Tribotechnical Characteristics of Lubricants from the Series of Perfluorinated Polytriazines

Despite high thermal-oxidative stability and chemical inertness, standard perfluoropolyether lubricants are susceptible to catalytic decomposition at high temperatures in the presence of metals, leading to corrosion and limiting their use. A solution to this problem may be the use of perfluoroalkyl-substituted triazines, which exhibit significantly higher corrosion-oxidative stability. The aim of this study was to evaluate the feasibility of using synthesized perfluoroalkyl-substituted polytriazines (PFPT) with molecular weights ranging from 932 to 2920 as lubricants and compare their tribological properties with those of the commercial perfluoro-polyether (PFPE).

A number of PFPT samples (bis-triazines and oligotriazine) were studied by DSC, TGA methods and boiling points were determined. Tribological tests were carried out using the plane-to-plane design (ShKh15 steel/12Kh1 steel) at room temperature. The average friction coefficient (f_av) was determined for each PFPT sample, with f_av consistently increasing with increasing PFPT molecular weight. It was shown that the friction coefficient of PFPT (0,12—0,18) is comparable to that of PFPE (0,13) and significantly lower than that of dry friction (0,27).

The results confirm the potential of PFPT as chemically inert and thermally stable lubricants. Their tribotechnical characteristics are comparable to those of commercial PFPE, indicating the possibility of combined use or replacement.

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