Lubricating compositions for motor vehicles
View Patent ↗Disclosed are lubricating compositions and base oils for motor vehicles, specifically for engines, gearboxes, or vehicle axle assemblies. The lubricating composition contains an oil-soluble polymer that is a specific polyalkyl glycol or a specific polyalkylene glycol (PAG). Also described is use of the lubricating composition for reducing fuel consumption in a vehicle provided with an engine, an axle assembly, or a gearbox that are lubricated using the lubricating composition or the specific PAG.
1. A lubricating composition comprising at least one oil of formula (I)
wherein
R represents a linear or branched C 1 -C 30 alkyl group;
m and n represent independently an average number ranging from 1 to 5.
2. The lubricating composition according to claim 1 wherein R represents a group selected from the group consisting of a linear C 8 alkyl group; a branched C 8 alkyl group; a linear C 9 alkyl group; a branched C 9 alkyl group; a linear C 10 alkyl group; a branched C 10 alkyl group; a linear C 11 alkyl group; a branched C 11 alkyl group; a linear C 12 alkyl group; a branched C 12 alkyl group; a linear C 13 alkyl group; a branched C 13 alkyl group; a linear C 14 alkyl group; a branched C 14 alkyl group; a linear C 15 alkyl group; and a branched C 15 alkyl group.
3. The lubricating composition according to claim 1 wherein:
m is greater than or equal to n; or
m represents an average number ranging from 2 to 4.5; or
n represents an average number ranging from 1.5 to 4.
4. The lubricating composition according to claim 1 wherein:
m represents an average number ranging from 2.5 to 3.5; or
n represents an average number ranging from 2 to 3.
5. The lubricating composition according to claim 1 wherein:
m represents an average number equal to 2.5 and n represents an average number equal to 2; or
m represents an average number equal to 3.5 and n represents an average number equal to 2.8.
6. The lubricating composition according to claim 1 comprising at least one oil of formula (I) wherein:
(a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 2.5 to 4.5 mm 2 ·s −1 ; or for which
(b) the viscosity index is greater than 160 or is comprised between 160 and 210; or for which
(c) the pour point is less than −40° C.; or for which
(d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 1,200 mPa·s.
7. The lubricating composition according to claim 1 , comprising at least one oil of formula (I) wherein:
(a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 2.5 to 4.5 mm 2 ·s −1 ;
(b) the viscosity index is greater than 160 or is comprised between 160 and 210;
(c) the pour point is less than −40° C.; and
(d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 1,200 mPa·s.
8. The lubricating composition according to claim 1 , comprising at least one oil of formula (I) wherein m represents an average number equal to 2.5 and n represents an average number equal to 2 and wherein:
(a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 2.5 to 3.5 mm 2 ·s −1 ;
(b) the viscosity index is comprised between 160 and 180;
(c) the pour point is less than −40° C.; and
(d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 500 mPa·s.
9. The lubricating composition according to claim 1 , comprising at least one oil of formula (I) wherein m represents an average number equal to 3.5 and n represents an average number equal to 2.8 and wherein:
(a) the kinematic viscosity at 100° C., measured according to the ASTM D445 standard, ranges from 3.5 to 4.5 mm 2 ·s −1 ;
(b) the viscosity index is comprised between 180 and 210;
(c) the pour point is less than −50° C.; and
(d) the dynamic viscosity (CCS) at −35° C., measured according to the ASTM D5293 standard is less than 1,200 mPa·s.
10. The lubricating composition according to claim 1 , comprising from 2 to 60% by weight of at least one oil of formula (I).
11. The lubricating composition according to claim 8 , comprising from 5 to 40% by weight of at least one oil of formula (I).
12. The lubricating composition according to claim 9 , comprising from 5 to 35% by weight of at least one oil of formula (I).
13. The lubricating composition according to claim 1 , further comprising:
at least one other base oil selected from the group consisting of oils of group III, oils of group IV and oils of group V; or
at least one additive; or
at least one other base oil selected from the group consisting of oils of the group III, oils of group IV and oils of group V and at least one additive.
14. A method for reducing the traction coefficient of a transmission oil, comprising providing and applying at least one lubricating composition according to claim 1 .
15. A method for reducing the fuel consumption of an engine, or for reducing the fuel consumption of a vehicle equipped with a transmission, comprising providing and applying a suitable amount of at least one lubricating composition according to claim 1 .