Esters of petroselinic acid containing Trachyspermum copticum seed oil: Potential industrial lubricant base stocks.

Trachyspermum copticum seed oil contains volatile oil rich in thymol, which is distilled out and used for medicinal and
aromatic formulations. The seed powder after removal of the volatiles loses its importance. However, the fixed oil being rich
in unsaturation with petroselinic acid (18:1, Δ6; 68.3%) and linoleic acid (18:2; 25.3%) is used for preparing biolubricant
base stocks. Methyl, isopropyl and 2-ethyl hexyl esters of the oil have been converted to epoxides, followed by in situ
hydroxylation and acylation using hexanoic and butyric anhydrides. The acylated products have been evaluated for lubricant
properties, and are found to exhibit density (0.91-0.97 g/cc); viscosity of 23.5-27.3 cSt at 40°C and 4.85-5.33 cSt at 100°C.
The values are comparable to jatropha acylated products. The products exhibited good copper corrosion resistance value of
‘1a’ and high flash points of 230-242°C. The acylated esters with good weld load behavior, and lower wear and pour point
values and viscosity indices, 128.84-138.94, can be potential base stocks belonging to group III category lubricants with ISO
VG Grade about 22. These products can be further explored for the preparation of hydraulic, metal working and other
industrial fluid formulations.