The present disclosure relates to polysiloxanes, processes for preparing polysiloxanes, and hydraulic fluids comprising polysiloxanes. This disclosure also relates to hydraulic fluids comprising one or more polysiloxane compounds and diphosphonate compounds, and to the use of diphosphonate compounds in hydraulic fluids or as additives or components in various compositions, for example to provide fire retardant properties to a fluid or composition. This disclosure also relates to use of the compositions as hydraulic fluids, which may be used in various machines, vehicles and craft, including aircraft.

The presently claimed invention relates to a gear oil composition having a kinematic viscosity at 40° C. in the range of ≥68 to ≤1000 cSt when measured in accordance with ASTM D445. The gear oil composition is useful as a lubricant in a gear box, especially in a wind turbine gear box.

The invention relates to a seal swell agent which is a substituted sulfonyldibenzene compound, and lubricating compositions containing the seal swell agent. The substituents on the benzene rings may be hydrocarbyl groups of 4 to 20 carbon atoms or alkylene groups of 1-2 carbon atoms with further functional groups.

Lubricating compositions comprising an azole-acrylic adduct formed by contacting an azole compound with an acrylic. The adduct formed has at least one nitrogen-alkyl group comprising at least one acyl. The lubricating composition also comprises an antiwear agent and an antioxidant. Methods of lubricating an internal combustion engine comprising contacting the internal combustion engine with the lubricating composition comprising an azole-acrylic adduct formed by contacting an azole compound with an acrylic. Methods of reducing corrosion and/or seal deterioration in an internal combustion engine. The use of an azole-acrylic adduct in a lubricating composition to reduce corrosion and/or seal deterioration in an internal combustion engine.

The present invention provides a lubricating oil composition for automatic transmissions which comprises: 55 to 85 mass % of a Fischer-Tropsch synthetic oil with a kinematic viscosity at 100° C. of 2 to 4 mm2/s as a low-viscosity base oil; 1 to 10 mass % of an olefin copolymer 5 with a kinematic viscosity at 100° C. of 150 to 1,000 mm2/s as a high-viscosity base oil; and a polymethacrylate with a weight-average molecular weight of 10,000 to 50,000. This lubricating oil composition is such that the viscosity index of the composition is not 10 less than 190, the Brookfield viscosity is not more than 6,000 mPa.Math.s at low temperature (−40° C.), the kinematic viscosity at 100° C. is 6 to 7 mm2/s, and the rate of reduction of the kinematic viscosity after a KRL shear stability test (60° C., 20 hr) is kept to within not more 15 than 3%.

Lubricating compositions comprising a mercaptoazole-acrylic adduct formed by contacting a mercaptoazole compound with an acrylic. The adduct formed has at least one sulfur-alkyl group comprising at least one acyl, or compounds having at least one nitrogen-alkyl group comprising at least one acyl, or mixtures thereof. The lubricating composition also comprises an antiwear agent and an antioxidant. Methods of lubricating an internal combustion engine comprising contacting the internal combustion engine with the lubricating composition comprising a mercaptoazole-acrylic adduct formed by contacting a mercaptoazole compound with an acrylic. Methods of reducing corrosion and/or seal deterioration in an internal combustion engine. The use of a mercaptoazole-acrylic adduct in a lubricating composition to reduce corrosion and/or seal deterioration in an internal combustion engine.

The invention provides a lubricant composition comprising an oil of lubricating viscosity and a protic acid salt of an N-hydrocarbyl-substituted gamma-(γ-) or delta-amino(thio)ester. The invention further relates to a method of lubricating a mechanical device with the lubricant composition.

Provided herein are polyolefin dispersants, as well as methods for producing polyolefin dispersants. The polyolefin dispersants can be defined by the formula below

##STR00001##

where R.sup.x is cationic initiator residue; R.sup.a is a polyolefin group; R.sup.1 and R.sup.2 are each, independently in each —(CR.sup.1R.sup.2) unit, H, alkyl, alkoxy, or alkylaryl; R.sup.3 and R.sup.4 are each, independently, H, alkyl, or alkoxy; m is an integer from 1 to 20; n is an integer from 1 to 6; r is an integer from 1 to 4; Y is a polyvalent amine linker comprising one or more tertiary amines, wherein the polyvalent amine linker does not include a primary amine or a secondary amine; and A is absent, or comprises a dispersive moiety.

The present invention relates to lubricating compositions and particularly gear oil compositions that include a specific class of substituted triazoles, where the substituted triazole includes at least one hydrocarbyl group linked to one of the nitrogen atoms in the triazole ring. Such compositions provide surprisingly good seal compatibility compared to compositions with other triazoles and/or alternative additives.

This invention provides a lubricating oil composition for automobile transmission that includes: as low-viscosity base oils: (i) between 45 and 95 mass % of a Fischer-Tropsch synthetic low-viscosity base oil with a 100° C. kinematic viscosity of between 1 mm.sup.2/s and 2 mm.sup.2/s, and between 0 and 25 mass % of other than a Fischer-Tropsch synthetic low-viscosity base oil with a 100° C. kinematic viscosity of between 1 mm.sup.2/s and 2 mm.sup.2/s, and (ii) between 0 and 35 mass % of a base oil wherein the 100° C. kinematic viscosity is greater that 2 mm.sup.2/s and no greater than 5 mm.sup.2/s; and (iii) between 5 and 55 mass % of an olefin polymer or copolymer, as a high-viscosity base oil, wherein the 100° C. kinematic viscosity is between 100 and 800 mm.sup.2/s. A lubricating oil composition for an automatic transmission wherein the 100° C. kinematic viscosity of this composition is between 3.8 and 5.5 mm.sup.2/s, the viscosity index is no less than 190, the flashpoint is no less than 140° C., and the reduction ratio of the 100° C. kinematic viscosity after shear stability testing, at 60° C. for 20 hours, is maintained at no greater than 3%.