Automatically cured and molded high-temperature sealing material and application thereof

Abstract

The invention provides an automatic curing molding high-temperature sealing material and application thereof, and belongs to the technical field of polymer sealing materials. The anaerobic curing sealant shows excellent high-temperature resistance after being cured, can stably work in an environment of 200-300 DEG C for a long time, has excellent chemical corrosion resistance, can resist various corrosive media such as acid, alkali and hydrocarbons, has excellent vibration fatigue resistance, remarkably prolongs the service life of a sealing system, and is suitable for large-scale popularization and application. The device can be applied to high-temperature, high-pressure and corrosive medium environments. The sealing material is particularly suitable for connecting and sealing threads and flanges of high-temperature and high-pressure systems such as chemical pipelines and gas pipelines, the problem that liquid anaerobic adhesive construction is inconvenient is solved, the defect of high-temperature performance of a traditional sealing material is overcome, and the sealing material has important industrial application value.

Description

Technical Field

[0001] The present invention relates to the technical field of polymer sealing materials, and in particular to an automatically solidified high-temperature sealing material and applications thereof. Background Art

[0002] In industries like chemical, petroleum, and gas, the sealing performance of pipeline systems is directly related to the safe operation of equipment and the prevention of media leakage. Due to assembly gaps in threaded pipe joints and flange connections, traditional sealing materials (such as PTFE tape, rubber gaskets, or spiral wound gaskets) are susceptible to aging, creep, or chemical degradation in environments with high temperatures (above 200°C), high pressures, or highly corrosive media, leading to seal failure. Furthermore, vibration can exacerbate loosening of sealing interfaces, further increasing the risk of leakage.

[0003] While existing anaerobic liquid raw tapes can cure and fill microgaps in the absence of oxygen, they can only withstand temperatures between -30°C and 130°C, and can withstand temperatures up to 150°C for short periods. They cannot withstand temperatures above 150°C. Furthermore, their liquid nature makes them difficult to apply and difficult to maintain in vertical or large gaps. Existing solid sealing tapes (such as modified silicone tapes) are easy to preform, but they typically rely on heat or UV curing, making uniform curing difficult in complex assembly structures. They also have limited high-temperature tolerance (generally below 150°C). Summary of the Invention

[0004] The purpose of the present invention is to provide a high-temperature sealing material that is automatically cured and formed and its application. The sealing material has the advantages of convenient construction (preformed strip shape), anaerobic self-curing properties, long-term high temperature resistance (≥200°C) and chemical corrosion resistance, which can meet the long-term sealing requirements under harsh working conditions and solve the performance deficiencies of existing sealing materials in high temperature, high pressure and corrosive environments.

[0005] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0006] The present invention provides a high-temperature sealing material that is automatically cured and formed, comprising a fiber-based carrier and an oxygen-free curing sealant loaded on the fiber-based carrier;

[0007] The oxygen-free curing sealant comprises the following raw materials in parts by mass:

[0008] 1-60 parts of composite monomer, 1-40 parts of modified resin, 1-60 parts of rubber polymer, 0.01-15 parts of catalyst, 1-30 parts of heat-resistant modifier, 0.01-10 parts of stabilizer, 1-60 parts of filler, 0.1-10 parts of thixotropic agent, 0.1-25 parts of plasticizer;

[0009] The heat-resistant modifier is bismaleimide.

[0010] Preferably, the composite monomer includes one or more of an acrylate monomer, a monofunctional methacrylate monomer, a difunctional methacrylate monomer, a multifunctional methacrylate monomer and an aromatic monomer;

[0011] The acrylate monomer includes C4-C 24 Straight chain acrylate, C4-C 24 Branched acrylate, C4-C 24 At least one of cyclic alkyl acrylate, hydroxyl-containing acrylate, ether bond-containing acrylate and heterocyclic acrylate; the mass of the acrylic monomer is 1 to 35% of the mass of the oxygen-free curing sealant;

[0012] The chemical formula of the monofunctional methacrylate monomer is CH2=C(CH3)-COOR1, wherein R1 is C1-C 20 Straight chain hydrocarbon or C1-C2 containing hydroxyl, ether bond or cyclic structure 20 Group; the mass of the monofunctional methacrylate monomer is 1 to 50% of the mass of the oxygen-free curing sealant;

[0013] The chemical formula of the difunctional methacrylate monomer is [CH2=C(CH3)-COO]2-R2, wherein R2 is C2-C 30 Alkylene, polyether chain segment or bisphenol structural group; the mass of the bifunctional methacrylate monomer is 1 to 60% of the mass of the oxygen-free curing sealant;

[0014] The multifunctional methacrylate monomer is a C6-C 50 Polyol ester; the mass of the multifunctional methacrylate monomer is 1 to 60% of the mass of the oxygen-free curing sealant;

[0015] The aromatic monomer includes a methacrylate monomer containing a phenyl group, a phenyl derivative group, a naphthyl group or a naphthyl derivative group; the mass of the aromatic monomer is 1 to 60% of the mass of the oxygen-free curing sealant.

[0016] Preferably, the modified resin includes one or more of glycidyl ether epoxy resin, alicyclic epoxy resin and glycidyl amine epoxy resin; the glycidyl ether epoxy resin includes bisphenol A epoxy resin and / or bisphenol F epoxy resin.

[0017] Preferably, the rubber polymer includes butadiene-acrylonitrile copolymer and / or polyurethane-modified polybutadiene.

[0018] Preferably, the catalyst includes a curing accelerator, an adhesion promoter and an initiator;

[0019] The curing accelerator includes one or more of o-benzoylsulfonimide, N,N'-dimethyl-p-toluidine, N,N-diethyl-p-toluidine and acetylphenylhydrazine;

[0020] The adhesion promoter includes one or more of oxalic acid, p-toluenesulfonic acid and maleic acid;

[0021] The initiator includes benzoyl peroxide, cumene hydroperoxide and / or tert-butyl hydroperoxide;

[0022] The mass of the curing accelerator is 0.1-5% of the total mass of the oxygen-free curing sealant, the mass of the adhesion promoter is 0.1-5% of the total mass of the oxygen-free curing sealant, and the mass of the initiator is 0.1-6% of the total mass of the oxygen-free curing sealant.

[0023] Preferably, the bismaleimide comprises N-phenylmaleimide and / or 4,4'-methylenediphenylene bismaleimide.

[0024] Preferably, the stabilizer includes one or more of 1,4-naphthoquinone, 1,4-p-benzoquinone, 4-methoxyphenol, hydroquinone and tetraalkali metal salt of ethylenediaminetetraacetic acid.

[0025] Preferably, the filler comprises one or more of polyethylene, polytetrafluoroethylene, polyvinyl chloride, polypropylene, polyester, polystyrene and polyimide;

[0026] The thixotropic agent includes one or more of fumed silica, hydrogenated castor oil and polyamide wax powder;

[0027] The plasticizer includes one or more of polyethylene glycol monooleate, polyethylene glycol dioleate, propylene glycol and diethylene glycol dibenzoate (DEDB).

[0028] Preferably, the fiber-based carrier includes non-woven fabric or organic fiber filaments; the non-woven fabric includes spunlace non-woven fabric, spunbond non-woven fabric, meltblown non-woven fabric, needle-punched non-woven fabric, wet-laid non-woven fabric or heat-bonded non-woven fabric; the material of the non-woven fabric is polyester or polypropylene, and the basis weight of the non-woven fabric is 20 to 100 g / m 2 ; The organic fiber filaments include polyester fiber filaments, polyamide fiber filaments, polyacrylonitrile fiber filaments or polyolefin fiber filaments, and the fineness of the organic fiber filaments is 500~3000D.

[0029] The present invention provides the application of the automatically solidified high-temperature sealing material described in the above technical solution in the field of sealing in high-temperature, high-pressure and corrosive medium environments.

[0030] The present invention provides a high-temperature sealing material that is automatically cured and formed. The sealing material is made of a unique oxygen-free curing sealant and has the following advantages:

[0031] Heat resistance: Bismaleimide (BMI) resin is compounded with a fiber-based carrier in the sealing material and activates the cross-linking reaction at high temperature to form a rigid aromatic ring and a three-dimensional cross-linked network structure, which effectively inhibits the thermal motion of the polymer chain, thereby maintaining strength above 300°C and reducing high-temperature creep; at the same time, curing in an oxygen-free environment can avoid oxidative degradation and significantly improve thermal stability.

[0032] Corrosion resistance: After curing, the anaerobic sealant forms an inert barrier through the dense cross-linked polymer film and the hydrophobic groups in its molecular chain (such as BMI benzene ring) to block the penetration of corrosive media. At the same time, the reinforced skeleton composed of the fiber-based carrier can reduce the microcracks caused by mechanical stress, thereby achieving physical and chemical dual protection in the acid-base alternating environment of chemical equipment, and can effectively block the penetration of corrosive media such as water, acid, and salt.

[0033] High-pressure resistance: When under pressure, the anaerobic sealant can flow and fill the microscopic bumps on the metal surface (Ra≤3.2μm). After curing, it forms a mechanical interlock with the substrate to withstand local pressures above 40MPa. At the same time, the longitudinally oriented non-woven fabric / organic fiber filaments enhance the anti-extrusion performance, ensuring that the sealant will not be squeezed out and fail in a high-pressure environment.

[0034] The self-curing components and mechanism of the oxygen-free curing sealant of the present invention are as follows: the acrylate monomers (mono-, di-, poly-, and aromatic) and the initiation system (peroxide + metal ion catalyst in the metal substrate, the metal ion activates the decomposition of the peroxide) in the oxygen-free curing sealant inhibit free radical polymerization due to dissolved oxygen during storage. After assembly, the metal interface isolates oxygen and triggers the metal ion to reduce the peroxide to produce active free radicals, which in turn initiates chain polymerization of the acrylate double bonds and copolymerizes with the maleimide groups of the BMI resin to form an interpenetrating network structure (IPN), ultimately achieving high-strength curing. Therefore, the sealing material of the present invention combines the ease of use of a preformed strip structure with the technical characteristics of oxygen-free self-curing, effectively overcoming the problem of traditional sealing materials being prone to failure under harsh working conditions.

[0035] The anaerobic curing sealant of the present invention exhibits excellent high-temperature resistance after curing and can operate stably in an environment of 200-300°C for a long time. It also has excellent resistance to chemical corrosion and can withstand a variety of corrosive media such as acids, alkalis, and hydrocarbons. It also has excellent anti-vibration fatigue properties, significantly improving the service life of the sealing system and can be used in high-temperature, high-pressure, and corrosive media environments. The sealing tape of the present invention is particularly suitable for sealing threaded and flange connections in high-temperature and high-pressure systems such as industrial water supply and drainage pipes, chemical pipelines, and gas pipelines. It not only solves the problem of inconvenient construction of liquid anaerobic adhesives, but also makes up for the shortcomings of traditional sealing tapes in high-temperature performance, and has important industrial application value.

[0036] The sealing material of the present invention can be automatically solidified and formed after assembly and pressing in an oxygen-free environment. It is suitable for sealing threaded pipe joints, flange connections and other parts in the fields of industrial water supply and drainage, chemical pipelines, gas pipelines, oil transportation systems, etc., especially for pipeline sealing needs that need to withstand high temperatures (above 200°C) for a long time, chemical corrosion and vibration conditions. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 This is a physical picture of the automatically solidified high-temperature sealing material of the present invention. DETAILED DESCRIPTION

[0038] In the present invention, unless otherwise specified, the required raw materials or reagents are commercially available products well known to those skilled in the art.

[0039] The present invention provides a high-temperature sealing material that is automatically cured and formed, comprising a fiber-based carrier and an oxygen-free curing sealant loaded on the fiber-based carrier;

[0040] The oxygen-free curing sealant comprises the following raw materials in parts by mass:

[0041] 1-60 parts of composite monomer, 1-40 parts of modified resin, 1-60 parts of rubber polymer, 0.01-15 parts of catalyst, 1-30 parts of heat-resistant modifier, 0.01-10 parts of stabilizer, 1-60 parts of filler, 0.1-10 parts of thixotropic agent, 0.1-25 parts of plasticizer;

[0042] The heat-resistant modifier is bismaleimide.

[0043] The self-curing high-temperature sealing material provided by the present invention includes a fiber-based carrier; the fiber-based carrier preferably includes a non-woven fabric or organic fiber filaments; the non-woven fabric preferably includes a spunlace non-woven fabric, a spunbond non-woven fabric, a meltblown non-woven fabric, a needle-punched non-woven fabric, a wet-laid non-woven fabric or a heat-bonded non-woven fabric; the material of the non-woven fabric is preferably polyester or polypropylene, and the polyester is preferably polyethylene terephthalate (PET); the basis weight of the non-woven fabric is preferably 20 to 100 g / m 2, more preferably 40 to 60 g / m 2 ; The organic fiber filaments include polyester fiber filaments, polyamide fiber filaments, polyacrylonitrile fiber filaments or polyolefin fiber filaments, and the fineness of the organic fiber filaments is 500~3000D, more preferably 2000D.

[0044] In the present invention, when the fiber-based carrier is a non-woven fabric, the loading amount of the oxygen-free curing sealant on the fiber-based carrier is preferably 150 to 350 g / m2 based on the wet weight of the sealant. 2 , more preferably 200 to 250 g / m 2 ; In actual application, it can be adjusted according to the porosity of the carrier and the density of the sealant.

[0045] When the fiber-based carrier is an organic fiber filament, the mass ratio of the oxygen-free curing sealant to the fiber-based carrier is preferably 1 to 1.5:1, more preferably 1 to 1.2:1.

[0046] This invention uses a flexible non-woven fabric or organic fiber filament as a carrier, loaded with an oxygen-free curing sealant, making it easy to wrap around or adhere to sealing surfaces such as threads and flanges. After lamination, the metal interface oxygen barrier allows the material to rapidly crosslink and cure in an oxygen-free environment, forming a dense, durable sealing layer without the need for additional heating or light.

[0047] The automatically solidified high-temperature sealing material provided by the present invention comprises an oxygen-free solidifying sealant supported on the fiber-based carrier.

[0048] In the present invention, the raw materials for preparing the oxygen-free curing sealant include 1 to 60 parts by mass of the composite monomer, preferably 34.8 to 50 parts, and more preferably 36 to 40 parts.

[0049] In the present invention, the composite monomer preferably includes one or more of an acrylate monomer, a monofunctional methacrylate monomer, a difunctional methacrylate monomer, a multifunctional methacrylate monomer and an aromatic monomer.

[0050] In the present invention, the acrylate monomer preferably includes C4-C 24 Straight chain acrylate, C4-C 24 Branched acrylate, C4-C 24 At least one of cyclic alkyl acrylate, hydroxyl-containing acrylate, ether bond-containing acrylate and heterocyclic acrylate; the mass of the acrylic monomer is preferably 1-35% of the mass of the oxygen-free curing sealant, more preferably 5-15%.

[0051] In the present invention, the acrylic acid ester monomer is more preferably one or more of hydroxyethyl acrylate (CAS 818-61-1), 2-hydroxypropyl acrylate (CAS 25584-83-2), isobornyl acrylate (CAS 5888-33-5), tetrahydrofuryl acrylate (CAS 2399-48-6), lauryl acrylate (CAS 2156-97-0), 2-ethylhexyl acrylate (CAS 103-11-7), and cyclohexyl acrylate (CAS 3066-71-5).

[0052] In the present invention, the chemical formula of the monofunctional methacrylate monomer is preferably CH2=C(CH3)-COOR1, wherein R1 is C1-C 20 Straight chain hydrocarbon or C1-C2 containing hydroxyl, ether bond or cyclic structure 20 the mass of the monofunctional methacrylate monomer is preferably 1 to 50% of the mass of the oxygen-free curing sealant, and more preferably 10 to 15%.

[0053] In the present invention, the monofunctional methacrylate monomer preferably includes one or more of hydroxyethyl methacrylate (CAS 868-77-9), 2-hydroxypropyl methacrylate (CAS 27813-02-1), isobornyl methacrylate (CAS 7534-94-3), tetrahydrofuryl methacrylate (CAS 2455-24-5), lauryl methacrylate (CAS 142-90-5), 2-ethylhexyl methacrylate (CAS 688-84-6), cyclohexyl methacrylate (CAS 101-43-9), and dimethylaminoethyl methacrylate (CAS 2867-47-2).

[0054] In the present invention, the chemical formula of the difunctional methacrylate monomer is preferably [CH2=C(CH3)-COO]2-R2, wherein R2 is C2-C 30 Alkylene, polyether segment or bisphenol structural group; the mass of the bifunctional methacrylate monomer is 1 to 60% of the mass of the oxygen-free curing sealant, more preferably 20 to 33.6%.

[0055] In the present invention, the bifunctional methacrylate monomer preferably includes one or more of 1,6-hexanediol dimethacrylate (CAS 6606-59-3), ethylene glycol dimethacrylate (CAS 97-90-5), diethylene glycol dimethacrylate (CAS 2358-84-1), triethylene glycol dimethacrylate (CAS 109-16-0), polyethylene glycol dimethacrylate (CAS 25852-47-5), ethoxylated bisphenol A dimethacrylate (CAS 41637-38-1), bisphenol A dimethacrylate (CAS 1565-94-2), and polyurethane diacrylate (such as Sartomer, product model CN9010NS).

[0056] In the present invention, the multifunctional methacrylate monomer is preferably a C6-C 50 polyol ester; the mass of the multifunctional methacrylate monomer is 1 to 60% of the mass of the oxygen-free curing sealant, more preferably 10 to 28%.

[0057] In the present invention, the multifunctional methacrylate monomer preferably includes one or more of trimethylolpropane trimethacrylate (CAS 3290-92-4), pentaerythritol trimethacrylate (CAS 3524-68-3), pentaerythritol tetramethacrylate (CAS 3253-82-5), and di(trimethylolpropane) tetramethacrylate (CAS 68478-45-5).

[0058] In the present invention, the aromatic monomer preferably includes a methacrylate monomer containing a phenyl group, a phenyl derivative group, a naphthyl group or a naphthyl derivative group; the mass of the aromatic monomer is 1 to 60% of the mass of the oxygen-free curing sealant, more preferably 10 to 20%.

[0059] In the present invention, the aromatic (meth)acrylate monomer preferably includes benzyl methacrylate (CAS 2495-37-6), phenyl methacrylate (CAS 2177-70-0), phenoxyethyl methacrylate (CAS 10595-06-9), and naphthyl methacrylate (CAS 2023-83-4).

[0060] Based on the mass fraction of the composite monomer, the raw materials for preparing the oxygen-free curing sealant include 1 to 40 parts of modified resin, preferably 3.6 to 30 parts, and more preferably 5 to 5.5 parts.

[0061] In the present invention, the modified resin preferably includes one or more of glycidyl ether epoxy resin, alicyclic epoxy resin and glycidyl amine epoxy resin; when the modified resin is two or more of the above-mentioned types, the present invention has no special limitation on the ratio of different types of modified resins, which can be adjusted according to needs.

[0062] In the present invention, the glycidyl ether epoxy resin preferably includes bisphenol A epoxy resin (EPON 828, CAS 25068-38-6) and / or bisphenol F epoxy resin (EPON 862, CAS 28064-14-4); the alicyclic epoxy resin is preferably ERL-4221 (CAS 2386-87-0); and the glycidyl amine epoxy resin is preferably MY 720 (CAS 28768-32-3).

[0063] Based on the mass fraction of the composite monomer, the raw materials for preparing the oxygen-free curing sealant include 1 to 60 parts of rubber polymer, preferably 8 to 30 parts, more preferably 10.2 to 15 parts, and even more preferably 11.5 to 13 parts.

[0064] In the present invention, the rubber polymer preferably includes a butadiene-acrylonitrile copolymer and / or a polyurethane-modified polybutadiene.

[0065] In the present invention, the butadiene-acrylonitrile copolymer is preferably vinyl-terminated nitrile rubber (VTBN, Mn = 3,000-4,000 g / mol, AN content: 10-26%), carboxyl-terminated nitrile rubber (CTBN, Mn = 3,000-4,000 g / mol, AN content: 10-26%) or amine-terminated nitrile rubber (ATBN, Mn = 3,000-4,000 g / mol, AN content: 10-26%).

[0066] In the present invention, the vinyl content of the polyurethane-modified polybutadiene is preferably 65%, and Mn=3000 g / mol.

[0067] Based on the mass fraction of the composite monomer, the raw materials for preparing the oxygen-free curing sealant include 0.01 to 15 parts of catalyst, preferably 3.3 to 7.98 parts, and more preferably 6.16 to 7.98 parts.

[0068] In the present invention, the catalyst preferably includes a curing accelerator, an adhesion promoter and an initiator; the mass of the curing accelerator is preferably 0.1 to 5% of the total mass of the anaerobic curing sealant, more preferably 0.75 to 1.5%, and further preferably 0.8 to 1.3%; the mass of the adhesion promoter is preferably 0.1 to 5% of the total mass of the anaerobic curing sealant, more preferably 0.75 to 3.5%, and further preferably 1.36 to 2.86%; the mass of the initiator is preferably 0.1 to 6% of the total mass of the anaerobic curing sealant, more preferably 0.95 to 2.36%, and further preferably 1.95 to 2.86%.

[0069] In the present invention, the curing accelerator preferably includes one or more of o-benzoylsulfonyl imide (saccharin, CAS 81-07-2), N,N'-dimethyl-p-toluidine (DMT, CAS 99-97-8), N,N-diethyl-p-toluidine (DEpT, CAS 91-67-8) and acetophenylhydrazine (APH, CAS 114-83-0);

[0070] The adhesion promoter preferably includes one or more of oxalic acid (CAS144-62-7), p-toluenesulfonic acid (CAS104-15-4) and maleic acid (CAS110-16-7);

[0071] The initiator preferably includes benzoyl peroxide (BPO, CAS 94-36-0), cumene hydroperoxide (CPH, CAS 80-15-9) and / or tert-butyl hydroperoxide (TBH, CAS 75-91-2).

[0072] Based on the mass fraction of the composite monomer, the raw materials for preparing the oxygen-free curing sealant include 1 to 30 parts of heat-resistant modifier, preferably 10.5 to 20 parts, and more preferably 12.5 to 13.5 parts.

[0073] In the present invention, the heat-resistant modifier is bismaleimide; the bismaleimide preferably includes N-phenylmaleimide (CAS 941-69-5) and / or 4,4'-methylenediphenylene bismaleimide (CAS 13676-54-5).

[0074] Based on the mass fraction of the composite monomer, the raw materials for preparing the oxygen-free curing sealant include 0.01 to 10 parts of stabilizer, preferably 0.03 to 5 parts, and more preferably 0.67 to 0.8 parts.

[0075] In the present invention, the stabilizer preferably includes one or more of 1,4-naphthoquinone, 1,4-p-benzoquinone, 4-methoxyphenol, hydroquinone and tetraalkali metal salt of ethylenediaminetetraacetic acid.

[0076] In the present invention, the tetraalkali metal salt of ethylenediaminetetraacetic acid is preferably tetrasodium ethylenediaminetetraacetic acid.

[0077] The raw materials for preparing the oxygen-free curing sealant include 1 to 60 parts of filler, preferably 20 to 26 parts, and more preferably 21 to 24 parts, based on the mass fraction of the composite monomer. The filler includes one or more of polyethylene (PE) powder, polytetrafluoroethylene (PTFE) powder, polyvinyl chloride (PVC) powder, polypropylene (PP) powder, polyester (PET) powder, polystyrene (PS), and polyimide (PI) powder.

[0078] The raw materials for preparing the oxygen-free curing sealant include 0.1 to 10 parts, preferably 2.25 to 3.94 parts, and more preferably 3.15 to 3.67 parts, of a thixotropic agent, based on the mass fraction of the composite monomer. The thixotropic agent preferably includes one or more of fumed silica (CAB-O-SILTS 720), hydrogenated castor oil (CAS 36377-33-0), and polyamide wax powder (Disparlon 6500).

[0079] The raw materials for preparing the anaerobic curing sealant include 0.1 to 25 parts of a plasticizer, preferably 3 to 5 parts, and more preferably 3.5 to 4.6 parts, based on the mass fraction of the composite monomer. In the present invention, the plasticizer preferably includes one or more of polyethylene glycol monooleate (CAS 9004-96-0), polyethylene glycol dioleate (CAS 9005-07-6), propylene glycol (CAS 57-55-6), and diethylene glycol dibenzoate (CAS 120-55-8).

[0080] The present invention has no particular limitation on the preparation method of the oxygen-free curing sealant. The materials may be mixed uniformly according to a process well known in the art.

[0081] In an embodiment of the present invention, specifically, the components except the initiator are stirred and dispersed at 60°C ± 2 (1000 rpm / min) for 90 minutes; after the initiator is added at below 40°C (more preferably 35°C), the mixture is stirred and dispersed at 400 rpm / min for 30 minutes to obtain an oxygen-free curing sealant.

[0082] In the present invention, the method for preparing the automatically solidified high-temperature sealing material is preferably a dipping molding method or a blade coating molding method.

[0083] In the present invention, the dipping molding method is preferably to immerse the fiber-based carrier into the oxygen-free curing sealant, and then cut the coating to obtain the sealing material after controlling the coating thickness to 0.05 to 0.5 mm by rolling or scraping. The dipping molding method is preferably completed using a dipping machine.

[0084] In the present invention, the scraping molding method is preferably to pre-coat the oxygen-free curing sealant on the fiber-based carrier, and then cut it into pieces after controlling the thickness to 0.05-0.5 mm by rolling to obtain the sealing material; the scraping molding method is preferably completed using a scraper coater.

[0085] The present invention has no special limitation on the coating speed of the dipping machine and the coating speed of the scraper coater, and they can be adjusted according to actual needs to achieve the required thickness.

[0086] The self-curing high temperature sealing material of the present invention is preferably in the form of a sealing tape or a sealing rope. Figure 1 .

[0087] When used, the high-temperature sealing material of the present invention is wrapped around the threaded joint 3-5 times and squeezed (after pressing) to achieve oxygen barrier through the metal interface so that the material can be quickly cross-linked and cured under oxygen-isolated conditions, achieving dual sealing of physical filling and chemical curing to form a dense and durable sealing layer.

[0088] The present invention provides the application of the automatically solidified high-temperature sealing material described in the above technical solution in the field of sealing in high-temperature, high-pressure and corrosive media environments. The present invention has no particular limitation on the method of application, and the application can be carried out according to methods well known in the art.

[0089] The specific embodiments of the present invention are described in detail below, but it should be understood that the scope of protection of the present invention is not limited by the specific embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention. The experimental methods described in the embodiments of the present invention are all conventional methods unless otherwise specified.

[0090] The following experimental methods and detection methods, unless otherwise specified, are conventional methods; the following reagents and raw materials, unless otherwise specified, are commercially available.

[0091] Example 1

[0092] The formula of the oxygen-free curing sealant in this embodiment is shown in Table 1.

[0093] Among them, bisphenol A epoxy resin (EPON 828, CAS25068-38-6);

[0094] Vinyl-terminated nitrile butadiene rubber (VTBN, Mn = 3,000-4,000 g / mol, AN content: 10-26%) was purchased from Huntsman;

[0095] The fumed silica was CAB-O-SILTS720.

[0096] Table 1 Formulation of oxygen-free curing sealant in Example 1

[0097]

[0098] Preparation method:

[0099] Preparation of oxygen-free curing sealant:

[0100] The components except the initiator were stirred and dispersed at 60°C±2 (1000 rpm / min) for 90 minutes; after adding the initiator at 35°C±2, the mixture was stirred and dispersed at 400 rpm / min for 30 minutes to obtain a paste-like oxygen-free curing sealant.

[0101] Sealing tape preparation: Polyester PET (basic weight 40g / m 2 ) Spunbond nonwoven fabric is used as the substrate, and oxygen-free curing sealant is evenly coated using a comma blade coater. The coating speed is controlled at 5m / min, the coating thickness is 0.2mm±0.05mm, and the sealant loading is 250g / m 2 After coating is completed, the material is cut into rolls with a width of 10-50 mm according to usage requirements to obtain sealing materials.

[0102] Example 2

[0103] The formula of the oxygen-free curing sealant in this embodiment is shown in Table 2.

[0104] Among them, bisphenol A epoxy resin (EPON 828, CAS25068-38-6);

[0105] Carboxyl-terminated nitrile rubber (CTBN, Mn=3,000-4,000 g / mol, AN content: 10-26%) was purchased from Huntsman; fumed silica was CAB-O-SIL TS720.

[0106] Table 2 Formulation of oxygen-free curing sealant in Example 2

[0107]

[0108] The preparation method of the oxygen-free curing sealant and the sealing tape is the same as that in Example 1.

[0109] Example 3

[0110] The formula of the oxygen-free curing sealant in this embodiment is shown in Table 3.

[0111] Wherein, the alicyclic epoxy resin is ERL-4221 (CAS2386-87-0);

[0112] The polyurethane-modified polybutadiene has a vinyl content of 65% and Mn=3000 g / mol and was purchased from Huntsman;

[0113] The polyamide wax powder is Disparlon 6500.

[0114] Table 3 Formulation of oxygen-free curing sealant in Example 3

[0115]

[0116] The preparation method of the oxygen-free curing sealant and the sealing tape is the same as that in Example 1.

[0117] Example 4

[0118] The formula of the oxygen-free curing sealant in this embodiment is shown in Table 4.

[0119] Among them, the alicyclic epoxy resin is ERL-4221 (CAS2386-87-0);

[0120] Carboxyl-terminated nitrile rubber (Mn=3,000-4,000 g / mol, AN content: 10-26%); purchased from Huntsman;

[0121] Table 4: Formulation of oxygen-free curing sealant in Example 4

[0122]

[0123]

[0124] The preparation method of the oxygen-free curing sealant and the sealing tape is the same as that in Example 1.

[0125] Example 5

[0126] The formula of the oxygen-free curing sealant in this embodiment is shown in Table 5.

[0127] Among them, bisphenol A epoxy resin (EPON 828, CAS25068-38-6);

[0128] Vinyl-terminated nitrile rubber (Mn=3,000-4,000 g / mol, AN content: 10-26%), purchased from Huntsman;

[0129] Polyamide wax powder (Disparlon 6500);

[0130] Table 5: Formulation of oxygen-free curing sealant in Example 5

[0131]

[0132] The preparation method of the oxygen-free curing sealant is the same as that in Example 1.

[0133] Preparation of sealing rope: polyamide fiber filament with a fineness of 2000D is used as the base material, and a coating thickness of 0.2mm±0.05mm is applied by a dipping machine at a uniform speed of 40m / min. The mass ratio of sealant to fiber-based carrier is 1:1. The sealing rope is cut into coils with a specification of 10-50m to obtain a sealing material.

[0134] Example 6

[0135] The formula of the oxygen-free curing sealant in this embodiment is shown in Table 6.

[0136] Among them, bisphenol A epoxy resin (EPON 828, CAS25068-38-6);

[0137] Vinyl-terminated nitrile butadiene rubber (VTBN, Mn = 3,000-4,000 g / mol, AN content: 10-26%), purchased from Huntsman;

[0138] Polyamide wax powder (Disparlon 6500);

[0139] Table 6 Formulation of oxygen-free curing sealant in Example 6

[0140]

[0141] The preparation method of the oxygen-free curing sealant and the sealing tape is the same as that in Example 1.

[0142] Comparative Example 1

[0143] The only difference from Example 5 is that after removing the heat-resistant modifier, it is replaced with equal amounts of monofunctional monomers and filler components. The specific formula is shown in Table 7.

[0144] Table 7 Sealant formulation in Comparative Example 1

[0145]

[0146]

[0147] The preparation method of the sealant and the sealing tape is the same as that of Example 1.

[0148] Performance Testing

[0149] 1) Curing performance test

[0150] Purpose of the test:

[0151] Evaluate the curing speed and full cure time of sealing materials in an oxygen-free environment to ensure they can quickly form a stable sealant layer in actual applications. By measuring the initial and full cure times, the reactivity of the sealant in different formulations is verified, providing a reference for construction technology.

[0152] Experimental equipment: high and low temperature test chamber (model: WGDY-7350L, -70℃~350℃), electronic timer, pipeline pressure and temperature tester (model: PT-5000) equipped with 0.01 precision electronic temperature and pressure gauge.

[0153] Test standard: Initial curing time and complete curing time test are carried out according to "JB / T 7311-2016 Technical Conditions for Anaerobic Adhesives".

[0154] 1) The sealing materials prepared in Examples 1 to 6 and Comparative Example 1 were subjected to curing performance tests. The results are shown in Table 8.

[0155] Table 8 Curing properties of sealing materials in Examples 1 to 6 and Comparative Example 1

[0156]

[0157]

[0158] As shown in Table 8, the curing time is affected by the monomer type and the catalyst ratio. Examples 3, 4, 5, 6 and Comparative Example 1, in which the proportion of multifunctional monomers is high, cure faster.

[0159] 2) High temperature resistance test

[0160] Purpose of the test:

[0161] Verify the sealing stability of sealing materials under long-term high temperature (300°C) and short-term peak temperature (350°C) to ensure their suitability for high-temperature working conditions (such as chemical pipelines). By simulating actual high-temperature environments, test the thermal aging resistance and high-temperature creep performance of the materials.

[0162] Experimental equipment: high and low temperature test chamber (model: WGDY-7350L, -70℃~350℃), pipeline pressure and temperature tester (model: PT-5000) equipped with 0.01 precision electronic temperature and pressure gauge, carbon steel threaded pipe (DN15).

[0163] Specific test method:

[0164] When the sealing performance of the pipeline threaded interface of the sealing materials prepared in Examples 1 to 6 and Comparative Example 1 was tested, a DN15 standard carbon steel threaded pipe was selected and the surface of the external thread was cleaned. The sealing tape to be tested was evenly wrapped around the external thread in a clockwise winding manner for 3 turns, and then the threaded connection was tightened with a torque wrench according to a standard torque of 50 Nm. In the long-term temperature resistance test (steady-state test), the assembled sample was placed in a high and low temperature test chamber, pressurized at a constant pressure of 4 MPa, heated to 300°C ± 2°C and maintained at a constant temperature. The timing was started and the initial leakage time (first leakage) and the final failure time (complete loss of sealing) were observed and recorded. In the short-term peak test (limit test), a new sample was prepared under the same assembly conditions. After being placed in the test chamber, the temperature was quickly raised to 350°C ± 2°C and a constant pressure of 4 MPa was immediately applied. The duration from the start of pressurization to the occurrence of leakage was recorded. The results are shown in Table 9.

[0165] Table 9 High temperature resistance of sealing materials at pipe threaded joints in Examples 1 to 6 and Comparative Example 1

[0166]

[0167]

[0168] As shown in Table 9, bismaleimide can significantly improve heat resistance (Examples 1, 2, 3, 4, 5, and 6 perform better than Comparative Example 1).

[0169] 3) Chemical corrosion resistance test

[0170] Purpose of the test:

[0171] Analyze the chemical stability of sealing materials in corrosive media such as acids, alkalis, and hydrocarbons to ensure their long-term suitability in harsh environments such as chemical and petroleum industries. Evaluate the material's volume change rate and mechanical property retention through immersion testing.

[0172] Experimental equipment:

[0173] Constant temperature immersion tank (model: HWS-26), electronic balance (accuracy 0.001g), vernier caliper.

[0174] Test method: According to GB / T 1690-2010 Test method for liquid resistance of vulcanized rubber or thermoplastic rubber, the sealing materials prepared in Examples 1 to 6 and Comparative Example 1 were cut into standard sizes (25 mm × 25 mm × 2 mm) after curing, and immersed in 10% H2SO4, 10% NaOH, and diesel for 72 hours, and the volume change rate was measured.

[0175] The chemical corrosion resistance of the sealing materials in Examples 1 to 6 and Comparative Example 1 is shown in Table 10.

[0176] Table 10 Chemical corrosion resistance test of sealing materials after curing (72 hours immersion)

[0177]

[0178] As shown in Table 10, high-proportion multifunctional monomers filled with PTFE and (PTFE+PI) fillers (Examples 3, 5, and Comparative Example 1) have the best chemical resistance and stability, and can meet the long-term sealing requirements of harsh industrial environments such as chemical and petroleum industries.

[0179] 4) Vibration fatigue resistance test

[0180] Purpose of the test:

[0181] Simulate dynamic vibration environments (such as mechanical vibration of pipelines) to test the durability of sealing materials under the combined effects of high temperature and vibration. Verify their resistance to microcrack growth and interface bonding strength to ensure the long-term effectiveness of the sealing system under vibration conditions.

[0182] Experimental equipment: temperature and humidity three-in-one vibration test chamber (model: DR-H207, frequency range 5-4000Hz, temperature range -70℃ to +350℃), fully automatic water-vapor dual-purpose pressure test pump (pressure range 0-6MPa, equipped with 0.01 accuracy electronic pressure gauge), carbon steel threaded pipe simulation device (specification DN32, surface roughness Ra≤3.2μm, material ASTMA105 carbon steel) and data acquisition system (real-time recording of vibration frequency, amplitude, pressure changes and leakage).

[0183] Specific test method:

[0184] The sealing material to be tested was evenly wrapped clockwise around the threaded sealing area of ​​a carbon steel threaded pipe simulator three times and tightened with a torque of 50 Nm. The assembled simulator was placed in a temperature and humidity three-in-one vibration test chamber, heated to the target temperature (300 ± 2°C) and maintained at that temperature for 15 minutes. The high-frequency vibration tester was then activated, with the vibration parameters set to 50 Hz frequency and 1 mm amplitude. The test was conducted continuously for 72 hours under a constant water pressure of 4 MPa.

[0185] The vibration fatigue resistance test of the sealing materials in Examples 1, 3 and 5 and Comparative Example 1 is shown in Table 11.

[0186] Table 11 Vibration fatigue resistance test of different sealing materials

[0187] Case Vibration time to failure (h) Failure Mode Example 1 >72 (not expired) No leakage Example 3 >72 (not expired) No leakage Example 5 >72 (not expired) No leakage Comparative Example 1 8 Interface cracking

[0188] As can be seen from Table 11, the present invention realizes dynamic high-temperature testing through a temperature and humidity three-in-one vibration test chamber, and combines multiple failure monitoring of pressure, leakage and morphology analysis to verify that the synergistic effect of its bismaleimide-reinforced three-dimensional cross-linked network and fiber carrier gives the sealing tape excellent durability in a high-temperature vibration environment, effectively inhibiting high-temperature creep and vibration fatigue crack propagation.

[0189] 5) Comparative test with traditional materials

[0190] Purpose of the test:

[0191] Comparing the performance differences between the sealing material of the present invention and traditional liquid anaerobic adhesives or solid sealing tapes, the advantages of the sealing material in terms of ease of construction, temperature resistance, and curing speed are highlighted. Its industrial application value is demonstrated through quantitative indicators.

[0192] Experimental equipment: pressure tester (PT-5000), high temperature oven, construction simulation platform.

[0193] Test standard: Refer to JB / T 7311-2016 Technical Requirements for Anaerobic Adhesives to compare construction ease, curing time, and temperature resistance.

[0194] The sealing materials in Examples 3 and 5 of the present invention were compared with traditional commercially available materials. The results are shown in Table 12.

[0195] Table 12 Performance comparison of the sealing materials in Example 3 and Example 5 and the commercially available Hangtai brand 150 anaerobic liquid raw tape

[0196]

[0197] As can be seen from Table 12, the sealing tape / rope of the present invention has better high-temperature stability. It adopts a dual sealing design of physical caulking and anaerobic self-curing chemistry, which greatly improves the sealing performance. At the same time, it gets rid of the dependence of construction on external conditions, significantly shortens the pressure test time, significantly improves the convenience and efficiency of construction, and effectively reduces the waste rate. It fully meets the requirements of harsh working conditions such as chemical pipelines and gas pipelines, and its industrial applicability is significantly better than that of traditional anaerobic liquid raw tape sealing materials.

[0198] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A high-temperature sealing material that is automatically solidified and formed, characterized in that: It includes a fiber-based carrier and an oxygen-free curing sealant supported on the fiber-based carrier; The oxygen-free curing sealant comprises the following raw materials in parts by mass: 1-60 parts of composite monomer, 1-40 parts of modified resin, 1-60 parts of rubber polymer, 0.01-15 parts of catalyst, 1-30 parts of heat-resistant modifier, 0.01-10 parts of stabilizer, 1-60 parts of filler, 0.1-10 parts of thixotropic agent, 0.1-25 parts of plasticizer; The heat-resistant modifier is bismaleimide.

2. The automatically curing high temperature sealing material according to claim 1, characterized in that: The composite monomer includes one or more of an acrylate monomer, a monofunctional methacrylate monomer, a difunctional methacrylate monomer, a multifunctional methacrylate monomer and an aromatic monomer; The acrylate monomer includes C4-C 24 Straight chain acrylate, C4-C 24 Branched acrylate, C4-C 24 At least one of cyclic alkyl acrylate, hydroxyl-containing acrylate, ether bond-containing acrylate and heterocyclic acrylate; the mass of the acrylic monomer is 1 to 35% of the mass of the oxygen-free curing sealant; The chemical formula of the monofunctional methacrylate monomer is CH2=C(CH3)-COOR1, wherein R1 is C1-C 20 Straight chain hydrocarbon or C1-C2 containing hydroxyl, ether bond or cyclic structure 20 Group; the mass of the monofunctional methacrylate monomer is 1 to 50% of the mass of the oxygen-free curing sealant; The chemical formula of the difunctional methacrylate monomer is [CH2=C(CH3)-COO]2-R2, wherein R2 is C2-C 30 Alkylene, polyether chain segment or bisphenol structural group; the mass of the bifunctional methacrylate monomer is 1 to 60% of the mass of the oxygen-free curing sealant; The multifunctional methacrylate monomer is a C6-C 50 Polyol ester; the mass of the multifunctional methacrylate monomer is 1 to 60% of the mass of the oxygen-free curing sealant; The aromatic monomer includes a methacrylate monomer containing a phenyl group, a phenyl derivative group, a naphthyl group or a naphthyl derivative group; the mass of the aromatic monomer is 1 to 60% of the mass of the oxygen-free curing sealant.

3. The automatically curing high temperature sealing material according to claim 1, characterized in that: The modified resin includes one or more of glycidyl ether epoxy resin, alicyclic epoxy resin and glycidyl amine epoxy resin; the glycidyl ether epoxy resin includes bisphenol A epoxy resin and / or bisphenol F epoxy resin.

4. The automatically curing high temperature sealing material according to claim 1, characterized in that: The rubber polymer includes butadiene-acrylonitrile copolymer and / or polyurethane-modified polybutadiene.

5. The automatically curing high temperature sealing material according to claim 1, characterized in that: The catalyst includes a curing accelerator, an adhesion promoter and an initiator; The curing accelerator includes one or more of o-benzoylsulfonimide, N,N'-dimethyl-p-toluidine, N,N-diethyl-p-toluidine and acetylphenylhydrazine; The adhesion promoter includes one or more of oxalic acid, p-toluenesulfonic acid and maleic acid; The initiator includes benzoyl peroxide, cumene hydroperoxide and / or tert-butyl hydroperoxide; The mass of the curing accelerator is 0.1-5% of the total mass of the oxygen-free curing sealant, the mass of the adhesion promoter is 0.1-5% of the total mass of the oxygen-free curing sealant, and the mass of the initiator is 0.1-6% of the total mass of the oxygen-free curing sealant.

6. The automatically curing high temperature sealing material according to claim 1, characterized in that: The bismaleimide includes N-phenylmaleimide and / or 4,4′-methylenediphenylene bismaleimide.

7. The automatically curing high temperature sealing material according to claim 1, characterized in that: The stabilizer includes one or more of 1,4-naphthoquinone, 1,4-p-benzoquinone, 4-methoxyphenol, hydroquinone and tetraalkali metal salt of ethylenediaminetetraacetic acid.

8. The automatically curing high temperature sealing material according to claim 1, characterized in that: The filler includes one or more of polyethylene, polytetrafluoroethylene, polyvinyl chloride, polypropylene, polyester, polystyrene and polyimide; The thixotropic agent includes one or more of fumed silica, hydrogenated castor oil and polyamide wax powder; The plasticizer includes one or more of polyethylene glycol monooleate, polyethylene glycol dioleate, propylene glycol and diethylene glycol dibenzoate.

9. The automatically curing high temperature sealing material according to claim 1, characterized in that: The fiber-based carrier includes non-woven fabric or organic fiber filaments; the non-woven fabric includes spunlace non-woven fabric, spunbond non-woven fabric, meltblown non-woven fabric, needle-punched non-woven fabric, wet-laid non-woven fabric or heat-bonded non-woven fabric; the material of the non-woven fabric is polyester or polypropylene, and the basis weight of the non-woven fabric is 20 to 100 g / m 2 ; The organic fiber filaments include polyester fiber filaments, polyamide fiber filaments, polyacrylonitrile fiber filaments or polyolefin fiber filaments, and the fineness of the organic fiber filaments is 500~3000D.

10. Use of the automatically solidified high-temperature sealing material according to any one of claims 1 to 9 in the field of sealing in high-temperature, high-pressure and corrosive medium environments.

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