6726 results about "Polyvinylidene difluoride" 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.

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 discloses a composite diaphragm which comprises a supporting layer and an organic/inorganic particle blended coating layer, laminated; the coating layer comprises a polymer particle and an inorganic particle, uniformly mixed in an adhesive; micropore structures are arranged on the surface and at the inner part of the coating layer; the porosity is 20%-80%; the aperture average is 0.01 to 10 micrometers; the polymer particle comprises one or more of polytetrafluoroethylene, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoropropylene copolymer, polyimide, polyacrylonitrile and aramid fiber resin; the particle size of the polymer particle is 0.01-10 micrometers; the inorganic particle comprises any one or more of SiO2, Al2O3, CaO, TiO2, MgO, ZnO, SnO2 and ZrO2; the particle size of the inorganic particle is 0.01-10 micrometers; the mass ratio of the polymer particle to the inorganic particle is (1:10) to (10:1). The invention further discloses a method for preparing the composite diaphragm. The composite diaphragm and the method have good thermal safety and strong in electrolyte absorption stiffness value, and meanwhile, and can achieve the advantages of low cost and low pollution.

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.

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.