室温固化导热阻燃有机硅电子灌封胶的制备及性能研究

Preparation and Properties of Room Temperature Vulcanizing Silicone Encapsulant with Thermal Conductivity and Flame Retardance

以不同粘度端乙烯基硅油复配体系为基础胶,含氢硅油为交联剂,氧化铝为导热填料,氢氧化铝为阻燃剂,制备了具有良好导热、阻燃性能的可室温固化的有机硅电子灌封胶。研究了基础胶的乙烯基含量、含氢硅油活性氢含量、填料表面处理用偶联剂种类及用量、氧化铝(Al2O3)与氢氧化铝(Al(OH)3)用量对电子灌封胶性能的影响。结果表明,当以质量比为1∶1的SiVi-300(300mPa.s)和SiVi-1000(1000mPa.s)为基础胶、活性氢质量分数为0.22%的含氢硅油为交联剂、偶联剂KH570为填料表面处理剂(用量为填料量的0.5%(质量分数))、基本配方为m(基础胶)∶m(Al2O3)∶m(Al(OH)3)=100∶140∶60时,电子灌封胶的粘度为3900mPa.s,导热系数为0.72W/(m.K),阻燃性能达到UL 94-V0级,力学性能较佳,电学性能优良,具有最好的综合性能。

Room temperature vulcanizing silicone encapsulant with thermal conductivity and flame retardance was prepared with vinyl end silicone oil mixture as basic gum, organohydrogenpolysiloxane as crosslinking agent, Al2O3 as thermal conductive filler and Al（OH）3 as flame retardant. The influence of vinyl content of basic gum, reactive hydrogen content of organohydrogenpolysiloxane, kind and dosage of the surface treatment agent, ratio of A12O3 and Al（OH）3 on properties of silicone encapsulate were investigated. The results show that silicone encapsulant possesses optimal synthetic properties and has a viscosity of 3900mPa · s, thermal conductivity of 0. 72W/（m · K）, flammability classification of UL94 V-0, good mechanical properties and excellent electrical properties, when the basic gum was the vinyl end silicone oil mixture including 50wt% SiVi-300 and 50wt% SiVi-1000, the crosslinking agent is the organohydrogenpolysiloxane containing 0. 22wt% Sill group, the surface treatment agent is KH570 and its dosage is 0. 5wt% of fillers, the ratio of basic recipe is rn（basic gum） ： m（Al2O3） ： m（Al（OH）3）=100 ： 140 ： 60.