A. Schwab, W. Rohwedder, J. S. Ard
Dec 1, 1979
Citations
0
Influential Citations
5
Citations
Journal
Phosphorus Sulfur and Silicon and The Related Elements
Abstract
Abstract Model compounds prepared for evaluation as extreme pressure lubricant additives were studied by mass, nuclear magnetic resonance, and Raman spectroscopy. Mass spectral studies showed strong molecular ions upon electron impact of octadecyl sulfide and disulfide. Both sulfur-sulfur and carbon-sulfur cleavages were noted for octadecyl disulfide and tetrasulfide. With octadecyl tetrasulfide the molecular ion appears to lose sulfur even at 15 eV; this sulfur loss was not observed with octadecyl sulfide and disulfide. From nuclear magnetic resonance measurements it was noted that a chemical shift downfield occurs for the α-methylene protons with increasing length of the sulfur moiety. Raman spectra showed strong peaks attributed to S-S stretching. For octadecyl disulfide these peaks occurred at 510 and 526 cm−1 (solid state) and for octadecyl tetrasulfide peaks were found at 432 and 488 cm−1 (solid state) and 437 and 488 cm−1 (liquid state, undiluted as a melt at 58°). All have weak peaks between 625 a...