氧化硅与氧化铝填充高硬度硅橡胶

以Wacker R401／70S为基础，通过加入气相二氧化硅或氧化铝获得了高硬度的硅橡胶。研究表明，通过加入气相二氧化硅和氧化铝可以由硬度为70(邵尔A)的硅橡胶制得硬度为90(邵尔A)的硅橡胶，为达到同样的硬度前者比后者的用量小得多，但采用后者作填料时具有更好的热稳定性；采用有机硅烷偶联剂可以显著改善高硬度硅橡胶的机械性能和热稳定性，用有机硅烷偶联剂对无机填料进行处理后再加入硅橡胶，比直接将偶联剂加入硅橡胶效果要好；加入氧化铈可以显著改善高硬度硅橡胶的热稳定性。

High hardness silicone rubber filled with fumed silica or alumina

?High hardness silicone rubber was prepared by addition of fumed silica or alumina on the basis of Wacker R401/70S.Research indicated that the addition of fumed silica or alumina could improve the hardness of silicone rubber from 70(Shore A)to 90(Shore A).Much more alumina were added to achieve the same hardness of silicone rubber as compared with the silica.The silicone rubber stock prepared by the addition of alumina exhibited preferable performance of heat stability.Mechanical properties and heat stability of silicone rubber stock were improved evidently by the addition of silane coupling agents.The performances could be further improved by addition of the additives pretreated with silane coupling agents.The addition of cerium oxide could improve evidently the heat stability of the silicone rubber stock with exceptional hardness.