空间级加成型双组分导热硅橡胶的研制

Preparation of Two-component Space-grade Addition Cure Thermal Conductive Silicone Rubber

以乙烯基硅油、含氢硅油、导热填料、铂催化剂为原料,制成了空间级加成型双组分导热硅橡胶。研究了精制方法对乙烯基硅油真空质量损失率的影响以及填料种类、用量对硅橡胶性能的影响。结果表明,采用溶剂萃取法精制乙烯基硅油,可使乙烯基硅油的真空质量损失率降至0.47%,满足空间级材料的使用要求;硅橡胶的较佳配方是：黏度5 000 m Pa·s的乙烯基硅油100份,粒径5～8μm的碳化硅240份,交联剂5份;在此条件下制得的加成型双组分导热硅橡胶的热导率为1.26 W/m·K、接触热导率在15 000 W/m^2·K以上、拉伸强度为1.68 MPa、真空质量损失率为0.27%、可凝挥发物质量分数为0.02%,

The two-component space-grade addition cure thermal conductive silicone rubber was prepared with vinyl silicone oil,thermal-conductive filler,Pt catalyst and methyl hydro-silicone oil as the basic materials. The purifying method,types and contents of the fillers were discussed on the vacuum mass loss of vinyl silicone oil. Results showed that the total mass loss（ TML） of the polysiloxane extracted by n-hexane / alcohol component solvent was 0. 47%,which could meet the requirement of NASA. The silicone rubber was made by100 phr of hydro-silicone oil with viscosity of 5 000 m Pa·s,240 phr of silicon carbide with particle size of 5 ～8 μm,and 5 phr of crosslinking agent. Thus,the silicone rubber with Si C had the thermal conductivity of 1.26 W / m·K,contact heat-conduction coefficient above 15 000 W / m2·K,tensile strength of 1. 68 MPa,TML of0. 27%,and mass fraction of CVCM was 0. 02%.