混合动力汽车引擎用高导热环氧灌封胶的研制

Preparation of Epoxy Sealants with High Thermal Conductivity Used for Hybrid Electric Vehicle Engines

采用环氧为基体树脂,α_Al2O3为填料研制了一种适用于大型工件的高导热灌封胶,分析了环氧树脂种类、固化剂及促进剂用量、粉体种类及用量、后固化条件等因素对灌封胶性能的影响。应用结果表明：高导热灌封胶的主要性能优于国外同类产品：物料粘度小,110℃下的可使用期达1 h,便于大型工件的真空脱泡及灌封操作;固化物导热系数达1.34 W/（m.K）;固化收缩率不超过0.35%;25~160℃的线膨胀系数为27×10-6K-1;热变形温度为158℃;具有优良的耐冷热冲击和抗开裂能力。

A kind of thermal conductive sealent fitting for large work pieces was prepared by using epoxy resin as matrix and α-Al2O3 as filler.The effect of epoxy resin type,dosage of curing agent and promoting reagent,type and amount of powder filler,post curing condition on the properties of the sealents were investigated.Sealents with high thermal conductivity were obtained by formula optimization,the main key properties of which are better than that of similar foreign products： much lower viscosity of the material before curing,retaining excellent fluidity at 110 ℃ for 1 h,especially convenient for vacuum deaeration and casting operations for large work pieces;thermalconductivity of the cured product reaches to 1.34 W/（m·K）;curing shrinkage not more than0.35%;linear expansion coefficient only 27×10-6 K-1 from 25 ℃ to 160 ℃;heat distortion temperature 158 ℃;and has excellent resistance to heat shock and anti-cracking ability.