rubber(FSR) suffers serious oxidative ageing problem when serving at high temperature. Cerium oxide is generally used as an antioxidant additive but ...As an essential elastomer used in edge technologies, fluorosilicone rubber(FSR) suffers serious oxidative ageing problem when serving at high temperature. Cerium oxide is generally used as an antioxidant additive but remains unsatisfactory. In order to obtain better antioxidant effect on improving the thermal stability of FSR, a kind of cerium-containing polymethylphenyl silicone(PSI-Ce) was synthesized and the structure was verified by Fourier-transform infrared spectroscopy(FTIR) and proton nuclear magnetic resonance(1HNMR). Due to the homogeneous dispersion on molecular scale, PSI-Ce imposed much better antioxidant effect than the commercial CeO2 did, no matter from isothermal degradation at 320 ℃ or thermal-oxidative ageing test at 230 ℃. In particular, after ageing for 72 h,FSR/PSI-Ce(2 phr) maintained 82% of tensile strength and 63% of elongation at break, in comparison to the corresponding values of 48%and 42% for FSR/CeO2(2 phr). Moreover, 2 phr PSI-Ce was equivalent to 0.046 phr CeO2 according to cerium element conservation.展开更多
文摘Fluorosilicone oil is polysiloxane with alkyl side chains containing fluorine, and because of its excellent thermal oxidation stability, cold flow property and cryogenic property, it can be widely used as a high temperature lubricant in the field of military aerospace industry. Two kinds of fluorosilicone oils, FSiO-a and FSiO-b, were synthesized by different pro- cessing means. FTICR MS was used to collect the information on composition and structure of the two polymers, respec- tively. The test results show that the two fluorosilicone oils have different contents of fluorine-containing chain segments (m/ n value), the maximum distribution of m/n value of FSiO-a oil ranges from 0.22 to 0.25, and that of FSiO-b oil ranges from 0.4 to 0.67. Difference in synthesis techniques makes this discrepancy and affects the quality and thermal stability of the fluoro- silicone oils.
基金financially supported by the National Natural Science Foundation of China (Nos. 51573043 and 21805086)the Fundamental Research Funds for the Central Universities (Nos. 222201817001 and 222201814004)+2 种基金supported by the Shanghai Leading Academic Discipline Project (No. B502)the Shanghai Key Laboratory Project (No. ZD20170203)Support from FSIR Advanced Material Co., Ltd.
文摘As an essential elastomer used in edge technologies, fluorosilicone rubber(FSR) suffers serious oxidative ageing problem when serving at high temperature. Cerium oxide is generally used as an antioxidant additive but remains unsatisfactory. In order to obtain better antioxidant effect on improving the thermal stability of FSR, a kind of cerium-containing polymethylphenyl silicone(PSI-Ce) was synthesized and the structure was verified by Fourier-transform infrared spectroscopy(FTIR) and proton nuclear magnetic resonance(1HNMR). Due to the homogeneous dispersion on molecular scale, PSI-Ce imposed much better antioxidant effect than the commercial CeO2 did, no matter from isothermal degradation at 320 ℃ or thermal-oxidative ageing test at 230 ℃. In particular, after ageing for 72 h,FSR/PSI-Ce(2 phr) maintained 82% of tensile strength and 63% of elongation at break, in comparison to the corresponding values of 48%and 42% for FSR/CeO2(2 phr). Moreover, 2 phr PSI-Ce was equivalent to 0.046 phr CeO2 according to cerium element conservation.
