Hydrogenated polymers with a radial structure having a core made up of calixarenes of the general formula (I), to the core of which is linked a number P of hydrogenated linear polymer segments selected from: —hydrogenated homopolymers or co-polymers of conjugated dienes; or—hydrogenated co-polymers of said conjugated dienes and monoalkenyl arenes, and—mixtures thereof said formula (I) in which: —R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected from hydrogen; a group containing carbon and hydrogen; a group also containing heteroatoms in addition to carbon and hydrogen; a group also containing silicon in addition to carbon, hydrogen and heteroatoms; —one of the two substituents R.sub.5 and R.sub.6 is hydrogen, while the other may be hydrogen or alkyl, with a number of carbon atoms between 1 and 6, preferably methyl and ethyl; —n is an integer in the range between 4 and 16. ##STR00001##

Hydrogenated polymers with a radial structure having a core made up of calixarenes of the general formula (I), to the core of which is linked a number P of hydrogenated linear polymer segments selected from: —hydrogenated homopolymers or co-polymers of conjugated dienes; or—hydrogenated co-polymers of said conjugated dienes and monoalkenyl arenes, and—mixtures thereof said formula (I) in which: —R.sub.1, R.sub.2, R.sub.3 and R.sub.4 are independently selected from hydrogen; a group containing carbon and hydrogen; a group also containing heteroatoms in addition to carbon and hydrogen; a group also containing silicon in addition to carbon, hydrogen and heteroatoms; —one of the two substituents R.sub.5 and R.sub.6 is hydrogen, while the other may be hydrogen or alkyl, with a number of carbon atoms between 1 and 6, preferably methyl and ethyl; —n is an integer in the range between 4 and 16. ##STR00001##

The invention provides lubricating composition comprising: an oil of lubricating viscosity, and an oxyalkylated hydrocarbyl phenol, wherein the oxyalkylated hydrocarbyl phenol is substituted with at least one aliphatic hydrocarbyl group of 40 to 96 carbon atoms, and wherein the oxyalkylated hydrocarbyl phenol is substantially free of aromatic hydrocarbyl groups. The invention further relates to a method of lubricating a mechanical device (such as an internal combustion engine) with the lubricating composition. The invention further relates to the use of the oxyalkylated hydrocarbyl phenol in the lubricating composition to a passenger car internal combustion engine at least one of (i) control of fuel economy, (ii) control of corrosion, (iii) cleanliness, and (iv) control of bore wear.

The invention provides lubricating composition comprising: an oil of lubricating viscosity, and an oxyalkylated hydrocarbyl phenol, wherein the oxyalkylated hydrocarbyl phenol is substituted with at least one aliphatic hydrocarbyl group of 40 to 96 carbon atoms, and wherein the oxyalkylated hydrocarbyl phenol is substantially free of aromatic hydrocarbyl groups. The invention further relates to a method of lubricating a mechanical device (such as an internal combustion engine) with the lubricating composition. The invention further relates to the use of the oxyalkylated hydrocarbyl phenol in the lubricating composition to a passenger car internal combustion engine at least one of (i) control of fuel economy, (ii) control of corrosion, (iii) cleanliness, and (iv) control of bore wear.

The present invention relates to the field of multipurpose lubricants which may be used in the various components of automotive vehicles, notably in the engine, the transmission or the hydraulic circuit.

The invention relates to the use of at least one polymer which improves the viscosity index, chosen from hydrogenated copolymers of diene and of aromatic vinyl, in a lubricant composition for decreasing the viscosity of said lubricant composition in the course of the use of said lubricant composition during the lubrication of the various components of an industrial vehicle, notably of a diesel engine industrial vehicle, such as the engine, the gearbox and the hydraulic circuit, said lubricant composition undergoing at least one thermal shear during its use.

The present invention relates to the field of multipurpose lubricants which may be used in the various components of automotive vehicles, notably in the engine, the transmission or the hydraulic circuit.

The invention relates to the use of at least one polymer which improves the viscosity index, chosen from hydrogenated copolymers of diene and of aromatic vinyl, in a lubricant composition for decreasing the viscosity of said lubricant composition in the course of the use of said lubricant composition during the lubrication of the various components of an industrial vehicle, notably of a diesel engine industrial vehicle, such as the engine, the gearbox and the hydraulic circuit, said lubricant composition undergoing at least one thermal shear during its use.

A VM concentrate comprising: from about 60 to about 95 parts (and at least 50 wt %) of a diluent oil (e.g., having a KV100 of about 2 cSt to about 40 cSt); and from about 5 parts to about 40 parts (and at least 6.0 wt %) of a linear triblock copolymer characterized by the formula: D′-PA-D″; wherein D′ represents a block derived from diene, PA represents a block derived from monoalkenyl arene, D″ represents a block derived from diene, and the linear triblock copolymer is present in an amount effective to modify a lubricating kinematic viscosity at approximately 100° C. (KV100) of the concentrate, and wherein the KV100 of the concentrate is about 3000 cSt or less. The linear triblock copolymer may additionally or alternatively have a thickening efficiency span of at most 0.5.

A VM concentrate comprising: from about 60 to about 95 parts (and at least 50 wt %) of a diluent oil (e.g., having a KV100 of about 2 cSt to about 40 cSt); and from about 5 parts to about 40 parts (and at least 6.0 wt %) of a linear triblock copolymer characterized by the formula: D′-PA-D″; wherein D′ represents a block derived from diene, PA represents a block derived from monoalkenyl arene, D″ represents a block derived from diene, and the linear triblock copolymer is present in an amount effective to modify a lubricating kinematic viscosity at approximately 100° C. (KV100) of the concentrate, and wherein the KV100 of the concentrate is about 3000 cSt or less. The linear triblock copolymer may additionally or alternatively have a thickening efficiency span of at most 0.5.

A comb copolymer viscosity modifier may be made by polymerization comprising at least, or consisting essentially of, the following monomers: (a) a hydrogenated polybutadiene-based (alk)acrylate ester macromonomer (which repeat units may comprise from 7.0 wt % to 18 wt % of the repeat units of the comb copolymer viscosity modifier); (b) a C.sub.3-C.sub.8 alkyl (alk)acrylate ester monomer (which repeat units may comprise from 40 wt % to 71 wt % or from 45 wt % to 64 wt % of the repeat units of the comb copolymer viscosity modifier); and (c) a C.sub.12-C.sub.24 alkyl (alk)acrylate ester monomer, wherein repeat units based on the C.sub.12-C.sub.24 alkyl (alk)acrylate ester monomer comprise at least 21.0 wt % (and optionally up to 35.0 wt %) of repeat units of the comb copolymer viscosity modifier. Lubricant compositions comprising the comb copolymer viscosity modifier, as well as uses thereof and methods for modifying viscosity, are also contemplated herein.

A comb copolymer viscosity modifier may be made by polymerization comprising at least, or consisting essentially of, the following monomers: (a) a hydrogenated polybutadiene-based (alk)acrylate ester macromonomer (which repeat units may comprise from 7.0 wt % to 18 wt % of the repeat units of the comb copolymer viscosity modifier); (b) a C.sub.3-C.sub.8 alkyl (alk)acrylate ester monomer (which repeat units may comprise from 40 wt % to 71 wt % or from 45 wt % to 64 wt % of the repeat units of the comb copolymer viscosity modifier); and (c) a C.sub.12-C.sub.24 alkyl (alk)acrylate ester monomer, wherein repeat units based on the C.sub.12-C.sub.24 alkyl (alk)acrylate ester monomer comprise at least 21.0 wt % (and optionally up to 35.0 wt %) of repeat units of the comb copolymer viscosity modifier. Lubricant compositions comprising the comb copolymer viscosity modifier, as well as uses thereof and methods for modifying viscosity, are also contemplated herein.