Provided are 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. Also provided are methods of tuning or adjusting TE and/or SSI of bimodal copolymer compositions, especially ethylene copolymer compositions, by adjusting melt flow rate (MFR), corrected melt flow rate ratio (cMFRR), and/or intra-fractional melt flow rate ratio (IFMFRR) of the copolymer composition in order to obtain an adjusted copolymer composition exhibiting adjusted TE and/or SSI. Such methods provide excellent flexibility in rheology modifier production campaigns targeting different TE and/or SSI values.

Provided are 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. Also provided are methods of tuning or adjusting TE and/or SSI of bimodal copolymer compositions, especially ethylene copolymer compositions, by adjusting melt flow rate (MFR), corrected melt flow rate ratio (cMFRR), and/or intra-fractional melt flow rate ratio (IFMFRR) of the copolymer composition in order to obtain an adjusted copolymer composition exhibiting adjusted TE and/or SSI. Such methods provide excellent flexibility in rheology modifier production campaigns targeting different TE and/or SSI values.

A lubricant composition is prepared having a base oil composition and an additive composition comprising a molybdenum dialkyldithiocarbamate and an organic friction modifier such as an oil-soluble mono-, di- or tri-glyceride of at least one hydroxyl polycarboxylic acid, or a derivative thereof may, especially when used in combination with a base oil composition of a functionally modified poly-alpha-olefin (e.g. alpha-olefin and ester copolymer), a poly-alpha-olefin and optionally an additive carrier such as an alkylated naphthalene. The lubricant composition of the present invention finds particular application as a lubricant composition for robotics and robotic gearboxes, industrial gears and wind turbine gears and especially for gearboxes having a rolling element (such as a spherical bearing or a cylindrical bearing). It provides enhanced longevity, good elastomer compatibility and good anti-wear properties. Embodiments of the invention also demonstrate excellent protection against leaks and sludge.

A lubricant composition is prepared having a base oil composition and an additive composition comprising a molybdenum dialkyldithiocarbamate and an organic friction modifier such as an oil-soluble mono-, di- or tri-glyceride of at least one hydroxyl polycarboxylic acid, or a derivative thereof may, especially when used in combination with a base oil composition of a functionally modified poly-alpha-olefin (e.g. alpha-olefin and ester copolymer), a poly-alpha-olefin and optionally an additive carrier such as an alkylated naphthalene. The lubricant composition of the present invention finds particular application as a lubricant composition for robotics and robotic gearboxes, industrial gears and wind turbine gears and especially for gearboxes having a rolling element (such as a spherical bearing or a cylindrical bearing). It provides enhanced longevity, good elastomer compatibility and good anti-wear properties. Embodiments of the invention also demonstrate excellent protection against leaks and sludge.

This application relates to copolymer compositions and copolymerization processes. The processes may use two different metallocene catalysts: one capable of producing high molecular weight copolymers; and one suitable for producing lower molecular weight copolymers having at least a portion of vinyl terminations, and the copolymer compositions produced thereby. Copolymer compositions may comprise (1) a first ethylene copolymer fraction having high molecular weight, exhibiting branching topology, and having relatively lower ethylene content (based on the weight of the first ethylene copolymer fraction); and (2) a second ethylene copolymer fraction having low molecular weight, exhibiting linear rheology, and having relatively higher ethylene content (based on the weight of the second ethylene copolymer fraction). It is believed that the unique combination of these properties provides a copolymer composition with advantageous viscosity modifying properties, such as an excellent combination of shear thinning and fuel economy, as well as high thickening efficiency.

This application relates to copolymer compositions and copolymerization processes. The processes may use two different metallocene catalysts: one capable of producing high molecular weight copolymers; and one suitable for producing lower molecular weight copolymers having at least a portion of vinyl terminations, and the copolymer compositions produced thereby. Copolymer compositions may comprise (1) a first ethylene copolymer fraction having high molecular weight, exhibiting branching topology, and having relatively lower ethylene content (based on the weight of the first ethylene copolymer fraction); and (2) a second ethylene copolymer fraction having low molecular weight, exhibiting linear rheology, and having relatively higher ethylene content (based on the weight of the second ethylene copolymer fraction). It is believed that the unique combination of these properties provides a copolymer composition with advantageous viscosity modifying properties, such as an excellent combination of shear thinning and fuel economy, as well as high thickening efficiency.

A lubricating composition suited to use for lubricating a hydraulic system includes an oil of lubricating viscosity and a compound comprising a polyolefin-substituted bridged hydroxyaromatic compound or metal salt thereof, wherein the wherein the polyolefin is derived from a isobutylene having a number average molecular weight of 150 to 800.

An automatic transmission oil composition includes 80 to 85 wt % of a base oil, 1 to 5 wt % of metallocene polyalphaolefin, 1 to 5 wt % of a detergent-dispersant, 0.01 to 0.03 wt % of a trinuclear molybdenum-based dialkyldithiocarbamate friction modifier, 3 to 10 wt % of a viscosity modifier, and 3 to 5 wt % of an anti-wear additive. The automatic transmission oil composition is prepared by mixing base oil with metallocene polyalphaolefin and a trinuclear molybdenum-based dialkyldithiocarbamate friction modifier at specific mixing ratios, whereby the dynamic friction coefficient can be maintained at an equivalent level and the metal friction coefficient can be reduced, thus improving the power transfer efficiency between transmission metals and fuel economy (an improvement of 1.5% or more), increasing durability, and minimizing energy loss.

An automatic transmission oil composition includes 80 to 85 wt % of a base oil, 1 to 5 wt % of metallocene polyalphaolefin, 1 to 5 wt % of a detergent-dispersant, 0.01 to 0.03 wt % of a trinuclear molybdenum-based dialkyldithiocarbamate friction modifier, 3 to 10 wt % of a viscosity modifier, and 3 to 5 wt % of an anti-wear additive. The automatic transmission oil composition is prepared by mixing base oil with metallocene polyalphaolefin and a trinuclear molybdenum-based dialkyldithiocarbamate friction modifier at specific mixing ratios, whereby the dynamic friction coefficient can be maintained at an equivalent level and the metal friction coefficient can be reduced, thus improving the power transfer efficiency between transmission metals and fuel economy (an improvement of 1.5% or more), increasing durability, and minimizing energy loss.

The present invention relates to copolymers, to a method for the preparation of these copolymers, to the use of these copolymers for reducing wear in a lubricant composition, to lubricant compositions comprising these copolymers, and to the use of these lubricant compositions as an automatic transmission fluid, a continuously variable transmission fluid, an engine oil, a gear oil, or a hydraulic oil.