Gasoline automotive elastomers

Methanol, ethanol, and methy t-butyl ether (MTBE) are blended Into some commercial gasolines. It was Important to determine the effects of such blends on automotive elastomers especially those used In the fuel system. A summary of the results of our studies [1] and detailed data on the effects of methanol/gasollne mixtures on sixteen elastomers [2] have already been published. This paper presents detailed results of our Investigation of the effects of ethanol and MTBE mixtures with gasoline on mechanical and swell properties of automotive elastomers. Comparisons will be made with the effects of methanol/gasollne mixtures on elastomers. Experimental... 

Antioxidants resistant to extraction by lubricants and gasoline are preferred for the stabili2ation of elastomers used in automotive appfications such as gaskets and tubing. Aromatic amine antioxidants, such as A/-phenyl-Ar-(p-toluenesulfonyl)-A-phenylenediamine [100-93-6] (37), with low solubifity in hydrocarbons, are extracted slowly from elastomers and are used for these appfications. 

PBT/elastomer blends display a unique combination of high impact strength, dimensional stability due to their non-hygroscopic namre, excellent resistance to automotive fluids such as gasoline, oils, paint solvent, aqueous salt solutions and good heat resistance. In addition, their easy processability (low melt viscosities) lends... 

MTBE is a colorless, low-viscosity liquid with characteristic terpene-like odor. It is flammable and nonautoxidizable. It is miscible in all proportions with gasoline, scarcely soluble in water, and presents no phase-separation problems in existing distribution systems. It is stable in storage and has no extreme effect on automotive fuel elastomers and plastics at the commercial levels used. 

Experience gained from the observation of oil seals in the automotive industry indicated that blends of methanol and gasoline can have a deleterious effect on many elastomers currently used in automotive oil seals. The effect of methanol as a constituent (15%) in an aromatic fuel is greater than that of other higher alcohols, e.g. ethanol, as is shown in Fig. 7. This should be compared with the swelling behaviour of the same range of elastomers in pure 42% aromatic fuel (Fig. 8). ... 

Fuel cells will soon be a viable alternative to the gasoline-powered internal combustion engine, and, beyond 2010, they can be expected to be the primary automotive power source. Buses are fuel cell-powered, and cars are next. A motivation driving fuel cell development for automotives is tougher emission standards required in several eastern states and California. Another motivation is to enhance national security with energy independence. U. S. automobile manufacturers plan to have fuel cell-powered cars on the market by 2004. Thermoplastic elastomers coated with a platinum catalyst compose the fuel cell membrane electrode, referred to in Sec. 10.3.1.3. 

Petroleum is the world s primary source of energy and petrochemical feedstock. Although crude oil has few uses, it is refined to produce gasoline, jet fuel, industrial and domestic fuel oil, kerosene, solvents, and diesel fuel, as well as feedstocks such as ethylene, propylene, butenes, isoprene, and butadiene. These feedstocks form the basis of production of elastomers, plastics, and artificial fibers. In the USA, " 41% of refinery yield is automotive and aviation gasoline (Hoffman, 1982). Fuel oil is the next... 

Then a new technique was developed - known as catalytic cracking - and before long there was an abundance of the petrochemicals needed for elastomers, plastics, and synthetic fibers. Ethylene dominates all the other petroleum building blocks and one of its first uses was as ethylene glycol, the antifreeze used in cars. Another automotive-associated use was tetra-ethyl lead (TEL), a gasoline additive to reduce engine knock and increase fuel efficiency. 

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