Additives Based on Poly(tetrafluoroethylene) for Improving Wear Resistance

Abstract:

During the irradiation of high molecular weight poly (tetrafluoroethylene) (PTFE) in presence of oxygen perfluoroalkyl (peroxy) radicals and functional groups are formed which allow chemical coupling reactions (cc = chemical compatibilized) with oils and plastics. The micropowder resulting from the irradiation of PTFE are used in base oils to improve the tribological properties significantly if oil molecules are covalently linked to primary PTFE particles in the oil dispersion. These oil-PTFE-cc-dispersions show primarily anti-wear (AW) properties. The use of additional reactive groups (e.g. phosphite groups) in the oil gives the dispersions extreme pressure (EP) properties additionally. This article demonstrates the usefulness of the oil-PTFE-cc-dispersions in rolling bearings and in ropes using phosphite-modified PTFE products as additive in lubricants. The investigations are completed by wear tests with different contact geometries. A model is shown to explain the effect of phosphite groups on 100Cr6 metallic surfaces.Keyword s: PTFE, high performance lubricant, oil-PTFE-cc dispersion

• Periodical: Key Engineering Materials (Volume 674)
• Pages: 195-200
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.674.195
• Online since: January 2016
• Authors: Thorsten Hoffmann*, Dieter Lehmann, Martin Anders, Thorsten Schmidt, Thorsten Heinze, Markus Michael
• Keywords: High Performance Lubricant, Oil-PTFE-cc Dispersion, PTFE

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