3046 results about "Polyvinylidene fluoride" patented technology

Devices, systems and methods are provided for stimulation of tissues and structures within a body of a patient. In particular, implantable leads are provided which are comprised of a flexible circuit. Typically, the flexible circuit includes an array of conductors bonded to a thin dielectric film. Example dielectric films include polyimide, polyvinylidene fluoride (PVDF) or other biocompatible materials to name a few. Such leads are particularly suitable for stimulation of the spinal anatomy, more particularly suitable for stimulation of specific nerve anatomies, such as the dorsal root (optionally including the dorsal root ganglion).

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.

To provide a process for producing a lithium ion secondary battery which can have any arbitrary shape, such as thin shape, and yet exhibits high performance. In a method of fabricating a battery comprising a positive electrode 1, a negative electrode 4, and a separator 7, a binder resin solution mainly comprising polyvinylidene fluoride is applied to the separator 7, and the positive electrode 1 and the negative electrode 4 are laid thereon, followed by drying to form a battery laminate, which is then impregnated with an electrolytic solution.

The invention discloses a preparation method of a ceramic-gel polymer multilayer composite lithium battery diaphragm. The preparation method comprises the following steps: 1, preparing aqueous PVDF (polyvinylidene fluoride) slurry and aqueous ceramic slurry; 2, thermally compounding a polypropylene diaphragm and a polyethylene diaphragm at 50-100 DEG C to obtain PP/ PE (polypropylene/ polyethylene) composite diaphragm; 3, with the PP/ PE composite diaphragm obtained in the step 2 as a coating substrate, coating the aqueous slurry prepared in the step 1 onto the PE surface of the substrate: coating the aqueous ceramic slurry to form a ceramic layer first and then coating the aqueous PVDF slurry to form a gel polymer layer, with the coating speed of 5-100m/min, and drying in a drying box with the temperature of 30-100 DEG C to obtain a final four-layer composite diaphragm. The invention further discloses a ceramic-gel polymer multilayer composite lithium battery diaphragm prepared by the preparation method. The prepared ceramic-gel polymer multilayer composite lithium battery diaphragm has the advantages of high thermal safety and high capability of keeping electrolyte.

The invention discloses a large-capacity high-power polymer lithium iron phosphate power battery. The weight ratio of anode slurry is as follows: 81 to 85 percent of lithium iron phosphate, 1 to 5.5 percent of superconduction carbon, 0 to 2.5 percent of conductive carbon soot, 0 to 4 percent of conductive black lead, 0 to 2.5 percent of crystalline flake graphite, 0 to 2 percent of carbon nanometer tube as well as 6 to 7.5 percent of polyvinylidene fluoride; the weight ratio of cathode slurry is as follows: 89 to 91 percent of cathode material, 1 to 3.5 percent of superconduction carbon, 0 to 2 percent of conductive carbon soot, 0 to 4 percent of conductive black lead, 2.5 to 3.5 percent of styrene-butadiene rubber as well as 1.5 to 2 percent of sodium carboxymethyl cellulose; the steps for preparing the battery are as follows: preparing slurry, coating the anode and the cathode, rolling and pressing a polar plate, transversely and separately cutting the polar plate, baking the polar plate, welding the polar ears of the anode and the cathode, preparing a battery cell, putting the electric core into a shell and sealing, baking the electric core, injecting liquid into the battery as well as forming the battery and dividing the volume of the battery. The invention relates to a lithium-ion secondary battery which can provide drive energies for electric tools, electric bicycles, motor cars and electric vehicles.

A porous polymeric membrane formed from a blend of a polymeric membrane forming material, such as polyvinylidene fluoride or polysulfone and a polymeric reactivity modifying agent adapted to modify the surface active properties of the porous polymeric membrane. The reactivity modifying agent is preferably a linear polymeric anhydride, such as poly(alkyl vinyl ether/maleic anhydride). The surface activity modifications include modification of the hydrophilicity/hydrophobicity balance of the membrane, or hydrolysis followed by reaction with a polyamine to form a crosslinked polyamide layer. Such modified membranes have use as reverse osmosis membranes.

Representative embodiments provide a composition for printing a liquid or gel separator utilized to separate and space apart first and second conductors or electrodes of an energy storage device, such as a battery or a supercapacitor. A representative composition comprises a plurality of particles, typically having a size (in any dimension) between about 0.5 to about 50 microns; a first, ionic liquid electrolyte; and a polymer or polymeric precursor. In another representative embodiment, the plurality of particles comprise diatoms, diatomaceous frustules, and/or diatomaceous fragments or remains. Another representative embodiment further comprises a second electrolyte different from the first electrolyte; the plurality of particles are comprised of silicate glass; the first and second electrolytes comprise zinc tetrafluoroborate salt in 1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid; and the polymer comprises polyvinyl alcohol (“PVA”) or polyvinylidene fluoride (“PVFD”). Additional components, such as additional electrolytes and solvents, may also be included.

A weather resistant coating composition comprising a miscible polymer blend of highly crystalline polyvinylidene fluoride polymer and polyalkyl methacrylate, such as PVDF and PMMA. The miscible blend comprises from about 50 weight percent to about 90 weight percent polymer comprising polyvinylidene fluoride and from about 10 weight percent to about 50 weight percent polyalkyl methacrylate. The polyalkyl methacrylate having a molecular weight within the range of about 25,000 grams per mole to about 200,000 grams per mole. The crystallinity of the polyvinylidene fluoride polymer is about 20% to about 70%. The weather resistant coating has excellent and unexpected physical characteristics, including solvent resistance and gloss retention.

Disclosed are mask optics configured to be implanted in a cornea of a patient. In one embodiment, the body of the optic has a light transmitting portion, a light blocking portion disposed about the light transmitting portion, and an outer periphery surrounding the light blocking portion. The optic is adapted to reside between two intracorneal layers of a cornea. The mask optic may be formed from a material comprising a highly fluorinated polymeric material and an opacification agent. Preferred highly fluorinated polymeric materials include polyvinylidene fluoride (PVDF) and preferred opacification agents include carbon. The highly fluorinated polymeric material is preferably resistant to degradation upon exposure to ultraviolet light.

A porous polymeric membrane formed from a blend of a polymeric membrane forming material, such as polyvinylidene fluoride or polysulfone and a polymeric reactivity modifying agent adapted to modify the surface active properties of the porous polymeric membrane. The reactivity modifying agent is preferably a linear polymeric anhydride, such as poly(alkyl vinyl ether/maleic anhydride). The surface activity modifications include modification of the hydrophilicity/hydrophobicity balance of the membrane, or hydrolysis followed by reaction with a polyamine to form a crosslinked polyamide layer. Such modified membranes have use as reverse osmosis membranes.

The invention relates to a method for preparing a high-flux composite membrane from a dopamine-modified nanometer material and belongs to the technical field of modification of membrane materials. The method is characterized by comprising the following steps of: forming an active poly-dopamine composite layer on the surfaces of titanium dioxide nanometer grains by utilizing automatic polymerization of dopamine, selecting different concentrations of dopamine-modified titanium dioxide grains, and adding the modified nanometer grains utilized as additives into a membrane casting solution, in which the mass fraction of PVDF (Polyvinylidene Fluoride) is 13% and the mass fraction of PVP (Polyvinyl Pyrrolidone) is 4%, so as to bend and modify according to different proportions, thus obtaining a composite membrane prepared from dopamine-modified nanometer titanium dioxide. The method for preparing the high-flux composite membrane from the dopamine-modified nanometer material, disclosed by the invention, has the advantages that dopamine-modified titanium dioxide can be greatly dispersed in an organic solvent to form a uniform dispersed phase; the additive can be used for effectively improving the hydrophilcity and anti-pollution capability of the high-flux composite membrane; and the dopamine modification method is simple, the condition is gentle, the flux of the prepared membrane is large and the anti-pollution capability is strong.

The invention relates to a terpolymer of tetrafluoroethylene (TFE) monomer, polyvinylidene fluoride (PVDF) monomer and hexafluoropropylene (HFP) monomer for forming an ultrafiltration or microfiltration membrane, method of forming said membranes, and to the ultrafiltration or microfiltration membranes themselves. The invention also relates to a method of forming a polymeric ultrafiltration or microfiltration membrane including preparing a leachant resistant membrane dope which incorporates a leachable pore forming agent, casting a membrane from the dope and leaching the pore forming agent from the membrane. The invention also relates to a method of preparing a polymeric ultrafiltration or microfiltration membrane of improved structure including the step of adding a nucleating agent to the membrane dope before casting.

The invention relates to an anode for lithium secondary battery comprising vapor grown carbon fiber uniformly dispersed without forming an agglomerate of 10 μm or larger in an anode active material using natural graphite or artificial graphite, which anode is excellent in long cycle life and large current characteristics. Composition used for production for the anode can be produced, for example, by mixing a thickening agent solution containing an anode active material, a thickening agent aqueous solution and styrene butadiene rubber as binder with a composition containing carbon fiber dispersed in a thickening agent with a predetermined viscosity or by mixing an anode active material with vapor grown carbon fiber in dry state and then adding polyvinylidene difluoride thereto.

A metal-air battery includes a housing having an aperture for the passage of air and a pair of electrodes that extend from the housing. An air cathode may be interconnected with one of the electrodes and an anode may include a metal foil that is interconnected with another of the electrodes. A separator may be interposed between the air cathode and the metal foil and a barrier layer may surround the metal foil. The barrier layer may function to substantially reduce the passage of moisture to the metal foil. A method of making a metal-air battery is also presented.

The invention discloses a plate-tubular porous membrane based on polyvinylidene fluoride mixture, and relative production. The membrane substantially comprises polyvinylidene fluoride, dual-block amphipathic epoxyethane, and inorganic particles. And the preparation comprises that mixing polyvinylidene fluoride, dual-block amphipathic epoxyethane, inorganic particles, aperture adjusting agent and polarity solvent to obtain the membrane preparing liquid, using said membrane preparing liquid into plate or tubular liquid membrane, immerging the liquid membrane into solidifying bath mainly comprising water to be solidified into plate or tubular membrane. And the apertures of plate membrane and tubular membrane are 0.01-5.0 and 0.01-0.2 micrometers. The hydrophilic chain section of amphipathic epoxyethane is abundant at the face or aperture walls of the membrane, while said two membranes are both better in hydrophilic property and permeable property, with significant resistance on organic adsorption, to be used as ultra-filter membrane and micro-filter membrane in membrane water treatment.

The invention discloses a hydrophilic polyvinylidene fluoride hollow fiber microporous membrane and the preparation method thereof. The main composition and the mass content of the membrane are 70% to 90% of polyvinylidene fluoride, amphiphilic poly-(propylene oxide-oxirane), 5% to 29% of poly-(methacrylic acid- acrylic acid) or poly-(methacrylic acid methyl ester-vinyl alcohol) copolymer and 1% to 5% of nano-silicon dioxide. The membrane preparation method is that all the components are mixed and dissolved with aperture regulator, thickener and solvent to obtain the membrane preparation liquid; after that, the hollow fiber forming is carried out through a dry-wet spinning technique, and finally cleaning and drying are implemented. The obtained membrane has adjustable internal diameter and external diameter, 60% to 80% of porosity and the aperture ranging from 0.01micron to 0.2micron. As a water disposal separating membrane material with excellent performance, the invention has the advantages of being able to be fully humid, organic adsorption resistance and great water flux, etc.

A laser catheter with a pressure sensor is provided according to embodiments of the invention. The pressure sensor may be coupled with the distal end of the laser catheter and may comprise any of various piezoelectric materials, for example Polyvinylidene Difluoride (PVDF). In various embodiments of the invention the pressure sensor is configured to detect pressure longitudinally and coaxially. The pressure sensor may provide an electric potential that is proportional to the vessel pressure and may be used to monitor and/or adjust laser parameters. In other embodiments the results from the pressure sensor may be used to determine the vessel size and/or the type of material being ablated.

The invention relates to a carbon-sulfur composite material used for a positive pole of a lithium-sulfur battery. The carbon-sulfur composite material is characterized in that elemental sulfur is filled in a multi-hole hollow carbon ball which is synthesized through a simple template method, and the elemental sulfur is injected into the multi-hole hollow carbon ball by adopting a fusion diffused method; the carbon-sulfur composite material is used for preparing a positive pole material of a high-performance lithium-sulfur battery cell, the positive pole is composed of the carbon-sulfur composite material, a binding agent and an electric conduction agent, and polytetrafluoroethylene or polyvinylidene fluoride is used as the binding agent; and the electric conduction agent is a mixture of one or more than two of carbon nanometer fibre, electric conduction graphite, acetylene black and Super p in any proportion. The carbon-sulfur composite material provided by the invention has the advantages that compared with the reportorial lithium-sulfur secondary battery, the preparation method of the anode material is simple, the large specific capacity is 1450 Ahg-1, the coulomb efficiency is high and is greater than 99.0%, the cycle performance is good, the initial capacity is kept 93.6% after circulating for 50 weeks and the like, and the carbon-sulfur composite material is expected to be applied to the next generation large-scale stored energy batteries.

The invention relates to a method for preparing hydrophilic PVDF microporous barrier. The principal raw material is polyvinylidene fluoride with the range of molecular weight: 5000 to 50000. It prepares hydrophilic PVDF microporous barrier by the method of separating solution and compounding dip-coating modification. It especially suits the occasion of effluent treatment, medicine separation and biochemy. The technology can prepare microporous barriers with plate type and hollow fiber type.

The invention provides a polyvinylidene fluoride microporous film and a preparation method; the polyvinylidene fluoride microporous film is prepared by using polyvinylidene fluoride, fatty alcohol (non solvent) and polar organic solvent as raw materials, the proportioning of which is as follows: the mass content of polyvinylidene fluoride is 10%-15%, and the content of non solvent is 6-12%; the specific steps are as follows: polyvinylidene fluoride, polar organic solvent and non solvent are mixed, dissolved and filtered, set aside and are deaerated to obtain clear casting film liquid which is struck on a coarse structure template substrate and placed in air; gel forms film in a coagulating bath, is processed by hot water, and then soaked in water and absolute ethyl alcohol to obtain high hydrophobic polyvinylidene fluoride microporous film; the contact angle between the surface of high hydrophobic polyvinylidene fluoride microporous film and water reaches 130 degrees to 140 degrees, air flux of the film reaches 6.0m<3>/(m<2>-h-kPa) under 60kPa, the maximum bore diameter is less than 0.5 mum, tensile strength reaches breaking strength which is larger than 5Mpa, and the elongation at break is larger than 50%. The invention is the polyvinylidene fluoride microporous film with high hydrophobicity, high flux and good mechanical strength and the preparation method, which is mainly applied to the film distillation and associated film process.

An acoustic sensor having one or more segments are electrically coupled to provide a response corresponding to an acoustic pressure applied to the segments. Each segment contains at least one substrate of a desired shape and at least two active members made from a flexible, resilient piezoelectric material, preferably, a polyvinylidene fluoride material. Each substrate includes an enclosed chamber on an outer surface wherein a first active element is within the chamber and a second active element is sealingly placed on the enclosed chamber. The second active element is preferably bonded to a compliant diaphragm sealed to the substrate to provide the sealed chamber. An output response from the first active member is combined with an output response from the second active member to provide for a combined output response having reduced noise. The second active element is covered with a protective layer of a suitable material, preferably a polymer material.

The invention discloses a method of producing the hyperfiltration membrane of amphiphilic copolymer modified polyvinylidene fluoride, comprising the following steps: 1) mixing polyvinylidene fluoride, poly (methyl methacrylate - monomethyl ether polyoxyethylene methyl methacrylate), additives, non-solvent and solvent to form the casting film solution; 2) making the casting film solution into the polyvinylidene fluoride membrane by using the film forming machine and then soaking in the coagulation bath; 3) conducting the posttreatment of hydrophilicity; 4)obtaining the hydrophilic polyvinylidene fluoride ultrafiltration membrane after cleaning and drying. The method is characterized in that the brush shape, chain ball shape or dumbbell shape amphiphilic copolymer are mixed with the polyvinylidene fluoride to produce the polyvinylidene fluoride hyperfiltration membrane with hydrophilicity, anti-pollution, large flux and high retention rate by adopting the solution phase conversion method. The method has the advantages that the obtained membrane is provided with dozens to hundreds nanometer of particular densified hydrogel surface layers, the contact angle of the membrane surface can be reduced below 60 degrees and can be lowered to 0 degree within tens of seconds, the water flux can reach 1000L /m<2>/ h (0.1Mpa) or above, the retention rate of BSA can reach 90% or more and the recovery rate of water cleaning flux can reach 90% or higher.

The invention relates to a foamed fluoropolymer, preferably a polyvinylidene fluoride (PVDF) structure, such as from Kynar® resins. The foamed structure is continuous self-supporting, sized, and has a dense skin. The foamed structure is manufactured in a process using foaming agents and nucleating agents. The structure is sized into a specific shape during the manufacturing process—requiring a good melt viscosity of the PVDF foam. In one process, a master batch containing the nucleating agent is used. The foamed article could be a sheet, film, profile, tube, pipe, article, rod foam-core structure, or other self-supporting shape. Foamed tubes, pipes, rods, sheets and conduit are especially useful. The foamed structure of the invention provides added value by being lighter weight, more flexible, and more impact resistant than a comparable non-foamed PVDF structure. It also has increased hysteresis, increased insulation properties, reduced dielectric constant, and increased compressibility.

The invention relates to a back panel of a solar cell and a preparation method thereof. The solar back panel is provided with three polymer film layers from top to bottom, namely an adhesive weatherable layer, an adhesive reinforcing layer and an adhesive moisture-retarding layer, wherein the adhesive weatherable layer is a PVDF(polyvinylidene fluoride)/EVA (ethylene vinyl acetate) alloy layer, the adhesive reinforcing layer is a PET (polyethylene terephthalate)/PMMA (polymethyl methacrylate) alloy layer, and the adhesive moisture-retarding layer is a PVDF/PVB (polyvinyl butyral) alloy layer. In the preparation method, a multi-layer melting and co-extrusion method is adopted for realizing interface-free fusion of the three film layers, and a composite film can achieve good dimensional stability by online high-temperature shaping. The structure of the back panel of the solar cell only comprises the three layers, an adhesive layer does not need to be used, the preparation process is simple, the steps of sizing and hot-pressing are omitted, and the production efficiency is high; and simultaneously, the back panel has excellent performances and is in line with the packaging requirements of the solar cell.

The invention relates to a solar battery backboard which takes a modified polyvinylidene fluoride alloy layer as a weathering protective layer. The backboard comprises the following components according to the adhesion in turn: a weathering layer, an adhesive layer, a structure-enhancing layer, a second adhesive layer and a second weathering layer; wherein, the first weathering layer and the second weathering layer are the polyvinylidene fluoride alloy layers modified by inorganic materials; preferably, the polyvinylidene fluoride alloy layer is a plastic alloy layer formed by the polyvinylidene fluoride and the inorganic materials with the thickness of 4-40 mum; the structure-enhancing layer is a polyethylene qlycol terephthalate layer; the first adhesive layer and the second adhesive layer can be one of the following three, namely, a polyurethane adhesive layer, an acrylic ester adhesive layer or an epoxy adhesive layer with the thickness of 1mum-30mum. The invention features novel structure, easily obtained materials, greatly reduced cost and fine performance, conforms to the requirement of backboard, and has important significance on solar energy industry.

The high-dielectric constant composite material contains carbon nanotube 2-12 vol%, BaTiO3 20 vol% and organic polyvinylidene fluoride 68-78 vol%. The preparation process is one hot pressing process with low forming temperature and short period. The composite material has high dielectric constant over 450, simple preparation process and high toughness. Through regulating the content of additive components and different physical and chemical treatment, the dielectric constant and toughness may be altered obviously. It has wide application foreground.

A preparation of composite hollow fiber membrane adopts solution phase transfer hollow fiber spinning process, makes poly(ethylene terephthalate) or polysulfone, solvent and pore-forming agent into a base membrane spinning solution of composite hollow fiber membrane, makes polyvinylidene fluoride or other copolymers or mixture of same, solvent and pore-forming agent into composite layer spinning solution of composite hollow fiber membrane and simultaneously extrudes the said two spinning solution and core solution in the hole of the spinneret central pipe through the spinneret for outside condensation bath. The solvents and pore-forming agents in the two kinds of spinning solutions prepared in said step (1) and (2) enters condensation solution phase and the polymers, as the composite layer and the base membrane materials, precipitates into polymer hollow fiber membrane due to phase transfer, producing high-strength and high-flux hydrophilic composite hollow fiber membrane.

This invention relates to an improved polyvinylidene fluoride-based composition useful for forming a flexible, tack-free, nonflammable, substantially fluid resistant barrier film with substantially improved durability and skin-adhesion properties. The composition providing a long-lasting protective barrier film capable of disinfecting the skin surface of normally present microorganisms upon initial application, and said film imparting continuous and prolonged antimicrobial properties to the skin surface through sustained release of an encapsulated antimicrobial agent. The barrier film is further capable of remaining substantially adherent to the skin surface after prolonged exposure to biological fluids. A kit and methods of use for the composition are disclosed.

The invention discloses a method for preparing polyvinylidene fluoride ultra-filtration membranes. The method includes the steps of mixing the polyvinylidene fluoride with diluents, and heating the mixture to form a homogeneous phase solution, wherein the diluents are a mixture of a solvent and a non-solvent of the polyvinylidene fluoride, and at least one of the solvent and the non-solvent of the polyvinylidene fluoride can be dissolved in water; subjecting the homogeneous phase solution to knife coating on a supporting screen to form a plate-shaped membrane casting solution or to be spinned into a membrane casting solution in a hollow fiber shape by a spinneret, submerging the membrane casting solution into a cooling liquid to be cooled, subjecting the membrane casting solution to phase separation and solidifying into membranes; extracting the diluents in the membranes through an extracting agent to obtain the polyvinylidene fluoride membranes. Sections of the polyvinylidene fluoride membranes are in a homogeneous spongeous structure with bore diameters in a range of 0.02 to 4 microns, and the membranes have surface layers with surface bore diameters ranging from 2 nanometers to 100 nanometers. Simultaneously, the polyvinylidene fluoride ultra-filtration membranes have the advantages of high strength, porosity, flux and separation accuracy.

In a method for producing hollow fiber membranes which comprises melt kneading a mixture comprising polyvinylidene fluoride and an organic liquid or a mixture comprising polyvinylidene fluoride, an organic liquid and an inorganic fine powder, extruding the kneaded mixture to form hollow fibers, and extracting the organic liquid or the organic liquid and the inorganic fine powder from the hollow fibers, which includes the steps of drawing the hollow fibers before or after termination of the extraction and then shrinking the fibers. According to this method, it is possible to stably produce hollow fiber membranes having dense pores and having a high water permeation performance, excellent endurance and stain resistance, and which are suitable for filtration uses such as removal of turbidity of water.