Synergistic lubrication effect of antioxidant and low content ZDDP on PFPE grease
Industrial Lubrication and Tribology
ISSN: 0036-8792
Article publication date: 26 July 2021
Issue publication date: 3 August 2021
Abstract
Purpose
The purpose of this study is to reduce the use of Zinc dialkyl dithiophosphates (ZDDP) and improve the frictional properties and thermal oxidation stability of Perfluoropolyether (PFPE) grease by adding antioxidant additives. The addition of antioxidants can reduce the consumption of ZDDP as an antioxidant, thus improving the anti-wear efficiency of ZDDP and reducing the excess phosphorus element in the grease.
Design/methodology/approach
In this study, an antioxidant with good comprehensive performance was selected from several antioxidants by tribological tests and high-temperature tests. Then, the effect of its combination additive with ZDDP on PFPE grease was investigated. The anti-wear property, anti-friction property, thermal oxidation stability and extreme pressure property of greases containing different proportions of ZDDP and antioxidant were tested by four-ball tester and synchronous thermal analyzer (STA). The effects of additives on properties of grease were analyzed by SEM, EDS, LSCM, XPS and FT-IR.
Findings
The research shows that 2,6-Di-tert-butyl-4-methylphenol (BHT) can be used as an antioxidant in combined additives to reduce the antioxidant reactions of ZDDP, thus improving the anti-wear efficiency of ZDDP and further enhancing the anti-wear performance of the grease. Moreover, BHT and ZDDP have a synergistic effect on the high temperature performance of the PFPE grease due to their different antioxidant mechanisms.
Social implications
In this paper, the problems related to PFPE grease are studied, which has a certain guiding effect on the industrial application of fluorine grease and the related formulation design.
Originality/value
In this paper, the properties of PFPE grease under different lubricating condition were studied. The synergistic lubrication effect of antioxidant and ZDDP are discussed. It provides experimental and theoretical support for reducing the content of ZDDP and improving the performance of additives.
Keywords
Acknowledgements
The authors acknowledge financial support from the National Natural Science Foundation of China (No. 51705489) and the Innovation Development Fund of the Chinese Academy of Physics (No. PY2019071).
Citation
Qi, P., Wang, S., Li, J., Li, Y. and Dong, G. (2021), "Synergistic lubrication effect of antioxidant and low content ZDDP on PFPE grease", Industrial Lubrication and Tribology, Vol. 73 No. 5, pp. 830-838. https://doi.org/10.1108/ILT-01-2021-0017
Publisher
:Emerald Publishing Limited
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