气相法白炭黑对硅橡胶混炼胶性能的影响

Influenceof Fumed Silica on Properties of HTV Silicone Rubber

以甲基乙烯基硅橡胶为基胶,气相法白炭黑为填料,制得硅橡胶混炼胶。研究了气相法白炭黑的比表面积、灼烧减量、吸油值对硅橡胶混炼胶性能的影响。结果表明,随着白炭黑比表面积的增加,硅橡胶混炼胶的拉伸强度增加,拉断伸长率降低;当白炭黑比表面积大于240 m^2/g时,硅橡胶混炼胶易出现结构化;随着白炭黑灼烧减量的增加,硅橡胶混炼胶的拉伸强度增加,拉断伸长率降低,但不明显;当白炭黑灼烧减量超过1.31%时,硅橡胶混炼过程中易出现结构化;吸油值对硅橡胶混炼胶的性能无明显影响,但会影响混炼胶的结构化。选择比表面积210 m^2/g、灼烧减量小于1.31%、吸油值小于1.90 cm^3/g的白炭黑为填料,可获得加工性能良好的硅橡胶混炼胶。

HTV silicone rubber was prepared by MVQ and fumed silica. Influences of fumed silica, such as the specific surface area, calcination reduction and oil absorption value, on the properties of HTV silicone rubber were studied. Results show that the breaking strength of HTV silicone rubber increases as the increas- ing specific surface area of fumed silica, while breaking elongation decreases. The rubber will be structured if specific surface area of fumed silica is more than 240m^ 2/g. As the calcination reduction of fumed silica in-creases, the breaking strength increases,while the breaking elongation decreases unobviously. The rubber will be structured if calcination reduction is over 1.31%. The oil absorption value on the properties of HTV sili- cone rubber is little impact, but it has an affect on the process. The fumed silica whose specific surface area of 210 m^ 2/g, calcination reduction of less than 1.31%, and oil absorption value less than 1.90cm ^3/g, which can obtain HTV silicone rubber with good property.