The friction and wear behaviors of S-[2-S-(2-hydroxylpropyl)benthiazole]dioctyldithiocarbamic acid ester as additive in liquid paraffin

There has been a growing concern for the use of mineral oils because of the worldwide interest in environmental issues. This has promoted the use of ashless additives as environmental friendly lubricants. A potential ashless additive, S-[2-S-(2-hydroxylpropyl)benthiazole]dioctyldithiocarbamic acid ester, was prepared in this work. The friction and wear behaviors of the synthesized compound as an additive in liquid paraffin were evaluated with a four-ball wear tester. The elemental composition and chemical nature of the antiwear films generated on steel counterface were investigated with electron probe microanalysis (EPMA) and X-ray photoelectron spectroscopy (XPS). It was found that the synthesized additive had excellent antiwear performance. The additive reacted with counterface metal and generated a surface protective film consisting of FeS, organic sulfur compound, FeSO₄, and absorbed compound containing N.