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The paper describes methods for manufacturing few-layered graphene by liquid-phase shear exfoliation of graphite and modifying a lubricant using this graphene. The principal difference of the presented technology lies in the fact that graphite is exfoliated in a base oil used to produce the lubricant. Besides, a device was developed to implement the graphite exfoliation process, in which shear forces mainly act on graphite particles. The shear exfoliation was experimentally studied, and it was established that the friction coefficient and the wear spot diameter decrease by 35 and 25 %, respectively, due to the lubricant modification with 0.12-wt.% few-layered graphene. [ABSTRACT FROM AUTHOR]

The paper analyzes the known methods for synthesizing low-defect graphene nanoplatelets (GNPs) of different structure. The optimal GNP synthesis procedure was determined - namely, intercalation of natural graphite using peroxosulfate compounds, exfoliation of the obtained compounds, removal of the intercalant, and exfoliation using ultrasonic treatment under various conditions. This technique allows production of GNPs with a thickness of less than 10 graphene layers. Furthermore, a method for surface modification of the synthesized GNPs using titanium stearate was developed to ensure their hydrophobicity and good compatibility with non-polar media. [ABSTRACT FROM AUTHOR]

The present paper considers the effect of nanomaterials on the electrical conductivity of an elastic composition based on polychloroprene rubber. Taunit-M multi-walled carbon nanotubes and nitrogen-doped graphene were employed as electrically conductive components. The conductive polymeric material synthesized can be used in a wide operating range, and moreover, it possesses high electrical conductivity. [ABSTRACT FROM AUTHOR]

The paper describes the results of a study of the graphene concentration effect on the viscosity of a base oil for preparing plastic lubricants. It was established that the viscosity of the graphene masterbatch reaches the viscosity of the plastic lubricant at 9-11 wt% for few-layered graphene and 5-8 wt% for multi-layered one. Moreover, at graphene concentrations of 0.1 wt% or more, the wear spot diameter decreases by at least 50 %, whereas the load wear index and bearing strength increase almost 3-fold and 4-fold, respectively. [ABSTRACT FROM AUTHOR]