Polycyclic aryl hyperbranched epoxy resin and preparation method and photoluminescent solution, anticorrosive coating and application obtained thereby

Abstract

The present application belongs to the technical field of epoxy resin, and provides a polycyclic aryl hyperbranched epoxy resin and a preparation method thereof.The preparation method comprises the following steps: performing a branched polymerization reaction on a multifunctional epoxy compound and a polycyclic aryl diphenol under the condition of a catalyst to obtain a polycyclic aryl hyperbranched epoxy resin; the mass ratio of the multifunctional epoxy compound, the polycyclic aryl diphenol and the catalyst is 100:20-60:0.01-0.02.The present application further provides a photoluminescence solution and a corrosion-resistant coating containing the resin.The polycyclic aryl hyperbranched epoxy resin of the present application significantly improves the medium resistance and barrier properties of the coating; the polycyclic aryl hyperbranched epoxy resin has intrinsic fluorescence properties, can predict the failure of the steel corrosion-resistant coating, and can be used for the detection of metal ions.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of epoxy resin, in particular to a polycyclic aryl hyperbranched epoxy resin and a preparation method thereof, and a photoluminescence solution, a corrosion-resistant coating and an application obtained by the method. BACKGROUND

[0002] Compared with linear polymers of the same molecular weight, hyperbranched polymers have low viscosity, multifunctionality and high designability, making them widely used in drug carriers, coatings, composite materials and electronic packaging.

[0003] Epoxy resins are widely used in corrosion-resistant coatings and high-performance composites due to their high modulus, high glass transition temperature, low shrinkage, high adhesion and easy processing. However, the network structure with high crosslinking density makes the epoxy cured product have low impact resistance. The lack of toughness greatly limits the application of epoxy resin in fields with higher mechanical performance requirements. Compared with other toughening methods such as rubber particle toughening, engineering plastic toughening and inorganic rigid particle toughening, hyperbranched epoxy resin toughening can achieve toughening effect without loss of glass transition temperature, even with an increase, achieving the effect of simultaneous toughening and strengthening.

[0004] Forecasting the failure of steel protective coating is of great significance for large steel devices such as ships. Since ships are at sea for a long time and the corrosion environment is harsh, the integrity of the ship body is strictly required. When the steel protective coating of the ship body shows visible failure behaviors such as blistering and rusting, the ship body has been corroded for a period of time. If the failure of the steel protective coating can be detected, the safety of life and property can be protected, and the reliability of the ship can be improved. Traditional coatings use pH-responsive color developing agents, fluorescent powders or doped fluorescent molecules in epoxy resins to achieve the effect of forecasting the failure of steel protective coating. However, the color developing agent cannot work in the color paint system, and the fluorescent powder or fluorescent molecule often does not work in a small amount, and in a large amount, it is destructive to the corrosion resistance of the coating.

[0005] Therefore, it is of great value and significance to develop a hyperbranched epoxy resin with enhanced toughness and improved corrosion resistance, and a corrosion-resistant coating for forecasting the failure of steel protective coating. SUMMARY

[0006] The present application aims at providing a polycyclic aryl hyperbranched epoxy resin, a preparation method thereof, and a photoluminescence solution and a corrosion-resistant coating containing the resin to overcome the shortcomings of the prior art.The polycyclic aryl hyperbranched epoxy resin of the present application significantly improves the medium resistance and barrier properties of the coating; the polycyclic aryl hyperbranched epoxy resin has intrinsic fluorescence properties and can predict the failure of steel corrosion-resistant coating; and the polycyclic aryl hyperbranched epoxy resin of the present application can also be used for the detection of metal ions.

[0007] To achieve the above-mentioned application purposes, the present application provides the following technical solutions.

[0008] The present application provides a preparation method of a polycyclic aryl hyperbranched epoxy resin, comprising the following steps:

[0009] The multifunctional epoxy compound and the polycyclic aryl diphenol are subjected to a branched polymerization reaction under the condition of a catalyst to obtain a polycyclic aryl hyperbranched epoxy resin.

[0010] The mass ratio of the multifunctional epoxy compound, the polycyclic aryl diphenol and the catalyst is 100:20-60:0.01-0.02.

[0011] As a preference, the multifunctional epoxy compound comprises one or more of trimethylolpropane triglycidyl ether, glycerol triglycidyl ether, 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester, triphenol methane triglycidyl ether and pentaerythritol tetraglycidyl ether.

[0012] As a preference, the polycyclic aryl diphenol comprises one or more of bisphenol fluorene, 9,9-bis(6-hydroxy-2-naphthol) fluorene, 4,4'-dihydroxydiphenyl, 2,2'-dihydroxydiphenyl, 3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfide, 1,1'-bi-2-naphthol, 2,2-bis-(4-hydroxyphenyl) hexafluoropropane, 4,4'-dihydroxydiphenyl sulfone, bis(4-hydroxyphenyl) phenylphosphine oxide, 4,4'-(1-phenylethyl) bisphenol, 4,4'-dihydroxybenzophenone, 4,4'-benzylidene bisphenol and 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide.

[0013] As a preference, the catalyst comprises one or more of tetrabutylammonium iodide, tetrabutylammonium chloride, tetrabutylammonium bromide, triphenylphosphonium bromide and ethyl triphenylphosphonium chloride.

[0014] As a preference, the temperature of the branched polymerization reaction is 100-180℃, and the time is 2-10h; the branched polymerization reaction is carried out under an inert atmosphere.

[0015] The application further provides the polycyclic aryl hyperbranched epoxy resin prepared by the preparation method.

[0016] The application further provides a photoluminescence solution containing the polycyclic aryl hyperbranched epoxy resin, wherein the photoluminescence solution contains the polycyclic aryl hyperbranched epoxy resin and an organic solvent.

[0017] The mass ratio of the polycyclic aryl hyperbranched epoxy resin and the organic solvent is 0.1-1:50-250.

[0018] The application further provides an application of the photoluminescence solution in metal ion detection.

[0019] The application further provides a hyperbranched epoxy anticorrosive coating containing the polycyclic aryl hyperbranched epoxy resin, which contains component A and component B.

[0020] The component A contains the following components in the following mass parts: the polycyclic aryl hyperbranched epoxy resin 5-50 parts, the bisphenol A type epoxy resin 50-95 parts, the auxiliary agent 0.5-5 parts, and the organic solvent 20-55 parts.

[0021] The component B is an organic amine curing agent.

[0022] The ratio of the epoxy equivalent in the component A and the active hydrogen equivalent in the component B is 1:0.8-1.2.

[0023] The application further provides an application of the hyperbranched epoxy anticorrosive coating in forecasting failure of a steel anticorrosive coating.

[0024] The application has the following beneficial effects:

[0025] 1) The polycyclic aryl structure in the polycyclic aryl hyperbranched epoxy resin has a high-density conjugated double bond, and the molecules are closely packed, which significantly improves the medium resistance and barrier properties of the coating; and the polycyclic aryl hyperbranched epoxy resin has intrinsic fluorescence properties, which can forecast failure of a steel anticorrosive coating.

[0026] 2) The metal ion added in the polycyclic aryl hyperbranched epoxy resin can quench the fluorescence thereof, so that the solution containing the resin can be used for detection of metal ions.

[0027] 3) The preparation method is simple in process and convenient to operate, and is suitable for large-scale industrial production. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 The nuclear magnetic hydrogen spectrum of EHBP1 in Example 1;

[0029] Figure 2 The nuclear magnetic hydrogen spectrum of EHBP2 in Example 2;

[0030] Figure 3 NMR spectrum of EHBP3 of Example 3;

[0031] Figure 4 IR spectra of EHBP1, EHBP2 and EHBP3 of Examples 1-3;

[0032] Figure 5 Fluorescence spectra of different concentrations of EHBP1 / THF solutions at excitation wavelengths of 356 nm and 401 nm, respectively, in which (a) is at an excitation wavelength of 356 nm and (b) is at an excitation wavelength of 401 nm;

[0033] Figure 6 Metal ion response plots of fluorescence spectra of EHBP1 / THF solutions tested at excitation wavelengths of 356 nm and 401 nm, respectively, in which (a) is at an excitation wavelength of 356 nm and (b) is at an excitation wavelength of 401 nm;

[0034] Figure 7 Scatter plots of fluorescence intensity of EHBP1 / THF solutions and Fe 2+ concentrations and their linear fitting lines, in which (a) is at an excitation wavelength of 356 nm and (b) is at an excitation wavelength of 356 nm for Fe 2+ concentrations;

[0035] Figure 8 Scatter plots of fluorescence intensity of EHBP1 / THF solutions and Fe 3+ concentrations and their linear fitting lines, in which (a) is at an excitation wavelength of 356 nm and (b) is at an excitation wavelength of 356 nm for Fe 3+ concentrations;

[0036] Figure 9 Scatter plots of fluorescence intensity of EHBP1 / THF solutions and Fe 2+ concentrations and their linear fitting lines, in which (a) is at an excitation wavelength of 401 nm and (b) is at an excitation wavelength of 401 nm for Fe 2+ concentrations;

[0037] Figure 10 Scatter plots of fluorescence intensity of EHBP1 / THF solutions and Fe 3+ concentrations and their linear fitting lines, in which (a) is at an excitation wavelength of 401 nm and (b) is at an excitation wavelength of 401 nm for Fe 3+ concentrations;

[0038] Figure 11 Electrochemical Bode plots of the anticorrosive coatings for Examples 17-19 and Comparative Example 23 after immersion in 3.5 wt% NaCl solution for 60 days;

[0039] Figure 12 Physical and fluorescent images of the coating for Example 24 after immersion in 10 wt% H2SO4 solution for 0 h, 800 h and 1586 h, respectively;

[0040] Figure 13 Physical and fluorescent images of the coating for Comparative Example 26. DETAILED DESCRIPTION

[0041] The present application provides a preparation method of polycyclic aryl hyperbranched epoxy resin, comprising the following steps:

[0042] The multifunctional epoxy compound and the polycyclic aryl diphenol are subjected to a branched polymerization reaction under the condition of a catalyst to obtain the polycyclic aryl hyperbranched epoxy resin.

[0043] The mass ratio of the multifunctional epoxy compound, the polycyclic aryl diphenol and the catalyst is 100:20-60:0.01-0.02.

[0044] The multifunctional epoxy compound in the present application preferably comprises one or more of trimethylolpropane triglycidyl ether, glycerol triglycidyl ether, 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester, triphenylolmethane triglycidyl ether and pentaerythritol tetraglycidyl ether; when the multifunctional epoxy compound comprises several components simultaneously, the components are preferably combined in equal mass ratio.

[0045] The polycyclic aryl diphenol in the present application preferably comprises one or more of bisphenol fluorene, 9,9-bis(6-hydroxy-2-naphthol) fluorene, 4,4'-dihydroxydiphenyl, 2,2'-dihydroxydiphenyl, 3,3',5,5'-tetramethyl-4,4'-dihydroxydiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenyl sulfide, 1,1'-binaphthol, 2,2-bis-(4-hydroxyphenyl) hexafluoropropane, 4,4'-dihydroxydiphenyl sulfone, bis(4-hydroxyphenyl) phenylphosphine oxide, 4,4'-(1-phenylethyl) bisphenol, 4,4'-dihydroxybenzophenone, 4,4'-benzylidene bisphenol and 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide; when the polycyclic aryl diphenol comprises several components simultaneously, the components are preferably combined in equal mass ratio.

[0046] The catalyst preferably comprises one or more of tetrabutylammonium iodide, tetrabutylammonium chloride, tetrabutylammonium bromide, triphenylphosphonium bromide and ethyl triphenylphosphonium chloride; when the catalyst comprises several components, the components are preferably mixed in equal mass ratio.

[0047] The branched polymerization reaction preferably has a temperature of 100-180℃, further preferably 120-160℃, and more preferably 130-150℃. The branched polymerization reaction preferably has a time of 2-10h, further preferably 3-8h, and more preferably 5-6h. The branched polymerization reaction is preferably carried out under stirring in an inert atmosphere, preferably nitrogen atmosphere.

[0048] The preparation method preferably comprises the following steps: heating the multifunctional epoxy compound and the polycyclic aryl diphenol to the branched polymerization reaction temperature under stirring, and then adding the catalyst to carry out the branched polymerization reaction. After the branched polymerization reaction is completed, the product is preferably cooled to obtain the polycyclic aryl hyperbranched epoxy resin.

[0049] The application further provides a polycyclic aryl hyperbranched epoxy resin prepared by the preparation method.

[0050] The polycyclic aryl hyperbranched epoxy resin comprises one or more components of the multifunctional epoxy compound and one or more components of the polycyclic aryl diphenol, which are simultaneously subjected to the branched polymerization reaction. In the same branched product, one or more components of the multifunctional epoxy compound and one or more components of the polycyclic aryl diphenol are contained.

[0051] The polycyclic aryl hyperbranched epoxy resin of the application has the following structural formula:

[0052]

[0053] wherein, is one or more of

[0054] is one or more of

[0055] In the above structural formula, may be the same or different; may be the same or different; wherein, in indicates that the in indicates that the The above structural formula is not the structural formula of the final product.

[0056] The present application also provides a photoluminescent solution comprising the polycyclic aryl hyperbranched epoxy resin, the photoluminescent solution comprising the polycyclic aryl hyperbranched epoxy resin and an organic solvent.

[0057] The mass ratio of the polycyclic aryl hyperbranched epoxy resin and the organic solvent is 0.1-1:50-250.

[0058] The mass ratio of the polycyclic aryl hyperbranched epoxy resin and the organic solvent is preferably 0.3-0.8:100-200, further preferably 0.4-0.7:120-160, and more preferably 0.5-0.6:140-150.

[0059] The organic solvent is preferably a conventional organic solvent, and is further preferably one or more of N,N'-dimethylformamide, N,N'-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone and tetrahydrofuran; when the organic solvent comprises several components, the components are preferably mixed in equal mass ratio.

[0060] The polycyclic aryl hyperbranched epoxy resin and the organic solvent are preferably mixed uniformly to obtain the photoluminescent solution, and the mixing is preferably carried out under stirring, and is further preferably carried out under stirring and heating.

[0061] The present application also provides an application of the photoluminescent solution in metal ion detection.

[0062] The metal ion is preferably Zn 2+ , Na + , Li + , Ba 2+ , Ca 2+ , Mg 2+ , Al 3+ , Ni 2+ , Cd 2+ , Co 2+ , Cu 2 + , Fe 2+ or Fe 3+ .

[0063] The present application also provides a hyperbranched epoxy anticorrosive coating comprising the polycyclic aryl hyperbranched epoxy resin, comprising component A and component B.

[0064] The component A comprises the following components in the following mass parts: polycyclic aryl hyperbranched epoxy resin 5-50 parts, bisphenol A type epoxy resin 50-95 parts, auxiliary agent 0.5-5 parts, and organic solvent 20-55 parts.

[0065] The B component is an organic amine curing agent;

[0066] The ratio of the epoxy equivalent weight in the A component and the active hydrogen equivalent weight in the B component is 1:0.8-1.2.

[0067] The A component of the present application comprises 5-50 parts of polycyclic aryl hyperbranched epoxy resin, preferably 10-40 parts, further preferably 20-30 parts, and more preferably 23-26 parts.

[0068] The A component of the present application comprises 50-95 parts of bisphenol A type epoxy resin, preferably 60-90 parts, further preferably 70-80 parts, and more preferably 73-76 parts.

[0069] The A component of the present application comprises 0.5-5 parts of auxiliary agent, preferably 1-4 parts, and further preferably 2-3 parts; the auxiliary agent comprises a defoaming agent and a leveling agent; the mass ratio of the defoaming agent and the leveling agent is preferably 1-2:1-2, and further preferably 1:1.

[0070] The A component of the present application comprises 20-55 parts of organic solvent, preferably 25-50 parts, further preferably 30-40 parts, and more preferably 33-37 parts; the organic solvent is preferably a conventional organic solvent, and further preferably one or more of N,N'-dimethylformamide, N,N'-dimethylacetamide, dimethyl sulfoxide, N-methyl pyrrolidone, dimethylbenzene, butanone, and tetrahydrofuran; when the organic solvent comprises several components, the components are preferably mixed in equal mass ratio.

[0071] The ratio of the epoxy equivalent weight in the A component and the active hydrogen equivalent weight in the B component of the present application is preferably 1:0.9-1.1, and further preferably 1:1.

[0072] The present application also provides a use of the hyperbranched epoxy anticorrosive coating in predicting the failure of steel anticorrosive coating.

[0073] The technical solutions provided by the present application will be described in detail below in conjunction with the examples, but they should not be understood as limiting the scope of protection of the present application.

[0074] Example 1

[0075] 286.32g of 1,1'-binaphthyl and 604.72g of trimethylolpropane triglycidyl ether were heated to 100°C under stirring, and a catalyst was added under nitrogen atmosphere for 8h, wherein the catalyst was 0.08g of tetrabutylammonium iodide and 0.04g of ethyl triphenylphosphonium chloride, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP1.

[0076] Example 2

[0077] The 286.32 g of 1,1'-binaphthyl-2-ol in Example 1 was replaced with 186.21 g of 4,4'-dihydroxydiphenyl, and other conditions were the same as in Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP4.

[0078] Example 3

[0079] The 286.32 g of 1,1'-binaphthyl-2-ol in Example 1 was replaced with 186.21 g of 4,4'-dihydroxydiphenyl, and other conditions were the same as in Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP4.

[0080] The nuclear magnetic resonance hydrogen spectrum of EHBP1, EHBP2 and EHBP3 in Examples 1-3 is shown in Figures 1-3 The infrared spectrum of EHBP1, EHBP2 and EHBP3 in Examples 1-3 is shown in Figure 4

[0081] Example 4

[0082] The 286.32 g of 1,1'-binaphthyl-2-ol in Example 1 was replaced with 186.21 g of 4,4'-dihydroxydiphenyl, and other conditions were the same as in Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP4.

[0083] Example 5

[0084] The 286.32 g of 1,1'-binaphthyl-2-ol in Example 1 was replaced with 186.21 g of 4,4'-dihydroxydiphenyl, and other conditions were the same as in Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP4.

[0085] Example 6

[0086] The 286.32 g of 1,1'-binaphthyl-2-ol in Example 1 was replaced with 186.21 g of 4,4'-dihydroxydiphenyl, and other conditions were the same as in Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP4.

[0087] Example 7

[0088] The 286.32 g of 1,1'-binaphthyl-2-ol in Example 1 was replaced with 186.21 g of 4,4'-dihydroxydiphenyl, and other conditions were the same as in Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP4.

[0089] Example 8

[0090] ​The 1,1'-binaphthyl-2-ol in Example 1 is replaced with an equal molar amount of 4,4'-dihydroxydiphenyl sulfide, the trimethylolpropane triglycidyl ether is replaced with an equal molar amount of glycerol triglycidyl ether, and the other conditions are the same as in Example 1, and the obtained polycyclic aryl hyperbranched epoxy resin is recorded as EHBP8.

[0091] Example 9

[0092] The 1,1'-binaphthyl-2-ol in Example 1 is replaced with an equal molar amount of 2,2-bis-(4-hydroxyphenyl)hexafluoropropane, the trimethylolpropane triglycidyl ether is replaced with an equal molar amount of 4,5-epoxycyclohexane-1,2-dicarboxylic acid diglycidyl ester, and the other conditions are the same as in Example 1, and the obtained polycyclic aryl hyperbranched epoxy resin is recorded as EHBP9.

[0093] Example 10

[0094] The 1,1'-binaphthyl-2-ol in Example 1 is replaced with an equal molar amount of 4,4'-dihydroxydiphenyl sulfone, the trimethylolpropane triglycidyl ether is replaced with an equal molar amount of triphenol methane triglycidyl ether, and the other conditions are the same as in Example 1, and the obtained polycyclic aryl hyperbranched epoxy resin is recorded as EHBP10.

[0095] Example 11

[0096] The 1,1'-binaphthyl-2-ol in Example 1 is replaced with an equal molar amount of bis(4-hydroxyphenyl)phenyl phosphine oxide, the trimethylolpropane triglycidyl ether is replaced with an equal molar amount of pentaerythritol tetraglycidyl ether, and the other conditions are the same as in Example 1, and the obtained polycyclic aryl hyperbranched epoxy resin is recorded as EHBP11.

[0097] Example 12

[0098] The 1,1'-binaphthyl-2-ol in Example 1 is replaced with an equal molar amount of 4,4'-(1-phenylethyl) bisphenol, the catalyst is replaced with 0.06 g of tetrabutylammonium chloride, and the other conditions are the same as in Example 1, and the obtained polycyclic aryl hyperbranched epoxy resin is recorded as EHBP12.

[0099] Example 13

[0100] The 1,1'-binaphthyl-2-ol in Example 1 is replaced with an equal molar amount of 4,4'-dihydroxybenzophenone, the catalyst is replaced with 0.08 g of tetrabutylammonium bromide, the reaction temperature is 120°C, and the other conditions are the same as in Example 1, and the obtained polycyclic aryl hyperbranched epoxy resin is recorded as EHBP13.

[0101] Example 14

[0102] The 1,1'-binaphthyl-2-ol in Example 1 was replaced with equimolar amount of 4,4'-diphenylmethane bisphenol, the reaction temperature was 160℃, the time was 3h, and other conditions were the same as Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP14.

[0103] Example 15

[0104] The 1,1'-binaphthyl-2-ol in Example 1 was replaced with equimolar amount of 10-(2,5-dihydroxyphenyl)-10H-9-oxa-10-phosphaphenanthrene-10-oxide, the reaction temperature was 140℃, the time was 5h, and other conditions were the same as Example 1, to obtain a polycyclic aryl hyperbranched epoxy resin, which was recorded as EHBP15.

[0105] Example 16

[0106] Different amounts of EHBP1 were added into 100 mL of tetrahydrofuran (THF) to prepare solutions with concentrations of 200 mg / mL, 100 mg / mL, 50 mg / mL, 40 mg / mL, 30 mg / mL, 20 mg / mL, 15 mg / mL, 10 mg / mL, and 7.5 mg / mL, respectively. The fluorescence spectra of the solutions were tested under excitation wavelengths of 356 nm and 401 nm, respectively, as shown in Figure 5 , where (a) is the excitation wavelength of 356 nm, and (b) is the excitation wavelength of 401 nm.

[0107] 375 mg of EHBP1 and 100 mL of tetrahydrofuran were mixed and stirred thoroughly to obtain a uniform solution. Zinc chloride, sodium chloride, lithium chloride, barium chloride, calcium chloride, magnesium chloride, aluminum chloride, nickel chloride, cadmium chloride, cobalt chloride, copper chloride, ferrous chloride, and ferric chloride were added to the uniform solution. The fluorescence spectra of the EHBP1 / THF solution were tested under excitation wavelengths of 356 nm and 401 nm, respectively, and the results are shown in Figure 6 , where (a) is the excitation wavelength of 356 nm, and (b) is the excitation wavelength of 401 nm.

[0108] 375 mg of EHBP1 and 100 mL of tetrahydrofuran were mixed and stirred thoroughly to obtain a uniform solution. Ferrous chloride and ferric chloride were added to the uniform solution, respectively.

[0109] The fluorescence intensity of the EHBP1 / THF solution and the Fe 2+ / Fe 3+ concentration were tested under an excitation wavelength of 356 nm, and the scatter plot and linear fitting line thereof are shown in Figure 7 , 8 . Figure 7(a) is the excitation wavelength of 356 nm, (b) is the excitation wavelength of 356 nm Fe 2+ The scatter plot of the concentration and its linear fitting line. Figure 8 (a) is the excitation wavelength of 356 nm, (b) is the excitation wavelength of 356 nm Fe 3+ The scatter plot of the concentration and its linear fitting line.

[0110] The fluorescence intensity of the EHBP1 / THF solution was tested under the excitation wavelength of 401 nm, and the detection limit of Fe 2+ / Fe 3+ The scatter plot of the concentration and its linear fitting line, as shown in Figure 9 、 10 . Figure 9 (a) is the excitation wavelength of 401 nm, (b) is the excitation wavelength of 401 nm Fe 2+ The scatter plot of the concentration and its linear fitting line. Figure 10 (a) is the excitation wavelength of 401 nm, (b) is the excitation wavelength of 401 nm Fe 3+ The scatter plot of the concentration and its linear fitting line.

[0111] The detection limit of Fe 2+ and Fe 3+ by the EHBP1 / THF solution under different excitation wavelengths is shown in Table 1.

[0112] Table 1 Detection limit of Fe 2+ and Fe 3+ by the EHBP1 / THF solution

[0113]

[0114] Example 17

[0115] 5g of EHBP1, 69g of bisphenol A type epoxy resin E51, 25g of solvent (volume ratio of xylene and butanone is 6:4), 0.5g of leveling agent BYK-306 and 0.5g of defoaming agent BYK-141 were mixed, and phenolic amine curing agent PLR730 was added according to the epoxy equivalent: active hydrogen equivalent = 1:1, stirred and mixed uniformly, and then sprayed on a carbon steel plate after standing for 20 minutes. After curing at room temperature for 24h, it was placed in a 60℃ oven for 6h to obtain a hyperbranched epoxy anticorrosive coating.

[0116] Example 18

[0117] The mass of EHBP1 in Example 17 was changed to 7g, and the other conditions were the same as in Example 17.

[0118] Example 19

[0119] The mass of EHBP1 in Example 17 is changed to 9g, and other conditions are the same as those in Example 17.

[0120] Example 20

[0121] 5g EHBP1 in Example 17 is replaced by 5g EHBP2, and other conditions are the same as those in Example 17.

[0122] Example 21

[0123] 5g EHBP1 in Example 17 is replaced by 7g EHBP2, and other conditions are the same as those in Example 17.

[0124] Example 22

[0125] 5g EHBP1 in Example 17 is replaced by 9g EHBP2, and other conditions are the same as those in Example 17.

[0126] Comparative Example 23

[0127] 5g EHBP1 in Example 17 is replaced by 5g E51, and other conditions are the same as those in Example 17.

[0128] Example 24

[0129] 50g EHBP1, 50g solvent (volume ratio of xylene and butanone is 6:4), 0.5g leveling agent BYK-306 and 0.5g defoaming agent BYK-141 are mixed, and diethylenetriamine is added according to the ratio of epoxy equivalent: active hydrogen equivalent = 1:1, stirred and mixed uniformly, and then sprayed on a carbon steel plate after standing for 20 minutes, to obtain a primer layer. The primer layer is dried, and then a corrosion-resistant layer is sprayed. The preparation method of the corrosion-resistant layer is as follows: 7g EHBP1 resin, 63g bisphenol A type epoxy resin E51, 25g solvent (volume ratio of xylene and butanone is 6:4), 0.5g leveling agent BYK-306 and 0.5g defoaming agent BYK-141 are mixed, and phenolic amine curing agent PLR730 is added according to the ratio of epoxy group: active hydrogen = 1:1, stirred and mixed uniformly, and then sprayed on a carbon steel plate after standing for 20 minutes, to obtain a primer layer. The dry film thickness is 85um. After being cured at room temperature for 24h, it is placed in a 60℃ oven for 6h, to obtain a primer corrosion-resistant coating.

[0130] Example 25

[0131] EHBP1 in Example 24 is replaced by an equal mass of EHBP4, and other conditions are the same as those in Example 24.

[0132] Comparative Example 26

[0133] EHBP1 in Example 24 is replaced by an equal mass of E51, and other conditions are the same as those in Example 24.

[0134] The double-sided sprayed carbon steel plates of Examples 17-22 and Comparative Example 23 were placed in 3.5wt% NaCl solution, 10wt% H2SO4 solution, 5wt% NaOH solution and deionized water, and the time for the coating to bubble, rust and fall off was observed to test the medium resistance of the coating, and the results are shown in Table 2.

[0135] Table 2 Test results of medium resistance of the coating of Examples 17-22 and Comparative Example 23

[0136]

[0137]

[0138] Note: + indicates that the time is still increasing.

[0139] The electrochemical performance of the coating was tested using a ZAHNER type electrochemical workstation, the test was carried out at 23°C, the test voltage was 20mV, the test frequency range was 10 -2 ~ 10 5 Hz, the test electrolyte was 3.5wt% NaCl solution, and the contact area of the coating with the test electrolyte solution was 10cm 2 .

[0140] The electrochemical Bode spectrum of the anticorrosive coating of Examples 17-19 and Comparative Example 23 after immersion in 3.5wt% NaCl solution for 60 days is shown in Figure 11 .

[0141] As can be seen from Table 2 and Figure 11 , the polycyclic aromatic hyperbranched epoxy resin can greatly increase the medium resistance of bisphenol A type epoxy resin E51, and there is an optimal addition ratio of the polycyclic aromatic hyperbranched epoxy resin, which can significantly improve the medium resistance of the anticorrosive coating when the addition amount is 5-7% of the total mass of the coating.

[0142] The double-sided sprayed carbon steel plates of Examples 24, 25 and Comparative Example 26 were immersed in 10wt% H2SO4 solution, and the carbon steel plates were taken out at regular intervals, the solution on the surface of the carbon steel plates was wiped off, and whether bubbles, rust and other phenomena appeared on the surface of the carbon steel plates was observed, then the carbon steel plates were placed under a fluorescence microscope to observe the fluorescence brightness of the carbon steel plates and take photos to record, and the anticorrosion performance of the coating was predicted. The test results of the predicted performance of the anticorrosive coating of Examples 24, 25 and the coating of Comparative Example 26 are shown in Table 3.

[0143] Table 3 Test results of the predicted performance of the coating

[0144]

[0145] The photographs and fluorescence images of the precoat of Example 24 immersed in 10 wt% sulfuric acid solution for 0 h, 800 h and 1586 h, respectively, are shown in Figure 12 The photographs and fluorescence images of the coating of Comparative Example 26 are shown in Figure 13

[0146] From Table 3 and Figure 12 , 13 it can be seen that the fluorescence intensity of the precoat decreases with the extension of the immersion time of the coating, and when blistering occurs on the carbon steel plate, it means that the barrier property of the coating has been damaged, and the fluorescence intensity of the coating of Example 24 also decreases from the initial 35 to 0.7, achieving the precoat failure. The coating of Comparative Example 26 of pure E51 resin has substantially no fluorescence brightness at the beginning, and the barrier property is obviously worse than that of the coating with EHBP.

[0147] The above only describes the preferred embodiments of the present application, and it should be noted that for those skilled in the art, some improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as the protection scope of the present application.​

Claims

1. The application of a hyperbranched epoxy anti-corrosion coating in predicting the failure of steel anti-corrosion coatings, wherein the hyperbranched epoxy anti-corrosion coating comprises component A and component B; Component A comprises the following components in parts by weight: 5-50 parts of polycyclic aryl hyperbranched epoxy resin, 50-95 parts of bisphenol A type epoxy resin, 0.5-5 parts of additives, and 20-55 parts of organic solvent. Component B is an organic amine curing agent; The ratio of epoxy equivalent in component A to active hydrogen equivalent in component B is 1:0.8 to 1.

2. The polycyclic aryl hyperbranched epoxy resin is obtained by the following preparation method; The preparation method includes the following steps: A branching polymerization reaction was carried out on a multifunctional epoxy compound and a polycyclic aryl diphenol under catalytic conditions to obtain a polycyclic aryl hyperbranched epoxy resin. The mass ratio of the polyfunctional epoxy compound, the polycyclic aryl diphenol, and the catalyst is 100:20-60:0.01-0.02; The polycyclic aromatic diphenol comprises one or more of 4,4'-dihydroxybiphenyl, 2,2'-dihydroxybiphenyl, 3,3',5,5'-tetramethyl-4,4'-dihydroxybiphenyl and 1,1'-bi-2-naphthol; The catalyst comprises one or more of tetrabutylammonium iodide, triphenylphosphine bromide and ethyltriphenylphosphine chloride; The multifunctional epoxy compound is trimethylolpropane triglycidyl ether.

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