Compositions are obtained by mixing at least one oligomer A1, which is obtained by copolymerizing at least two monomers functionalized by diol functions with at least one second monomer, with at least one compound A2 having at least two boron ester functions. The compositions exhibit very varied rheological properties depending on the proportion of the compounds A1 and A2 used. A composition is also obtained by mixing at least one lubricating oil with such a composition of associative and exchangeable polymers, and the use of this composition to lubricate a mechanical part.

Compositions are obtained by mixing at least one oligomer A1, which is obtained by copolymerizing at least two monomers functionalized by diol functions with at least one second monomer, with at least one compound A2 having at least two boron ester functions. The compositions exhibit very varied rheological properties depending on the proportion of the compounds A1 and A2 used. A composition is also obtained by mixing at least one lubricating oil with such a composition of associative and exchangeable polymers, and the use of this composition to lubricate a mechanical part.

In the field of lubricating compositions, in particular to the Fuel Economy (FE) properties of lubricating compositions, there is disclosed the combined use of at least one derivative of molybdenum and at least one derivative of boron to maintain the Fuel Economy (FE) properties of a lubricating composition also including at least one base oil. Also disclosed is a use, within a lubricating composition including at least one base oil, of a combination of at least one derivative of molybdenum and at least one derivative of boron, and at least 30 ppm and at most 600 ppm of born boron relative to the weight of the lubricating composition to preserve the Fuel Economy (FE) properties of this lubricating composition.

In the field of lubricating compositions, in particular to the Fuel Economy (FE) properties of lubricating compositions, there is disclosed the combined use of at least one derivative of molybdenum and at least one derivative of boron to maintain the Fuel Economy (FE) properties of a lubricating composition also including at least one base oil. Also disclosed is a use, within a lubricating composition including at least one base oil, of a combination of at least one derivative of molybdenum and at least one derivative of boron, and at least 30 ppm and at most 600 ppm of born boron relative to the weight of the lubricating composition to preserve the Fuel Economy (FE) properties of this lubricating composition.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition includes greater than 50 wt. % of a base oil of lubricating viscosity, calcium, nitrogen, molybdenum and boron. The weight ratio of Ca:N (ppm/ppm) in the lubricating oil composition is greater than 1.3 to less than 3.0, the weight ratio of Ca:Mo (ppm/ppm) in the lubricating oil composition is greater than 6.7 to less than 56.3, and the weight ratio of Ca:B (ppm/ppm) in the lubricating oil composition is greater than 5.0 to less than 9.8. The lubricating oil composition does not contain added magnesium from a magnesium-containing detergent. The lubricating oil composition is resistant to deposit formation in the boosted internal combustion engine, as shown by its ability to ensure a TCO Temperature Increase of less than 9.0% as measured using the 2015 version of the General Motors dexos1® Turbocharger Coking Test.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition includes greater than 50 wt. % of a base oil of lubricating viscosity, calcium, nitrogen, molybdenum and boron. The weight ratio of Ca:N (ppm/ppm) in the lubricating oil composition is greater than 1.3 to less than 3.0, the weight ratio of Ca:Mo (ppm/ppm) in the lubricating oil composition is greater than 6.7 to less than 56.3, and the weight ratio of Ca:B (ppm/ppm) in the lubricating oil composition is greater than 5.0 to less than 9.8. The lubricating oil composition does not contain added magnesium from a magnesium-containing detergent. The lubricating oil composition is resistant to deposit formation in the boosted internal combustion engine, as shown by its ability to ensure a TCO Temperature Increase of less than 9.0% as measured using the 2015 version of the General Motors dexos1® Turbocharger Coking Test.

A lubricating oil composition including: a lubricant base oil; (A) a calcium salicylate detergent in an amount of 0.005 to 0.03 mass % in terms of calcium on the basis of the total mass of the composition; (B) a succinimide ashless dispersant in an amount of 0.005 to 0.25 mass % in terms of nitrogen on the basis of the total mass of the composition; (C) a nitrogen-containing antioxidant in an amount of 0.005 to 0.15 mass % in terms of nitrogen on the basis of the total mass of the composition; and optionally (D) a nitrogen-containing friction modifier in an amount of no more than 0.03 mass % in terms of nitrogen on the basis of the total mass of the composition, wherein a total content of any metallic detergent is 0.005 to 0.03 mass % in terms of metal on the basis of the total mass of the composition.

A lubricating oil composition including: a lubricant base oil; (A) a calcium salicylate detergent in an amount of 0.005 to 0.03 mass % in terms of calcium on the basis of the total mass of the composition; (B) a succinimide ashless dispersant in an amount of 0.005 to 0.25 mass % in terms of nitrogen on the basis of the total mass of the composition; (C) a nitrogen-containing antioxidant in an amount of 0.005 to 0.15 mass % in terms of nitrogen on the basis of the total mass of the composition; and optionally (D) a nitrogen-containing friction modifier in an amount of no more than 0.03 mass % in terms of nitrogen on the basis of the total mass of the composition, wherein a total content of any metallic detergent is 0.005 to 0.03 mass % in terms of metal on the basis of the total mass of the composition.

Disclosed is a lubricating oil composition containing a base oil, a viscosity index improver, a molybdenum-based friction modifier, a boron-containing dispersant, and at least two extreme-pressure additives selected from a sulfur-based extreme-pressure additive, a phosphorous-based extreme-pressure additive and a sulfur/phosphorus-based extreme-pressure additive, or a sulfur/phosphorus-based extreme-pressure additive. The base oil is a synthetic oil having a kinematic viscosity at 100° C. of 3 mm.sup.2/s or more and 10 mm.sup.2/s or less, the viscosity index improver is a resin having a number average molecular weight (Mn) of 1,000 or more and 10,000 or less, the mass ratio of boron atoms (B) contained in the boron-containing dispersant to molybdenum atoms (Mo) contained in the molybdenum-based friction modifier, [(B)/(Mo)] is 1 or more and 5 or less, and the mass ratio of sulfur atoms (S) to phosphorus atoms (P) contained in the extreme-pressure additive(s), [(S)/(P)] is 10 or more and 20 or less.

Disclosed is a lubricating oil composition containing a base oil, a viscosity index improver, a molybdenum-based friction modifier, a boron-containing dispersant, and at least two extreme-pressure additives selected from a sulfur-based extreme-pressure additive, a phosphorous-based extreme-pressure additive and a sulfur/phosphorus-based extreme-pressure additive, or a sulfur/phosphorus-based extreme-pressure additive. The base oil is a synthetic oil having a kinematic viscosity at 100° C. of 3 mm.sup.2/s or more and 10 mm.sup.2/s or less, the viscosity index improver is a resin having a number average molecular weight (Mn) of 1,000 or more and 10,000 or less, the mass ratio of boron atoms (B) contained in the boron-containing dispersant to molybdenum atoms (Mo) contained in the molybdenum-based friction modifier, [(B)/(Mo)] is 1 or more and 5 or less, and the mass ratio of sulfur atoms (S) to phosphorus atoms (P) contained in the extreme-pressure additive(s), [(S)/(P)] is 10 or more and 20 or less.