Compositions resulting from the mixing of at least: a comb polydiol copolymer A1 and a compound A2 including at least two boronic ester functional groups, the comb polydiol copolymer A1 including a main chain and side chains, at least a portion of the side chains of the copolymer A1 being composed of oligomers. They exhibit very varied rheological properties depending on the proportion of the compounds A1 and A2 used. Composition resulting from the mixing of at least one lubricating oil with such a composition of associative and exchangeable polymers and use of this composition for lubricating a mechanical part.

Compositions resulting from the mixing of at least one oligomer A1, resulting from the copolymerization of at least one monomer functionalized by diol functions with at least a second monomer, and at least one compound A2 including at least two boronic ester functions. The compositions exhibit very varied rheological properties, depending on the proportion of the compounds A1 and A2 used. A composition also results from mixing at least one lubricating oil with such a composition of associative and exchangeable polymers, and to the use of this composition to lubricate a mechanical part.

A borate ester represented by the following formula: ##STR00001## where R.sup.1 is a hydrocarbon chain, R.sup.2 and R.sup.3 are independently either a hydrogen atom or a hydrocarbon chain, and m and n are independently from 1 to 5.

A product resulting from the reaction of at least: a hydroxybenzoic acid substituted by a hydrocarbyl group, a boron compound, and a quaternary ammonium salt. A lubricant composition including this product. Use of this product as a lubricant for two-stroke marine engines and four-stroke marine engines, more preferably two-stroke marine engines.

This invention relates to the use of a boron-containing additive in a non-aqueous lubricant composition as an inhibit or of lead corrosion associated with ashless, organic ester, anti-wear additives and/or friction modifiers.

The disclosed technology provides a method of lubricating a compression-ignition internal combustion engine with a maximum laden mass over 2,700 kg comprising supplying to the engine a lubricating composition comprising: an oil of lubricating viscosity, a 300 TBN or higher alkaline earth metal sulfonate detergent having a metal ratio of 10 to 40, an alkaline earth metal sulfonate detergent having a metal ratio of 3 to 9, and a TBN of 81 to 180 mg KOH/g, wherein the sulfonate detergents provide a total amount of sulfonate substrate of 1 wt % to 3 wt % of the lubricating composition, 0.1 to 1.2 wt % of antioxidant, wherein at least 20 wt % of the antioxidant is a phenolic antioxidant, a borated compound present in an amount to deliver 25 ppm to 300 ppm of boron, the lubricating composition has a sulfated ash content of 0.5 wt % to not more than 1.5 wt %, and the lubricating composition has a TBN of 6.5 to 15 mg KOH/g.

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 resulting from the mixing of at least: a comb polydiol copolymer A1 and a compound A2 including at least two boronic ester functional groups, the comb polydiol copolymer A1 including a main chain and side chains, at least a portion of the side chains of the copolymer A1 being composed of oligomers. They exhibit very varied rheological properties depending on the proportion of the compounds A1 and A2 used. Composition resulting from the mixing of at least one lubricating oil with such a composition of associative and exchangeable polymers and use of this composition for lubricating a mechanical part.

The disclosed technology relates to an automotive gear oil, which may be used, for example, in heavy duty manual transmissions and axles, and includes an oil of lubricating viscosity, 1 wt % or less of a dispersant, and at least one boron containing compound.

A borate ester represented by the following formula:

##STR00001##

where R.sup.1 is a hydrocarbon chain, R.sup.2 and R.sup.3 are independently either a hydrogen atom or a hydrocarbon chain, and m and n are independently from 1 to 5.