环氧树脂硫化聚硫醚密封剂的性能研究

以液体聚硫醚橡胶作为密封剂的生胶、环氧树脂(EP)作为硫化剂,成功制备出一种综合性能良好的新型聚硫醚密封剂。结果表明:聚硫醚橡胶的热分解温度(296.4℃)高于聚硫橡胶(281.0℃),热循环后聚硫醚密封剂的拉伸强度变化率或断裂伸长率变化率(31%或42%)均低于聚硫密封剂(45%或64%),说明前者的耐高温性能优于后者;聚硫醚密封剂对多种基材表现出稳定的粘接性能,其常温剥离强度均超过7.5 kN/m(均为内聚破坏),并且其在60℃盐水/航空煤油双层液中浸泡7 d后仍为内聚破坏;聚硫醚密封剂受温湿度影响较小,其硫化速率较大,并且其硫化效果和加工性能良好。

Study on properties of polythioether sealant cured by epoxy resin

With liquid polythioether rubber as crude rubber of sealant,epoxy resin(EP) as curing agent,a new type polythioether sealant with good combination property was successfully prepared.The results showed that the pyrolysis temperature of polythioether rubber(296.4 ℃) was higher than that of polysulfide rubber(281.0 ℃),and the high-temperature resistance of the polythioether sealant was better than that of the polysulfide sealant because after thermal cycling the change rates of tensile strength or elongation at break(31% or 42%) for the former were lower than those for the latter(45% or 64%).The bonded sample between polythioether sealant and numerous materials had steady bonding property,its peeling strength at room temperature was all above 7.5 kN/m(cohesional failure),and the bonded sample which was immersed in two-layer solution based on 60 ℃ brine-aviation kerosene for 7 d was still cohesional failure.And the influences of temperature and humidity on polythioether sealants properties were lesser,the polythioether sealants had higher curing speed,good curing effect and processing properties.