Waterborne epoxy micaceous iron coating as well as preparation method and application thereof

Abstract

The invention discloses a waterborne epoxy micaceous iron coating and a preparation method and application thereof, and relates to the technical field of anticorrosive paints.The waterborne epoxy micaceous iron coating comprises a component A and a component B. The component A and the component B are prepared from raw materials including the following components: the component A comprises waterborne epoxy emulsion, micaceous iron ash, an anti-settling agent, pigment filler and an auxiliary A; the component B comprises a waterborne epoxy curing agent; the component A is prepared from the following components in parts by weight: 100 parts of waterborne epoxy emulsion; 20-170 parts by weight of micaceous iron ash; 0.5-6 parts by weight of an anti-settling agent; 20-80 parts by weight of pigment and filler; 1-8 parts by weight of an auxiliary agent A; the component B comprises the following components in parts by weight: 100 parts of a waterborne epoxy curing agent; the weight ratio of the component A to the component B is (8-12): 1. The waterborne epoxy micaceous iron coating disclosed by the invention has the advantages of low VOC (Volatile Organic Compounds), relatively good sealing property, sagging prevention, sedimentation prevention, high adhesive force and the like.

Description

Technical Field

[0001] The invention relates to the technical field of anti-corrosion coatings, and more particularly to a water-based epoxy micaceous iron coating and a preparation method and application thereof. Background Art

[0002] With the increasing requirements for environmental protection at home and abroad, and my country's requirements for low VOC emissions of coating products, water-based coating products are gradually replacing existing solvent-based coating systems and are widely used in industries such as industry, construction, petrochemicals, and ships. In the field of anti-corrosion coatings, epoxy micaceous iron intermediate paint is usually used in conjunction with anti-corrosion primers to improve the sealing of the coating system and improve the anti-corrosion performance. The service life of the supporting system can reach 15 to 20 years.

[0003] Compared with the excellent physical and chemical properties of solvent-based epoxy micaceous iron coatings, water-based epoxy micaceous iron coatings still have gaps in anti-sagging and anti-settling properties compared with solvent-based products, and cannot meet the construction requirements of single-layer thickness. At the same time, there is also a certain gap in the sealing of the coating. The existence of the above problems has restricted the promotion and use of water-based epoxy micaceous iron coatings. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a water-based epoxy micaceous iron coating and a preparation method and application thereof. The water-based epoxy micaceous iron coating of the present invention has the advantages of low VOC, good sealing, anti-sagging, anti-settling, and high adhesion. The water-based epoxy micaceous iron coating has a long application period, and the construction can be selected by roller coating, brush coating, air spraying, airless spraying and the like, and the single-layer film thickness can reach more than 400μm. It can be matched with various types of primers, has a wide range of applications, and the effective life of the paint film is up to 15 to 20 years.

[0005] One of the purposes of the present invention is to provide a waterborne epoxy micaceous iron coating, wherein the waterborne epoxy micaceous iron coating comprises a component A and a component B, wherein the component A and the component B are prepared from raw materials comprising the following components respectively:

[0006] Component A includes water-based epoxy emulsion, micaceous iron ash, anti-settling agent, pigments and fillers, and additive A;

[0007] Component B is a water-based epoxy curing agent;

[0008] The A component is calculated by weight:

[0009] 100 parts by weight of water-based epoxy emulsion;

[0010] 20-170 parts by weight of micaceous iron ash;

[0011]

[0012] The weight ratio of component A to component B is (8-12):1.

[0013] Preferably, the A component comprises the following components by weight:

[0014] 100 parts by weight of water-based epoxy emulsion;

[0015] 36-72 parts by weight of micaceous iron ash;

[0016]

[0017] The weight ratio of component A to component B is (9.5-11.5):1.

[0018] Preferably, the aqueous epoxy emulsion is at least one of bisphenol A epoxy emulsion, bisphenol F epoxy emulsion, acrylic epoxy emulsion, modified epoxy emulsion A, and modified epoxy emulsion B; and / or,

[0019] The micaceous iron ash, i.e., mica iron oxide ash, has a mesh size of 400-800 meshes; and / or,

[0020] The anti-settling agent is at least one of organic bentonite, attapulgite, lithium magnesium silicate, wax powder, wax powder dispersion, and fumed silica, which can increase the sedimentation level of the coating, improve the anti-sagging property of the coating, and thus increase the thickness of a single paint film, reduce the number of constructions, and shorten the construction period; and / or,

[0021] The pigment filler is at least one of phosphate anti-rust pigments, kaolin, talc, mica powder, wollastonite powder, precipitated barium sulfate, titanium dioxide, silicon powder, composite iron titanium powder, heavy calcium carbonate, light calcium carbonate, activated calcium carbonate, calcite powder, dolomite powder, quartz powder, and feldspar powder, which can improve the corrosion resistance and hardness of the paint film, increase the sealing property of the paint film, reduce the roughness, improve the hiding property of the paint film, prevent the slurry from settling, and adjust the slurry viscosity; and / or,

[0022] The auxiliary agent A is at least one of a dispersant, a thickener, a wetting agent, a defoamer, a leveling agent, a pH adjuster, an adhesion promoter, an anti-flash rust agent, and a corrosion inhibitor, and the technicians can add it according to the actual situation; and / or,

[0023] The water-based epoxy curing agent is an amine curing agent; preferably, the amine curing agent is at least one of a fatty amine curing agent, alicyclic amine curing agent, phenolic amine curing agent, polyamide curing agent, and modified epoxy curing agent, preferably a multi-functional curing agent with a network structure, which can increase the sealing of the paint film and improve the corrosion resistance. Preferably, two or more curing agents with different curing rates are mixed to take into account the requirements of workability and application period.

[0024] Preferably, the molecular structure formula of the modified epoxy emulsion A is:

[0025]

[0026] Wherein n is any integer between 100 and 150;

[0027] Preferably,

[0028] The modified epoxy emulsion A is prepared by emulsion polymerization of raw materials including the following components:

[0029] 4-Hydroxybutyl acrylate glycidyl ether, di(ethylene glycol)ethyl ether methacrylate, catalyst, emulsifier and deionized water;

[0030] Further preferably, the molar ratio of 4-hydroxybutyl acrylate glycidyl ether to di(ethylene glycol)ethyl ether methacrylate is 1:(0.8-1.2), preferably 1:(0.9-1.05); and / or,

[0031] The molar ratio of the catalyst to the total amount of 4-hydroxybutyl acrylate glycidyl ether and di(ethylene glycol)ethyl ether methacrylate is (0.1-0.7):100; and / or,

[0032] The molar ratio of the emulsifier to the total amount of 4-hydroxybutyl acrylate glycidyl ether and di(ethylene glycol)ethyl ether methacrylate is (0.5-10):100; and / or,

[0033] More preferably, the catalyst is at least one of ammonium persulfate, potassium persulfate, azobisisobutylnitrile, azobisisoheptylnitrile, azobisisobutylamidine hydrochloride, and azobisisobutylimidazoline hydrochloride; and / or,

[0034] The emulsifier is an anionic emulsifier or a nonionic emulsifier;

[0035] The anionic emulsifier is an alkyl salt, preferably at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, potassium dodecyl sulfate, dodecyltrimethylammonium bromide, alkyl vinyl sulfonate, and sodium allyl ether hydroxypropyl sulfonate;

[0036] The nonionic emulsifier is at least one of aliphatic glyceride, polyol emulsifier, polyoxyethylene fatty alcohol ether, and polyoxyethylene polyoxypropylene copolymer.

[0037] Preferably, the modified epoxy emulsion A is prepared by the following method:

[0038] (1) mixing part of 4-hydroxybutyl acrylate glycidyl ether monomer and part of diethylene glycol ethyl ether methacrylate monomer, and dispersing the mixture with part of emulsifier in deionized water to obtain a pre-emulsion;

[0039] The part of 4-hydroxybutyl acrylate glycidyl ether monomer accounts for 10-40% of the total mass of 4-hydroxybutyl acrylate glycidyl ether monomer;

[0040] The part of di(ethylene glycol) ethyl ether methacrylate monomer accounts for 10-40% of the total mass of di(ethylene glycol) ethyl ether methacrylate monomer;

[0041] The partial emulsifier accounts for 5-40% of the total mass of the emulsifier;

[0042] The mass concentration of the total mass of the part of 4-hydroxybutyl acrylate glycidyl ether monomer and the part of di(ethylene glycol) ethyl ether methacrylate monomer in deionized water is 20-40wt%;

[0043] (2) dispersing the catalyst in deionized water to obtain a catalyst dispersion;

[0044] The mass concentration of the catalyst after being dissolved in deionized water is 15 to 50 wt %;

[0045] (3) under a protective gas atmosphere at 60-80° C., adding a portion of the catalyst dispersion to the pre-emulsified liquid to react to obtain a seed solution;

[0046] The part of the catalyst dispersion accounts for 5-40% of the total mass of the catalyst dispersion;

[0047] (4) under a protective gas atmosphere, adding the remaining catalyst dispersion, the remaining 4-hydroxybutyl acrylate glycidyl ether, the remaining diethylene glycol ether methacrylate, and the remaining emulsifier to the seed solution, performing a polymerization reaction, and adding a pH adjuster to obtain the modified epoxy emulsion A;

[0048] The polymerization reaction temperature is 70-90° C., the reaction time is 0.5-4 hours, and the pH adjustment range is 7-11.

[0049] The reaction equation of the modified epoxy emulsion A is as follows:

[0050]

[0051] The specific scheme is as follows:

[0052] (1-1) 4-hydroxybutyl acrylate glycidyl ether and diethylene glycol ethyl ether methacrylate are passed through an alumina column to remove the polymerization inhibitor;

[0053] (1-2) dispersing a mixture of 10 to 40% by weight of 4-hydroxybutyl acrylate glycidyl ether and 10 to 40% by weight of diethylene glycol ethyl ether methacrylate and 5 to 40% by weight of an emulsifier in deionized water at a high speed of 600 to 2000 rpm under N2 protection and a constant temperature of 30 to 40°C for about 15 to 30 minutes to obtain a pre-emulsion;

[0054] (2-1) preparing a catalyst aqueous dispersion under high-speed dispersion to a catalyst concentration of 15 to 50%;

[0055] (2-2) preparing a mixed solution of the remaining 4-hydroxybutyl acrylate glycidyl ether, di(ethylene glycol) ethyl ether methacrylate and the remaining emulsifier under high-speed dispersion;

[0056] (2-3) under N2 protection, 10-40% of the aqueous dispersion of the catalyst in step (2-1) was added dropwise to the pre-emulsion at a constant temperature of 60-80° C., and the reaction was continued for 30-60 minutes to obtain a seed solution;

[0057] (3-1) Under N2 protection, under high-speed dispersion, the remaining catalyst aqueous dispersion and the mixture in step (2-2) are respectively added dropwise to the seed solution, and the reaction system temperature is maintained at 70-90°C. After the addition is completed, the polymerization reaction is continued for 0.5-4h and then stopped;

[0058] (3-2) adding a pH adjuster to adjust the pH value of the system to 7-11, and filtering to obtain the modified epoxy emulsion A.

[0059] Preferably, the molecular structure formula of the modified epoxy emulsion B is:

[0060]

[0061] Preferably,

[0062] The modified epoxy emulsion B is prepared from raw materials including the following components:

[0063] Isophorone diisocyanate, tripropylene glycol methyl ether, and 3-(oxiranylmethoxy)-2,2-bis[(oxiranylmethoxy)methyl]propanol;

[0064] The molar ratio of isophorone diisocyanate, tripropylene glycol methyl ether and 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol is 1:(0.7-1):(0.7-1); preferably 1:(0.8-0.95):(0.8-0.95).

[0065] Preferably, the modified epoxy emulsion B is prepared by the following method:

[0066] (1) in a protective gas atmosphere, isophorone diisocyanate is dispersed at high speed and heated, dehydrated tripropylene glycol methyl ether is added dropwise, and the temperature is raised to react;

[0067] The isophorone diisocyanate is heated to 50-60°C, the temperature of the temperature rise reaction is 80-90°C, and the reaction time is 1-2h;

[0068] (2) after cooling, add dehydrated 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol dropwise, and continue to heat the reaction;

[0069] The cooling temperature is 50-60°C, the heating reaction temperature is 80-90°C, and the reaction time is 1-2h;

[0070] (3) slowly adding deionized water into the reaction system to adjust the solid content to obtain the modified epoxy emulsion B;

[0071] The solid content is 40-50%.

[0072] The modified epoxy emulsion B is a nonionic epoxy emulsion prepared from isophorone diisocyanate, tripropylene glycol methyl ether and 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol, and the specific reaction equation is as follows:

[0073]

[0074] The specific scheme is as follows:

[0075] (1) In a vacuum state, heat tripropylene glycol methyl ether to 105-115° C. under high-speed dispersion, dehydrate for 1-2 hours, and cool to room temperature;

[0076] (2) heating 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol to 105-115° C. under vacuum and high-speed dispersion, dehydrating for 2 h, and cooling to room temperature;

[0077] (3) Under N2 protection and high-speed dispersion, isophorone diisocyanate is heated to 50-60° C., and tripropylene glycol methyl ether in step (1) is added dropwise within 0.5-1 h. The temperature is maintained at 80-90° C. for 1-2 h, and the NCO content is measured until it is close to the theoretical value;

[0078] (4) Under N2 protection and high-speed dispersion, the reaction system is cooled to 50-60°C, and the 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol in step (2) is slowly added dropwise within 0.5-1 hour. The temperature is maintained at 80-90°C for 1-2 hours, and the NCO content is measured until the reaction is complete, and the temperature is cooled to room temperature;

[0079] (5) Slowly add deionized water to the reaction system under high-speed dispersion to adjust the solid content to 40-50%, and obtain the modified epoxy emulsion B.

[0080] Preferably, the molecular structural formula of the modified epoxy curing agent is:

[0081]

[0082] Wherein n is any integer from 1 to 10;

[0083] Preferably,

[0084] The modified epoxy curing agent is prepared from raw materials including the following components:

[0085] Bisphenol A diglycidyl ether, tris(2-aminoethyl)amine, and ethylene glycol diglycidyl ether;

[0086] The molar ratio of bisphenol A diglycidyl ether: tris(2-aminoethyl)amine: ethylene glycol diglycidyl ether is (0.8-1.2):1:(0.8-1.2); preferably (0.9-1.1):1:(0.9-1.1);

[0087] Preferably,

[0088] The modified epoxy curing agent is prepared by the following method:

[0089] Under a protective gas atmosphere, bisphenol A diglycidyl ether is dispersed and dissolved in an organic solvent at a high speed, tri(2-aminoethyl)amine is added dropwise, the temperature is raised to react, ethylene glycol diglycidyl is added dropwise to continue the reaction, the temperature is lowered to room temperature, and a cosolvent is added to obtain the modified epoxy curing agent;

[0090] More preferably, the constant temperature is 30-40° C., the concentration of bisphenol A diglycidyl ether dissolved in the organic solvent is 40-60%, the temperature of the temperature rise reaction is 50-70° C., the reaction time is 1-2 hours, ethylene glycol diglycidol is added dropwise and the reaction is continued for 1-2 hours, and the solid content is 40-60%;

[0091] The co-solvent can be selected from commonly used co-solvents in the art, which are used to adjust the viscosity and drying rate of the system. Preferably, the co-solvent is non-toxic or low-toxic, and preferably at least one of alcohol ethers, alcohol esters, alcohols, acid esters, and ether esters; further preferably, the co-solvent is ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol butyl ether, ethylene glycol tert-butyl ether, ethylene glycol butyl ether acetate, ethylene glycol diacetate, diethylene glycol butyl ether, diethylene glycol tert-butyl ether, propylene glycol, propylene glycol methyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether, propylene glycol n-propyl ether, propylene glycol butyl ether, propylene glycol dioic acid acetate, propylene glycol phenyl ether, dipropylene glycol methyl ether, dipropylene glycol butyl ether, isopropyl alcohol, dibasic acid esters, alcohol esters dodecahydrate, and dioxydimethyl ether acetate.

[0092] The reaction equation of the modified epoxy curing agent is as follows:

[0093]

[0094] The specific preparation method is as follows:

[0095] (1) dissolving bisphenol A diglycidyl ether in an organic solvent at a concentration of 40 to 60% under N2 protection at a high speed of 600 to 1200 rpm and a constant temperature of 30 to 40°C to obtain a mixed solution;

[0096] (2) Add a solution of tri(2-aminoethyl)amine dropwise to the above mixed solution over 30 minutes, raise the temperature to 50-70°C, and react for 1-2 hours;

[0097] (3) adding a solution of ethylene glycol diglycidyl ether dropwise to the reaction solution of step (2) over 30 minutes and reacting for 1 to 2 hours;

[0098] (4) Cooling the reaction mixture to room temperature, adding a co-solvent to the reaction mixture, and adjusting the solid content to 40-60%, thereby obtaining the modified epoxy curing agent.

[0099] In the formulation of the present invention, conventional auxiliary agents, such as co-solvents, may be added to component A according to actual conditions. The amount of co-solvents is conventional and can be added by technicians according to actual conditions.

[0100] The second object of the present invention is to provide a method for preparing a water-based epoxy micaceous iron coating, the method comprising:

[0101] The components of component A are mixed according to the weight parts to obtain the component A; and the water-based epoxy micaceous iron coating is obtained by mixing component A and component B according to the dosage ratio.

[0102] The specific preparation method is as follows:

[0103] Component A: Use a high-speed disperser to disperse 40-60% of the aqueous epoxy emulsion, cosolvent, and additive component A at a stirring speed of 600-1000 r / min for about 10-30 minutes; then gradually add micaceous iron ash, anti-settling agent, pigments and fillers, and continue to disperse for 30-60 minutes; add the remaining aqueous epoxy emulsion, adjust the stirring speed to 800-2000 r / min, and disperse for 30-60 minutes; control the fineness to ≤30μm, filter, and package the material;

[0104] Component B: Disperse the mixture in the above amount using a high-speed disperser at a stirring speed of 600-2000 r / min for about 10-40 min, filter, and package the resulting mixture;

[0105] When in use, the component A and the component B are mixed in the proportion to obtain the waterborne epoxy micaceous iron coating.

[0106] The third object of the present invention is to provide a water-based epoxy micaceous iron coating for use in the field of corrosion protection.

[0107] The specific usage is as follows:

[0108] During construction, mix components A and B in proportion, dilute with deionized water or tap water, and use 5-20% of the total amount. It can be applied by roller coating, brush coating, air spraying, or airless spraying. The maximum single-layer film thickness can reach 400μm.

[0109] The waterborne epoxy micaceous iron coating of the present invention has the advantages of low VOC, good sealing, anti-sagging, anti-settling, high adhesion, etc. The waterborne epoxy micaceous iron coating has a long application period, and can be constructed by roller coating, brush coating, air spraying, airless spraying, etc., and the single-layer film thickness can reach more than 400 μm. It can be matched with various primers, has a wide range of applications, and the effective life of the paint film is as long as 15 to 20 years. DETAILED DESCRIPTION

[0110] The present invention is described in detail below in conjunction with the embodiments. It is necessary to point out that the following embodiments are only used to further illustrate the present invention and cannot be understood as limiting the scope of protection of the present invention. Some non-essential improvements and adjustments made to the present invention by those skilled in the art based on the contents of the present invention still fall within the scope of protection of the present invention.

[0111] Example 1

[0112] The raw materials and dosage of component A are as follows:

[0113]

[0114] The raw materials and dosage of component B are as follows:

[0115] Modified epoxy curing agent 100 parts by weight /

[0116] Preparation of modified epoxy emulsion A:

[0117] (1) 0.2 mol of 4-hydroxybutyl acrylate glycidyl ether monomer and 0.18 mol of diethylene glycol ethyl ether methacrylate monomer are mixed, and dispersed with 0.0114 mol of sodium dodecylbenzene sulfonate and 0.0076 mol of polyoxyethylene fatty alcohol ether in deionized water to obtain a pre-emulsion;

[0118] The total mass concentration of 4-hydroxybutyl acrylate glycidyl ether monomer and di(ethylene glycol) ethyl ether methacrylate monomer in deionized water is controlled to be 20wt%;

[0119] (2) dispersing 0.0133 mol of potassium sulfate in deionized water to obtain a catalyst dispersion, wherein the mass concentration of potassium sulfate after being dissolved in deionized water is controlled to be 15 wt %;

[0120] (3) under N2 protection and at 70-80°C, 5% of the catalyst dispersion was added dropwise to the pre-emulsified liquid to react and obtain a seed solution;

[0121] (4) Under N2 protection, the remaining 95% of the catalyst dispersion and a mixture of 0.8 mol of 4-hydroxybutyl acrylate glycidyl ether, 0.72 mol of diethylene glycol ethyl ether methacrylate, 0.1026 mol of sodium dodecylbenzene sulfonate and 0.0684 mol of polyoxyethylene fatty alcohol ether are added dropwise to the seed solution to carry out a polymerization reaction at a temperature of 70 to 80°C for a reaction time of 4 h. A pH adjuster is added within a range of 7 to 8 to obtain a modified epoxy emulsion A.

[0122] Preparation of modified epoxy curing agent:

[0123] Under N2 protection, at 40°C, 0.9 mol of bisphenol A diglycidyl ether was dispersed and dissolved in propylene glycol methyl ether acetate at a high speed, and the mass concentration was controlled to be 40%. 1 mol of tri(2-aminoethyl)amine was added dropwise, and the temperature was raised to 60-70°C for reaction for 1 hour. 1.1 mol of ethylene glycol diglycidyl was added dropwise and the reaction was continued for 1 hour. The temperature was lowered to room temperature, and propylene glycol methyl ether acetate was added to adjust the solid content of the system to 60%, thereby obtaining the modified epoxy curing agent.

[0124] The preparation method of waterborne epoxy micaceous iron coating is as follows:

[0125] Component A: Use a high-speed disperser to disperse 40% of the water-based epoxy emulsion and the additive component A at a stirring speed of 600-800 r / min for about 30 minutes; then gradually add micaceous iron ash, anti-settling agent, pigments and fillers, and continue to disperse for 60 minutes; add the remaining water-based epoxy emulsion, adjust the stirring speed to 1800-2000 r / min, and disperse for 30 minutes; control the fineness to ≤30μm, filter, and package the material;

[0126] Component B: Direct packaging and use;

[0127] Components A and B are used in a ratio of 9.6:1.

[0128] Example 2

[0129] The raw materials and dosage of component A are as follows:

[0130]

[0131] The raw materials and dosage of component B are as follows:

[0132] Modified epoxy curing agent 100 parts by weight /

[0133] The modified epoxy emulsion B is prepared by the following method:

[0134] (1) Under a N2 atmosphere, 1 mol of isophorone diisocyanate was dispersed at high speed and heated to 60°C, 0.95 mol of dehydrated tripropylene glycol methyl ether was added dropwise, the temperature was raised to 80-90°C, and the reaction was carried out for 1 hour;

[0135] (2) After the temperature drops to 60° C., 0.8 mol of dehydrated 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol is added dropwise, the temperature is raised to 80-90° C., and the reaction is carried out for 1 hour;

[0136] (3) Deionized water was slowly added into the reaction system to adjust the solid content to 40% to obtain the modified epoxy emulsion B.

[0137] The modified epoxy curing agent is prepared by the following method:

[0138] The molar ratio of bisphenol A diglycidyl ether: tris(2-aminoethyl)amine: ethylene glycol diglycidyl ether is 1.1:1:0.9;

[0139] Under N2 protection, at 30°C, 1.1 moles of bisphenol A diglycidyl ether were dispersed and dissolved in propylene glycol methyl ether at a high speed to a concentration of 60%, 1 mole of tri(2-aminoethyl)amine was added dropwise, the temperature was raised to 50-60°C, the reaction was continued for 2 hours, 0.9 moles of ethylene glycol diglycidyl was added dropwise and the reaction was continued for 2 hours, the temperature was lowered to room temperature, and dipropylene glycol butyl ether was added to adjust the solid content of the system to 40%, thereby obtaining the modified epoxy curing agent.

[0140] The preparation method of waterborne epoxy micaceous iron coating is as follows:

[0141] Component A: Use a high-speed disperser to disperse 60% of the water-based epoxy emulsion and the additive component A at a stirring speed of 800-1000 r / min for about 10 minutes; then gradually add micaceous iron ash, anti-settling agent, pigments and fillers, and continue to disperse for 60 minutes; add the remaining water-based epoxy emulsion, adjust the stirring speed to 800-1000 r / min, and disperse for 30 minutes; control the fineness to ≤30μm, filter, and package the material;

[0142] Component B: Direct packaging and use;

[0143] Components A and B are used in a ratio of 11.5:1.

[0144] Example 3

[0145] The raw materials and dosage of component A are as follows:

[0146]

[0147]

[0148] The raw materials and dosage of component B are as follows:

[0149] Modified epoxy curing agent 100 parts by weight /

[0150] The modified epoxy emulsion A is prepared by the following method:

[0151] (1) 0.4 mol of 4-hydroxybutyl acrylate glycidyl ether monomer and 0.42 mol of diethylene glycol ethyl ether methacrylate monomer were mixed, and dispersed with 0.00123 mol of sodium lauryl sulfate and 0.00287 mol of aliphatic glyceride in deionized water to obtain a pre-emulsion;

[0152] The total mass concentration of 4-hydroxybutyl acrylate glycidyl ether monomer and diethylene glycol ethyl ether methacrylate monomer in deionized water is controlled to be 40 wt %;

[0153] (2) dispersing 0.00205 mol of ammonium persulfate in deionized water to obtain a catalyst dispersion, wherein the mass concentration of ammonium sulfate dissolved in deionized water is controlled to be 50 wt %;

[0154] (3) under N2 protection and at 60-70°C, 40% of the catalyst dispersion was added dropwise to the pre-emulsion to obtain a seed solution;

[0155] (4) Under N2 protection, the remaining 60% of the catalyst dispersion and a mixture of 0.6 mol of 4-hydroxybutyl acrylate glycidyl ether, 0.63 mol of diethylene glycol ethyl ether methacrylate, 0.001845 mol of sodium lauryl sulfate and 0.004305 mol of aliphatic glyceride are added dropwise to the seed solution to carry out a polymerization reaction at a polymerization temperature of 80 to 90°C and a reaction time of 0.5 h. A pH adjuster is added to adjust the pH to 10 to 11 to obtain the modified epoxy emulsion A.

[0156] The modified epoxy emulsion B is prepared by the following method:

[0157] (1) Under N2 protection, 1 mol of isophorone diisocyanate was dispersed at high speed and heated to 50°C, 0.8 mol of dehydrated tripropylene glycol methyl ether was added dropwise, the temperature was raised to 80-90°C, and the reaction was carried out for 2 hours;

[0158] (2) After cooling to 50° C., 0.95 mol of dehydrated 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol was added dropwise, and the temperature was raised to 80-90° C. The reaction time was 2 h;

[0159] (3) Slowly adding deionized water into the reaction system to adjust the solid content to 50% to obtain the modified epoxy emulsion B.

[0160] The modified epoxy curing agent is prepared by the following method:

[0161] Under N2 protection, at 35°C, 0.9 mol of bisphenol A diglycidyl ether was dispersed and dissolved in propylene glycol methyl ether acetate at a high speed, and the concentration was controlled to be 50%. 1 mol of tri(2-aminoethyl)amine was added dropwise, and the temperature was raised to 55-65°C for reaction. The reaction time was 1.5 h. 1.1 mol of ethylene glycol diglycidyl was added dropwise and the reaction was continued for 1.5 h. The temperature was lowered to room temperature, and dioxydimethyl ether acetate was added to adjust the solid content of the system to 50%, thereby obtaining the modified epoxy curing agent.

[0162] The preparation method of waterborne epoxy micaceous iron coating is as follows:

[0163] Component A: Use a high-speed disperser to disperse 50% of the water-based epoxy emulsion and the additive component A at a stirring speed of 600-800 r / min for about 15 minutes; then gradually add micaceous iron ash, anti-settling agent, pigments and fillers, and continue to disperse for 40 minutes; add the remaining water-based epoxy emulsion, adjust the stirring speed to 1000-1200 r / min, and disperse for 60 minutes; control the fineness to ≤30μm, filter, and package the material;

[0164] Component B: Direct packaging and use;

[0165] Components A and B are used in a ratio of 10.5:1.

[0166] Example 4

[0167] The raw materials and dosage of component A are as follows:

[0168]

[0169] The raw materials and dosage of component B are as follows:

[0170] Epoxy curing agent Aradur 3986 45 parts by weight Huntsman

[0171] Epoxy curing agent BANCO 900 55 parts by weight Banghe Chemical

[0172] The modified epoxy emulsion A is prepared by the following method:

[0173] (1) 0.15 mol of 4-hydroxybutyl acrylate glycidyl ether monomer and 0.2375 mol of diethylene glycol ethyl ether methacrylate monomer were mixed and dispersed with 0.02925 mol of potassium dodecyl sulfate in deionized water to obtain a pre-emulsion;

[0174] The total mass concentration of 4-hydroxybutyl acrylate glycidyl ether monomer and di(ethylene glycol) ethyl ether methacrylate monomer in deionized water is controlled to be 30wt%;

[0175] (2) dispersing 0.00975 mol of azobisisobutylnitrile in deionized water to obtain a dispersion, wherein the mass concentration of azobisisobutylnitrile after being dissolved in deionized water is controlled to be 30 wt %;

[0176] (3) under N2 protection, at 65-75°C, adding 30% of the catalyst dispersion to the pre-emulsion to react and obtain a seed solution;

[0177] (4) Under N2 protection, the remaining 70% of the catalyst dispersion and a mixture of 0.85 mol of 4-hydroxybutyl acrylate glycidyl ether, 0.7125 mol of diethylene glycol ethyl ether methacrylate, and 0.06825 mol of potassium dodecyl sulfate were added dropwise to the seed solution to carry out a polymerization reaction at a reaction temperature of 75 to 85°C for 2 hours, and a pH adjuster was added to adjust the pH to 9 to 10 to obtain the modified epoxy emulsion A.

[0178] Modified epoxy emulsion B was prepared by the following method:

[0179] (1) Under N2 protection, 1 mol of isophorone diisocyanate was dispersed at high speed and heated to 50-60°C, 0.9 mol of dehydrated tripropylene glycol methyl ether was added dropwise, and the temperature was raised to 80-90°C. The reaction time was 1.5 h;

[0180] (2) cooling to 50-60° C., adding 0.9 mol of dehydrated 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol dropwise, and continuing to heat to 80-90° C. for a reaction time of 1.5 h;

[0181] (3) Deionized water was slowly added into the reaction system to adjust the solid content to 45% to obtain the modified epoxy emulsion B.

[0182] The preparation method of waterborne epoxy micaceous iron coating is as follows:

[0183] Component A: Use a high-speed disperser to disperse 60% of the water-based epoxy emulsion and the additive component A at a stirring speed of 800-1000 r / min for about 20 minutes; then gradually add micaceous iron ash, anti-settling agent, pigments and fillers, and continue to disperse for 50 minutes; add the remaining water-based epoxy emulsion, adjust the stirring speed to 1800-2000 r / min, and disperse for 30 minutes; control the fineness to ≤30μm, filter, and package the material;

[0184] Component B: Mix according to the above amount, use a high-speed disperser, at a stirring speed of 800-1000r / min, disperse for about 30min, filter, and pack the material;

[0185] Components A and B are used in a ratio of 10:1.

[0186] Example 5

[0187] The raw materials and dosage of component A are as follows:

[0188]

[0189]

[0190] The raw materials and dosage of component B are as follows:

[0191] Water-based epoxy curing agent EP1KURE 8290 25 parts by weight American Hanson

[0192] Water-based epoxy curing agent HDH6381 75 parts by weight Han Dai Chemical

[0193] The preparation method of waterborne epoxy micaceous iron coating is as follows:

[0194] Component A: Use a high-speed disperser to disperse 60% of the water-based epoxy emulsion, cosolvent, and additive component A at a stirring speed of 800-1000 r / min for about 20 minutes; then gradually add micaceous iron ash, anti-settling agent, pigments and fillers, and continue to disperse for 40 minutes; add the remaining water-based epoxy emulsion, adjust the stirring speed to 1200-1400 r / min, and disperse for 50 minutes; control the fineness to ≤30μm, filter, and package the material;

[0195] Component B: Mix according to the above amount, use a high-speed disperser, at a stirring speed of 1200-1400r / min, disperse for about 40min, filter, and pack the material;

[0196] Components A and B are used in a ratio of 10.2:1.

[0197] Comparative Example 1

[0198] The comparative example is selected from Chinese patent 201910552763.X, a thick paste low-VOCs water-based epoxy micaceous iron coating and its preparation method, authorization announcement CN 110218503B, authorization announcement date 2021.04.13, and Example 2 therein.

[0199] The preparation of component A comprises the following steps:

[0200] (1) mixing a portion of the first aqueous epoxy emulsion, a portion of the second aqueous epoxy emulsion, an anti-settling agent, a wetting and dispersing agent, and a defoaming agent uniformly;

[0201] (2) adding pigments and fillers and anti-rust pigments to the mixed solution obtained in step (1) and dispersing at high speed until the fineness is less than 60 μm;

[0202] (3) adding the remaining first aqueous epoxy emulsion and the second aqueous epoxy emulsion to the powder obtained in step (2), stirring evenly, adding mica iron oxide ash and dispersing at high speed until the fineness is less than 70 μm;

[0203] (4) adding a substrate wetting agent, a flash rust inhibitor, and a thickener to the mixed solution obtained in step (3), stirring and mixing the mixture to obtain component A;

[0204] The preparation of component B comprises the following steps: encapsulating the water-based amine curing agent to obtain component B.

[0205] The water-based epoxy micaceous iron coatings prepared in Examples 1-5 of the present invention and Comparative Example 1 were tested according to "HG / T4340-2012 Epoxy Micaceous Iron Intermediate Paint", and the test results are shown in Table 1.

[0206] Table 1

[0207]

[0208] It can be seen from the test results of the above-mentioned Examples 1 to 4 and Comparative Example 1 that the waterborne epoxy micaceous iron coating provided by the present invention has excellent anti-settling, anti-sagging, high adhesion, and high single-coat paint film thickness, and can be used in the fields of construction, industry, petrochemicals, etc. The waterborne epoxy micaceous iron coating of the present invention preferably has a modified curing agent and emulsion system that are superior to the reference document in terms of anti-sagging, adhesion, drying time, salt spray resistance, and impact resistance; and the present invention optimizes and adjusts the structure of the film-forming material of the curing agent and emulsion system, and has high anti-corrosion efficiency; water is selected as a diluent, and the construction is green, environmentally friendly, and pollution-free.

Claims

1. A water-based epoxy micaceous iron coating, characterized in that The water-based epoxy micaceous iron coating comprises a component A and a component B, wherein the component A and the component B are prepared from raw materials comprising the following components respectively: Component A includes water-based epoxy emulsion, micaceous iron ash, anti-settling agent, pigments and fillers, and additive A; Component B is a water-based epoxy curing agent; The A component is calculated by weight: The weight ratio of component A to component B is (8-12):

1.

2. The water-based epoxy micaceous iron coating according to claim 1, characterized in that: The A component is calculated by weight: The weight ratio of component A to component B is (9.5-11.5):

1.

3. The water-based epoxy micaceous iron coating according to claim 1, characterized in that: The aqueous epoxy emulsion is at least one of bisphenol A epoxy emulsion, bisphenol F epoxy emulsion, acrylic epoxy emulsion, modified epoxy emulsion A, and modified epoxy emulsion B; and / or, The mesh size of the micaceous iron ash is 400-800 mesh; and / or, The anti-settling agent is at least one of organic bentonite, attapulgite, lithium magnesium silicate, wax powder, wax powder dispersion, and fumed silica; and / or, The pigment filler is at least one of phosphate anti-rust pigment, kaolin, talc, mica powder, wollastonite powder, precipitated barium sulfate, titanium dioxide, silicon powder, composite iron titanium powder, heavy calcium carbonate, light calcium carbonate, activated calcium carbonate, calcite powder, dolomite powder, quartz powder, and feldspar powder; and / or, The auxiliary agent A is at least one of a dispersant, a thickener, a wetting agent, a defoamer, a leveling agent, a pH adjuster, an adhesion promoter, a flash rust preventer, and a corrosion inhibitor; and / or, The waterborne epoxy curing agent is an amine curing agent; preferably, the amine curing agent is at least one of a fatty amine curing agent, alicyclic amine curing agent, phenolic amine curing agent, polyamide curing agent, and modified epoxy curing agent.

4. The water-based epoxy micaceous iron coating according to claim 3, characterized in that: The molecular structural formula of the modified epoxy emulsion A is: Wherein n is any integer between 100 and 150; Preferably, The modified epoxy emulsion A is prepared by emulsion polymerization of raw materials including the following components: 4-Hydroxybutyl acrylate glycidyl ether, di(ethylene glycol)ethyl ether methacrylate, catalyst, emulsifier and deionized water; Further preferably, the molar ratio of 4-hydroxybutyl acrylate glycidyl ether to di(ethylene glycol)ethyl ether methacrylate is 1:(0.8-1.2), preferably 1:(0.9-1.05); and / or, The molar ratio of the catalyst to the total amount of 4-hydroxybutyl acrylate glycidyl ether and di(ethylene glycol)ethyl ether methacrylate is (0.1-0.7):100; and / or, The molar ratio of the emulsifier to the total amount of 4-hydroxybutyl acrylate glycidyl ether and di(ethylene glycol) ethyl ether methacrylate is (0.5-10):100; More preferably, the catalyst is at least one of ammonium persulfate, potassium persulfate, azobisisobutylnitrile, azobisisoheptylnitrile, azobisisobutylamidine hydrochloride, and azobisisobutylimidazoline hydrochloride; and / or, The emulsifier is an anionic emulsifier or a nonionic emulsifier; The anionic emulsifier is an alkyl salt, preferably at least one of sodium dodecylbenzene sulfonate, sodium dodecyl sulfate, potassium dodecyl sulfate, dodecyltrimethylammonium bromide, alkyl vinyl sulfonate, and sodium allyl ether hydroxypropyl sulfonate; The nonionic emulsifier is at least one of aliphatic glyceride, polyol emulsifier, polyoxyethylene fatty alcohol ether, and polyoxyethylene polyoxypropylene copolymer.

5. The water-based epoxy micaceous iron coating according to claim 4, characterized in that: The modified epoxy emulsion A is prepared by the following method: (1) mixing part of 4-hydroxybutyl acrylate glycidyl ether monomer and part of diethylene glycol ethyl ether methacrylate monomer, and dispersing the mixture with part of emulsifier in deionized water to obtain a pre-emulsion; The part of 4-hydroxybutyl acrylate glycidyl ether monomer accounts for 10-40% of the total mass of 4-hydroxybutyl acrylate glycidyl ether monomer; The part of di(ethylene glycol) ethyl ether methacrylate monomer accounts for 10-40% of the total mass of di(ethylene glycol) ethyl ether methacrylate monomer; The partial emulsifier accounts for 5-40% of the total mass of the emulsifier; The mass concentration of the total mass of the part of 4-hydroxybutyl acrylate glycidyl ether monomer and the part of di(ethylene glycol) ethyl ether methacrylate monomer in deionized water is 20-40wt%; (2) dispersing the catalyst in deionized water to obtain a catalyst dispersion; The mass concentration of the catalyst after being dissolved in deionized water is 15 to 50 wt %; (3) under a protective gas atmosphere at 60-80° C., adding a portion of the catalyst dispersion to the pre-emulsified liquid to react to obtain a seed solution; The part of the catalyst dispersion accounts for 5-40% of the total mass of the catalyst dispersion; (4) under a protective gas atmosphere, adding the remaining catalyst dispersion, the remaining 4-hydroxybutyl acrylate glycidyl ether, the remaining diethylene glycol ether methacrylate, and the remaining emulsifier to the seed solution, performing a polymerization reaction, and adding a pH adjuster to obtain the modified epoxy emulsion A; The polymerization reaction temperature is 70-90° C., the reaction time is 0.5-4 hours, and the pH adjustment range is 7-11.

6. The water-based epoxy micaceous iron coating according to claim 3, characterized in that: The molecular structural formula of the modified epoxy emulsion B is: Preferably, The modified epoxy emulsion B is prepared from raw materials including the following components: Isophorone diisocyanate, tripropylene glycol methyl ether, and 3-(oxiranylmethoxy)-2,2-bis[(oxiranylmethoxy)methyl]propanol; The molar ratio of isophorone diisocyanate, tripropylene glycol methyl ether and 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol is 1:(0.7-1):(0.7-1); preferably 1:(0.8-0.95):(0.8-0.95).

7. The water-based epoxy micaceous iron coating according to claim 6, characterized in that: The modified epoxy emulsion B is prepared by the following method: (1) in a protective gas atmosphere, isophorone diisocyanate is dispersed at high speed and heated, dehydrated tripropylene glycol methyl ether is added dropwise, and the temperature is raised to react; The isophorone diisocyanate is heated to 50-60°C, the temperature of the temperature rise reaction is 80-90°C, and the reaction time is 1-2h; (2) after cooling, add dehydrated 3-(oxiranylmethoxy)-2,2-di[(oxiranylmethoxy)methyl]propanol dropwise, and continue to heat the reaction; The cooling temperature is 50-60°C, the heating reaction temperature is 80-90°C, and the reaction time is 1-2h; (3) slowly adding deionized water into the reaction system to adjust the solid content to obtain the modified epoxy emulsion B; The solid content is 40-50%.

8. The water-based epoxy micaceous iron coating according to claim 3, characterized in that: The molecular structural formula of the modified epoxy curing agent is: Wherein n is any integer from 1 to 10; Preferably, The modified epoxy curing agent is prepared from raw materials including the following components: Bisphenol A diglycidyl ether, tris(2-aminoethyl)amine, and ethylene glycol diglycidyl ether; The molar ratio of bisphenol A diglycidyl ether: tris(2-aminoethyl)amine: ethylene glycol diglycidyl ether is (0.8-1.2):1:(0.8-1.2); preferably (0.9-1.1):1:(0.9-1.1); Preferably, The modified epoxy curing agent is prepared by the following method: In a protective gas atmosphere, bisphenol A diglycidyl ether is dispersed and dissolved in an organic solvent at a constant temperature at high speed, tri(2-aminoethyl)amine is added dropwise, the temperature is raised to react, ethylene glycol diglycidyl is added dropwise to continue the reaction, the temperature is lowered to room temperature, a co-solvent is added to adjust the solid content of the system, and the modified epoxy curing agent is obtained; More preferably, the constant temperature is 30-40° C., the concentration of bisphenol A diglycidyl ether dissolved in the organic solvent is 40-60%, the temperature of the temperature rise reaction is 50-70° C., the reaction time is 1-2 hours, ethylene glycol diglycidol is added dropwise and the reaction is continued for 1-2 hours, and the solid content is 40-60%; The solvent is at least one of alcohol ether, alcohol ester, alcohol, acid ester and ether ester; further preferably, the cosolvent is at least one of ethylene glycol methyl ether, ethylene glycol ethyl ether, ethylene glycol propyl ether, ethylene glycol butyl ether, ethylene glycol tert-butyl ether, ethylene glycol butyl ether acetate, ethylene glycol diacetate, diethylene glycol butyl ether, diethylene glycol tert-butyl ether, propylene glycol, propylene glycol methyl ether, propylene glycol methyl ether acetate, propylene glycol ethyl ether, propylene glycol n-propyl ether, propylene glycol butyl ether, propylene glycol dioic acid acetate, propylene glycol phenyl ether, dipropylene glycol methyl ether, dipropylene glycol butyl ether, isopropyl alcohol, dibasic acid ester, alcohol ester dodecahydrate, and dioxydimethyl ether acetate.

9. A method for preparing a waterborne epoxy micaceous iron coating as claimed in any one of claims 1 to 8, characterized in that The method comprises: The components of component A are mixed according to the weight parts to obtain the component A; and the water-based epoxy micaceous iron coating is obtained by mixing component A and component B according to the dosage ratio.

10. Use of the waterborne epoxy micaceous iron coating as claimed in any one of claims 1 to 8 in the field of corrosion protection.

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