LOW-TEMPERATURE ECO-FRIENDLY GREASE AND A METHOD FOR PRODUCTION THEREOF Russian patent published in 2020 - IPC C10M119/20 C10M119/24 C10M171/06 C10M177/00 C10N30/02 C10N20/06 

FIELD: chemistry.

SUBSTANCE: invention relates to production of greases which are recommended for lubrication of heavily loaded mechanisms, namely: main friction assemblies of vehicles, tractors, all-terrain vehicles operating in a wide range of speeds and corresponding mechanical loads, as well as in a wide range of temperatures, including low ambient temperatures (from minus 60 to plus 200 °C). Low-temperature eco-friendly grease contains base ester oil, oligourea based thickener obtained by reacting aromatic polyisocyanate, fatty amine or its mixture with ethylenediamine, and additionally a second thickener – nanofibrillar cellulose NFC with a mean diameter of fibrils from 10 to 700 nm and a length of up to 1 mcm, dispersed in ester oil with degree of water cut of not more than 7 wt%, at following ratio of components, wt%: polyurea thickener – 8–25, nanofibrillar cellulose – 1–5, basic ester oil – balance. Additionally, the lubricant contains cetearyl alcohol in amount of 1–5 wt%. Method of producing low-temperature environmentally friendly grease involves dissolving amine or a mixture thereof in basic ester oil, adding polyisocyanate to the obtained solution, stirring and heating to 80–100 °C to form a polyurea thickener. Solution in base ester oil of fatty amine or its mixture with ethylenediamine before introduction of polyisocyanate solution is mixed with dispersion of nanofibrillar cellulose in the same basic ester oil obtained by successive replacement of dispersion medium with reduction of its polarity and subsequent ultrasonic treatment for 2–3 minutes. Then a solution of polyisocyanate is added to the dispersion in basic ester oil and components are mixed at a rate of not less than 100 s^-1 for at least 10 minutes, after which the mixture is held for a day at room temperature in a thin layer. When adding polyisocyanate solution, cetearyl alcohol is additionally added.

EFFECT: high frost resistance and improved anti-wear and tribological characteristics of low-temperature environmentally friendly grease.

4 cl, 3 dwg, 2 tbl, 9 ex