NEW ADDITIVES IMPROVING VISCOSITY INDEX Russian patent published in 2024 - IPC C08F220/20 C08L33/08 C10M145/14 C10N30/02 

FIELD: chemistry.

SUBSTANCE: invention relates to polyalkyl (meth)acrylate-based copolymers containing: (a) from 20 to 35 wt.% linear or branched C₁-C₄-alkyl (meth)acrylates; (b) from 50 to 65 wt.% having linear or branched chain C₁₀-C₁₆-alkyl(meth)acrylates; and (c) from 7 to 15 wt.% linear chain C₁₈-C₂₄-alkyl(meth)acrylates, characterized by an average carbon number of from 7.0 to 7.5 and a weight average molecular weight Mw ranging from 300,000 g/mol to 1,000,000 g/mol, where the average carbon number corresponds to the average molar number of all carbon atoms contained in the alkyl residues of the alkyl(meth)acrylate units forming the polyalkyl(meth)acrylate-based copolymer, and the weight average molecular weight Mw is determined by gel permeation chromatography (GPC) using polymethyl methacrylate calibration, wherein the polyalkyl(meth)acrylate-based copolymers are selected from the group consisting of: polymer A consisting of 25.0 wt.% methyl methacrylate (MMA), 5.0 wt.% n-butyl methacrylate (BMA), 0.1 wt.% isodecyl methacrylate (IDMA), 18.0 wt.% C₁₂ -C₁₅-alkyl methacrylate (DPMA), 31.9 wt.% lauryl methacrylate (LMA) and 20.0 wt. % stearyl methacrylate (SMA), with Mw equal to 541,000 g/mol and average carbon number equal to 7.2; or polymer B, consisting of 25.0 wt.% methyl methacrylate (MMA), 55.0 wt.% lauryl methacrylate (LMA) and 20.0 wt.% stearyl methacrylate (SMA), with Mw equal to 437,000 g/mol and average carbon number equal to 7.5; or polymer C, consisting of 25.0 wt.% methyl methacrylate (MMA), 2.5 wt.% n-butyl methacrylate (BMA), 18.0 wt.% C₁₂-C₁₅-alkyl methacrylate (DPMA), 34.5 wt.% lauryl methacrylate (LMA) and 20.0 wt.% stearyl methacrylate (SMA), with Mw equal to 521,000 g/mol and average carbon number equal to 7.4; or polymer D, consisting of 25.0 wt.% methyl methacrylate (MMA), 5.0 wt.% n-butyl methacrylate (BMA), 0.1 wt.% isodecyl methacrylate (IDMA), 18.0 wt.% C₁₂-C₁₅-alkyl methacrylate (DPMA), 29.4 wt.% lauryl methacrylate (LMA) and 22.5 wt.% stearyl methacrylate (SMA), with Mw equal to 539,000 g/mol and average carbon number equal to 7.3; or polymer E, consisting of 25.0 wt.% methyl methacrylate (MMA), 7.0 wt.% n-butyl methacrylate (BMA), 0.1 wt.% isodecyl methacrylate (IDMA), 18.0 wt.% C₁₂-C₁₅-alkyl methacrylate (DPMA), 27.4 wt.% lauryl methacrylate (LMA) and 22.5 wt.% stearyl methacrylate (SMA), with Mw equal to 497,000 g/mol and average carbon number equal to 7.1; or polymer F, consisting of 25.0 wt.% methyl methacrylate (MMA), 5.0 wt.% n-butyl methacrylate (BMA), 0.1 wt.% isodecyl methacrylate (IDMA), 18.0 wt.% C₁₂-C₁₅-alkyl methacrylate (DPMA), 31.9 wt.% lauryl methacrylate (LMA) and 20.0 wt.% stearyl methacrylate (SMA), with Mw equal to 951000 g/mol and average carbon number equal to 7.2; or polymer G, consisting of 25.0 wt.% methyl methacrylate (MMA), 5.0 wt.% n-butyl methacrylate (BMA), 0.1 wt.% isodecyl methacrylate (IDMA), 18.0 wt.% C₁₂-C₁₅-alkyl methacrylate (DPMA), 31.9 wt.% lauryl methacrylate (LMA) and 20.0 wt.% stearyl methacrylate (SMA), with Mw equal to 635,000 g/mol and average carbon number equal to 7.2; or polymer H, consisting of 25.0 wt.% methyl methacrylate (MMA), 5.0 wt.% n-butyl methacrylate (BMA), 0.1 wt.% isodecyl methacrylate (IDMA), 18.0 wt.% C₁₂-C₁₅-alkyl methacrylate (DPMA), 31.9 wt.% lauryl methacrylate (LMA) and 20.0 wt.% stearyl methacrylate (SMA), with Mw equal to 451,000 g/mol and average carbon number equal to 7.2; or polymer I, consisting of 25.0 wt.% methyl methacrylate (MMA), 5.0 wt.% n-butyl methacrylate (BMA), 0.1 wt.% isodecyl methacrylate (IDMA), 18.0 wt.% C₁₂-C₁₅-alkyl methacrylate (DPMA), 31.9 wt.% lauryl methacrylate (LMA) and 20.0 wt.% stearyl methacrylate (SMA), with Mw equal to 343,000 g/mol and average carbon number equal to 7.2. Compositions of additives for use in motor oil compositions containing the above polymers are also described, and a method of maintaining kinematic viscosity at 100°C at a level of at least 6.9 mm²/s at a given viscosity value at high temperature and high shear rate at 150°C equal to 2.6 mPa∙s, and a simultaneous decrease in viscosity at high temperature and high shear rate at 100°C of a composition of lubricating oils containing the above additives.

EFFECT: improvement in the viscosity index and characteristics of the high-fuel assemblies of the lubricating oil composition.

9 cl, 7 tbl, 19 ex