5515 results about "Aqueous dispersion" patented technology

The invention relates to an aqueous emulsion polymerization of fluorinated monomers using perfluoropolyethers of the following formula (I) or (II). In particular, the perfluoropolyether surfactants correspond to formula (I) or (II)

CF₃—(OCF₂)_m—O—CF₂—X  (I)

wherein m has a value of 1 to 6 and X represents a carboxylic acid group or salt thereof,

CF₃—O—(CF₂)₃—(OCF(CF₃)—CF₂)_z—O-L-Y  (II)

wherein z has a value of 0, 1, 2 or 3, L represents a divalent linking group selected from —CF(CF₃)—, —CF₂— and —CF₂CF₂— and Y represents a carboxylic acid group or salt thereof. The invention further relates to an aqueous dispersion of a fluoropolymer having the aforementioned perfluoropolyether surfactant(s).

The present invention provides an aqueous emulsion polymerization of fluorinated monomers including gaseous fluorinated monomers using a perfluoro ether surfactant as an emulsifier. The perfluoro ether surfactants correspond to formula (I)

R_f—O—CF₂CF₂—X   (I)

wherein R_f represents a linear or branched perfluoroalkyl group having 1, 2, 3 or 4 carbon atoms and X represents a carboxylic acid group or salt thereof. In a further aspect, the invention also provides an aqueous fluoropolymer dispersion comprising the perfluoro ether surfactant and the use of such dispersion in the coating or impregnation of substrates.

A stable solid controlled release formulation having a coating derived from an aqueous dispersion of a hydrophobic acrylic polymer includes a substrate including an active agent selected from the group consisting of a systemically active therapeutic agent, a locally active therapeutic agent, a disinfecting and sanitizing agent, a cleansing agent, a fragrance agent and a fertilizing agent, overcoated with an aqueous dispersion of the plasticized water-insoluble acrylic polymer. The formulation provides a stable dissolution of the active agent which is unchanged after exposure to accelerated storage conditions.

A stabilized solid controlled release dosage form having a coating derived from an aqueous dispersion of ethylcellulose is obtained by overcoating a substrate including a therapeutically active with an aqueous dispersion of ethylcellulose and then curing the coated substrate at a temperature and relative humidity elevated to a suitable level above ambient conditions until the coated dosage form attains a stabilized dissolution profile substantially unaffected by exposure to storage conditions of elevated temperature and/or elevated relative humidity.

PCT No. PCT/EP97/06364 Sec. 371 Date Sep. 25, 1998 Sec. 102(e) Date Sep. 25, 1998 PCT Filed Nov. 14, 1997 PCT Pub. No. WO98/25988 PCT Pub. Date Jun. 18, 1998A blend of epoxy-amine adducts are useful as emulsifiers of aqueous epoxy resin dispersions comprises (A-1) one or more epoxy-amine adduct(s) obtained by the reaction of (i) one or more aromatic, cycloaliphatic or novolac epoxy compound(s) and (ii) one or more amine-terminated polyalkylene glycol(s) having a molecular weight of from 700-5000 and an ethyleneoxide content of at least 60% by weight in an equivalent ratio of amine-terminated polyalkylene glycol(s) to epoxy compound(s) of from 0.01:1 to 0.9:1; (A-2) one or more epoxy-amine adduct(s) derived from the reaction of (i) one or more aliphatic epoxy compound(s) and (ii) one or more amine-terminated polyalkylene glycol(s) having a molecular weight of from 700-5000 and an ethyleneoxide content of at least 60% by weight in an equivalent ratio of amine-terminated polyalkylene glycol(s) to epoxy compound(s) of from 0.01:1 to 0.9:1; (B-1) aromatic, cycloaliphatic or novolac polyglycidyl ethers; (B-2) optionally, polyglycidyl esters of aromatic or cycloaliphatic polycarboxylic acids; and (C) optionally, at least one of reactive thinners, pigments, filler or other addtitives.

Method for producing an hydrophobically associative polymer is provided which is characterized by forming a monomer solution comprising a surfactant, at least one hydrophobic ethylenically unsaturated monomer, at least one hydrophilic monomer selected from nonionic ethylenically monomers, cationic ethylenically unsaturated monomers, anionic ethylenically unsaturated monomers or mixtures thereof, and water; forming a salt solution comprising a multivalent salt and water; mixing the monomer solution and salt solution to form a mixed solution; and charging the mixed solution with an initiator, thereby polymerizing the monomers to form the hydrophobically associative polymer in a dispersion. Aqueous dispersion containing the hydrophobically associative polymer formed by the method. The aqueous dispersion containing the hydrophobically associative polymer may be used in a paint formulation, in a mobility control fluid useful in enhanced oil recovery, in a secondary or tertiary oil recovery system, in an enhanced oil recovery method, in a cementious composition, in an oil well drilling mud formulation, in a fracturing fluid formulation, in a wastewater treatment system, or in a dewatering sludge system.

Aqueous dispersions are disclosed, having a minimum film formation temperature no greater than about 50° C., that include a multi-stage emulsion polymer made by a process that includes a first polymerization stage, in which a first monomer mixture having a calculated glass transition temperature of at least about 50° C. is polymerized via free radical emulsion polymerization to obtain a first-stage emulsion polymer, and a second polymerization stage, in which a second monomer mixture, having a calculated glass transition temperature from about −30° C. to about 10° C., is polymerized via free radical emulsion polymerization, in the presence of the first-stage emulsion polymer. The dispersions are useful in a variety of coating compositions that exhibit improved block resistance.

Compositions, methods, devices and kits utilizing water-based hydrophilic coating formulations on medical implements. The composition for applying a coating comprises a sulfonated polyester, water, and a surface active agent. Methods for coating a medical implement comprise providing an aqueous dispersion comprising sulfonated polyester and surface active agent, contacting the medical implement with the aqueous dispersion, and drying the medical implement. Methods for acquiring a sample of bodily fluid from a patient comprise coating a needle with a sulfonated polyester, penetrating the needle into the patient, and drawing bodily fluid through the needle.

A liposomal aqueous dispersion and method of making the liposomal aqueous dispersion is useful for encapsulation of drugs. The liposomal aqueous dispersion comprises: an aqueous suspension medium; multilamellar liposomes comprising an anionic phospholipid and cholesterol as essential components; neutral phospholipid in a mole ratio of 0 to 40% based on the total amount of said multilamellar liposomes; and a cation moiety-containing water-soluble drug, wherein the electrolyte concentration of said aqueous suspension medium is not more than 40 mM.

Compositions are provided comprising aqueous dispersions of polythienothiophenes and colloid-forming polymeric acids. Films from invention compositions are useful as hole injection layers in organic electronic devices, including electroluminescent devices, such as, for example, organic light emitting diodes (OLED) displays, as hole extraction layers in organic optoelectronic devices, such as organic photovoltaic devices, and in combination with metal nanowires or carbon nanotubes in applications such as drain, source, or gate electrodes in thin film field effect transistors.

A polypropylene type aqueous dispersion comprising the following components (a) to (c):

wherein the component (a) has a main chain having the following features (1) and (2) and dispersion particles in the dispersion have an average particle size of at most 0.5 μm,

Feature (1) when observing a peak derived from a carbon atom of a methyl group in a propylene unit chain part comprising a head-to-tail bond by ¹³C-NMR and fixing a chemical shift of a peak top at a peak attributable to pentad expressed by mmmm to 21.8 ppm, a ratio (S₁/S) of an area S₁ of a peak of a peak top at 21.8 ppm to a total area S of peaks at from 19.8 ppm to 22.1 ppm is at least 10% and at most 60%, and when an area of a peak (mmmr) of a peak top at 21.5 to 21.6 ppm is expressed as S₂, 4+2S₁/S₂>5, and Feature (2) a content ratio (mol ratio) of propylene unit (A): other olefin unit (B) is from 100:0 to 90:10.

A process for applying two electrodeposited coatings, one on top of the other, to an electrically conductive substrate is provided. An electrically conductive first coating is applied to provide for corrosion resistance and a second polyurethane-based coating is applied to the first coating to provide chip resistance. Also, aqueous dispersions of the polyurethane coating compositions are disclosed.

The present invention provides a tetrafluoroethylene polymer aqueous dispersion obtained by carrying out a TFE polymerization in an aqueous medium in the presence of a fluorovinyl group-containing emulsifier, wherein the TFE polymer aqueous dispersion contains a particle comprising a TFE polymer dispersed in the aqueous medium, the fluorovinyl group-containing emulsifier comprises a fluorovinyl group-containing compound, and the TFE polymer aqueous dispersion has a fluorine-containing surfactant content of not higher than 1000 ppm by mass.

The invention relates to a method used for realizing large-scale preparation of monolayer oxidized graphene. The method comprises the following steps: oxidizing natural crystalline flake graphite by an oxidant to obtain oxidized graphite; after ultrasonic stripping, carrying out filtration to remove unreacted graphite and obtain the aqueous solution of oxidized graphene; and adding a flocculating agent to obtain oxidized graphene solid after settlement, filtration and drying. The method can easily separate the oxidized graphene solid from aqueous dispersion solution through flocculating settlement, thereby realizing large-scale preparation of graphene; moreover, the method has cheap and accessible raw materials, easy operation, simple process and good reproducibility, and is suitable for large-scale industrial production. The monatomic oxidized graphene prepared by the method can be used as flake reinforced phase of composite materials to prepare materials with high mechanical property and barrier property; moreover, the oxidized graphene can also be used for preparing fingerprint collecting materials, and the like. Graphene, namely the reduction product of the oxidized graphene can be used for constructing two-dimensional photoelectron components such as nano computer chips, solar battery electrodes and field effect transistors and the like.

The present invention provides a method of producing a fluoropolymer, wherein polymerization using a carboxylate ester bond-containing carboxylic acid derivative as a surfactant in an aqueous medium to give the fluoropolymer is conducted, the above carboxylate ester bond-containing carboxylic acid derivative has a carboxylate ester bond and —COOM (M representing H, NH₄, Li, Na or K), the above carboxylate ester bond may optionally be substituted by fluorine atom.

The present invention provides a surfactant making it possible to obtain particles comprising a fluoropolymer at a size smaller in diameter in an aqueous dispersion obtained by polymerization in the presence of the same. The present invention is a surfactant comprising a fluorine-containing-sulfobutanedioic-acid-ester derivative represented by the general formula (i):

Y—Rf¹—(CH₂)_m—OCOCH(SO₃M)-CH₂COO—(CH₂)_n—Rf²—Y  (i)

wherein Y represents hydrogen atom or fluorine atom; when Y is hydrogen atom, one of Rf¹ and Rf² is —(CF₂CF₂)₃— and the other is —(CF₂CF₂)₂— or —(CF₂CF₂)₃— and, when Y is fluorine atom, Rf¹ and Rf² are the same or different and each is a divalent hydrocarbon group containing 1 to 4 carbon atoms and containing at least one fluorine atom; m and n are the same or different and each represents an integer of 1 to 3; and M represents NH₄, Li, Na, K or H.

The invention relates to a preparation method for the hydroxyl acrylic aqueous dispersion of high performance and two-component waterborne polyurethane, which comprises four steps: synthesizing hydroxyl acrylic resin, removing a solvent, a neutralization salt forming reaction and deionization and aqueous dispersion. The hydroxyl acrylic aqueous dispersion prepared by the invention has proper molecular weight and the molecular weight is distributed much narrower, thus being beneficial for forming a uniform coating, reducing the plasticizing effect of small molecule substance to the coating, and increasing the comprehensive performance of the coating. The dispersion can be combined with an isocyanate curing agent to be used as wood coatings, corrosion protective coatings, industrial maintenance coatings, floor coatings and the like, and also can be used for preparing a two-component waterborne polyurethane adhesive, etc.

A coating containing pigment particles and a polymer matrix is provided. The coating contains pigment particles that have a scattering coefficient with a linear or quasi-linear relationship to the pigment volume concentration of those pigment particles. The coating has improved hiding and is useful as a protective coating or an aesthetic coating on an underlying substrate. Also provided are compositions useful for preparing the coating, including covalently bonded composite particles and aqueous dispersions containing composite particles. The composite particles each contain a pigment particle with a plurality of polymer particles attached by adsorption on the outer surface of the pigment particle or by covalent bonding to the pigment particle through a coupling agent. Methods to prepare the composite particles and coating compositions containing the composite particles are also provided.

Compositions are provided comprising aqueous dispersions of electrically conducting organic polymers and a plurality of nanoparticles wherein pH can be adjusted for improved organic electronic device performance. Films deposited from invention compositions are useful as buffer layers in electroluminescent devices, such as organic light emitting diodes (OLEDs) and electrodes for thin film field effect transistors. Buffer layers containing nanoparticles may have a much lower conductivity than buffer layers without nanoparticles. In addition, when incorporated into an electroluminescent (EL) device, buffer layers according to the invention contribute to higher stress life of the EL device.