These include M 100 (100% methanol) for buses, M 85 (85% methanol -- 15% by volume gasoline) for specially equipped automobiles, flex-fuel for vehicles equipped to utilize methanol and gasoline blended in any ratio, natural gas, electricity and hydrogen.
The list now includes ASTM Fuel B, 30% toluene/70% iso-octane, representing a normal gasoline without additives; ASTM Fuel C, 50% toluene/50% iso-octane, representing a gasoline with high aromatic content; ASTM Fuel D, 40% toluene/60% iso-octane, representing a medium high aromatic content, used mainly in Europe; M 25, 75% ASTM Fuel C/25% methanol representing a "worst case" gasoline containing methanol as oxygenate; FAM fuel, 50% toluene/30% iso-octane/15% di-isobutylene/5% ethanol, a European test fuel representing an aggressive gasoline; and M 15, 85% FAM fuel/15% methanol, a European test fuel representing a "worst case" gasoline containing methanol as oxygenate.
A hose with an NBR tube and a chloroprene (CR) cover was standard in the automotive industry for both fuel line and fuel filler neck until the mid 1970s and still is used if "sour" gasoline resistance and permeability are not a problem.
ECO vulcanizates soften in peroxidized (or sour) gasoline while NBR vulcanizates harden (ref.
Researchers found that an ECO containing 5% allyl content had improved resistance to peroxidized gasoline, presumably because it was subjected to a combination of degradation and crosslinking (ref.
The initial specifications for peroxidized gasoline resistant NBR were able to be met with appropriately compounded regular (ref.
However, this should not be a problem in practice since gasoline is an excellent plasticizer and hoses are normally wet with fuel.
Data comparing fuel and peroxidized gasoline resistance of compounds based on NBR with 45 and 50% acrylonitrile and a 70/30 NBR/PVC blend based on a 40% acrylonitrile NBR were examined (ref.