以端乙烯基硅油为基础胶、低含氢硅油为交联荆、处理气相法白炭黑为填料、铂-二乙烯基四甲基二硅氧烷配合物为催化剂,制备了加成型室温硫化硅橡胶.考察了端乙烯基硅油黏度、处理气相法白炭黑用量、含氢硅油中的Si-H基与乙烯基硅油中的SiCH-CH2基的量之比(简称A值)对硅橡胶力学特性的影响.结果表明,随着端乙烯基硅油黏度的增加,硅橡胶的拉伸强度、拉断伸长率和撕裂强度分别出现峰值；处理气相法白发黑使硅橡胶的硬度先增后降；较佳工艺为:端乙烯基聚硅氧烷的黏度为5 Pa·s、处理气相法白炭黑用量为25份(按乙烯基硅油用量为100份计)、A值在l～3.6之间.按此条件制成的硅橡胶的邵尔A硬度为34度、拉伸强度4.78～5.09 MPa、撕裂强度4.97 kN/m、拉断伸长率为107％.%The additional room temperature vulcanizing silicone rubber was prepared by using polydime-thyl siloxane terminated by vinyl group as basic components, hydrogen-containing silicone oil as a cross-linking reagent and the complex pound of platinum and divinyltetramethyl disiloxane as catalyst. The effect of the viscosity of basic components, the hydrogen content of hydrogen-containing silicone oil, the filler amount and the A value (the ratio of Si-H/SiCH =CH2 of hydrogen-containing silicone oil and vinyl silicone oil) on the properties of silicone rubber were experimentally examined. Results showed that the tensile strength, the elongation and the tear strength appeared maximum values respectively as the viscosity of basic components was increased. The hardness of the silicone rubber was increased and then decreased with the increase of additional filler. The vulcanized silicone rubber was of excellent mechanical properties while the viscosity of the vinyl silicone oil was 5 Pa·s, and the treatment of fumed silica was about 25 phr ( based on vinyl silicone oil consumption) , and A value was between 1 and 3. 6. Using the above vinyl conditions described a silicone rubber of Shore A hardness of 34 degrees, the tensile strength of 4. 78 ~ 5. 09 Mpa, the tear strength of 4. 97 kN/m and elongation rate of 107 % was obtained.
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