Lubricating compositions are described, the lubricating compositions comprising a base oil component and an additive component, wherein the additive component comprises a non-silicone anti-foaming agent.

Provided herein are compositions comprising at least one estolide compound of formula:

##STR00001##

in which n is an integer equal to or greater than 0; m is an integer equal to or greater than 1; R.sub.1, independently for each occurrence, is selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; R.sub.2 is selected from hydrogen and optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched; and R.sub.3 and R.sub.4, independently for each occurrence, are selected from optionally substituted alkyl that is saturated or unsaturated, and branched or unbranched. Also provided are uses of the compositions described herein.

A lubricating oil composition includes at least one base oil selected from the group consisting of a mineral oil-based lubricating oil, a synthetic oil-based lubricating oil, and a mixed oil thereof, zinc dialkyldithiophosphate X represented by Formula (1), and an acid phosphate ester amine salt Y represented by Formula (2), in which a content P.sub.X of the X is from 0.06% by mass to 0.08% by mass in terms of phosphorus concentration with respect to a total mass of the lubricating oil composition, and a content P.sub.Y of the Y is from 0.015% by mass to 0.025% by mass in terms of phosphorus concentration with respect to the total mass of the lubricating oil composition.

The incorporation of highly refined, low viscosity index base oils along with a polymeric thickener produces a final readily biodegradable fluid with a significantly high viscosity. The present invention allows the formulation of a high viscosity readily biodegradable fluid where the vast majority of the fluid is mineral oil. Previous uses of mineral oils only allowed for formulation of substantially lower viscosity readily biodegradable fluids.

The present invention is directed to the use of poly(polyisobutylenemethacrylate) as viscosity index improving component in lubricating oil compositions. The invention is further related to lubricating oil compositions comprising poly(polyisobutylenemethacrylate) with enhanced shear stability.

A multi-functional olefin copolymer viscosity index improver and a lubricating oil composition including such lubricant additive that provides improved viscometric properties and helps reduce low speed pre-ignition events at the same time. In one approach, the multi-functional olefin copolymer viscosity index improver is silicone functionalized and includes an acylated olefin copolymer with aminosilane or aminosiloxone pendant or side groups.

The present invention provides a hydraulic fluid comprising: (a) 40 to 2000 ppm by weight in terms of nitrogen content of a corrosion inhibiting agent which is one or more compounds of formula (I): ##STR00001## and/or tribologically acceptable salts thereof, wherein in formula (I): each R.sup.1 is independently a hydrocarbyl group comprising 1 to 10 carbon atoms, x is 0 to 4, each of R.sup.2 and R.sup.3 is independently hydrogen or a hydrocarbyl group comprising 1 to 20 carbon atoms, R.sup.4 is —NR.sup.5R.sup.6 or —OR.sup.7, each of R.sup.5 and R.sup.6 is independently an aryl group comprising 6 to 14 carbon atoms, optionally substituted with one or more hydrocarbyl groups comprising 1 to 20 carbon atoms, R.sup.7 is a hydrocarbyl group comprising 1 to 20 carbon atoms, and in each of said hydrocarbyl groups containing 2 or more carbon atoms, the carbon chain may, independently, optionally be interrupted by one or more ether groups; (b) 0.1 to 1% by weight of an ashless dispersant; and (c) a major amount of a base oil.

The invention relates to devices for purifying hydraulic and dielectric fluids (oils and fuels) of mechanical impurities and dissolved and dispersed water. It could be used in any fields where clean and contaminated fluids are used. The apparatus for reclaiming hydraulic and dielectric fluids comprises a vacuum tank with an atomizer, a vacuum pump, a dielectric fluid feed pump and dielectric fluid removal pump, all of said pumps being connected to the tank by pipes, and an electric filter, wherein the atomizer is disposed in the lower part of the vacuum tank, is arranged vertically with a spray member oriented upward and consists of a T fitting with a lower inlet for fluid and with a lateral inlet for air, a mixing chamber disposed above the T fitting, and a spray member with a nozzle, said spray member being disposed above the mixing chamber, and the electric filter comprises a housing with an inlet pipe and outlet pipe, a high-voltage power supply, a composite unit disposed inside the housing and consisting of current-carrying plates and dielectric spacers with apertures for current-carrying and heavy-duty fastening elements, a front plug and rear plug, and is current-carrying and heavy-duty fastening elements, wherein the surface of the current-carrying plates is provided with a porous ceramic dielectric coating. The technical result is increasing the efficiency of purifying and reclaiming dielectric fluids; increasing the useful volume of the vacuum tank without increasing the dimensions thereof; reducing the dispersivity of the fluid sprayed from the atomizer; simplifying the design; stabilizing the electromagnetic field of the electric filter; increasing the surface area of the electric filter by creating a developed surface of current-carrying filter elements without changing filter size and mass; improving reliability and ease of use; and reducing materials consumption.

Described herein are methods of stabilizing the beta hydrogen of glycerol based esters by the insertion of alkoxy groups to significantly improve the thermal, oxidative, and hydrolytic stability of the ester and allow for controlling the molar density of esters bonds in the lubricants to maximize hydrolytic stability while maintaining biodegradability and further improving performance properties.

The present invention aims to provide a viscosity-index improving agent having an excellent friction reduction effect to reduce friction of a lubricating oil composition when the viscosity-index improving agent is added thereto. The present also aims to provide a lubricating oil composition containing the viscosity-index improving agent. The present invention relates to, for example, a viscosity-index improving agent containing: (co)polymer (A) containing, as an essential constituent monomer, a polyolefin-based monomer (a) represented by the following formula (1); an ester oil (B1) having a kinematic viscosity at 100° C. of 1.00 to 2.50 mm.sup.2/s; and an ester oil (B2) having a kinematic viscosity at 100° C. of 2.51 to 5.00 mm.sup.2/s:

##STR00001##

wherein R.sup.1 is a hydrogen atom or a methyl group; —X.sup.1— is a group represented by —O—, —O(AO).sub.m-, or —NH—, A is a C2-C4 alkylene group, m is an integer of 1 to 10, and each A may be the same or different when m is 2 or more; R.sup.2 is a residue after removal of one hydrogen atom from a hydrocarbon polymer containing a 1,2-butylene group as a structural unit; and p represents a number of 0 or 1.