以甲基乙烯基硅橡胶为基胶,碳包铝(C-Al)纳米粒子为填料,采用机械混炼法制备了散热用C-Al/硅橡胶复合材料。采用SEM研究了C-Al纳米粒子在硅橡胶中的分散情况;并研究了填料对复合材料热导率、热膨胀系数(CTE)和热稳定性的影响。结果表明:C-Al纳米粒子在硅橡胶中分散性良好;C-Al/硅橡胶复合材料的热导率随C-Al填充量的增加而增大,填充体积分数超过50%时热导率开始下降,C-Al适宜用量为总体积的50%;随着填料的增加,复合材料CTE减小。TGA分析表明,填充C-Al纳米粉体的复合材料热稳定性高于未填充硅橡胶。
With methyl vinyl silicone as the base rubber,filled with carbon coated aluminum(C-Al) nanoparticles,the heat dissipation composites were prepared by using the method of mechanical blending.The SEM was employed to analyze the dispersion of C-Al nanoparticles disperse in silicone rubber which showed that the nanoparticles uniform distribution in silicone rubber.The effect of C-Al nanoparticles on thermal conductivity and coefficient of thermal expansion(CTE) of the silicone rubber were investigated,and it was found that thermal conductivity of the composite increases with increasing the C-Al nanoparticles content,the thermal conductivity begins to decrease when the C-Al volume fraction reaches 50%.The optimum filling amount of C-Al nanoparticles is 50%.The CTE decreases with the loading increasing.TGA shows that the addition of C-Al nanoparticles increases the thermal stability of the silicone rubber.