ABSTRACT
Polyalkylene glycols (PAG) were one of the first synthetic lubricant base fluids to be developed and commercialized. In the early 1950s, PAG formulated automotive crankcase engine lubricants were developed and significant trials were conducted in many states in the United States. The molecular weight and thereby the viscosity of a PAG base fluid can be controlled within narrow limits. The most common PAG base oils used today are random copolymers of ethylene oxide and 1,2-propylene oxide. The versatility of PAG chemistry means a broad range of molecular weights and viscosities can be manufactured. The use of PAGs in industrial gear lubricants continues to grow with key benefits being outstanding gear efficiency, excellent load carrying capability, and long oil drain intervals. PAG lubricants have been used in air-cooled two-stroke cycle engines. Their clean burn-off characteristics virtually eliminate engine problems related to spark plug fouling, exhaust port plugging, and combustion chamber deposits.
