Polyalfaolefins (PAO)

Polyalphaolefin appears as a clear, colorless synthetic hydrocarbon fluid with excellent thermal stability and low volatility. Key features include outstanding thermal and oxidative stability, excellent low-temperature properties, very high viscosity index, low volatility, and compatibility with most elastomers and plastics. PAOs are primarily used as synthetic lubricant base stocks for automotive and industrial lubricants, heat transfer fluids, electrical insulating fluids, and as processing aids. 

Alternatives include esters and polyalkylene glycols. Current trends include higher-viscosity grades for specialized applications and versions with enhanced biodegradability profiles. PAOs are classified primarily by low-viscosity grades used in hydraulic fluids and instrument oils, medium-viscosity grades employed in automotive lubricants, and high-viscosity versions utilized in industrial gear oils and specialty greases requiring excellent high-temperature performance and extended service life.