Hydrin is an advanced synthetic rubber that has similar properties to Nitrile, but with better resistance to heat, and hydrocarbon oils and fuels. For this reason, it is commonly used in applications where a little higher temperature capability than Nitrile is needed.
Hydrin’s excellent resistance to hydrocarbon fluids and fuels make it ideal for air intake systems incorporating exhaust gas recirculation or engines with moderate to high levels of blow-by products. It is popularly used in automotive clean air intake ducts because of its performance at broad temperature ranges (-60F / 275F).
It is a good substitute for Butyl rubber when gas permeability and oil resistance is needed.
Hydrin does have a few limitations as its compression set is ‘fair’ while at higher temperatures. Also, it does not respond well to brake fluid.