硫化剂种类对EPDM绝热层性能的影响研究

Study on the effect of vulcanizing agent on the performance of EPDM insulation

发动机壳体共固化过程是实现绝热层性能的关键工艺过程。为了优化三元乙丙橡胶(EPDM)绝热层配方性能,科学制定复合材料发动机壳体的共固化工艺制度,提高壳体绝热层成型质量,研究了常用硫化剂种类对EPDM绝热层硫化特性、力学性能、耐热性能和热失重率的影响。结果表明,EPDM/过氧化物体系的起始硫化反应温度较高,硫化速率快,EPDM/硫磺体系的起始硫化反应温度较低,硫化速率较慢;EPDM/过氧化物体系硫化较短时间即可获得较高的力学性能,而EPDM/硫磺体系随着硫化时间逐渐延长,其力学性能呈明显增加趋势;EPDM/过氧化物体系硫化胶片在80℃下的失重率明显高于EPDM/硫磺体系,而且过氧化物的分子结构决定了硫化产物的种类,从而导致不同种类的过氧化物硫化胶片的失重率亦存在较大差别。

The co⁃curing process of solid rocket case was the key process to realize the performance of insulation.In order to op⁃timize the properties of ethylene propylene diene monomer(EPDM)insulation formulation,scientifically establish the co⁃curing process system of composite case,and improve the forming quality of case insulation,the effect of commom vulcanizing agent on the vulcanization characteristics,mechanical properties,heat resistance and thermogravimetric ratio of EPDM insulation were studied in this paper.The results show that the initial vulcanization reaction temperature of EPDM/peroxide system is higher,the vulcanization rate is fast,the initial vulcanization reaction temperature of EPDM/sulfur system is lower,and the vulcanization rate is slower.The mechanical properties of EPDM/peroxide system can be obtained in a short period of curing,while the mechanical properties of EPDM/sulfur system increase significantly with the extension of curing time.The weight loss rate of the vulcanized film with EPDM/peroxide system is significantly higher than that of EPDM/sulfur system at 80℃,and the molecular structure of peroxides determine the type of vulcanization products,which leads to great differences in weight loss rate of different types of peroxide vulcanized film.