Study of cystine schiff base esters as new environmentally benign multifunctional biolubricant additives

Two additives CySBE-A and B were prepared via a two step synthesis. First, the cystine schiff base (CySB) was synthesized utilizing 3,5-di-t-butyl-4-hydroxybenzaldehyde. In the second step, its esterification with lauroyl alcohol and 2-ethyl hexanol results the final products CySBE-A and B respectively. Both additives were evaluated as multifunctional additive in polyol base oil for antioxidant, antifriction, antiwear and anticorrosion property. Universal oxidation test (IP-306) was used for evaluating antioxidant property. Antifriction and antiwear properties in terms of average friction coefficient and wear scar diameter (WSD) were evaluated using four ball test. The CySBE-A was found to be effective than CySBE-B.

Graphical abstractThe graphics shows experimental setup of the four ball test which was used for the evaluation of the antiwear and antifriction property of the synthesized additives. The decreased average friction coefficient in the case of ACySB-A is also shown along with its molecular structure.Figure optionsDownload full-size imageDownload as PowerPoint slide