Polyisobutenes (PIBs) are non-drying synthetic hydrocarbon polymers made from the polymerization of olefins. PIBs are used in a wide range of applications including greases, forming lubricants, sealants, inks, coatings, paint, liquid colorants for plastics, agriculture, cling film, and hot melt & PSA adhesives. They can be used as Group V base oils in synthetic lubricants or as intermediates for the production of lubricant additives. Many look to PIBs as an economical replacement for bright stock, as they are readily available and less expensive than PAOs and PAGs. API Group I base oil production has fallen in recent years, and is expected to continue to decline, leaving many looking for suitable replacements.
Meanwhile, PIB capacity has increased about 30 percent since 2012 and is expected to continue to increase in the coming years. Demand is not expected to grow as quickly as supply, which means cost and availability should remain fairly stable. Lubricants currently account for 60 percent of PIB demand.
In lubricants, PIBs are commonly used as in intermediate in the production of dispersants. The can also be used as viscosity index improvers or anti-mist agents for metalworking fluids. As a high-viscosity base oil, PIBs find use in gear oils, grease, marine oil, and two-stroke engine oils. They are attractive as bright stock replacement due to their solubility in mineral oil and the fact that they burn cleanly without producing “blue smoke”. PIBs also display a number of good properties including high viscosity indices, low pour points, excellent high temperature properties, and good lubricity. The also meet the requirements for food contact applications as defined by the U.S. Food and Drug Administration (FDA) in title 21 Code of Federal Regulations 177.1430, making them useful for food grade lubricants as well.