7761 results about "Polytetrafluoroethylene" patented technology

A surgical implant is provided that includes first and second abutment surfaces between which are positioned a force imparting mechanism. A sheath is positioned between the first and second abutment surfaces, and surrounds the force imparting mechanism. The sheath is fabricated from a material that accommodates relative movement of the abutment members, while exhibiting substantially inert behavior relative to surrounding anatomical structures. The sheath is generally fabricated from expanded polytetrafluoroethylene, ultra-high molecular weight polyethylene, a copolymer of polycarbonate and a urethane, or a blend of a polycarbonate and a urethane. The force imparting member may include one or more springs, e.g., a pair of nested springs. The surgical implant may be a dynamic spine stabilizing member that is advantageously incorporated into a spine stabilization system to offer clinically efficacious results.

An encapsulated stent having a stent or structural support layer sandwiched between two biocompatible flexible layers. One preferred embodiment has a stent cover which includes a tubular shaped stent that is concentrically retained between two tubular shaped grafts comprised of expanded polytetrafluoroethylene. Another preferred embodiment has a stent graft which includes at least one stent sandwiched between the ends of two tubular shaped grafts wherein at least a portion of the grafts are unsupported by the stent. Still another embodiment includes an articulating stented graft which includes a plurality of stents spaced apart from one another at a predetermined distance wherein each stent is contained between two elongated biocompatible tubular members. The graft/stent/graft assemblies all have inseparable layers.

A polymeric, surgical clip having first and second curved leg members joined at their proximal end by a hinge portion and movable from an open position to a closed position for clamping a vessel between curved opposing inner surfaces. The clip includes a coating on its exterior which reduces the friction between the leg members and complementary locking mechanisms disposed at the distal end portions of the leg members, and stabilizes closing of the clip. The coating can be any coating, including a polymer coating such as one which includes polytetrafluoroethylene. The coating may be applied using a solvent such as HFC43-10.

A lubrication system is disclosed which minimizes friction and that is useful for application on the surface of a flexible portion of a medical device. Such a lubrication system includes a lubricant that is able to move when the flexible portion of the medical device flexes and is biocompatible and is not degraded by the application of alcohol or other conventional medical sterilizing and cleaning agents. The lubricant is bonded to the surface of the flexible portion of the medical device. The lubrication system may be used on an elastomeric septum, such as a silicone rubber elastomer. The lubricant coating may be any type of coating that can be chemically bonded to the elastomer, such as di-paraxylene, poly-(p-xylene), polytetrafluoroethylene, or polyvinylpyrrolidone.

An encapsulation device having an expandable, porous body with a cavity, the body having a sealed end and a sealable end, where the body is configured to receive one or more fluids through a port in the sealable end, the body is configured to expand to conform to a shape of a target, and where the sealable end may be sealed to prevent leakage into the body, and a method if using the encapsulation device, is disclosed. The body may comprise porous membrane including expanded Polytetrafluoroethylene (ePTFE), polyester fiberfill, metal/polymer mesh, and perforated or porous polymer/metal. The target may include a location within the human body. The port in the sealable end is configured to receive a first fluid into the cavity to expand the body to conform to the shape of the target, and the port is further configured to receive a second fluid into the cavity which displaces the first fluid by diffusing the first fluid through the pores in the body and which cures (such as, by an ultraviolet light source) to secure the body to the target. Optionally, the introduction of the second fluid may be unnecessary when the first fluid includes the desired filler material for the encapsulation device.

The invention discloses a method to manufacture polytetrafluoroethylene film material used for air degerming. The invention mixes polytetrafluoroethylene resin powder and liquid lubricant, and is gained after extruding, rolling, longitudinal stretching, lateral stretching and hot shaping. It is simple technology and low cost. It could be used for air degerming and has great social and economic benefits.

A composite stent graft has a balloon expandable stent portion ( 3 ), a tubular graft material portion ( 1 ) inside or outside of the balloon expandable stent portion and self expanding stents ( 5 ) associated with the tubular graft material portion. Part ( 7 ) of the balloon expandable stent portion can extend beyond the proximal end ( 9 ) of the tubular graft material portion. The tubular graft material can be polytetrafluoroethylene, Dacron, Thoralon(TM), polyamide, small intestine submucosa, collagenous extracellular matrix material, or any other suitable biocompatible material. A method of deploying which includes flaring a part ( 7 ) of the balloon expandable stent portion is also discussed.

A system and method for selective masking of stents using an expandable masking balloon to prevent deposition of therapeutic or protective coatings on portions of the stent during a coating application process. An expandable balloon is located within the inner region of a stent, the balloon is inflated until its outer surface contacts and the inner surface of the stent lattice in the areas in which the stent coating is not to be applied, thereby masking the stent inner surface from deposition of stent coating material during a stent coating process, and the coating is applied to the remaining exposed surfaces of the stent, for example by spraying or dipping the stent. The balloon is then deflated and removed from the coated stent. The balloon may be coated with, or formed from, a material impregnated with polytetrafluoroethylene to discourage adherence of the coating material to the balloon's outer surface in order to minimize coating waste and bridging of stent lattice openings by coating films.

Provided herein is a composite, comprising: a polymer host selected from the group consisting of low-density polyethylene (LDPE), linear low-density polyethylene (LLDPE), polyethylene terephthalate (PET), polytetrafluoroethylene (PTFE), and polypropylene (PP), polyurethane, polycaprolactone (PCL), polydimethylsiloxane (PDMS), polymethylmethacrylate (PMMA), and polyoxymethylene (POM); and a guest molecule comprising hyaluronic acid; wherein the guest molecule is disposed within the polymer host, and wherein the guest molecule is covalently bonded to at least one other guest molecule. Also provided herein are methods for forming the composite, and blood-contracting devices made from the composite, such as heart valves and vascular grafts.

An apparatus is provided that includes a graft for coupling two vascular conduits within a patient. The graft includes: 1) an anchor system that forms an arc at one end of the conduits; and 2) a body element coupled to the anchor system. The anchor system comprises a biodegradable stent. In particular embodiments, portions of the graft are either self-expandable or balloon-expandable. In still other embodiments, anchor system includes NITINOL and the anchor system is substantially self-sealing at one end of the conduits. In one embodiment, the body element comprises polytetrafluoroethylene (PTFE) or expanded polytetrafluoroethylene (EPTFE). In yet other embodiments, the body element includes either a gelatinous or an elastomeric coating disposed on its surface.

The invention discloses carbon fiber reinforced thermoplastic resin composite material which is composed of the components according to the percentage by weight: carbon fibers with the surface modified accounting for 5 percent to 50 percent, thermoplastic resin accounting for 44 percent to 75 percent, polytetrafluoroethylene accounting for 5 percent to 15 percent and processing auxiliary agent accounting for 1 percent to 5 percent; the carbon fibers with the surface modified is manufactured by processing the carbon fibers in specially mixed acidic solution under the temperature of 40 DEG C to 80 DEG C for 30 minutes to 120 minutes and dried at the temperature of 80 DEG C to 150 DEG C. The invention also discloses the preparation method of the carbon fiber reinforced thermoplastic resin composite material. The carbon fibers of the carbon fiber reinforced thermoplastic resin composite material provided by the invention are dispersed in a state of 3 mm to 5 mm in a resin matrix, the original high intensity of the carbon fibers is maintained to the maximum, so as to ensure the prepared composite material to have high intensity, high modulus, high heat resistant and high wear resistant performances.

The invention discloses a preparation method for high strength macro graphene conductive fiber. According to the method, graphite is oxidized to obtain a graphene oxide; the graphene oxide is dispersed in water or a polar organic solvent to prepare a spinning liquid sol with the mass concentration of 1-20%; the spinning liquid sol is transferred to a spinning device; the spinning liquid is continuously extruded from a spinning head capillary at a uniform speed; the extruded spinning liquid enters a solidification liquid; the solidified primary fiber is collected by using a polytetrafluoroethylene roller; a drying treatment is performed to obtain the graphene oxide fiber; the graphene oxide fiber is subjected to chemical reduction to obtain the graphene fiber. According to the present invention, the spinning process is simple; the operation is performed at the room temperature; no strong corrosive reagent is used; the process has the characteristics of green environmental protection; the prepared graphene fiber has characteristics of good conductivity, excellent mechanical property and good toughness, can be woven into the pure graphene fiber cloth, can further be woven into various fabrics with other fibers, and can further be added to the polymer as the conduction enhancing additive and the like; the prepared graphene fiber can replace the carbon fiber to use in a plurality of fields.

The invention belongs to the field of modified polypropylene composite materials and relates to a scratch-resistant modified polypropylene composite material which is applicable to manufacturing automotive interior parts and comprises the following components by parts by weight: 60-90 parts of polypropylene, 5-20 parts of plasticizer, 5-20 parts of mineral filler, 0.1-4 parts of wear-resistant agent/scratch-resistant agents and 0.1-3 parts of additives, wherein the wear-resistant agent/scratch-resistant agents can be selected from the mixture of nano-polytetrafluoroethylene superfine micro-powder, organic matter-modified siloxane, modified silicone mixture and reactive modified polysiloxane. The prepared modified polypropylene composite material has high surface gloss and better impact-resistant performance, strength, melt fluidity and mechanical performance; furthermore, due to the use of the various wear-resistant agents/scratch-resistant agents, the scratch-resistant performance of the product is excellent; and the resources of the required raw materials are simultaneously extensive and easy to obtain.

An article of manufacture and a process for making the article by the anodization of aluminum and aluminum alloy workpieces to provide corrosion-, heat- and abrasion-resistant ceramic coatings comprising titanium and/or zirconium oxides, and the subsequent coating of the anodized workpiece with polytetrafluoroethylene (“PTFE”) or silicone containing coatings. The invention is especially useful for forming longer life PTFE coatings on aluminum substrates by pre-coating the substrate with an anodized layer of titanium and/or zirconium oxide that provides excellent corrosion-, heat- and abrasion-resistance in a hard yet flexible film.

A gas diffusion electrode and method of making the same. According to one embodiment, the electrode comprises a support layer, a first cushioning layer positioned on top of the support layer, a second cushioning layer positioned on top of the first cushioning layer, and a catalyst layer positioned on top of the second cushioning layer. The support layer is a mechanically stable, electrically-conductive, gas porous substrate, such as carbon fiber paper. The first cushioning layer, which is also gas porous, comprises a non-woven mat of electrically-conductive, chemically-inert fibers, preferably carbon nanofibers, bound together with a polymeric binder, such as polytetrafluoroethylene. The second cushioning layer is similar to the first cushioning layer, except that carbon black or a similar electrically-conductive, chemically-inert particulate material is included in addition to or instead of the fibrous material for the purpose of fine-tuning pore size.

A non-aqueous electrolyte secondary battery including a positive electrode, a negative electrode, a separator interposed between the positive and negative electrodes, and a non-aqueous electrolyte. The negative electrode includes composite particles and a binder. Each of the composite particles includes: a negative electrode active material including an element capable of being alloyed with lithium; carbon nanofibers that are grown from a surface of the negative electrode active material; and a catalyst element for promoting the growth of the carbon nanofibers. The binder comprises at least one polymer selected from the group consisting of polyimide, polyamide imide, polyamide, aramid, polyarylate, polyether ether ketone, polyether imide, polyether sulfone, polysulfone, polyphenylene sulfide, and polytetrafluoroethylene.

A composite multilayer implantable material having a first inner tubular layer formed of expanded polytetrafluoroethyene having a porous microstructure defined by nodes interconnected by fibrils, wherein said first layer has a plurality of pleated folds, a second tubular layer formed of textile material circumferentially disposed exteriorly to said first layer; and having an elastomeric bonding agent applied to one of said first layer or second layer and disposed within the pores of said microstructure for securing said first layer to said second layer.

The invention relates to medical devices and methods of using them. The devices are prostheses which can be percutaneously deliverable with (or on) an endovascular catheter or via other surgical or other techniques and then expanded. The prostheses are configured to have a lattice resistant to dilation and creep, which is defined by a plurality of openings. The prosthesis may also optionally have a stent disposed proximal to the lattice. In exemplary embodiments, the fluoropolymer is expanded polytetrafluoroethylene. The composite materials exhibit high elongation while substantially retaining the strength properties of the fluoropolymer membrane. In at least one embodiment, the lattice is made of a composite material that includes a least one fluoropolymer membrane including serpentine fibrils and an elastomer. A lattice including a generally tubular member formed of a composite material including a least one fluoropolymer membrane containing serpentine fibrils and an elastomer is also provided.

The fire retardant PC/ABS alloy material without halide and phosphate consists of polycarbonate 65.5-91.2 wt%, acrylonitrile-butadiene-styrene ternary copolymer 6-17 wt%, compatilizer 1.0-4.0 wt%, fire retardant PTFE 0.3-1.5 wt%, organosilicon fire retardant 1.0-8.0 wt%, diphenyl sulfone sulfonate 0.1-1.0 wt%, antioxidant 0.1-1.0 wt% and lubricant 0.2-2.0 wt%. The present invention also provides the preparation process of the alloy material. The alloy material is environment friendly, and may be applied widely in automobile industry, electronic industry, electric industry and mechanical industry.

The invention provides a bionic anti-sticking lyophobic and oleophobic pasting film and belongs to the technical field of a polytetrafluoroethylene product. The surface of a thin film layer is provided with a first-grade convex hull type structure and a second-grade convex hull type structure, wherein each convex hull type structure is formed by convex hull structure units; the bottoms of the convex hull structure units are circular, regularly triangular, regularly quadrilateral or regularly hexagonal; and a convex hull is in a bowl shape, a cylinder shape, a cone shape, a triangular prism shape, a quadrangular shape or a hexagonal prism shape. The bionic anti-sticking lyophobic and oleophobic pasting film can be randomly bent, and is used on an irregular surface to convert a previous hydrophilic and oleophilic surface into a lyophobic and oleophobic surface, so that the bionic anti-sticking lyophobic and oleophobic pasting film can be widely applied to fields including automobiles, kitchen utensils, electronic products and the like.

A composite stent-graft tubular prosthesis includes a non-continuous tubular body formed of polytetrafluoroethylene components, providing axial and circumferential compliance to said prosthesis and a circumferentially distensible stent.

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 present invention relates to systems, articles, and methods for removing water from hydrocarbon fluids. In an embodiment, the invention includes a water/fuel separation system including a filter housing and a filter element disposed within the filter housing. The filter element can include a separation article including a porous polymer layer having and a porous substrate comprising a hydrophobic surface. In an embodiment, the invention includes a filter element for separating emulsified water from a hydrocarbon fluid. In an embodiment, the invention includes a method for filtering water out of a hydrocarbon fluid including passing a hydrocarbon fluid through a separation article including a polymer layer comprising polytetrafluoroethylene; and a porous substrate comprising a hydrophobic surface, the polymer layer disposed on the porous substrate.

Modified polytetrafluoroethylene powder of a sinterable copolymer of tetrafluoroethylene containing about 0.5 to about 10 weight % of fluorinated vinyl ether, the copolymer having a melt creep viscosity of greater than about 1×10⁶ Pa·S. In preferred embodiments, the sinterable copolymer has a melt creep viscosity of greater than about 1×10⁷ Pa·S and fluorinated vinyl ether content of from about 1 to about 7 weight %. The polymer has a combination of a high level of fluorinated vinyl ether and a melt creep viscosity which is high enough to enable the fabrication of articles by sintering.

A process seal made of a material such as polytetrafluoroethylene is used as a microwave window in a radar tank level gauge. The periphery of the process seal is surrounded by a metal containment ring that is fitted to the periphery to limit the amount of expansion outwardly of the process seal material as well as provide for localized loading at the periphery for clamping pressures on the seal. Electromagnetic radiation shielding is provided not only by the containment ring, but also by an EMI shielding O-ring mounted in a groove on a sealing end of the containment ring. A process environmental O-ring is carried by the process seal in an outer shoulder groove that is enclosed by the containment ring.

The invention belongs to the field of modified polypropylene composite material, and relates to a low-VOC scratch-resistant modified polypropylene composite material which is applicable to manufacturing automobile interior trim parts, and comprises the components based on the parts by weight: 60-90 parts of polypropylene, 5-20 parts of toughening agent, 5-20 parts of mineral filler, 0.1-4 parts of odor adsorbent, 5-15 parts of wear-resistant agent/scratch-resistant agent and 0.1-3 parts of auxiliary agent, wherein the odor adsorbent is a mixture of three selected from clay, bentonite, porous silicon dioxide, activated aluminium oxide or molecular sieve; and the wear-resistant agent/scratch-resistant agent is one or a mixture of two in polytetrafluoroethylene micro powder or reaction-type polyorganosiloxane. The modified polypropylene composite material not only has better impact-resistant performance and strength, but also has excellent scratch-resistant performance and low-VOC diffusion characteristic; and the needed raw materials have wide source and can be conveniently and easily obtained.

An aqueous dispersion composition of about 30 to about 70 weight % non-melt-processible fluoropolymer particles having a standard specific gravity (SSG) of less than 2.225 and about 2 to about 11 weight % surfactant based on the weight of said fluoropolymer comprising a compound or mixture of compounds of the formula:

R(OCH₂CH₂)_nOH

wherein R is a branched alkyl, branched alkenyl, cycloalkyl, or cycloalkenyl hydrocarbon group having 8-18 carbon atoms and n is an average value of 5 to 18. The fluoropolymer particles of the dispersion comprise a core of high molecular weight polytetrafluoroethylene and a shell of lower molecular weight polytetrafluoroethylene or modified polytetrafluoroethylene. Preferably, the aqueous dispersion composition comprises about 45 to about 65 weight % non-melt-processible fluoropolymer particles.

A composite diaphragm for diaphragm pumps comprises an elastomer body and a polytetrafluoroethylene (PFTE) coating on its back side. The elastomer body has a shape of a circular dish that has an edge region with a clamping area, a bottom and a flexible section of the diaphragm that connects the edge of the dish with the bottom. The flexible section of the diaphragm comprises a multitude of naps forming elevations on the coated side of the elastomer body. The PFTE coating is a plane ring surface with the area of the flexible section of the diaphragm.

The invention discloses a method for self-lubricating treatment of laser micro-texture of bearings. The invention comprises the following steps: firstly performing laser micro-processing technology of micro recessed cavities or micro grooves on a bearing surface, and then performing molding and bonding technology by a self-lubricating composite material on the bearing surface; the self-lubricating composite material comprises the following components by mass: 10-15% of polyimide (PI); 8-13% of graphite powder; 40-50% of polytetrafluoroethylene; 25-29% of MoS2; 0-5% of additives. By the self-lubricating treatment of laser micro-texture of a bearing, the invention guarantees the bearing capacity and the fitting accuracy of the bearing, realizes an optimized distribution of the lubricant on the bearing working surface, and improves comprehensive performance of antifriction and wear resistance of the bearing under complicated working conditions.

The invention belongs to the technical field of friction material, and in particular relates to a graphene-nano polytetrafluoroethylene composite filler with a function of reducing friction, as well as a preparation method and the application of the composite filler. The composite filler comprises the following main components in parts by weight: 1 part of modified graphene and 1-20 parts of modified nano polytetrafluoroethylene; the preparation method of the composite filler comprises the following steps: separately reacting graphene and nano polytetrafluoroethylene with amination reagent and carboxylation reagent to obtain the modified graphene and the modified nano polytetrafluoroethylene; carrying condensation reaction so that the modified graphene and the modified nano polytetrafluoroethylene are connected with each other by a covalent bond to obtain the graphene-nano polytetrafluoroethylene composite filler. The function of friction reduction of the graphene and the function of lubrication of the nano polytetrafluoroethylene are utilized at the same time; after the composite filler is added to a polymer material, the friction coefficient and the wear rate of the material can be reduced, and the mechanical property of the material can be improved.