A study of S-[2-(2-hydroxygenacetyl)thiobenzothiazo-1-yl]dialkyldithiophosphates as novel additives in liquid paraffin

Three S-[2-(2-hydroxygenacetyl)thiobenzothiazol-1-yl]dialkyldithiophosphate s were synthesized and their wear and friction behaviors as additives in li quid paraffin were evaluated using a four-ball tester. The thermal degradat ion tests were conducted to identify their thermal stable properties using thermogravimetry analyzer (TGA) in a Perkin-Elmer model 7 thermal analyzer. The protective film formed on the rubbed surface was investigated by X-ray photoelectron spectroscopy (XPS). Based on the experimental results, the n ovel additives showed good antiwear ability and friction-reducing propertie s. The thermal stable properties of three compounds show that the longer th e alkyl chain, the more stable. The results of XPS analyses illustrate that the prepared compound as additive in liquid paraffin forms a protective fi lm containing ferric sulfide, ferric sulfate, othophosphate and compounds c ontaining sulfur and nitrogen on the rubbed surface. (C) 2000 Elsevier Scie nce S.A. All rights reserved.