ISSN 1068-3666, Journal of Friction and Wear, 2010, Vol. 31, No. 5, pp. 387–397. © Allerton Press, Inc., 2010. Original Russian Text © A.G. Ponomarenko, G.G. Chigarenko, A.S. Burlov, A.V. Bicherov, T.A. Shiryaeva, B.G. Konoplev, O.A. Ageev, A.S. Kolomiitsev, S.B. Zaichenko, V.A. Chetverikova, A.D. Garnovskii, V.I. Minkin, 2010, published in Trenie i Iznos, 2010, Vol. 31, No. 5, pp. 511–521. 387 INTRODUCTION Polyorganosiloxane liquids have unique rheologi- cal characteristics and high thermal stability, allowing their application for the preparation of oils and lubri- cants for various functions. However, the tribotechni- cal characteristics of these lubricants are low, and it is difficult to increase them by the introduction of stan- dard additives due to the specificity of the properties of the oils themselves and the tribochemical processes with the participation of organosilicon compounds [1–3]. One of the current methods of enhancing the lubri- cating properties of oils is the realization of the effect of “wearless friction,” or selective transfer (ST), which appears for coal oils and aqueous-alcoholic mixtures upon the introduction of salts and complexes of 3d-metals into their composition [4–9]. Specifically, salicylideneimines of 3d-metals direct tribochemical processes towards the formation of thin films of com- plex structure on the friction surfaces. These films contain a layer of transition metal and polymer in the form of a gel swollen in the lubricant medium; this allows them to be potentially used as additives to oils [10, 11]. Other tribologically active compositions involving metallized nanosized particles are known [12–19]. Of special interest is the realization of ST in the medium of silicon oils, which in the pure form cause the heightened wear of the steel–steel friction pair [2, 3]. PROBLEM STATEMENT In the current work, we studied the possibility of the realization of ST in compositions based on polyor- ganosiloxane liquids by the introduction of azome- thine complexes of transition metals, namely, copper, nickel, cobalt, and zinc. The theoretical and practical interest is the study of the composition and structure of the films at friction surfaces determining the antifriction, antiwear, and load characteristics of the lubricant composition. TEST METHODS Tribotests were carried out on a face friction machine of the AE-5 type. The moving samples and the rider were made of steel 45. The load was increased stepwise; the slip velocity was 0.8 m/s. The maximum allowable load and the coefficient of friction were Study of Lubricating Compositions Based on Polyorganosiloxanes Involving Azomethine Metalocomplexes A. G. Ponomarenko a, *, G. G. Chigarenko a , A. S. Burlov b , A. V. Bicherov c , T. A. Shiryaeva a , B. G. Konoplev d , O. A. Ageev d , A. S. Kolomiitsev d , S. B. Zaichenko b , V. A. Chetverikova e , A. D. Garnovskii b , and V. I. Minkin b, c, e a NPK OOO Don-Invek, pr. Stachki 194/2, Rostov-na-Donu, 344090 Russia *e-mail: invec@mail.ru b Research Institute of Physical and Organic Chemistry, Southern Federal University, pr. Stachki 194/2, Rostov-on-Don, 344090 Russia c Southern Scientific Center, Russian Academy of Sciences, pr. Chekhova 41, Rostov-on-Don, 344006 Russia d Technology Institute, Southern Federal University, per. Nekrasovskii 44, Taganrog, 347928 Russia e Chemical Department, Southern Federal University, ul. Zorge 7, Rostov-on-Don, 344090 Russia Received October 21, 2009 Abstract—Azomethine complexes of copper, nickel, cobalt, and zinc are demonstrated to favor selective transfer in the medium of polyorganosiloxanes. In studies of the friction surfaces with the use of methods of optical and scanning electron microscopy, energy-dispersion electron probe X-ray microanalysis, and infra- red frustrated total internal reflection spectroscopy, the formation of a transition-metal and tribopolymer film containing polyorganosiloxane fragments is found. Keywords: polyorganosiloxanes, additives, coordination compounds, azomethines, esters, tribochemical reactions, friction polymers. DOI: 10.3103/S1068366610050119