Friction and Wear Protection Performance of Synthetic Siloxane Lubricants


Several new siloxane lubricants were synthesized with linear and ring-shaped branch structures of various lengths and branch contents, aiming at a search for better molecular design for lower boundary friction and more effective surface protection against wear of materials. Their molecular structure and mass were measured by means of nuclear magnetic resonance and gel permeation chromatography, respectively. The new lubricants were compared with commercially available polysiloxanes, poly-α-olefins, and perfluoropolyether in lubricating a steel ball-on-steel disk interface using a tribotester at a load of 1.76 GPa and an entrainment speed of 0.025 m/s. The results are used to explain the effects of alkyl branch length L, pendant type J, percent of branch functional monomers Q, and degree of polymerization DP on siloxane design for the most effective boundary lubrication.

This is a preview of subscription content, access via your institution.

Fig. 1
Fig. 2
Fig. 3
Fig. 4
Fig. 5
Fig. 6
Fig. 7
Fig. 8
Fig. 9
Fig. 10
Fig. 11


  1. 1.

    Ziegler, M., Fearon, F.: Silicon-Based Polymer Science: A Comprehensive Resource. American Chemical Society, Washington DC (1990)

    Google Scholar 

  2. 2.

    Rochow, E.: Silicon and Silicones. Springer, Berlin (1987)

    Book  Google Scholar 

  3. 3.

    De Jaeger, R., Gleria, M.: Silicon-Based Inorganic Polymers. Nova Science Publishers Inc., New York (2008)

    Google Scholar 

  4. 4.

    Baker, E., Barry, A., Hunter, M.: Dielectric constants of dimethyl siloxane polymers. Ind. Eng. Chem. 38, 1117–1120 (1946)

    Article  CAS  Google Scholar 

  5. 5.

    Brophy, J.E., Militz, R.O., Zisman, W.A.: Dimethyl-silicone-polymer fluids and their performance characteristics in unilaterally loaded journal bearings. Trans. ASME 68, 355–360 (1946)

    CAS  Google Scholar 

  6. 6.

    Hunter, M., Warrick, E., Hyde, J., Currie, C.: Organosilicon polymers. II. The open chain dimethylsiloxanes with trimethylsiloxy end groups1. J. Am. Chem. Soc. 68, 2284–2290 (1946)

    Article  CAS  Google Scholar 

  7. 7.

    Hurd, C.: Studies on siloxanes. I. The specific volume and viscosity in relation to temperature and constitution. J. Am. Chem. Soc. 68, 364–370 (1946)

    Article  CAS  Google Scholar 

  8. 8.

    Patnode, W., Wilcock, D.: Methylpolysiloxanes1. J. Am. Chem. Soc. 68, 358–363 (1946)

    Article  CAS  Google Scholar 

  9. 9.

    Sauer, R.O., Mead, D.J.: Dipole moments of linear and cyclic polymethylpolysiloxanes. J. Am. Chem. Soc. 68, 1794–1797 (1946)

    Article  CAS  Google Scholar 

  10. 10.

    Dickens, P., Sullivan, J., Lancaster, J.: Speed effects on the dry and lubricated wear of polymers. Wear 112, 273–289 (1986)

    Article  CAS  Google Scholar 

  11. 11.

    Wilcock, D.: Vapor pressure-viscosity relations in methylpolysiloxanes. J. Am. Chem. Soc. 68, 691–696 (1946)

    Article  CAS  Google Scholar 

  12. 12.

    Fox, H., Taylor, P., Zisman, W.: Polyorganosiloxanes… surface active properties. Ind. Eng. Chem. 39, 1401–1409 (1947)

    Article  CAS  Google Scholar 

  13. 13.

    Lewis, G.: The atom and the molecule. J. Am. Chem. Soc. 38, 762–785 (1916)

    Article  CAS  Google Scholar 

  14. 14.

    Flory, P.: Statistical Mechanics of Chain Molecules. Interscience, New York (1969)

    Google Scholar 

  15. 15.

    Brandup, J., Immergut, E., Grulke, E.: Polymer Handbook. Interscience, New York (1975)

    Google Scholar 

  16. 16.

    Tabor, D., Willis, R.: Thin film lubrication with substituted silicones: the role of physical and chemical factors. Wear 11, 145–162 (1968)

    Article  CAS  Google Scholar 

  17. 17.

    Tabor, D., Willis, R.: The formation of silicone polymer films on metal surfaces at high temperatures and their boundary lubricating properties. Wear 13, 413–442 (1969)

    Article  CAS  Google Scholar 

  18. 18.

    Jemmett, A.: Chemical behaviour of siloxanes at metal interfaces. Tribology 1, 173–177 (1968)

    Article  Google Scholar 

  19. 19.

    Jemmett, A.: Chemical behaviour of siloxanes at metal interfaces-2. Tribology 1, 237–239 (1968)

    Article  Google Scholar 

  20. 20.

    Jemmett, A.: Review of recent silicone work. Wear 15, 143–148 (1970)

    Article  CAS  Google Scholar 

  21. 21.

    Willis, R., Shaw, R.: The thermal oxidative decomposition of polyorganosiloxane fluids at metal surfaces. J. Colloid Interface Sci. 31, 397–423 (1969)

    Article  CAS  Google Scholar 

  22. 22.

    Willis, R.: Thermal decomposition of silicone fluids at metal surfaces. Nature 221, 1134–1135 (1969)

    Article  CAS  Google Scholar 

  23. 23.

    Jemmett, A.E.: Factors affecting the growth of siloxane films on metal substrates. ASLE Trans. 16, 233–238 (1973)

    Article  CAS  Google Scholar 

  24. 24.

    Archard, J., Kirk, M.: Research notes: film thicknesses for a range of lubricants under severe stress. J. Mech. Eng. Sci. 1959–1982(6), 101–103 (1964)

    Article  Google Scholar 

  25. 25.

    Tabor, D., Winer, W.: Silicone fluids: their action as boundary lubricants. Tribol. Trans. 8, 69–77 (1965)

    CAS  Google Scholar 

  26. 26.

    Brown, E.: Methyl alkyl silicones- a new class of lubricants. ASLE Trans. 9, 31–35 (1966)

    Article  CAS  Google Scholar 

  27. 27.

    Rabinowicz, E.: Friction and Wear of Materials. Wiley, New York (1995)

    Google Scholar 

  28. 28.

    Blau, P. J.: Friction Science and Technology, vol. 100. CRC, Boca Raton, FL (2009)

  29. 29.

    Vinogradov, G., Nametkin, N., Nossov, M.: Anti-wear and anti-friction properties of polyorganosiloxanes and their mixtures with hydrocarbons. Wear 8, 93–111 (1965)

    Article  CAS  Google Scholar 

  30. 30.

    Zolper, T.J., Li, Z., Chen, C., Jungk, M., Marks, T.J., Chung, Y.-W., Wang, Q.: Lubrication properties of poly-alpha-olefin and polysiloxane lubricants: molecular structure-tribology relationships. Tribol. Lett. 48, 355–365 (2012)

    CAS  Google Scholar 

  31. 31.

    Zolper, T.J., Li, Z., Jungk, M., Stammer, A., Stoegbauer, H., Marks, T.J., Chung, Y.-W., Wang, Q.: Traction characteristics of siloxanes with aryl and cyclohexyl branches. Tribol. Lett 49, 301–311 (2013)

    Article  CAS  Google Scholar 

  32. 32.

    Zolper, T.J., Seyam, A.M., Chen, C., Jungk, M., Stammer, A., Stoegbauer, H., Marks, T.J., Chung, Y.-W., Wang, Q.: Energy efficient siloxane lubricants utilizing temporary shear-thinning. Tribol. Lett. 49, 525–538 (2013)

    Article  CAS  Google Scholar 

  33. 33.

    Schiefer, H.M.: Trifluoropropyl halophenyl substituted silicone copolymers—a new class of wide temperature range lubricants. ASLE Trans. 9, 36–46 (1966)

    Article  CAS  Google Scholar 

  34. 34.

    Spikes, H.A.: A literature review of lubricating properties of fluorosilicones and their comparison with other high temperature lubricants. Imp. Coll. Tribol. Sect. TS006/89, 1–35 (1989)

    Google Scholar 

  35. 35.

    Schiefer, H.Van., Dyke, J.: Boundary lubricating properties of fluoroalkyl silicones in bench and pump tests. ASLE Trans. 7, 32–42 (1964)

    Article  CAS  Google Scholar 

  36. 36.

    Dorinson, A. Ludema, K.C.: Mechanics and Chemistry in Lubrication, Vol. 9. Elsevier Science Ltd, Amsterdam (1985)

  37. 37.

    Sharma, S., Snyder, C., Gschwender, L.: Tribological behavior of some candidate advanced space lubricants. Tribol. Trans. 36, 321–325 (1993)

    Article  CAS  Google Scholar 

  38. 38.

    Corti, C., Savelli, P.: Perfluoropolyether lubricants. J. Synth. Lubr. 9, 311–330 (1993)

    Article  CAS  Google Scholar 

  39. 39.

    Sianesi, D., Caporiccio, G.: Polymerization and copolymerization studies on vinyl fluoride. J. Polym. Sci. Part A-1 Polym. Chem. 6, 335–352 (1968)

    Article  Google Scholar 

  40. 40.

    Sianesi, D., Zamboni, V., Fontanelli, R., Binaghi, M.: Perfluoropolyethers: their physical properties and behaviour at high and low temperatures. Wear 18, 85–100 (1971)

    Article  CAS  Google Scholar 

  41. 41.

    Marchionni, G., Ajroldi, G., Pezzin, G.: Molecular weight dependence of some rheological and thermal properties of perfluoropolyethers. Eur. Polym. J. 24, 1211–1216 (1988)

    Article  CAS  Google Scholar 

  42. 42.

    Caporiccio, G., Flabbi, L., Marchionni, G., Viola, G.: The properties and applications of perfluoropolyether lubricants. J. Synth. Lubr. 6, 133–149 (1989)

    Article  CAS  Google Scholar 

  43. 43.

    Scott, D., Blackwell, J.: NEL rolling contact tests—accelerated service simulation tests for lubricants and materials for rolling elements. Wear 17, 323–333 (1971)

    Article  Google Scholar 

  44. 44.

    Lutz, G.A., Jungk, M., Bryant, J.J., Lauer, R.S., Chobot, A., Mayer, T., Palmer, S., Kauffman, R.E.: Full life wind turbine gearbox lubricating fluids. Dow Corning Corporation, Midland, MI (2012)

    Book  Google Scholar 

  45. 45.

    Van Krevelen, D.W.: Properties of Polymers. Their Correlation with Chemical Structure, Their Numerical Estimation and Prediction from Additive Group Contribution, 3rd edn. Elsevier, Amsterdam (1990)

  46. 46.

    Bridgman, P.: Viscosities to 30,000 Kg/Cm. Proc. Am. Aca. Arts Sci. 77, 117–128 (1949)

    Google Scholar 

  47. 47.

    Lubrication, A. S. o. M. E. R. C. o.: Viscosity and density of over 40 lubricating fluids of known composition at pressures to 150,000 psi and temperatures to 425 F, Vol. 1. American Society of Mechanical Engineers, New York (1953)

  48. 48.

    Winer, W. O.: A Study of the Elastohydrodynamic Lubrication and High Pressure Rheological Behavior of a Series of Silicone Fluids. pp. 1–91. Georgia Tech. (1972)

  49. 49.

    Jakobsen, J., Sanborn, D., Winer, W.: Pressure viscosity characteristics of a series of siloxane fluids. ASME Trans. Ser. F J. Lubr. Technol. 96, 410–417 (1974)

    Article  CAS  Google Scholar 

  50. 50.

    Bair, S., Qureshi, F.: The generalized Newtonian fluid model and elastohydrodynamic film thickness. J. Tribol. 125, 70–75 (2003)

    Article  CAS  Google Scholar 

  51. 51.

    Bair, S., Qureshi, F.: The high pressure rheology of polymer-oil solutions. Tribol. Int. 36, 637–645 (2003)

    Article  CAS  Google Scholar 

  52. 52.

    Kuss, E.: Viskositats-Druckverhalten von flussigen Methyl-Phenylmethyl- und Cyclohexylmethyl-Siloxeanen. Erdol und Kohle-Erdgas-Petrochemie vereinigt mit Brennstoff-Chemie 27, 416–422 (1974)

    CAS  Google Scholar 

  53. 53.

    Gschwender, L., Snyder Jr, C.E., Sharma, S.K., Fultz, G.W.: High speed civil transport (HSCT) hydraulic fluid development. Tribol. Trans. 45, 185–192 (2002)

    Article  CAS  Google Scholar 

  54. 54.

    Smeeth, M., Spikes, H., Gunsel, S.: Boundary film formation by viscosity index improvers. Tribol. Trans. 39, 726–734 (1996)

    Article  CAS  Google Scholar 

  55. 55.

    Guangteng, G., Spikes, H.: Boundary film formation by lubricant base fluids. Tribol. Trans. 39, 448–454 (1996)

    Article  CAS  Google Scholar 

  56. 56.

    Krupka, I., Bair, S., Kumar, P., Khonsari, M., Hartl, M.: An experimental validation of the recently discovered scale effect in generalized Newtonian EHL. Tribol. Lett. 33, 127–135 (2009)

    Article  Google Scholar 

  57. 57.

    Katyal, P. Kumar, P.: Central film thickness formula for shear thinning lubricants in EHL point contacts under pure rolling. Tribol. Int. 48, 113–121 (2012)

    Google Scholar 

  58. 58.

    Peterson, M.B., Winer, W.O.: Wear control handbook. American Society of Mechanical Engineers, New York (1980)

    Google Scholar 

  59. 59.

    Hamrock, B. Dowson, D.: Isothermal elastohydrodynamic lubrication of point contacts. I—Theoretical formulation. ASME Trans. 98(2), 223–229 (1976)

    Google Scholar 

  60. 60.

    Hamrock, B. Dowson, D.: Isothermal elastohydrodynamic lubrication of point contacts. II—Ellipticity parameter results. ASME Trans. 98(3), 375–383 (1976)

    Google Scholar 

  61. 61.

    Hamrock, B. Dowson, D.: Isothermal elastohydrodynamic lubrication of point contacts. III—Fully flooded results. ASME Trans. 99(2), 264–276 (1977)

    Google Scholar 

  62. 62.

    Dowson, D. Toyoda, S.: A central film thickness formula for elastohydrodynamic line contacts In: Proceedings of 5 Leeds-Lyon Symposium on Tribology, pp 60–65 (1979)

  63. 63.

    Bair, S., Vergne, P., Marchetti, M.: The effect of shear-thinning on film thickness for space lubricants. Tribol. Trans. 45, 330–333 (2002)

    Article  CAS  Google Scholar 

  64. 64.

    Nijenbanning, G., Venner, C., Moes, H.: Film thickness in elastohydrodynamically lubricated elliptic contacts. Wear 176, 217–229 (1994)

    Article  Google Scholar 

  65. 65.

    Kweh, C., Evans, H., Snidle, R.: Micro-elastohydrodynamic lubrication of an elliptical contact with transverse and three-dimensional sinusoidal roughness. J. Tribol. 111, 577 (1989)

    Article  Google Scholar 

  66. 66.

    Kweh, C., Evans, H., Snidle, R.: Elastohydrodynamic lubrication of heavily loaded circular contacts. Proc Inst Mech Eng Part C J Mech Eng Sci 1989–1996(203), 133–148 (1989)

    Article  Google Scholar 

  67. 67.

    Venner, C., Bos, J.: Effects of lubricant compressibility on the film thickness in EHL line and circular contacts. Wear 173, 151–165 (1994)

    Article  Google Scholar 

  68. 68.

    Bhushan, B.: Introduction to tribology. Wiley, New York (2013)

    Book  Google Scholar 

  69. 69.

    Spikes, H., Olver, A.: Basics of mixed lubrication. Lubr. Sci. 16, 1–28 (2003)

    Article  Google Scholar 

  70. 70.

    Bondi, A.: van der Waals volumes and radii. J. Phys. Chem. 68, 441–451 (1964)

    Article  CAS  Google Scholar 

  71. 71.

    Bondi, A.: Physical properties of molecular crystals, liquids, and glasses. Wiley, New York (1968)

    Google Scholar 

  72. 72.

    Bahar, I., Zuniga, I., Dodge, R., Mattice, W.: Conformational statistics of poly (dimethylsiloxane). 1. Probability distribution of rotational isomers from molecular dynamics simulations. Macromolecules 24, 2986–2992 (1991)

    Article  CAS  Google Scholar 

Download references


The authors thank Dow Corning Corporation for support of this research.

Author information



Corresponding author

Correspondence to Thomas J. Zolper.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Zolper, T.J., Seyam, A., Li, Z. et al. Friction and Wear Protection Performance of Synthetic Siloxane Lubricants. Tribol Lett 51, 365–376 (2013).

Download citation


  • Silicones
  • Synthetic base stocks
  • Boundary lubrication friction
  • Abrasive wear