화학공학소재연구정보센터
Journal of Industrial and Engineering Chemistry, Vol.15, No.5, 687-693, September, 2009
Influence of soap/polymer concentration ratio on the rheological properties of lithium lubricating greases modified with virgin LDPE
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The main goal of this work was to study the feasibility of using a low-density polyethylene (LDPE) as additive to improve the rheological properties of lithium lubricating greases. The combined effect that both soap and LDPE concentrations exerts on the rheology of lithium lubricating greases and its relationship with grease microstructure were studied according to an experimental design based on the response surface methodology (RSM). Different lubricating grease formulations were manufactured by modifying lithium 12-hydroxystereate and LDPE concentrations. Small-amplitude oscillatory shear (SAOS) and viscous flow measurements, as well as mechanical stability tests, were performed. In addition to these, environmental scanning electronic microscopy (ESEM) was used to determine grease microstructure. LDPE was found to be a useful additive to modify grease rheology, acting as filler in the entangled soap network. The values of both apparent viscosity and linear viscoelasticity functions increase with soap and LDPE concentration. However, the addition of LDPE distorts soapmicrostructural network, yielding greases with lower relative elastic characteristics.
  1. Boyde S, Green Chem., 4, 293 (2002)
  2. Hamnelid L, in: Balan C (Ed.), The Rheology of Lubricating Greases, ELGI, Amsterdan (1999)
  3. Delgado MA, Sanchez MC, Valencia C, Franco JM, Gallegos C, Chem. Eng. Res. Des., 83(A9), 1085 (2005)
  4. Delgado MA, Valencia C, Sanchez MC, Franco JM, Gallegos C, Ind. Eng. Chem. Res., 45(6), 1902 (2006)
  5. Czarny R, Paszkowski M, J. Synt. Lubr., 24, 19 (2007)
  6. Lee KW, Mei BX, Bo Q, Kim YW, Chung KW, Han Y, J. Ind. Eng. Chem., 13(4), 530 (2007)
  7. Al-Sammerrai DJ, J. Appl. Polym. Sci., 31, 1 (1986)
  8. Chai XS, Yoon SH, J. Ind. Eng. Chem., 13(2), 244 (2007)
  9. Ver Strate G, Struglinski MJ, Am. Chem. Soc. Symp. Ser., 462, 256 (1991)
  10. Samgina VV, Fuks IG, Bakaleinikov MB, Chem. Technol. Fuels Oils, 9, 490 (1973)
  11. Vdovichenko PN, Voznyuk FZ, Ishehuk LP, Artemev YI, Technol. Fuels Oils, 6, 35 (1977)
  12. NLGI, Lubricating Greases Guide, National Lubricating Grease Institute, Kansas City, MO (1994)
  13. Choi HJ, Lim ST, Izumisawa S, Jhon MS, Tribol. Int., 38, 682 (2005)
  14. Delgado MA, Franco JM, Kuhn E, Ind. Lubr. Tribol., 60, 37 (2008)
  15. Guo Q, Chung PS, Jhon MS, Choi HJ, Macromol. Theory Simul., 17, 454 (2008)
  16. Moreno G, Valencia C, de Paz MV, Franco JM, Gallegos C, Ind. Eng. Chem. Res., 45(11), 4001 (2006)
  17. Moreno G, Valencia C, de Paz MV, Franco JM, Gallegos C, Chem. Eng. Process., 47(4), 528 (2008)
  18. Martın-Alfonso JE, Valencia C, Sanchez MC, Franco JM, Gallegos C, Polym. Eng. Sci., 48, 1112 (2008)
  19. Andersson LHU, Hjertberg T, Polymer, 47(1), 200 (2006)
  20. Franco JM, Delgado MA, Valencia C, Sanchez MC, Gallegos C, Chem. Eng. Sci., 60(8-9), 2409 (2005)
  21. Garcia-Morales JA, Franco JM, Valencia C, Sanchez MC, Gallegos C, J. Ind. Eng. Chem., 10(3), 368 (2004)
  22. Montgomery DC, Design and Analysis of Experiments, John Wiley & Sons, New York (1996)
  23. Balan C, Franco JM, Tribol. Trans., 44, 53 (2001)
  24. Delgado MA, Franco JM, Partal P, Gallegos C, Chem. Eng. Process., 44(7), 805 (2005)
  25. Garcia-Morales M, Partal P, Navarro FJ, Martinez-Boza F, Gallegos C, Energy Fuels, 18(2), 357 (2004)
  26. Vinogradov GV, Sinitsyn VV, J. Inst. Petrol., 47, 357 (1961)
  27. Magnin JM, Piau JM, J. Mater. Res., 4, 990 (1988)
  28. Couronne I, Vergne P, Mazuyer D, Truong-Dinh N, Girodin D, Tribol. Trans., 46, 31 (2003)
  29. Delgado MA, Valencia C, Sanchez MC, Franco JM, Gallegos C, Tribol. Lett., 23, 47 (2006)
  30. Madiedo JM, Franco JM, Valencia C, Gallegos C, J. Tribol., 122, 590 (2000)
  31. Ferry JD, Viscoelastic Properties of Polymers, 3rd edition, John Wiley & Sons, New York (1980)
  32. Hyun YH, Lim ST, Choi HJ, Jhon MS, Macromolecules, 34(23), 8084 (2001)
  33. Baumgaertel M, De Rosa ME, Machado J, Masse M, Winter HH, Rheol. Acta, 31, 78 (1992)
  34. Liu CY, He JS, van Ruymbeke E, Keunings R, Bailly C, Polymer, 47(13), 4461 (2006)
  35. Lundberg J, Hoglund E, Tribol. Int., 33, 217 (2000)