高低温循环场作用下三元乙丙橡胶结构与性能的变化

Structure and Properties Development of EPDM Aging under Cyclic High-low Temperature

通过ATR-FTIR,超景深显微镜及力学性能、硬度、交联度测试分析,实时追踪了在高低温循环场作用下三元乙丙橡胶(EPDM)的微观结构和宏观性能演变过程。结果表明:在高低温循环场作用下,EPDM的分子链产生断裂降解,同时发生氧化反应,生成OH-、C=O、C-O-C等含氧基团;交联结构增多;试样表面逐渐变得粗糙,直至出现大量裂纹。相应地,随着老化时间增加,EPDM的力学性能下降,硬度增大。循环频率越低,性能劣化速率越快、幅度越大。

The aging behavior of ethylene-propylene-diene monomer rubber（ EPDM） under cyclic high-low temperature was investigated. ATR-FTIR,Super Depth of Field Microscope and degree of crosslinkage were used to explore micro-structure development during the process. It was found that the main change of micro-structure include degradation of molecular,formation of OH-/ C = O / C-O-C,and raise of crosslinkage. The surface of EPDM become roughly,till to a lot of crack,gradually. The tensile property of EPDM decreases and hardness increases with the aging time. Another conclusion is that the lower the frequent of cyclic high-low temperature,the more obviously the mechanical property drops.