阅读说明：本技术 丙烯酸酯结构胶 (Acrylate structural adhesive ) 是由 甘志勇 高瀚文 杜美娜 于 2018-08-09 设计创作，主要内容包括：本发明提供了一种丙烯酸酯结构胶。该结构胶包括丙烯酸酯类单体、氧化剂、增韧剂、还原剂、钒络合物固化促进剂及附着力促进剂,钒络合物固化促进剂包括式I和/或式II所示结构的化合物。该钒络合物固化促进剂具有良好的溶解性和稳定性,有效改善了丙烯酸酯结构胶的稳定性,且对于丙烯酸酯类单体的快速固化有良好的促进作用。除此以外,使用该钒络合物固化促进剂,配合使用增韧剂和附着力促进剂,使得本发明提供的丙烯酸酯结构胶还具有良好的粘结强度,且由于该结构胶中未采用低沸点物质,使得其具有低气味的特性。(The invention provides an acrylate structural adhesive. The structural adhesive comprises an acrylate monomer, an oxidant, a toughening agent, a reducing agent, a vanadium complex curing accelerator and an adhesion promoter, wherein the vanadium complex curing accelerator comprises a compound with a structure shown in a formula I and/or a formula II. The vanadium complex curing accelerator has good solubility and stability, effectively improves the stability of acrylate structural adhesive, and has good accelerating effect on the rapid curing of acrylate monomers. In addition, the vanadium complex curing accelerator is used, and the toughening agent and the adhesion promoter are matched, so that the acrylate structural adhesive provided by the invention has good bonding strength, and the structural adhesive has the characteristic of low odor because a low-boiling-point substance is not adopted.)

1. The acrylate structural adhesive is characterized by comprising an acrylate monomer, an oxidant, a flexibilizer, a reducing agent, a vanadium complex curing accelerator and an adhesion promoter, wherein the vanadium complex curing accelerator comprises a compound with a structure shown in a formula I and/or a formula II:

G∶V(R₁)_nformula I

G∶(VO)(R₂)_mFormula II

G is a ligand compound and represents a coordination bond, wherein in the formula I, n is an integer of 1-3, and V shows positive trivalent and is connected with n R through an ionic bond and/or a covalent bond₁Connecting; in the formula II, m is 1 or 2, V shows positive quadrivalence and is connected with m R through ionic bond and/or covalent bond₂Connecting; wherein n of said R₁Each independently comprises an anion or electron-withdrawing group in the product formed by oxidizing the reducing substance, m of the R₂The reducing substances are respectively and independently included in anions or electron-withdrawing groups in products formed after the reducing substances are oxidized, and the reducing substances can perform oxidation-reduction reaction with the vanadium with the positive pentavalent state.

2. The acrylate structural adhesive according to claim 1, wherein the reducing substance comprises one or more of an inorganic salt reducing substance, an aldehyde reducing substance, an alcohol reducing substance, an amine reducing substance, a phenol reducing substance, an imidazole reducing substance, and a thiourea reducing substance; preferably, the inorganic salt reducing substance comprises one or more of sulfite, hypochlorite and transition metal salt; preferably, the aldehyde reducing substance comprises one or more of substituted or unsubstituted alkyl aldehydes; preferably, the alcohol reducing substance comprises one or more of substituted or unsubstituted alkyl alcohols; preferably, the amine reducing substance comprises one or more of substituted or unsubstituted alkylamine, substituted or unsubstituted aromatic amine; preferably, the phenolic reducing substance comprises one or more of substituted or unsubstituted phenol; preferably, the imidazole reducing substance comprises 2-methylimidazole and/or 1-acetylimidazole; preferably, the thiourea-based reducing substance includes thiourea and/or tetramethylthiourea.

3. The acrylate structural adhesive of claim 1, wherein the ligand compound comprises a compound comprising one or more of N, P, S and O; preferably, the ligand compound includes one or more of triphenylphosphine, tetramethylthiourea, N-acrylylthiourea, N-benzoylthiourea, 1-allyl-2-thiourea, 1-allyl-3- (2-hydroxyethyl) -2-thiourea, diphenylthiocarbazone, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-vinylimidazole, diethylenetriamine, N' -tetramethyl-1, 6-hexanediamine, N-dimethylbenzylamine, 1-acetylpiperidine, 1-benzoyl-4-piperidone, pentamethyldiethylenetriamine and tetrakis [ (2-pyridyl) methyl ] ethylenediamine.

4. The acrylate structural adhesive according to any one of claims 1 to 3, wherein the vanadium complex cure accelerator further comprises an organic solvent, preferably the organic solvent comprises one or more of dibutyl phthalate, dioctyl phthalate, tributyl phosphate, trioctyl phosphate, triisooctyl phosphate and diisooctyl phosphate;

preferably, the vanadium complex curing accelerator further comprises a pH regulator, more preferably the pH regulator comprises one or more of hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, formic acid, acetic acid, oxalic acid and citric acid, and further preferably the pH of the vanadium complex curing accelerator is 0-5.

5. The acrylate structural adhesive according to any one of claims 1 to 4, wherein the acrylate monomer comprises a first acrylate monomer and a second acrylate monomer, the first acrylate monomer and the second acrylate monomer are the same or different, the toughening agent comprises a first toughening agent and a second toughening agent, the first toughening agent and the second toughening agent are the same or different;

the acrylate structural adhesive comprises a component A and a component B, wherein the component A comprises 35-75 parts by weight of a first acrylate monomer, 4-10 parts by weight of an oxidant and 13-35 parts by weight of a first toughening agent, the component B comprises 0-75 parts by weight of a second acrylate monomer, 1-6 parts by weight of a reducing agent, 1-6 parts by weight of a vanadium complex curing accelerator, 13-35 parts by weight of a second toughening agent and 2-7 parts by weight of an adhesion promoter, and the weight ratio of the component A to the component B is 1-10: 1.

6. The acrylate structural adhesive of claim 5, wherein said first acrylate monomer and said second acrylate monomer each independently comprise hydroxyethyl methacrylate, hydroxypropyl methacrylate, alkoxylated nonylphenol acrylate, 3,3, 3-trimethylcyclohexane acrylate, cyclic trimethylolpropane formal acrylate, tetrahydrofurfuryl acrylate, stearic acid acrylate, isodecyl acrylate, lauric acid methacrylate, isobornyl acrylate, methoxypolyethylene glycol methacrylate, cyclohexane dimethanol diacrylate, 3-hydroxy-2, 2-dimethylpropyl-3-hydroxy-2, 2-dimethylpropyl diacrylate, propoxylated neopentyl glycol diacrylate, tricyclodecane dimethanol diacrylate, ethylene glycol diacrylate, propylene glycol diacrylate, One or more of tripropylene glycol diacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate and 1 and 3-butanediol dimethacrylate;

preferably, the first toughening agent and the second toughening agent each independently comprise one or more of a block copolymer, core shell particles, neoprene, nitrile rubber, carboxylated nitrile rubber, chlorosulfonated polyethylene, C5 petroleum resin, C5 modified C9 petroleum resin, C9 petroleum resin; preferably, the block copolymer comprises one or more of a polystyrene-b-butadiene-b- (methyl methacrylate) block copolymer, poly (methyl methacrylate) -b-poly (n-butyl acrylate) -b-poly (methyl methacrylate), an MBS resin, an ABS resin, an SBS resin, and an SEBS resin; preferably, the core-shell particles are one or more of butyl acrylate/polymethyl methacrylate core-shell particles, styrene butadiene rubber/poly (methyl methacrylate-acrylonitrile) copolymer core-shell particles and butadiene rubber/poly (methyl methacrylate-glycidyl methacrylate) copolymer core-shell particles;

preferably, the oxidizing agent is a peroxide, more preferably the peroxide comprises benzoyl peroxide, cumene hydroperoxide, di-tert-butyl peroxide, dicumyl peroxide, di (tert-butylperoxy) diisopropylbenzene, 1-di (tert-butylperoxy) -3, 3, 5-trimethylcyclohexane, 1-di (tert-butylperoxy) cyclohexane, ethyl-3, 3-di (tert-butylperoxy) butyrate, diisopropyl-peroxydicarbonate carbonate, tert-butyl-peroxyneodecanoate, tert-amyl-peroxyneodecanoate, tert-butyl-monoperoxy maleate, tert-butyl-peroxybenzoate, tert-butyl-peroxy2-ethylhexanoate, tert-amyl-peroxy1-peroxydicarbonate, or a mixture thereof, Monoisopropyl-mono-tert-butyl-peroxycarbonate, dicyclohexyl-peroxycarbonate, dimyristyl-peroxycarbonate, dicetyl-peroxycarbonate, di (2-ethylhexyl) -peroxycarbonate, tert-butyl-peroxy- (2-ethylhexyl) carbonate or tert-butyl-peroxy3, 5, 5-trimethylhexanoate, one or more of benzoic acid-tert-amyl-peroxyester, acetic acid-tert-butyl-peroxyester, carbonic acid-di (4-tert-butyl-cyclohexyl) -peroxyester, neodecanoic acid-cumene-peroxyester, pivalic acid-tert-amyl-peroxyester and pivalic acid-tert-butyl-peroxyester;

preferably, the reducing agent comprises one or more of tetramethyl thiourea, N-acrylyl thiourea, N-benzoyl thiourea, 1-allyl-2 thiourea, 1-allyl-3- (2-hydroxyethyl) -2 thiourea, diphenyl thiocarbazone, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-vinylimidazole, diethylenetriamine, N, N, N ', N' -tetramethyl-1, 6-hexanediamine, N, N-dimethylbenzylamine, 1-acetylpiperidine, 1-benzoyl-4-piperidone, pentamethyldiethylenetriamine and tetra [ (2-pyridyl) methyl ] ethylenediamine;

preferably, the adhesion promoter is one or more of itaconic anhydride, 4' -oxydiphthalic anhydride and bisphenol-A-dititanic anhydride.

7. The acrylate structural adhesive according to claim 5, wherein the component A and the component B respectively comprise 8-25 parts by weight of solubilizing monomer, 5-15 parts by weight of oligomer and 0.5-5 parts by weight of stabilizer;

preferably, the solubilizing monomer is acryloyl morpholine;

preferably, the oligomer comprises one or more of aliphatic polyurethane acrylate oligomer, aromatic polyurethane acrylate oligomer, polyester acrylate oligomer and epoxy oligomer;

preferably, the stabilizer comprises one or more of 2, 6-di-tert-butyl-p-cresol, 2,6, 6-tetramethylpiperidine oxide, an antioxidant TH-1790, 4-hydroxypiperidinol oxyl, hydroquinone and p-benzoquinone.

8. The acrylate structural adhesive according to claim 7, wherein the component A further comprises 4-10 parts by weight of a filler; preferably, the filler is one or more of montmorillonite, ceramic microspheres, diatomite, attapulgite and white carbon black.

9. The acrylate structural adhesive according to claim 7 or 8, wherein the component B further comprises 1-5 parts by weight of a coupling agent.

10. The acrylate structural adhesive according to claim 9, wherein the coupling agent comprises one or more of bis- (3-triethoxysilylpropyl) amine, bis- (3-trimethoxysilylpropyl) amine, 3-aminopropylmethyldiethoxysilane, triamino-functionalized propyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane.

Technical Field

The invention relates to the field of acrylate adhesives, and particularly relates to an acrylate structural adhesive.

Background

The second-generation acrylate structural adhesive has the advantages of high adhesive force, wide adhesive base materials and the like, develops rapidly in more than 20 years, and is widely applied to the industries of rail transit, automobiles, buildings, wind power and the like. However, the structural adhesive still has some disadvantages, and one important disadvantage is that the structural adhesive has strong odor and severe irritation to human body, which seriously affects the large-scale application of the second generation acrylate structural adhesive. In recent years, with the promotion of environmental regulations and the improvement of safety and environmental awareness of operators, the development of low-odor environment-friendly acrylate structural adhesives mainly comprising high-boiling-point acrylate monomers gradually becomes the market development direction. However, the high boiling point acrylate monomer has the problems of low curing activity and the like, so that the peeling strength and the impact strength of the structural adhesive are affected.

In order to solve the problem of low curing activity of the high-boiling-point acrylate monomer, a curing accelerator needs to be added into the system, wherein the vanadium complex curing accelerator is used in the acrylate structural adhesive in a large amount. However, the vanadium ion accelerator on the market is generally solid and has a single structure, and the direct addition of the vanadium ion accelerator into an acrylic acid structural adhesive system has many problems, such as poor solubility; the storage stability is poor, and the acrylate monomer is easily oxidized or reduced by other substances in the system to initiate the polymerization of the acrylate monomer; low bonding strength after curing, and the like.

Disclosure of Invention

The invention mainly aims to provide an acrylate structural adhesive to solve the problems of poor structural adhesive stability and low bonding strength of the acrylate structural adhesive in the prior art due to the fact that a vanadium ion accelerator is solid.

In order to achieve the above object, according to one aspect of the present invention, there is provided an acrylate structural adhesive, which includes an acrylate monomer, an oxidant, a toughener, a reducing agent, a vanadium complex curing accelerator, and an adhesion promoter, wherein the vanadium complex curing accelerator includes a compound having a structure represented by formula I and/or formula II:

G∶V(R₁)_nformula I

G∶(VO)(R₂)_mFormula II

G is a ligand compound and represents a coordination bond, wherein in the formula I, n is an integer of 1-3, and V shows positive trivalent and is connected with n R through an ionic bond and/or a covalent bond₁Connecting; in the formula II, m is 1 or 2, V shows positive quadrivalence and is connected with m R through ionic bond and/or covalent bond₂Connecting; wherein n R₁Each independently comprising reductionM R in the product formed by oxidizing the substance₂The reducing substances respectively and independently comprise anions or electron-withdrawing groups in products formed after the reducing substances are oxidized, and the reducing substances can perform oxidation-reduction reaction with the vanadium with the positive pentavalent state.

Further, the reducing substance comprises one or more of inorganic salt reducing substances, aldehyde reducing substances, alcohol reducing substances, amine reducing substances, phenol reducing substances, imidazole reducing substances and thiourea reducing substances; preferably, the inorganic salt reducing substance comprises one or more of sulfite, hypochlorite and transition metal salt; preferably, the aldehyde reducing substance comprises one or more of substituted or unsubstituted alkyl aldehydes; preferably, the alcohol reducing substance comprises one or more of substituted or unsubstituted alkyl alcohols; preferably, the amine reducing substance comprises one or more of substituted or unsubstituted alkylamine, substituted or unsubstituted aromatic amine; preferably, the phenolic reducing substance comprises one or more of substituted or unsubstituted phenol; preferably, the imidazole reducing substance comprises 2-methylimidazole and/or 1-acetylimidazole; preferably, the thiourea-based reducing substance comprises thiourea and/or tetramethylthiourea.

Further, ligand compounds include compounds containing one or more of N, P, S and O; preferably, the ligand compound includes one or more of triphenylphosphine, tetramethylthiourea, N-acrylylthiourea, N-benzoylthiourea, 1-allyl-2-thiourea, 1-allyl-3- (2-hydroxyethyl) -2-thiourea, diphenylthiocarbazone, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-vinylimidazole, diethylenetriamine, N, N, N ', N' -tetramethyl-1, 6-hexanediamine, N, N-dimethylbenzylamine, 1-acetylpiperidine, 1-benzoyl-4-piperidone, pentamethyldiethylenetriamine and tetrakis [ (2-pyridyl) methyl ] ethylenediamine.

Further, the vanadium complex curing accelerator also comprises an organic solvent, preferably the organic solvent comprises one or more of dibutyl phthalate, dioctyl phthalate, tributyl phosphate, trioctyl phosphate, triisooctyl phosphate and diisooctyl phosphate; preferably, the vanadium complex curing accelerator further comprises a pH regulator, more preferably the pH regulator comprises one or more of hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, formic acid, acetic acid, oxalic acid and citric acid, and further preferably the pH of the vanadium complex curing accelerator is 0-5.

Further, the acrylate monomers comprise a first acrylate monomer and a second acrylate monomer, the first acrylate monomer and the second acrylate monomer are the same or different, the toughening agent comprises a first toughening agent and a second toughening agent, and the first toughening agent and the second toughening agent are the same or different; the acrylate structural adhesive comprises a component A and a component B, wherein the component A comprises 0-75 parts by weight of a first acrylate monomer, 4-10 parts by weight of an oxidant and 13-35 parts by weight of a first toughening agent, the component B comprises 35-75 parts by weight of a second acrylate monomer, 1-6 parts by weight of a reducing agent, 1-6 parts by weight of a vanadium complex curing accelerator, 13-35 parts by weight of a second toughening agent and 2-7 parts by weight of an adhesion promoter, and the weight ratio of the component A to the component B is 1-10: 1.

Further, the first acrylate monomer and the second acrylate monomer each independently include hydroxyethyl methacrylate, hydroxypropyl methacrylate, alkoxylated nonylphenol acrylate, 3,3, 3-trimethylcyclohexane acrylate, cyclotrimethylolpropane formal acrylate, tetrahydrofurfuryl acrylate, stearic acid acrylate, isodecyl acrylate, lauric acid methacrylate, isobornyl acrylate, methoxypolyethylene glycol methacrylate, cyclohexanedimethanol diacrylate, 3-hydroxy-2, 2-dimethylpropyl-3-hydroxy-2, 2-dimethylpropyl diacrylate, propoxylated neopentyl glycol diacrylate, tricyclodecane dimethanol diacrylate, tripropylene glycol diacrylate, triethylene glycol dimethacrylate, trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, one or more of polyethylene glycol dimethacrylate and 1, 3 butanediol dimethacrylate;

preferably, the first toughening agent and the second toughening agent each independently comprise one or more of a block copolymer, core shell particles, neoprene, nitrile rubber, carboxylated nitrile rubber, chlorosulfonated polyethylene, C5 petroleum resin, C5 modified C9 petroleum resin, C9 petroleum resin; preferably, the block copolymer comprises one or more of polystyrene-b-butadiene-b- (methyl methacrylate) block copolymer, poly (methyl methacrylate) -b-poly (n-butyl acrylate) -b-poly (methyl methacrylate), MBS resin, ABS resin, SBS resin and SEBS resin; preferably, the core-shell particles are one or more of butyl acrylate/polymethyl methacrylate core-shell particles, styrene butadiene rubber/poly (methyl methacrylate-acrylonitrile) copolymer core-shell particles and butadiene rubber/poly (methyl methacrylate-glycidyl methacrylate) copolymer core-shell particles;

preferably, the oxidizing agent is a peroxide, and more preferably the peroxide may include benzoyl peroxide, cumene hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, di (t-butylperoxy) diisopropylbenzene, 1-di (t-butylperoxy) -3, 3, 5-trimethylcyclohexane, 1-di (t-butylperoxy) cyclohexane, ethyl-3, 3-di (t-butylperoxy) butyrate, diisopropyl-peroxydicarbonate carbonate, tert-butyl-peroxyneodecanoate, tert-amyl-peroxyneodecanoate, tert-butyl-monoperoxy maleate, tert-butyl-peroxybenzoate, tert-butyl-peroxy2-ethylhexanoate, tert-amyl peroxy2-ethylhexanoate, or the like, Monoisopropyl-mono-tert-butyl-peroxycarbonate, dicyclohexyl-peroxycarbonate, dimyristyl-peroxycarbonate, dicetyl-peroxycarbonate, di (2-ethylhexyl) -peroxycarbonate, tert-butyl-peroxy- (2-ethylhexyl) carbonate or tert-butyl-peroxy3, 5, 5-trimethylhexanoate, one or more of benzoic acid-tert-amyl-peroxyester, acetic acid-tert-butyl-peroxyester, carbonic acid-di (4-tert-butyl-cyclohexyl) -peroxyester, neodecanoic acid-cumene-peroxyester, pivalic acid-tert-amyl-peroxyester and pivalic acid-tert-butyl-peroxyester;

preferably, the reducing agent comprises one or more of tetramethyl thiourea, N-acrylyl thiourea, N-benzoyl thiourea, 1-allyl-2 thiourea, 1-allyl-3- (2-hydroxyethyl) -2 thiourea, diphenyl thiocarbazone, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-vinylimidazole, diethylenetriamine, N, N, N ', N' -tetramethyl-1, 6-hexanediamine, N, N-dimethylbenzylamine, 1-acetylpiperidine, 1-benzoyl-4-piperidone, pentamethyldiethylenetriamine and tetra [ (2-pyridyl) methyl ] ethylenediamine;

preferably, the adhesion promoter is one or more of itaconic anhydride, 4' -oxydiphthalic anhydride and bisphenol-A-dititanic anhydride.

Further, the component A and the component B respectively comprise 8-25 parts by weight of solubilizing monomer, 5-15 parts by weight of oligomer and 0.5-5 parts by weight of stabilizer; preferably, the solubilizing monomer is acryloyl morpholine; preferably, the oligomer comprises one or more of aliphatic polyurethane acrylate oligomer, aromatic polyurethane acrylate oligomer, polyester acrylate oligomer and epoxy oligomer; preferably, the stabilizer comprises one or more of 2, 6-di-tert-butyl-p-cresol, 2,6, 6-tetramethylpiperidine oxide, an antioxidant TH-1790, 4-hydroxypiperidinol oxyl, hydroquinone and p-benzoquinone.

Further, the component A also comprises 4-10 parts of filler in parts by weight; the preferable filler is one or more of montmorillonite, ceramic microsphere, diatomite, attapulgite and white carbon black.

Further, the component B also comprises 2-7 parts by weight of a coupling agent.

Further, the coupling agent comprises one or more of bis- (3-triethoxysilylpropyl) amine, bis- (3-trimethoxysilylpropyl) amine, 3-aminopropylmethyldiethoxysilane, triamino-functional propyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane.

The invention provides an acrylate structural adhesive which comprises an acrylate monomer, an oxidant, a toughening agent, a reducing agent, a vanadium complex curing accelerator and an adhesion promoter, wherein the vanadium complex curing accelerator comprises a compound with a structure shown in a formula I and/or a formula II. In the vanadium complex curing accelerator, vanadium element in the compound with the structure shown in the formula I and/or the formula II shows positive quadrivalence and positive tervalence, has better solubility compared with vanadium with positive pentavalence, and can be dissolved in an organic solvent to form a liquid vanadium complex curing accelerator. Meanwhile, the vanadium element is connected with the ligand compound in a coordination bond form, so that the stability of the compound can be effectively improved, and the redox reaction of the vanadium under the influence of an external environment can be effectively avoided. Based on the reasons, the vanadium complex curing accelerator has good solubility and stability, effectively improves the stability of the acrylate structural adhesive, and has good accelerating effect on the rapid curing of acrylate monomers. In addition, the vanadium complex curing accelerator is used, and the toughening agent and the adhesion promoter are matched, so that the acrylate structural adhesive provided by the invention has good bonding strength, and the structural adhesive has the characteristic of low odor because a low-boiling-point substance is not adopted.

Detailed Description

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present invention will be described in detail with reference to examples.

The present application is described in further detail below with reference to specific examples, which should not be construed as limiting the scope of the invention as claimed.

As described in the background section, the acrylate structural adhesive in the prior art has the problems of poor structural adhesive stability and low bonding strength because the vanadium ion promoter is in a solid state.

In order to solve the problems, the invention provides an acrylate structural adhesive, which is characterized by comprising an acrylate monomer, an oxidant, a toughening agent, a reducing agent, a vanadium complex curing accelerator and an adhesion promoter, wherein the vanadium complex curing accelerator comprises a compound with a structure shown in a formula I and/or a formula II:

G∶V(R₁)_nformula I

G∶(VO)(R₂)_mFormula II

G is a ligand compound and represents a coordination bond, wherein in the formula I, n is an integer of 1-3, and V shows positive trivalent and is connected with n R through an ionic bond and/or a covalent bond₁Connecting; in the formula II, m is 1 or 2, V shows positive quadrivalence and is bonded through an ionic bondAnd/or covalent bonds to m R₂Connecting; wherein n R₁Each independently comprises an anion or electron-withdrawing group, m R in the product formed by oxidation of the reducing substance₂The reducing substances respectively and independently comprise anions or electron-withdrawing groups in products formed after the reducing substances are oxidized, and the reducing substances can perform oxidation-reduction reaction with the vanadium with the positive pentavalent state.

In the vanadium complex curing accelerator, vanadium element in the compound with the structure shown in the formula I and/or the formula II shows positive quadrivalence and positive tervalence, has better solubility compared with vanadium with positive pentavalence, and can be dissolved in an organic solvent to form a liquid vanadium complex curing accelerator. Meanwhile, the vanadium element is connected with the ligand compound in a coordination bond form, so that the stability of the compound can be effectively improved, and the redox reaction of the vanadium under the influence of an external environment can be effectively avoided. Based on the reasons, the vanadium complex curing accelerator has good solubility and stability, effectively improves the stability of the acrylate structural adhesive, and has good accelerating effect on the rapid curing of acrylate monomers. In addition, the vanadium complex curing accelerator is used, and the toughening agent and the adhesion promoter are matched, so that the acrylate structural adhesive provided by the invention has good bonding strength, and the structural adhesive has the characteristic of low odor because a low-boiling-point substance is not adopted.

It should be noted here that, before the acrylate structural adhesive is used, the oxidizing agent and the reducing agent are separately placed, the oxidizing agent and the vanadium complex curing accelerator are also separately placed, and the other components are mixed and placed, for example, the oxidizing agent and the acrylate monomer may be mixed as one component, the remaining components may be mixed as one component, and all the components may be mixed and then coated and cured when in use.

In addition, when an electron-withdrawing group is bonded to V, V exhibits positive electrification due to the strong electron-withdrawing property of the electron-withdrawing group, and therefore R is not always present₁Whether V is linked to V by an ionic or covalent bond is understood to mean that V exhibits a positive trivalent state. From this it can be understoodN of the formula I₁The total valence of (a) is-3, n is an integer of 1-3, and n R₁May be the same or different, and may be, for example, three of the same or different-1-valent anions or-1-valent electron-withdrawing groups, or a mixture thereof, and may be a-3-valent anion or-3-valent electron-withdrawing group, or may be a-1-valent anion (or-1-valent electron-withdrawing group) and 1-2-valent anion (or-2-valent electron-withdrawing group). When the group connected to VO is an electron-withdrawing group, the VO exhibits positive charge due to the strong electron-withdrawing property of the electron-withdrawing group, so that R is not only a positive charge but also a negative charge₂Whether it is linked to VO by an ionic bond or a covalent bond is understood that VO exhibits a positive divalent state and V in VO exhibits a positive tetravalent state. It can be understood that in formula II, m R are₂Has a total valence of-2, and m is 1 or 2 (in this case R₂The valence Y of (a) varies) such as one-2-valent anion or-2-valent electron withdrawing group, or two identical or different-1-valent anions or-1-valent electron withdrawing groups, or a mixture thereof. As will be appreciated by those skilled in the art.

The reducing substance of the present invention may be any substance that can undergo an oxidation-reduction reaction with vanadium having a positive pentavalent state. In a preferred embodiment, the reducing substance includes, but is not limited to, one or more of inorganic salt reducing substances, aldehyde reducing substances, alcohol reducing substances, amine reducing substances, phenol reducing substances, imidazole reducing substances, and thiourea reducing substances.

Preferably, the inorganic salt reducing substance includes, but is not limited to, one or more of sulfite, hypochlorite and transition metal salt.

Preferably, the aldehyde reducing substance includes, but is not limited to, one or more of substituted or unsubstituted alkyl aldehydes. The substituent of the substituted alkyl aldehyde can be one or more of halogen, phenyl, sulfydryl, sulfonic group, carbonyl and hydroxyl.

Preferably, the alcohol reducing substance includes, but is not limited to, one or more of substituted or unsubstituted alkyl alcohols. The substituent of the substituted alkyl alcohol can be one or more of halogen, phenyl, sulfydryl, sulfonic group, amino, isocyanate and carbonyl.

Preferably, the amine-type reducing substance includes, but is not limited to, one or more of substituted or unsubstituted aromatic amine, substituted or unsubstituted alkylamine. The substituent of the substituted alkylamine or substituted aromatic amine can be one or more of halogen, phenyl, sulfydryl, sulfonic group and carbonyl.

Preferably, the phenolic reducing species include, but are not limited to, one or more of substituted or unsubstituted phenols. The substituent of the substituted phenol can be one or more of halogen, alkyl, keto and amino.

The alkyl group in the above alkyl aldehyde, alkyl alcohol or alkyl amine may be a straight-chain alkyl group, a branched-chain alkyl group or a cyclic alkyl group.

In a preferred embodiment, the sulfite includes, but is not limited to, one or more of sodium sulfite, potassium sulfite, ammonium sulfite, hypochlorite includes, but is not limited to, one or more of sodium hypochlorite, potassium hypochlorite, ammonium hypochlorite, transition metal salts include, but is not limited to, one or more of cuprous chloride, cuprous sulfate, cuprous nitrate, ferrous sulfate, ferrous chloride; the substituted or non-substituted alkyl aldehyde reducing substance at least contains 1 aldehyde group, preferably an alkyl aldehyde reducing substance with the carbon atom number less than or equal to 12, and further preferably one or more of acetaldehyde, propionaldehyde, malonaldehyde, butyraldehyde, succinaldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, glucose, benzaldehyde, phenylacetaldehyde, tolualdehyde and methylacetaldehyde; preferably, the alkyl alcohol reducing substance contains at least one hydroxyl group, preferably an alkyl alcohol reducing substance with less than or equal to 12 carbon atoms, preferably one or more of butanol, isobutanol, butanediol, pentanol, isopentyl glycol, isoamyl alcohol, octanol, isooctanol, benzyl alcohol and dichlorobutanol; preferably, the amine reducing substance contains at least one amine group, preferably aniline and/or butylamine; preferably, the phenolic reducing substance comprises phenol and/or p-tert-butylphenol; preferably, the imidazole reducing substance comprises 2-methylimidazole and/or 1-acetylimidazole; preferably, the thiourea-based reducing substance comprises thiourea and/or tetramethylthiourea.

By the action of the reducing substance, the vanadium with the valence of five in the solid vanadium source can be more easily reduced into the vanadium with the valence of four or three, so that the vanadium can be dissolved in the organic solvent. The corresponding anion after the reduction substance is oxidized can be acid radical ion, alkoxy, imidazole, urea and piperidine electron-withdrawing groups generated after oxidation.

Illustratively, different types of reducing species may undergo one of the following reactions:

the oxidation of the valence-variable metal is from a low valence state to a high valence state, such as cuprous ion to cupric ion, ferrous ion to ferric ion, active metal to high valence metal ion, and the reducing agent corresponds to the above-mentioned R₁And R₂Anions which are oxidation products thereof, such as: after cuprous chloride is oxidized to cupric chloride, R₁And R₂Is chloride ion; the anion containing the valency-changing element is oxidized to a higher anion, e.g. sulfurous acid to sulfuric acid, hypochlorous acid to chloric acid, when R is as defined above₁And R₂Is sulfate or chloride; oxidation of aldehydes to form acids, e.g. acetaldehyde to form acetic acid, in which case R is as defined above₁And R₂Are the corresponding electron withdrawing groups; oxidation of the alcohol to form a ketone or aldehyde or acid, in which case R is as defined above₁And R₂Are the corresponding electron withdrawing groups; the phenols are oxidized to form quinones.

In particular, R in the case where the aldehyde reducing substance, the alcohol reducing substance, the amine reducing substance, the phenol reducing substance, the imidazole reducing substance, and the thiourea reducing substance are oxidized and contain a lone pair of N or O₁And R₂Can also be used as a ligand compound, which is beneficial to further improving the stability of the vanadium complex curing accelerator.

The ligand compound may carry a lone pair of electrons and may be bonded to a V coordinate bond. In a preferred embodiment, the ligand compound comprises a compound comprising one or more of N, P, S and O; preferably one or more of triphenylphosphine, tetramethylthiourea, N-acrylylthiourea, N-benzoylthiourea, 1-allyl-2-thiourea, 1-allyl-3- (2-hydroxyethyl) -2-thiourea, diphenylthiocarbazone, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-vinylimidazole, diethylenetriamine, N, N, N ', N' -tetramethyl-1, 6-hexanediamine, N, N-dimethylbenzylamine, 1-acetylpiperidine, 1-benzoyl-4-piperidone, pentamethyldiethylenetriamine and tetrakis [ (2-pyridyl) methyl ] ethylenediamine. Compared with other ligand compounds, the ligand compound is more favorable for improving the stability and the solubility of the vanadium complex curing accelerator, and the ligand compound and the acrylate monomer have better compatibility, so that the use performance of the acrylate structural adhesive is more favorable for improving.

It should be noted that some compounds such as tetramethylthiourea can be used as both the complex and the reducing substance to perform the oxidation-reduction reaction with the pentavalent vanadium, and both do not conflict with each other.

In a preferred embodiment, the vanadium complex cure accelerator further comprises an organic solvent, preferably the organic solvent comprises one or more of dibutyl phthalate, dioctyl phthalate, tributyl phosphate, trioctyl phosphate, triisooctyl phosphate, and diisooctyl phosphate. The compound with the structure shown in the formula I and/or the formula II is dissolved in an organic solvent to form a liquid vanadium complex curing accelerator, and then the liquid vanadium complex curing accelerator is mixed with other components, so that the formed acrylate structural adhesive has better stability.

Preferably, the vanadium complex curing accelerator further comprises a pH regulator, more preferably the pH regulator comprises one or more of hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, formic acid, acetic acid, oxalic acid and citric acid, and further preferably the pH of the vanadium complex curing accelerator is 0-5. In the above pH regulator, P, N, O in phosphoric acid, nitric acid, formic acid, acetic acid, oxalic acid and citric acid, for example, will also carry lone pair electrons, and can also play a role as a ligand compound in the actual accelerator, thereby being more beneficial to improving the stability of the accelerator and further improving the stability of the structural adhesive.

In a preferred embodiment, the raw materials for preparing the vanadium complex curing accelerator comprise, by weight, 2 to 8 parts of a vanadium source, 35 to 65 parts of an organic solvent, 3 to 10 parts of a reducing substance, and 2 to 10 parts of a ligand compound. The pentavalent vanadium in the vanadium source can be reduced into trivalent positive or tetravalent positive by utilizing the reducing substance, so that the pentavalent vanadium can be dissolved in the organic solvent. The reduced vanadium can be connected with anions in a product obtained by oxidation reaction of a reducing agent through an ionic bond, and can also be connected with electron-withdrawing groups in a product obtained by oxidation reaction of a reducing substance through a covalent bond. The ligand compound can form a coordinate bond with the vanadium element to form the vanadium complex represented by the above formula I and/or II. Based on the reasons, the vanadium complex curing accelerator provided by the invention has good solubility and stability when being applied to an acrylic adhesive, and can effectively improve the curing effect of a structural adhesive and improve the curing speed and the comprehensive performance of a cured coating.

The vanadium source may be any vanadium compound containing vanadium pentavalent. In a preferred embodiment, the vanadium source comprises one or more of sodium metavanadate, vanadium pentoxide, potassium metavanadate, sodium orthovanadate, potassium orthovanadate, sodium pyrovanadate and potassium pyrovanadate.

Preferably, the reducing substance includes one or more of an inorganic salt reducing agent, an aldehyde reducing agent, an alcohol reducing agent, an amine reducing agent, a phenol reducing agent, an imidazole reducing agent, and a thiourea reducing agent. Compared with other reducing substances, the reducing effects of the reducing substances are better. In particular, R in the case where the aldehyde reducing agent, the alcohol reducing agent, the amine reducing agent, the phenol reducing agent, the imidazole reducing agent and the thiourea reducing agent are oxidized and contain a lone pair of N or O₁And R₂And the vanadium complex curing accelerator can also be used as a ligand compound, so that the stability of the vanadium complex curing accelerator is further improved, and the stability of the structural adhesive is further improved.

Preferably, the ligand compound includes one or more of triphenylphosphine, tetramethylthiourea, N-acrylylthiourea, N-benzoylthiourea, 1-allyl-2-thiourea, 1-allyl-3- (2-hydroxyethyl) -2-thiourea, diphenylthiocarbazone, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-vinylimidazole, diethylenetriamine, N, N, N ', N' -tetramethyl-1, 6-hexanediamine, N, N-dimethylbenzylamine, 1-acetylpiperidine, 1-benzoyl-4-piperidone, pentamethyldiethylenetriamine and tetrakis [ (2-pyridyl) methyl ] ethylenediamine; preferably, the organic solvent comprises one or more of dibutyl phthalate, dioctyl phthalate, tributyl phosphate, trioctyl phosphate, triisooctyl phosphate and diisooctyl phosphate. Preferably, the inorganic salt type reducing agent includes, but is not limited to, one or more of sulfite, hypochlorite and transition metal salt. Preferably, the aldehyde reducing agent includes, but is not limited to, one or more of substituted or unsubstituted alkyl aldehydes. The substituent of the substituted alkyl aldehyde can be one or more of halogen, phenyl, sulfydryl, sulfonic group, carbonyl and hydroxyl. Preferably, the alcoholic reducing agent includes, but is not limited to, one or more of a substituted or unsubstituted alkyl alcohol. The substituent of the substituted alkyl alcohol can be one or more of halogen, phenyl, sulfydryl, sulfonic group, amino, isocyanate and carbonyl. Preferably, the amine-based reducing agent includes, but is not limited to, one or more of substituted or unsubstituted aromatic amine, substituted or unsubstituted alkylamine. The substituent of the substituted alkylamine or substituted aromatic amine can be one or more of halogen, phenyl, sulfydryl, sulfonic group and carbonyl. Preferably, the phenolic reducing agent includes, but is not limited to, one or more of substituted or unsubstituted phenols. The substituent of the substituted phenol can be one or more of halogen, alkyl, keto and amino.

The alkyl group in the above alkyl aldehyde, alkyl alcohol or alkyl amine may be a straight-chain alkyl group, a branched-chain alkyl group or a cyclic alkyl group.

In a preferred embodiment, the sulfite includes, but is not limited to, one or more of sodium sulfite, potassium sulfite, ammonium sulfite, hypochlorite includes, but is not limited to, one or more of sodium hypochlorite, potassium hypochlorite, ammonium hypochlorite, transition metal salts include, but is not limited to, one or more of cuprous chloride, cuprous sulfate, cuprous nitrate, ferrous sulfate, ferrous chloride; the substituted or unsubstituted alkyl aldehyde reducing agent at least contains 1 aldehyde group, preferably an alkyl aldehyde reducing agent with the carbon atom number less than or equal to 12, and further preferably one or more of acetaldehyde, propionaldehyde, malonaldehyde, butyraldehyde, succinaldehyde, isobutyraldehyde, valeraldehyde, isovaleraldehyde, glucose, benzaldehyde, phenylacetaldehyde, tolualdehyde and methylphenaldehyde; preferably, the alkyl alcohol reducing agent contains at least one hydroxyl group, preferably an alkyl alcohol reducing agent with the carbon number less than or equal to 12, preferably one or more of butanol, isobutanol, butanediol, pentanol, isopentyl glycol, isoamyl alcohol, octanol, isooctanol, benzyl alcohol and dichlorobutanol; preferably, the amine-based reducing agent contains at least one amine group, preferably aniline and/or butylamine; preferably, the phenolic reducing agent comprises phenol and/or p-tert-butylphenol; preferably, the imidazole-based reducing agent comprises 2-methylimidazole and/or 1-acetylimidazole; preferably, the thiourea-based reducing agent comprises thiourea and/or tetramethylthiourea.

In order to further improve the stability of the vanadium complex accelerator and improve the reaction effect of the reducing agent and the vanadium source, in a preferred embodiment, the raw material of the vanadium complex curing accelerator further comprises 3-10 parts by weight of a pH regulator; preferably, the pH regulator comprises one or more of hydrochloric acid, sulfuric acid, phosphoric acid, nitric acid, formic acid, acetic acid, oxalic acid and citric acid; more preferably, the raw material of the vanadium complex curing accelerator further comprises 30-60 parts of a cosolvent, and the cosolvent is water. The cosolvent is favorable for dissolving in the solid vanadium source organic solvent, and the reaction is promoted.

The preparation method of the vanadium complex accelerator can be as follows: reacting a vanadium source and a reducing substance in an organic solvent to form an intermediate product; and adding a ligand compound into the intermediate product for reaction to obtain the vanadium complex curing accelerator.

The reaction process of each step can be adjusted, and in a preferred embodiment, the step of reacting the vanadium source and the reducing substance in the organic solvent comprises the following steps: mixing a vanadium source, a reducing substance and an organic solvent, and simultaneously adding a pH regulator into the mixture to form a mixture; and reacting the mixture at the temperature of 90-110 ℃ for 1-3h to obtain an intermediate product. This is advantageous in that the reaction between vanadium and the reduced matter proceeds more sufficiently to dissolve it in the organic solvent more sufficiently.

Preferably, after the step of reacting the mixture at the temperature of 90-110 ℃ for 1-3h, the preparation method further comprises the step of adding a cosolvent into a reaction system of the mixture for further reaction for 0.5-1.5h to obtain an intermediate product, wherein the cosolvent is water.

In a preferred embodiment, after the step of adding the ligand compound to the intermediate product to carry out the reaction, the production method further comprises a step of purifying the reaction system, the purification step comprising: carrying out water-oil separation on a reaction system after adding a ligand compound for reaction to obtain an organic phase; and (4) carrying out water removal treatment on the organic phase to obtain the vanadium complex curing accelerator. The water in the vanadium complex curing accelerator can be removed through purification treatment, and a more stable accelerator system is obtained.

As described above, the above acrylate structural adhesive is used before the oxidizing agent and the reducing agent are separately placed, the oxidizing agent and the vanadium complex curing accelerator are also separately placed, and the other components are mixed and placed, for example, the oxidizing agent and the acrylate monomer can be mixed as one component, the remaining components can be mixed as one component, and all the components can be mixed and then coated and cured when in use. In a preferred embodiment, the acrylate monomers include a first acrylate monomer and a second acrylate monomer, the first acrylate monomer and the second acrylate monomer are the same or different, the toughening agent includes a first toughening agent and a second toughening agent, the first toughening agent and the second toughening agent are the same or different; the acrylate structural adhesive comprises a component A and a component B, wherein the component A comprises 35-75 parts by weight of a first acrylate monomer, 4-10 parts by weight of an oxidant and 13-35 parts by weight of a first toughening agent, the component B comprises 0-75 parts by weight of a second acrylate monomer, 1-6 parts by weight of a reducing agent, 1-6 parts by weight of a vanadium complex curing accelerator, 2-7 parts by weight of an adhesion promoter and 13-35 parts by weight of a second toughening agent, and the weight ratio of the component A to the component B is 1: 1-10: 1.

The structural adhesive component is divided into a component A and a component B so as to separate an oxidizing agent, a reducing agent and a curing accelerator. The acrylic monomer and the toughening agent are divided into two parts and placed in the component A and the component B, so that the components can be better mixed to form two components with more suitable viscosity, fluidity and stability, the mixed liquid of the two components is easier and the mixing and dispersing effects of different components are better when the structural adhesive is used, and the use performance of the structural adhesive can be improved. And the dosage relation of each component is controlled in the range, so that the physical and chemical properties of the structural adhesive can be further improved, such as the viscosity, the fluidity and the curing speed are more matched, the dispersibility of each component is better through a coupling agent and the like, the adhesive strength of the adhesive layer after the structural adhesive is cured is higher, and the like.

In the above acrylate structural adhesive, the acrylate monomer may be of a type commonly used in the art. To further improve the overall performance of the structural adhesive, in a preferred embodiment, the first acrylate monomer and the second acrylate monomer each independently comprise hydroxyethyl methacrylate, hydroxypropyl methacrylate, alkoxylated nonylphenol acrylate, 3,3, 3-trimethylcyclohexane acrylate, cyclotrimethylolpropane formal acrylate, tetrahydrofurfuryl acrylate, stearic acid acrylate, isodecyl acrylate, lauric acid methacrylate, isobornyl acrylate, methoxypolyethylene glycol methacrylate, cyclohexanedimethanol diacrylate, 3-hydroxy-2, 2-dimethylpropyl-3-hydroxy-2, 2-dimethylpropyl diacrylate, propoxylated neopentyl glycol diacrylate, tricyclodecane dimethanol diacrylate, poly (ethylene glycol) acrylate, One or more of tripropylene glycol diacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate and 1 and 3-butanediol dimethacrylate. The acrylate monomers have the advantages of high boiling point and good adhesive property, and the structural adhesive formed by matching the vanadium complex curing accelerator has the advantages of lower odor, higher curing speed and better adhesive property.

In a preferred embodiment, the first toughening agent and the second toughening agent each independently comprise one or more of a block copolymer, core shell particles, neoprene, nitrile rubber, carboxylated nitrile rubber, chlorosulfonated polyethylene, C5 petroleum resin, C5 modified C9 petroleum resin, C9 petroleum resin; preferably, the block copolymer comprises one or more of polystyrene-b-butadiene-b- (methyl methacrylate) block copolymer, poly (methyl methacrylate) -b-poly (n-butyl acrylate) -b-poly (methyl methacrylate), MBS resin, ABS resin, SBS resin and SEBS resin; preferably, the core-shell particles are one or more of butyl acrylate/polymethyl methacrylate core-shell particles, styrene butadiene rubber/poly (methyl methacrylate-acrylonitrile) copolymer core-shell particles, and butadiene rubber/poly (methyl methacrylate-glycidyl methacrylate) copolymer core-shell particles. The toughening agents and other components in the structural adhesive have better mixing performance, and the toughening effect is better, so that the bonding performance of the structural adhesive is further improved.

The oxidizing agent and the reducing agent may be those conventionally used in the art. To further enhance the curing and bonding effects of the structural adhesive, in a preferred embodiment, the oxidizing agent is a peroxide, more preferably a peroxide including, but not limited to, benzoyl peroxide, cumene hydroperoxide, di-t-butyl peroxide, dicumyl peroxide, di (t-butylperoxy) diisopropylbenzene, 1-di (t-butylperoxy) -3, 3, 5-trimethylcyclohexane, 1-di (t-butylperoxy) cyclohexane, ethyl-3, 3-di (t-butylperoxy) butyrate, diisopropyl-peroxydiester carbonate, neodecanoic acid-t-butyl-peroxyester, neodecanoic acid-t-amyl-peroxyester, maleic acid-t-butyl-monoperoxyester, benzoic acid-t-butyl-peroxyester, and mixtures thereof, 2-ethylhexanoic acid-tert-butyl-peroxyester, 2-ethylhexanoic acid-tert-amyl-peroxyester, monoisopropyl-mono-tert-butyl-peroxyester carbonate, dicyclohexyl-peroxyester carbonate, dimyristyl-peroxyester carbonate, dicetyl-peroxyester carbonate, di (2-ethylhexyl) -peroxyester carbonate, tert-butyl-peroxy- (2-ethylhexyl) carbonate or 3,5, 5-trimethylhexanoic acid-tert-butyl-peroxyester, benzoic acid-tert-amyl-peroxyester, acetic acid-tert-butyl-peroxyester, di (4-tert-butyl-cyclohexyl) -peroxyester carbonate, neodecanoic acid-cumene-peroxyester, 2-ethylhexanoic acid-tert-amyl-peroxyester, di (2-ethylhexyl) -peroxyester carbonate, di (4-tert-butyl-cyclohexyl, One or more of pivalic acid-tert-amyl-peroxyester and pivalic acid-tert-butyl-peroxyester. Preferably, the reducing agent comprises one or more of tetramethyl thiourea, N-acrylyl thiourea, N-benzoyl thiourea, 1-allyl-2 thiourea, 1-allyl-3- (2-hydroxyethyl) -2 thiourea, diphenyl thiocarbazone, 2-methylimidazole, 2-ethyl-4-methylimidazole, 1-vinylimidazole, diethylenetriamine, N, N, N ', N' -tetramethyl-1, 6-hexanediamine, N, N-dimethylbenzylamine, 1-acetylpiperidine, 1-benzoyl-4-piperidone, pentamethyldiethylenetriamine and tetra [ (2-pyridyl) methyl ] ethylenediamine.

Preferably, the adhesion promoter is one or more of itaconic anhydride, 4' -oxydiphthalic anhydride and bisphenol-A-dititanic anhydride, and the addition of the adhesion promoter is beneficial to further improving the bonding strength of the adhesive to various base materials.

In order to further improve the bonding property, the stability and the coating property of the structural adhesive, in a preferred embodiment, the component A and the component B respectively comprise 8-25 parts by weight of solubilizing monomer, 5-15 parts by weight of oligomer and 0.5-5 parts by weight of stabilizer. Preferably, the solubilizing monomer is acryloyl morpholine; preferably, the oligomer comprises one or more of aliphatic polyurethane acrylate oligomer, aromatic polyurethane acrylate oligomer, polyester acrylate oligomer and epoxy oligomer; preferably, the stabilizer comprises one or more of 2, 6-di-tert-butyl-p-cresol, 2,6, 6-tetramethylpiperidine oxide, an antioxidant TH-1790, 4-hydroxypiperidinol oxyl, hydroquinone and p-benzoquinone.

In a preferred embodiment, the component A further comprises 4-10 parts by weight of filler; the preferable filler is one or more of montmorillonite, ceramic microsphere, diatomite, attapulgite and fumed silica. The addition of the filler is also beneficial to improving the mechanical property of the adhesive layer after the structural adhesive is cured.

In order to further improve the bonding strength of the structural adhesive, in a preferred embodiment, the component B also comprises 1-5 parts of a coupling agent, and the preferred coupling agent comprises one or more of bis- (3-triethoxysilylpropyl) amine, bis- (3-trimethoxysilylpropyl) amine, 3-aminopropylmethyldiethoxysilane, triamino-functionalized propyltrimethoxysilane and 3-mercaptopropyltrimethoxysilane. By using the coupling agent, the compatibility among the components is better, and the stability of the structural adhesive is better.

The invention also provides a method for preparing the acrylate structural adhesive, which is specifically to mix the components according to the formula of the component A and the formula of the component B to prepare the component A and the component B, and then mix the component A and the component B during sizing. The method specifically comprises the following steps:

preparation of component A: putting a first acrylate monomer, an optional solubilizing monomer, an optional oligomer and a first toughening agent into a reaction kettle, and stirring until the first toughening agent is completely dissolved; adding an oxidant, an optional stabilizer and an optional filler into the reaction kettle, stirring for 1-3 hours until the components are uniformly mixed, and removing bubbles in vacuum to obtain a component A;

preparation of the component B: putting a second acrylate monomer, an optional solubilizing monomer, an optional oligomer and a second toughening agent into a reaction kettle, and stirring until the second toughening agent is completely dissolved; then adding a reducing agent and an optional stabilizing agent into the reaction kettle, and stirring for 1-2 hours until the mixture is uniformly mixed; sequentially adding an adhesion promoter, an optional coupling agent and a vanadium complex curing promoter, stirring for 1-3h until the mixture is uniformly mixed, and removing bubbles in vacuum to obtain a component B;

mixing the component A and the component B according to a volume ratio of 1:1, proportioning and sizing.

The beneficial effects of the present invention are further illustrated by the following examples:

< preparation of curing Accelerator for vanadium Complex >