Effects of cure system and filler on chemical aging behavior of fluoroelastomer in simulated proton exchange membrane fuel cell environment

The chemical aging behavior of gaskets especially the chemical stability is crucial to the overall performance of PEMFC stack. The chemical stability of gaskets not only depends on the polymer but also heavily depends on the other ingredients. In this paper, we have studied the properties of fluoroelastomer with different amount of the cure agent, acid-acceptor and filler in the simulated PEMFC environment. The weight and volume change of samples was monitored. The surface conditions of the virgin and aged samples were observed using optical microscopy. Leachants in the soaking solution were detected using atomic emission spectrometry. ATR-FTIR was employed to determine the chemical change of samples. These results show that FKM cured with bisphenol system has the best comprehensive properties when the amount of bisphenol AF is set as 2.5 phr and the amount of Ca(OH)2 is 6 phr. The inert filler BaSO4 is not suitable for FKM because it has inferior effect on the compression resistance and chemical stability of FKM in this system.