加成型防沉降有机硅灌封胶的制备  

Preparation of Addition Cured and Subsidence Preventing Silicone Encapsulant

作　　者：黄永军 刘金明 陈芳 

机构地区：[1]东莞兆舜有机硅新材料科技有限公司,广东东莞523220

出　　处：《有机硅材料》2015年第1期23-26,共4页Silicone Material

摘　　要：以端乙烯基硅油为基础聚合物、含氢硅油为交联剂、铂乙烯基配合物为催化剂、三氧化二铝为导热填料,添加合适的防沉降剂,制成双组分加成型有机硅灌封胶。研究了锂基膨润土、有机凝胶、气相法白炭黑及炭黑4种防沉降剂对灌封胶在放置过程中的油粉分离程度的影响以及优选材料的后处理工艺。结果表明,这4种防沉降剂对灌封胶都有防沉降作用,但气相法白炭黑的防沉降效果最好;灌封胶中添加5%经六甲基二硅氮烷(质量分数10%)表面处理的气相法白炭黑,能有效阻止导热填料在灌封胶中的快速沉降,与未加气相法白炭黑的样品相比,混合胶料黏度上升6%,B组分沉降物质量减少160%,硫化胶的气泡数量下降230%、拉伸强度提高150%、拉断伸长率提高170%。A two-component molding silicone encapsulant was prepared by vinyl silicone fluid as the base polymer,hydrogen-containing silicone fluid as the crosslinking agent,vinyl platinum complex as the catalyst and alumina as the thermal conductive filler,with the appropriate subsidence preventing agent. In order to reduce the effects of powder and oil separation of the two-component molding addition silicone encapsulant in the process of placing and post-processing,the lithium based bentonite,organic gel,fumed silica and carbon black were added separately,as a subsidence preventing agent. 4 subsidence preventing agents were studied in encapsulant subsidence preventing effect and post-treatment technology of optimizing material conditions.Results suggest that the subsidence preventing agents for encapsulant show anti-sedimentation with the fumed silica subsidence being the best. The two-component molding addition silicone encapsulant with 5% of fumed silica whose surface treated with bistrimethylsilylamine at a mass fraction of 10% effectively prevents the thermal conductive filler in the encapsulant from rapid subsidence. Compared with the fumed-silica-free sample,the viscosity of mixed rubber rises 6%,fallout quality of part B cuts 160% down,the bubble numbers fall by230%,the tensile strength increases by 150%,and the elongation at failure increases by 170%.

关 键 词：有机硅 灌封胶 防沉降剂 锂基膨润土 有机凝胶 气相法白炭黑 炭黑 

分 类 号：TQ433.438[化学工程]