Investigation on the Potential of Dextrose, Sucrose and Cellulose Dodecenylsuccinate Esters as Lubricity Additive

As a consequence of the environmental issues and the increasing global demand of the lubricants, we need to have the sustainable raw material sources not only for the lube base oil but also for additives. In view of this, we have synthesized the dodecenylsuccinate (DDSA) ester of dextrose (sample 1), sucrose (sample 2) and cellulose (sample 6) with almost same degree of substitution (DS ~2.0). The lubricity was observed for these synthesized samples in n-decane which was taken as lubricant reference base fluid. The lubricity tests were carried out as per the ASTM D6079 using high frequency reciprocating test rig. It was observed that the dextrose-DDSA ester shows good lubricity properties in comparison to sucrose and cellulose. 1 % sucrose-DDSA in n-decane has decreased the value of wear scar diameter from 800 to 515 µm while the values for sucrose-DDSA and cellulose-DDSA were found to be 565 and 590 µm respectively. Further, to see the effect of varying DS over the lubricity in the case of cellulose-DDSA esters, the four cellulose ester samples (sample 3–6) with varying DS (0.68, 0.95, 1.43 and 2.03) were prepared and evaluated. It was also observed that the lubricity increases with the increasing DS value in cellulose-DDSA esters.