In some embodiments, ethylene-propylene random copolymers as viscosity modifiers were synthesized with pyridyldiamido catalyst systems and a chain transfer agent. In some embodiments, the present disclosure provides for ethylene-propylene random copolymers having an ethylene content between about 45 wt % and about 55 wt %. In some embodiments, the ethylene-propylene random copolymer is used as a viscosity modifier in a lubricating composition and a fuel composition.

A refrigerating machine oil containing: a lubricating base oil; and a compound represented by the following formula (1): ##STR00001## wherein R.sup.1 and R.sup.2 each independently represent a monovalent hydrocarbon group, R.sup.3 represents a divalent hydrocarbon group, and R.sup.4 represents hydrogen atom or a monovalent hydrocarbon group, and the refrigerating machine oil having a kinematic viscosity at 100° C. of 0.5 mm.sup.2/s or more and 2.5 mm.sup.2/s or less.

The present invention provides a class of halogen-containing synthetic base oils, and preparation method and use thereof. The synthetic base oils have introduced with halogen, especially fluorine, wherein the dipole motion of the halogen groups results in dipole interaction between the dipoles of other components and the base oil molecules of dipole-dipole and dipole-induced halogen (especially fluorine), and the interaction force is stronger and more localized than the dispersion force between the molecules of pure hydrocarbon synthetic oils, and thus the performance of the base oils is directly affected. It solved the problem of oil solubility of pure hydrocarbon synthetic oils, and also improved the properties of oxidation resistance and thermal stability.

A lubricating oil composition excellent in the wear resistance and a refrigerator oil composition excellent in the oxidation stability using the lubricating oil composition are provided by a lubricating oil composition containing a base oil (A) and a phosphine derivative (B) having one or more oxygen atom in a molecule.

The invention relates to the use of at least one phosphorus compound, which is free of sulfur and has no amine function, as an anti-wear and extreme-pressure additive in a lubricant composition for a propulsion system of an electric or hybrid vehicle. The invention also relates to the use of a lubricant composition comprising at least one phosphorus compound, which is free of sulfur and has no amine function, as an anti-wear and extreme-pressure additive, for lubricating and optionally cooling a propulsion system of an electric or hybrid vehicle, in particular for lubricating and cooling the electric motor and the power electronics of an electric or hybrid vehicle.

The present invention provides a refrigerating machine oil comprising a hydrocarbon-based base oil having a viscosity index of 120 or less, and the refrigerating machine oil being used with a 1-chloro-2,3,3,3-tetrafluoropropene refrigerant.

A lubricating oil composition may be suitable for a refrigerator and have excellent thermal stability when used with a refrigerant using difluoromethane (R32), trifluoroiodomethane (CF.sub.3I), and at least one selected from saturated fluorinated hydrocarbon compounds (HFC) other than difluoromethane (R32). Such compositions may include: a base oil (A) with at least one selected from a polyoxyalkylene glycol, a polyvinyl ether, a copolymer of a poly(oxy)alkylene glycol or a monoether thereof and a polyvinyl ether, and a polyol ester; and an aliphatic epoxy compound (B), wherein the content of the aliphatic epoxy compound (B) is more than 2.0% by mass based on the total amount of the lubricating oil composition.

The present invention relates to a hydraulic fluid composition containing a base oil (A), an antioxidant (B) including an amine-based antioxidant (B1) and a phenol-based antioxidant (B2), and a succinimide-based compound (C), wherein the hydraulic fluid composition satisfies the following requirement (I); and is to be used for hydraulic equipment which is equipped with at least one of a wet type brake and a wet type clutch and which is selected from a construction machinery, a general industrial machinery, and a power generator, and in which a working pressure is 30 MPa or more. The hydraulic fluid composition is not only excellent in wear resistance and an effect for suppressing the sludge formation but also excellent in a braking performance or a clutch performance, even when used under a high-pressure condition. Requirement (I): A static friction coefficient (μ.sub.s) after 1,000 cycles, as measured in conformity with the SAE No. 2 test described in JCMAS P 047:2004, is 0.100 to 0.162.

A refrigerating oil comprising a lubricating base oil, a first extreme pressure agent containing sulfur and phosphorus as constituent elements and a second extreme pressure agent containing phosphorus but not containing sulfur as constituent elements, and having a kinematic viscosity at 100° C. of 0.5 mm.sup.2/s or more and 2.5 mm.sup.2/s or less.

The present invention relates to heat transfer compositions comprising refrigerant, lubricant and stabilizer, wherein the refrigerant comprises from about 10% by weight to 100% by weight of trifluoroiodomethane (CF.sub.3I), and wherein said lubricant comprises polyol ester (POE) lubricant and/or polyvinyl ether (PVE) lubricant, and wherein said stabilizer comprises at least one stabilizing compound according to the following Formula I:

##STR00001##

where each R.sup.1 is independently an epoxy terminated ethoxy, propoxy or butoxy group.