Ethylene-C.sub.3-C.sub.10 alpha olefin copolymers, dispersants and lubricating oils/fuel compositions incorporating dispersants, and related methods are generally described herein. The copolymer may comprise ethylene-derived units and C.sub.3-C.sub.10 alpha-olefin-derived units. The C.sub.3-C.sub.10 alpha-olefin-derived units may have a carbon number from three to ten. For example, the C.sub.3-C.sub.10 alpha-olefin-derived units may be propylene-derived units. The dispersants may be made from copolymers having low metal and/or fluorine contents.

The invention relates to the use of a composition comprising a polyol ester-based lubricant and a refrigerant F comprising at least one tetrafluoropropene and at least one hydrofluorocarbon, in a heat transfer system containing a vapour compression circuit comprising an oil separator.

The present invention provides compounds of formula (I): wherein W is independently selected from the group consisting of H, F, Cl, Br and I; 10 X is independently selected from the group consisting of H, F, Cl, Br, I, CW.sub.3 and OR on the basis that at least one X is OR; R is independently selected from the group consisting of C(O) (CH.sub.2).sub.m(CF.sub.2).sub.nY and CW.sub.2C(CW.sub.2OC(O)(CH.sub.2)m(CF.sub.2)nY).sub.3; m is an integer from 0 to 2; 15 n is an integer from 2 to 8; Y is C(Z).sub.3; and Z is independently selected from the group consisting of H, F, Cl, Br and I. Such compounds may be utilised as lubricants, for example in heat transfer compositions.

The present invention provides a refrigerating machine oil comprising: a lubricating base oil; and 40 mass % or less of a polymer, based on a total amount of the refrigerating machine oil, the polymer having a structural unit represented by the following formula (I) and a weight average molecular weight of from 500 to 100000. ##STR00001## [In formula (I), R.sup.a, R.sup.b and R.sup.c each independently represents a hydrogen atom or a hydrocarbon group, and R.sup.d represents an oxygen-containing organic group or a C.sub.1-18 hydrocarbon group.]

The present invention relates to refrigerant compositions comprising at least one fluoroolefin, at least one lubricant and an effective amount of at least one inhibitor wherein the inhibitor is present in the fluoroolefin and the lubricant.

The present invention relates to a lubricating oil composition containing a base oil (A) and a viscosity index improver (B) such that in X-ray small-angle scattering spectra obtained through measurement at 40 C. and 100 C., a ratio [|(40)|/|(100)|] between |(40)| and |(100)|, each of which is an absolute value of a slope of a straight line calculated in a range of the scattering vector q as the x axis of from 0.1 nm .sup.1 to 1 nm .sup.by the least-squares method, is 1.5 or more.

A system may include an output manifold that may be in fluid communication with a reservoir and that may include multiple discharge ports. Each of the discharge ports may be configured to discharge electrorheological fluid into a housing. A recovery manifold may be in fluid communication with the reservoir and include multiple recovery ports. Each of the recovery ports may be configured to receive the electrorheological fluid from a housing. A gas remover may be positioned to extract gas from the electrorheological fluid received from the recovery ports. A housing may be connected to the system, and electrorheological fluid from the system may be pumped through the housing and the gas remover.

Compositions, systems and methods for introducing lubricants, and additives, that are designed to work with environmentally friendly refrigerants into vehicle heat management systems including passenger compartment air conditioning (A/C) systems are disclosed. Methods for charging lubricants and specific additives using environmentally desirable (low GWP) refrigerant or refrigerant blend compositions into an environmentally friendly system, such as a system that uses HFO-1234yf, are also disclosed.

Polyalkyl (meth)acrylates are useful in compressor oils. A method of increasing the energy efficiency of a compressor involves operating the compressor with a compressor oil containing a polyalkyl (meth)acrylate-based viscosity index improver.

A lubricating agent including an ionic liquid formed from a Bronsted acid (HX) and a Bronsted base (B), wherein the Bronsted base has a linear hydrocarbon group having 10 or more carbon atoms and the difference between the pKa value of the Bronsted acid in water and the pKa value of the Bronsted base in water is 12 or more.