51results about How to "High shear stability" patented technology

The invention relates to composite core-shell particles wherein the core is a porous, carbon-based matrix which contains silicon particles enclosed in pores of the matrix; the pores containing the silicon particles have a diameter of not less than 60 nm as determined by scanning electron microscopy (SEM); the shell can be obtained by carbonizing one or more carbon precursors selected from among the group comprising tars, pitches, hard carbon, soft carbon and hydrocarbons having 1 to 20 carbon atoms, resulting in a non-porous shell.

An aqueous dispersion composition of about 30 to about 70 weight % non-melt-processible fluoropolymer particles having a standard specific gravity (SSG) of less than 2.225 and about 2 to about 11 weight % surfactant based on the weight of said fluoropolymer comprising a compound or mixture of compounds of the formula: R(OCH2CH2)nOH wherein R is a branched alkyl, branched alkenyl, cycloalkyl, or cycloalkenyl hydrocarbon group having 8-18 carbon atoms and n is an average value of 5 to 18. The fluoropolymer particles of the dispersion comprise a core of high molecular weight polytetrafluoroethylene and a shell of lower molecular weight polytetrafluoroethylene or modified polytetrafluoroethylene. Preferably, the aqueous dispersion composition comprises about 45 to about 65 weight % non-melt-processible fluoropolymer particles.

Powder slurries and powder coatings which can be produced in the presence of an emulsifier (A), wherein (1) a liquid component (B) containing a liquid or liquefied constituent of a powder slurry or a powder coating is emulsified in an aqueous medium (C) to give an aqueous emulsion of liquid particles (D), (2) the emulsion is allowed to cool so that a suspension of dimensionally stable particles (D), i.e. the powder slurry, is formed and (3) the dimensionally stable particles (D), i.e. the powder coating, are isolated, with the emulsifier (A) having a hydroxyl number of from 50 to 250 mg KOH / g and being able to be prepared by free-radical copolymerization in an aqueous medium of (a1) hydroxyl-containing, olefinically unsaturated monomers and (a2) olefinically unsaturated monomers selected from the group consisting of (a21) monomers of the general formula (I): R<1>R<2>C=CR<3>R<4>, where at least two of the variables are substituted or unsubstituted aryl, arylalkyl or arylcycloalkyl radicals; (a22) olefinically unsaturated terpene hydrocarbons; and (a23) dimeric alpha-alkylvinylaromatics; a process for producing them and their use.

An aqueous dispersion of non-melt-processible fluoropolymer, process for making same and concentrated dispersion and powder obtained from the dispersion. The fluoropolymer particles of the dispersion have a standard specific gravity (SSG) of less than 2.225 and comprise a core of high molecular weight polytetrafluoroethylene and a shell of lower molecular weight polytetrafluoroethylene or modified polytetrafluoroethylene. At least about 1.5 weight % of the fluoropolymer particles comprise substantially rod-shaped particles having a length to diameter ratio greater than about 5.

A dispersion of non-melt-processible fluoropolymer particles having an SSG of less than about 2.225 in aqueous medium. The fluoropolymer particles comprise a core of high molecular weight polytetrafluoroethylene having an average melt creep viscosity greater than about 1.5x10<10 >Pa.s and a shell of lower molecular weight polytetrafluoroethylene or modified polytetrafluoroethylene. The shell has an average melt creep viscosity greater than about 9x10<9 >Pa.s and comprises about 5 to about 30% by weight of the particles. The fluoropolymer in the dispersion of the invention is fibrillating.

The invention discloses a lubricating-oil viscosity index improver and a preparation method thereof. The lubricating-oil viscosity index improver is obtained by performing hydrogenation modification on a polyisoprene-b-polybutadiene-b-polystyrene triblock copolymer. The preparation method comprises, adding an adjusting agent into a polymerization reaction kettle with the temperature of 60-70 DEG C and the pressure of 0.1-0.5 MPa, and then successively adding an isoprene monomer, a butadiene monomer and a styrene monomer for polymerization reaction; and obtaining the polyisoprene-b-polybutadiene-b-polystyrene triblock copolymer after the polymerization reaction is finished, and performing hydrogenation reaction on the obtained triblock copolymer, so as to obtain the lubricating-oil viscosity index improver. The preparation method is rapid and convenient in operation and simple in process, and the prepared hydrogenated polyisoprene-b-polybutadiene-b-polystyrene triblock copolymer is narrow in molecular weight distribution, complex in structure and good in chemical stability. Lubricating oil modified by the copolymer possesses the characteristics of strong thickening capability, high shearing stability, good oil-product oxidation stability and excellent low-temperature fluidity, and has wide application prospect.

The present invention provides a poly(meth)acrylate-based viscosity index improver having a core, and three or more arms comprising a polymer chain containing a structural unit represented by formula (1) and a structural unit represented by formula (2), one end of said polymer chain being bonded to the core. The weight-average molecular weight (Mw) of the poly(meth)acrylate-based viscosity index improver is at least 100,000, and the weight-average molecular weight / the number average molecular weight (Mn) is not more than 1.6. [R1 represents hydrogen or a methyl group; R2 represents the group represented by formula (3); and R3 represents an alkyl group with 1 to 18 carbons. m and n are integers that satisfy m >= 5, n >= 4, and m + n <= 31.]