Lubricating oil compositions are provided which contain bimodal copolymer compositions, and in particular bimodal ethylene--olefin copolymer compositions. The copolymer compositions comprise first and second ethylene--olefin copolymer components. The bimodal compositions are particularly useful as viscosity or rheology modifiers, e.g., in lubricating oil compositions. Lubricating oil compositions comprising the copolymer compositions advantageously exhibit enhanced shear stability index (SSI) and thickening efficiency (TE) values, while maintaining excellent low-temperature properties such as pour point, mini-rotary viscometer viscosity, and cold crank simulation performance.

Lubricating oil compositions are provided which contain bimodal copolymer compositions, and in particular bimodal ethylene--olefin copolymer compositions. The copolymer compositions comprise first and second ethylene--olefin copolymer components. The bimodal compositions are particularly useful as viscosity or rheology modifiers, e.g., in lubricating oil compositions. Lubricating oil compositions comprising the copolymer compositions advantageously exhibit enhanced shear stability index (SSI) and thickening efficiency (TE) values, while maintaining excellent low-temperature properties such as pour point, mini-rotary viscometer viscosity, and cold crank simulation performance.

Lubricating oil compositions are provided which contain bimodal copolymer compositions, and in particular bimodal ethylene--olefin copolymer compositions. The copolymer compositions comprise first and second ethylene--olefin copolymer components. The bimodal compositions are particularly useful as viscosity or rheology modifiers, e.g., in lubricating oil compositions. Lubricating oil compositions comprising the copolymer compositions advantageously exhibit enhanced shear stability index (SSI) and thickening efficiency (TE) values, while maintaining excellent low-temperature properties such as pour point, mini-rotary viscometer viscosity, and cold crank simulation performance.

Lubricating oil compositions are provided which contain bimodal copolymer compositions, and in particular bimodal ethylene--olefin copolymer compositions. The copolymer compositions comprise first and second ethylene--olefin copolymer components. The bimodal compositions are particularly useful as viscosity or rheology modifiers, e.g., in lubricating oil compositions. Lubricating oil compositions comprising the copolymer compositions advantageously exhibit enhanced shear stability index (SSI) and thickening efficiency (TE) values, while maintaining excellent low-temperature properties such as pour point, mini-rotary viscometer viscosity, and cold crank simulation performance.

The present invention relates to a comb copolymer comprising in polymerized form up to 40 wt % of a PIB macromonomer of the formula (I) and a hydrophobic monomer of the formula (II). The invention further relates to a method of preparing the PIB macromonomer of the formula (I) where a polyisobutene amine of the formula (IV) is reacted with (meth)acrylic acid anhydride; and to a lubricant comprising a base oil, the comb copolymer, and further lubricant additives; and to a use of the comb copolymer for improving the viscosity index of a lubricating oil.

The present invention relates to a comb copolymer comprising in polymerized form up to 40 wt % of a PIB macromonomer of the formula (I) and a hydrophobic monomer of the formula (II). The invention further relates to a method of preparing the PIB macromonomer of the formula (I) where a polyisobutene amine of the formula (IV) is reacted with (meth)acrylic acid anhydride; and to a lubricant comprising a base oil, the comb copolymer, and further lubricant additives; and to a use of the comb copolymer for improving the viscosity index of a lubricating oil.

Provided herein are compositions comprising at least one estolide compound of formula: ##STR00001##
in which n is an integer equal to or greater than 0; m is an integer equal to or greater than 1; R.sub.1, independently for each occurrence, is selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; R.sub.2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R.sub.3 and R.sub.4, independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched. Also provided are uses of the compositions described herein.

Provided herein are compositions comprising at least one estolide compound of formula:

##STR00001##

in which n is an integer equal to or greater than 0; m is an integer equal to or greater than 1; R.sub.1, independently for each occurrence, is selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; R.sub.2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R.sub.3 and R.sub.4, independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched. Also provided are uses of the compositions described herein.

Provided are a viscosity modifier for lubricating oils for obtaining an additive composition for lubricating oils having excellent fluidity in a wide temperature range from low temperature to high temperature; and said additive composition for lubricating oils. Further provided are a viscosity modifier for lubricating oils for obtaining a lubricating oil composition capable of reducing viscosity in good balance in a wide temperature range from low temperature to high temperature; and said lubricating oil composition. The viscosity modifier for lubricating oils includes an ethylene -olefin copolymer (A) which includes 30 to 50 mole % of structural units derived from at least one -olefin selected from -olefins having 4 and 5 carbon atoms and 50 to 70 mole % of structural units derived from ethylene (with the proviso that the total of all structural units of said copolymer is 100 mole %) and which satisfies specific requirements (a), (b), and (c).

Provided are a viscosity modifier for lubricating oils for obtaining an additive composition for lubricating oils having excellent fluidity in a wide temperature range from low temperature to high temperature; and said additive composition for lubricating oils. Further provided are a viscosity modifier for lubricating oils for obtaining a lubricating oil composition capable of reducing viscosity in good balance in a wide temperature range from low temperature to high temperature; and said lubricating oil composition. The viscosity modifier for lubricating oils includes an ethylene -olefin copolymer (A) which includes 30 to 50 mole % of structural units derived from at least one -olefin selected from -olefins having 4 and 5 carbon atoms and 50 to 70 mole % of structural units derived from ethylene (with the proviso that the total of all structural units of said copolymer is 100 mole %) and which satisfies specific requirements (a), (b), and (c).