Anaerobic adhesive composition, anaerobic adhesive and preparation method of anaerobic adhesive

Abstract

The invention provides an anaerobic adhesive composition, an anaerobic adhesive and a preparation method of the anaerobic adhesive. The anaerobic adhesive composition comprises a main agent and a promoting primer, and the main agent comprises the following components in parts by weight: 30-70 parts of an acrylate monomer, 5-20 parts of an acrylate oligomer, 5-20 parts of a tackifier and 1-10 parts of an amide monomer; the accelerating primer is prepared from the following components in parts by weight: 0.01 to 30 parts of phosphorus-containing acrylate monomer and 0.001 to 1 part of reaction accelerator; wherein the reaction accelerant is an organic compound containing transition metal. According to the anaerobic adhesive composition, the curing degree of the anaerobic adhesive can reach the standard in a short time (within 3 min), and high drawing strength and an excellent damage form are achieved, so that the bonding requirement of a silicon steel sheet of a motor iron core is met; and the anaerobic adhesive has the advantages of high temperature resistance, no cracking, high drawing strength, vibration resistance, good oil-resistant stability and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of anaerobic adhesives, and in particular to an anaerobic adhesive composition, an anaerobic adhesive and a preparation method thereof. Background Art

[0002] In the motor industry, the stator and rotor cores are crucial components, and their quality directly impacts the motor's technical performance. Traditional core manufacturing methods typically involve punching stator and rotor laminations (loose laminations) from conventional dies, then aligning the laminations and riveting, clinching, or welding them using processes like argon arc welding. The rotor cores of AC motors also require manual twisting to create skewed slots. Stepper motors require uniform magnetic properties and thickness for both the stator and rotor cores, and require a certain degree of rotation between the stator and rotor laminations. Traditional manufacturing methods suffer from low efficiency and inability to meet technically demanding precision.

[0003] With the continuous development of motor varieties and assembly processes, adhesive cores have been developed. Compared with two-component acrylic adhesives, two-component epoxy adhesives, and one-component epoxy adhesives, the use of anaerobic adhesives as bonding adhesives for core silicon steel sheet laminations is more efficient, convenient, and energy-saving. Among them, two-component acrylic adhesives or two-component epoxy adhesives need to be mixed evenly in a certain proportion before use, and sometimes heating is required to catalyze curing to shorten the curing time. However, in this process, uneven mixing of the two components is prone to occur, resulting in uncertainties such as substandard pull-out force after curing and unstable curing speed, which affects production. Single-component epoxy adhesives often require heating to initiate curing, and the heating temperature is generally between 100 and 200°C. Therefore, it has the problems of high energy consumption and low production efficiency.

[0004] Existing single-component anaerobic adhesives are used to bond silicon steel sheets. Common problems include low bonding strength, a long time to reach service strength (more than 60 minutes), and poor high temperature resistance (the pull-out force decreases significantly under high temperature conditions). Although anaerobic adhesives used in conjunction with general solvent-based metal ion accelerators for bonding silicon steel sheets solve the problem of curing speed, they also suffer from high dispersibility in bonding strength and low bonding strength, especially peel strength. This is because metal ion chelates can promote reactions but lack the ability to polymerize. Therefore, combining metal ion chelates with polymers of primary or secondary amines can solve the problem of high dispersibility of anaerobic adhesives, but it cannot solve the problem of low strength of anaerobic adhesives. Therefore, there is an urgent need to develop a new type of anaerobic adhesive. Summary of the Invention

[0005] The main purpose of the present invention is to provide an anaerobic adhesive composition, an anaerobic adhesive and a preparation method thereof, so as to solve the problems in the prior art of single-component anaerobic adhesives used for bonding silicon steel sheets, such as low bonding strength, a long time required to reach the use strength and poor high temperature resistance.

[0006] To achieve the above-mentioned object, according to one aspect of the present invention, an anaerobic adhesive composition is provided, comprising a main agent and a accelerator primer, wherein, in parts by weight, the main agent comprises: 30 to 70 parts of an acrylate monomer, 5 to 20 parts of an acrylate oligomer, 5 to 20 parts of a tackifier, and 1 to 10 parts of an amide monomer; and the accelerator primer comprises: 0.01 to 30 parts of a phosphorus-containing acrylate monomer and 0.001 to 1 part of a reaction accelerator; wherein the reaction accelerator is an organic compound containing a transition metal.

[0007] Furthermore, the main agent comprises, by weight, 35 to 65 parts of acrylate monomers, 7 to 18 parts of acrylate oligomers, 7 to 18 parts of tackifiers, and 3 to 8 parts of amide monomers; the primer promoter comprises, by weight, 0.1 to 20 parts of phosphorus-containing acrylate monomers and 0.01 to 0.8 parts of reaction accelerators.

[0008] Furthermore, the mass ratio of the acrylate monomer to the amide monomer in the main agent is 5 to 20:1; and / or the mass ratio of the acrylate oligomer to the tackifier is 0.6 to 2.5:1; and / or the acrylate monomer is a methacrylate monomer and / or a trifunctional acrylate, wherein the methacrylate monomer is selected from any one or more of glycidyl methacrylate, lauric methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, tetrahydrofuran methacrylate, tetrahydrofuran hydroxypropyl methacrylate, triethylene glycol dimethacrylate, ethylene glycol bisphenol A dimethacrylate and hexanediol dimethacrylate; the trifunctional acrylate is selected from any one or more of trimethylolpropane triacrylate, pentaerythritol triacrylate, (3) ethoxylated trimethylolpropane triacrylate, tris(2-hydroxyethyl)isocyanurate triacrylate, any one or more of ester and (3) propoxylated glycerol triacrylate; and / or, the acrylate oligomer is selected from any one or more of aromatic polyurethane acrylate, aliphatic polyurethane acrylate and epoxy acrylate polymer; and / or, the tackifier is selected from any one or more of styrene-butadiene rubber, nitrile rubber, resol resin, styrene, chloroprene rubber, MBS resin, ABS resin, polymethacrylate, polyvinylidene chloride and chlorosulfonated polyethylene; and / or, the amide monomer is an unsaturated amide monomer, the unsaturated amide monomer is a vinylamide compound and / or an acrylamide compound, preferably the vinylamide compound is selected from any one or more of N-vinylsulfonamide, N-vinylcarbonylamide and N-vinyllactam; preferably the acrylamide compound is selected from any one or more of N-acrylsulfonamide, N-acrylcarbonylamide and N-acryllactam.

[0009] Furthermore, the mass ratio of the phosphorus-containing acrylate monomer to the reaction accelerator in the promoting primer is 0.125 to 2000:1; and / or the phosphorus-containing acrylate monomer is selected from ethylene glycol methacrylate phosphate and / or hydroxyethyl methacrylate phosphate; and / or the reaction accelerator is an organic chelated metal complex, the organic chelated metal complex includes a metal salt and an organic ligand, the metal salt is selected from any one or more of copper salts, iron salts, manganese salts, cobalt salts and nickel salts; the organic ligand is selected from any one or more of acetylacetone, ethyl acetoacetate, methacrylic acid, hexanoic acid and naphthoic acid; preferably, the reaction accelerator is any one or more of ferrocene, copper acetylacetonate and copper ethylhexanoate.

[0010] Furthermore, the main agent further comprises, by weight: 0.1 to 2 parts of a stabilizer, 0.1 to 10 parts of an initiator, 0.5 to 15 parts of an accelerator, and 0.1 to 2 parts of an auxiliary accelerator.

[0011] Furthermore, the accelerating primer further comprises 10 to 90 parts by weight of an organic solvent.

[0012] According to another aspect of the present invention, an anaerobic adhesive is provided, which is obtained by mixing an anaerobic adhesive composition, wherein the anaerobic adhesive composition is the above-mentioned anaerobic adhesive composition.

[0013] According to another aspect of the present invention, a method for preparing the above-mentioned anaerobic adhesive is provided, which comprises: step S1, mixing raw materials including acrylate monomers, acrylate oligomers, tackifiers, and amide monomers to obtain a main agent; step S2, mixing raw materials including phosphorus-containing acrylate monomers and reaction accelerators to obtain a promoter primer; wherein the anaerobic adhesive comprises the main agent and the promoter primer.

[0014] Furthermore, the above-mentioned step S1 also includes: step S11, performing a first mixing of raw materials including acrylic acid ester monomers, acrylic acid ester oligomers and tackifiers to obtain a first mixture; step S22, performing a second mixing of raw materials including the first mixture, a stabilizer, a promoter, a co-promoter and an initiator to obtain a second mixture; step S23, performing a third mixing of raw materials including the second mixture and an amide monomer to obtain a main agent; wherein, the rotation speed of the first mixing is 200-800 rpm, and the time of the first mixing is 3-8 hours; and / or, the rotation speed of the second mixing is 300-900 rpm, and the time of the second mixing is 2-6 hours; and / or, the rotation speed of the third mixing is 300-600 rpm, and the time of the third mixing is 0.5-1 hour.

[0015] Furthermore, the above step S2 further includes: performing a fourth mixing of the raw materials including the phosphorus-containing acrylate monomer, the reaction accelerator and the organic solvent to obtain a promoter primer; wherein the fourth mixing speed is 50 to 200 rpm, and the fourth mixing time is 2 to 6 hours.

[0016] By applying the technical solution of the present invention, the present application optimizes the composition and content of the main agent and the primer in the anaerobic adhesive composition within the above range, which can not only make the curing degree of the anaerobic adhesive reach the standard and achieve higher pull-out strength and excellent failure form in a short time (within 3 minutes), thereby meeting the bonding requirements of the motor core silicon steel sheet, but also enable the anaerobic adhesive to have the advantages of resisting high temperature without cracking, maintaining high pull-out strength, anti-vibration and good oil-resistant stability. Specifically, on the one hand, adding an acrylic acid ester monomer to the main agent can rapidly polymerize to form a colloid with a highly cross-linked structure, thereby achieving bonding with the substrate. Adding an amide monomer can improve the bonding strength and pull-out strength of the anaerobic adhesive. Due to the polarity and coordination energy of the amide bond in the molecular chain, the affinity of the amide monomer to the coated silicon steel sheet is significantly increased. Therefore, the anaerobic adhesive prepared has good bonding effect and high pull-out strength. Adding a soluble high-molecular-weight polymer, namely an acrylate oligomer, can improve the peel and pull-out forces of anaerobic adhesives, while also enabling them to withstand high temperatures without cracking, maintain high pull-out strength, and resist vibration. Adding a tackifier can further enhance the adhesion of anaerobic adhesives to various substrates. Furthermore, by adding a reaction promoter containing an oxidizable transition metal organic compound and a phosphorus-containing acrylate monomer to the primer, the adhesion of the anaerobic adhesive to the substrate can be improved, thereby increasing the pull-out force while maintaining a stable cure speed. Therefore, even when bonding anaerobic adhesives to iron cores within a short period of time, the cure level can meet standard requirements, while also meeting pull-out requirements. DETAILED DESCRIPTION

[0017] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The present invention will be described in detail below with reference to the embodiments.

[0018] As analyzed in the background technology of this application, the existing single-component anaerobic adhesive has the problems of low bonding strength, long time required to reach the use strength and high temperature resistance when used for bonding silicon steel sheets. In order to solve the above problems, this application provides an anaerobic adhesive composition, anaerobic adhesive and its preparation method.

[0019] In a typical embodiment of the present application, an anaerobic adhesive composition is provided, comprising a main agent and a accelerator primer, wherein, in parts by weight, the main agent comprises: 30 to 70 parts of an acrylate monomer, 5 to 20 parts of an acrylate oligomer, 5 to 20 parts of a tackifier, and 1 to 10 parts of an amide monomer; in parts by weight, the accelerator primer comprises: 0.5 to 30 parts of a phosphorus-containing acrylate monomer and 0.001 to 1 part of a reaction accelerator; wherein the reaction accelerator is an organic compound containing a transition metal.

[0020] The present application optimizes the composition and content of the main agent and the promoting primer in the anaerobic adhesive composition in the above range, not only can the curing degree of the anaerobic adhesive reach the standard and realize higher pull-out strength and excellent failure form in a short time (within 3min), thereby meeting the bonding requirements of the motor core silicon steel sheet, but also can make the anaerobic adhesive have the advantages of resisting high temperature without cracking, maintaining high pull-out strength, anti-vibration and good oil-resistant stability. Specifically, on the one hand, adding acrylate monomers in the main agent can rapidly polymerize to form a colloid with a high degree of cross-linking structure, thereby achieving bonding with the substrate. Adding amide monomers can improve the bonding strength and pull-out strength of anaerobic adhesives. Due to the polarity and coordination energy of the amide bond in the molecular chain, the affinity of amide monomers to the coated silicon steel sheet is significantly increased, and therefore, the bonding effect of the anaerobic adhesive made is good and the pull-out strength is high. Adding a soluble high molecular weight polymer, i.e., an acrylate oligomer, can improve the peeling force and pull-out force of anaerobic adhesives. Meanwhile, it can also resist high temperature without cracking, maintain high pull-out strength and anti-vibration. Adding a tackifier can further enhance the adhesion of anaerobic adhesives to various substrates. Furthermore, by adding an oxidizable transition metal organic compound reaction accelerator and a phosphorus-containing acrylate monomer to the primer, the adhesion of the anaerobic adhesive to the substrate can be improved, thereby increasing the pull-out force while maintaining the curing speed. Therefore, even in a short period of time, when bonding anaerobic adhesives to iron cores, the curing degree can meet the standard requirements, while also meeting the pull-out force requirements.

[0021] In order to improve the bonding strength, curing time and high temperature resistance when used for bonding silicon steel sheets, the mass ratio of the main agent to the accelerating primer is preferably 1-20:1-20.

[0022] In order to further improve the bonding strength, curing speed and high temperature resistance of the anaerobic adhesive, in one embodiment of the present application, the main agent includes, by weight: 35 to 65 parts of acrylate monomers, 7 to 18 parts of acrylate oligomers, 7 to 18 parts of tackifiers and 3 to 8 parts of amide monomers; the promoting primer includes, by weight: 1 to 20 parts of phosphorus-containing acrylate monomers and 0.01 to 0.8 parts of reaction accelerators.

[0023] In one embodiment of the present application, the mass ratio of the acrylate monomer to the amide monomer in the main agent is 5 to 20:1; and / or the mass ratio of the acrylate oligomer to the tackifier is 0.6 to 2.5:1; and / or, the acrylate monomer is a methacrylate monomer and / or a trifunctional acrylate, wherein the methacrylate monomer is selected from any one or more of glycidyl methacrylate, lauric methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, tetrahydrofuran methacrylate, tetrahydrofuran hydroxypropyl methacrylate, tetraethylene glycol dimethacrylate, ethylene glycol bisphenol A dimethacrylate and hexanediol dimethacrylate; the trifunctional acrylate is selected from trimethylolpropane triacrylate, pentaerythritol triacrylate, (3) ethoxylated trimethylolpropane triacrylate, tris(2-hydroxyethyl)isocyanurate tripropylene glycol ... any one or more of acrylate and (3) propoxylated glycerol triacrylate; and / or, the acrylate oligomer is selected from any one or more of aromatic polyurethane acrylate, aliphatic polyurethane acrylate and epoxy acrylate polymer; preferably, the aromatic polyurethane acrylate is a polymer obtained by prepolymerizing a polyether polyol or a polyester polyol with an aromatic isocyanate (toluene diisocyanate, diphenylmethane diisocyanate) and then capping with a (meth) acrylate hydroxy ester, such as polyethylene glycol ether-TDI-hydroxyethyl dimethacrylate addition polymer and / or polyethylene adipate-MDI-hydroxypropyl dimethacrylate addition polymer; preferably, the aliphatic polyurethane acrylate is a polymer obtained by prepolymerizing a polyester polyol / polyether polyol with an aliphatic isocyanate and then capping with a (meth) acrylate hydroxy ester. The epoxy acrylate polymer is preferably any one or more of bisphenol A epoxy diacrylate, bisphenol A epoxy dimethacrylate, novolac epoxy acrylate, epoxidized oil acrylate, amine-modified epoxy acrylate, fatty acid-modified epoxy acrylate and anhydride-modified epoxy acrylate; and / or the tackifier is selected from any one or more of styrene-butadiene rubber, nitrile-butadiene rubber, resol resin, styrene, chloroprene rubber, MBS resin, ABS resin, polymethacrylate, polyvinylidene chloride and chlorosulfonated polyethylene; And / or, the amide monomer is an unsaturated amide monomer, and the unsaturated amide monomer is a vinylamide compound and / or an acrylamide compound, preferably the vinylamide compound is selected from any one or more of N-vinylsulfonamide, N-vinylcarbonylamide, and N-vinyllactam; wherein the N-vinyllactam compound is selected from any one or more of vinylpyrrolidone, vinylmethylpyrrolidone, vinyl-dimethylpyrrolidone, vinylpiperidone, and vinyl-6-caprolactam; preferably the acrylamide is selected from any one or more of N-acrylsulfonamide, N-acrylcarbonylamide, and N-acryllactam; wherein the N-acryllactam is acryloylmorpholine and / or dimethylacrylamide.

[0024] Controlling the mass ratio and types of acrylate monomers and amide monomers in the base agent within the above range helps the anaerobic adhesive better meet the requirements of high bond strength while maintaining rapid curing. Acrylate monomers provide faster curing speeds, while amide monomers provide higher bond strengths. Therefore, an appropriate mass ratio and types help balance the requirements of rapid curing and high bond strength.

[0025] The preferred mass ratio and type of acrylate oligomer and tackifier are controlled within the above ranges, which helps further improve the bond strength and toughness of the anaerobic adhesive. The acrylate oligomer provides basic bonding performance and a certain degree of toughness, while the tackifier, through its inherent properties, further enhances the adhesive's adhesion to the substrate. The tackifier's elasticity also increases the toughness of the cured adhesive. Therefore, an appropriate mass ratio and type help combine the advantages of the acrylate oligomer and tackifier, thereby achieving higher bond strength and good impact resistance.

[0026] Aromatic polyurethane acrylates offer high bonding strength and good toughness, helping to enhance the impact resistance and peel resistance of anaerobic adhesives. Epoxy acrylates, on the other hand, offer excellent chemical and heat resistance, helping to enhance the stability of anaerobic adhesives in high-temperature and chemically corrosive environments. Furthermore, the reactivity of epoxy groups can provide additional crosslinking points, increasing the cohesive force of the colloid. Therefore, the preferred acrylate oligomer is a combination of aromatic polyurethane acrylate and epoxy acrylate polymers, with a controlled mass ratio of 7-18:7-18. This helps to enhance the synergistic effect of the aromatic polyurethane acrylate and epoxy acrylate polymers, thereby achieving a better balance between the bonding strength, toughness, chemical resistance, and heat resistance of the anaerobic adhesive.

[0027] In one embodiment of the present application, the mass ratio of the phosphorus-containing acrylate monomer to the reaction accelerator in the promoting primer is 0.125 to 2000:1; and / or the phosphorus-containing acrylate monomer is selected from ethylene glycol methacrylate phosphate and / or hydroxyethyl methacrylate phosphate; and / or the reaction accelerator is an organic chelated metal complex, the organic chelated metal complex includes a metal salt and an organic ligand, the metal salt is selected from any one or more of copper salts, iron salts, manganese salts, cobalt salts and nickel salts; the organic ligand is selected from any one or more of acetylacetone, ethyl acetoacetate, methacrylic acid, hexanoic acid and naphthoic acid; preferably, the reaction accelerator is any one or more of ferrocene, copper acetylacetonate and copper ethylhexanoate.

[0028] Preferably, the mass ratio and type of the phosphorus-containing acrylate monomer and the reaction accelerator are controlled within the above ranges, which helps to further improve the adhesion of the anaerobic adhesive to the substrate, thereby better meeting the pull-out force requirements while ensuring the curing speed.

[0029] The preferred phosphorus-containing acrylate monomer is a combination of ethylene glycol methacrylate phosphate and hydroxyethyl methacrylate phosphate, with the mass ratio of ethylene glycol methacrylate phosphate to hydroxyethyl methacrylate phosphate controlled at 0.5-5:0.5-5. This helps form a strong chemical bond with the substrate surface, further improving the bond strength and durability of the anaerobic adhesive. Furthermore, since motors generate significant heat during operation, the combination of ethylene glycol methacrylate phosphate and hydroxyethyl methacrylate phosphate enables the anaerobic adhesive to maintain good bonding and structural stability even in high-temperature environments, making it more suitable for bonding silicon steel sheets in motor cores.

[0030] Furthermore, organic chelate metal complexes are formed by the combination of organic ligands and metal salts via coordination bonds.

[0031] In one embodiment of the present application, the main agent further comprises, by weight, 0.1 to 2 parts of a stabilizer, 0.1 to 10 parts of an initiator, 0.5 to 15 parts of a promoter, and 0.1 to 2 parts of a co-promoter; wherein the stabilizer is selected from any one or more of 2,6-di-tert-butyl-4-methylphenol, hydroquinone, p-benzoquinone, methoxyphenol benzoquinone, 1,4-naphthoquinone, tetrasodium salt of ethylenediaminetetraacetic acid, and disodium ethylenediaminetetraacetic acid; and / or the initiator is selected from any one of cumene hydroperoxide, benzoic acid peroxide, tert-butyl peroxide, tert-butyl benzoate, and benzoyl peroxide. or more; and / or, the accelerator is a nitrogen-containing organic compound and / or a sulfur-containing organic compound, preferably the nitrogen-containing organic compound is selected from any one or more of ethylenediamine, triethylamine, propylenediamine, N-dimethylaniline, triethanolamine, dimethylformamide, dimethyl-p-toluidine, diethyl-p-toluidine, acetophenylhydrazine and aldehyde-amine condensate, preferably the sulfur-containing organic compound is selected from any one or more of tetramethylthiourea, 1-vinyl-2-thiourea, N-acryloylthiourea, p-toluenehydrazone and dodecyl mercaptan; and / or, the co-accelerator is selected from any one or more of o-sulfonylbenzenimide, phenylthiourea and ascorbic acid.

[0032] The type and content of the stabilizer preferably fall within the above-mentioned ranges, helping the anaerobic adhesive maintain its activity and bonding properties even under prolonged storage conditions. The type and content of the initiator preferably fall within the above-mentioned ranges, helping to control the rate of the curing reaction, thereby facilitating rapid curing of the anaerobic adhesive. The type and content of the accelerator and co-accelerator preferably fall within the above-mentioned ranges, helping to accelerate the curing reaction of the anaerobic adhesive, thereby achieving faster curing under specified operating conditions, such as when bonding silicon steel laminations for motor cores, thereby shortening production cycles and improving production efficiency.

[0033] In one embodiment of the present application, the primer further comprises 10 to 90 parts by weight of an organic solvent; wherein the organic solvent is selected from any one or more of ethanol, isopropanol, ethyl acetate and acetone.

[0034] The type and content of the organic solvent in the accelerating primer are preferably within the above ranges, which helps to better disperse the functional monomer and the reaction accelerator in the organic solution, thereby improving the uniformity of the accelerating primer.

[0035] In another typical embodiment of the present application, an anaerobic adhesive is provided, which is obtained by mixing an anaerobic adhesive composition, and the anaerobic adhesive composition is the above-mentioned anaerobic adhesive composition.

[0036] The anaerobic adhesive obtained by mixing the above-mentioned anaerobic adhesive composition has good bonding strength, curing speed and high temperature resistance. In addition, the anaerobic adhesive is used to perform preliminary bonding and positioning of the electronic chip, and the curing degree of the anaerobic adhesive can reach the standard within a short period of time (the initial curing time is within 3 minutes, preferably 0.5 to 2 minutes) and meet the requirements of the pull-out force. In the application process of the motor core, the anaerobic adhesive of the present application can resist high temperatures without cracking, maintain high pull-out strength, anti-vibration and good oil resistance and stability.

[0037] In another typical embodiment of the present application, a method for preparing the above-mentioned anaerobic adhesive is provided, which comprises: step S1, mixing raw materials including acrylate monomers, acrylate oligomers, tackifiers, and amide monomers to obtain a main agent; and step S2, mixing raw materials including phosphorus-containing acrylate monomers and reaction accelerators to obtain a promoter primer; wherein the anaerobic adhesive comprises a main agent and a promoter primer.

[0038] The present application obtains a main agent and a promoting primer respectively by the above-mentioned preparation method and forms an anaerobic adhesive. Not only can the curing degree of the anaerobic adhesive reach the standard in a short time (within 3 minutes), but also can achieve higher pull-out strength and excellent failure form, thereby meeting the bonding requirements of the motor core silicon steel sheet, but also has the advantages of resisting high temperature without cracking, maintaining high pull-out strength, anti-vibration and good oil-resistant stability. Specifically, on the one hand, adding an acrylate monomer in the main agent can rapidly polymerize to form a colloid with a highly cross-linked structure, thereby achieving bonding with the substrate. Adding an amide monomer can improve the bonding strength and pull-out strength of the anaerobic adhesive. Adding an acrylate oligomer can improve the peeling force and pull-out force of the anaerobic adhesive. Adding a tackifier can further improve the adhesion performance of the anaerobic adhesive to different substrates. On the other hand, by adding a reaction accelerator and a phosphorus-containing acrylate monomer in the promoting primer, the adhesion of the anaerobic adhesive to the substrate can be improved, thereby improving the pull-out force while ensuring the curing speed.

[0039] In one embodiment of the present application, the above-mentioned step S1 also includes: step S11, performing a first mixing of the raw materials including the acrylate monomer, the acrylate polymer and the tackifier to obtain a first mixture; step S22, performing a second mixing of the raw materials including the first mixture, the stabilizer, the accelerator, the co-accelerator and the initiator to obtain a second mixture; step S23, performing a third mixing of the raw materials including the second mixture and the amide monomer to obtain a main agent; wherein, the rotation speed of the first mixing is 200~800rpm, and the time of the first mixing is 3~8h; and / or, the rotation speed of the second mixing is 300~900rpm, and the time of the second mixing is 2~6h; and / or, the rotation speed of the third mixing is 300~600rpm, and the time of the third mixing is 0.5~1h.

[0040] Step S11 facilitates the thorough mixing of the acrylate monomer, acrylate oligomer, and tackifier to obtain a uniform liquid, thereby ensuring the realization of mechanical properties. Step S22 further facilitates the uniform dispersion of the first mixture with the stabilizer, accelerator, co-accelerator, and initiator, thereby ensuring the storage stability of the glue and rapid curing during reaction. Step S23 further facilitates the uniform mixing of the amide monomers, thereby achieving high adhesion of the glue to the substrate during bonding.

[0041] In one embodiment of the present application, the above-mentioned step S2 also includes: performing a fourth mixing of the raw materials including the phosphorus-containing acrylate monomer, the reaction accelerator and the organic solvent to obtain a promoting primer; wherein the rotation speed of the fourth mixing is 50 to 200 rpm, and the time of the fourth mixing is 2 to 6 hours.

[0042] Preferably, by subjecting the raw materials comprising the phosphorus-containing acrylate monomer, reaction accelerator, and organic solvent to a fourth mixing step, and controlling the speed and duration of the fourth mixing step within the aforementioned ranges, the phosphorus-containing acrylate monomer and reaction accelerator are better dispersed in the organic solution, thereby improving the uniformity of the accelerator primer. Furthermore, the addition of the reaction accelerator and phosphorus-containing acrylate to the accelerator primer further improves the adhesion of the anaerobic adhesive to the substrate, thereby increasing the pull-out strength while maintaining a high cure speed.

[0043] The beneficial effects of the present application will be further illustrated below with reference to embodiments.

[0044] Example 1

[0045] Anaerobic adhesive includes a main agent and a accelerator, and the mass ratio of the main agent to the accelerator is 1:1.

[0046] Preparation of the main agent: 44.7 parts of the acrylic acid ester monomer isobornyl methacrylate, 5 parts of the acrylic acid ester monomer hydroxyethyl methacrylate, 10 parts of the acrylic acid ester oligomer bisphenol A epoxy ester, and 5 parts of the tackifier styrene-butadiene rubber were added to a reaction kettle and mixed for 5 hours at 400 rpm until the styrene-butadiene rubber was completely dissolved, thereby obtaining a first mixture. 0.05 parts of the stabilizer ethylenediaminetetraacetic acid tetrasodium salt (EDTA-4Na salt), 0.05 parts of the stabilizer p-benzoquinone, 0.5 parts of the co-accelerator o-sulfonylbenzene imide (saccharin), 0.5 parts of the accelerator acetophenylhydrazine, and 1 part of the initiator cumene hydroperoxide were added to the first mixture in sequence and mixed for 1 hour at 600 rpm to obtain a second mixture. The second mixture was then mixed with 5 parts of the amide monomer vinyl pyrrolidone at 400 rpm for 1 hour to obtain the main agent.

[0047] Preparation of the accelerator primer: Calculate the raw materials by weight, and mix 0.1 parts of phosphorus-containing acrylate monomer monosubstituted hydroxyethyl methacrylate phosphate, 0.05 parts of reaction accelerator copper acetylacetonate and 99.85 parts of organic solvent ethanol at 60 rpm for 4 hours to obtain the accelerator primer.

[0048] Example 2

[0049] Anaerobic adhesive includes a main agent and a accelerator, and the mass ratio of the main agent to the accelerator is 1:3.

[0050] Preparation of the main agent: 44.7 parts of the acrylic acid ester monomer isobornyl methacrylate, 5 parts of the acrylic acid ester monomer hydroxyethyl methacrylate, 10 parts of the acrylic acid ester oligomer bisphenol A epoxy dimethacrylate, and 5 parts of the tackifier chlorosulfonated polyethylene were added to a reactor and mixed at 400 rpm for 5 hours until the chlorosulfonated polyethylene was completely dissolved, thereby obtaining a first mixture. 0.05 parts of the stabilizer ethylenediaminetetraacetic acid tetrasodium salt (EDTA-4Na salt), 0.05 parts of the stabilizer p-benzoquinone, 0.5 parts of the co-accelerator ascorbic acid, 0.5 parts of the accelerator tetramethylthiourea, and 1 part of the initiator cumene hydroperoxide were added to the first mixture in sequence and mixed at 600 rpm for 1 hour to obtain a second mixture. The second mixture was then mixed with 3 parts of the amide monomer dimethylacrylamide at 400 rpm for 1 hour to obtain the main agent.

[0051] Preparation of the accelerator primer: Calculate the raw materials by weight, and mix 0.2 parts of phosphorus-containing acrylate monomer trisubstituted hydroxyethyl methacrylate phosphate, 0.05 parts of reaction accelerator copper ethylhexanoate and 99.75 parts of organic solvent ethanol at 60 rpm for 4 hours to obtain the accelerator primer.

[0052] Example 3

[0053] Anaerobic adhesive includes a main agent and a accelerator, and the mass ratio of the main agent to the accelerator is 3:1.

[0054] Preparation of the main agent: 44.7 parts of the acrylic acid ester monomer isobornyl methacrylate, 5 parts of the acrylic acid ester monomer hydroxyethyl methacrylate, 10 parts of the acrylic acid ester oligomer polyethylene glycol ether-TDI-hydroxyethyl dimethacrylate addition polymer, and 5 parts of the tackifier chloroprene rubber were added to a reactor and mixed at 300 rpm for 5 hours until the chloroprene rubber was completely dissolved, thereby obtaining a first mixture. 0.05 parts of the stabilizer ethylenediaminetetraacetic acid tetrasodium salt (EDTA-4Na salt), 0.05 parts of the stabilizer 1,4-naphthoquinone, 0.5 parts of the co-accelerator o-sulfonylbenzene imide (saccharin), 0.5 parts of the accelerator N,N-dimethyl-p-toluidine, and 1 part of the initiator cumene hydroperoxide were added to the first mixture in sequence and mixed at 500 rpm for 1 hour, thereby obtaining a second mixture. The second mixture and 5 parts of amide monomer vinyl-6-caprolactam were mixed for a third time at a rotation speed of 500 rpm for 1 hour to obtain a main agent.

[0055] Preparation of the accelerator primer: Calculate the raw materials by weight, and mix 0.2 parts of the phosphorus-containing acrylate monomer ethylene glycol methacrylate phosphate, 0.05 parts of the reaction accelerator ferrocene and 99.75 parts of the organic solvent ethanol at 80 rpm for 4 hours to obtain the accelerator primer.

[0056] Example 4

[0057] The difference from Example 1 is that the mass ratio of the total mass of the acrylic acid ester monomer (isobornyl methacrylate and acrylic acid ester monomer hydroxyethyl methacrylate) and the amide monomer vinyl pyrrolidone is 47:7.7, among which the weight ratio of isobornyl methacrylate is 22 parts, the weight ratio of hydroxyethyl methacrylate is 25 parts, and the weight ratio of vinyl pyrrolidone is 7.7 parts, and finally the main agent and anaerobic adhesive are obtained.

[0058] Example 5

[0059] The difference from Example 1 is that the mass ratio of the total mass of the acrylate monomers (isobornyl methacrylate and acrylate monomer hydroxyethyl methacrylate) and the amide monomer vinyl pyrrolidone is 44.7:10, among which the weight ratio of isobornyl methacrylate is 15 parts, the weight ratio of hydroxyethyl methacrylate is 29.7 parts, and the weight ratio of vinyl pyrrolidone is 10 parts, and finally the main agent and anaerobic adhesive are obtained.

[0060] Example 6

[0061] The difference from Example 1 is that the mass ratio of the acrylate oligomer bisphenol A epoxy diacrylate and the tackifier styrene butadiene rubber is 1:1, wherein the weight proportion of bisphenol A epoxy diacrylate is 7.5 parts and the weight proportion of styrene butadiene rubber is 7.5 parts, and finally the main agent and anaerobic adhesive are obtained.

[0062] Example 7

[0063] The difference from Example 1 is that the mass ratio of the acrylate oligomer bisphenol A epoxy diacrylate and the tackifier styrene butadiene rubber is 0.5:1, wherein the weight proportion of bisphenol A epoxy diacrylate is 5 parts and the weight proportion of styrene butadiene rubber is 10 parts, and finally the main agent and anaerobic adhesive are obtained.

[0064] Example 8

[0065] The difference from Example 1 is that the mass ratio of the phosphorus-containing acrylate monomer monosubstituted hydroxyethyl methacrylate phosphate and the reaction accelerator copper acetylacetonate is 2:1, wherein the weight portion of monosubstituted hydroxyethyl methacrylate phosphate is 0.1 parts and the weight portion of copper acetylacetonate is 0.05 parts, and finally a promoting primer and anaerobic adhesive are obtained.

[0066] Example 9

[0067] The difference from Example 1 is that the mass ratio of the phosphorus-containing acrylate monomer monosubstituted hydroxyethyl methacrylate phosphate and the reaction accelerator copper acetylacetonate is 1:14, wherein the weight portion of monosubstituted hydroxyethyl methacrylate phosphate is 0.01 parts and the weight portion of copper acetylacetonate is 0.14 parts, and finally a promoting primer and anaerobic adhesive are obtained.

[0068] Example 10

[0069] The difference from Example 1 is that the acrylate oligomer is a combination of polyethylene glycol ether-TDI-hydroxyethyl dimethacrylate addition polymer and bisphenol A epoxy diacrylate, and the mass ratio of polyethylene glycol ether-TDI-hydroxyethyl dimethacrylate addition polymer and bisphenol A epoxy diacrylate is 7:7, and finally the main agent and anaerobic adhesive are obtained.

[0070] Example 11

[0071] The difference from Example 1 is that the acrylate oligomer is a combination of polyethylene glycol ether-TDI-hydroxyethyl dimethacrylate addition polymer and bisphenol A epoxy diacrylate, and the mass ratio of polyethylene glycol ether-TDI-hydroxyethyl dimethacrylate addition polymer and bisphenol A epoxy diacrylate is 1:9, and the main agent and anaerobic adhesive are finally obtained.

[0072] Example 12

[0073] The difference from Example 1 is that the phosphorus-containing acrylate monomer is a combination of ethylene glycol methacrylate phosphate and hydroxyethyl methacrylate phosphate, and the mass ratio of ethylene glycol methacrylate phosphate and hydroxyethyl methacrylate phosphate is 0.5:0.5, and finally a primer and anaerobic adhesive are obtained.

[0074] Example 13

[0075] The difference from Example 1 is that the phosphorus-containing acrylate monomer is a combination of ethylene glycol methacrylate phosphate and hydroxyethyl methacrylate phosphate, and the mass ratio of ethylene glycol methacrylate phosphate to hydroxyethyl methacrylate phosphate is 0.5:6, and finally a primer and anaerobic adhesive are obtained.

[0076] Comparative Example 1

[0077] The difference from Example 1 is that the main agent is prepared as follows: 67.4 parts of the acrylic acid ester monomer isobornyl methacrylate and 30 parts of the polyurethane acrylic resin are added to a reactor and mixed at 400 rpm for 1 hour to obtain a first mixture. 0.05 parts of the stabilizer 1,4-naphthoquinone and 0.05 parts of the stabilizer ethylenediaminetetraacetic acid tetrasodium salt (EDTA-4Na salt) are added to the first mixture in sequence and stirred for 1 hour. Then, 1 part of the co-accelerator o-sulfonylbenzene imide (saccharin), 0.5 parts of the accelerator N,N-dimethyl-p-toluidine, and 1 part of the initiator cumene hydroperoxide are added in sequence and mixed at 600 rpm for 1 hour to obtain the main agent.

[0078] Preparation of the accelerating primer: Calculate the raw materials by weight, and mix 0.05 parts of the reaction accelerator copper acetylacetonate and 99.95 parts of the organic solvent ethanol at a rotation speed of 80 rpm for 4 hours to obtain the accelerating primer.

[0079] Comparative Example 2

[0080] The difference from Example 1 is that the anaerobic adhesive is a single-component anaerobic adhesive, which is composed of 100 parts by weight of hydroxyethyl methacrylate, 3 parts by weight of initiator hydroxyisopropylbenzene peroxide, and 3 parts by weight of accelerator acetophenylhydrazine.

[0081] Test method:

[0082] 1. Pull-out strength test: Cut the silicon steel sheet substrate into a size of 25mm*25mm, apply the accelerator primer of the above embodiment and comparative example on one side, and apply the main agent of the above embodiment and comparative example on the other side. After the accelerator primer is dried, the two test pieces are bonded together. After standing for the specified time (3 minutes, 1 hour and 24 hours) under standard conditions (23°C), the strength required to vertically pull the two test pieces apart is tested.

[0083] 2. Initial consolidation time test: The time required for the tensile strength to reach 0.03 MPa is counted as the initial consolidation time.

[0084] 3. Heat aging performance: After the sample is prepared and allowed to stand for 24 hours in accordance with the above tensile strength test, the bonded test piece is placed in an oven at 180°C for 1000 hours. After cooling to room temperature, the strength is tested according to the method in the above tensile strength test.

[0085] 4. Oil resistance: After the sample is prepared and allowed to stand for 24 hours in accordance with the above pull-out strength test, the bonded test piece is immersed in ATF oil and placed in an oven at 180°C for 1000 hours. After cooling to room temperature, the strength is tested according to the method in the above pull-out strength test.

[0086] The above test results are shown in Table 1.

[0087] Table 1

[0088]

[0089] The failure form between the anaerobic adhesive and the substrate can be observed in the pull-out strength test. As shown in Table 1, the failure form of the embodiment of the present application is cohesive failure, indicating that the anaerobic adhesive of the present application has good adhesion to the substrate, while the failure form of the comparative example 1 is interfacial failure, indicating that the anaerobic adhesive of the comparative example 1 has poor adhesion to the substrate.

[0090] From the above description, it can be seen that the above embodiments of the present invention achieve the following technical effects:

[0091] The present application optimizes the composition and content of the main agent and the promoting primer in the anaerobic adhesive composition in the above range, not only can the curing degree of the anaerobic adhesive reach the standard and realize higher pull-out strength and excellent failure form in a short time (within 3min), thereby meeting the bonding requirements of the motor core silicon steel sheet, but also can make the anaerobic adhesive have the advantages of resisting high temperature without cracking, maintaining high pull-out strength, anti-vibration and good oil-resistant stability. Specifically, on the one hand, adding acrylate monomers in the main agent can rapidly polymerize to form a colloid with a high degree of cross-linking structure, thereby achieving bonding with the substrate. Adding amide monomers can improve the bonding strength and pull-out strength of anaerobic adhesives. Due to the polarity and coordination energy of the amide bond in the molecular chain, the affinity of amide monomers to the coated silicon steel sheet is significantly increased, and therefore, the bonding effect of the anaerobic adhesive made is good and the pull-out strength is high. Adding a soluble high molecular weight polymer, i.e., an acrylate oligomer, can improve the peeling force and pull-out force of anaerobic adhesives. Meanwhile, it can also resist high temperature without cracking, maintain high pull-out strength and anti-vibration. Adding a tackifier can further enhance the adhesion of anaerobic adhesives to various substrates. Furthermore, by adding an oxidizable transition metal organic compound reaction accelerator and a phosphorus-containing acrylate monomer to the primer, the adhesion of the anaerobic adhesive to the substrate can be improved, thereby increasing the pull-out force while maintaining the curing speed. Therefore, even in a short period of time, when bonding anaerobic adhesives to iron cores, the curing degree can meet the standard requirements, while also meeting the pull-out force requirements.

[0092] The above are merely embodiments of the present invention and are not intended to limit the present invention. Those skilled in the art will readily appreciate that the present invention is susceptible to various modifications and variations. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. An anaerobic adhesive composition comprising a main agent and a primer, characterized in that: In parts by weight, the main agent includes: 30-70 parts of acrylic acid ester monomer; 5 to 20 parts of acrylate oligomer; 5 to 20 parts of a tackifier; and 1 to 10 parts of amide monomer; In parts by weight, the accelerating primer comprises: 0.01 to 30 parts of a phosphorus-containing acrylate monomer; and 0.001 to 1 part of a reaction accelerator; Wherein, the reaction accelerator is an organic compound containing transition metal.

2. The anaerobic adhesive composition according to claim 1, characterized in that In parts by weight, the main agent includes: 35 to 65 parts of the acrylic acid ester monomer; 7 to 18 parts of the acrylate oligomer; 7 to 18 parts of the tackifier; and 3 to 8 parts of the amide monomer; In parts by weight, the accelerating primer comprises: 0.1 to 20 parts of the phosphorus-containing acrylate monomer; and 0.01 to 0.8 parts of the reaction accelerator.

3. The anaerobic adhesive composition according to claim 1 or 2, characterized in that The mass ratio of the acrylic acid ester monomer to the amide monomer in the main agent is 5 to 20:1; and / or the mass ratio of the acrylic acid ester oligomer to the tackifier is 0.6 to 2.5:1; And / or, the acrylate monomer is a methacrylate monomer and / or a trifunctional acrylate, wherein the methacrylate monomer is selected from any one or more of glycidyl methacrylate, laurate methacrylate, hydroxyethyl methacrylate, hydroxypropyl methacrylate, isobornyl methacrylate, cyclohexyl methacrylate, tetrahydrofuran methacrylate, tetrahydrofuran hydroxypropyl methacrylate, tetraethylene glycol dimethacrylate, ethylene glycol bisphenol A dimethacrylate and hexanediol dimethacrylate; the trifunctional acrylate is selected from any one or more of trimethylolpropane triacrylate, pentaerythritol triacrylate, (3) ethoxylated trimethylolpropane triacrylate, tris(2-hydroxyethyl)isocyanurate triacrylate and (3) propoxylated glycerol triacrylate; And / or, the acrylate oligomer is selected from any one or more of aromatic polyurethane acrylate, aliphatic polyurethane acrylate and epoxy acrylate polymers; and / or, the tackifier is selected from any one or more of styrene-butadiene rubber, nitrile-butadiene rubber, resol resin, styrene, chloroprene rubber, MBS resin, ABS resin, polymethacrylate, polyvinylidene chloride and chlorosulfonated polyethylene; And / or, the amide monomer is an unsaturated amide monomer, and the unsaturated amide monomer is a vinylamide compound and / or an acrylamide compound, preferably, the vinylamide compound is selected from any one or more of N-vinylsulfonamide, N-vinylcarbonylamide and N-vinyllactam; preferably, the acrylamide compound is selected from any one or more of N-acrylsulfonamide, N-acrylcarbonylamide and N-acryllactam.

4. The anaerobic adhesive composition according to any one of claims 1 to 3, characterized in that The mass ratio of the phosphorus-containing acrylate monomer to the reaction accelerator in the accelerating primer is 0.125 to 2000:1; and / or, the phosphorus-containing acrylate monomer is selected from ethylene glycol methacrylate phosphate and / or hydroxyethyl methacrylate phosphate; And / or, the reaction accelerator is an organic chelated metal complex, which includes a metal salt and an organic ligand, wherein the metal salt is selected from any one or more of copper salts, iron salts, manganese salts, cobalt salts and nickel salts; the organic ligand is selected from any one or more of acetylacetone, ethyl acetoacetate, methacrylic acid, hexanoic acid and naphthoic acid; preferably, the reaction accelerator is any one or more of ferrocene, copper acetylacetonate and copper ethylhexanoate.

5. The anaerobic adhesive composition according to any one of claims 1 to 4, characterized in that In parts by weight, the main agent further comprises: 0.1 to 2 parts of a stabilizer, 0.1 to 10 parts of an initiator, 0.5 to 15 parts of an accelerator, and 0.1 to 2 parts of an auxiliary accelerator.

6. The anaerobic adhesive composition according to any one of claims 1 to 5, characterized in that The accelerating primer further comprises 10 to 90 parts of an organic solvent in parts by weight.

7. An anaerobic adhesive obtained by mixing an anaerobic adhesive composition, characterized in that: The anaerobic adhesive composition is the anaerobic adhesive composition according to any one of claims 1 to 6.

8. A method for preparing the anaerobic adhesive according to claim 7, characterized in that: The preparation method comprises: Step S1, mixing raw materials including acrylate monomers, acrylate oligomers, tackifiers, and amide monomers to obtain a main agent; Step S2, mixing raw materials including a phosphorus-containing acrylate monomer and a reaction accelerator to obtain a accelerator primer; Wherein, the anaerobic adhesive includes the main agent and the accelerating primer.

9. The preparation method according to claim 8, characterized in that The step S1 further includes: Step S11, performing a first mixing of raw materials including the acrylic ester monomer, the acrylic ester oligomer, and the tackifier to obtain a first mixture; Step S22, performing a second mixing of the raw materials including the first mixture, stabilizer, accelerator, co-accelerator and initiator to obtain a second mixture; Step S23, performing a third mixing of the raw materials including the second mixture and the amide monomer to obtain the main agent; wherein the first mixing speed is 200 to 800 rpm, and the first mixing time is 3 to 8 hours; and / or, the second mixing speed is 300 to 900 rpm, and the second mixing time is 2 to 6 hours; And / or, the rotation speed of the third mixing is 300-600 rpm, and the time of the third mixing is 0.5-1 hour.

10. The preparation method according to claim 8 or 9, characterized in that: The step S2 further comprises: performing a fourth mixing of the raw materials including the phosphorus-containing acrylate monomer, the reaction accelerator and the organic solvent to obtain the accelerating primer; Wherein, the rotation speed of the fourth mixing is 50-200 rpm, and the time of the fourth mixing is 2-6 hours.

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