GER fluids are improved by the addition of a polar molecule additive. By addition of a polar molecule additive, yield stresses under electric field are improved by over 50% while the current density is reduced to less than a quarter of the original GER. The reversible response time still remains the same, and the sedimentation stability is greatly enhanced. The zero field viscosity of the modified GER fluid remains the same as that of the original GER fluid without the additive. The improved GER characteristics improve general functionality as an electrical-mechanical interface, attendant with applications to car clutches, fluid brakes, and vehicle shock absorbers.

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.

This vibration damping device (10) includes a magnetorheological fluid composition in a cylinder (12). The magnetorheological fluid composition includes magnetic particles; a dispersant having the magnetic particles dispersed therein; and a friction modifier. The friction modifier is an amine-based additive having a hydrocarbon chain having 14 to 22 carbon atoms, preferably an alkyl chain or an alkenyl chain. The content of the friction modifier is 0.1 to 5 mass %.

Dispersions are prepared by dispersing a polymer precursor such as a polyol into a non-aqueous fluid. The resulting droplets of the polymer precursor is partially polymerized to produce liquid or partially gelled droplets, and then sized to a target particle size. The sized particles are then cured to form solid particles. The process allows for close control of particle size, allows for good control of temperature, and is amenable to batch, semi-continuous or even continuous operation. The resulting dispersions are useful as electrorheological fluids.

Provided is a lubricating oil composition for a transmission having excellent gear properties, clutch properties, cooling properties, and electric insulating properties. The lubricating oil composition for a transmission preparing by blending (A) a base oil, (B) a viscosity index improver having a mass average molecular weight of 10,000 to 50,000, and (C-1) a polyamide and/or (C-2) a polyol ester, the base oil (A) including (A-1) a synthetic oil having a kinematic viscosity at 100 C. of 1.0 to 10.0 mm.sup.2/s.

An electrorheological composition has corrosion-inhibiting properties and contains at least one organic ionic compound as an electrolyte. Also disclosed are methods for the production thereof and the use thereof.

Provided is an electro-rheological fluid, including: a fluid having an insulating property; and a polyether-based polyurethane particle containing a metal ion, wherein the polyurethane particle contains a chain extender, wherein the metal ion includes at least a Li ion, and wherein a ratio ([Li]/[O]) of a molar concentration ([Li]) of the Li ion to a molar concentration ([O]) of oxygen atoms of ether groups in the polyurethane particles satisfies the following condition: [Ratio of molar concentration ([Li]) of Li ion to molar concentration ([O]) of oxygen of ether groups] [Li]/[O]9.010.sup.5.

Provided herein are dielectric fluids 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 herein are uses of dielectric fluids and electrical devices such as transformers that comprise a dielectric fluid comprising at least one estolide compound.

There has been a demand for a lubricating oil composition that has excellent cooling performance and insulating properties. This lubricating oil composition contains a base oil (A), solid particles (B) that have an average primary particle diameter of 500 nm or less, and a dispersant (C); the content of the solid particles (B) is 0.1 to 30% by mass based on the total amount of the lubricating oil composition; and the content of the dispersant (C) is 0.1 to 20% by mass based on the total amount of the lubricating oil composition.