The Use of Toluene/Isooctane/Alcohol Blends to Simulate the Swelling Behavior of Rubbers in Gasoline/Alcohol Fuels

The volume increase of fuel handling rubbers in gasoline/alcohol blends can be simulated with considerable accuracy by using appropriate blends of toluene/isooctane/alcohol. This was achieved by allowing toluene to represent the aromatic content of the gasoline blend, isooctane the combined paraffinic, naphthenic and olefinic contents, and by matching the alcohol concentrations. The swelling behavior of fluorohydrocarbon, fluorosilicone, nitrile and epichlorohydrin rubbers has been characterized by total immersion in a wide blend range of toluene/isooctane/alcohol and in toluene/isooctane/methyl tert.-butyl ether.