In this study,lithium complex grease(LCG)and polyurea grease(PUG)were synthesized using mineral oil(500 SN)and polyalphaolefin(PAO40)as base oil,adsorbed onto lithium complex soap and polyurea as thickeners,respective...In this study,lithium complex grease(LCG)and polyurea grease(PUG)were synthesized using mineral oil(500 SN)and polyalphaolefin(PAO40)as base oil,adsorbed onto lithium complex soap and polyurea as thickeners,respectively.The effects of grease formulation(thickener and base oil with different amounts(80,85,and 90 wt%)on the corrosion resistance and lubrication function were investigated in detail.The results have verified that the as-prepared greases have good anti-corrosion ability,ascribed to good salt-spray resistance and sealing function.Furthermore,the increase in the amount of base oil reduces the friction of the contact interface to some extent,whereas the wear resistance of these greases is not consistent with the friction reduction,because the thickener has a significant influence on the tribological property of greases,especially load-carrying capacity.PUG displays better physicochemical performance and lubrication function than LCG under the same conditions,mainly depending on the component/structure of polyurea thickener.The polyurea grease with 90 wt%PAO displays the best wear resistance owing to the synergistic lubrication of grease-film and tribochemical film,composed of Fe_(2)O_(3),FeO(OH),and nitrogen oxide.展开更多
The depletion of petroleum resources and the intensification of environmental problems have necessitated the development of renewable products from bio-based chemicals instead of petroleum resources.Herein,a new kind ...The depletion of petroleum resources and the intensification of environmental problems have necessitated the development of renewable products from bio-based chemicals instead of petroleum resources.Herein,a new kind of ester lubricating oil,isooctyl furan dicarboxylate(isooctyl-FD),was prepared from bio-based 2,5-furandicarboxylic acid.The structure of isooctyl-FD was evaluated using nuclear magnetic resonance imaging and high-resolution mass spectroscopy.Its physicochemical and tribological properties including thermal and oxidation stabilities,flash point and pour point,viscosity and viscosity index,and friction-reducing and anti-wear properties were systematically evaluated.The results show that isooctyl-FD has comparable thermal and oxidation stability to the synthetic ester lubricating oil,isooctyl sebacate(isooctyl-S).Its friction-reducing and anti-wear properties are superior to isooctyl-S;however,its viscosity-temperature and low-temperature properties are inferior to isooctyl-S.展开更多
基金the financial support provided by the National Natural Science Foundation of China(No.51705435)Fundamental Research Funds for the Central Universities(2018GF05)Key Laboratory of Material Corrosion and Protection of Sichuan(2018CL14)。
文摘In this study,lithium complex grease(LCG)and polyurea grease(PUG)were synthesized using mineral oil(500 SN)and polyalphaolefin(PAO40)as base oil,adsorbed onto lithium complex soap and polyurea as thickeners,respectively.The effects of grease formulation(thickener and base oil with different amounts(80,85,and 90 wt%)on the corrosion resistance and lubrication function were investigated in detail.The results have verified that the as-prepared greases have good anti-corrosion ability,ascribed to good salt-spray resistance and sealing function.Furthermore,the increase in the amount of base oil reduces the friction of the contact interface to some extent,whereas the wear resistance of these greases is not consistent with the friction reduction,because the thickener has a significant influence on the tribological property of greases,especially load-carrying capacity.PUG displays better physicochemical performance and lubrication function than LCG under the same conditions,mainly depending on the component/structure of polyurea thickener.The polyurea grease with 90 wt%PAO displays the best wear resistance owing to the synergistic lubrication of grease-film and tribochemical film,composed of Fe_(2)O_(3),FeO(OH),and nitrogen oxide.
基金National Natural Science Fund(51675006)the project of Science and Technology Department of Shaanxi Province(2016JZ017)the Local Servicing Research Project of the Education Department of Shanxi Province(15JF007).
文摘The depletion of petroleum resources and the intensification of environmental problems have necessitated the development of renewable products from bio-based chemicals instead of petroleum resources.Herein,a new kind of ester lubricating oil,isooctyl furan dicarboxylate(isooctyl-FD),was prepared from bio-based 2,5-furandicarboxylic acid.The structure of isooctyl-FD was evaluated using nuclear magnetic resonance imaging and high-resolution mass spectroscopy.Its physicochemical and tribological properties including thermal and oxidation stabilities,flash point and pour point,viscosity and viscosity index,and friction-reducing and anti-wear properties were systematically evaluated.The results show that isooctyl-FD has comparable thermal and oxidation stability to the synthetic ester lubricating oil,isooctyl sebacate(isooctyl-S).Its friction-reducing and anti-wear properties are superior to isooctyl-S;however,its viscosity-temperature and low-temperature properties are inferior to isooctyl-S.