Synthesis and tribological characteristics of oligoorganosiloxanes with higher n-alkyl substituents

A procedure was developed for hydrosilylation of alpha -olefins with oligoh ydrosiloxanes, and a series of comb-shaped orgnosiloxanes of the general fo rmula R3S'O(R2SiO)(m)(RR'S'O)(n)SiR3 (where R is CH3, C2H5; R' is n-alkyl C -8-C-18) with random distribution of dimethylsiloxane (or diethylsiloxane) and methylalkylsiloxane (or ethylalkylsiloxane) units were obtained. The ph ysicochemical characteristics of these oligomers were studied, with particu lar attention given to their lubricating properties (diameter of the wear s pot and critical jamming load), which were compared to those of lubricating oils based on organosilicon compounds (PMS-100, KhS-2-1) and hydrocarbon-b ased MS-20 oil.