改性废旧硅橡胶复合绝缘子胶粉与三元乙丙橡胶(EPDM)共混物的性能研究

Properties of modified waste silicone rubber composite insulator powder/EPDM blends

采用硅烷偶联剂γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH570)和六亚甲基四胺/氯化铁/氯化亚铁混合物(混合改性剂)分别改性废旧硅橡胶复合绝缘子胶粉,利用衰减全反射傅立叶变换红外光谱(ATR FT-IR)和热失重分析(TGA)表征了KH570改性废胶粉的效果,并将其掺入到三元乙丙橡胶(EPDM)中制备共混物。研究了KH570和混合改性剂改性废胶粉对共混物硫化特性和力学性能的影响,通过扫描电子显微镜对共混物的断面形貌进行了分析,结果表明:经过KH570改性,成功在胶粉表面引入活性反应官能团;KH570和混合改性剂都是废旧硅橡胶复合绝缘子胶粉的有效改性剂,其中填充KH570改性胶粉的共混物在硫化性能和力学性能上均有显著提高,界面相容性也更好;随着废胶粉填充量的增大,共混物的力学性能下降。综合考虑共混物成本与性能关系,KH570改性胶粉的用量为10份时(以总橡胶质量为100份计),共混物的综合力学性能最好。

Waste silicone rubber composite insulator powder was separately modified by using γ-methacryloxypropyltrimethoxysilane （KH570） and a hexamethylene tetramine/iron （ Ⅱ ） dichloride/iron （ Ⅲ ） chloride mixed modifier. The waste powder modified by KH570 was characterized by Fourier transform infrared spectroscopy in the attenuated total reflection mode （ATR FT-IR） and thermogravimetric analysis （TGA）. The modified powder was added to an ethylene propylene diene monomer （EPDM） to prepare EPDM/waste powder blends. The influence of KH570 and mixed modifier modified waste powder on the curing behavior and mechanical properties of the blends was investigated. The fracture surfaces of the blends were characterized by scanning electron microscopy. The results showed that reactive groups were successfully introduced on the surface of the waste powder after modification. Both KH570 and the mixed modifier were found to be effective modifiers for waste silicone rubber composite insulator powder. A greater improvement in the vulcanizing properties, the mechanical properties and the interfacial compatibility were observed for the composites containing the KH570 modified powder. With increasing content of waste powder, the mechanical properties of the blends became poorer. In consideration of the relationship between the cost and the properties of the blends, when the blending ratio of EPDM/KH570 modified waste powder was 90/10 （the total rubber content was 100）, the blend had the optimum mechanical properties.