24 results about "Expanded polytetrafluoroethylene" patented technology

The invention discloses a preparation method of a high-resilience expanded polytetrafluoroethylene sealing material, and belongs to the technical field of high polymer material modification. According to the method, high-molecular-weight or modified polytetrafluoroethylene is used as a matrix, and high-orientation fibers are obtained through ultrasonic premixing, twin-screw melt extrusion, stretching and heat setting; dipping the fiber in a dispersion liquid containing high-entropy alloy nanoparticles, carbon nanotubes and graphene nanosheets, carrying out vacuum drying and gradient heat treatment to form a nano-reinforced precursor fiber, and constructing a porous anisotropic skeleton by adopting conventional or supercritical expansion and a specific weaving process; and interface strengthening and surface functionalization are realized through plasma surface treatment, silane coupling agent chemical grafting and wear-resistant coating coating. The obtained sealing material has low density, high strength, high resilience and low compression set, has excellent chemical medium resistance and anti-static performance, and is suitable for sealing parts of flanges, valves and the like under harsh working conditions of petrochemical engineering, electric power, hydrogen energy, aerospace and the like.

The invention discloses a flexible copper-clad plate with high thermal conductivity and low dielectric property and a preparation method of the flexible copper-clad plate. The flexible copper-clad plate comprises an insulating substrate, the composite film is a thermoplastic polyimide / heat-conducting low-dielectric ePTFE / thermoplastic polyimide insulating composite film which is composed of a middle layer ceramic / boron nitride-expanded polytetrafluoroethylene functional hybrid membrane and thermoplastic polyimide layers on the two sides of the middle layer ceramic / boron nitride-expanded polytetrafluoroethylene functional hybrid membrane. And the flexible conductive metal foil is compounded with the single surface, double surfaces or multiple layers of the insulating substrate through a thermal forming compounding process. Through the mode, the flexible copper-clad plate can have excellent peel strength under the adhesive-free condition through structure optimization and process innovation, low dielectric constant and low dielectric loss tangent value can be realized under the high-frequency condition, and meanwhile, the heat conductivity coefficient is remarkably improved. And through continuous production, the efficiency is greatly improved, and a high-reliability base material is provided for the high-end electronic fields such as new energy vehicles, 5G / 6G communication and wearable equipment.

The utility model relates to a waterproof and breathable masking paper composite adhesive tape which comprises a reel and an adhesive tape body, the adhesive tape body is of a four-layer structural design and comprises an anti-sticking layer, a base material layer, a waterproof and breathable layer and an adhesive layer which are sequentially connected from the outer layer to the inner layer, the manufacturing process of the adhesive tape is simplified, and the production efficiency is improved; the anti-sticking layer comprises polytetrafluoroethylene and a titanium dioxide / graphene coating and is used for improving the anti-sticking effect and the ultraviolet-proof performance of the adhesive tape; the waterproof breathable layer comprises expanded polytetrafluoroethylene and nanofibers and is used for improving the waterproof and breathable performance of the adhesive tape and ensuring that the stable effect can be kept in various environments; the adhesive layer comprises polyurethane, a water-based acrylic pressure-sensitive adhesive and an organic silicon modifier, and nano silicon dioxide is uniformly distributed in the water-based acrylic pressure-sensitive adhesive; the adhesive force of the adhesive tape can be improved, cohesive strength is enhanced, weather resistance is improved, aging is delayed, degumming and wiredrawing phenomena are reduced, adhesive residues are reduced, and use experience is improved.

Expanded polytetrafluoroethylene (ePTFE) monofilaments with superior knot pull tensile strength are described herein, which can be used as sutures and in medical devices such as for tethers and anchors for cardiac repair. The properties of these monofilaments balance the need for an inert, soft, lubricious and porous material with sufficient tensile properties for high strength applications.

This utility model discloses a device for adjusting the local hardness of expanded polytetrafluoroethylene (ePTFE) sheets, including a support platform, a heating plate, a support structure, and a power module. The heating plate is disposed on the upper side of the support platform. The device further includes: a compression array plate, which is fixed above the heating plate by the support structure and has multiple independent pressure heads on its lower side. The pressure heads are arranged in a matrix, and each pressure head can extend and retract independently in the vertical direction and is equipped with an independent pressure adjustment mechanism; and an intelligent control module, which is powered by the power module and configured to drive the pressure heads to work through the pressure adjustment mechanism according to set pressure parameters. The device for adjusting the local hardness of ePTFE sheets provided by this utility model can locally, reversibly, and dynamically adjust the hardness of ePTFE sheets through a dual mechanism of mechanical compression and thermal energy regulation.

The utility model discloses an expanded polytetrafluoroethylene clamping and wrapping tooth-shaped gasket which comprises a main sealing ring and further comprises an auxiliary sealing ring and an outer reinforcing ring. The auxiliary sealing ring coaxially sleeves the inner side of the main sealing ring; and the outer reinforcing ring coaxially sleeves the outer side of the main sealing ring. The internal main body of the main sealing ring is a metal tooth-shaped framework, and the cross section of the end face is tooth-shaped. The outer side end of the metal tooth-shaped framework is covered with an elastic polytetrafluoroethylene pad. The inner side wall of the main sealing ring is provided with a main sealing ring inner convex rib which is convex inwards, and the outer side wall of the auxiliary sealing ring is provided with an auxiliary sealing ring matching groove which is concave inwards; and the main sealing ring inner convex rib is matched and clamped with the auxiliary sealing ring matching groove. And a gap is formed between the matching of the inner convex rib of the main sealing ring and the matching groove of the auxiliary sealing ring in the axial direction. A concave main sealing ring outer groove is formed in the outer side wall of the main sealing ring, and the inner side of the outer reinforcing ring is connected with the main sealing ring outer groove in a matched and clamped mode. The scheme has the beneficial effects that the inner ring and the outer ring are additionally arranged on the inner ring and the outer ring of the main sealing ring respectively, so that the low-dissipation sealing requirement is met.

The application discloses a cutting die for expanded polytetrafluoroethylene plate, which comprises a base, a support fixed on the base, a rotating rod penetrating through the support and rotationally connected with the support, the other end of the rotating rod being rotationally connected with the support, a driving mechanism installed on the support and used for driving the rotating rod to rotate intermittently, a through groove arranged at the upper end of the support, a bolt and nut assembly slidably connected in the through groove and capable of being positioned, the bolt and nut assembly being fixedly connected with the upper end of a sliding block, and the rotating rod being sleeved with the sliding block movably connected with the rotating rod. The application can cut the plate at equal intervals without marking the plate by workers, greatly improves the work efficiency, clamps the plate, does not need manual positioning of the plate, increases the stability of the plate, reduces the labor of the workers, and can adjust the position of the cutter to meet the cutting of plates with different lengths and the cutting accuracy.

This invention relates to a membrane-based heat exchanger (MemHEX) tailored for tropical climates to address challenges in indoor air quality, thermal comfort, and energy efficiency. The device features a thermally insulated hexagonal housing that optimizes airflow, minimizing turbulence and pressure drop. At its core, a quasicounterflow arrangement of hexagonal plates is integrated with a sandwich-like assembly of expanded polytetrafluoroethylene (ePTFE) membranes and spacers. This design facilitates the efficient transfer of both sensible and latent heat while maintaining separate pathways for exhaust and supply air. The MemHEX includes supply and exhaust fans strategically positioned to ensure uniform airflow across the heat exchanger core. Environmental sensors automate fan operation, regulating ventilation based on real-time conditions such as temperature, humidity, or air quality. The system also includes high-efficiency particulate air (HEPA) filters for pollutant-free operation. Scalable and efficient, the MemHEX is suitable for residential, commercial, and industrial applications.

The present application provides self-supporting, uniaxially expanded polytetrafluoroethylene (ePTFE) films having high intrinsic strength, high matrix modulus, and high crystallinity index. In some embodiments, the ePTFE films are stretched in the machine direction. The uniaxially oriented ePTFE films have a matrix tensile strength in the machine direction of at least about 1000 MPa, a matrix modulus at ambient temperature (i.e., about 20°C) of at least about 100 GPa, and a crystallinity index of at least about 94%. In some embodiments, the ePTFE films have a tenacity greater than or equal to about 5 gf / d and a denier less than or equal to about 750 g / 9000 m. Further, the uniaxially oriented ePTFE films have a Gurley number of at least about 0.98 <p2>Orientation. In addition, the fibrils in ePTFE films are nearly perfectly aligned in parallel. ePTFE films can be used to form composites, laminates, fibers, tapes, sheets, tubes, or other three-dimensional objects.< / p2>

The invention discloses an accelerated life test method for expanded polytetrafluoroethylene for aviation, and belongs to the technical field of aircraft maintenance and detection. Comprising the following steps: mounting a sample, and performing at least one accelerated working condition simulation test including repeated compression, medium soaking, heat-moisture treatment, salt spray corrosion, solar radiation and the like; performing thermal aging on the test sample subjected to the simulation test at different temperatures; testing the mechanical property of the sample after thermal aging, and determining a critical value of the mechanical property by taking sealing failure as a judgment standard; and calculating the time when the performance reaches the critical value at different temperatures, and drawing an Amenius diagram to obtain the service life. According to the test method, complex working conditions can be accurately simulated, the service life of the material is efficiently obtained through scientific testing and calculation, a basis is provided for safe replacement of expanded polytetrafluoroethylene for aviation, the problems that a traditional method is difficult to adapt to actual scenes and service life prediction is not accurate are solved, and the reliability of an aircraft sealing system is guaranteed.

This invention discloses a flexible, bendable composite pipe with spring support for ePTFE membrane winding, its preparation method, and its applications. The composite pipe includes a spring support body; multiple layers of ePTFE expanded polytetrafluoroethylene (ePTFE) membrane wound around the outer surface of the spring support body; the multiple ePTFE membranes are crystalline-linked by a hot-melt sintering process to form fluorocarbon bonds, thus combining the multiple ePTFE membranes with the spring support body to form a composite pipe wall structure. This structure solves the problems of collapse and loosening caused by the softness and deformation of single-layer ePTFE membranes, endowing the pipe with good tensile strength, flexible bending characteristics, and air permeability / filtration functions due to the microporous structure of ePTFE. The pipe is resistant to chemical corrosion and has a wide temperature adaptability range, making it suitable for industrial fluid transport and filtration systems requiring flexible conveying, pressure balance, or the infiltration / emission of specific gases. The preparation method mainly includes winding and hot-melt sintering processes within a specific temperature range.

The invention discloses a preparation method of an expanded polytetrafluoroethylene sealing material with conductivity and elasticity, and belongs to the technical field of energy conservation and environmental protection. The method comprises the following steps: carrying out silane coupling and ultrasonic dispersion on nano-silver and graphene in an ethanol medium to form a nano conductive composite dispersion liquid; the preparation method comprises the following steps: mixing polytetrafluoroethylene with a volatile lubricant, performing, performing extrusion-two-way stretching, and sintering to obtain a conductive framework; the framework is subjected to fluororubber emulsion vacuum impregnation and drying, then vulcanization is performed under hot pressing, and foaming forming is performed in the nitrogen atmosphere; perfluoroalkylsilane surface modification is performed to improve hydrophobicity. The obtained sealing material forms a continuous conductive network in a node-fiber microstructure, micropores are filled with elastomers, and the sealing material is suitable for electronic equipment, electric automobiles, chemical engineering, aerospace and other scenes needing conductive shielding and dynamic sealing. The method is simple in process, controllable in parameter, environment-friendly and suitable for large-scale production.

The utility model relates to the technical field of electric power protection, and discloses an electric power protection sleeve, which comprises a sleeve structure and a connecting structure, the main body of the sleeve structure is a pipe body made of chlorinated polyvinyl chloride, and the pipe body is provided with an air hole for maintaining the internal air pressure of the pipe body. A breathable film integrally formed with the pipe body through a hot pressing process is arranged at the position of the breathable hole, and an anti-collision net is further fixedly arranged on the side wall of the breathable hole and located on the outer layer of the breathable film. The connecting structure comprises a check block fixedly installed on the outer surface of the pipe body and a magnet embedded in the end face of the pipe body. According to the electric power protection sleeve, a gas-permeable membrane made of ePTFE (expanded polytetrafluoroethylene) is embedded in the non-pressure-bearing side of a sleeve body, the outer layer of the gas-permeable membrane is covered with a metal anti-collision net, the aperture of the ePTFE membrane is 0.1-1 micrometer, gas can be allowed to pass through the ePTFE membrane, liquid water and dust are blocked, the gas-permeable membrane and the sleeve body are seamlessly combined through the hot pressing technology, and the gas-permeable membrane is not prone to falling off. And reduction of mechanical strength caused by traditional trepanning is avoided.

The invention provides a dynamic rolling compensation sintering method for preparing an expanded polytetrafluoroethylene plate, which comprises the following steps: coating a biaxially oriented polytetrafluoroethylene film on a steel roller from an unreeling machine, and controlling the rotating speed of the steel roller and the advancing speed of the film on the unreeling machine, so that the expanded polytetrafluoroethylene film has a certain tension force; therefore, the steel roller is tightly coated with the thin film, and the thin film layers are tightly attached to each other. After wrapping is finished, the steel roller coated with the polytetrafluoroethylene film is put into a sintering furnace to be sintered, during sintering, the expanded polytetrafluoroethylene film is continuously rolled through a pressure roller above the steel roller, parameters such as the thickness and the surface density of the expanded polytetrafluoroethylene film are corrected in real time, and the expanded polytetrafluoroethylene film is obtained. Therefore, the consistency of the performance indexes of the expanded polytetrafluoroethylene plate is realized. The expanded polytetrafluoroethylene plate or strip produced by the method is simple in process requirement and high in production efficiency.

Expanded polytetrafluoroethylene (ePTFE) monofilaments with superior knot pull tensile strength are described herein, which can be used as sutures and in medical devices such as for tethers and anchors for cardiac repair. The properties of these monofilaments balance the need for an inert, soft, lubricious and porous material with sufficient tensile properties for high strength applications.

The invention provides an anion exchange membrane, a preparation method thereof and a water electrolysis hydrogen production device, and belongs to the technical field of water electrolysis hydrogen production, and the anion exchange membrane comprises a supporting layer and a homogeneous layer located on at least one side in the thickness direction of the supporting layer. The homogeneous layer comprises anion exchange resin, and the supporting layer comprises a porous base material and anion exchange resin filled in the porous base material. Wherein the anion exchange resin comprises a compound as shown in a formula I, and the material of the porous base material comprises at least one of polyether-ether-ketone, polyphenylene sulfide, polyphenylene sulfone, polyether sulfone, polypropylene, polyethylene, polyethylene glycol terephthalate, polytetrafluoroethylene, expanded polytetrafluoroethylene and a liquid crystal polymer. The anion-exchange membrane provided by the embodiment of the invention has high ionic conductivity and good pressure resistance, so that the anion-exchange membrane can meet the requirement of high pressure and realize long-term stable operation while ensuring the water electrolysis efficiency.

The invention relates to the technical field of fuel cell diaphragms, in particular to an enhanced composite proton exchange membrane based on hydrophobic phase modification and a preparation method thereof, and the preparation method comprises the following steps: synthesizing fluoride-SiO2 nanoparticles, and mixing with a perfluorosulfonic acid resin solution to obtain a membrane preparation solution. Then coating a glass substrate with the membrane-making liquid, covering a membrane-making liquid layer with an expanded polytetrafluoroethylene base membrane with the periphery fixed, then coating the base membrane layer with the membrane-making liquid, and finally performing high-temperature curing to obtain the composite proton exchange membrane. By introducing the fluorine-SiO2 nanoparticles and the expanded polytetrafluoroethylene skeleton, the prepared composite proton exchange membrane has relatively high mechanical strength, dimensional stability and proton conductivity under a triple enhancement effect.

The application provides a composite proton exchange membrane and a preparation method and application thereof. The composite proton exchange membrane comprises an expanded polytetrafluoroethylene fiber membrane and perfluorosulfonic acid resin particles distributed among the pores of the expanded polytetrafluoroethylene fiber membrane. The perfluorosulfonic acid resin particles are directly compounded with polytetrafluoroethylene to form a composite reinforced structure, and the perfluorosulfonic acid resin particles are uniformly dispersed inside the pores of the expanded polytetrafluoroethylene fiber membrane, which can effectively improve the filling performance of ePTFE and perfluorosulfonic acid resin particles, thereby improving the anti-swelling performance of the composite proton exchange membrane, reducing the dissolution of perfluorosulfonic acid resin, and also effectively reducing the amount of perfluorosulfonic acid resin and improving the service life and durability of the composite proton exchange membrane.

The present application provides self-supporting uniaxially expanded polytetrafluoroethylene (ePTFE) membranes having high intrinsic strength, high matrix modulus, and high crystallinity index. In some embodiments, the ePTFE membrane is stretched in the machine direction. The uniaxially oriented ePTFE film has a matrix tensile strength in the machine direction of at least about 1000 MPa, a matrix modulus of at least about 100 GPa at ambient temperature, i.e. About 20 DEG C, and a crystallinity index of at least about 94%. In some embodiments, the ePTFE film has a toughness of greater than or equal to about 5 gf / d and a denier of less than or equal to about 750 g / 9000 m. In addition, the uniaxially oriented ePTFE film has a lt of at least about 0.98; p2gt, P2gt; and orientation. In addition, the fibrils in the ePTFE membrane are approximately perfectly arranged in parallel. The ePTFE films may be used to form composite materials, laminates, fibers, tapes, sheets, tubes, or other three-dimensional objects.

The utility model relates to the technical field of back adhesive tapes, in particular to an expanded polytetrafluoroethylene back adhesive tape. The utility model relates to an expanded polytetrafluoroethylene back adhesive tape which comprises an expanded polytetrafluoroethylene film and an adhesive layer arranged on the expanded polytetrafluoroethylene film, the expanded polytetrafluoroethylene film comprises a first surface and a second surface; the first surface is in contact with the adhesive layer, and the second surface deviates from the adhesive layer; the first surface is a hydrophilic expanded polytetrafluoroethylene membrane surface, and the second surface is a hydrophobic expanded polytetrafluoroethylene membrane surface. According to the expanded polytetrafluoroethylene back adhesive tape material provided by the utility model, the hydrophilic surface of the expanded polytetrafluoroethylene film is contacted with the adhesive layer, so that the bonding effect of the expanded polytetrafluoroethylene film and the adhesive layer is improved, the expanded polytetrafluoroethylene film is not easy to fall off in use, and the service life of the expanded polytetrafluoroethylene back adhesive tape material is prolonged.

The utility model provides a water-repellent elastic breathable sticker, which belongs to the technical field of material science and comprises a protective layer, an antibacterial layer fixedly connected to the bottom of the protective layer, a water-repellent layer fixedly connected to the other side of the antibacterial layer and a first adhesive layer fixedly connected to the bottom of the water-repellent layer. The stretching assemblies are arranged on the two sides of the main body assembly. The protective layer made of polyester materials and the antibacterial layer made of polyester fiber silver ion carriers jointly prevent bacteria from invading, and the infection risk is reduced; the water repellent layer made of the expanded polytetrafluoroethylene material not only can prevent liquid water from permeating, but also can keep air permeability; the first bonding layer made of a pressure-sensitive adhesive material provides rapid and efficient bonding, so that the effect of improving the safety of the adhesive tape is achieved; through cooperation of all parts in the stretching assembly, it can be ensured that the adhesive tape still keeps stable adhesiveness during stretching, and stress concentration is reduced through the shaped notches, so that the ductility and use comfort of the adhesive tape are improved.

According to the shrinkage and infiltration prevention tool, the outer peripheral edges of expanded sheets such as expanded polytetrafluoroethylene materials are folded into a gap between the outer peripheral wall of an inner frame and the inner peripheral wall of an outer frame, and then the outer frame and the inner frame are detachably connected, so that the expanded sheets are clamped and fixed; in this way, the outer peripheral edges of the puffed sheets are evenly fixed, the fixing effect is good, operation is convenient, the shrinkage uniformity in the infiltrating and drying process can be improved, and then the product yield is increased.

1. A composite material (10) comprising an expanded polytetrafluoroethylene layer (12), a densified expanded polytetrafluoroethylene layer (16a) bonded to the expanded polytetrafluoroethylene layer, a porous expanded polytetrafluoroethylene layer (16b) bonded to the densified expanded polytetrafluoroethylene layer, an adhesive (16c), and a densified expanded polyethylene layer (14), wherein the adhesive bonds the expanded polyethylene layer to the porous expanded polytetrafluoroethylene layer.

This invention discloses a processing equipment for expanded polytetrafluoroethylene (ePTFE) gaskets, comprising a support frame, a hydraulic cylinder mounted on the support frame, a pressing cylinder fixed to the output end of the hydraulic cylinder, a support column intermittently rotatably connected to the upper end of the support frame and cooperating with the output end of the hydraulic cylinder, a circular plate fixedly connected to the upper end of the support column, the upper end of the circular plate having multiple forming grooves arranged in a ring array and cooperating with the pressing cylinder, a circular ring with an arc-shaped concave surface at the lower end of the circular plate, and an ejection mechanism for ejecting the formed gasket within the forming grooves. This invention allows for continuous pressing of PTFE rings, avoiding the drawbacks of existing technologies that require manual filling and have low work continuity, thus reducing the workload of workers. Furthermore, it allows for the stacking of PTFE rings without manual intervention.