中国胶粘剂

以液态聚硫代醚为生胶,环氧树脂(EP)为硫化剂,制备了一种新型聚硫代醚密封剂。探讨了催化剂种类和EP硫化剂配方对聚硫代醚密封剂的影响,评价了密封剂的低温硫化性能以及低温硫化后的力学性能。研究结果表明:催化剂TMEDA的催化/促进效果最好,对应的EP硫化聚硫代醚密封剂具有最短的活性期;随着多官能度DEN431环氧树脂比例的提高,密封剂的拉伸强度呈先升高后下降的趋势,断裂伸长率却大幅度下降,100%定伸强度和硬度则逐渐提高;在低温环境下,EP硫化聚硫代醚密封剂的硫化速率明显快于MnO2硫化;与常温硫化相比,低温硫化后的力学性能并没有明显变化。

A novel polythiother sealant was prepared by using liquid polythioether as crude rubber and epoxy resin(EP)as vulcanizing agent. The influence of catalyst type and EP vulcanizing agent formula on polythioether sealant was discussed,and the vulcanizing properties at low temperature and the mechanical properties of sealant after low temperature vulcanization were also evaluated. The research results showed that the catalyst TMEDA had the best catalytic/promoting effect,and the corresponding EP-vulcanized polythioether sealant had the shortest active period. With the increase of the proportion of multi-functional DEN431 epoxy resin,the tensile strength of the sealant increased first and then decreased,while the elongation at break decreased significantly,stress at 100%elongation and hardness increased gradually. Under low temperature environment,the vulcanizing rate of EPvulcanized polythioether sealant was much faster than that of MnO2-vulcanized. Compared with normal temperature vulcanization,the mechanical properties after low temperature vulcanization did not change significantly.