氢氧化铝粒径及添加量对硅橡胶性能的影响

Effects of particle size and amount of aluminum hydroxide on properties of silicon rubber

考察了在硅橡胶中添加氢氧化铝的粒径和添加量对其力学性能、电性能、阻燃性能、憎水性及耐热老化性能等的影响。结果表明,粒径1.2μm的氢氧化铝不易分散,在硅橡胶中的分布不均匀;为满足硅橡胶的漏电起痕和阻燃性能,氢氧化铝添加量应在115份(质量,下同)以上。硅橡胶的拉伸强度和撕裂强度均随氢氧化铝添加量的增加而先增大后减小,门尼黏度随添加量增加逐渐增大,而氢氧化铝粒径和添加量对其体积电阻率和表面电阻率都没有明显的影响。综合技术和经济因素考虑,以在硅橡胶中添加粒径2.6μm、添加量135份的氢氧化铝为宜。

The effects of particle size and amount of aluminum hydroxide on mechanical properties,electrical properties,flame retardancy,hydrophobi-city and heat aging resistance of silicone rubber were investigated.The results showed that the aluminum hydroxide with particle size of 1.2μm was not easy to disperse and was not evenly distributed in silicon rubber.In order to meet the leakage and flame retardancy of silicone rubber,the addition amount of aluminum hydroxide should be more than 115 phr(mass,the same below).The tensile strength and tear strength of silicone rubber first increased and then decreased with increase of aluminum hydroxide amount,and the Mooney viscosity gradually increased,but the particle size and amount of aluminum hydroxide had no obvious effect on the vo-lume resistivity and surface resistivity.Considering technical and economic factors,it was suitable to select 135 phr aluminum hydroxide with particle size of 2.6μm for the preparation of silicone rubber.