Advanced Characterization of Estolides from Coconut, Sunflower and Karanja Oils

Abstract

Cold flow properties of vegetable oils are generally subpar to industrial lubricants. This is one major drawback that limits the usage of otherwise abundant vegetable oil. Estolides belong to the class of esters synthesis from naturally occurring oils as carboxylic acid functionality of a fatty acid reacts, forming ester linkage on an unsaturated site of another fatty acid. Estolide number tells the mean number of fatty acids attached to the base fatty acid that varies with respect to synthesis temperature, reacting saturated fatty acids, and other parameters. Though vegetable oils show excellent biodegradability, their cold flow properties are poor compared to functional lubricants. In this present study, three vegetable oils have been synthesized to obtain their estolides, they are coconut, sunflower, and karanja oils to analyze the variations. Lubricating machines with mineral-based lubricants have become a major cause of pollution now. To use natural oils for making lubricants instead of petroleum is something mainstream researchers have been looking at for a few decades. Though vegetable oils show excellent biodegradability, their cold flow properties are poor compared to functional lubricants. Biodegradable lubricant oils must have excellent cold flow properties as well as competitive costs in order to be accepted widely as a base stock for industrial lubricants.