Low molecular weight polyalkyl acrylate polymers can be used as high viscosity base fluids. A corresponding method can be used for their preparation. Lubricant compositions may contain such low molecular weight polyalkyl acrylate polymers and the compositions may be used as automatic transmission fluids, manual transmission fluids, continuously variable transmission fluids, gear oil formulations, industrial gear oil formulations, axle fluid formulations, dual clutch transmission fluids, dedicated hybrid transmission fluids, or hydraulic oils.

The invention relates to the use of calcium complex and calcium sulfate complex lubricating grease compositions as lubricants for wire ropes. The invention further relates to a method for producing the wire ropes and to wire ropes provided with the lubricating grease composition.

A viscosity index improver comprising a polymer which has a high viscosity index and good shear stability and which exhibits sufficient solubility in a lubricating base oil, a process for producing the same, and a lubricating oil composition containing the viscosity index improver are provided, wherein the viscosity index improver comprising a polymer satisfying the following (1) to (4): (1) weight-average molecular weight (Mw) of 200,000 or more and 600,000 or less; (2) number-average molecular weight (Mn) of 90,000 or more; (3) molecular weight distribution (Mw/Mn) of 4.0 or less; and (4) branching degree of 1.0 or more.

This application relates to copolymer compositions and copolymerization processes, as well as to lubricating oil compositions comprising such copolymer compositions as viscosity index improvers, and base oil. The copolymer compositions may be made using 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). Lubricating oil compositions comprising such copolymer compositions may exhibit superior viscosity properties.

A block copolymer comprising a PAO block derived from alpha-olefin monomer(s) having a carbon backbone comprising more than six (6) carbon atoms per molecule and a poly(alkyl methacrylate) block derived from alkyl methacrylate monomer(s) having an alkyl group comprising at least six (6) carbon atoms forms micelles in hydrocarbon solvents and lubricant oil base stocks with large space volume even at low overall molecular weight. The block copolymer of this disclosure is particularly advantageous as viscosity modifier for lubricant oil compositions.

The invention provides a lubricating oil composition for automatic transmissions is made such that it comprises proportionately as its main constituents: 60 to 98 mass % as low viscosity base oils being base oils belonging to Groups 2 to 4 of the API (American Petroleum Institute) base oil categories wherein the kinematic viscosity at 100 C. is 2 to 5 mm.sup.2/s (Fischer-Tropsch synthetic oil comprising at least 45 to 80 mass %); 1 to 20 mass % as high-viscosity base oils being metallocene/poly--olefins with a kinematic viscosity at 100 C. of 100 to 600 mm.sup.2/s; and 1 to 20 mass % being a polymethacrylate with a weight-average molecular weight of 10,000 to 50,000. The viscosity index of this composition is not less than 190, the Brookfield viscosity at 40 C. is not more than 5000 mPa.Math.s, the 100 C. kinematic viscosity is 5 to 7 mm.sup.2/s, and the rate of reduction of the 100 C. kinematic viscosity after a KRL shear stability test (60 C., 20 hr) is not more than 3%.

raction fluid additive combination that is usable with any traction fluids base stock is provided. To optimize the traction, low temperature viscosity and shear stability performance, a combination of a polyisobutene and a polymethacrylate may be added to a base oil to obtain a traction fluid with good low temperature viscosity without degrading the shear strength properties of the fluid. To minimize foaming of the traction fluid, a combination of one, two, or more anti-foaming agents may be added to the fluid in addition to a standard additive package.

A lubricating composition comprises an oil-soluble poly(2-oxazoline) additive having the repeat unit:
N(COR.sup.1)CH.sub.2CH.sub.2 where the number of repeat units (n) is an integer between 4 and 1000; where the polymer carries an inorganic or organic nucleophilic polymerization terminating group t, and a linear, branched or cyclic hydrocarbyl polymerization initiator group (i); and where R.sup.1 comprises a single or a mixture of linear branched or cyclic hydrocarbyl groups having 1-100 carbon atoms, some or all having 12-100 carbon atoms, or of at least one macro-monomeric hydrocarbyl group with more than 50 carbon atoms provided that when the polymer is a homopolymer and R.sup.1 lacks any hetero atoms; (A) i has a molecular weight of less than 250 g/mol, and R.sup.1 has an average number of carbon atoms of 12 to 50; or (B) n is greater than 15. The polymer may provide the composition, in the form of a lubricant, with friction modifier, and with low impact on lubricant viscosity. The polymer may be a homopolymer, a block copolymer or a star polymer.

The invention provides a lubricating oil composition being a lubricating oil composition containing a base oil composition which includes a lubricant base oil belonging to Group 3 of the base oil categories specified by the American Petroleum Institute (API) and a comb-like polymethacrylate-based viscosity index improver wherein the weight-halving temperature is not less than 310 C., and the sulphur content in the aforementioned lubricating oil composition is not more than 0.3 weight % in terms of the total weight of the aforementioned lubricating oil composition, and the aforementioned lubricating oil composition has an SAE viscosity grade of 0W-20, 5W-20 or 5W-30, a viscosity index of not less than 185 and a high-temperature high-shear viscosity at 100 C. of not more than 7.5 mPa.Math.s.

Disclosed is a lubricant composition including: at least one base oil; at least one polyalkylene glycol with at least 50% by weight of butylene oxide units and having a kinematic viscosity, measured at 100 C. according to standard ASTM D445 (2015), which is greater than or equal to 50 mm2/s, a kinematic viscosity, measured at 40 C. according to standard ASTM D445 (2015), which is greater than or equal to 1000 mm2/s and a Viscosity Index, measured according to standard ASTM D2270 (2012), which is greater than or equal to 180. Also disclosed is the use of such a composition for transmission or gear lubrication.