3814 results about "Fluoropolymer" patented technology

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 through. 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.

In an aspect of the invention, a fluoropolymer dispersion, preferably a PTFE dispersion, is provided that comprises fluoropolymer particles having an average particle size of 10 to 400 nm dispersed in water whereby the dispersion has an amount of solids between 35 and 70% by weight. The dispersion is free of fluorinated surfactant having a molecular weight of less than 1000 g / mol (hereinafter called low molecular weight fluorinated surfactant) or contains the low molecular weight fluorinated surfactant in an amount of not more than 0.05% by weight based on the total weight solids of the dispersion. The dispersion further comprises a non-ionic non-fluorinated surfactant or mixture of non-ionic non-fluorinated surfactants and one or more non-fluorinated anionic surfactants. Through the use of a non-fluorinated anionic surfactant, a dispersion is obtained that has a low viscosity at room temperature (20° C.). The dispersion is further free of aromatic group containing non-ionic surfactants and is accordingly environmentally more friendly and can yield coatings that are less susceptible of discoloration. The amount and nature of the non-ionic non-fluorinated surfactant or mixture of non-ionic non-fluorinated surfactants is selected such that the Viscosity Transition Temperature (VTT) (measured as set forth in the examples) of the fluoropolymer dispersion is at least 26, preferably at least 28° C. In a further aspect of the invention, a method is provided to obtain the aforementioned dispersion.

A radially expandable fluid delivery device for delivering a fluid to a treatment site within the body is disclosed. 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. The fluid delivery device includes a tubular member defined by a wall having a thickness transverse to the longitudinal axis of the tubular member and extending between an inner and an outer surface. The wall is characterized by a microstructure of nodes interconnected by fibrils. The tubular member is deployable from a first, reduced diameter configuration to a second, increased diameter configuration upon the introduction of a pressurized fluid to the lumen. The tubular member includes at least one microporous portion having a porosity sufficient for the pressurized fluid to permeate through the wall. Substantially all of the nodes within the microporous portion are oriented such that spaces between the nodes form micro-channels extending from the inner surface-to the outer surface of the wall.

A novel densified fluoropolymer article is described which has a water vapor permeation of about 0.015 g-mm / m2 / day or less, and preferably has a matrix tensile strength of at least 10,000 psi in two orthogonal directions. The articles are made by compressing expanded porous PTFE at pressures, temperatures and times which result in elimination of the pores, and subsequent stretching above the crystalline melt temperature.

The present invention provides a method of removing a fluorinated surfactant from waste water comprising fluoropolymer particles. The method comprises (i) adding a non-fluorinated surfactant to the waste water (ii) contacting the thus obtained waste water with adsorbent particles to adsorb at least a portion of the fluorinated surfactant to the adsorbent particles and (iii) separating the waste water and the adsorbent particles.

A medical device provided with at least a partial surface coating of a thermoplastic copolymer of tetrafluoroethylene and perfluoroalkylvinylether that is free of cross-linking monomers and curing agents. The fluoropolymer coating is preferably an amorphous thermoplastic, is highly inert and biocompatible, has elastomeric characteristics that provide desirable mechanical properties such as good flexibility and durability. These characteristics allow the coating to be considered “functionally transparent” because it withstands mechanical deformations required for the assembly, deployment, expansion, and placement of medical devices, without any adverse effect on the mechanical and biological functionality of the coated device. Further, its inertness, derived from the perfluorocarbon structure, contributes to its functionally transparent nature. The coating can be provided with various liquid or solid additives, can be loaded with large quantities of additives including a wide range of therapeutic agents, and has excellent drug elution characteristics when elutable additives are used. The desirable mechanical characteristics are surprising given the absence of cross-linking monomers and curing agents that would otherwise render such materials inadequately biocompatible. The perfluoroalkylvinylether may be perfluoromethylvinylether, perfluoroethylvinylether or perfluoropropylvinylether.

A lens and encapsulant made of an amorphous fluoropolymer for a light-emitting diode (LED) or diode laser, such as an ultraviolet (UV) LED (UVLED). A semiconductor diode die (114) is formed by growing a diode (110) on a substrate layer (115) such as sapphire. The diode die (114) is flipped so that it emits light (160, 365) through the face (150) of the layer (115). An amorphous fluoropolymer encapsulant encapsulates the emitting face of the diode die (114), and may be shaped as a lens to form an integral encapsulant / lens. Or, a lens (230, 340) of amorphous fluoropolymer may be joined to the encapsulant (220). Additional joined or separate lenses (350) may also be used. The encapsulant / lens is transmissive to UV light as well as infrared light. Encapsulating methods are also provided.