Chemical modification of vegetable oils for the production of biolubricants using trimethylolpropane: A review

Lubricating oil producers are shifting attention toward the use of renewable and biodegradable energy sources for the production of lubricating oils. This is necessitated by the depleting mineral based energy sources and the negative impact of continuous usage of engine oils from fossil sources. Biomass sources are cheap, environmentally friendly, and offer a good alternative to the conventional mineral oil sources. Biolubricants provide lubricity for two moving-surfaces in contact. They are essential for heat transfers, power transmissions, lubrication, and corrosion inhibition in machinery. However, the use of biolubricating oils are associated with challenges such as poorer low temperature properties and poor oxidative stability during usage. Chemical modification of vegetable oils with polyols has been explored as a potential source for biolubricant synthesis and production. This paper provides a concise review of the use of trimethylolpropane (TMP) as the polyol used for chemically-modified biolubricants using vegetable oils as base stocks. TMP improves the physicochemical properties of biolubricants and enhances the thermo-oxidative stability of the biolubricants.