Polymer and elastomer compositions having carbon nanostructure additives, and articles formed therefrom for use in EMI and RFI shielding and pressure-sensitive seals having quantum tunneling composite effects.

Abstract

Disclosed are compositions of at least one matrix polymer, which may be a thermoplastic polymer and / or a curable polymer having at least one functional group for crosslinking, for use in forming articles, and methods for making such articles, wherein the compositions and methods include three-dimensional, branched, and crosslinked carbon nanostructure additives. In one embodiment, the resulting articles can achieve volume resistivity levels of about 0.5 ohm-cm or less, which are useful for applications requiring sufficient conductivity to provide electromagnetic and / or radio frequency interference shielding. In other embodiments, other articles formed using the compositions disclosed herein can demonstrate dissipative and / or quantum tunneling effects, and are therefore useful as self-sensing pressure-sensitive articles, such as self-sensing seals.

Description

[Technical Field]

[0001] Cross-references to related applications

[0002] This U.S. non-provisional patent application claims the benefit of U.S. Provisional Patent Application No. 63 / 122,911, filed 8 December 2020, entitled “Polymer and Elastomer Compositions Having Carbon Nanostructure Additives and Articles Formed Therefrom for Use in EMI and RFI Shielding and in Pressure Sensing Seals Having Quantum Tunneling Effects,” filed under 119(e) of the U.S. Patent Act, the full disclosure of which is incorporated herein by reference.

[0003] Background of the Invention Field of Invention The present invention relates to beneficial polymer and elastomer compositions, including compositions formed from curable fluorinated and perfluorinated compositions, and to end products derived therefrom, wherein the resulting articles, such as seals and gaskets, incorporate various levels of carbon nanostructures that enable specific electromagnetic shielding properties, particularly at high filler levels, without significant particle size reduction, and further, to the field of end products that enable the formation of “smart” articles formed using these materials to evaluate the performance of the articles in real time by monitoring the conductivity of the material over time as a function of its bulk resistivity, when used in various end applications, particularly semiconductor applications. [Background technology]

[0004] Description of related technologies Conductive polymers and elastomers are known whether or not they contain intrinsically conductive polymers such as polyaniline, or they are prepared using conductive metal or carbon powders and / or particulate fillers and / or fiber fillers, which may include metals, polymers, carbon, graphite, and similar materials. Such polymers and elastomers are known for use in radio frequency interference (RFI) and / or electromagnetic interference (EMI) shielding, with high filler content, for shielding components of seals, gaskets, and other components to prevent damage from interference signals. They are also known for dissipative applications, such as vehicle exterior components, where it is important to avoid the risk of sparks and fires by discharging static charge from certain polymers to the ground, in varying amounts. While polymer and elastomer compositions with conductive or dissipative properties are used in a variety of applications, the field still needs improvement of such materials in various end-uses and the creation of novel and important end-uses, such as the use of such materials in cleanroom environments. Furthermore, new fields and uses of such compositions have not yet been developed.

[0005] Various components and elements used in semiconductor manufacturing, particularly slit valves and gate valve doors, as well as other seals and gaskets, are well known. Regarding slit valves and gate valve doors, such doors seal or gaskets to close surfaces within semiconductor manufacturing equipment, ensuring that impurities remain outside the reaction chamber and reactants originating within the chamber do not leak out. However, such reaction chambers need to be opened and closed during manufacturing to allow wafers for manufacturing chips and similar target substrates to enter and exit the chamber. In one preferred design, the seals for such slit and gate valves are incorporated into a bonding assembly called a bonding gate valve or bonding slit valve ("BSV"). The goal in such cases is to minimize the level of particle size, as particle size can cause contamination in the process. In some cases, particle release may occur as the seal degrades, and the final sealing properties generally tend to deteriorate over time. Therefore, measuring the reliability of the seal and minimizing particle size is a highly desirable characteristic in most semiconductor manufacturing applications.

[0006] Measuring the reliability and degradation rate of seals and gaskets is also a desirable ultimate goal for maximizing the effective manufacturing life of seals or gaskets while minimizing the final impact of degradation-induced leaks or compromised sealing properties across a wide range of end applications.

[0007] BSVs and other seals can be affected in various ways by different reactants and different reactant states. Such slit valves incorporating doors and seals operate in a valve that acts to open and close a door over a “slit” opening to the chamber. The seal is provided to seal the opening or slit in the chamber and to seal the opening in the chamber when the valve is in the closed position. When the valve is open, substrates for semiconductor manufacturing pass through the slit into and out of the processing chamber.

[0008] Rough precursors, plasma, high temperatures, and other conditions can cause wear on various types of seals at varying rates. Most such reaction chambers operate under vacuum conditions, and seals are used throughout the system to maintain a vacuum environment.

[0009] Such seals are generally formed from highly chemically resistant elastomer materials, making them expensive to purchase, and therefore, it is understandable that replacing them before a replacement is indicated is not always desirable. However, because the effects of reactants and conditions on the various elastomer materials used in the manufacture of seals vary, predicting when a seal will fail and / or when it will experience an imminent failure is not always easy. The sealing properties of the elastomer and other physical properties of the material can be tested, failures in various environments can be estimated, and this information can be used to obtain information about the expected lifespan of the seal. However, because predictions of environments, conditions, and usage vary, it is expected, for safety reasons, to replace the seal before failure, inconsistency in product results, or failure to a particular product occurs.

[0010] Products manufactured in such environments are inherently very expensive to produce, so unnecessary maintenance downtime and / or malfunctions are even more costly for manufacturers than replacing seals. Therefore, effective seal life is a critical factor that affects chamber operating time, chamber usage, maintenance schedules, and product failure due to deterioration of seal materials. Chemicals, temperature, and other processing conditions affect the materials of seals and doors, and mechanical stress is generated by valve operation, all of which can lead to seal deterioration and failure.

[0011] Such problems also occur in other industries where maintenance costs, sealing costs, or downtime are high, and / or sealing functionality is key to operational safety, thus making monitoring seal life and cost-effective, timely replacement crucial. In areas where particulate matter is a concern, such as the semiconductor or pharmaceutical industries, and other manufacturing cleanroom environments, minimizing such contamination is also important.

[0012] One way to address the expected seal life in prior art is through testing, which may incur additional costs and / or effort. Monitors are also sometimes installed in the reaction chamber to monitor changes in the chamber's condition that could affect the manufacturing process. The reactants are also monitored. Degradation is usually recognized by detecting the presence of vacuum leaks or particle formation from degraded seal materials.

[0013] However, if there were a way to successfully determine when a seal is damaged and / or affects processing, and when maintenance is required, these problems could be mitigated, costs reduced, and malfunctions minimized. Furthermore, if there were a way to maximize seal life while avoiding the drawbacks caused by the aforementioned seal degradation, operations could be improved.

[0014] For downhole applications in oilfield areas, a seal providing feedback is described in prior art, for example, U.S. Patent Application Publication 2017 / 0130562(A1), which teaches a seal in a well and other components used in a wellhead assembly with sensors embedded in the seal, to acquire data that can be used to determine and monitor the condition of the seal by monitoring physical operating conditions and stress or strain on the seal. This data is used to determine when the seal should be replaced periodically, regardless of the condition of the seal. The collected data is compared to baseline data using a data analyzer and predictive algorithm to evaluate the expected performance characteristics of the seal. Antennas and RFID tags or wear sensors may also be incorporated. Sensors may also be embedded in the packaging.

[0015] Other prior art attempts to monitor seal life or use sensors and other detectors in semiconductor processing processes include, for example, placing sensors on slit valves and sealing plates to monitor processing conditions, but such attempts more generally focus on monitoring to ensure proper transport and positioning of substrates within a chamber while avoiding damage to the door function, door pressure, or the substrates being processed entering or exiting the door. Such patents insert or incorporate sensors in isolation within or on the seal, or between chambers and / or inside and outside the chamber or door, to monitor differential pressure.

[0016] U.S. Patent No. 7,841,582(B2) describes a method and apparatus for controlling the pressure on a slit valve door using an actuator that applies different pressure to the actuator and door during cleaning, in contrast to during a reaction in which the internal pressure is higher than during cleaning, and as a result the seal is not unnecessarily in a high vacuum state during cleaning.

[0017] U.S. Patent No. 8,815,616 describes a slit valve unit comprising a housing around a slit valve, and a series of packing units (O-ring seals) for making the area airtight. A small conduit communicates with the airtight area between the seals and with a sensor unit that can monitor pressure changes to prevent explosion or leakage of process gases, and with a control unit that can shut down the unit to prevent events.

[0018] U.S. Patent No. 9,347,495 includes a bearing assembly formed using an inlet IC chip, an antenna connected to the chip, and RFID having a magnetic sheet function embedded in either the bearing seal or the raceway ring.

[0019] U.S. Patent No. 8,282,013 describes an embedded RFID transponder that is centrally located within a seal and subsequently vulcanized. The seal is described as being able to communicate via an RFID transducer that can thus be programmed to include information about the seal (part number, serial number, batch number and / or lot number, code, dimensions, manufacturing date or sale date, installation date and / or expiration date).

[0020] U.S. Patent No. 7,398,692 relates to a circuit chip integrated into an O-ring seal having an information transmission means for transmitting information to the outside of the sealing ring. The chip is sandwiched in a notch in the seal body, and then the notch is fixed. Wiring attached to the sensor is routed out from the body and connected to a pressure measuring device. Pressure monitoring is evaluated and internal seal stress is measured, and when the seal reduces the internal stress to 80%, the seal is removed from use.

[0021] U.S. Patent Application Publication No. 2018 / 0052104(A1) describes the use of a component wear indicator material that can be placed in various locations within a chamber. The wear indicator has various layers and phosphorescent material that indicate wear.

[0022] U.S. Patent No. 9,975,758 includes a microsensor that can be mounted on a wafer processing apparatus to monitor various conditions in real time. The microsensor may also be placed throughout the processing chamber and on the surface of the apparatus.

[0023] U.S. Patent No. 7,658,200(B2) discloses the use of a pressure regulation system for two chambers separated by a slit valve. The purpose is to monitor the differential pressure within the chambers to prevent unintentional opening of the chambers. This patent teaches the use of pressure sensors in each chamber, communicating with a control device, to prevent unintentional opening. These sensors are not used to monitor conditions that would affect the effectiveness of the seal.

[0024] U.S. Patent No. 6,575,186 describes the use of a series of sensors on a jointed slit valve door to control the speed of air pressure on the door surface in order to provide a gentler landing on the door during the closing process and avoid damage to the seal. Three sensors are used for positioning and interaction with the pneumatic closing system.

[0025] U.S. Patent No. 6,291,814 describes placing sensors with transmitters and receivers that monitor movement near the door at both ends of a slit valve to prevent the door from damaging the wafer as it moves on the seal plate.

[0026] U.S. Patent No. 5,363,872 describes control of a slit valve door based on differential pressure across a barrier (described as a wall) between an inlet chamber and a reaction chamber. Each chamber has a sensor that analyzes its differential pressure to control the operation of the door and the pressure applied by the slit valve door.

[0027] The applicant of this specification has contributed to the development of products for monitoring characteristics within reaction chambers and has previously developed a camera known as a “Wafer Cam” that enables camera sensing inside a processing chamber, but such a camera was not developed for operations to monitor the sealing performance of BSVs or other semiconductor valve assemblies.

[0028] Attempts to form conductive objects using quantum tunneling from needle-like particles and / or pressure-sensitive particles for quantum tunneling purposes, such as thin sheets of silicon-coated nickel graphite, composite structures useful as transducers having needle-like particles and dielectric particles in a liquid silicon polymer matrix that hardens to a solid, and pressure-sensitive conductive cloths, are described in U.S. Patents 6,646,540, 6,495,069, 7,301,435, 8,449,974, 8,765,027 and 9,546,859. Similarly, by the same inventors, U.S. Patent Application Publication 2018 / 0186965 describes polymer or elastomer binders such as polyurethane, natural rubber, polyvinyl acetate, polyvinyl chloride, acrylic polymers and silicones, including void-containing structures such as spiked nickel used in combination with spherical magnetite conductive materials in the aforementioned patents. The final material is described as being able to realize switching (electric field-assisted tunneling) and sensing (conductive tunneling), including as a force sensor, within a single device formed from thin films, sheets, filaments, filament coatings, 3D printing raw materials, and textile products.

[0029] The applicant previously co-developed a smart seal described in U.S. Patent Application Publication No. 2020-0378867(A1), which is based on the use of sensors placed at various locations on the BSV to read data related to microstress / microstrain, stress relaxation, microstrain measured against vacuum pressure acting on the door, temperature evaluated against the seal's cross-sectional shape, and the effect of temperature on microstrain, with the data being compared to calibrated baseline data to determine seal life in real time.

[0030] While such attempts to measure characteristics are very useful, there appears to be a preference in this field for simpler or more effective alternatives as indicators of seal life that do not require extensive sensor usage to provide the necessary data, especially when such sensors do not significantly affect the seal's ability to function and maintain consistent characteristics to the seal without the use of embedded microsensors or other sensor devices attached to the seal.

[0031] In this field, there is still a need for improved methods and critical analyses to ensure maximum useful seal life, which are easy to monitor and preferably do not affect the consistency of the seal's operation or properties, including maintaining good seal elastomer properties, mechanical properties, and chemical resistance properties. These methods and analyses are likely to help in selecting the optimal seals and associated maximum seal life for use in semiconductor processing, thereby minimizing downtime and uptime, improving maintenance cycles, and avoiding seal degradation failures.

[0032] In this field, there is a further need for seals suitable for use in semiconductor manufacturing processes and / or cleanroom environments that remain cleanroom-friendly, even when seal degradation occurs over time, by avoiding rough metal fillers, while simultaneously providing variable and / or highly responsive electrical properties. Furthermore, there is a need for such clean seals where controlled but varying levels of electrical properties are possible, as required for specific end applications such as electronic shielding or dissipation end applications, and where the conductivity level is consistent throughout the seal and can range from low to high levels. Such materials are particularly useful in semiconductor end applications where low levels of particulate matter and contamination are desired.

[0033] Gaskets and seals are available in the art for use in EMI shielding and / or RFI shielding for various end applications. For example, a shield can be inserted between an electromagnetic radiation source and a desired area of ​​protection. Shielding devices may include shielding gaskets or seals and can take various configurations to fill the gap between the EMI shielding device and the area to be protected. EMI shielding devices may include multilayers and / or coatings may be applied to various materials by sputtering conductive materials onto the surface of various materials using metals such as nickel or tin. Various matrix materials have been used in such parts and components, including metals and polymer or elastomer materials such as silicones, fluorosilicones, ethylene-propylene copolymers, epoxy polymers, and polyurethanes. Typically, fillers used in such materials are conductive in nature, generally contain metals or carbon, and are in the form of particle or fibrous fillers. For example, Russian Publication No. RU2724650C1 discloses the use of spherical particles of aluminum, graphite, or copper in silicones, fluorosilicones, or ethylene-propylene copolymers.

[0034] U.S. Patent Application Publication 2012 / 0177906(A1) teaches an EMI shielding composite material having a volume resistivity of 0.5 ohms-cm or less, comprising a metal filler dispersed in a thermoplastic matrix. The thermoplastics used include polyethylene, polyketone, and thermoplastic fluoropolymers (such as Teflon® FEP or polytetrafluoroethylene). The metal filler may be nickel particles or powder, silver-coated tin, or fibrous fillers such as stainless steel, bronze fibers, aluminum fibers, or nickel fibers. This patent describes a filler content of up to 70% by weight.

[0035] Conductive elastomers can also be used for EMI shielding. For example, U.S. Patent No. 9,814,164 discloses EMI shielding in a sealing system having a conductive elastomer such as conductive silicone rubber. This patent further describes the use of silicone rubber or fluorosilicone rubber compounded with embedded silver-plated aluminum particles, silver-plated glass beads, silver-plated copper particles, nickel-graphite particles, or conductive carbon.

[0036] U.S. Patent No. 8,633,402 describes EMI gaskets that may be formed from elastomer polymers such as elastomer polyethylene, polypropylene, polypropylene-EPDM blends, butadiene, styrene-butadiene, nitrile rubber, chlorosulfonate, neoprene, silicone, urethane, and fluorosilicone. The polymers may be filled with conductive particulate fillers such as carbon, graphite, copper, nickel, silver, and aluminum.

[0037] U.S. Patent No. 7,589,284 describes an EMI shielding material that may include an elastomer matrix such as silicone, urethane, or flexible epoxy; a non-conductive thermoplastic such as polystyrene, polycarbonate / acrylonitrile-butadiene-styrene alloy, polybutylene terephthalate, nylon, polycarbonate, or polyacrylonitrile-butadiene-styrene; or a conductive polymer such as polyaniline. The matrix material may include conductive fillers such as nickel-plated carbon powder, carbon powder, silver powder, copper powder, silver / copper powder, silver / aluminum powder, silver-plated glass spheres, or nickel powder.

[0038] U.S. Patent No. 9,635,790 describes a mesh sealing element which is a conductive sheet embedded in a matrix polymer gel, which may contain expanded metal.

[0039] U.S. Patent Application Publication No. 2003 / 0213939 describes a device filled with carbon nanotubes and with a pressure of 0.01 ohms-cm~10 8 This document describes thermoplastic or thermosetting elastomers, such as polyurethane, styrene-butadiene rubber, EPDM, and ethylene-propylene rubber, and others, having a volume resistivity of ohms-cm. Carbon nanotubes include vapor-grown nanotubes, which may be multi-walled or single-walled nanotubes. Carbon nanofibers may also be used. Carbon black and metal fillers such as metal-coated fibers may also be used.

[0040] The readily available shielding materials typically used in semiconductors or cleanrooms utilize silicon polymers with nickel-coated graphite particles. Despite the availability of various EMI and RFI composite materials, not all are satisfactory when used in cleanroom environments such as clean seals or semiconductor manufacturing processes. Such environments may require higher purity sealing materials (e.g., melt-workable fluoropolymers or perfluoropolymers, fluoroelastomers or perfluoroelastomers) or other polymers that do not introduce impurities into the manufacturing process. To achieve the desired electrical properties, the amount of conductive filler packed is often moderately high to achieve a uniform nominal EMI and / or RFI shielding effect, and very high to achieve high efficiency levels. For certain "clean" or highly chemical-resistant matrices, such high filler packing is impossible while maintaining adequate sealing and physical properties. Furthermore, in cleanroom environments, many state-of-the-art EMI and / or RFI filler materials, such as nickel-coated graphite or metallic fillers, can degrade over time, potentially becoming problematic particulate matter in the environment. With regard to some of the known EMI and / or RFI shielding materials in this field, maintaining consistent properties across the entire matrix material of the composition can still be difficult. As a result, the conductive properties within the matrix may also be inconsistent, potentially leading to excessive variability in performance and characteristics.

[0041] It would be beneficial to develop EMI and / or RFI shielding compositions for use in creating seals that achieve good sealing and physical properties, effective EMI and / or RFI shielding, and preferably minimize any influence of conductive materials in a clean environment when the underlying matrix deteriorates. Therefore, there is a need in this field to develop compositions that can achieve level-controlled electrical properties when required for a particular end-use, whether for forming the above-mentioned self-sensing materials having conductive and dissipative properties, or for realizing EMI and / or RFI shielding materials, or other conductive end-use products. Furthermore, there is a need in this field for such materials that generally have a consistent level of conductivity throughout the entire seal, gasket, or other shielding component, and whose conductivity range can be from low to high levels. Such materials can be particularly useful in semiconductor end-uses where low levels of particulate matter and contamination are desired. [Prior art documents] [Patent Documents]

[0042] [Patent Document 1] U.S. Patent Application Publication No. 2017 / 0130562(A1) [Patent Document 2] US Patent No. 7,841,582(B2) [Patent Document 3] U.S. Patent No. 8,815,616 [Patent Document 4] U.S. Patent No. 9,347,495 [Patent Document 5] U.S. Patent No. 8,282,013 [Patent Document 6] U.S. Patent No. 7,398,692 [Patent Document 7] U.S. Patent Application Publication No. 2018 / 0052104(A1) [Patent Document 8] U.S. Patent No. 9,975,758 [Patent Document 9] US Patent No. 7,658,200 (B2) [Patent Document 10] U.S. Patent No. 6,575,186 [Patent Document 11] U.S. Patent No. 6,291,814 [Patent Document 12] U.S. Patent No. 5,363,872 [Patent Document 13] U.S. Patent No. 6,646,540 [Patent Document 14] U.S. Patent No. 6,495,069 [Patent Document 15] U.S. Patent No. 7,301,435 [Patent Document 16] U.S. Patent No. 8,449,974 [Patent Document 17] U.S. Patent No. 8,765,027 [Patent Document 18] U.S. Patent No. 9,546,859 [Patent Document 19] U.S. Patent Application Publication No. 2018 / 0186965 [Patent Document 20] U.S. Patent Application Publication No. 2020-0378867(A1) [Patent Document 21] U.S. Patent Application Publication No. 2012 / 0177906(A1) [Patent Document 22] U.S. Patent No. 9,814,164 [Patent Document 23] U.S. Patent No. 8,633,402 [Patent Document 24] U.S. Patent No. 7,589,284 [Patent Document 25] U.S. Patent No. 9,635,790 [Patent Document 26] U.S. Patent Application Publication No. 2003 / 0213939 [Overview of the project] [Means for solving the problem]

[0043] Brief summary of the invention The present invention includes novel compositions and articles formed therefrom that can be used in a variety of end uses, including higher conductivity end uses for use in EMI shielding and / or RFI shielding, or lower conductivity end uses or dissipative end uses, the articles being capable of exhibiting conductivity as a thermoplastic or elastomer quantum tunneling composite (QTC) such that when subjected to compressive stress (such as under load), the articles exhibit higher conductivity than the conductivity of the articles when the compressive stress is released. In one embodiment, the novel compositions and articles formed therefrom may be insulating and then conductive when stress is applied. The measured change in conductivity with respect to an article when not subjected to compressive stress (whether initially insulating or conductive) and an article that is more conductive when subjected to compressive stress can be used to measure the lifespan over time of articles such as seals or gaskets. The compositions may also be dissipative in nature.

[0044] Various embodiments are disclosed herein in which the composition may be used to form articles suitable for use in end uses such as electromagnetic interference or radio frequency interference.

[0045] In one such embodiment, a composition for forming an article is disclosed, comprising at least one matrix polymer selected from the group consisting of at least one thermoplastic polymer and / or at least one curable polymer having at least one functional group for crosslinking; and a three-dimensional, branched and / or crosslinked carbon nanostructure additive supplied in such quantities that the article is conductive and has a volume resistivity level of about 0.5 ohms-cm or less after the article has been formed from the composition.

[0046] In embodiments herein, when formed on an article, the article is an electromagnetic interference shielding article and / or a radio frequency interference shielding article.

[0047] The at least one matrix polymer in this embodiment can be at least one curable polymer selected from the group consisting of a curable polymer containing at least one silicon-containing monomer, a curable polymer containing at least one monomer containing silicon and fluorine, a curable copolymer containing at least one acrylonitrile monomer and at least one butadiene monomer, a curable polymer containing at least one olefin monomer, a curable polymer containing at least one fluorinated monomer, a curable polymer containing at least one perfluorinated monomer, and blends and copolymers thereof. Upon curing, the cured polymer composition contains one or more elastomers selected from the group consisting of silicones, fluorosilicones, fluoroelastomers, perfluoropolyethers, perfluoroelastomers, and cured elastomers formed from blends and copolymers thereof. In one embodiment, the at least one curable polymer may be selected from the group consisting of curable fluorinated polymers and curable perfluorinated polymers. The at least one curable polymer can further be at least one curable perfluorinated polymer, or a blend or copolymer of at least one curable fluoropolymer and at least one curable perfluoropolymer.

[0048] In one embodiment, the matrix polymer is at least one curable polymer having at least one functional group for crosslinking, and the composition may further contain at least one crosslinking additive for reacting with at least one functional group for crosslinking. Upon curing of the curable polymer composition, the resulting cured material can be used for electromagnetic interference shielding applications or radio frequency interference shielding applications.

[0049] In one embodiment herein, the carbon nanostructure additive has a carbon content greater than or equal to about 97% (≧) and about 0.135 g / cm³. 3 It has a bulk density of .

[0050] This composition may further contain at least one filler different from at least one carbon nanostructure additive.

[0051] In this embodiment, the composition may further include about 0.1 to about 300 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer, more preferably about 0.25 to about 250 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer, and most preferably about 0.5 to about 250 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. In further embodiments, the composition may include about 0.5 to about 80 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

[0052] In this embodiment, if at least one matrix polymer is selected from the group consisting of at least one curable fluoropolymer, at least one curable perfluoropolyether, and at least one curable perfluoropolymer, the composition may contain about 10 to about 80 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer, more preferably about 10 to about 50 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer, and most preferably about 20 to about 40 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

[0053] In further embodiments of the composition, the matrix polymer may be a thermoplastic polymer selected from the group consisting of polyarylene polymers, melt-processable thermoplastic fluoropolymers, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, chlorofluoropolymers, silicon-based polymers, as well as non-curable fluoropolymers and perfluoropolymers, polyolefins, polyethylene terephthalate, polysiloxanes, polyurethanes, polyaramids, polyamides, polyimides, polyetherimides, polyphenylene sulfide, polyphenylene sulfone, polyethersulfone, polyamideimides, polybenizmidizole, polycarbonates, polyacrylonitrile-butadiene-styrene, polybutadiene-styrene, polyepoxides, and similar materials, as well as blends, copolymers, alloys, and other combinations thereof.

[0054] The composition may further contain one or more conductive fillers, distinct from the carbon nanostructure additives, selected from the group consisting of powders, flakes, and fiber fillers, which include one or more of carbon, metal-plated glass, and metal-plated particles, wherein the particles include metals or polymers, nickel-coated graphite, graphene, graphite, carbon black, graphene derivatives, single-walled carbon nanotubes, multi-walled carbon nanotubes, gold, silver, nickel, copper, and combinations or mixtures thereof. In such embodiments, the composition may contain about 0.25 to about 100 parts by weight of one additional conductive filler, distinct from the carbon nanostructure additives, per 100 parts by weight of at least one matrix polymer.

[0055] The present invention further includes articles formed from the above compositions when formed from a matrix polymer. These articles may be selected from gaskets, seals, covers, and component parts for use in electromagnetic interference shielding devices or radio frequency interference devices.

[0056] The present invention also relates to a composition for electromagnetic interference shielding and / or radio frequency interference shielding, comprising a thermoplastic polymer and / or at least one matrix polymer selected from at least one curable fluoropolymer, at least one curable perfluoropolyether, at least one perfluoropolymer, at least one curable polymer comprising silicon and fluorine, and a curable polymer having at least one functional group for crosslinking selected from copolymers and blends thereof; and at least 5 to about 300 parts by weight of a carbon nanostructure additive per 100 parts by weight of at least one matrix polymer, wherein when the composition is cured and formed into an article, the article has a volume resistivity level of about 0.5 ohms-cm or less, and the carbon nanostructure additive is three-dimensional, branched and crosslinked.

[0057] In this embodiment of the composition for electromagnetic interference shielding and / or radio frequency interference shielding, at least one matrix polymer may be at least one curable perfluoropolymer, and the composition may contain about 10 to about 80 parts by weight of carbon nanostructure additives per 100 parts by weight of at least one curable polymer. Furthermore, in this embodiment, at least one carbon nanostructure additive has a carbon content of ≥ about 97% and about 0.135 g / cm³ 3 It can have a bulk density of [value].

[0058] The present invention relates to a composition comprising at least one matrix polymer selected from thermoplastic polymers and / or curable polymers having at least one functional group for crosslinking, further comprising a three-dimensional, branched and / or crosslinked carbon nanostructure additive supplied in an amount such that an article is formed from the composition and the article exhibits one or more of the dissipative effect and quantum tunneling composite effect. In this embodiment, the composition may contain about 1 to about 30 parts by weight, preferably about 15 parts by weight, of the carbon nanostructure additive per 100 parts by weight of the at least one matrix polymer.

[0059] When an article is formed from the composition of this embodiment, the article has a quantum tunneling effect, and the composition preferably contains at least about 2 parts by weight to about 30 parts by weight, preferably about 15 parts by weight, of carbon nanostructures per 100 parts by weight of at least one matrix polymer, preferably at least about 3 parts by weight of carbon nanostructure additives per 100 parts by weight of at least one matrix polymer, and most preferably at least about 4 parts by weight of carbon nanostructure additives per 100 parts by weight of at least one matrix polymer. In one embodiment, the composition contains about 4 parts by weight to about 20 parts by weight of carbon nanostructure additives per 100 parts by weight of at least one matrix polymer, preferably about 4 to about 15 parts by weight of carbon nanostructure additives per 100 parts by weight of at least one matrix polymer.

[0060] In this embodiment, the matrix polymer may be a thermoplastic polymer selected from the group consisting of polyarylene polymers, melt-processable thermoplastic fluoropolymers, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, chlorofluoropolymers, silicon-based polymers, as well as non-curable fluoropolymers and perfluoropolymers, polyolefins, polyethylene terephthalate, polysiloxanes, polyurethanes, polyaramids, polyamides, polyimides, polyetherimides, polyphenylene sulfide, polyphenylene sulfone, polyethersulfone, polyamideimides, polybenizumidizol, polycarbonates, polyacrylonitrile-butadiene-styrene, polybutadiene-styrene, polyepoxides, and similar materials, as well as blends, copolymers, alloys, and other combinations thereof.

[0061] The composition may further contain one or more conductive fillers, distinct from the carbon nanostructure additive, selected from the group consisting of powders, flakes, and fiber fillers, which include one or more of carbon, metal-plated glass, and metal-plated particles, wherein the particles include metals or polymers, nickel-coated graphite, graphene, graphite, carbon black, graphene derivatives, single-walled carbon nanotubes, multi-walled carbon nanotubes, gold, silver, nickel, copper, and combinations or mixtures thereof. In such embodiments, the composition contains about 0.25 to about 100 parts by weight of one additional conductive filler, distinct from the carbon nanostructure additive, per 100 parts by weight of at least one matrix polymer.

[0062] The present invention may further include articles formed from compositions according to this embodiment. These articles may be thermoplastic and / or elastomer quantum tunneling composite materials, and may be selected from the group consisting of seals, gaskets, or other components in sealing assemblies.

[0063] In one embodiment, the article is an insulator when not subjected to compressive stress, and conductive when subjected to compressive stress. In another embodiment, when the article is not subjected to compressive stress, it has a different conductivity level than when the article is subjected to compressive stress.

[0064] In further embodiments, the article may be an elastomer quantum tunneling composite material and a self-sensing article, in which case, when the article is in electrical communication with a circuit and a voltage is applied, when the article is in use and subjected to compressive stress, a change in the conductivity of the article is measured, and this change in conductivity is used to determine and evaluate the performance of the article in real time.

[0065] The present invention relates to a method for producing an article, comprising the steps of: preparing a composition comprising at least one matrix polymer selected from thermoplastic polymers and / or curable polymers having at least one functional group for crosslinking, and at least one three-dimensional, branched and / or crosslinked carbon nanostructure additive, wherein the at least one carbon nanostructure additive is present in an amount of at least 0.1 parts by weight to about 300 parts by weight per 100 parts by weight of the matrix polymer; and forming an article from the composition by thermoforming the composition, or by curing and thermoforming the composition, wherein the article can be used in at least one of electromagnetic shielding devices and radio frequency shielding devices.

[0066] In this method, the article preferably has a volume resistivity of about 0.5 ohms-cm or less. At least one matrix polymer can be a curable polymer, and the composition may further contain at least one crosslinking additive for reacting with at least one functional group for crosslinking. In this method, the article may be selected from seals, gaskets, covers, or component parts of electromagnetic interference shielding devices and / or radio frequency interference shielding devices.

[0067] The present invention also includes a method for producing an article, comprising the steps of: preparing a composition comprising at least one matrix polymer selected from thermoplastic polymers and / or curable polymers having at least one functional group for crosslinking, and at least one three-dimensional, branched and crosslinked carbon nanostructure additive, wherein the at least one carbon nanostructure additive is present in an amount of at least about 1 part by weight to about 30 parts by weight per 100 parts by weight of the at least one matrix polymer; and forming an article from the composition by thermoforming the composition, or by curing and thermoforming the composition, wherein the article exhibits at least one of dissipative effects or quantum tunneling effects.

[0068] In this method, the article can be a seal, a gasket, or another component in a sealing assembly. The matrix polymer can be a curable polymer, and the composition may contain at least one crosslinking additive for reacting with at least one functional group for crosslinking. The curable polymer can be selected from the group consisting of curable fluoropolymers, curable perfluoropolyethers and curable perfluoropolymers, as well as blends and copolymers thereof. In one embodiment, the article is an elastomer quantum tunnel composite material. In this embodiment, the article is an insulator when not subjected to compressive stress and conductive when subjected to compressive stress. In another embodiment, the article is conductive when not subjected to compressive stress and has a different conductivity level than when the article is subjected to compressive stress, and in one embodiment, the conductivity level of the article when subjected to compressive stress is higher than the conductivity level when the article is not subjected to compressive stress.

[0069] In another embodiment, the article is an elastomer quantum tunnel composite material and is a self-sensing article; when the article is in a state of electrical communication with a circuit and a voltage is applied, when the article is in use and subjected to compressive stress, a change in the conductivity of the article is measured, and the change in conductivity is used to determine and evaluate the performance of the article in real time.

[0070] The above summary and the following detailed description of preferred embodiments of the invention will be better understood when read in conjunction with the accompanying drawings. For illustrative purposes, preferred embodiments are now shown in the drawings. However, it should be understood that the invention is not limited to the exact arrangements and means shown. [Brief explanation of the drawing]

[0071] [Figure 1] Figure 1 is a three-dimensional graph showing the level of particleization over time for the sample tested in Example 1 of this specification.

[0072] [Figure 2] Figure 2 is a series of graphs showing the volume resistivity against compressibility applied to O-ring shaped samples 12-16 in Example 2 of this specification.

[0073] [Figure 3] Figure 3 shows a series of graphs representing the volume resistivity against the compressibility applied to samples 17-20 of Example 2.

[0074] [Figure 4] Figure 4 shows a series of graphs of the volume resistivity for button-shaped samples 12-20 of Example 2.

[0075] [Figure 5] Figure 5 is a schematic diagram of the circuit used to measure the resistance in Example 3.

[0076] [Figure 6]Figure 6 is a graph showing the relationship between conductivity and compressibility in Siemens / cm for samples 29-31 of Example 3.

[0077] [Figure 7] Figure 7 is a graph showing the relationship between conductivity and compressibility for samples 37-40 of Example 3.

[0078] [Figure 8] Figure 8 is a graphical representation of the integrated data obtained from Figures 6 and 7 for samples 29-31 and 37-40 of Example 3.

[0079] [Figure 9] Figure 9 shows an example of a circuit used in a four-point probe configuration for monitoring conductivity fluctuations in a seal fabricated according to the present invention. [Modes for carrying out the invention]

[0080] Detailed description of the invention In this specification, terms such as “inside” and “outside,” “upper” and “lower,” “proximal” and “distal,” “upper” and “lower,” and similar terms are used to help readers of this disclosure to better understand the invention in consideration of the drawings herein, but the intention to help readers is not in any way to limit them.

[0081] The applicants have developed compositions and methods for using certain types of carbon nanostructure additives in various amounts, which may be useful as additives in, for example, EMI shielding and / or RFI shielding applications, or in amounts that may enable the article to function as a quantum tunneling composite (QTC) or dissipative conductive polymer or elastomer for use in various end applications. When acting as a QTC, in one embodiment, for example, a seal or gasket can be made to correspond to a level of compression, which can be interpreted from the change in conductivity of the polymer or elastomer under compressive stress during use, allowing for real-time evaluation of the seal or gasket's lifespan.

[0082] Therefore, in sealing applications, seals can be manufactured that act as self-sensing seals, which can be used in a variety of end applications, in which case monitoring of seal life is important for effective and cost-effective sealing performance and maintenance. In semiconductor applications, such seals may be used in slit valve doors with seals, e.g., BSVs, pendulum valves and other chambers, or valve assemblies with seals such as flow isolation valves, and may also be used in gas and / or liquid applications in pharmaceutical cleanroom applications, downhole and other oilfield applications, and chemical applications where fluids are handled as seals or other molded articles. As used herein, “seal” is intended to include a general classification of seals and sealing components, including O-rings, gaskets, V-rings, inserts, sealing or shielding layers, and other similar products, and is not intended to be limited unless a specific type of seal is expressly indicated. “Artifact” is intended to include parts, components, devices and seals that are formed or used as part of a product, either by using the compositions disclosed herein alone or in combination with other existing compositions.

[0083] With respect to articles such as seals, if a seal is realized that can respond with high sensitivity to applied compressive stress (such as when under load) by its conductivity level, the seal can act as a pressure sensor, and the deterioration of the seal can be evaluated in its new state by the relationship between compressive stress and baseline conductivity with and without applied load, and as a result, the seal life and performance can be replaced before the seal is affected by repeated use and / or harsh conditions. Self-sensing seals, and the methods and systems herein for monitoring seal life, are particularly useful in valve assemblies for semiconductor manufacturing, including seals such as vacuum seals or KF type seals, and BSVs and other semiconductor seals, but they may also be used in similar valves used in fluid handling, and in other environments, in particular, where seal life is critical to operation, and where the seal is present under pressure, strain, and environmental or ambient operating conditions that cause seal deterioration. This is a particularly challenging problem in semiconductor manufacturing, with a particular focus on semiconductor seal assemblies such as BSVs, pendulum valves and isolation valves. It will be understood that the embodiments described herein may be used for use in other similar valve sealing assemblies and end uses based on this disclosure.

[0084] Examples of gate and slit valves including seals are known in the art, and articles made from the compositions and methods herein may be implemented using any of these designs. Examples of commercially available acceptable doors of this nature are commercially available from Greene, Tweed & Co. (Kulpsville, Pennsylvania, USA) and are also described, for example, in U.S. Patent Application Publication 2012 / 0100379(A1), which is incorporated by reference in the relevant section. Other BSVs and gate valves having bonded assemblies or other assemblies including known or developed seals may be used in the systems and methods herein.

[0085] Such gate and slit valves are generally formed from metal door materials (metal or metal alloy), with preferred materials including aluminum or stainless steel. Seals in such doors are preferably formed from elastomer materials or materials that exhibit elastomer properties under operating conditions. Typical materials used are silicon-based elastomers, including fluoroelastomers, perfluoroelastomers, and fluorosilicones. Furthermore, backup rings or seals may also be incorporated as backup protective seals for primary seals, such as those formed using fluoropolymers alone (e.g., polytetrafluoroethylene) or elastomers or materials exhibiting elastomer properties.

[0086] Such seals may be mechanically attached to the door in place, bonded, or molded using a variety of commercially available materials and door assemblies.

[0087] The carbon nanostructure additives used herein are preferably formed to have a three-dimensional branched structure, and are also preferably formed to be contained within interconnected structurally crosslinked carbon nanotubes to form a three-dimensional branched carbon structure network. Such materials are distinct from standard single-walled and multi-walled carbon nanotubes, as well as carbon allotropes such as plate-like carbon and fluorinated graphite. In preferred embodiments herein, the carbon content is about ≥97%, and the concentration is about 0.135 g / cm³. 3Such three-dimensional branched carbon nanostructure additives having a bulk density are used, but their properties can vary depending on the degree of linking and branching carried out in the manufacturing process. One suitable carbon nanostructure for use herein is commercially available in pellet form from Cabot Corporation as Athlos® carbon nanostructure. Other suitable materials are also commercially available from Cabot and / or may be fabricated or manufactured or commercially purchased. Descriptions of branched and linked carbon nanostructure materials, as well as methods for fabricating them, can be found in U.S. Patents 9,107,272, 9,111,658, 9,447,259 and 9,650,501, each of which is incorporated herein in the relevant parts with respect to disclosures of methods for fabricating and preparing branched and linked carbon nanostructures.

[0088] Due to the dielectric properties of certain curable polymer compositions and the resulting elastomeric properties upon curing, particularly those of fluoroelastomers and / or perfluoroelastomers, the effect of branched three-dimensional carbon nanostructure additives is only perceptible to strong conductivity levels when the polymer is heavily packed. However, for other applications, such as preparing pressure-sensitive materials, smaller amounts of such carbon nanostructure additives are indicated.

[0089] In addition to the self-sensing end uses and other uses of QTC compositions described above and elsewhere in this specification, if articles are formed using a greater amount of conductive nanostructure additives as herein, seal or sealing components, including gaskets, covers, and various other component parts having polymer or elastomer raw materials as herein, can be formed from such articles, resulting in a bulk resistivity of about 0.5 ohms-cm or less, thereby achieving a useful EMI and / or RFI shielding effect.

[0090] With regard to EMI and / or RFI shielding applications, the filler amount can vary depending on the curable polymer selected. With various polymers, the composition may contain about 0.1 to about 300 parts by weight of carbon nanostructures per 100 parts by weight of at least one polymer or curable polymer in the composition, preferably about 0.25 to about 250 parts by weight, more preferably about 0.5 to about 250 parts by weight, or about 0.5 to about 80 parts by weight of carbon nanostructure additives per 100 parts by weight of at least one polymer or curable polymer in the composition.

[0091] Preferably, in polymers such as curable perfluoropolymers and curable fluoropolymers, about 10 to about 50 parts by weight per 100 parts by weight of the polymer or curable polymer can be used to achieve a desirable level of shielding by absorbing or reflecting EMI and / or RFI. In the case of curable perfluoropolymers and other curable fluoropolymers, which may otherwise be more difficult to fill to a high degree, about 20 to about 40 parts by weight per 100 parts by weight of the curable polymer in the composition may be used.

[0092] In preferred embodiments, the amount of carbon nanostructure additive used may vary in an attempt to obtain the best shielding effect, while, where possible, maintaining effective elastomeric and / or mechanical properties of the formed article used in the end application of the shield, all of which will depend on the type of shield portion or the components to be fabricated. With this material, the desired level of maximum bulk resistivity for effective shielding is about 0.5 ohms-cm, although this may be modified for various end applications. With perfluoropolymers, for example, using between about 20 and about 40 parts per 100 parts of perfluoropolymer in the composition allows for a bulk resistivity of about 0.5 ohms-cm while maintaining the required balance of mechanical and elastomeric properties.

[0093] The use of such carbon nanostructure additives in curable polymers makes it possible to form elastomer articles according to the present invention that, once cured, can have various shapes and configurations, such as forming them into component parts like seals, gaskets, EMI or RFI shielding devices, or EMI or RFI filter seals or filter covers. Furthermore, shielding components formed from other polymer matrix materials using the carbon nanostructures of this specification are also within the scope of this disclosure.

[0094] When incorporating at least one carbon nanostructure additive according to this specification into a curable polymer or other polymer matrix for use in the development of QTC effects or dissipative conductive polymers or elastomers, the inventions herein instruct that the amount of carbon nanostructure additive used be reduced. For example, using about 1 to 30 parts by weight of carbon nanostructure additive per 100 parts by weight of curable polymer or polymer matrix polymer can achieve a level of conductivity lower than that required for shielding applications. Preferably, about 1 to 15 parts by weight of carbon nanostructure additive per 100 parts by weight of curable polymer, or the polymer in the polymer matrix is ​​used.

[0095] When using some lower conductivity materials, such as antistatic dissipative materials, which can be used in automotive, aerospace, oilfield, medical and pharmaceutical, or other end uses requiring conductive materials that can dissipate charge to avoid sparks or other problems, but can still withstand the environment in which a particular elastomer matrix is ​​indicated, even lower filler amounts of up to about 15 parts by weight of additive per 100 parts by weight of any base polymer are acceptable for this purpose.

[0096] When using a composition for a QTC effect, such as when the composition has the ability to cause charged particles to rise sharply like QTC when the formed article is under compression, a low level of at least about 2 parts by weight, more preferably at least about 3 parts by weight, and most preferably at least about 4 parts by weight to about 30 parts by weight or about 15 parts by weight per 100 parts by weight of polymer or curable polymer in the composition is indicated. In some embodiments, about 4 parts by weight to about 20 parts by weight, more preferably about 4 parts by weight to about 15 parts by weight per 100 parts by weight of curable polymer in the composition may be used.

[0097] To produce the QTC effect, carbon nanostructures that are three-dimensional, branched, and crosslinked, resulting in longer, interconnected tubes, create a more densely accessible QTC electron transfer option throughout the article. The elastomer used can be selected to act as a dielectric when there is no compressive stress, such as the load applied during use, so the QTC effect in such an elastomer can be achieved by the applied compressive stress without the need for the intervention of dielectric additives and / or without the need for needle-shaped carbon as described in prior art QTC composites. Depending on the degree of compressive stress applied, the polymer matrix or elastomer matrix in the cured article can realize a dielectric environment activated with the application of compressive stress to a compressible dielectric elastomer material, resulting in a measurable proportional conductivity level within the matrix, which allows for real-time measurement and quantification of the relationship between the compressive stress during use and the content of carbon nanostructure additives in the elastomer, and analysis to determine the seal life.

[0098] For example, when a finished molded article, such as an elastomer seal, is installed for use in electrical communication with a circuit having an applied voltage and known resistance, it is possible to measure the bulk resistivity or conductivity of the seal both before the application of compressive stress, such as from the applied load or from the compression of moving parts around the seal in the ground, and before the same properties are measured over time when a predetermined amount of carbon nanostructure additive in the elastomer is used. Using the obtained relationship, it is possible to analyze when the additive and elastomer matrix begin to degrade and when the resistivity and conductivity change. Then, using such measurements, the performance and lifespan of the seal in use can be monitored and it can be determined when replacement is necessary.

[0099] By providing such molded articles from the compositions herein, it is possible to fabricate seals, gaskets, or other seal assemblies or component parts, such as polymer or elastomer components, that are "self-sensing" in that their properties are measured and evaluated, allowing for real-time determination of seal life and performance during use without the need for external sensors, the embedding of sensors that affect properties such as sealing characteristics, or the installation and relationship of complex sensors around or near the seal on a door surface such as a BSV door or gate, or inside or in the surrounding environment of a reaction chamber. Furthermore, the carbon nanostructures herein contribute to more consistent conductive properties throughout the polymer or elastomer matrix of the formed article.

[0100] Further use of the compositions herein may be used to form articles having a QTC effect formed from polymers or elastomers for forming self-sensing articles such as seals, and for use in other known QTC material applications formed from prior art QTC composite materials, such as for use in medical devices such as blood pressure measurement bands for blood pressure monitors, and for use in pressure-sensitive clothing for audio or telephone devices for playing digital sound or video files, for transducers in downhole equipment in oilfield applications such as U.S. Patent No. 8,893,547, for sports training dummies with sensors used in boxing or fencing, for evaluating athletic training shoes, for touch sensors and prostheses based on robotics technology and smart seals, and for use in various medical and pharmaceutical applications, using a variety of polymers and elastomers.

[0101] In addition to the carbon nanostructure additives described herein, the curable polymer compositions include at least one curable polymer incorporated into the composition before curing. Furthermore, such compositions may also include, in some preferred embodiments herein, a crosslinking agent or curable substance capable of crosslinking the curable polymer to form an elastomer. Crosslinking may also be thermally induced or irradiated using techniques known or developed in the relevant art, including curing of various commercial products using curing systems that function with their functional crosslinkable groups, including those that may be directed by manufacturers of commercial curable polymers as described below.

[0102] In the case of polymer-based compositions or elastomer compositions formed using polymer compositions that become curable once cured, such polymers and elastomer compositions can provide polymer or elastomer articles that can be used in a variety of end uses, including seals, such as O-rings, gaskets, component parts, coatings, layers, etc.

[0103] Other additives used may vary depending on whether the selected polymer system is non-curable or curable. For example, various curable polymers, when cured as elastomers, have a variety of mechanical and elastomeric properties and can tolerate, or are best used with, a variety of additives, processing aids, fillers, pigments, etc. Such additions to polymer and elastomer compositions are generally known.

[0104] The carbon nanostructures described herein, whether as shielding additives, dissipation additives, or QTC additives, can be used to impart specific conductivity and resistance properties to polymer matrices or curable polymer matrices and / or cured elastomer matrices. Therefore, the additives used are preferably those that can either complement or enhance their effects, or that do not substantially affect the desired conductivity and resistance properties, and that do not excessively adversely affect the mechanical or elastomer properties of the resulting article for its intended end use.

[0105] The compositions herein may contain elastomer matrix materials or non-elastomer matrix materials. Preferably, in EMI and / or RFI shielding components, the matrix is ​​an elastomer, and more preferably, in embodiments, the matrix is ​​a fluoroelastomer, including elastomeric perfluoropolyethers, fluorosilicones, perfluoroelastomers, and blends of these materials and blends of one or more types of these materials. The QTC components may be either elastomers or non-elastomers, but when forming a special self-sensing seal formed from the QTC composition, the matrix is ​​also preferably an elastomer.

[0106] With regard to suitable curable polymers, such materials include those that can be crosslinked or cured by functional groups to form an elastomer matrix material. For example, useful elastomers include silicones, fluorosilicones, nitrile rubbers, olefin rubbers (such as ethylene-propylene-diene rubber or ethylene-propylene rubber), perfluoropolyether-based elastomers, fluoroelastomers including perfluoroelastomers, polyurethanes, and copolymers and blends thereof.

[0107] Such elastomers are formed from curable polymers, copolymers, and blends thereof, including those formed from monomers containing silicon and / or fluorine, curable polymers having at least one acrylonitrile monomer and at least one butadiene monomer, curable polymers having at least one olefin monomer, and curable polymers having at least one fluorinated monomer and / or perfluorinated monomer. Such materials can be copolymerized, blended, and / or functionalized to form curable polymers. Preferably, at least one monomer used to form at least one curable polymer has one or more functional groups for crosslinking. Crosslinking can be achieved chemically, by irradiation or the use of heat, and / or by chemical reaction with crosslinking sites on functional groups on monomers, by adding one or more crosslinkable compounds that can crosslink with various monomers to form crosslinked polymers.

[0108] As used herein, “curing” is intended to encompass any method by which a curable polymer is given an elastomeric structure, such as vulcanization, chemical crosslinking, thermal crosslinking, catalytic crosslinking, or radiation crosslinking. After curing, the curable polymer forms an elastomer. As used herein, “elastomer” (sometimes also referred to as rubber) is intended to mean a polymer material that has viscoelastic properties, deforms when stress is applied, but restores part of its original form after the stress is released.

[0109] As used herein, "compression set" refers to the tendency of an elastomer material to remain deformed and not return to its original shape after the deformable compressive load has been removed. The compression set value is expressed as a percentage of the original deflection from which the material cannot recover. For example, a compression set value of 0% indicates that the material will completely return to its original shape after the removal of the deformable compressive load. Conversely, a compression set value of 100% indicates that the material will not recover at all from the applied deformable compressive load. A compression set value of 30% means that 70% of the original deflection has been recovered. Higher compression set values ​​generally indicate a potential for seal leakage.

[0110] Other elastomer properties typically measured include elongation at break, tensile modulus, and other physical properties. The influence of the elastomer's thermal behavior and its curing system on these properties is also useful for evaluating elastomers for various end-use applications.

[0111] The terms “uncured” or “curable” refer to a curable polymer for use in the compositions herein that has not yet undergone any significant degree of crosslinking reaction to the extent that the material is not yet sufficiently cured for its intended end use.

[0112] The following provides further information on useful categories of polymers that can be used herein, including the polymers mentioned above as useful as matrix materials for QTC components or EMI and / or RFI shielding components.

[0113] The silicones used herein may be formed using silicon-containing polymers, which can be any of a variety of silicone homopolymers and silicone copolymers that can be cured to form silicone elastomers (also known as silicone rubbers). Silicones are generally polymers that incorporate at least silicon, oxygen, and hydrogen into their chemical structure. Curable silicon-containing polymers (silicones) that can be used to form silicone elastomers include polymers having a main chain classified by the standard rubber nomenclature definitions presented by ASTM International in ASTM D1418-17 as VMQ (silicone), PVMQ (phenylsilicone), and FVMQ (fluorosilicone). However, silicones not readily classified by ASTM D1418-17 may be used, provided they demonstrate useful manufacturing characteristics. Any of such silicones, fluorosilicones, or phenylsilicones may be used in the present invention.

[0114] Silicones used to form silicone rubber can be cured using a variety of curing systems, including catalytic curing systems, typically using platinum-based catalysts, condensation curing systems, peroxide curing systems, and oxime curing systems.

[0115] In platinum-catalyzed curing, crosslinks are formed by addition reactions using functional silicone polymers such as vinyl-functionalized silicones and hydride-functionalized silicones. Such reactions leave no by-products and are therefore a preferred route for curing in this field.

[0116] Condensation systems typically involve a crosslinkable substance that is activated in a certain manner. A common one-component system uses a functional silicone that, upon contact with water at room temperature, undergoes hydrolysis, causing the hydrolyzable groups (hydroxyl or silanol groups) to initiate a curing reaction. Once the hydrolysis reaction begins, it continues until curing occurs, which can be carried out at room temperature. The crosslinkable substance is included in condensation systems involving alkoxy, acetoxy, ester, enoxy, or oximesilanes, such as functional silanes having active oxygen-containing groups, e.g., methyltrimethoxysilane, methyltriacetoxysilane, and similar substances. Such substituents and / or functionalized groups can also be catalyzed, if desired, using organometallic catalysts such as tetraalkoxytitanates, chelated titanates, or tin catalysts (e.g., dibutyltin dilaurate and acetoxytin).

[0117] In two-component condensation, the crosslinkable substance and any catalyst are held in one container while the curable silicone polymer composition (if such a substance is absent) is held in separate containers. Curing is initiated when the substances in the two containers are mixed.

[0118] Other silicone curing systems for forming silicone elastomers include peroxide curing systems that can crosslink via reactive silicone moieties and form Si-R-Si links between silicone chains. Suitable commercially available silicones for use herein include NuSil® from Nusil Silicone Technology Co., which can be used in QTC or EMI and / or RF shielding applications, and PDMS-Sylgard® from Dow-Corning, which can be used in QTC end applications.

[0119] The silicone polymers that may be used herein include polysiloxanes, polyalkylsiloxanes, polydialkylsiloxanes, polyarylsiloxanes, polyaralkylsiloxanes, and blends, alloys, or copolymers of these materials, or blends, alloys, or copolymers with other curable polymers described herein. Furthermore, such silicon-containing polymers may have one or more hydrogens on silicon atoms in the main chain substituted by one or more groups, or one or more silicon-bonding groups, each of which may be further functionalized, further substituted, or used for crosslinking. Such substituents or functional groups may be branched and / or linear groups, including, but are not limited to, hydroxyl, alkyl, alkenyl, alkynyl, aryl, alkoxy, alkenoxy, alkynoxy, aryloxy, arylalkyl, arylalkoxy, arylalkenoxy, vinyl, carboxyl, carbonyl, halogen, heterocyclic, and fluorinated or perfluorinated groups.

[0120] The compositions comprising silicone-containing polymers as described herein may include curing agents such as hydrolyzable crosslinking agents, curing initiators, crosslinking agents, curing catalysts such as organic peroxides, and other curing system components known or developed in the art.

[0121] In addition to at least one carbon nanostructure additive in the compositions herein, other different additives and / or modifiers that can be used in curable silicone or fluorosilicone compositions include, but are not limited to, siloxane additives, ultra-high molecular weight siloxane additives, clarifying agents, processing aids, stabilizers, colorants (such as pigments and dyes), other fillers (non-conductive and / or dielectric carbon black, quartz, calcined silica, standard carbon nanotubes, glass fibers and coupling agents as needed, aramid fibers, olefin fibers, carbon fibers, U This includes UV absorbers, UV stabilizers, lubricants (such as waxes), fatty acids and other rheological additives, flame retardants, polyols, amides, fluoropolymers, fluorinated or perfluorinated polymer additives, nanosilica (i.e., nanosilicon dioxide) particles, polysiloxanes, antiblocking agents (such as silica and talc), fluorescent whitening agents, dispersants, wetting agents, phase solvents and any other suitable silicon-containing polymer additives and / or modifiers, provided that such additives are not selected or used in amounts that block, prevent, substantially affect, or interfere with the desired conductivity level for the intended end use. Other conductive additives may also be used for modified conductivity properties, which are further described below in this disclosure.

[0122] For QTC applications, for example, there is no instruction to use levels of potentially conductive or semiconducting materials that would affect the QTC effect in self-sensing articles. Furthermore, when silicone is used in shielding end applications, it is desirable to incorporate carbon nanostructure additives as herein at higher filler levels, but not in such large quantities that the filler excessively increases the bulk resistivity. Finally, in these and other end applications, the amount of filler is also commonly controlled to achieve the desired compressive stress and resistivity changes for its intended end application.

[0123] Preferred additives in silicon-containing polymer compositions or compositions herein are peroxide curing agents, typically blended in an amount of about 0.5 to about 5.5 parts per 100 parts of silicone polymer, or, in other systems, platinum catalysts in an amount of about 0.0005 to about 0.0015 parts per 100 parts of silicon-containing polymer. Other preferred additives include colorants and pigments, such as white (titanium dioxide), yellow (iron oxide or azo), blue (phthalocyanine GS or ultramarine), and / or green (phthalocyanine BS), which can vary but are typically included individually in amounts up to about 1.0 part per 100 parts of silicon-containing polymer, or in total in amounts up to about 1.5 parts per 100 parts of silicon-containing polymer.

[0124] When used in compositions containing carbon nanostructure additives, such additives other than any specific curing system are generally added as needed and may be included in amounts up to about 50% by weight in total, excluding the curing agent and carbon nanostructure additives, provided that they do not overload the polymer or interfere with or substantially affect the function of the intended end use.

[0125] Depending on the curing system used, the amount of the relevant curing agent may be adjusted to suit the system. Since such curing systems are known in the art, the same system may be used herein as described above. Preferred examples of silicones for use in the present invention include commercially available silicones such as those manufactured by Stockwell Elastomerics (Pennsylvania) and Primasil Silicones Ltd. (United Kingdom), which may be used together as recommended by their manufacturers.

[0126] Acrylonitrile-butadiene and its copolymers and variants, as well as nitrile rubbers such as olefinic rubbers (EPDM or EPR, etc.), are well known and commercially available for use in the present invention, along with other known or art-developed olefinic rubbers such as Nipol® grade produced by Zeon, Keltan® grade produced by ArlanXeo Performance Elastomers, and Vistalon® produced by ExxonMobil. Such compositions and their additives are well known for use in component parts. Such elastomers are particularly suitable for use in QTC compositions and components herein.

[0127] Curable fluoropolymers for use in either QTC or EMI and / or RFI shielding end applications are (C n Any suitable curable fluoropolymer, including curable perfluoropolymers and curable perfluoropolyethers (PFPE) or PFPE copolymers, having at least one monomer unit of F2nO, with varying fluorine content, in which case such fluoropolymers preferably include functional groups or reactive monomers along or attached to the curable polymer main chain.

[0128] In summary, such fluoropolymers provide materials that are generally useful in harsh environments, such as those encountered in the oilfield industry, petrochemical processing, semiconductor manufacturing, gas and food processing, life sciences, and other clean environments. The use of carbon nanostructures in clean materials enables low levels of particulate contamination into the environment and achieves excellent conductivity in the various end uses described herein, while still maintaining good processability even at higher filler concentrations of carbon nanostructure additives as described herein.

[0129] Regarding curable fluoropolymers that can be used, there are materials classified by the standard rubber nomenclature definitions presented by ASTM International in ASTM D1418-17. Standard FKM polymers conforming to such elastomer nomenclature typically have at least two monomers, one of which is fluorinated, and preferably all of these are fluorinated to some extent, having at least one curing site monomer for use in vulcanization. The at least two monomers preferably include vinylidene fluoride and hexafluoropropylene or similar fluorinated olefins, but may also include a variety of other monomers known or developed in the art. The fluoroelastomer composition may also include at least one curing agent that can undergo a crosslinking reaction with the functional groups in the curing site monomers of the fluoroelastomer. As described above, PFPE monomers and comonomers may also be used.

[0130] With respect to FKMs as used herein, such curable site monomers may include one curable site monomer that can be cured by a peroxide or other curing system. With respect to peroxide curing systems, such curable site monomers may have functional groups in the curable site functional group that include a halogenated substance such as Br or I. At least two of the monomers in the FKM may be hexafluoropropylene (HFP) and vinylidene fluoride (VF2), but other typical monomers may be used in addition to these two to form a variety of fluoropolymers known in the art, and the curable site monomers and curing systems can be diverse. Such systems are known in the art.

[0131] The curable fluoropolymer may be crosslinkable by irradiation, but preferably is crosslinkable (curable) by a curing system, in which case a curing agent is added that reacts with functional groups in the curing site monomer to form an elastomer material. If necessary, at least one of a second curing agent, co-curing agent, and / or curing accelerator may also be used. Depending on the desired final properties, the compositions herein may have a single curable fluoropolymer or a combination of at least two curable fluoropolymers and / or curable perfluoropolymers, for example, in the form of a polymer blend, grafted composition, or alloy, copolymer, etc., as further described below.

[0132] The curable fluoropolymers for the compositions herein may optionally include additional such polymers in the above-described blend-like compositions or grafted / copolymer compositions. Furthermore, the polymer backbone may contain various curable site monomers along the chain that yield one or more different functional groups for crosslinking, preferably one of which is curable by a peroxide curing system for use in the present invention herein. The composition may also include curing agents and co-curing agents, and / or accelerators, to assist the crosslinking reaction. Further curable sites and curing systems may be given to the same or different curable site monomers, such as curable sites that react with a bisphenyl-based curing system to produce crosslinking, for example, such curable sites having nitrogen-containing reactive groups, provided that peroxide-curable functional groups are also preferably present. Thus, although the disclosure herein discusses a variety of preferred curing agents (also referred to herein as crosslinking agents or curing agents), other curing agents capable of curing such alternative curable sites may also be used, in addition to the preferred organic peroxide-based curing agents and co-curing agents herein, when additional curable sites known in the art are used. Further descriptions of such curing systems are presented below.

[0133] One or more curable fluoropolymers may be present in such compositions. Such polymers are formed by polymerizing or copolymerizing one or more fluorinated monomers. Such polymers can be formed using various techniques known in the art (such as direct polymerization, emulsion polymerization and / or free radical-initiated polymerization, latex polymerization, etc.).

[0134] Curable fluoropolymers may be formed by polymerizing two or more monomers, preferably one of which is at least partially fluorinated, but fully fluorinated monomers may also be used. For example, HFP and VF2 are preferably combined with tetrafluoroethylene (TFE) or one or more perfluoroalkyl vinyl ethers (PAVE) or similar monomers, together with at least one monomer that is a curing site monomer that enables curing, i.e., at least one fluoropolymer curing site monomer. The fluoroelastomer compositions described herein may preferably include any suitable standard curable fluoroelastomer fluoropolymer (FKM) that can be cured to form a fluoroelastomer using the curing system described herein and one or more other curing agents. Examples of suitable curable FKM fluoropolymers include Solvay Solexis, Tecnoflon® PL958, Tecnoflon® PFR-LT, Tecnoflon® FOR 801HS available from SpA (Italy), Dyneon® FE5610 or FC2211 available from 3M, and other similar fluoropolymers that, when used in the compositions herein, can be cured by peroxide curing systems or bisphenyl systems. Other suppliers of such materials include, among others, Daikin Industries, Ltd. (Japan); 3M Corporation; Minnesota; Chemours Company, Delaware; and EIDuPont de Nemours & Company, Inc., Delaware. Such FKM polymers are not fully fluorinated in the polymer backbone.

[0135] In certain embodiments, such as end-uses including clean environments, at least one first curable fluoropolymer may be a curable perfluoropolymer useful for forming a perfluoroelastomer. The compositions herein may contain only one fluoropolymer or perfluoropolymer, or may contain two or more such fluoropolymers or perfluoropolymers in a composition forming either a single fluoroelastomer or a perfluoroelastomer, or if two or more are used, they may form a perfluoroelastomer blend composition or copolymer for curing. Furthermore, a curable fluoropolymer may be blended with a curable perfluoropolymer to produce a blended partially fluorinated fluoroelastomer.

[0136] As used in this application, "perfluoroelastomer" or "cured perfluoroelastomer" includes, unless otherwise specified, any cured elastomer material or composition formed by curing a curable perfluoropolymer, such as the preferred curable perfluoropolymer in the curable compositions described herein.

[0137] A “curable perfluoropolymer” (sometimes referred to in the art as “perfluoroelastomer,” or more appropriately as “perfluoroelastomer gum”) suitable for forming a perfluoroelastomer that has been used and cured is a substantially completely fluorinated polymer, preferably a polymer that is completely perfluorinated in its polymer backbone. Based on this disclosure, it is understood that some residual hydrogen may be present in some perfluoroelastomers within the crosslinks of those materials due to the use of hydrogen as part of functional crosslinking groups. Cured materials such as perfluoroelastomers are crosslinked polymer structures.

[0138] A curable perfluoropolymer used in a preferred perfluoroelastomer composition herein, which, upon curing, forms a cured perfluoroelastomer, is formed by polymerizing one or more perfluorinated monomers, one of which is preferably a perfluorinated curable site monomer having a curable functional group as specified above. The functional group may be a reactive group that does not have to be perfluorinated, or may contain one. Two or more curable fluoropolymers or perfluoropolymers, and preferably at least one optional curative (curing agent), may be preferably combined in a composition herein, and then cured to form the resulting crosslinked and cured fluoroelastomer composition, preferably a perfluoroelastomer composition, as described herein.

[0139] As used herein, a curable fluorine-containing elastomer composition may also be a curable perfluoropolymer composition, which is a blended and combined composition formed from two or more curable polymers, each of which is formed by polymerizing two or more perfluorinated monomers, each of which contains at least one perfluorinated curable site monomer having at least one functional group (curable site) capable of curing when perfluorinated. Such a curable perfluoropolymer material is also commonly referred to as FFKM in accordance with the American Standards for Testing and Technology (ASTM) standardized rubber definition, which is incorporated herein by reference in the relevant sections, and as described herein in ASTM standard D1418-17.

[0140] As described herein, the present invention includes curable fluorine-containing elastomer compositions, preferably curable perfluoroelastomer compositions and cured perfluoroelastomer compositions, and molded articles formed from such curable fluorine-containing elastomer compositions.

[0141] Such perfluoroelastomer compositions preferably comprise at least one, more preferably two or more curable perfluoropolymers, preferably perfluoro-copolymers, at least one of which has a high content of tetrafluoroethylene (TFE). Other suitable comonomers may include other ethylenically unsaturated fluoromonomers. The degree of TFE used in the perfluoropolymer can vary to suit different final properties. Each polymer may also preferably comprise one or more perfluoroalkyl vinyl ethers (PAVEs), which may comprise an alkyl or alkoxy group that is linear, linear or branched, and may comprise an ether linking group. Preferred PAVEs for use herein include, for example, perfluoromethyl vinyl ether (PMVE), perfluoroethyl vinyl ether (PEVE), perfluoropropyl vinyl ether (PPVE), perfluoromethoxy vinyl ether, and other similar compounds. Particularly preferred PAVEs are PMVE, PEVE, and PPVE, with PMVE being the most preferred, which provides excellent mechanical strength to the resulting article formed from the curing of the curable composition herein. PAVE can be used alone or in combination with the above-described PAVE types within a curable perfluoropolymer and in the final curable composition, insofar as its use is consistent with the present invention as described herein.

[0142] Preferred perfluoropolymers are copolymers of TFE, at least one PAVE, and at least one perfluorinated curing-site monomer incorporating a curing site or functional group that enables crosslinking of the curable polymer. The curing-site monomers can be of various types having the preferred curing sites specified herein. Preferred curing sites preferably have a nitrogen-containing group, but since additional curable fluoropolymers or perfluoropolymers may be supplied to the composition in addition to the first and / or second curable perfluoropolymers, other curing-site groups such as carboxyl groups, alkylcarbonyl groups, or halogenated groups having, for example, iodine or bromine, as well as other curing sites known in the art, may also be used.

[0143] The disclosure herein also provides for curing by radiation irradiation or the use of various curing agents (also referred to herein as crosslinking agents, curing agents), and when using other curing sites known in the art, other curing agents capable of curing such alternative curing sites may also be used. For example, peroxide curing systems based on organic peroxides and related peroxide co-curing agents may be used in conjunction with halogenated functional curing-site groups. In other embodiments, at least one of the perfluoropolymers includes a nitrogen-containing curing site.

[0144] Exemplary curing-site monomers are listed below and can be used in the curable fluoropolymers or curable perfluoropolymers described herein for use in curable compositions, and most of these have a PAVE-based structure and have reactive sites. The polymers can be various, but a preferred structure is the following structure (A): CF2=CFO(CF2CF(CF3)O) m (CF2) n -X 1 (A) (where m is an integer of 0 or 1 to 5, n is an integer of 1 to 5, and X 1 is a nitrogen-containing group such as nitrile or cyano) It has a carboxyl group, an alkoxycarbonyl group, or a halogenated terminal group. 1 It can be used as such.

[0145] Most preferably, the curing site monomer in any curable fluoropolymer or curable perfluoropolymer, or in a blend of two curable perfluoropolymers in one or both of a first and second such curable perfluoropolymer, is as described in (A) above (wherein m is 0 and n is 5). Curing site or functional group X as specified herein 1 For example, the nitrogen-containing group contains a reaction site for crosslinking when it reacts with a curing agent. Compounds according to formula (A) can be used alone or in various combinations as needed. From the viewpoint of crosslinking, the crosslinkable functional group is preferably a nitrogen-containing group, more preferably a nitrile group.

[0146] Further examples of curing site monomers according to formula (A) include the following formulas (1) to (17): CY2 = CY(CF2) n -X 2 (1) (In the formula, Y is either H or F, and n is an integer between 1 and approximately 8.) CF2 = CFCF2R f 2 -X 2 (2) (In the formula, R f 2 (-CF2) n -,-(OCF2) n - where n is an integer from 0 to approximately 5. CF2 = CFCF2(OCF(CF3)CF2) m (OCH2CF2CF2) n OCH2CF2-X 2 (3) (In the formula, m is an integer between 0 and approximately 5, and n is an integer between 0 and approximately 5.) CF2 = CFCF2(OCH2CF2CF2) m (OCF(CF3)CF2)n OCF(CF2)-X 2 (4) (In the formula, m is an integer between 0 and approximately 5, and n is an integer between 0 and approximately 5.) CF2 = CF(OCF2CF(CF3)) m O(CF2) n -X 2 (5) (In the formula, m is an integer between 0 and approximately 5, and n is an integer between 1 and approximately 8.) CF2 = CF(OCF2CF(CF3)) m -X 2 (6) (In the formula, m is an integer between 1 and approximately 5.) CF2 = CFOCF2(CF(CF3)OCF2) n CF(-X 2 )CF3(7) (In the formula, n is an integer between 1 and approximately 4.) CF2 = CFO(CF2) n OCF(CF3)-X 2 (8) (In the formula, n is an integer between 2 and approximately 5.) CF2 = CFO(CF2) n -(C6H4)-X 2 (9) (In the formula, n is an integer between 1 and approximately 6.) CF2 = CF(OCF2CF(CF3)) n OCF2CF(CF3)-X 2 (10) (In the formula, n is an integer between 1 and approximately 2.) CH2=CFCF2O(CF(CF3)CF2O) n CF(CF3)-X 2 (11) (In the formula, n is an integer between 0 and approximately 5.) CF2 = CFO(CF2CF(CF3)O) m (CF2) n =X 2 (12) (In the formula, m is an integer between 0 and approximately 4, and n is an integer between 1 and approximately 5.) CH2 = CFCF2OCF(CF3)OCF(CF3) - X2 (13) CH2=CFCF2OCH2CF2-X 2 (14) CF2 = CFO(CF2CF(CF3)O) m CF2CF(CF3)-X 2 (15) (In the formula, m is an integer greater than 0.) CF2 = CFOCF(CF3)CF2O(CF2) n -X 2 (16) (In the formula, n is an integer that is at least 1.) CF2 = CFOCF2OCF2CF(CF3))OCF2 - X 2 (17) (In the formula, X 2 These are nitrile (-CN), carboxyl (-COOH), and alkoxycarbonyl group (-COOR). 5 (In the formula, R 5 (This can be an alkyl group of 1 to about 10 carbon atoms, which may be fluorinated or perfluorinated), a halogen, or an alkylated halogen group (such as I or Br, CH2I, etc.) which can be a reaction site subunit of a monomer. When perfluorinated compounds are used as curing site monomers, they generally do not have hydrogen atoms in such portions of the main chain of the curing site monomer in the polymer main chain. Such curing site monomers are used when excellent heat resistance is desired for perfluoroelastomers resulting from the curing of perfluoropolymers and to prevent molecular weight reduction due to chain transfer during the synthesis of perfluoroelastomers by polymerization reactions. Furthermore, compounds having a CF2=CFO- structure are preferred because they provide excellent polymerization reactivity with TFE.

[0147] Suitable curing site monomers may include those having nitrogen-containing curing sites, such as nitrile or cyano-curing sites, for preferred crosslinking reactivity. However, curing sites (having multiple different main chains in addition to those mentioned above), as well as curing sites having carboxyl, alkoxycarbonyl, COOH, and other similar curing sites known in the art and to be developed, may also be used. Curing site monomers may be used alone or in various combinations.

[0148] Perfluoropolymers that may be used herein contain TFE in a molar percentage of about 50 to about 95 mol% or about 40 to about 80% of TFE in the perfluoropolymer compound, depending on the desired properties. Such perfluoropolymers may also incorporate further perfluorinated comonomers, such as PAVE, many of which are known in the art and may be used herein. Various PAVEs may be used in curable polymers for use in the compositions herein. The curing site monomer may also be a perfluorinated curing site monomer having, in one embodiment, a further curing site monomer, which may be a cyano group. In one embodiment, there may be two such curing site groups, such as one curing site having a primary cyano curing site group and one curing site having an auxiliary cyano curing site group.

[0149] Suitable perfluoropolymers are commercially available from Daikin Industries, Ltd. and described in U.S. Patent Nos. 6,518,366 and 6,878,778 and U.S. Published Patent Application No. 2008-0287627, which are each incorporated herein by reference in the relevant portions relating to perfluoropolymers. Further commercially available perfluoropolymers for use in the preferred embodiments herein, comprising at least two curing site monomers, are those available from Federal State Unitary Enterprise SVLebedev Institute of Synthetic Rubber of Petersburg (Russia) and Lodestar (the United States), as described in the scope of International Publication No. WO00 / 29479(A1), which is incorporated herein by reference in the relevant portions relating to perfluoroelastomers, and commercially available perfluoroelastomers available from Federal State Unitary Enterprise SVLebedev Institute of Synthetic Rubber as PFK-65, PFK-100, PFK-200, PFK-300, and other similar polymers. Suitable perfluoropolymers are also available from Dyneon as PFE 300Z, PFE 133TB, or PFE8IT, depending on the desired final properties.

[0150] In some embodiments of this specification, a curable perfluoropolymer having a TFE content in the range of about 40 to about 80 mol% and a PAVE content in the range of about 20 to about 60 may be used, and each of the curable site monomers may be present in an amount of about 0.1 mol% to about 10 mol% in total, or each may be present in an amount of about 0.1 to about 6 mol%. In another embodiment, the first curable site monomer may be present in an amount of about 0.2 to about 2.0 mol%, and the second curable site monomer may be present in an amount of about 0.5 to about 5.0 mol%.

[0151] In some embodiments, two or more curable fluoropolymers may be used in the blend, in which case the polymers such as those described above may be used together with a second curable fluoropolymer or curable perfluoropolymer used herein, which may be the same as or different from those described above, and such second curable polymer may, but is not required to, have the same content as TFE or PAVE. Preferably, a second perfluoropolymer or fluoropolymer may be used, which may contain a fluoroplastic material such as a fluoroplastic. Fluoroplastic particles can be obtained in various forms and using various techniques. Each of fluoroplastics such as PTFE in various sizes (microparticles, nanoparticles, etc.), and their copolymers (FEP and PFA type polymers), core-shell, or other modified fluoropolymers may be compounded into the material by mechanical means or by chemical processing and / or polymerization, either alone or in combination. Known or developed techniques may be used, such as those described in U.S. Patent Nos. 4,713,418 and 7,476,711 (each of which is incorporated herein by reference with respect to such techniques), and other techniques described in U.S. Patent No. 7,019,083, which is also incorporated herein by reference with respect to the use of fluoroplastic particles. Suitable commercially available polymers are available from 3M Corporation (St. Paul, Minnesota).

[0152] Examples of resulting elastomers formed using other perfluoropolymers and curing site monomers such as those described above can also be found in U.S. Patent Nos. 6,518,366, 6,878,778, and U.S. Published Patent Application No. 2008-0287627, and U.S. Patent No. 7,019,083, each incorporated herein in the relevant portions of the perfluoropolymers and resulting elastomers and methods for forming them described herein.

[0153] Perfluoropolymers for use in the compositions claimed herein can be synthesized using any known or developed polymerization techniques for forming fluorine-containing elastomers, including, for example, emulsion polymerization, latex polymerization, chain-initiated polymerization, batch polymerization, etc. Preferably, polymerization is carried out such that the reactive curing sites are located at one or both ends of the polymer backbone and / or suspended from the main polymer backbone.

[0154] Uncured (curable) perfluoropolymers are commercially available, including perfluoropolymers marketed under the names Dyneon® by 3M Corporation (St. Paul, Minnesota), Daiel-Perfluor® by Daikin Industries, Ltd. (Osaka, Japan), and other similar polymers. Other preferred materials are also available from Solvay Solexis (Italy), Federal State Unitary Enterprise SVLebedev Institute of Synthetic Rubber of Petersburg (Russia), Asahi Glass (Japan), and WLGore. Further examples of preferred perfluoropolymers and their blends can be found, for example, in U.S. Patents 9,018,309 and 9,365,712, which are incorporated herein by reference with respect to preferred perfluoropolymers and their blends.

[0155] Uncured perfluoropolymers can be cured by any method, including the use of radiation curing, but preferably contain at least one curing agent (also referred herein as a crosslinking agent, curing agent and / or curing system) for use with various curable fluorine-containing elastomers, and the perfluoroelastomer compositions herein may be selected for use with various curing sites described herein, and should be curable (i.e., reactable and crosslinkable) or otherwise capable of curing with the curing sites or functional groups of various uncured perfluoropolymer curing site monomers in the composition to form crosslinks, thereby obtaining elastomer materials in the form of molded articles.

[0156] Preferred crosslinking agents or curing agents are those that form crosslinks having oxazole, thiazole, imidazole, or triazine rings. Such compounds, as well as other curing agents including amidooximes, tetraamines, and amidorazones, may be used for crosslinking in the present invention.

[0157] For nitrogen-containing curing sites, preferred curing agents are bisphenyl-based curing agents and their derivatives, including bisaminophenol and its salts, and combinations thereof. Bisaminothiophenol, parabenzoquinone dioxime (PBQD), and salts of various such compounds may be used. Examples of preferred curing agents can be found, for example, in U.S. Patents 7,521,510(B2), 7,247,749(B2), and 7,514,506(B2), each of which is incorporated herein in the relevant section with respect to a listing of various curing agents for cyano-containing perfluoropolymers. Furthermore, perfluoropolymers may be cured using radiation-curing techniques.

[0158] A more preferred curing agent for curing sites having cyano group curing sites is a curing agent having an aromatic amine having at least two crosslinkable groups as shown in the following formulas (I) and (II), or a combination thereof, which form a benzimidazole crosslinked structure upon curing. These curing agents are known in the art and are discussed in the relevant parts and with specific examples in U.S. Patents 6,878,778 and U.S. Patent 6,855,774, which are incorporated herein by reference. [ka] (In the formula, R 1 In each group according to formula (II), these are the same or different, NH2, NHR 2 , OH, SH, or a monovalent organic group or other organic group having about 1 to about 10 carbon atoms, such as alkyl, alkoxy, aryl, aryloxy, aralkyl and aralkyloxy, where the nonaryl type group may be branched or linear, substituted or unsubstituted, R 2 The group may be -NH2, -OH, -SH, or an aliphatic hydrocarbon group, a phenyl group, or a benzyl group, or a monovalent or other organic group such as an alkyl, alkoxy, aryl, aryloxy, aralkyl, or aralkyloxy group, each having about 1 to about 10 carbon atoms, and non-aryl type groups may be branched or linear, and may be substituted or unsubstituted. Preferred monovalent organic groups, such as alkyl and alkoxy (or their perfluorinated forms), or other organic groups, have 1 to 6 carbon atoms, and preferred aryl-type groups are phenyl and benzyl groups. Examples include -CF3, -C2F5, -CH2F, -CH2CF3 or -CH2C2F5, phenyl group, benzyl group; or phenyl or benzyl group, where 1 to about 5 hydrogen atoms are substituted with fluorine atoms, such as -C6F5, -CH2C6F5, and the group may be further substituted with -CF3 or other lower perfluoroalkyl groups, or phenyl or benzyl groups, where 1 to 5 hydrogen atoms are, for example, C6H5-n (CF3) n -CH2C6H 5-n (CF3) n The group is substituted with CF3 (where n is approximately 1 to 5). The hydrogen atoms may be further substituted with phenyl or benzyl groups. However, phenyl and CH3 groups are preferred because they result in excellent heat resistance, good crosslinking reactivity, and relatively easy synthesis.

[0159] A structure having formula (I) or (II) incorporated into an organic amine should contain at least two such groups of formula (I) or (II), thus yielding at least two bridging reactive groups.

[0160] Similarly, curing agents having the following formulas (III), (IV), and (V) are useful in this specification. [ka] (In the formula, R 3 Preferably, it is an organic group such as SO, O or CO, or an alkyl, alkoxy, aryl, aralkyl or aralkoxy group having 1 to 6 carbon atoms, or an alkylene group, or a perfluorinated form of such a group having about 1 to about 10 carbon atoms, and is branched or linear, saturated or unsaturated, branched or linear (with respect to non-aryl type groups), or single bond, R 4 Preferably, the reactive side group is, for example: [ka] (This is shown in [the document]) [ka] (In the formula, R f 1 (i) is a perfluoroalkyl group or perfluoroalkoxy group of about 1 to about 10 carbon atoms, which may be a linear or branched group and / or saturated or unsaturated and / or substituted or unsubstituted); and [ka] (n is an integer between approximately 1 and approximately 10).

[0161] A single curing agent or a combination thereof may be selected from all curing agents specified herein within the scope of the present invention, depending on the curing site to be crosslinked. With respect to heat resistance, oxazole, imidazole, thiazole, and triazine ring-forming crosslinking agents are preferred and may include compounds of the formulas listed below with respect to formulas (I), (II), (III), (IV), and (V), which are discussed further below, specifically formula (II) (wherein R 1 They are either the same or different, and are -NH2 and -NHR respectively. 2 , -OH or -SH, R 2 is a monovalent organic group, preferably not hydrogen); formula (III) (wherein R 3 R is -SO2-, -O-, -CO-, and alkylene groups of 1 to about 6 carbon atoms, perfluoroalkylene groups of 1 to about 10 carbon atoms, or single bonds. 4 This is as stated below; Equation (IV)(R f 1 R is a perfluoroalkylene group with 1 to about 10 carbon atoms, and the formula is (V) (wherein n is an integer from 1 to about 10). Among such compounds, the one of formula (II) as specified herein is preferred with respect to heat resistance, and the heat resistance is enhanced by the stabilization of the aromatic ring after crosslinking. 1 Regarding NR, 2 Join (R 2 (It is a monovalent organic group, not hydrogen) has higher oxidation resistance than the NH bond, so R 1 as - NHR 2 It is still preferable to use it.

[0162] A compound having at least two groups as shown in formula (II), with two to three crosslinkable reactive groups thereon, and more preferably two crosslinkable groups, is preferred.

[0163] A preferred exemplary curing agent based on the above formula includes at least two functional groups, such as structural formulas (VI), (VII), or (VIII): [ka] (In the formula, R 5 This represents saturated or unsaturated, branched or linear, substituted or unsubstituted groups, such as alkyl, alkoxy, aryl, SO, O, CO, or similar groups that are perfluorinated with respect to carbon atoms, preferably having about 1 to about 10 carbon atoms. [ka] (In the formula, R 1 This is as defined elsewhere in this specification, and R 6 (The group is O, SO2, CO, or an organic group that may be perfluorinated, such as an alkyl, alkoxy, aryl, aryloxy, aralkyl, or aralkyloxy group having about 1 to about 10 carbon atoms, and the non-aryl type group may be branched or linear, substituted or unsubstituted, or have a single bond or alkylene bond).

[0164] From the viewpoint of easy synthesis, in further embodiments preferred herein, the most preferred crosslinking agent is a compound having two crosslinkable reactive groups represented by formula (II), which is shown in the following formula (VIII). [ka] (In the formula, R 1 As stated above, R 6 This is -SO2, -O-, -CO-, an alkylene group with 1 to about 6 carbon atoms, a perfluoroalkylene group with 1 to about 10 carbon atoms, a single bond, or a group shown in formula (IX): [ka] (In this formula, this formula facilitates easier synthesis). Preferred examples of alkylene groups with 1 to about 6 carbon atoms include methylene, ethylene, propylene, butylene, pentylene, and hexylene. Examples of perfluoroalkylene groups with 1 to about 10 carbon atoms include: [ka] These are examples of bisaminophenyl compounds. Preferred compounds with this structure include those of formula (X): [ka] (In the formula, R 7 In each case, they are the same or different, R 7 Each of these is a hydrogen atom, an alkyl group with 1 to about 10 carbon atoms, a partially fluorinated or perfluorinated alkyl group with 1 to about 10 carbon atoms, a phenyl group, a benzyl group, or a phenyl or benzyl group (where 1 to about 5 hydrogen atoms are replaced by fluorine or a lower alkyl group or perfluoroalkyl group (such as CF3)).

[0165] Non-limiting examples of curing agents include 2,2-bis(2,4-diaminophenylhexafluoropropane), 2,2-bis[3-amino-4-(N-methylamino)phenyl]hexafluoropropane, 2,2-bis[3-amino-4-(N-ethylamino)phenyl]hexafluoropropane, 2,2-bis[3-amino-4-(N-propylamino)phenyl]hexafluoropropane, 2,2-bis[3-amino-4-(N-phenylamino)phenyl]hexafluoropropane, 2,2-bis[3-amino-4-(N-perfluorophenylamino)phenyl]hexafluoropropane, 2,2-bis[3-amino-4(N-benzylamino)phenyl]hexafluoropropane, and similar compounds. Among these, preferred excellent resistance For thermal properties, 2,2-bis[3-amino-4(N-methylamino)phenyl]hexafluoropropane, 2,2-bis[3-amino-4-(N-ethylamino)phenyl]hexafluoropropane, 2,2-bis[3-amino-4-(N-propylamino)phenyl]hexafluoropropane, and 2,2-bis[3-amino-4-(N-phenylamino)phenyl]hexafluoropropane are preferred. Similarly, for heat resistance, tetraamines such as 4,4'-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[N1-phenyl-1,2-benzenediamine] or 2,2-bis[3-amino-4-(N-phenylaminophenyl)]hexafluoropropane are preferred.

[0166] Other suitable curing agents include oxazole, imidazole, thiazole, and triazine ring-forming curing agents, amidooxime and amidorazone crosslinking agents known or developed in the art, and in particular bisaminophenol, bisaminophenol AF and combinations thereof; bisaminothiophenol; bisamidine; bisamidooxime; bisamidorazone; monoamidine; monoamidooxime and monoamidorazone, examples of which, including curing agents and co-curing agents, as well as accelerators in them, are incorporated herein by reference in the relevant portions, for example, described in U.S. Patents No. 7,247,749 and No. 7,521,510. The bisamidooxime, bisamidorazone, bisaminophenol, bisaminothiophenol, or bisdiaminophenyl curing agents are most preferred herein because, in some embodiments herein, they react with nitrile groups, i.e., cyano groups, carboxyl groups, and / or alkoxycarbonyl groups in the perfluoropolymer to form preferred perfluoroelastomers having oxazole rings, thiazole rings, imidazole rings, or triazine rings as crosslinks in the cured articles formed from the compositions herein.

[0167] In one embodiment described herein, a compound comprising at least two crosslinking reactive groups, such as those in formula (I) or (II), may be used to improve heat resistance and stabilize the aromatic ring system. In the case of groups such as those in (I) or (II) having two or three such groups, it is preferable to have at least two such groups in each group (I) or (II), as having fewer groups may not result in proper crosslinking. Such combinations are known and are described in the applicant's U.S. Patents 9,018,309(B2) and 9,365,712(B2), which are incorporated herein by reference in the relevant portions.

[0168] Such compositions are blends having a first curable perfluoropolymer and a second curable perfluoropolymer, preferably in a ratio ranging from about 95:5 to about 5:95, preferably about 80:20 to about 20:80, and more preferably about 40:60 to about 60:40 or about 50:50. Each of at least one curable site monomer in each curable perfluoropolymer is preferably present in each of the curable perfluoropolymers used in any blend composition, in an amount of about 0.1 to about 10 mol% each and individually.

[0169] If at least one curing agent is used, this curing agent may be present in a variety of amounts suitable for curing the curing site monomers of the curable perfluoropolymer in the composition, for example, in a total amount of about 0.2 parts by weight to about 10 parts by weight per 100 parts by weight of at least one curable perfluoropolymer, each of which may be present in the composition in an amount of about 0.1 to about 6 parts by weight per 100 parts by weight of perfluoropolymer, or preferably in an amount of about 0.1 to about 2 parts by weight per 100 parts by weight of perfluoropolymer. In one embodiment, at least two curing agents are used, in the case of a first curing agent, in an amount of about 0.5 to about 4 parts by weight per 100 parts by weight of perfluoropolymer in the first perfluoropolymer, and in the case of at least one second curing agent, in an amount of about 0.3 to about 2 parts by weight per 100 parts by weight of perfluoropolymer.

[0170] The curing site in one or both of the curable perfluoropolymers in the blend may be a nitrogen-containing curing site in one of the curable site monomers. The curing site in the first curable perfluoropolymer may be selected from the group consisting of cyano, carboxyl, carbonyl, alkoxycarbonyl, and combinations thereof, and is most preferably a cyano group.

[0171] At least one curing agent is preferably one of the following suitable curing agents: fluorinated imidoyl amidine; bisaminophenol; bisamidine; bisamidoxime; bisamidrazone; monoamidine; monoamidoxime; monoamidrazone; bisaminothiophenol; bisdiaminophenyl; tetra-amine, and formula (II):

Chemical formula

Chemical formula

Chemical formula

Chemical formula

Chemical formula

[0172] At least one curing agent is more preferably an aromatic amine (R) having at least two crosslinkable groups represented by formula (II). 1 -NHR 2 Fluorinated imidoylamidines; bisaminophenols; and combinations thereof.

[0173] In one embodiment, the curable fluorine-containing elastomer composition comprises at least one curing agent, which is preferably a tetraamine compound within the range of such compounds described above. Such compounds may be used alone or in combination. The most preferred compound for use herein as a curing agent is that which is given by formula (II) (wherein R 1 -NHR 2 And R 2 ( is an aryl group). Such compounds are also known as 4,4'-[2,2,2-trifluoro-1-(trifluoromethyl)ethylidene]bis[N1-phenyl-1,2-benzenediamine] ("Nph-AF") (also known as "V6"). [ka]

[0174] In other embodiments herein, the curing agents that can be used include perfluoroimidoylamidines, such as those found in U.S. Patent No. 8,362,167, which are incorporated by reference in the relevant parts herein with respect to the following compounds and similar compounds. One preferred compound, also described as DPIA-65, is shown below.

Chem.

[0175] In one embodiment, the composition may be a perfluoroelastomer composition, and at least one curing agent is the use of Nph-AF (or V6):

Chem.

Chem.

[0176] In other preferred embodiments herein, the compound of formula (XII) is used alone or

Chem.

Chem.

Chem.

[0177] In another embodiment, the preferred ratio of the curing agent type represented by formula XII to the bisaminophenol type curing agent or related compound can be preferably about 0.5:1 to about 35:1, preferably about 1:1 to about 32:1, and most preferably about 2:1 to 15:1.

[0178] One curable perfluoroelastomer composition for use with the carbon nanostructures described herein comprises a curable perfluoropolymer containing tetrafluoroethylene, a first perfluoroalkyl vinyl ether, and at least one first curable site monomer having at least one curable site, or in a further embodiment, at least two curable site monomers, wherein the tetrafluoroethylene and the second perfluoroalkyl vinyl ether are present in varying amounts in the curable perfluoropolymer. At least one second curable site monomer having at least one curable site may also be used. Additional curable perfluoropolymers may also be used.

[0179] The carbon nanostructure additives used herein may be incorporated into the polymer blend before or after blending the polymer, and before or after incorporating any other fillers or additives; however, if a blended polymer is used, it is preferable that the polymer be blended before introducing the additives or fillers and / or the carbon nanostructure additives herein. Any curing agent is also preferable to be introduced after other fillers and additives, including the carbon nanostructure additives, and before curing to avoid premature curing.

[0180] Curing nitrile groups using curing agents specified herein for use with fluorine-containing curable perfluoropolymers having nitrile groups, etc., as well as curing agents known in the art for at least one curable perfluoropolymer and / or other perfluoropolymers added to the compositions herein, is within the scope of the present invention. Examples of other preferred curing agents known in the art include those capable of forming triazine rings. When using halogenated curing sites, peroxide curing agents and co-curing agents known in the art may also be used. Other suitable curing agents may include those listed above.

[0181] Although not necessary, additives other than the curing agents and carbon nanostructure additives herein that may be incorporated into curable fluoropolymers and perfluoropolymer compositions, blends and copolymers include, particularly for EMI / RFI applications not in the environment, one or more curing accelerators, co-curing agents, co-agents, processing aids, plasticizers, fillers (such as silica) (as long as it does not affect the conductivity), the above fluoropolymers such as TFE, fluorinated copolymers, core-shell modified fluoropolymers, etc. (in the form of micropowders, pellets, fibers and nanopowders), fluorographite (in an amount that does not affect the desired final effect or conductivity effect), barium sulfate, non-conductive carbon black, low-conductive carbon black or dielectric carbon black, or fluorocarbons, clay, talc, metal fillers (such as titanium oxide, aluminum oxide, yttrium oxide, silicon oxide, zirconium oxide, etc.), metallic substances are problematic metal carbides (such as silicon carbide, aluminum carbide), metal nitrides (such as silicon nitride, aluminum nitride), other inorganic fillers (such as aluminum fluoride, fluorocarbon), colorants, organic dyes and / or pigments (such as azo, isoindolenone, quinacridone, diketopyrrolopyrrole, anthraquinone, etc.), imide fillers (such as polyimide, polyamide-imide and polyetherimide, etc.), ketone plastics (such as polyarylene ketones such as PEEK, PEK and PEKK), polyarylate, polysulfone, polyethersulfone, polyphenylene sulfide, polyoxybenzoate, etc. can be used in amounts known in the art, and / or may vary for various properties. All fillers herein may be used alone or in combination with two or more such fillers and additives.

[0182] Preferably, any additives within the range of at least one optional curing agent capable of curing the curing sites on one or more curing site monomers, including any curing accelerators, co-curing agents, co-agents, etc., are added after other fillers, additives and / or carbon nanostructure additives, such as pellets, are incorporated into the fluoropolymer or perfluoropolymer, mixed or blended, and their network is formed within the curable polymer during the mixing or blending.

[0183] Compositions for end-use and molded articles, particularly for use in EMI and RFI shielding, can, if desired, be filled with a large amount of carbon nanostructure additives. Optional fillers such as those described above may be used in the composition in a total amount of up to about 100 parts, or even up to 300 parts, per 100 parts of at least one curable polymer, more or less as further described below.

[0184] After the curable polymer is combined with the carbon nanostructure additive and / or any other optional additives including any optional curing agent and related additives (if present), the curable polymer in the fluoroelastomer composition or perfluoroelastomer composition is cured to form the cured fluoroelastomer article or perfluoroelastomer article described herein.

[0185] The curable composition is preferably cured at a temperature and time traditionally used to form the desired crosslinks, depending on the selected curing method or curing system, curing site and / or curing agent. The temperature should be sufficient to allow the curing reaction to proceed until the curable fluoropolymer or perfluoropolymer in the composition is substantially cured, preferably at least 90% or more cured. Preferred curing temperatures and times for preferred curable fluoropolymer and / or perfluoropolymer compositions depend on the polymer, but may be, for example, about 5 to about 40 minutes and about 150°C to about 250°C. After curing, post-curing steps may be used as needed. Examples of preferred post-curing temperatures and times for preferred perfluoropolymers specified herein are, for example, about 5 to about 48 hours and about 200°C to about 360°C.

[0186] While curing, the curable compositions described herein can be cured simultaneously using the heat and pressure applied to the mold to form a molded article. Preferably, the combined curable fluoropolymer and perfluoropolymer are formed into a preform, such as an extruded rope or other shape, which is useful for inserting the preform into a mold having a recess shaped to accommodate the preform, and for forming a molded article while curing. Post-curing, if necessary, can also be carried out preferably under air or an inert gas, such as nitrogen.

[0187] Additional curing agents and curing accelerators for either working with or accelerating the curing of fluoropolymers or perfluoropolymers, or for curing and / or accelerating the curing of curable polymers as needed, may also be included herein. Non-curable fluoropolymers or perfluoropolymers include those without reactive curing sites and formed from one or more ethylenically unsaturated monomers (such as TFE, HFP, and PAVE). Additional curable perfluoropolymers may have curing sites suitable for crosslinking with any of the curable perfluoropolymers specified herein and organic peroxide curing systems known in the art, such as bisaminophenyl-based curing. Such polymers may be added to develop alternative blends and to modify the properties of the compositions specified herein.

[0188] In addition to using carbon nanostructures in the elastomer matrices specified above, various polymer matrices useful for forming parts and components (including rigid seals such as certain gaskets) can be used in either QTC or EFI and / or RFI shield end applications. However, it is more preferable to incorporate the carbon nanostructure additives herein into the elastomer matrices described above. For use as primary matrix components in QTC end applications, for example, for forming self-sensing compressible gaskets or medical parts or components, the polymers may be various homopolymers, copolymers, or blends or alloys of such polymers. Preferred polymers are those known to be suitable for use with conductive fillers or additives and may include thermoplastics.

[0189] Examples of suitable matrix polymers include polyarylene polymers (such as polyether ketones, polyether ether ketones, and polyether ketone ketones), melt-processable thermoplastic fluoropolymers (such as hexafluoropropylene-perfluoroalkyl vinyl ether copolymers and fluorinated ethylene-propylene polymers), polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, chlorofluoropolymers, silicon-based polymers, and non-curable fluoropolymers and perfluoropolymers, polyolefins (such as polyethylene and polypropylene (including high-density and low-density types of such polyolefins)), polyethylene terephthalate, polysiloxane, polyurethane, polyaramid, polyamide, polyimide, polyetherimide, polyphenylene sulfide, polyphenylene sulfone, polyethersulfone, polyamideimide, polybenizumidizol, polycarbonate, polyacrylonitrile-butadiene-styrene, polybutadiene-styrene, polyepoxides, and similar materials, as well as their blends, copolymers, alloys, and other combinations.

[0190] In the compositions and various end components and applications described herein, when a carbon nanostructure additive is incorporated into the above-mentioned polymer or curable polymer to form an article, the carbon nanostructure may be combined with other known QTCs, or EMI and / or RFI shielding additives, or other suitable additives for use in the required end application, or with the selected matrix polymer described above. In certain embodiments described herein, such three-dimensional, branched and / or crosslinked carbon nanostructure additives may be combined with other standard conductive fillers (such as carbon powder, flake or fiber fillers), metal-plated glass, metal-plated particles of other metals (such as nickel, aluminum or copper) or polymer fillers, nickel-coated graphite, graphene, graphite, carbon black, graphene derivatives, standard single-walled or multi-walled carbon nanotubes, gold, silver, nickel, copper, and combinations or mixtures thereof. Such additional conductive additives may be present in amounts ranging from about 0.25 parts by weight to about 100 parts by weight per 100 parts by weight of the matrix polymer, provided that no conductive filler is present in amounts that would unnecessarily interfere with, or if not otherwise substantially affect, the beneficial properties of the polymer and carbon nanostructures in the curable polymer as described herein for its intended end use.

[0191] The present invention will now be described with respect to the following non-limiting embodiments. [Examples]

[0192] (Example 1) In this example, the formulation was prepared for use in EMF or RFI shielding end applications. The composition prepared according to the present invention was compared to industrial standards for these specific end applications, which are formulated with a fluorosilicone matrix and nickel-coated graphite filler. Such materials are inexpensive as base polymers and can be filled in large quantities, thus allowing them to be used as standard products for this end application. This material is available as Stockwell 80, a commercial product from Stockwell Elastomerics Inc. This material was tested with various samples formed on O-rings to test 214 sample sizes. Some were bonded to aluminum plates. The samples were mounted in a miniature valve modified for heating. This valve was cycled at a rate of 1 cycle / 2 seconds. Test samples were loaded into the valve and heat was applied. Clean, filtered air was passed through the valve during the cycle and subjected to a particle counter. Particle counts were collected throughout the entire test.

[0193] Comparative samples of Stockwell 80 fluorosilicone (FMVQ) containing nickel-graphite fillers were used in this example, along with samples 1-7 prepared using fluoroelastomer (FKM) and perfluoroelastomer (FFKM) compositions. In the perfluoroelastomer composition, Lodestar's PFK-300 polymer was incorporated into a composition having 40 parts of Cabot® CNS pellets, which are three-dimensional branched carbon nanostructures having interconnecting tubes, per 100 parts of curable polymer. This composition also contains 1.6 parts of bisaminophenol (BOAP) curing agent and 3 parts of Fomblin® oil for processability per 100 parts of curable polymer. The fluoroelastomer composition used contained 100 parts of Tecnoflon® FOR 801HS as the curable polymer, each based on 100 parts by weight of curable polymer, with 50 parts of the same Cabot carbon nanostructure additive and 9 parts by weight of Electromag® 170. These compositions were tested in accordance with Table 1, and the results of particle formation are shown in Figure 1. [Table 1]

[0194] As expected for its final commercial use, the comparative sample after percolation exhibited good resistivity, with particles continuously released at the indicated number over time. In each test sample, initial surface release or percolation release occurred, followed by a rapid decrease in particle size to significantly lower levels over time. Compared to the commercial standard, the particle size level of the present invention sample at use is considerably lower.

[0195] Further compounds were formed using the above-mentioned fluoroelastomer FKM containing various amounts of Cabot carbon nanostructure additive and various amounts of Fomblin® oil, as a control in this test, using the initial composition of Sample 4 in Table 2, to demonstrate volume resistivity (ohms-cm) under a 20 lb load. As observed, the samples according to the present invention not only resulted in substantially lower particle size compared to commercially acceptable state-of-the-art samples, but also exhibited superior conductivity and volume resistivity levels of less than 0.5 ohms-cm. This data is shown in Table 2 below. [Table 2] (Example 2)

[0196] In this example, compositions according to the present invention were prepared that exhibit properties suitable for use in QTC elastomer composite materials. The compositions were formed using Tecnoflon® VPL X75545 fluoroelastomer, i.e., peroxide-curable FKM. The same Cabot carbon nanostructures in pellet form used in Example 1 were formulated at various weight levels based on 100 parts by weight of Tecnoflon®-based polymer. Peroxide curing systems containing Varox® DBPH-50 peroxide curing agent and triallyl isocyanurate (TAIC) DLC co-curing agent were also included as curing additives. Additional fillers included Austin Black 325 (a non-conductive carbon filler useful for processability due to its plate-like structure) and Cancarb low-level conductive thermal carbon black N-990, available as Thermax®. Due to the size of the fillers, the Thermax® additive did not interfere with the interconnected structure formed by the network of carbon nanostructures.

[0197] The properties of samples 13-21 were tested, and their physical properties and formulations are shown in Table 3 below. [Table 3]

[0198] In initial screening, testing of samples containing 0–4.8 parts by weight of carbon nanostructure additive per 100 parts by weight of curable polymer demonstrated that at least approximately 4.8 parts by weight of carbon nanostructure additive in the formulation provided an appropriate amount for measuring volume resistivity. Further testing was performed using O-ring morphological samples 12–20 and buttons containing carbon nanostructure additive in amounts of 4.8–9.6 parts by weight per 100 parts by weight of curable polymer. Volume resistivity was measured using a Ketihley 2410, employing both cross-sectional and four-point probe testing methods.

[0199] As can be seen in Fig. 2, in the case of Samples 13 to 17, when no load was applied, it was found that the volume resistivity decreased as the content of the carbon nanostructure additive increased. Once a load was applied, it was clear that there was a QTC effect. When a 5% deflection was applied, as shown in Fig. 2, in the case of Sample 13 having 4.8 parts by weight of the additive, the volume resistivity decreased to one-fourth. The same tendency was observed in the four samples 14 to 17.

[0200] Referring to Samples 18 to 21 and Fig. 3, the optimum QTC effect was achieved with such a formulation of a carbon nanostructure additive at a level of 4.25 to 4.5 parts by weight per 100 parts by weight of the curable polymer for the QTC effect that seems to be useful for the evaluation of seal erosion as a measure of resistance and the evaluation of compression set as a function of resistance in a semiconductor valve. These characteristics for those Samples 18 to 21 are shown in Fig. 3. Sample 18 has the same formulation as Sample 13 but was prepared and tested independently of Samples 19 to 21.

[0201] When testing the buttons and referring to Fig. 4, Button Samples 22 to 26 were tested, prepared from the compositions of Samples 13 to 17 respectively, and it can be seen that the volume resistivity decreases as the carbon nanostructure additive increases twice from 4.8 parts to 9.6 parts. At a certain level of the carbon nanostructure additive, the volume resistivity initially decreases as the deflection increases from 5% to 10%. When the deflection increases beyond 10%, the volume resistivity increases. (Example 3)

[0202] In this example, the Sample KF seal was prepared using a compound formulation having the carbon nanostructure additive according to the present invention. The seal was made in ISO standard 2861-1 size ISO40 (referred to herein as the "KF-40" seal). These seals were subjected to a conductivity test.

[0203] The QTC formulations listed in Table 4 below were prepared and tested to identify preferred composite material formulations, and KF-40 composite material seals were prepared. The compositions were formed using Lodestar PFK-300, a curable perfluoroelastomer polymer cured using bisaminophenol (BOAP) curing agent, as in Example 1. Cabot carbon nanostructures in pellet form, as used in Examples 1 and 2 above, were incorporated in this example at various levels within a range measured on a part-by-weight basis per 100 parts by weight of PFK-300-based polymer. The additional fillers used in the first five samples prepared (samples 27, 28, 29, 30, and 31) included 3% Austin Black 325 (a non-conductive carbon filler useful for processability due to its plate-like structure) used in Example 2, and 5% conductive thermal carbon black N-990 from Cancarb, available as Thermax®, which can be used without interfering with the interconnected network structure formed by the carbon nanostructures within the cured polymer matrix due to its particle size.

[0204] The remaining samples (samples 32-40) were formed using the same method as samples 27-31, but without the Austin Black 325 or Thermax® N-990 additives. Instead, only the filler was used, consisting of Cabot carbon nanostructure pellets in an amount ranging from 4 to 12 parts per percent of the base polymer PFK-300. [Table 4]

[0205] Samples 32-40 were prepared by first weighing the required components individually into containers. The mill and mixer were preheated to 80°F. PFK-300-based polymer was passed through the mill to produce a thin sheet. BOAP (2,2-bis[3-amino-4-hydroxyphenyl]hexafluoropropane, also known as diamino-bisphenol AF) was added to the container containing the Cabot carbon nanostructures, and the mixture was stirred until both components were completely mixed. The mixture of BOAP and carbon nanostructures was slowly added to the top of the polymer film sheet while the mixer was running at 15 RPM. All components were then stirred for 2 minutes, or until the mixture reached a temperature of 160°F. Next, batches were dropped from the mixer and sheeted on the mill using a nip. This mixture was cut and blended again on the mill for 1 minute, and the cutting and blending process was repeated 5 more times. After the 5th cycle, the material was again sheeted. After 12 hours of aging, the sheet was passed through the mill two more times, and then removed. Approximately five samples of KF-40 seals were prepared from each sheet to be tested using the click-and-die procedure, where the material was cut with an ID / OD clicker die. The die-cut material was then cut into long strips and wrapped in a compression mold.

[0206] Conductivity / resistivity was measured using a four-point probe configuration, as shown in the schematic diagram in Figure 5. Compressions from 0 to 30% were applied to samples 29-31 and 37-40, as shown in Figures 6, 7, and 8. Figure 6 shows samples 29-31 with all three types of fillers in their conductive behavior at various levels of carbon nanostructures: 8, 10, and 12 percent, respectively. Conductivity increases up to approximately 10% deflection and then decreases. Figure 7 shows that for samples with only 8, 10, 12, and 14 percent amounts of carbon nanostructure additives, samples with more fillers show a greater surge in conductivity, but all demonstrate that conductivity improves between 5 and 15% compressions and then begins to plateau. However, the smaller the value, the smaller the effect of the change in conductivity. Figure 8 shows the comparative behavior between a sample containing carbon black filler with carbon nanostructures (samples 29-31) and a sample containing only carbon nanostructures derived from samples 37-40.

[0207] In all samples, a similar pattern of increased conductivity accompanied by deflection, followed by a leveling off, was achieved, demonstrating that the samples were affected by the QTC composite effect under reduced pressure.

[0208] Alternatively, the KF-40 seal for testing can also be fabricated by extruding the material using the cross section of a 210 O-ring.

[0209] To use the composition in a QTC smart seal, a seal constructed using the compositions of this specification, such as the composition of Example 3 above, can be connected to a circuit that measures resistivity to capture changes in the conductivity of the seal under compression, for example. This data can be communicated by any preferred method, either wired connection or wireless communication. An example of a resistance system used in a four-point probe configuration is shown in Figure 9, in which four leads are connected and the resistivity is communicated to a resistivity measuring system through this system. This system can be further connected using a small printed circuit board (PCB) that communicates with the measured resistance on the seal, and an LED light can be used to indicate when the appropriate compression is reached during installation.

[0210] Those skilled in the art will understand that modifications can be made to the above embodiments without departing from the broad concept of the present invention. Therefore, it will be understood that the present invention is not limited to the specific embodiments disclosed, but is intended to encompass modifications within the spirit and scope of the invention as defined by the appended claims. In one embodiment, for example, the following items are provided. (Item 1) A composition for forming an article, At least one matrix polymer selected from the group consisting of at least one thermoplastic polymer and at least one curable polymer having at least one functional group for crosslinking, and A three-dimensional, branched and / or crosslinked carbon nanostructure additive is supplied in such quantities after forming an article from the composition that the article is conductive and has a volume resistivity level of about 0.5 ohms-cm or less. A composition containing the following: (Item 2) The composition according to item 1, wherein, when formed into an article, the article is an electromagnetic interference shielding article and / or a radio frequency interference shielding article. (Item 3) The composition according to item 1, wherein the at least one matrix polymer is at least one curable polymer selected from the group consisting of a curable polymer comprising at least one silicon-containing monomer, a curable polymer comprising at least one monomer containing silicon and fluorine, a curable copolymer comprising at least one acrylonitrile monomer and at least one butadiene monomer, a curable polymer comprising at least one olefin monomer, a curable polymer comprising at least one fluorinated monomer, a curable polymer comprising at least one perfluorinated monomer, and blends and copolymers thereof. (Item 4) The composition according to item 3, wherein, upon curing, the cured polymer composition comprises one or more elastomers selected from the group consisting of silicones, fluorosilicones, fluoroelastomers, perfluoropolyethers, perfluoroelastomers, and cured elastomers formed from blends and copolymers thereof. (Item 5) The composition according to item 3, wherein the at least one curable polymer is selected from the group consisting of curable fluorinated polymers and curable perfluorinated polymers. (Item 6) The composition according to item 5, wherein the at least one curable polymer is at least one curable perfluorinated polymer. (Item 7) The composition according to item 5, wherein the at least one curable polymer is a blend or copolymer of at least one curable fluoropolymer and at least one curable perfluoropolymer. (Item 8) The composition according to item 1, wherein the matrix polymer is at least one curable polymer having at least one functional group for crosslinking, and the composition further comprises at least one crosslinking additive for reacting with the at least one functional group for crosslinking. (Item 9) The composition according to item 8, wherein, upon curing of the curable polymer composition, the resulting cured material is used for electromagnetic interference shielding or radio frequency interference shielding applications. (Item 10) The carbon nanostructure additive has a carbon content higher than or equal to approximately 97%, and approximately 0.135 g / cm³. 3 The composition according to item 1, having a bulk density of . (Item 11) The composition according to item 1, further comprising at least one filler different from the at least one nanostructure additive. (Item 12) The composition according to item 1, comprising about 0.1 parts by weight to about 300 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 13) The composition according to item 12, comprising about 0.25 to about 250 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 14) The composition according to item 13, comprising about 0.5 to about 250 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 15) The composition according to item 14, comprising about 0.5 to about 80 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 16) The composition according to item 1, wherein the at least one matrix polymer is selected from the group consisting of at least one curable fluoropolymer, at least one curable perfluoropolyether, and at least one curable perfluoropolymer, and the composition contains about 10 to about 80 parts by weight of the carbon nanostructure additive per 100 parts by weight of the at least one matrix polymer. (Item 17) The composition according to item 16, wherein the composition comprises about 10 to about 50 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 18) The composition according to item 17, wherein the composition comprises about 20 to about 40 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 19) The composition according to item 1, wherein the matrix polymer is a thermoplastic polymer selected from the group consisting of polyarylene polymers, melt-processable thermoplastic fluoropolymers, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, chlorofluoropolymers, silicon-based polymers, as well as non-curable fluoropolymers and perfluoropolymers, polyolefins, polyethylene terephthalate, polysiloxanes, polyurethanes, polyaramids, polyamides, polyimides, polyetherimides, polyphenylene sulfide, polyphenylene sulfone, polyethersulfone, polyamideimides, polybenizumidizol, polycarbonates, polyacrylonitrile-butadiene-styrene, polybutadiene-styrene, polyepoxides, and similar materials, as well as blends, copolymers, alloys, and other combinations thereof. (Item 20) The composition according to item 1, further comprising one or more conductive fillers, different from the carbon nanostructure additive, which are powders, flakes, or fiber fillers comprising one or more of carbon, metal-plated glass, or metal-plated particles, wherein the particles comprise metals or polymers, nickel-coated graphite, graphene, graphite, carbon black, graphene derivatives, single-walled carbon nanotubes, multi-walled carbon nanotubes, gold, silver, nickel, copper, and combinations or mixtures thereof. (Item 21) The composition according to item 20, wherein the composition comprises about 0.25 parts by weight to about 100 parts by weight of one further conductive filler, different from the carbon nanostructure additive, per 100 parts by weight of the at least one matrix polymer. (Item 22) Elastomer articles and / or thermoplastic articles formed from the compositions described in item 1. (Item 23) The article described in item 22, wherein the article is selected from gaskets, seals, covers, and component parts for use in an electromagnetic interference shielding device or a radio frequency interference device. (Item 24) Thermoplastic polymers, and / or at least one curable fluoropolymer, at least one curable perfluoropolyether, at least one perfluoropolymer, at least one curable polymer containing silicon and fluorine, and at least one matrix polymer having at least one functional group for crosslinking selected from copolymers and blends thereof, and Approximately 5 to 300 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. A composition for electromagnetic interference shielding and / or radio frequency interference shielding, comprising: When the composition is cured and formed into an article, the article has a volume resistivity level of about 0.5 ohms-cm or less. The carbon nanostructure additive is three-dimensional, branched, and crosslinked. Composition for electromagnetic interference shielding and / or radio frequency interference shielding. (Item 25) The electromagnetic interference shielding and / or radio frequency interference shielding composition according to item 24, wherein the at least one matrix polymer is at least one curable perfluoropolymer, and the composition comprises about 10 parts by weight to about 80 parts by weight of the carbon nanostructure additive per 100 parts by weight of the at least one curable polymer. (Item 26) The aforementioned at least one carbon nanostructure additive has a carbon content higher than or equal to about 97%, and about 0.135 g / cm³. 3 The composition according to item 24, having a bulk density of . (Item 27) At least one matrix polymer selected from thermoplastic polymers and / or curable polymers having at least one functional group for crosslinking, as well as After the formation of an article from the composition, the article is supplied with a three-dimensional, branched and / or crosslinked carbon nanostructure additive in an amount that demonstrates one or more of the dissipative effect and the quantum tunneling composite effect. A composition containing the following: (Item 28) The composition according to item 27, comprising about 1 to about 30 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 29) The composition according to item 28, comprising about 1 to about 15 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 30) The composition according to item 27, wherein when an article is formed from the composition, the article has a quantum tunneling effect, and the composition comprises at least about 2 parts by weight of the carbon nanostructure additive per 100 parts by weight of the at least one matrix polymer. (Item 31) The composition according to item 30, wherein the composition comprises at least about 3 parts by weight of the carbon nanostructure additive per 100 parts by weight of the at least one matrix polymer. (Item 32) The composition according to item 31, wherein the composition comprises at least about 4 parts by weight of the carbon nanostructure additive per 100 parts by weight of the at least one matrix polymer. (Item 33) The composition according to item 32, wherein the composition comprises about 4 parts by weight to about 20 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 34) The composition according to item 33, wherein the composition comprises about 4 to about 15 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. (Item 35) The composition according to item 27, wherein the matrix polymer is a thermoplastic polymer selected from the group consisting of polyarylene polymers, melt-processable thermoplastic fluoropolymers, polyvinyl chloride, polyvinylidene fluoride, polytetrafluoroethylene, chlorofluoropolymers, silicon-based polymers, as well as non-curable fluoropolymers and perfluoropolymers, polyolefins, polyethylene terephthalate, polysiloxanes, polyurethanes, polyaramids, polyamides, polyimides, polyetherimides, polyphenylene sulfide, polyphenylene sulfone, polyethersulfone, polyamideimides, polybenizumidizol, polycarbonates, polyacrylonitrile-butadiene-styrene, polybutadiene-styrene, polyepoxides, and similar materials, as well as blends, copolymers, alloys, and other combinations thereof. (Item 36) The composition according to item 27, further comprising at least one conductive filler, different from the carbon nanostructure additive, selected from the group consisting of powders, flakes, and fiber fillers, which include one or more of carbon, metal-plated glass, and metal-plated particles, wherein the particles include metal or polymer, nickel-coated graphite, graphene, graphite, carbon black, graphene derivatives, single-walled carbon nanotubes, multi-walled carbon nanotubes, gold, silver, nickel, copper, and combinations or mixtures thereof. (Item 37) The composition according to item 36, comprising about 0.25 parts by weight to about 100 parts by weight of one more conductive filler, different from the carbon nanostructure additive, per 100 parts by weight of at least one matrix polymer. (Item 38) An article formed from the composition described in item 27. (Item 39) The article according to item 38, wherein the article is an elastomer quantum tunnel composite material, selected from the group consisting of seals, gaskets or other components in a sealing assembly. (Item 40) The article described in item 38, wherein the article is an insulator when not subjected to compressive stress, and conductive when subjected to compressive stress. (Item 41) The article described in item 38, wherein the article is an elastomer quantum tunnel composite material and is a self-sensing article; when the article is in a state of electrical communication with a circuit and voltage is applied, when the article is in use and subjected to compressive stress, a change in the conductivity of the article is measured, and the change in conductivity is used to determine and evaluate the performance of the article in real time. (Item 42) A method for manufacturing an article, A step of preparing a composition comprising at least one matrix polymer selected from thermoplastic polymers and / or curable polymers having at least one functional group for crosslinking, and at least one three-dimensional, branched and / or crosslinked carbon nanostructure additive, wherein the at least one carbon nanostructure additive is present in an amount of about 0.1 parts by weight to about 300 parts by weight per 100 parts by weight of the at least one matrix polymer, and A step of forming an article from the composition by thermoforming the composition, or by curing and thermoforming the composition, wherein the article can be used as at least one of an electromagnetic shielding device and a radio frequency shielding device. Methods that include... (Item 43) The method according to item 42, wherein the article has a volume resistivity of about 0.5 ohms-cm or less. (Item 44) The method according to item 42, wherein the at least one matrix polymer is a curable polymer, and the composition further comprises at least one crosslinking additive for reacting with at least one functional group for crosslinking. (Item 45) The method according to item 42, wherein the article is selected from seals, gaskets, covers, or component parts of electromagnetic interference shielding devices and / or radio frequency interference shielding devices. (Item 46) A method for manufacturing an article, A step of preparing a composition comprising at least one matrix polymer selected from thermoplastic polymers and / or curable polymers having at least one functional group for crosslinking, and at least one three-dimensional, branched and crosslinked carbon nanostructure additive, wherein the at least one carbon nanostructure additive is present in an amount of about at least about 1 part by weight to about 30 parts by weight per 100 parts by weight of the at least one matrix polymer, and A step of forming an article from the composition by thermoforming the composition, or by curing and thermoforming the composition, wherein the article exhibits at least one of the dissipative effect or the quantum tunneling effect. Methods that include... (Item 47) The method according to item 46, wherein the article is a seal, gasket or other component in a sealing assembly. (Item 48) The method according to item 46, wherein the matrix polymer is a curable polymer, and the composition comprises at least one crosslinking additive for reacting with at least one functional group for crosslinking. (Item 49) The method according to item 46, wherein the curable polymer is selected from the group consisting of curable fluoropolymers, curable perfluoropolyethers and curable perfluoropolymers, and blends and copolymers thereof. (Item 50) The method according to item 46, wherein the article is an elastomer quantum tunneling composite material. (Item 51) The method according to item 46, wherein the article is an insulator when not subjected to compressive stress and conductive when subjected to compressive stress. (Item 52) The method according to item 46, wherein the article is conductive when not subjected to compressive stress and has a different conductivity level than the conductivity level when the article is subjected to compressive stress. (Item 53) The method according to item 52, wherein the conductivity level of the article when subjected to compressive stress is higher than the conductivity level of the article when not subjected to compressive stress. (Item 54) The method according to item 46, wherein the article is an elastomer quantum tunnel composite material and is a self-sensing article; when the article is in a state of electrical communication with a circuit and a voltage is applied, when the article is in use and subjected to compressive stress, a change in the conductivity of the article is measured, and the change in conductivity is used to determine and evaluate the performance of the article in real time.

Claims

1. A composition for forming an article, At least one matrix polymer, which is at least one curable polymer having at least one functional group for crosslinking, and A three-dimensional, branched and / or crosslinked carbon nanostructure additive is supplied in such quantities that, after forming an article from the composition, the article is conductive and has a volume resistivity level of 0.5 ohms-cm or less, and is an electromagnetic interference shielding article and / or a radio frequency interference shielding article. A composition containing the following:

2. The composition according to claim 1, wherein the at least one matrix polymer is at least one curable polymer selected from the group consisting of a curable polymer comprising at least one silicon-containing monomer, a curable polymer comprising at least one monomer containing silicon and fluorine, a curable copolymer comprising at least one acrylonitrile monomer and at least one butadiene monomer, a curable polymer comprising at least one olefin monomer, a curable polymer comprising at least one fluorinated monomer, a curable polymer comprising at least one perfluorinated monomer, and blends and copolymers thereof.

3. The composition according to claim 2, wherein, upon curing, the cured polymer composition comprises one or more elastomers selected from the group consisting of silicones, fluorosilicones, fluoroelastomers, perfluoropolyethers, perfluoroelastomers, and cured elastomers formed from blends and copolymers thereof.

4. The composition according to claim 2, wherein at least one curable polymer is selected from the group consisting of curable fluorinated polymers and curable perfluorinated polymers.

5. The composition according to claim 4, wherein the at least one curable polymer is at least one curable perfluorinated polymer.

6. The composition according to claim 4, wherein the at least one curable polymer is a blend or copolymer of at least one curable fluoropolymer and at least one curable perfluoropolymer.

7. The composition according to claim 1, further comprising at least one crosslinking additive for reacting with at least one functional group for crosslinking.

8. The carbon nanostructure additive has a carbon content higher than or equal to 97%, and 0.135 g / cm³. ３ The composition according to claim 1, having a bulk density of .

9. The composition according to claim 1, further comprising at least one filler different from the at least one nanostructure additive.

10. The composition according to claim 1, comprising 0.1 to 300 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

11. The composition according to claim 10, comprising 0.25 to 250 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

12. The composition according to claim 11, comprising 0.5 to 250 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

13. The composition according to claim 12, comprising 0.5 to 80 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

14. The composition according to claim 1, wherein the at least one matrix polymer is selected from the group consisting of at least one curable fluoropolymer, at least one curable perfluoropolyether, and at least one curable perfluoropolymer, and the composition contains 10 to 80 parts by weight of the carbon nanostructure additive per 100 parts by weight of the at least one matrix polymer.

15. The composition according to claim 14, wherein the composition comprises 10 to 50 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

16. The composition according to claim 15, wherein the composition comprises 20 to 40 parts by weight of the carbon nanostructure additive per 100 parts by weight of at least one matrix polymer.

17. The composition according to claim 1, further comprising one or more conductive fillers, different from the carbon nanostructure additive, which are powders, flakes, or fiber fillers comprising one or more of carbon, metal-plated glass, and metal-plated particles, wherein the particles comprise metals or polymers, nickel-coated graphite, graphene, graphite, carbon black, graphene derivatives, single-walled carbon nanotubes, multi-walled carbon nanotubes, gold, silver, nickel, copper, and combinations or mixtures thereof.

18. The composition according to claim 17, wherein the composition comprises 0.25 to 100 parts by weight of one or more conductive fillers different from the carbon nanostructure additive, per 100 parts by weight of at least one matrix polymer.

19. An elastomer article formed from the composition described in claim 1.

20. The article according to claim 19, wherein the article is selected from gaskets, seals, covers, and component parts for use in an electromagnetic interference shielding device or a radio frequency interference device.

21. At least one matrix polymer which is a curable polymer having at least one functional group for crosslinking selected from copolymers and blends thereof, and at least one curable polymer comprising at least one curable fluoropolymer, at least one curable perfluoropolyether, at least one perfluoropolymer, silicon and fluorine, and at least one matrix polymer which is a curable polymer selected from thereof copolymers and blends, 5 to 300 parts by weight of carbon nanostructure additive per 100 parts by weight of at least one matrix polymer. A composition for electromagnetic interference shielding and / or radio frequency interference shielding, comprising: When the composition is cured and formed into an article, the article has a volume resistivity level of 0.5 ohms-cm or less. The carbon nanostructure additive is three-dimensional, branched, and crosslinked. When the composition is formed on an article, the article is an electromagnetic interference shielding article and / or a radio frequency interference shielding article. Composition for electromagnetic interference shielding and / or radio frequency interference shielding.

22. The electromagnetic interference shielding and / or radio frequency interference shielding composition according to claim 21, wherein the at least one matrix polymer is at least one curable perfluoropolymer, and the composition comprises 10 to 80 parts by weight of the carbon nanostructure additive per 100 parts by weight of the at least one curable polymer.

23. The at least one carbon nanostructure additive has a carbon content higher than or equal to 97%, and 0.135 g / cm³. ３ The composition according to claim 21, having a bulk density of .

24. A method for manufacturing an article, A step of preparing a composition comprising at least one matrix polymer which is at least one curable polymer having at least one functional group for crosslinking, and at least one three-dimensional, branched and / or crosslinked carbon nanostructure additive, wherein the at least one carbon nanostructure additive is present in an amount of 0.1 to 300 parts by weight per 100 parts by weight of the at least one matrix polymer, and A step of forming an elastomer article from the composition by either thermoforming the composition or curing and thermoforming the composition, wherein the elastomer article can be used in at least one of an electromagnetic shielding device and a radio frequency shielding device. Methods that include...

25. The method according to claim 24, wherein the elastomer article has a volume resistivity of 0.5 ohms-cm or less.

26. The method according to claim 24, wherein the composition further comprises at least one crosslinking additive for reacting with at least one functional group for crosslinking.

27. The method according to claim 24, wherein the elastomer article is selected from seals, gaskets, covers, or component parts of electromagnetic interference shielding devices and / or radio frequency interference shielding devices.

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