适用于低温声传感器的MEMS密封氟橡胶复合材料合成及性能研究

Synthesis and Properties of MEMS Composite Sealing Materials for Low Temperature Cryoacoustic Sensors

随着我国电力建设向高纬度、高海拔等低温区域推进,变电站噪声测试面临低温问题,特别是低温声传感器密封,面临系列挑战。MEMS(Micro-Electro-Mechanical Systems,微型电子机械系统)密封性能取决于密封圈材料拉伸和压缩形变后的恢复程度,低温会导致密封圈材料玻璃化,进而影响传感器的使用寿命。含氟材料具有优异的耐磨性和耐腐蚀性,广泛用于各类密封件、绝缘材料的制备,但同样面临着低温环境下性能下降的问题。通过在金属有机骨架材料外表面接枝烷基长链合成了一种改性的纳米钛基材料DA-NH2-MIL-125(Ti),以氟橡胶为聚合物基体,DANH2-MIL-125(Ti)为功能填料,通过溶液共混法制备了复合密封材料。得益于NH2-MIL-125(Ti)颗粒外表面中烷基长链较低的极性作用,提升了纳米金属有机骨架颗粒与氟橡胶基质之间的相容性,得到一种高掺杂量的氟橡胶复合材料,当DA-NH2-MIL-125掺杂量为20%时,该复合材料拉伸强度可达19.1MPa,玻璃转化温度由-22℃降低到-31℃,提高了氟橡胶的耐低温性能。

With the development of electric power in low temperature areas such as high latitude and high altitude,a series of challenges have been presented to the sensor sealing technology.The performance of the sealing material depends on its recovery degree after tensile and compression deformation at this temperature.Low temperature will lead to the vitrification of the sealing ring material,thus affecting the service life of the sensor.Fluorine containing materials have excellent wear resistance and corrosion resistance,and are widely used in the preparation of various seals and insulating materials.However,they also face the problem of performance degradation under low temperature environment.In this work,a modified nano titanium based material DA-NH2-MIL-125(Ti)was synthesized by grafting alkyl long chain onto the outer surface of metal organic skeleton material.The composite sealing material was prepared by solution blending with fluororubber as the polymer matrix and DA-NH2-MIL-125(Ti)as the functional filler.Benefiting from the low polarity of alkyl long chain on the outer surface of NH2-MIL-125(Ti)particles,the compatibility between nano metal organic skeleton particles and fluororubber matrix is improved,and a fluororubber composite with high doping amount is obtained.When the doping amount of DA-NH2-MIL-125(Ti)was 20%,the tensile strength of the composite material can reach 19.1 MPa,and the glass transition temperature was reduced from-22℃to-31℃,improving the low temperature resistance of fluororubber.