Novel alkylborate-dithiocarbamate lubricant additives: Synthesis and tribophysical characterization
2012 (English)In: Tribology letter, ISSN 1023-8883, E-ISSN 1573-2711, Vol. 45, no 1, 67-78 p.Article in journal (Refereed) Published
Boron-based lubricant additives have recently received significant attention, because of their wear-reducing and frictional properties and low pollution. At the same time, dithiocarbamate complexes with different metals have a long history of being used as multifunctional additives to lubricants. In this study, novel, environmentally friendly additives containing alkylborate and dithiocarbamate groups with alkyl or methylbenzyl substitutes in one molecule were studied. Tribological tests were performed with the additives admixed in a mineral oil using steel-on-steel contacts in a four-ball tribometer. Borate derivatives of different dithiocarbamate ligands were synthesized by several step reactions to investigate tribochemical properties of boron, sulfur, and nitrogen combined in one selected compound. Viscous liquid products were characterized by multinuclear 1H, 13C, and 11B NMR spectroscopy. The surface morphology and the elemental composition of the tribofilms were investigated using an optical profiler and scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS). It was found that some of these novel compounds provide better antiwear performance and similar frictional properties compared with a commercially available ZnDTP package. Traces of sulfur in the tribofilms formed with both 0.2 and 1.0 wt% of alkylborate-dithiocarbamate compounds in a mineral oil were detected with EDS.
Place, publisher, year, edition, pages
2012. Vol. 45, no 1, 67-78 p.
Antiwear additives, Boron, Dibenzyl and diethyl dithiocarbamates, NMR, SEM/EDS, Tribological properties
IdentifiersURN: urn:nbn:se:kth:diva-78957DOI: 10.1007/s11249-011-9855-xISI: 000298646700006ScopusID: 2-s2.0-84855286806OAI: oai:DiVA.org:kth-78957DiVA: diva2:494399
QC 201204032012-02-082012-02-082012-04-03Bibliographically approved