This content is not included in
your SAE MOBILUS subscription, or you are not logged in.
Aggregation Behavior of Common Motor Oil Additives
Annotation ability available
Sector:
Language:
English
Abstract
The aggregation behavior of three common motor oil additives, calcium dinonylnaphthalene sulfonate (CaDNNS), zinc dinonyldithiophosphate (ZDDP) and polyisobutenyl succinimide of tetraethylene pentamine (PIB-TEPA) in n-decane were examined using light scattering, osmometry and viscometry techniques. The experimental data were analyzed using two phenomenological models of association, the continuous association model which assumes the coexistence of aggregates of all sizes including the monomers, and the closed association model which assumes the coexistence of aggregates of only a single size with the monomers. The closed association model was found to describe the experimental data well for CaDNNS and PIB-TEPA while both association models fitted the data for ZDDP comparably, but somewhat poorly. The analysis of experimental data led to the conclusion that CaDNNS micelles were composed of 13 and 11 monomers, PIB-TEPA micelles had 19 and 9 monomers, and ZDDP aggregates had 4 and 3 monomers, at 25°C and 65°C, respectively. At 25°C, the CaDNNS and the ZDDP aggregates were ellipsoidal in shape and it was not possible to discriminate between oblate and prolate ellipsoids. The micelle sizes assuming both shapes have been estimated. The PIB-TEPA micelle was spherical with a diameter of 6.4 nm. For all three additives, the solutions were dominated by aggregates at solute concentrations larger than 0.02 gm/cm3 (20 kg/m3), while below this concentration, the presence of non-aggregated monomers was important to account for.
Recommended Content
Technical Paper | OCTANES FROM MOTOR OILS |
Technical Paper | VOCs evaporation rate from a poly(vinyl chloride) matrix and its impact over interior's atmospheric composition |
Authors
Topic
Citation
Ganc, J. and Nagarajan, R., "Aggregation Behavior of Common Motor Oil Additives," SAE Technical Paper 912397, 1991, https://doi.org/10.4271/912397.Also In
References
- Smalheer C.V. “Additives,” in Interdisciplinary Approach to Liquid Lubricant Technology A NASA Symposium I 1972
- CRC Handbook of Lubrication Booser E.R. II CRC Press Boca Raton, Florida 1984
- Inoue K. Watanabe H. “Interactions of Engine Oil Additives,” ASLE Trans. 26 189 1982
- Rounds F.G. “Additive Interactions and Their Effect on the Performance of a Zinc Dialkyl Dithiophosphate,” ASLE Trans. 21 91 1978
- Hsu S.M. Lin R.S. “Interactions of Additives and Lubricating Base Oils,” SAE SP 558 61 Society of Automotive Engineers Warrandale, PA 1983
- Hsu S.M. Ku C.S. Lin R.S. “Relationship Between Lubricating Basestock Composition and the Effects of Additives on Oxidation Stability,” SAE SP 526 29 Society of Automotive Engineers Warransdale, PA 1982
- Kertes A.S. Gutmann H. “The Physical Chemistry of Aggregation and Micellization,” in Surface and Colloid Science 8 Matijevic E. Wiley, New York 1976
- Ganc J.R. “A Study of the Aggregation and Micellar Behavior of Three Common Motor Oil Additives,” Department of Chemical Engineering, The Pennsylvania State University University Park, PA 1990
- Nagarajan R. “Molecular Theory for Mixed Micelles,” Langmuir 1 331 1985
- Nagarajan R. Ganesh K. “Block Copolymer Self-Assembly in Selective Solvents,” J. Chem. Phys. 90 1989
- Bauer N. Lewin S.Z. “Determination of Density,” Techniques of Organique Chemistry 2nd 1 Weissberg A. Interscience Inc. New York 1959
- Shoemaker D.P. Garland C.W. Steinfeld J.I. Nibler J.W. Experiments in Physical Chemistry 4th McGraw-Hill New York 1981
- Kaye W. McDaniel J.B. Applied Optics 13 1974
- Matheson R.R. “Viscosity of Solutions of Rigid Rodlike Macromolecules,” Macromolecules 13 643 1980
- Einstein A. Investigations on the Theory of Brownian Movement Dover Publications New York 1956
- Simha R. J. Phys. Chem. 44 25 1940
- Kuhn W. Kuhn H. Helv. Chim. Acta 28 97 1945