Waterborne epoxy anticorrosive primer as well as preparation method and application thereof

Abstract

The invention discloses a waterborne epoxy anticorrosive primer as well as a preparation method and application thereof. The waterborne epoxy anticorrosive primer comprises a component A and a component B, the mass ratio of the component A to the component B is (3-7): 1; the component A comprises the following preparation raw materials: waterborne epoxy resin, a filler, an auxiliary agent and water; the component B is prepared from the following raw materials: a waterborne epoxy curing agent, a cosolvent and a flash rust resisting agent. The waterborne epoxy anticorrosive primer can be suitable for surface coating of various base materials such as carbon steel, aluminum alloy and electrophoresis base materials. Particularly, when the base material appears on an equipment workpiece at the same time, the universality is high, and the spraying process can be effectively reduced. The water-based paint product has excellent adhesive force and corrosion resistance, and does not contain a low-volatility and high-toxicity solvent. In addition, the waterborne epoxy anticorrosive primer has high compatibility with the flash-rust-resistant agent, and the addition of the high-content flash-rust-resistant agent can be realized in a high-humidity environment.

Description

Technical Field

[0001] The present invention belongs to the technical field of coatings, and in particular relates to a waterborne epoxy anticorrosive primer and a preparation method and application thereof. Background Art

[0002] Solvent-based epoxy primers, due to their excellent adhesion and salt spray resistance, are widely used as traditional anti-corrosion primers in applications such as rail transit, construction machinery, buses, and automotive parts. However, their formulations require a large amount of solvent to facilitate production and adjust application performance. Existing water-based epoxy primers, while offering the same excellent adhesion and salt spray resistance as solvent-based epoxy primers, have been widely used in substrate coating. However, the introduction of hydrophilic groups to improve the hydrophilicity of water-based epoxy resins and curing agents places higher demands on the selection and combination of materials in the formulation. Most water-based epoxy primers cannot be applied simultaneously to different substrates, such as aluminum alloys and electrophoretic coatings. In the anti-corrosion primer coating of passenger cars, buses, and other vehicles, multiple substrates may coexist. Most existing water-based epoxy two-component primers are only suitable for one type of substrate, such as aluminum alloys or electrophoretic coatings. Furthermore, due to differences in the processes and formulations of electrophoretic coating suppliers, the adhesion of electrophoretic coatings to water-based epoxy primers varies significantly, creating a risk of entire coatings falling off.

[0003] In addition, when water-based paint is sprayed on the surface of a metal substrate, flash rusting will occur, resulting in a decrease in the overall performance of the paint film. Therefore, it is necessary to add an anti-flash rust agent. The content of common anti-flash rust agents in the curing agent system of anti-corrosion primers is 0.5-1.5%wt. However, in a high humidity environment, the anti-rust performance of the anti-flash rust agent is required to be higher. When the content of the anti-flash rust agent is increased, the anti-flash rust agent and the epoxy curing agent often undergo phase separation, which brings great troubles to production and processing. Therefore, it is necessary to develop a universal water-based epoxy primer with high compatibility with anti-flash rust agents, which can be applied to different substrates such as aluminum alloys and electrophoresis, as well as in high humidity environments, in order to reduce the development and maintenance costs of the formula. Summary of the Invention

[0004] To overcome the problems of the prior art, one object of the present invention is to provide a waterborne epoxy anticorrosive primer. A second object of the present invention is to provide a method for preparing the waterborne epoxy anticorrosive primer. A third object of the present invention is to provide applications of the waterborne epoxy anticorrosive primer.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is:

[0006] A first aspect of the present invention provides a waterborne epoxy anticorrosive primer, comprising component A and component B; the components A and B are composed in a mass ratio of (3-7):1; the component A comprises the following raw materials in parts by mass: 45-60 parts of a waterborne epoxy resin, 10-25 parts of a filler, 5-25 parts of an additive, and 8-15 parts of water; the component B comprises the following raw materials in parts by mass: 14-20 parts of a waterborne epoxy curing agent, 2-5 parts of a cosolvent, and 0.5-1.5 parts of an anti-flash rust agent; the active hydrogen equivalent of the waterborne epoxy curing agent is 300-450 g / eq.

[0007] The active hydrogen equivalent refers to the molecular weight corresponding to each active hydrogen in the amine curing agent, and is usually used to calculate the amount of epoxy resin curing agent.

[0008] Preferably, the component A and the component B are composed in a mass ratio of (4-6):1.

[0009] More preferably, the component A and component B are composed in a mass ratio of 4:1, 5:1 or 6:1.

[0010] Preferably, the waterborne epoxy resin has an epoxy equivalent of 900-1100 g / mol and a viscosity of 200-6000 cP at 25°C.

[0011] The test method for epoxy equivalent is ASTM D1652.

[0012] The viscosity is tested according to ASTM D2196.

[0013] More preferably, the waterborne epoxy resin includes at least one of Guangzhou Lingwei JT-WBE511, JT-WBE521, JT-WBE522, JT-WBE523, and Huntsman PZ3961-1.

[0014] Preferably, the waterborne epoxy curing agent includes a waterborne epoxy curing agent 1 and a waterborne epoxy curing agent 2; the active hydrogen equivalent of the waterborne epoxy curing agent 1 is 330 to 370 g / eq, and the active hydrogen equivalent of the waterborne epoxy curing agent 2 is 400 to 450 g / eq.

[0015] Preferably, the viscosity of the waterborne epoxy curing agent at 25° C. is 10,000-50,000 cP.

[0016] More preferably, the waterborne epoxy curing agent 1 includes Guangzhou Lingwei JT-WBH816, and the waterborne epoxy curing agent 2 includes at least one of Huntsman Aradur 3986 and Guangzhou Lingwei JT-WBH818.

[0017] More preferably, when the waterborne epoxy curing agent includes Guangzhou Lingwei JT-WBH816 and JT-WBH818, the mass ratio of JT-WBH816 to JT-WBH818 is (0.25-1.25):1.

[0018] Further preferably, the mass ratio of JT-WBH816 to JT-WBH818 is (0.5-1.25):1.

[0019] More preferably, the mass ratio of JT-WBH816 to JT-WBH818 is (0.7-1):1.

[0020] Preferably, the filler is one or more of titanium dioxide, ZJ05D natural barium sulfate, MS-1250 mesh talc, wollastonite, and MA100 carbon black.

[0021] Preferably, the additives include at least one of anti-rust pigments, film-forming aids, anti-settling agents, wetting and dispersing agents, water-based defoaming agents, substrate wetting agents, adhesion promoters, and polyurethane thickeners.

[0022] More preferably, the anti-rust pigment is selected from phosphate-based anti-rust pigments and / or chromate-based anti-rust pigments.

[0023] Further preferably, the anti-rust pigment is selected from Hesanhong SHA218, SHA4, Hangzhou Stan STENICPHOS ZA, P-SR, Halox SW111, At least one of the LM60.

[0024] More preferably, the film-forming aid is selected from propylene glycol ether film-forming aids and / or ethylene glycol ether film-forming aids.

[0025] Further preferably, the film-forming aid is selected from at least one of dipropylene glycol butyl ether (DPNB), propylene glycol methyl ether (PM), dipropylene glycol methyl ether (DPM), propylene glycol butyl ether (PNB), ethylene glycol butyl ether (BCS), and diethylene glycol butyl ether (DB).

[0026] More preferably, the anti-settling agent is selected from at least one of an organic wax anti-settling agent, an organic modified bentonite anti-settling agent, and a silica anti-settling agent.

[0027] Further preferably, the anti-settling agent is selected from BP-188L, RHEOBYK-420, At least one of 200 gas silicon.

[0028] More preferably, the wetting and dispersing agent is selected from at least one of a polymer block copolymer type solvent-based dispersant, a polymer water-based dispersant, and a high molecular weight polyester / acrylate type solvent-based dispersant.

[0029] Further preferably, the wetting and dispersing agent is at least one selected from BYK 190, BYK 194N, TEGO 757W, and ALLNEX 6208.

[0030] More preferably, the aqueous defoamer is selected from at least one of a mineral oil-based defoamer, a polyether silicone defoamer, and an acetylene glycol defoamer.

[0031] Further preferably, the aqueous defoaming agent is selected from Airex 901W, Airex 902W, Foamex 810, Foamex 845, At least one of 104E.

[0032] More preferably, the substrate wetting agent is a polyether-modified polysiloxane wetting agent.

[0033] Further preferably, the substrate wetting agent is selected from at least one of TEGO 270, BYK 346, BYK 348, TWIN 4000, and TWIN 4100.

[0034] More preferably, the adhesion promoter is an epoxy silane oligomer type adhesion promoter.

[0035] Further preferably, the adhesion promoter is CoatOSil MP200.

[0036] More preferably, the polyurethane thickener is a nonionic polyurethane associative thickener.

[0037] Further preferably, the polyurethane thickener is selected from 299, At least one of Gel 0620.

[0038] More preferably, the A component includes the following raw materials in parts by mass: 45-60 parts of water-based epoxy resin, 3-12 parts of anti-rust pigment, 10-25 parts of filler, 1-4 parts of film-forming aid, 0.1-0.5 parts of anti-settling agent, 1-2 parts of wetting and dispersing agent, 0.1-0.5 parts of water-based defoaming agent, 0.2-0.7 parts of substrate wetting agent, 0.5-1.0 parts of adhesion promoter, 0.5-1.5 parts of polyurethane thickener, and 8-15 parts of water.

[0039] Further preferably, the A component is prepared from the following raw materials in the following mass percentages: 45.0-55.0% water-based epoxy resin, 5.0-7.5% anti-rust pigment, 20.0-25.0% filler, 1.0-4.0% film-forming aid, 0.15-0.5% anti-settling agent, 1.2-1.6% wetting dispersant, 0.2-1.0% water-based defoamer, 0.2-0.5% substrate wetting agent, 0.5-1.0% adhesion promoter, 0.3-1.0% polyurethane thickener, and 10-16% water.

[0040] Preferably, the cosolvent is an alcohol ether cosolvent.

[0041] More preferably, the cosolvent is selected from at least one of propylene glycol methyl ether (PM), dipropylene glycol methyl ether (DPM), ethylene glycol butyl ether (BCS), and diethylene glycol butyl ether (DB).

[0042] Preferably, the anti-flash rust agent is one of an organic zinc chelate anti-flash rust agent and a sodium nitrite anti-flash rust agent, or a combination thereof.

[0043] More preferably, the anti-flash rust agent is selected from Raybo 60, One or a combination of FA179.

[0044] Preferably, in the raw materials for preparing component B, the mass percentage of the anti-flash rust agent is 3-5.0%.

[0045] More preferably, the B component is prepared from the following raw materials in the following mass percentages: 56.0-72.0% of waterborne epoxy curing agent, 6.0-15.0% of cosolvent, 3-5.0% of anti-flash rust agent, and 10.0-20.0% of water.

[0046] The second aspect of the present invention provides a method for preparing the waterborne epoxy anticorrosive primer described in the first aspect, comprising the following steps: mixing the raw materials for preparing component A to obtain component A, mixing the raw materials for preparing component B to obtain component B, and then mixing component A and component B to obtain a waterborne epoxy anticorrosive primer.

[0047] Preferably, the mixing process of component A comprises the following steps: first, stirring and mixing part of the water, wetting dispersant, water-based defoamer, anti-settling agent, anti-rust pigment, and filler and grinding to obtain a water-ground slurry; then stirring and mixing the water-based epoxy resin, film-forming aid, water-based defoamer, adhesion promoter, substrate wetting agent, and remaining water with the water-ground slurry; and adding a polyurethane thickener to adjust the viscosity while stirring to obtain component A.

[0048] The third aspect of the present invention provides the use of the waterborne epoxy anticorrosive primer described in the first aspect in preparing a metal substrate coating. The beneficial effects of the present invention are:

[0049] The present invention provides a water-based epoxy anti-corrosion primer, which can be applied to the surface coating of various substrate materials such as carbon steel, aluminum alloy and electrophoretic substrate. In particular, when the above-mentioned substrates appear on a piece of equipment at the same time, the versatility is strong and the spraying process can be effectively reduced. The present invention is a water-based coating product, which, in addition to the above-mentioned excellent adhesion and corrosion resistance, does not contain low-volatile, highly toxic solvents such as benzene, lipids, and ketones. In addition, the water-based epoxy anti-corrosion primer of the present invention has high compatibility with anti-flash rust agents, and can achieve the addition of high-content anti-flash rust agents in response to high humidity environments. DETAILED DESCRIPTION

[0050] The present invention is further described in detail below through specific examples. Unless otherwise specified, the raw materials used in the following examples can be obtained from conventional commercial sources or prepared and isolated by simple synthesis; unless otherwise specified, the processes used are conventional processes in the art.

[0051] Example 1

[0052] This embodiment 1 provides a water-based epoxy anti-corrosion primer suitable for multiple substrates such as aluminum alloy and electrophoresis, which is composed of component A and component B in a weight ratio of 100:25, wherein component A is prepared from the following raw materials in the following weight percentages:

[0053] (1) Deionized water 14.0%

[0054] (2) BYK-190 wetting and dispersing agent 1.2%

[0055] (3) 104E water-based defoamer 0.5%

[0056] (4) BP-188L anti-settling agent 0.3%

[0057] (5) Hesanhong SHA218 anti-rust pigment 5.0%

[0058] (6) R706 titanium dioxide filler 8.0%

[0059] (7) MA100 carbon black filler 0.1%

[0060] (8) MS-1250 mesh talc filler 13.0%

[0061] (9) Guangzhou Lingwei JT-WBE511 water-based epoxy resin 55.0%

[0062] (10) DPNB dipropylene glycol butyl ether film-forming aid 1.2%

[0063] (11) Twin 4100 wetting and defoaming agent 0.2%

[0064] (12) CoatOSil MP200 adhesion promoter 0.6%

[0065] (13) BYK 348 substrate wetting agent 0.3%

[0066] (14) Deionized water 0.3%

[0067] (15) Gel 0620 thickener 0.3%

[0068] (16) Total: 100.0

[0069] Component B is made from the following raw materials in weight percentage:

[0070] (1) Guangzhou Lingwei JT-WBH816 water-based epoxy curing agent 34.6%

[0071] (2) Guangzhou Lingwei JT-WBH818 water-based epoxy curing agent 41.1%

[0072] (3) PM propylene glycol methyl ether cosolvent 12.0%

[0073] (4) Raybo 60 anti-flash rust agent 4.0%

[0074] (5) Deionized water 8.3%

[0075] (6) Total: 100.0

[0076] The preparation method of the waterborne epoxy anticorrosive primer is as follows:

[0077] (1) The preparation method of component A is as follows:

[0078] (1.1) Preparation of water-grinded slurry: Add the above-mentioned deionized water, wetting dispersant, water-based defoamer, anti-settling agent, anti-rust pigment, and filler into a dispersion tank, stir and disperse at 600-800 rpm for 30 minutes, and grind in a horizontal grinder to a fineness of ≤20 μm before discharging;

[0079] (1.2) Add the above water-ground slurry into a dispersion tank, and add water-based epoxy resin, film-forming aid, water-based defoamer, adhesion promoter, substrate wetting agent, and deionized water in the order and proportion while stirring;

[0080] (1.3) Add polyurethane thickener in proportion while stirring to adjust the viscosity, and test the fineness to ensure that the material is qualified before discharging.

[0081] (2) The preparation method of component B is as follows:

[0082] Put the above water-based epoxy curing agent into the dispersion tank in proportion, add the cosolvent, anti-flash rust agent and deionized water in order and proportion while stirring, stir at 600-800 rpm, stir for 30 minutes, test the fineness and discharge the material if it is qualified.

[0083] (3) Component A and component B prepared according to the above waterborne epoxy anticorrosive primer are mixed uniformly according to the weight ratio, and then 5-10% deionized water is added to prepare the waterborne epoxy anticorrosive primer.

[0084] Example 2

[0085] This embodiment 2 provides a water-based epoxy anti-corrosion primer suitable for multiple substrates such as aluminum alloy and electrophoresis, which is composed of component A and component B in a weight ratio of 100:25, wherein component A is prepared from the following raw materials in the following weight percentages:

[0086] (1) Deionized water 12.0%

[0087] (2) TEGO 757W wetting and dispersing agent 1.4%

[0088] (3) 104E water-based defoamer 0.35%

[0089] (4) Foamex 810 aqueous defoamer 0.15%

[0090] (5) BP-188L anti-settling agent 0.2%

[0091] (6) STENICPHOS ZA anti-rust pigment 5.0%

[0092] (7) Halox SW111 anti-rust pigment 2.0%

[0093] (8) R706 titanium dioxide filler 8.0%

[0094] (9) MA100 carbon black filler 0.1%

[0095] (10) ZJ05D natural barium sulfate filler 5.0%

[0096] (11) MS-1250 mesh talc filler 8.0%

[0097] (12) Guangzhou Lingwei JT-WBE521 water-based epoxy resin 55.0%

[0098] (13) DPNB dipropylene glycol butyl ether film-forming aid 1.2%

[0099] (14) Twin 4100 wetting and defoaming agent 0.2%

[0100] (15) CoatOSil MP200 adhesion promoter 0.6%

[0101] (16) BYK 348 substrate wetting agent 0.3%

[0102] (17) Deionized water 0.2%

[0103] (17) Gel 0620 thickener 0.3%

[0104] (18) Total: 100.0

[0105] Component B is made from the following raw materials in weight percentage:

[0106] (1) Guangzhou Lingwei JT-WBH816 water-based epoxy curing agent 31.5%

[0107] (2) Guangzhou Lingwei JT-WBH818 water-based epoxy curing agent 37.5%

[0108] (3) PM propylene glycol methyl ether cosolvent 8.0%

[0109] (4) DPM dipropylene glycol methyl ether cosolvent 8.0%

[0110] (5) Raybo 60 anti-flash rust agent 4.0%

[0111] (6) Deionized water 11.0%

[0112] (7) Total: 100.0

[0113] The preparation method of the waterborne epoxy anticorrosive primer is the same as that of Example 1.

[0114] Example 3

[0115] This embodiment 3 provides a water-based epoxy anti-corrosion primer suitable for multiple substrates such as aluminum alloy and electrophoresis, which is composed of component A and component B in a weight ratio of 100:25, wherein component A is prepared from the following raw materials in the following weight percentages:

[0116] (1) Deionized water 12.0%

[0117] (2) BYK 194N wetting and dispersing agent 1.4%

[0118] (3) 104E water-based defoamer 0.35%

[0119] (4) Foamex 810 aqueous defoamer 0.15%

[0120] (5) BP-188L anti-settling agent 0.15%

[0121] (6) P-SR anti-rust pigment 3.2%

[0122] (7) Hesanhong SHA218 anti-rust pigment 5.0%

[0123] (8) Halox SW111 anti-rust pigment 2.0%

[0124] (9) R706 titanium dioxide filler 8.0%

[0125] (10) MA100 carbon black filler 0.1%

[0126] (11) ZJ05D natural barium sulfate filler 7.5%

[0127] (12) MS-1250 mesh talc filler 6.5%

[0128] (13) Guangzhou Lingwei JT-WBE521 water-based epoxy resin 48.0%

[0129] (14) DPNB dipropylene glycol butyl ether film-forming aid 1.5%

[0130] (15) Twin 4100 wetting and defoaming agent 0.2%

[0131] (16) CoatOSil MP200 adhesion promoter 0.6%

[0132] (17) BYK 348 substrate wetting agent 0.3%

[0133] (18) Deionized water 2.75%

[0134] (18) Gel 0620 thickener 0.3%

[0135] (19) Total: 100.0

[0136] Component B is made from the following raw materials in weight percentage:

[0137] (1) Guangzhou Lingwei JT-WBH816 water-based epoxy curing agent 31.5%

[0138] (2) Guangzhou Lingwei JT-WBH818 water-based epoxy curing agent 37.5%

[0139] (3) PM propylene glycol methyl ether cosolvent 8.0%

[0140] (4) DPM dipropylene glycol methyl ether cosolvent 8.0%

[0141] (5) Raybo 60 anti-flash rust agent 4.0%

[0142] (6) Deionized water 11.0%

[0143] (7) Total: 100.0

[0144] The preparation method of the waterborne epoxy anticorrosive primer is the same as that of Example 1.

[0145] Comparative Example 1

[0146] This comparative example 1 provides a water-based epoxy anticorrosive primer, which is composed of component A and component B in a weight ratio of 100:25, wherein component A is prepared from the following raw materials in the following weight percentages:

[0147] (1) Deionized water 12.0%

[0148] (2) BYK 194N wetting and dispersing agent 1.4%

[0149] (3) 104E water-based defoamer 0.35%

[0150] (4) Foamex 810 aqueous defoamer 0.15%

[0151] (5) BP-188L anti-settling agent 0.15%

[0152] (6) P-SR anti-rust pigment 3.2%

[0153] (7) Hesanhong SHA218 anti-rust pigment 5.0%

[0154] (8) Halox SW111 anti-rust pigment 2.0%

[0155] (9) R706 titanium dioxide filler 8.0%

[0156] (10) MA100 carbon black filler 0.1%

[0157] (11) ZJ05D natural barium sulfate filler 7.5%

[0158] (12) MS-1250 mesh talc filler 6.5%

[0159] (13) Guangzhou Lingwei JT-WBE521 water-based epoxy resin 48.0%

[0160] (14) DPNB dipropylene glycol butyl ether film-forming aid 1.5%

[0161] (15) Twin 4100 wetting and defoaming agent 0.2%

[0162] (16) CoatOSil MP200 adhesion promoter 0.6%

[0163] (17) BYK 348 substrate wetting agent 0.3%

[0164] (18) Deionized water 2.75%

[0165] (19) Gel 0620 thickener 0.3%

[0166] (20) Total: 100.0

[0167] Component B is made from the following raw materials in weight percentage:

[0168] (1) Guangzhou Lingwei JT-WBH816 water-based epoxy curing agent 12.6%

[0169] (2) Guangzhou Lingwei JT-WBH818 water-based epoxy curing agent 59.7%

[0170] (3) PM propylene glycol methyl ether cosolvent 8.0%

[0171] (4) DPM dipropylene glycol methyl ether cosolvent 8.0%

[0172] (5) Raybo 60 anti-flash rust agent 4.0%

[0173] (6) Deionized water 7.7%

[0174] (7) Total: 100.0

[0175] The preparation method of the waterborne epoxy anticorrosive primer is the same as that of Example 1.

[0176] Comparative Example 2

[0177] Comparative Example 2 provides a water-based epoxy anticorrosive primer, which is composed of component A and component B in a weight ratio of 100:25, wherein component A is prepared from the following raw materials in the following weight percentages:

[0178] (1) Deionized water 12.0%

[0179] (2) BYK 194N wetting and dispersing agent 1.4%

[0180] (3) 104E water-based defoamer 0.35%

[0181] (4) Foamex 810 aqueous defoamer 0.15%

[0182] (5) BP-188L anti-settling agent 0.15%

[0183] (6) P-SR anti-rust pigment 3.2%

[0184] (7) Hesanhong SHA218 anti-rust pigment 5.0%

[0185] (8) Halox SW111 anti-rust pigment 2.0%

[0186] (9) R706 titanium dioxide filler 8.0%

[0187] (10) MA100 carbon black filler 0.1%

[0188] (11) ZJ05D natural barium sulfate filler 7.5%

[0189] (12) MS-1250 mesh talc filler 6.5%

[0190] (13) Guangzhou Lingwei JT-WBE521 water-based epoxy resin 48.0%

[0191] (14) DPNB dipropylene glycol butyl ether film-forming aid 1.5%

[0192] (15) Twin 4100 wetting and defoaming agent 0.2%

[0193] (16) CoatOSil MP200 adhesion promoter 0.6%

[0194] (17) BYK 348 substrate wetting agent 0.3%

[0195] (18) Deionized water 2.75%

[0196] (19) Gel 0620 thickener 0.3%

[0197] (20) Total: 100.0

[0198] Component B is made from the following raw materials in weight percentage:

[0199] (1) Guangzhou Lingwei JT-WBH818 water-based epoxy curing agent 74.7%

[0200] (2) PM propylene glycol methyl ether cosolvent 8.0%

[0201] (3) DPM dipropylene glycol methyl ether cosolvent 8.0%

[0202] (4) Raybo 60 anti-flash rust agent 4.00%

[0203] (5) Deionized water 5.3%

[0204] (6) Total: 100.0

[0205] The preparation method of the waterborne epoxy anticorrosive primer is the same as that of Example 1.

[0206] Performance Testing

[0207] The waterborne epoxy anticorrosive primers of the above examples and comparative examples were sprayed on different substrates and leveled at 25°C for 30 minutes to perform performance tests. The test results are shown in Table 1 below:

[0208] Table 1 Primer test results

[0209]

[0210]

[0211] By comparing Examples 1-3 and Comparative Example 1-2, it can be seen that Examples 1-3 adopt the method of compounding JT-WBH816 and JT-WBH818 curing agents, and the resulting primer is suitable for surface coating of various substrate materials such as carbon steel, aluminum alloy and electrophoretic substrate, while the mass ratio of the curing agent compounding in Comparative Example 1 is not appropriately matched, and no curing agent compounding is adopted in Comparative Example 2. The resulting primer has unstable adhesion on aluminum alloy and electrophoretic substrate, and some suppliers have no adhesion.

[0212] In the organic solvent resistance test, the primers of Examples 1-3 have a high degree of crosslinking and excellent solvent resistance, indicating that the coatings can withstand the stress in subsequent processing.

[0213] In the curing agent stability test, the primers of Examples 1-3 passed the test, indicating that the mixed use of JT-WBH816 and JT-WBH818 not only improves the overall performance of the overall formulation, but also solves the problem of insufficient addition of JT-WBH818 anti-flash rust agent. Laboratory tests also showed that after the two were mixed and stored at 50°C for 14 days, there was no abnormal compatibility, and no flocculation, precipitation, or delamination. In high humidity environments, high levels of anti-flash rust agent can be added. However, phase separation occurred in Comparative Examples 1-2, making it impossible to add high levels of anti-flash rust agent.

[0214] The above is a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications are also considered to be within the scope of protection of the present invention.

Claims

1. A waterborne epoxy anticorrosive primer, characterized in that: The invention comprises component A and component B; the component A and component B are composed in a mass ratio of (3-7):1; the component A comprises the following raw materials in parts by mass: 45-60 parts of a waterborne epoxy resin, 10-25 parts of a filler, 5-25 parts of an additive, and 8-15 parts of water; the component B comprises the following raw materials in parts by mass: 14-20 parts of a waterborne epoxy curing agent, 2-5 parts of a cosolvent, and 0.5-1.5 parts of an anti-flash rust agent; and the active hydrogen equivalent of the waterborne epoxy curing agent is 300-450 g / eq.

2. The waterborne epoxy anticorrosive primer according to claim 1, characterized in that: The waterborne epoxy resin has an epoxy equivalent of 900-1100 g / mol and a viscosity of 200-6000 cP at 25°C; Preferably, the waterborne epoxy resin includes at least one of Guangzhou Lingwei JT-WBE511, JT-WBE521, JT-WBE522, JT-WBE523, and Huntsman PZ3961-1.

3. The waterborne epoxy anticorrosive primer according to claim 1, characterized in that: The waterborne epoxy curing agent includes a waterborne epoxy curing agent 1 and a waterborne epoxy curing agent 2; the active hydrogen equivalent of the waterborne epoxy curing agent 1 is 330 to 370 g / eq, and the active hydrogen equivalent of the waterborne epoxy curing agent 2 is 400 to 450 g / eq; Preferably, the waterborne epoxy curing agent 1 includes Guangzhou Lingwei JT-WBH816, and the waterborne epoxy curing agent 2 includes at least one of Huntsman Aradur 3986 and Guangzhou Lingwei JT-WBH818.

4. The waterborne epoxy anticorrosive primer according to claim 3, characterized in that: When the water-based epoxy curing agent includes Guangzhou Lingwei JT-WBH816 and JT-WBH818, the mass ratio of JT-WBH816 to JT-WBH818 is (0.25-1.25):

1.

5. The waterborne epoxy anticorrosive primer according to claim 1, characterized in that: The additives include at least one of an anti-rust pigment, a film-forming aid, an anti-settling agent, a wetting and dispersing agent, an aqueous defoaming agent, a substrate wetting agent, an adhesion promoter, and a polyurethane thickener; Preferably, the A component includes the following raw materials in parts by mass: 45-60 parts of water-based epoxy resin, 3-12 parts of anti-rust pigment, 10-25 parts of filler, 1-4 parts of film-forming aid, 0.1-0.5 parts of anti-settling agent, 1-2 parts of wetting and dispersing agent, 0.1-0.5 parts of water-based defoaming agent, 0.2-0.7 parts of substrate wetting agent, 0.5-1.0 parts of adhesion promoter, 0.5-1.5 parts of polyurethane thickener, and 8-15 parts of water.

6. The waterborne epoxy anticorrosive primer according to claim 5, characterized in that: The conditions of the auxiliary agent are selected from at least one of the following: a) the anti-rust pigment is selected from phosphate-based anti-rust pigments and / or chromate-based anti-rust pigments; b) the film-forming aid is selected from propylene glycol ether film-forming aids and / or ethylene glycol ether film-forming aids; c) the anti-settling agent is selected from at least one of an organic wax anti-settling agent, an organic modified bentonite anti-settling agent, and a silica anti-settling agent; d) the wetting and dispersing agent is selected from at least one of a polymer block copolymer type solvent-based dispersant, a polymer type water-based dispersant, and a high molecular weight polyester / acrylate type solvent-based dispersant; e) the aqueous defoamer is selected from at least one of a mineral oil-based defoamer, a polyether siloxane-based defoamer, and an acetylenic diol-based defoamer; f) the substrate wetting agent is a polyether-modified polysiloxane wetting agent; g) the adhesion promoter is an epoxy silane oligomer type adhesion promoter; h) The polyurethane thickener is a nonionic polyurethane associative thickener.

7. The waterborne epoxy anticorrosive primer according to claim 1, characterized in that: The cosolvent is an alcohol ether cosolvent; And / or, the anti-flash rust agent is one of an organic zinc chelate anti-flash rust agent and a sodium nitrite anti-flash rust agent, or a combination thereof.

8. The waterborne epoxy anticorrosive primer according to claim 1, characterized in that: In the raw materials for preparing component B, the mass percentage of the anti-flash rust agent is 3%-5%.

9. The method for preparing the waterborne epoxy anticorrosive primer according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: mixing the raw materials for preparing component A to obtain component A, mixing the raw materials for preparing component B to obtain component B, and then mixing component A and component B to obtain a waterborne epoxy anticorrosive primer.

10. Use of the waterborne epoxy anticorrosive primer according to any one of claims 1 to 8 in coating of metal substrates.

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