What are the materials used for rubber soft joints?

What are the materials used for rubber soft joints?
The materials are ordinary natural rubber, EPDM rubber, NBR, etc.
 
If you want to choose different materials, it depends on what kind of medium you are using.
 
Ordinary air, compressed air, water, seawater, hot water, weak acid and strong alkali as well as ordinary natural rubber can be used for this medium with temperature between -20℃ and 115℃. EPDM rubber is a terpolymer of ethylene, propylene and non-conjugated diene hydrocarbons. The main characteristics are superior resistance to oxidation, ozone and erosion, as well as excellent vulcanization properties... Simply put, it is resistant to high temperatures.
 
And NBR is mainly produced by low-temperature emulsion polymerization method, which has excellent oil resistance, high moisture resistance, good heat resistance and strong adhesion. (Oil resistance).