Synthesis and Tribological Characteristics of Oligoorganosiloxanes with Higher n-Alkyl Substituents

A procedure was developed for hydrosilylation of α-olefins with oligohydrosiloxanes, and a series of comb-shaped organosiloxanes of the general formula R3SiO(R2SiO)m(RR'SiO)nSiR3 (where R is CH3, C2H5; R' is n-alkyl C8-C18) with random distribution of dimethylsiloxane (or diethylsiloxane) and methylalkylsiloxane (or ethylalkylsiloxane) units were obtained. The physicochemical characteristics of these oligomers were studied, with particular attention given to their lubricating properties (diameter of the wear spot and critical jamming load), which were compared to those of lubricating oils based on organosilicon compounds (PMS-100, KhS-2-1) and hydrocarbon-based MS-20 oil.