3699 results about "Fluoropolymer" 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 invention provides a fluorinated surfactant having the general formula:

[R_f—(O)_t—CHF—(CF₂)_n—COO—]_iXⁱ⁺  (I)

wherein R_f represents a partially or fully fluorinated aliphatic group optionally interrupted with one or more oxygen atoms, t is 0 or 1 and n is 0 or 1, Xⁱ⁺ represents a cation having a valence i and i is 1, 2 or 3. The surfactant can be used in emulsion polymerization of fluoromonomers to prepare fluoropolymers.

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 medical balloon catheter assembly includes a balloon having a permeable region and a non-permeable region. The balloon is constructed at least in part from a fluid permeable tube such that the permeable region is formed from a porous material which allows a volume of pressurized fluid to pass from within a chamber formed by the balloon and into the permeable region sufficiently such that the fluid may be ablatively coupled to tissue engaged by the permeable region. The non-permeable region is adapted to substantially block the pressurized fluid from passing from within the chamber and outwardly from the balloon. The porous material may be a porous fluoropolymer, such as porous polytetrafluoroethylene, and the pores may be created by voids that are inherently formed between an interlocking node-fibril network that makes up the fluoropolymer. Such voids may be created according to one mode by expanding the fluoropolymer. The balloon may be formed such that the porous material extends along both the permeable and non-permeable regions. In one mode of this construction, the porous material is porous along the permeable region but is non-porous along the non-permeable region, such as for example by expanding only the permeable region in order to render sufficient voids in the node-fibril network to provide permeable pores in that section. The voids or pores in the porous material may also be provided along both permeable and non-permeable sections but are substantially blocked with an insulator material along the non-permeable section in order to prevent fluid from passing therethrough. The insulator material may be dip coated, deposited, or extruded with the porous material in order to fill the voids. The insulator material may in one mode be provided along the entire working length of the balloon and then selectively removed along the permeable section, or may be selectively exposed to only the non-permeable sections in order to fill the voids or pores there.

This invention relates to flexible, transparent and conductive coatings and films formed using carbon nanotubes (CNT) and, in particular, single wall carbon nanotubes, with polymer binders. Preferably, coatings and films are formed from carbon nanotubes applied to transparent substrates forming one or multiple conductive layers at nanometer level of thickness. Polymer binders are applied to the CNT network coating having an open structure to provide protection through infiltration. This provides for enhancement of properties such as moisture resistance, thermal resistance, abrasion resistance and interfacial adhesion. Polymers may be thermoplastics or thermosets, or a combination thereof. Polymers may also be insulative or inherently electrical conductive, or any combination of both. Polymers may comprise single or multiple layers as a basecoat underneath a CNT coating, or a topcoat above a CNT coating, or combination of the basecoat and the topcoat forming a sandwich structure. A fluoropolymer containing binder, which is a solution of one fluoropolymer or a blend of fluoropolymers, which may be formulated with additives, is applied onto a carbon nanotube-based transparent conductive coating at nanometer level of thickness on a clear substrate such as PET and glass. The fluoropolymers or blend can be either semi-crystalline (with low level of crystallinity) or amorphous, preferably to be amorphous with low refraction index. Binder coating thickness can be adjusted by changing binder concentration, coating speed and/or other process conditions. This binder coating significantly improves optical transparency, and also maintain or increases conductivity of the CNT-based coating. With other benefits such as abrasion, thermal and moisture resistance, this binder coating and the resulting products is used for display and electronic applications.

The following resist composition which is excellent particularly in transparency to light beams and dry etching properties and gives a resist pattern excellent in sensitivity, resolution, evenness, heat resistance, etc., as a chemical amplification type resist, is presented. A resist composition which comprises a fluoropolymer (A) having repeating units represented by a structure formed by the cyclopolymerization of one molecule of a fluorinated diene and one molecule of a monoene, in which the monoene unit in each repeating unit has a blocked acid group capable of regenerating the acid group by the action of an acid, an acid-generating compound (B) which generates an acid upon irradiation with light, and an organic solvent (C).

A polymer composition is disclosed, which comprises a matrix polymer, a fluoropolymer that may be at least partially encapsulated by an encapsulating polymer, and a filler. Methods for making the polymer compositions and articles made of such compositions are also disclosed. The compositions and article can have improved tensile modulus, ductility, and/or impact properties.

The present invention provides a fluorinated surfactant having the general formula:

[R_f—(O)_t—CQH—CF₂—O]_n—R-G  (I)

wherein R_f represents a partially or fully fluorinated aliphatic group optionally interrupted with one or more oxygen atoms, Q is CF₃ or F, R is an aliphatic or aromatic hydrocarbon group, G represents a carboxylic or sulphonic acid or salt thereof, t is 0 or 1 and n is 1, 2 or 3. The surfactant is particularly useful in polymerizing fluorinated monomers in an aqueous emulsion polymerization.

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 1.5×10¹⁰ Pa·s and a shell of lower molecular weight polytetrafluoroethylene or modified polytetrafluoroethylene. The shell has an average melt creep viscosity greater than about 9×10⁹ Pa·s and comprises about 5 to about 30% by weight of the particles. The fluoropolymer in the dispersion of the invention is fibrillating.

A fluoropolymer coated film comprising polymeric substrate film and fluoropolymer coating on the polymeric substrate film. The fluoropolymer coating comprises fluoropolymer selected from homopolymers and copolymers of vinyl fluoride and homopolymers and copolymers of vinylidene fluoride polymer blended with compatible adhesive polymer comprising functional groups selected from carboxylic acid, sulfonic acid, aziridine, anhydride, amine, isocyanate, melamine, epoxy, hydroxy, anhydride and mixtures thereof. The polymeric substrate film comprises functional groups on its surface that interact with the compatible adhesive polymer to promote bonding of the fluoropolymer coating to the substrate film.

Acrylic Modified Fluoropolymers based on vinylidene fluoride polymers are disclosed wherein the acrylic phase is capable of entering into crosslinking reactions. The final cured products provide superior solvent extractability resistance to the fluoropolymer phase.

The invention relates to an aqueous fluoropolymer, and preferably polyvinylidene fluoride (PVDF), composition for manufacturing electrodes for use in non-aqueous-type electrochemical devices, such as batteries and electric double layer capacitors. The composition contains aqueous PVDF binder, and one or more powdery electrode-forming materials. In one embodiment, the composition is free of fluorinated surfactant In another embodiment, one or more fugitive adhesion promoters are added. The electrode formed from the composition of the invention exhibits interconnectivity and irreversibility that is achieved from the use of aqueous PVDF binder.

A method of making a radially expandable fluid delivery device includes providing a tube of biocompatible fluoropolymer material with a predetermined porosity based on an extrusion and expansion forming process, applying a radial expansion force to the tube expanding the tube to a predetermined diameter dimension, and removing the radial expansion force. The tube is radially inelastic while sufficiently pliable to be collapsible and inflatable from a collapsed configuration to an expanded configuration upon introduction of an inflation force, such that the expanded configuration occurs upon inflation to the predetermined diameter dimension. The fluid delivery device is constructed of a microporous, biocompatible fluoropolymer material having a microstructure that can provide a controlled, uniform, low-velocity fluid distribution through the walls of the fluid delivery device to effectively deliver fluid to the treatment site without damaging tissue proximate the walls of the device.

An economic, optically transmissive, stain and ink repellent, durable low refractive index fluoropolymer composition for use in an antireflection film or coupled to an optical display. In one aspect of the invention, the composition is formed from the reaction product of a fluoropolymer, a C═C double bond group containing silane ester agent, and an optional multi-olefinic crosslinker. In another aspect of the invention, the composition further includes surface modified inorganic nanoparticles. In another aspect, the multi-olefinic crosslinker is an alkoxysilyl-containing multi-olefinic crosslinker.

A placement guide apparatus with an improved hydration inducing plug used in coupling a noninvasive analyzer to a sampling site to determine analyte in the human body is disclosed. The hydration inducing plug includes at least one fluoropolymer that may be used as a coupling agent. The guide apparatus may further include an automated or semi-automated coupling fluid delivery system. Use of either of these couplers mitigates issues associated with related technology and enhances noninvasive analyte measurements, such as a near-IR diffuse reflectance based noninvasive glucose concentration analyzer.

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 present invention provides a fluoropolymer dispersion comprising fluoropolymer particles having an average particle size of 10 to 400 nm dispersed in water whereby the dispersion is free of fluorinated surfactant having a molecular weight of less than 1000 g/mol or contains the fluorinated surfactant having a molecular weight of less than 1000 g/mol in an amount of not more than 0.025% by weight based on the total weight of solids in the dispersion. The dispersion further comprises a non-ionic surfactant and an anionic surfactant selected from fluorinated anionic surfactants having a molecular weight of at least 1000 g/mol, non-fluorinated anionic surfactants and mixtures thereof.

Fluoropolymers are prepared by a process comprising polymerizing at least one fluoromonomer in an aqueous reaction medium containing monomer, a radical initiator and a 3-allyloxy-2-hydroxy-1-propanesulfonic acid salt as surfactant. The medium may optionally contain one or more of an antifoulant, a buffering agent and a chain-transfer agent.

The present invention is an implantable cable and a process to manufacture said implantable cable. The cable is composed of a biocompatible fluoropolymer, in which biocompatible conductor wires are embedded. The entire cable is heat treated at various stages to ensure the wires are securely embedded. The cable is then undulated to enhance its pliability and flexibility. Further treatment activates the outer surface of the cable, following which it may be encapsulated in silicone.