多苯基聚硅氧烷对硅橡胶阻尼性能的影响

以低苯基硅橡胶为基胶，通过添加多苯基聚硅氧烷，制备出阻尼硅橡胶，并对其性能进行了研究。结果表明，加入铂催化的多苯基聚硅氧烷能显著提高硅橡胶在-50-150℃温度区域内的阻尼系数；多苯基聚硅氧烷中侧基数量越多，阻尼系数峰值出现的温度越高。加入铂催化的多苯基聚硅氧烷能够显著提高硅橡胶的撕裂强度和断裂伸长率，对硅橡胶的拉伸强度和热稳定性影响不大。两种催化体系合成的多苯基聚硅氧烷对硅橡胶阻尼系数的影响不同，Ph3SiO-接枝率较低时，加入锡催化剂多苯基聚硅氧烷的硅橡胶的阻尼峰值较高；接枝率进一步增加时，加入铂催化多苯基聚硅氧烷的硅橡胶的阻尼系数曲线出现尖峰，而加入锡催化剂多苯基聚硅氧烷的硅橡胶的阻尼峰仍呈现宽峰。

Effect of Modified Polysiloxane on Damping Properties of Silicone Rubber

The damping silicone rubbers were prepared with low phenyl silicone rubber as basic gel via adding phenyl polysiloxane, and the properties of these rubbers were analyzed. Result showed that modified polysiloxane significantly increased the damping property of the silicone rubber at room temperature as well as as its tear strength and elongation at break. Meanwhile, adding phenyl polysiloxane has little effect on the ten- sile strength of the silicone rubber. It also showed that modified polysiloxane with larger ratio of grafted groups had better damping performances and higher temperature of the peak value of tanS. The molecular size distri- butions of modified polysiloxane also impacted the damping property of silicone rubber due to verified sizes of motion units.