硅烷偶联剂改性碳酸钙对室温硫化硅橡胶密封胶的性能影响

采用硅烷偶联剂对超细CaCO3进行表面改性制备室温硫化(RTV)单组分硅橡胶密封胶,讨论了偶联剂的种类、用量及其表面改性方式对该密封胶性能的影响。研究结果表明,采用硅烷偶联剂事先对CaCO3进行表面处理的改性方法较好;其中用巯丙基三甲氧基硅烷偶联剂(A-189)处理的CaCO3对密封胶的增强效果较好(其拉伸强度为0.57 MPa、最大强度伸长率为159.60%),但脱模时间需要5 d,存在着明显的延迟硫化现象;用3-缩水甘油醚氧基丙基甲基二乙氧基硅烷偶联剂(KBE-402)处理的CaCO3对密封胶的增强效果(其拉伸强度为0.60 MPa,最大强度伸长率为105.00%)优于3-缩水甘油醚氧基丙基三甲氧基硅烷偶联剂(KBM-403)。

Effect of CaCO3 modified by silane coupler on RTV silicone sealant performance

The one component RTV silicone sealant was prepared by silane coupler as surface modifier of superfine CaCO3.The influences of kinds,content and surface modified ways of silane coupler were discussed on the sealant performance.The research results showed that the modified methods of CaCO3 surface prior treated by silane coupler was better.Thereinto the enhancement effect of CaCO3 treated by A-189(the tensile strength was 0.57 MPa,elongation ratio in maximum strength was 159.60%) on sealant performance was better,but the sealant has phenomenon of obvious delay vulcanization because demoulding time need 5 days.The enhancement effect of CaCO3 treated by KBE-402(the tensile strength was 0.60 MPa,elongation ratio in maximum strength was 105.00%) on sealant performance was better than by KBM-403.