【摘要】 本研究针对航天器界面材料对高导热、绝缘、低迁移特性的要求,基于分子链缠结理论,自制长链烷基改性硅油（AMS）和含氟碳长链改性硅油（FPS）作为基体,以类球状氮化铝和片状氮化硼为导热填料,制得低迁移绝缘导热硅脂界面材料。通过不同粒径填料的粒径复配、发挥不同形貌填料的协同作用、填料表面改性等,导热硅脂的导热性能可达2.51 W/（m·K）,其体积电阻为3.1×1015Ω·cm,击穿电压为10.1 kV·mm^-1。对以自制改性硅油为基体制得的导热硅脂进行迁移性能测试,同时对基体硅油进行表面张力和接触角测试,结果表明,导热硅脂的迁移特性与基础油在迁移测试板上的接触角具有相关性。通过引入长支链增加硅油分子链缠结、改善基础油在涂覆面上的接触角,可有效降低导热硅脂的迁移。更多还原

【Abstract】 Aiming at the requirements of the spacecraft interface materials with high thermal conductivity, insulation property and low migration characte-ristics, based on the molecular chain entanglement theory, the self-made long-chain alkyl modified polysiloxane（AMS） and fluorinated polysiloxane（FPS） were prepared as matrix, and spherical aluminum nitride and flake boron nitride were used as thermal conductive fillers to prepare the thermal conductive grease. Through compounding the particle size of fillers with different particle sizes, exerting the synergistic effect of fillers with different morphologies and modifying the surface of the fillers, the thermal conductivity, the volume resistance and the breakdown voltage of the thermal conductive grease can reach 2.51 W/（m·K）, 3.1×10¹⁵ Ω·cm and 10.1 kV·mm^-1. Based on the results of the migration test of thermal conductive grease, made from the self-made modified silicone oil with similar viscosity, of which the surface tension and contact angle test were carried out, it can be concluded that the oil migration characteristics of the thermal conductive grease is related to the contact angle of the base oil on the test panel. Increasing the molecular chain entanglement of silicone oil and improving the contact angle of the base oil on the coated surface can effectively reduce the migration of thermal conductive grease.更多还原