Synthesis And Characterization Of Estolide Esters For Tribological Properties
The development of vegetable oil based resources with eco-friendly and sustainable alternatives have encouraged replacing petroleum based resources. Our study envisages on synthesis of estolide from ricinoleic acid and different saturated fatty acids through improvement in its lubrication properties. These reactions were conducted under vacuum at 60°C for 24 h without solvent and different acid catalyst such as NH2SO3H and CH3SO3H. The hydroxy site on the ricinoleic acid makes it a suitable site for esterification with saturated fatty acids yield estolide, which shows superior low temperature properties i.e. pour point from -25 to -15°C and viscosity index ranged from 150 to 198. As the synthesized estolide products are vegetable oil based lubricants they are biodegradable and show superior low temperature properties, viscosity index as well as comparable cost to petroleum oils which will widely acceptable in the marketplace. Solvent free and use of sulphamic acid, which is green and noncorrosive material supports the prospects of commercialization of estolide-ricinoleic based biolubricants.