Seeking information on the properties of different rubber materials

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Nitrile rubber is used to manufacture skeleton oil seals, suitable for general oil resistance requirements. The temperature resistance rating is basically below 130°C. If the oil that can be used is relatively simple, such as ordinary engine oil or lubricating oil, there is no problem. Of course, for other media, it depends on the specific performance requirements. EPDM cannot be used to manufacture skeleton oil seals; it has poor adhesion to metals, and it is not resistant to oils either, so there is no need to consider using it for making oil seals. They are mainly used as simple gasket materials. Of course, due to its oil resistance, it is generally used for sealing in environments such as water, steam, acids, and alkalis. This is what chemistry refers to as like dissolves like. Oil seals made of fluororubber inherently have a high temperature resistance rating. For temperatures above 150°C, fluororubber is generally considered for manufacturing oil seals. Of course, in terms of resistance to ordinary oils, fluororubber is inferior to nitrile rubber; however, when it comes to complex oils, fluororubber performs better than nitrile rubber. Therefore, fluororubber can be used in more demanding environments. The components of the same type of rubber compound are generally similar, but the purity of the compound and the uniformity of its molecular weight distribution vary. Additionally, the vulcanization systems used by different companies differ, which is why rubber compounds of the same type from different companies can exhibit differences. For the companies that lead in this type of adhesive, their advantages will be even more pronounced.

Then for the liquid in PH6, since it’s not oil, nitrile rubber would be suitable.

With PH=6, it is a weak acid; oil resistance need not be considered, and EPDM can be used. But it cannot be used as an oil seal.