宽温域耐15#航空液压油氟硅橡胶性能的研究

采用均聚氟硅橡胶和改性共聚氟硅橡胶,通过机械共混法制备宽温域氟硅橡胶,研究均聚氟硅橡胶/改性共聚氟硅橡胶并用比对胶料物理性能、耐15^#航空液压油性能及耐低温性能的影响。结果表明:随着改性共聚氟硅橡胶用量增大,胶料的硬度逐渐降低,拉伸强度变化很小,拉断伸长率和拉断永久变形逐渐增大但增幅不大,耐15^#航空液压油性能有所降低,耐低温性能明显提高;当均聚氟硅橡胶/改性共聚氟硅橡胶并用比为50/50时,胶料的脆性温度(多试样法)达到-64.7℃,在-50,-55,-60℃下的压缩耐寒系数分别达到0.51,0.44,0.39,低温回缩试验10%回缩率对应的温度达到-67.2℃;当均聚氟硅橡胶/改性共聚氟硅橡胶并用比为70/30时,胶料的耐低温、耐15^#航空液压油综合性能最佳,动密封圈在10个循环周期的台架试验中未出现泄漏、损伤和永久变形现象,在-60~150℃宽温域、15^#航空液压油环境中具有良好的密封性能。

Study on Properties of Fluorosilicone Rubber with Good Resistance against 15# Aviation Hydraulic Oil under Wide Temperature Range

The fluorosilicone rubber with good properties over a wide temperature range was prepared by mechanical blending of homopolymerized fluorosilicone rubber and modified copolymerized fluorosilicone rubber.The effects of the blending ratio on the physical properties,resistance against 15^#aviation hydraulic oil and low temperature resistance of the compound were studied.The results showed that,with the increase of the amount of modified copolymerized fluorosilicone rubber,the hardness of the compound decreased gradually,the change of tensile strength was very small,the elongation at break and permanent deformation at break increased gradually,but the increase was small,the oil resistance decreased,and the low temperature resistance was improved significantly.When the blending ratio was 50/50,the brittleness temperature of the compound(multi-sample method)was-64.7℃,the compression coefficients at-50,-55 and-60℃were 0.51,0.44 and 0.39 respectively,and TR10 was-67.2℃.When the blending ratio of homopolymerized fluorosilicone rubber/modified copolymerized fluorosilicone rubber was 70/30,the rubber compound had the best balanced performance of low temperature resistance and 15^#aviation hydraulic oil resistance,the dynamic sealing ring had no leakage,no damage or permanent deformation after 10 cycles in the bench test and showed good sealing performance in the wide temperature range of-60~150℃and 15^#aviation hydraulic oil environment.