One-component self-drying acrylic dispersion, its preparation method and application

Abstract

The application relates to the field of paint technology and discloses a single-component self-drying acrylic dispersion, a preparation method and application thereof, wherein the single-component self-drying acrylic dispersion comprises deionized water and a copolymer mixture; and the raw materials for preparing the copolymer mixture comprise, in percentage by mass, 33-56% of cashew phenol modified epoxy ester prepolymer, 15-35% of hydrophobic mixed monomers, 10-27% of hydrophilic mixed monomers, 1-10% of an organic solvent, 2-3% of an initiator and 4.5-5.5% of a neutralizing agent. The single-component self-drying acrylic dispersion provided by the application not only has room-temperature oxidation crosslinking capability, but also forms a coating which has the characteristics of fast drying, high gloss, good fullness, high hardness, good wettability for pigments and fillers, good weather resistance, excellent water resistance, salt mist resistance and chemical resistance and the like; can be used for preparing water-based single-component anticorrosive paint, has very low VOC content, causes little environmental pollution and can be widely applied to the fields of rail transit, automobiles and ships, bridges, steel structures and storage tanks.

Description

Technical Field

[0001] The present invention relates to the technical field of coatings, and in particular to a one-component self-drying acrylic acid dispersion and a preparation method and application thereof. Background Art

[0002] Alkyd resin has a considerable proportion in the traditional coatings field due to its advantages such as high gloss, good fullness, good adhesion, and good pigment wettability. The raw materials are cheap and easy to obtain. One of the main raw materials, vegetable oil, is a renewable resource and is not restricted by petrochemicals.

[0003] The raw materials of traditional acrylic resins, epoxy resins or polyurethane resins all come from petrochemicals and are non-renewable resources. With the development of the times and the adjustment and upgrading of industrial energy, reducing or getting rid of dependence on non-renewable resources has become the current development trend in all walks of life.

[0004] Bio-based raw materials, as renewable resources, are gaining increasing attention due to their environmental friendliness, environmental friendliness, affordability, and accessibility in an era of soaring oil prices. Waterborne alkyd resins, made from renewable plant oils and using water as a medium, meet low-carbon requirements while also being environmentally friendly. They are gradually replacing solvent-based coatings and are becoming a major industry trend.

[0005] Currently, the global annual production of cashew nuts is approximately 2 million tons. Cashew nut shells and cardanol are typically treated as waste. Cashew nut shell liquid (CNSL) accounts for approximately 25% of the total weight of cashew nuts. CNSL extracted from discarded cashew nut shells is primarily cardanol. my country, as a major consumer of cardanol, is also the leading importer of CNSL internationally. Cardanol and its derivatives, as natural biophenols, contain a benzene ring structure and 0-3 unsaturated long-chain hydrocarbon groups. Due to their unique structure and renewability, they hold broad application prospects. Currently developed surfactants primarily utilize the phenolic hydroxyl group to introduce hydrophilic groups, while those utilizing unsaturated double bonds in hydrophobic chains are less explored.

[0006] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0007] In view of the above-mentioned deficiencies in the prior art, the object of the present invention is to provide a one-component self-drying acrylic dispersion and its preparation method and application, aiming to solve the problem that the existing oxidative drying resins used as coatings are prone to thixotropy or even gelation with reducing groups, resulting in unstable paint films, low gloss and degraded performance.

[0008] The technical solutions of the present invention are as follows:

[0009] A one-component self-drying acrylic dispersion, comprising deionized water and a copolymer mixture dispersed in the deionized water, wherein the raw materials for preparing the copolymer mixture comprise, by weight percentage, 33-56% of a cardanol-modified epoxy ester prepolymer, 15-35% of a hydrophobic mixed monomer, 10-27% of a hydrophilic mixed monomer, 1-10% of an organic solvent, 2-3% of an initiator, and 4.5-5.5% of a neutralizer; wherein the raw materials for preparing the cardanol-modified epoxy ester prepolymer comprise, by weight percentage, 10-15% of cardanol, 1.5-3.5% of ethyl acetate, 10-20% of ethanol, 10-30% of ethanol, 10-40% of ethanol ... The invention relates to a novel hydrophobic mixed monomer comprising an alcohol amine, 10-20% of a solid epoxy resin, 20-40% of an unsaturated oleic acid, 10-20% of a polyol, 20-30% of a polyacid, and 0-0.5% of a catalyst. The raw materials for preparing the hydrophobic mixed monomer comprise, by weight percentage, 35-62% of a (meth)acrylate monomer, 35-62% of a vinyl monomer, and 1-5% of an initiator. The raw materials for preparing the hydrophilic mixed monomer comprise, by weight percentage, 65-88% of a (meth)acrylate monomer, 10-32% of a carboxyl functional monomer, and 1-5% of an initiator.

[0010] The one-component self-drying acrylic acid dispersion has a mass ratio of deionized water to the copolymer mixture of 1:1.1-1.2.

[0011] The one-component self-drying acrylic dispersion, wherein the neutralizer is at least one of an organic amine and a water-soluble inorganic base; and / or the initiator is at least one of benzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxybenzoate, tert-amyl peroxybenzoate, di-tert-butyl peroxide and di-tert-amyl peroxide.

[0012] The one-component self-drying acrylic dispersion, wherein the catalyst comprises at least one of an organic tin catalyst, titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetra-n-butoxide, butyl titanium isopropoxide, monobutyl tin oxide and dibutyl tin oxide.

[0013] The one-component self-drying acrylic dispersion, wherein the (meth)acrylate monomer is a C1-C18 (meth)acrylate, and the C1-C18 (meth)acrylate is at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate and n-butyl methacrylate; and / or the vinyl monomer is at least one of styrene and α-methylstyrene.

[0014] In the one-component self-drying acrylic acid dispersion, the carboxyl functional monomer is at least one of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid and maleic anhydride.

[0015] The one-component self-drying acrylic dispersion has a solid content greater than 43%.

[0016] A method for preparing the one-component self-drying acrylic acid dispersion according to the present invention comprises the steps of:

[0017] Mixing cardanol with an organic solvent and then adding ethanolamine dropwise to the mixture to carry out a Michael addition reaction to obtain a cardanol intermediate containing a hydroxyl group;

[0018] The cardanol intermediate containing hydroxyl groups is mixed with a solid epoxy resin, unsaturated oleic acid, polyol and polyacid, and simultaneously subjected to ring-opening and esterification reactions to obtain a cardanol-modified epoxy ester prepolymer;

[0019] adding the hydrophobic mixed monomer dropwise into the cardanol-modified epoxy ester prepolymer to carry out a grafting reaction to generate a hydrophobically modified prepolymer;

[0020] Adding the hydrophilic mixed monomer dropwise to the hydrophobically modified prepolymer to carry out a grafting reaction, cooling the prepolymer and then adding a neutralizing agent to generate a copolymer mixture;

[0021] The copolymerization mixture is mixed with deionized water to obtain the one-component self-drying acrylic dispersion.

[0022] An application of the one-component self-drying acrylic acid dispersion according to the present invention, wherein the one-component self-drying acrylic acid dispersion is used to prepare a water-based metal anti-corrosion coating.

[0023] The application, wherein the water-based metal anti-corrosion coating comprises, by weight percentage: 35-65% of a single-component self-drying acrylic dispersion, 5-15% of deionized water, 20-35% of a pigment and filler, 3-5% of a cosolvent, and 1-3% of an additive.

[0024] Beneficial effects: The one-component self-drying acrylic dispersion provided by the present invention not only has room temperature oxidative cross-linking ability, but also combines the advantages of cardanol, epoxy resin, alkyd resin and acrylic resin compared to conventional systems, so that the coating formed thereby exhibits the characteristics of fast drying, high gloss, good fullness, high hardness, good wettability for pigments and fillers, good weather resistance, excellent water resistance, salt spray resistance and chemical resistance; it can be used to prepare water-based one-component anti-corrosion coatings with extremely low VOC content, low environmental pollution, no fire and safety hazards, and can be widely used in rail transportation, automobiles and ships, bridges, steel structures, storage tanks and other fields. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] Figure 1 The present invention provides a flow chart of a method for preparing a one-component self-drying acrylic acid dispersion. DETAILED DESCRIPTION

[0026] The present invention provides a one-component, self-drying acrylic dispersion, a preparation method, and applications thereof. To clarify the objectives, technical solutions, and effects of the present invention, the present invention is described in further detail below. It should be understood that the specific embodiments described herein are intended only to illustrate the present invention and are not intended to limit the present invention.

[0027] In the prior art, acrylic acid-modified alkyd dispersions or acrylic acid-modified epoxy ester dispersions are mostly based on alkyd / epoxy esters, which are obtained by grafting hydrophilic acrylic mixed monomers at one end. However, due to the high content of alkyd / epoxy esters in such resins, they are prone to poor drying properties and hardness. To improve their drying properties and hardness, the conventional approach is to reduce the amount of prepolymer. However, the reduction in the amount of prepolymer is very limited. If it is reduced too much, the reaction viscosity will be too high and the grafting rate will be insufficient, resulting in a large amount of hydrophilic acrylic polymer existing alone in the system. When encountering reducing anti-flash rust agents and anti-rust pigments, it is more likely to cause thixotropic thickening and even glue blooming.

[0028] Based on this, the present invention provides a one-component self-drying acrylic dispersion, which includes deionized water and a copolymer mixture dispersed in the deionized water. The raw materials for preparing the copolymer mixture include, by weight percentage: 33-56% of a cardanol-modified epoxy ester prepolymer, 15-35% of a hydrophobic mixed monomer, 10-27% of a hydrophilic mixed monomer, 1-10% of an organic solvent, 2-3% of an initiator, and 4.5-5.5% of a neutralizer. The raw materials for preparing the cardanol-modified epoxy ester prepolymer include, by weight percentage: 10-15% of cardanol, 1.5-3. 5% of ethanolamine, 10-20% of solid epoxy resin, 20-40% of unsaturated oleic acid, 10-20% of polyol, 20-30% of polyacid, and 0-0.5% of catalyst; the raw materials for preparing the hydrophobic mixed monomer include, by weight percentage, 35-62% of (meth)acrylate monomer, 35-62% of vinyl monomer, and 1-5% of initiator; the raw materials for preparing the hydrophilic mixed monomer include, by weight percentage, 65-88% of (meth)acrylate monomer, 10-32% of carboxyl functional monomer, and 1-5% of initiator.

[0029] The present application utilizes the unsaturated double bond on the long side chain of the bio-based raw material cardanol to introduce a hydroxyl group through "Michael addition reaction" with the amine group on ethanolamine, and then simultaneously performs ring opening and esterification reaction with solid epoxy resin, unsaturated oleic acid, polyol and polyacid, and then performs two-stage acrylic monomer polymerization, and finally obtains the one-component self-drying acrylic dispersion. The present application introduces cardanol, which can effectively reduce the resin viscosity, improve the flexibility, water resistance and salt fog resistance of the coating, and has excellent wettability for pigments and fillers, reduces the use of dispersion wetting agents, and also contains benzene ring structure, improves the hardness, chemical resistance and heat resistance of the coating; the introduction of epoxy resin further improves the adhesion and corrosion resistance of the coating; the present application grafts hydrophobic mixed monomers ("transition layer") first, and then grafts hydrophilic mixed monomers, which greatly improves the compatibility and grafting rate of the cardanol modified epoxy ester prepolymer and the hydrophilic mixed monomers (hydrophilic layer), and obtains a more ideal overall structure, so that the one-component self-drying acrylic dispersion prepared by the present application shows excellent compatibility with anti-flash rust agents and anti-rust pigments when used to prepare water-based anticorrosive coating, and almost does not thixotropy, does not thicken, and does not gel.

[0030] In summary, the one-component self-drying acrylic dispersion provided by the present application not only has room temperature oxidation crosslinking ability, but also combines the advantages of cardanol, epoxy resin, alkyd resin and acrylic resin compared with conventional systems, so that the coating formed by the present application shows the characteristics of fast drying, high gloss, good fullness, high hardness, good wettability for pigments and fillers, good weather resistance, excellent water resistance, salt fog resistance and chemical resistance, etc.; can be used to prepare water-based one-component anticorrosive coating with extremely low VOC content, small environmental pollution, no fire hazard and safety hazard, and can be widely used in fields such as rail transit, automobiles, ships, bridges, steel structures and storage tanks.

[0031] In some embodiments, the cardanol is from at least one of NX-2021, NX-2022, NX-2023, NX-2024, NX-2025 and NX-2026 of the brand of Kardol, and the chemical structural formula is as follows: The -OH group on the cardanol can provide the dispersion with the characteristics of fast low-temperature curing, better adhesion and surfactant effect, the R group can provide the dispersion with the characteristics of water resistance, toughness, low viscosity, surface tension and wettability, and the benzene ring can also provide the dispersion with the characteristics of chemical resistance, heat resistance and fire resistance.

[0032] In some embodiments, the ethanolamine is at least one of ethanolamine, diethanolamine, N-methyl-ethanolamine, N-ethyl-ethanolamine, N-(2-aminoethyl) ethanolamine, but is not limited thereto.

[0033] In some embodiments, during the preparation of the cardanol-modified epoxy ester prepolymer, the molar ratio of cardanol to ethanolamine is 1.1-1.4, but is not limited thereto.

[0034] In some embodiments, the solid epoxy resin is at least one of bisphenol A epoxy resins E-20, E-12, and E-03, but is not limited thereto.

[0035] In some embodiments, the unsaturated oleic acid has an iodine value greater than 130 mg / g and includes at least one of linoleic acid, soybean oleic acid, dehydrated ricinoleic acid, tall oil acid, eleostearic acid, and ricinoleic acid, but is not limited thereto.

[0036] In some embodiments, the polyol refers to an alcohol containing two or more hydroxyl groups in the molecule. For example, the polyol is at least one of neopentyl glycol, ethylene glycol, 1,3-propylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, methyl-1,2-propanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, trimethylolpropane, trimethylolethane, pentaerythritol, dipentaerythritol and glycerol, but is not limited thereto.

[0037] In some embodiments, the polyacid refers to an acid containing two or more carboxyl groups in the molecule, wherein the polyacid is at least one of phthalic acid, isophthalic acid, terephthalic acid, fumaric acid, oxalic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, maleic anhydride, tetrahydrophthalic anhydride and hexahydrophthalic anhydride, but is not limited thereto.

[0038] In some embodiments, the catalyst is at least one of an organotin catalyst, titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetra-n-butoxide, butyl titanium isopropoxide, monobutyl tin oxide, and dibutyl tin oxide, but is not limited thereto.

[0039] In some embodiments, the (meth)acrylate monomer is a C1-C18 (meth)acrylate, and the C1-C18 (meth)acrylate is at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, and n-butyl methacrylate, but is not limited thereto.

[0040] In some embodiments, the vinyl monomer is at least one of styrene and α-methylstyrene, but is not limited thereto.

[0041] In some embodiments, the carboxyl functional monomer is at least one of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid, and maleic anhydride, but is not limited thereto.

[0042] In some embodiments, the initiator is at least one of benzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxybenzoate, tert-amyl peroxybenzoate, di-tert-butyl peroxide and di-tert-amyl peroxide, but is not limited thereto.

[0043] In some embodiments, the organic solvent is at least one of xylene, toluene, ethanol, methanol, ethylene glycol butyl ether, propylene glycol methyl ether, propylene glycol butyl ether, propylene glycol methyl ether acetate, and dipropylene glycol butyl ether, but is not limited thereto.

[0044] In some embodiments, the neutralizing agent is at least one of an organic amine and a water-soluble inorganic base, wherein the organic amine is at least one of dimethylethanolamine, methylethanolamine, triethylamine and triethanolamine, but is not limited thereto.

[0045] In some embodiments, the molar ratio of the neutralizing agent to the carboxyl functional monomer is (1.1-1.2):1. The neutralizing agent is used to neutralize the carboxyl functional monomer, and the neutralizing agent and the carboxyl functional monomer react to form a salt. In this embodiment, a slight excess of neutralizing agent is selected, and the excess neutralizing agent remains in the single-component self-drying acrylic dispersion, thereby significantly improving the dispersion stability and wettability of the coating.

[0046] In some embodiments, the mass ratio of the deionized water to the copolymer mixture is 1:1.1-1.2, wherein the solid content of the one-component self-drying acrylic dispersion is greater than 43%.

[0047] In some embodiments, a method for preparing the one-component self-drying acrylic dispersion according to the present invention is also provided, such as Figure 1 As shown, it includes the steps of:

[0048] S10, mixing cardanol with an organic solvent, and then dropwise adding ethanolamine to the mixture to perform a Michael addition reaction to obtain a cardanol intermediate containing a hydroxyl group;

[0049] S20, mixing the cardanol intermediate containing hydroxyl groups with a solid epoxy resin, unsaturated oleic acid, a polyol, and a polyacid, and simultaneously performing ring-opening and esterification reactions to obtain a cardanol-modified epoxy ester prepolymer;

[0050] S30, adding the hydrophobic mixed monomer dropwise to the cardanol-modified epoxy ester prepolymer for grafting reaction to generate a hydrophobically modified prepolymer;

[0051] S40, dropwise adding the hydrophilic mixed monomer to the hydrophobically modified prepolymer to perform a grafting reaction, cooling the prepolymer and then adding a neutralizing agent to generate a copolymer mixture;

[0052] S50, mixing the copolymer mixture with deionized water to obtain the one-component self-drying acrylic dispersion.

[0053] Specifically, the present invention first adds cardanol and xylene into a reaction vessel and mixes them, heating and stirring to a temperature of 40-60° C., slowly adding ethanolamine dropwise, and reacting for 4-6 hours to obtain a cardanol intermediate containing a hydroxyl group; then the cardanol intermediate containing a hydroxyl group, a solid epoxy resin, an unsaturated oleic acid, a polyol, and a polyacid are mixed and simultaneously subjected to ring-opening and esterification reactions at a temperature of 200-230° C., with xylene reflux, and reacting until the acid value reaches 3-5 mgKOH / g, removing xylene under reduced pressure, cooling to 125-150° C., and then adding an organic solvent to dilute the mixture to obtain a cardanol modified ring. The invention also involves the steps of: adding the hydrophobic mixed monomer dropwise to the cardanol-modified epoxy ester prepolymer for a grafting reaction (transition layer) at a temperature of 125-150°C for 3-4 hours to obtain a hydrophobic modified prepolymer; then adding the hydrophilic mixed monomer dropwise to the hydrophobically modified prepolymer for a grafting reaction at a temperature of 125-150°C for 1-2 hours, maintaining the temperature for 2 hours, cooling, and adding a neutralizing agent to obtain a copolymer mixture; finally, mixing the copolymer mixture with deionized water at a mass ratio of 1.1-1.2:1 to obtain the single-component self-drying acrylic dispersion. The single-component self-drying acrylic dispersion prepared by the present invention has an acid value of 11-15 mgKOH / g and a solids content greater than 43%.

[0054] The present invention utilizes the following reaction principle for preparing a one-component, self-drying acrylic dispersion: The unsaturated double bonds on cardanol react with the amino groups on ethanolamine in a "Michael addition" reaction, introducing hydroxyl groups. This reaction then undergoes simultaneous ring-opening and esterification reactions with epoxy resin, unsaturated oleic acid, polyols, and polyacids to produce a bulky product with a relatively high molecular weight. Finally, a two-stage grafting reaction with acrylic monomers further enhances the hardness, gloss, weather resistance, and chemical resistance of the acrylic resin. By first grafting a hydrophobic mixed monomer ("transition layer") followed by a hydrophilic mixed monomer, the present invention significantly improves the compatibility and grafting efficiency of the cardanol-modified epoxy ester prepolymer and the hydrophilic mixed monomer (hydrophilic layer), resulting in a more ideal overall structure. This single-component, self-drying acrylic dispersion exhibits excellent compatibility with anti-flash rust agents and anti-rust pigments when used in water-based anti-corrosion coating formulations, exhibiting virtually no thixotropy, thickening, or gelling.

[0055] In some embodiments, a use of the one-component, self-drying acrylic dispersion according to the present invention is also provided, wherein the one-component, self-drying acrylic dispersion is used to prepare a waterborne metal anti-corrosion coating. In this embodiment, the waterborne metal anti-corrosion coating comprises, by weight, 35-65% of the one-component, self-drying acrylic dispersion, 5-15% of deionized water, 20-35% of pigments and fillers, 3-5% of a cosolvent, and 1-3% of an additive.

[0056] In this embodiment, the pigment or filler is at least one of an inorganic pigment, an organic pigment, a filler, and an anti-rust pigment, wherein the anti-rust pigment is at least one of zinc phosphate, aluminum tripolyphosphate, strontium chrome yellow, and zinc chrome yellow. The additive is at least one of a wetting agent, a dispersant, a leveling agent, a defoamer, a thickener, a drying agent, a pH adjuster, and an anti-flash rust agent, wherein the anti-flash rust agent is at least one of sodium nitrite, sodium molybdate, strontium chromate, an organic metal chelate, and a multifunctional phosphate chelate.

[0057] It's well known that flash rust inhibitors and anti-rust pigments are essential in water-based industrial coatings primarily for metal substrates. This role is particularly crucial when working with complex substrates and under unusual weather conditions. Therefore, the compatibility and long-term stability of the resin and the flash rust inhibitor in the coating are crucial issues. In oxidatively drying resins like alkyds, acrylics, and epoxy esters, most flash rust inhibitors and anti-rust pigments inhibit corrosion by releasing negative charges through reducing groups. These reducing groups can react with oxidative groups like carboxyl groups in the resin to produce thixotropy or even gelation, leading to increased viscosity, thermal storage instability, reduced gloss, and decreased performance. The present invention greatly improves the compatibility and grafting rate of the cardanol-modified epoxy ester prepolymer and the hydrophilic mixed monomer (hydrophilic layer) by first grafting a hydrophobic mixed monomer ("transition layer") and then grafting a hydrophilic mixed monomer, thereby obtaining a more ideal overall structure. When the single-component self-drying acrylic dispersion is used to prepare a water-based anti-corrosion coating formula, it exhibits excellent compatibility with anti-flash rust agents and anti-rust pigments, and is almost non-thixotropic, non-thickening, and non-gelling.

[0058] In some embodiments, the wetting agent is at least one of polyether-modified silicone and polyether-modified acetylenic alcohol; the leveling agent is at least one of polyether-modified silicone, fluorinated surfactant and polyacrylic acid copolymer; the defoaming agent is at least one of mineral oil, polyether and polyether-modified silicone; the drying agent is at least one of cobalt naphthenate, zirconium naphthenate and zinc naphthenate; the thickener includes a nonionic polyurethane thickener; the pH adjuster is at least one of N,N-dimethylethanolamine, methylethanolamine, triethylamine, 2-amino-2-methyl-1-propanol (AMP-95) and triethanolamine; or the pH adjuster is hydrogen At least one of inorganic bases such as sodium oxide, potassium hydroxide, and ammonia water; the inorganic pigment is at least one of carbon black, graphite, titanium dioxide, red iron oxide, yellow iron oxide, silver powder, and aluminum powder; the organic pigment is at least one of azo pigments, oxazine, dioxazine, thiazine pigments, phenylmethane, triarylmethane, xanthene, diketopyrrolopyrrole, phthalocyanine, ultramarine and other metal complex pigments, indigo pigments, methine pigments, anthraquinone, pyranthrone dyes, diacridine, quinacridone, dinaphthalene and other polycyclic carbonyl pigments; the filler includes at least one of precipitated barium sulfate, light calcium carbonate, heavy calcium carbonate, kaolin, talc and sericite.

[0059] In some embodiments, the water-based metal anti-corrosion coating is added with a pH regulator to ensure that its pH value is 7.5-9.0, and the pH regulator is preferably N,N-dimethylethanolamine. Through research, this embodiment found that N,N-dimethylethanolamine was added as a pH regulator during the preparation of the coating. N,N-dimethylethanolamine contains two polar groups, amino and hydroxyl groups, which can be adsorbed on the surface of the substrate and can form a chelate with iron atoms or iron ions to form a protective film on the surface of the substrate. On the other hand, the amino group can increase the pH value of the coating to help passivate the metal substrate. When the pH value is greater than 7.5, it can have a certain degree of anti-flash rust effect.

[0060] In some embodiments, the co-solvent is an alcohol ether solvent, and the alcohol ether solvent is at least one of ethanol, n-butanol, isobutanol, isopropanol, ethylene glycol butyl ether, propylene glycol methyl ether, diethylene glycol butyl ether and dipropylene glycol butyl ether.

[0061] In some embodiments, the preparation method of the water-based one-component metal anti-corrosion coating comprises the following steps: (1) mixing deionized water, a pH regulator, a dispersant, a wetting agent, a defoaming agent and a pigment and filler uniformly, and grinding the mixture with a sand mill to a fineness of less than 20 μm to obtain a water-based color paste; (2) adding the one-component self-drying acrylic dispersion, a cosolvent, a drying agent, and an anti-flash rust thickener described in the present invention to the water-based color paste, stirring the mixture uniformly to obtain a water-based one-component metal anti-corrosion coating.

[0062] The water-based one-component metal anti-corrosion coating prepared by the present invention can be applied to a substrate to form a surface coating. The application method includes air spraying, airless spraying, electrostatic spraying, brushing, roller coating, or knife coating. The substrate includes metal, glass, or ceramic. The water-based one-component metal anti-corrosion coating of the present invention is more suitable for application to the surface of a metal substrate as a metal topcoat or a primer-and-topcoat.

[0063] The present invention will be further explained below by means of specific embodiments:

[0064] Example 1

[0065] This embodiment provides a one-component self-drying acrylic acid dispersion, the preparation method of which comprises the following steps:

[0066] 1) Add 453 g of cardanol from Cardolite NX-2021 and 100 g of xylene into a reaction vessel equipped with a stirring mechanism, a condenser, and a heater. After heating to 50° C., add 117 g of desdiethanolamine dropwise. React for 4 hours and keep warm for 2 hours to obtain hydroxyl cardanol intermediate 1 with an active ingredient content of 85.1%.

[0067] 2) 129 g of hydroxyl-containing cardanol intermediate 1, 110 g of epoxy resin E-20, 230 g of linoleic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyltin oxide were added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after heating to 200-230 ° C, xylene was refluxed and stirred until the acid value of the reaction system reached 3-5 mgKOH / g, xylene was removed under reduced pressure, cooled to 125 ° C, 110 g of ethylene glycol butyl ether (BCS) was added and diluted to obtain cardanol-modified epoxy ester prepolymer B.

[0068] 3) Add the hydrophobic mixed monomer dropwise to the cardanol color-changing epoxy ester prepolymer B obtained in step 2). During the addition process, the temperature in the reaction container is maintained at 125° C. The addition is continued for 2 hours. After the addition is completed, a hydrophobically modified prepolymer C is obtained.

[0069] 4) Add the hydrophilic mixed monomer dropwise to the hydrophobically modified prepolymer C obtained in step 3), maintaining the temperature in the reaction vessel at 125° C. during the addition, add dropwise for 2 hours, keep warm for 2 hours, cool to below 100° C., add 85.75 g of N,N-dimethylethanolamine, and obtain a hydrophilically modified prepolymer D;

[0070] 5) The hydrophilic modified prepolymer D obtained in step 4) was added to 1700 g of deionized water, and stirred and dispersed for 30 minutes to obtain a single-component self-drying acrylic dispersion.

[0071] In step 3), the hydrophobic mixed monomer consists of the following components: 90 g of methyl methacrylate, 50 g of n-butyl methacrylate, 200 g of styrene and 10 g of tert-butyl peroxy-2-ethylhexyl ester.

[0072] In step 4), the hydrophilic mixed monomer consists of the following components: 250 g of methyl methacrylate, 50 g of n-butyl methacrylate, 60 g of acrylic acid and 10 g of tert-butyl peroxy-2-ethylhexyl ester.

[0073] Example 2

[0074] This example provides a one-component, self-drying acrylic dispersion. The preparation steps and raw materials are the same as those of Example 1, except that a hydroxylated cardanol intermediate 2 is used. The preparation of the hydroxylated cardanol intermediate 2 is as follows: 453 g of cardanol from Cardolite NX-2022 and 90 g of xylene are added to a reaction vessel equipped with a stirring mechanism, a condenser, and a heater. After the reaction vessel is heated to 50°C, 87 g of des-N-methyl-ethanolamine is added dropwise. The reaction is allowed to react for 4 hours and then maintained for 2 hours to obtain the hydroxylated cardanol intermediate 2 with an active ingredient content of 85.7%.

[0075] Example 3

[0076] This example provides a one-component, air-drying acrylic dispersion. Its preparation steps and raw materials are the same as those of Example 1, except that a hydroxylated cardanol intermediate 3 is used. Hydroxylated cardanol intermediate 3 is prepared as follows: 453 g of cardanol from Cardolite NX-2023 and 100 g of xylene are added to a reaction vessel equipped with a stirrer, condenser, and heater. After heating to 50°C, 97 g of N-ethylethanolamine is added dropwise. The reaction is allowed to proceed for 4 hours, followed by a 2-hour incubation period, to obtain hydroxylated cardanol intermediate 3, containing 84.6% active ingredient.

[0077] Example 4

[0078] This example provides a one-component, self-drying acrylic dispersion. The preparation steps and raw materials are the same as those in Example 1, except that a hydroxylated cardanol intermediate 4 is used. The preparation of the hydroxylated cardanol intermediate 4 is as follows: 453 g of cardanol from Cardolite NX-2024 and 90 g of xylene are added to a reaction vessel equipped with a stirring mechanism, a condenser, and a heater. After the reaction vessel is heated to 50°C, 67 g of ethanolamine is added dropwise. The reaction is allowed to react for 4 hours and then maintained for 2 hours to obtain the hydroxylated cardanol intermediate 4 with an active ingredient content of 85.3%.

[0079] Example 5

[0080] This example provides a one-component self-drying acrylic dispersion, the preparation steps and raw materials of which are the same as those of Example 1, except that epoxy resin E-12 is used instead of E-20.

[0081] Example 6

[0082] This example provides a one-component self-drying acrylic dispersion, the preparation steps and raw materials of which are the same as those of Example 1, except that tung oil acid is used instead of linseed oil acid.

[0083] Example 7

[0084] This example provides a one-component self-drying acrylic dispersion (the proportion of hydrophilic and hydrophobic monomers is adjusted while keeping the hydroxyl-containing cardanol intermediate 1 unchanged compared with Example 1), the preparation method of which comprises the following steps:

[0085] 1), 129 g of hydroxyl-containing cardanol intermediate 1, 110 g of epoxy resin E-20, 230 g of linseed oil acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyl tin oxide are added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after being warmed to 200-230°C, xylene is refluxed, and the reaction system is stirred and kept at temperature until the acid value reaches 3-5 mgKOH / g, xylene is removed under reduced pressure, and the temperature is lowered to 125°C, 110 g of ethylene glycol butyl ether (BCS) is added to dilute it, to obtain a cardanol-modified epoxy ester prepolymer B.

[0086] 2), the hydrophobic mixed monomers are added dropwise to the cardanol-modified epoxy ester prepolymer B obtained in step 1), and during the dropping process, the temperature in the reaction vessel is maintained at 125°C, the dropping is carried out for 2 hours, and after the dropping is completed, a hydrophobic modified prepolymer C is obtained.

[0087] 3), the hydrophilic mixed monomers are added dropwise to the hydrophobic modified prepolymer C obtained in step 2), and during the dropping process, the temperature in the reaction vessel is maintained at 125°C, the dropping is carried out for 2 hours, and after the dropping is completed, a hydrophobic modified prepolymer C is obtained.

[0088] 4), the hydrophilic modified prepolymer D obtained in step 3) is added to 1700 g of deionized water, and stirred and dispersed for 30 min to obtain a one-component self-drying acrylic dispersion.

[0089] In step 2), the hydrophobic mixed monomers are composed of the following components: 180 g of methyl methacrylate, 110 g of n-butyl methacrylate, 200 g of styrene and 15 g of tert-butyl 2-ethylhexyl acid peroxide.

[0090] In step 3), the hydrophilic mixed monomer consists of the following components: 120 g of methyl methacrylate, 30 g of n-butyl methacrylate, 60 g of acrylic acid and 6 g of tert-butyl peroxy-2-ethylhexyl ester.

[0091] Example 8

[0092] This embodiment provides a one-component self-drying acrylic acid dispersion (compared with Example 1, the hydroxyl cardanol intermediate 1 is kept unchanged and the overall ratio is adjusted), and the preparation method thereof comprises the following steps:

[0093] 1) 129 g of hydroxyl-containing cardanol intermediate 1, 110 g of epoxy resin E-20, 230 g of linoleic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyltin oxide were added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after heating to 200-230 ° C, xylene was refluxed and stirred until the acid value of the reaction system reached 3-5 mgKOH / g, xylene was removed under reduced pressure, the temperature was lowered to 125 ° C, 110 g of ethylene glycol butyl ether (BCS) was added and diluted to obtain cardanol-modified epoxy ester prepolymer B.

[0094] 2) Add the hydrophobic mixed monomer dropwise to the cardanol color-changing epoxy ester prepolymer B obtained in step 1). During the addition process, the temperature in the reaction container is maintained at 125° C. The addition is continued for 2 hours. After the addition is completed, a hydrophobically modified prepolymer C is obtained.

[0095] 3) Add the hydrophilic mixed monomer dropwise to the hydrophobically modified prepolymer C obtained in step 2), maintaining the temperature in the reaction vessel at 125° C. during the addition process, add dropwise for 2 hours, keep warm for 2 hours, cool to below 100° C., add 100 g of N,N-dimethylethanolamine, and obtain a hydrophilically modified prepolymer D;

[0096] 4) The hydrophilic modified prepolymer D obtained in step 3) was added to 1820 g of deionized water, and stirred and dispersed for 30 minutes to obtain a single-component self-drying acrylic dispersion.

[0097] In step 2), the hydrophobic mixed monomer consists of the following components: 180 g of methyl methacrylate, 110 g of n-butyl methacrylate, 230 g of styrene and 15 g of tert-butyl peroxy-2-ethylhexyl ester.

[0098] In step 3), the hydrophilic mixed monomer consists of the following components: 355 g of methyl methacrylate, 95 g of n-butyl methacrylate, 70 g of acrylic acid and 15 g of tert-butyl peroxy-2-ethylhexyl ester.

[0099] Example 9

[0100] This embodiment provides a one-component self-drying acrylic acid dispersion (compared with Example 1, the hydroxyl cardanol intermediate 1 is kept unchanged and the overall ratio is adjusted), and the preparation method thereof comprises the following steps:

[0101] 1) 129 g of hydroxyl-containing cardanol intermediate, 110 g of epoxy resin E-20, 230 g of linoleic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyltin oxide were added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after heating to 200-230 ° C, xylene was refluxed and stirred until the acid value of the reaction system reached 3-5 mgKOH / g, xylene was removed under reduced pressure, the temperature was lowered to 125 ° C, 110 g of ethylene glycol butyl ether (BCS) was added and diluted to obtain cardanol-modified epoxy ester prepolymer B.

[0102] 2) Add the hydrophobic mixed monomer dropwise to the cardanol color-changing epoxy ester prepolymer B obtained in step 1). During the addition process, the temperature in the reaction container is maintained at 125° C. The addition is continued for 2 hours. After the addition is completed, a hydrophobically modified prepolymer C is obtained.

[0103] 3) Add the hydrophilic mixed monomer dropwise to the hydrophobically modified prepolymer C obtained in step 2), maintaining the temperature in the reaction vessel at 125° C. during the addition, add the mixture dropwise for 2 hours, keep the mixture warm for 2 hours, cool the mixture to below 100° C., and add 71.46 g of N,N-dimethylethanolamine to obtain a hydrophilically modified prepolymer D;

[0104] 4) The hydrophilic modified prepolymer D obtained in step 3) was added to 1450 g of deionized water, and stirred and dispersed for 30 minutes to obtain a single-component self-drying acrylic dispersion.

[0105] In step 2), the hydrophobic mixed monomer consists of the following components: 130 g of methyl methacrylate, 40 g of n-butyl methacrylate, 150 g of styrene and 10 g of tert-butyl peroxy-2-ethylhexyl ester.

[0106] In step 3), the hydrophilic mixed monomer consists of the following components: 100 g of methyl methacrylate, 20 g of n-butyl methacrylate, 50 g of acrylic acid and 5 g of tert-butyl peroxy-2-ethylhexyl ester.

[0107] Comparative Example 1

[0108] This comparative example 1 provides a conventional acrylic acid modified alkyd dispersion, the preparation method of which comprises the following steps:

[0109] (1) 230 g of linoleic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyltin oxide are added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after heating to 200-230° C., xylene is refluxed, and the reaction mixture is stirred at this temperature until the acid value of the reaction system reaches 3-5 mgKOH / g; the xylene is removed under reduced pressure, the temperature is lowered to 125° C., and 130 g of butyl glycol (BCS) is added and diluted to obtain a conventional alkyd prepolymer.

[0110] (2) adding the mixed monomers dropwise to the conventional alkyd prepolymer obtained in step (1), maintaining the temperature in the reaction vessel at 125° C. during the addition; after the addition is completed, stirring is continued at 125° C. for 2 h, then cooled to 60° C., 43 g of N,N-dimethylethanolamine is added to the reaction vessel, and stirring is continued for 30 min to obtain an acrylic acid-modified alkyd prepolymer.

[0111] (3) The acrylic acid modified alkyd prepolymer obtained in step (2) was added to 850 g of deionized water, and stirred and dispersed for 30 minutes to obtain a conventional acrylic acid single-component self-drying acrylic acid dispersion.

[0112] In step (2), the mixed monomer consists of the following components: 70 g of methyl methacrylate, 10 g of n-butyl methacrylate, 130 g of styrene, 30 g of acrylic acid and 8 g of tert-butyl peroxy-2-ethylhexyl ester.

[0113] Comparative Example 2

[0114] This comparative example 2 provides a conventional acrylic acid-modified epoxy ester dispersion, the preparation method of which comprises the following steps:

[0115] (1) 110 g of epoxy resin E-20, 230 g of linoleic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyltin oxide are added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after heating to 200-230° C., xylene is refluxed, and the mixture is stirred at this temperature until the acid value of the reaction system reaches 3-5 mgKOH / g, the xylene is removed under reduced pressure, the temperature is lowered to 125° C., and 140 g of butyl glycol (BCS) is added and diluted to obtain a conventional epoxy ester prepolymer.

[0116] (2) The mixed monomers are added dropwise to the conventional epoxy ester prepolymer obtained in step (1), and the temperature in the reaction vessel is maintained at 125°C during the dropping process; after the dropping is completed, the stirring is continued at 125°C for 2 h, then the temperature is cooled to 60°C, 50 g of N,N-dimethylethanolamine is added into the reaction vessel, and the stirring is continued for 30 min to obtain an acrylic modified epoxy ester prepolymer.

[0117] (3) The acrylic modified epoxy ester prepolymer obtained in step (2) is added into 1020 g of deionized water, and the stirring and dispersion are continued for 30 min to obtain a conventional acrylic one-component self-drying acrylic dispersion.

[0118] In step (2), the mixed monomers are composed of 80 g of methyl methacrylate, 10 g of n-butyl methacrylate, 155 g of styrene, 35 g of acrylic acid, and 8 g of tert-butyl peroxy-2-ethylhexylate.

[0119] Comparative Example 3

[0120] The comparative example 3 provides a cardanol modified alkyd dispersion, and the preparation method thereof comprises the following steps:

[0121] (1) 110 g of cardanol intermediate 1, 230 g of linolenic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid, and 1.0 g of monobutyl tin oxide are added into a reaction vessel which is equipped with a stirring mechanism, a condenser, and a heater; after being warmed to 200-230°C, dimethylbenzene is refluxed, and the temperature is maintained and stirred until the acid value of the reaction system reaches 3-5 mgKOH / g, dimethylbenzene is removed under reduced pressure, and the temperature is lowered to 125°C, and 140 g of ethylene glycol butyl ether (BCS) is added for dilution to obtain a cardanol modified alkyd prepolymer.

[0122] (2) The mixed monomers are added dropwise to the cardanol modified alkyd prepolymer obtained in step (1), and the temperature in the reaction vessel is maintained at 125°C during the dropping process; after the dropping is completed, the stirring is continued at 125°C for 2 h, then the temperature is cooled to 60°C, 50 g of N,N-dimethylethanolamine is added into the reaction vessel, and the stirring is continued for 30 min to obtain an acrylic modified prepolymer.

[0123] (3) The acrylic modified prepolymer obtained in step (2) is added into 1020 g of deionized water, and the stirring and dispersion are continued for 30 min to obtain a conventional acrylic one-component self-drying acrylic dispersion.

[0124] In step (2), the mixed monomers are composed of 80 g of methyl methacrylate, 10 g of n-butyl methacrylate, 155 g of styrene, 35 g of acrylic acid, and 8 g of tert-butyl peroxy-2-ethylhexylate.

[0125] Comparative Example 4

[0126] This comparative example provides a cardanol-modified epoxy ester dispersion, the preparation method of which comprises the following steps:

[0127] (1) 110 g of cardanol intermediate 1, 110 g of epoxy resin E-20, 230 g of linoleic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyltin oxide were added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after heating to 200-230 ° C, xylene was refluxed and stirred until the acid value of the reaction system reached 3-5 mgKOH / g, the xylene was removed under reduced pressure, the temperature was lowered to 125 ° C, and 160 g of ethylene glycol butyl ether (BCS) was added and diluted to obtain a cardanol modified epoxy ester prepolymer.

[0128] (2) adding the mixed monomer dropwise to the cardanol-modified epoxy ester prepolymer obtained in step (1), maintaining the temperature in the reaction vessel at 125° C. during the addition; after the addition is completed, stirring is continued at 125° C. for 2 h, then cooled to 60° C., 57 g of N,N-dimethylethanolamine is added to the reaction vessel, and stirring is continued for 30 min to obtain an acrylic acid-modified prepolymer.

[0129] (3) The acrylic acid modified prepolymer obtained in step (2) was added to 1200 g of deionized water, and stirred and dispersed for 30 minutes to obtain a conventional acrylic acid single-component self-drying acrylic acid dispersion.

[0130] In step (2), the mixed monomer consists of the following components: 90 g of methyl methacrylate, 15 g of n-butyl methacrylate, 180 g of styrene, 40 g of acrylic acid and 10 g of tert-butyl peroxy-2-ethylhexyl ester.

[0131] Comparative Example 5

[0132] This comparative example 5 provides a two-stage acrylic acid modified alkyd dispersion, the preparation method of which comprises the following steps:

[0133] (1) 230 g of linoleic acid, 40 g of trimethylolpropane, 36 g of pentaerythritol, 50 g of diethylene glycol, 60 g of phthalic acid, 40 g of isophthalic acid, 74 g of benzoic acid and 1.0 g of monobutyltin oxide are added to a reaction vessel equipped with a stirring mechanism, a condenser and a heater; after heating to 200-230° C., xylene is refluxed, and the reaction system is stirred at this temperature until the acid value reaches 3-5 mgKOH / g; the xylene is removed under reduced pressure, the temperature is lowered to 125° C., and 120 g of butyl glycol (BCS) is added and diluted to obtain an alkyd prepolymer.

[0134] (2) The hydrophobic mixed monomer is added dropwise to the alkyd prepolymer B obtained in step (1). During the addition, the temperature in the reaction container is maintained at 125° C. The addition is continued for 2 hours. After the addition is completed, a hydrophobically modified prepolymer C is obtained.

[0135] (3) adding the hydrophilic mixed monomer dropwise to the hydrophobically modified prepolymer C obtained in step (2), maintaining the temperature in the reaction vessel at 125° C. during the addition, adding for 2 hours, keeping the temperature for 2 hours, cooling to below 100° C., and adding 43 g of N,N-dimethylethanolamine to obtain a hydrophilically modified prepolymer D;

[0136] (4) The hydrophilic modified prepolymer D obtained in step (3) was added to 850 g of deionized water and stirred for 30 min to obtain an acrylic acid modified alkyd dispersion.

[0137] In step (2), the hydrophobic mixed monomer consists of the following components: 30 g of methyl methacrylate, 10 g of n-butyl methacrylate, 80 g of styrene and 3.6 g of tert-butyl peroxy-2-ethylhexyl ester.

[0138] In step (3), the hydrophilic mixed monomer consists of the following components: 75g methyl methacrylate, 15g n-butyl methacrylate, 30g acrylic acid and 3.6g tert-butyl peroxy-2-ethylhexyl ester.

[0139] Test Example 1

[0140] The products obtained in Examples 1-9 and Comparative Examples 1-5 were subjected to characterization tests, and the test methods are as follows:

[0141] (1) Observe the appearance of each sample by visual inspection;

[0142] (2) Take 1 g of sample, dry it at 125°C for 1 hour, measure the weight of the dried sample, and calculate the non-volatile content of the sample;

[0143] (3) Test the viscosity of each sample using a rotational viscometer at 25°C.

[0144] (4) The acid value of the sample was tested by titration, and the OH content relative to 100% solids was further tested;

[0145] (5) Using a laser particle size analyzer to measure the average particle size of the sample;

[0146] (6) Dilute the sample with deionized water at a mass ratio of 1:4, and then use a pH meter to measure the pH value of the diluted sample;

[0147] (7) Place the sample in a drying oven at 50°C for 30 days and observe the appearance of the sample.

[0148] The test results are shown in Table 1.

[0149] Table 1 Characterization test results

[0150]

[0151]

[0152] Application Example 1

[0153] This application example 1 provides a water-based one-component metal anti-corrosion coating, the preparation method of which includes the following steps:

[0154] 1) Weigh the following raw materials in parts by weight: 10.2 parts of deionized water, 0.2 parts of N,N-dimethylethanolamine (DMEA), 0.5 parts of dispersant (BYK190), 0.1 parts of wetting agent (Tego270), 0.3 parts of defoaming agent (Tego810), 6 parts of titanium dioxide (R996), 0.2 parts of carbon black (MA-100), 20 parts of 1250 mesh precipitated barium sulfate, 5 parts of zinc phosphate and 0.5 parts of bentonite (EW), mix and stir evenly, then add to a sand mill and grind to a fineness of <20 μm to obtain a water-based medium gray slurry;

[0155] 2) The following raw materials in parts by weight are added in sequence to the aqueous medium gray slurry: 50 parts of a one-component self-drying acrylic dispersion, 0.8 parts of an aqueous drier (OMG123), 5 parts of ethylene glycol butyl ether (BCS), 0.2 parts of a substrate wetting agent (Tego4100), 0.1 parts of a defoamer (Tego902W), 0.5 parts of an anti-flash rust agent (T730), and 0.4 parts of a thickener (Hemmings 299), and the mixture is evenly dispersed to obtain a water-based one-component metal anti-corrosion coating; the one-component self-drying acrylic dispersion is prepared by the preparation method of Example 1.

[0156] Application Example 2

[0157] This application example provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of Application Example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of Example 2.

[0158] Application Example 3

[0159] This application example 3 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of example 3.

[0160] Application Example 4

[0161] This application example 4 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of example 4.

[0162] Application Example 5

[0163] This application example 5 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of example 5.

[0164] Application Example 6

[0165] This application example 6 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of example 6.

[0166] Application Example 7

[0167] This application example 7 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of example 7.

[0168] Application Example 8

[0169] This application example 8 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of example 8.

[0170] Application Example 9

[0171] This application example 9 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of example 9.

[0172] Application Example 10

[0173] This application example 10 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of comparative example 1.

[0174] Application Example 11

[0175] This application example 11 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of comparative example 2.

[0176] Application Example 12

[0177] This application example 12 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of comparative example 3.

[0178] Application Example 13

[0179] This application example 13 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of comparative example 4.

[0180] Application Example 14

[0181] This application example 14 provides a water-based one-component metal anti-corrosion coating. The difference between its preparation method and that of application example 1 is that the one-component self-drying acrylic dispersion used in this application example is prepared by the preparation method of comparative example 5.

[0182] Test Example 2

[0183] The water-based one-component metal anti-corrosion coating prepared in Example 1-14 was applied in the following manner:

[0184] Mix the water-based one-component metal anti-corrosion coating with deionized water and spray it on the tinplate. The spray viscosity is 23", the construction temperature is 25℃, the construction humidity is 55%, and the paint is cured at 25℃ for 7 days. The dry film thickness is 35-45μm.

[0185] The paint film obtained by construction is subjected to performance characterization test, and the test method is as follows:

[0186] (1) Viscosity test: The viscosity test was carried out according to GB / T1723-1979 using the Tu-4 cup produced by Guangzhou Biaogeda Co., Ltd.

[0187] (2) Non-volatile matter test: According to GB / T1725-2007, take 1g of paint sample, dry it at 125℃ for 1h, measure the weight of the dried sample, and calculate the non-volatile content in the sample.

[0188] (3) Surface drying time: The surface drying time is determined in accordance with GB / T 1728-1979. The paint sample is coated on a glass plate with a paint film thickness of about 100 μm. A cotton ball is gently placed on the surface of the paint film. The cotton ball is blown lightly in a horizontal direction with the mouth 10-15 cm away from the cotton ball. If it can be blown away without leaving any cotton threads on the surface of the paint film, the surface is considered dry and the time is recorded.

[0189] (4) Actual drying time: The paint sample is coated on a glass plate with a paint film thickness of about 100 μm. A piece of qualitative filter paper is placed on the paint film. A drying tester is then gently placed on the filter paper while the stopwatch is started. After 30 seconds, the drying tester is removed and the sample is turned over (with the paint film facing downward). If the filter paper can fall freely or the back of the sample is tapped several times with the index finger of the hand holding the sample, the filter paper can fall freely without the filter paper fibers sticking to the paint film. The paint film is considered to be actually dry and the time is recorded.

[0190] (5) Gloss test: The gloss test was carried out in accordance with GB / T9754-1998 using a BGD516 / 2 dual-angle gloss meter produced by Guangzhou Biaogeda Co., Ltd.

[0191] (6) Adhesion test: The test was carried out in accordance with GB / T 9286-1998 using the BGD502 tester produced by Guangzhou Biaogeda Co., Ltd.

[0192] (7) Pencil hardness test: The test was carried out in accordance with GB / T 6739-2006 using a BGD 505 combination pencil hardness tester manufactured by Guangzhou Biaogeda Co., Ltd.

[0193] (8) Impact resistance test: The test was carried out in accordance with GB / T 1732-1993 using the BGD 304 paint film impactor produced by Guangzhou Biaogeda Co., Ltd.

[0194] (9) Water resistance test: According to GB / T1733-1993, the sample is sealed with 3M's 600 type tape at room temperature and then immersed in 25°C water. The paint film is observed and the bubbling time is recorded.

[0195] (10) Acid resistance test: According to GB / T9274-1988, the sample is sealed with 3M 600 type tape at room temperature and then immersed in H2SO4 solution with a mass concentration of 0.1 mol / L. The paint film is observed and the bubbling time is recorded.

[0196] (11) Alkali resistance test: According to GB / T9274-1988, the sample is sealed with 3M 600 type tape at room temperature and then immersed in a NaOH solution with a mass concentration of 0.1 mol / L. The paint film is observed and the bubbling time is recorded.

[0197] (12) Salt water resistance test: The test was conducted according to GT / 9274-1988. At room temperature, the sample was sealed with 3M 600 type tape and then immersed in a 5% mass concentration of NaCl solution. The paint film was observed and the blistering time was recorded.

[0198] (13) Salt spray resistance test: The test was carried out in accordance with GB / T1771-2007. At room temperature, the sample was sealed with 3M's 600 type tape. Two damage lines with an angle of 60° were cut in the middle of the sample with a blade. The coating was cut through. The paint film was observed and the corrosion time was recorded.

[0199] (14) Storage stability test: The test was carried out in accordance with GB / T 6753.3-1986. Three samples were placed in a 0.4L standard pressure-capped metal paint can. The sample volume should be about 15mm from the top of the can. After weighing, the samples were placed in a constant temperature drying oven at 50±2℃. After storage for 7 days, the samples were checked for crusting, sedimentation, coarse lumps, viscosity changes, corrosion or corruption smell.

[0200] (15) Artificial aging resistance test: The test was carried out in accordance with GB / T23987-2009 using the QUV / se type ultraviolet accelerated aging tester of the American Q-Panel Company, UVA aging, UVA-340nm lamp, 4 hours of ultraviolet irradiation, and 4 hours of condensation.

[0201] The test results are shown in Table 2.

[0202] Table 2 Paint film performance test results

[0203]

[0204]

[0205] The results in Table 2 above show that compared with Application Examples 10, 11, 12, 13, and 14, Application Examples 1-9 of the present invention add a water-based one-component self-drying acrylic dispersion to the water-based one-component metal anticorrosion paint, and combine the advantages of cardanol, epoxy resin, alkyd resin, and acrylic resin, so that the coating exhibits the characteristics of fast drying, high gloss, good fullness, high hardness, good wettability for pigments and fillers, good weather resistance, excellent water resistance, salt spray resistance, and chemical resistance. In addition, the water-based metal anticorrosion paints of Application Examples 1-9 have excellent storage stability and hydrolysis resistance.

[0206] It should be understood that the application of the present invention is not limited to the above examples. For those skilled in the art, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A one-component self-drying acrylic dispersion, characterized in that: The invention relates to a copolymerization mixture comprising deionized water and a copolymerization mixture dispersed in the deionized water, wherein the raw materials for preparing the copolymerization mixture comprise, by weight percentage, 33-56% of a cardanol-modified epoxy ester prepolymer, 15-35% of a hydrophobic mixed monomer, 10-27% of a hydrophilic mixed monomer, 1-10% of an organic solvent, 2-3% of an initiator, and 4.5-5.5% of a neutralizer; wherein the raw materials for preparing the cardanol-modified epoxy ester prepolymer comprise, by weight percentage, : 10-15% of cardanol, 1.5-3.5% of ethanolamine, 10-20% of solid epoxy resin, 20-40% of unsaturated oleic acid, 10-20% of polyol, 20-30% of polyacid, and 0-0.5% of catalyst; the raw materials for preparing the hydrophobic mixed monomer include, by weight percentage, 35-62% of (meth)acrylate monomer, 35-62% of vinyl monomer, and 1-5% of initiator; preparing the The raw materials of the hydrophilic mixed monomer include, by weight percentage, 65-88% of a (meth)acrylate monomer, 10-32% of a carboxyl functional monomer, and 1-5% of an initiator. The preparation steps of the single-component self-drying acrylic dispersion are as follows: mixing cardanol with an organic solvent, then dropwise adding ethanolamine to the mixture, and performing a Michael addition reaction to obtain a cardanol intermediate containing a hydroxyl group; mixing the cardanol intermediate containing a hydroxyl group with a solid epoxy resin, unsaturated oleic acid, a polyol, and a polyacid, and simultaneously performing ring-opening and esterification reactions to obtain a cardanol-modified epoxy ester prepolymer; dropwise adding the hydrophobic mixed monomer into the cardanol-modified epoxy ester prepolymer, and performing a grafting reaction to generate a hydrophobically modified prepolymer; dropwise adding the hydrophilic mixed monomer into the hydrophobically modified prepolymer, and then performing a grafting reaction, cooling, and then adding a neutralizer to generate a copolymer mixture; and mixing the copolymer mixture with deionized water to obtain the single-component self-drying acrylic dispersion.

2. The one-component self-drying acrylic dispersion according to claim 1, characterized in that The mass ratio of the deionized water to the copolymer mixture is 1:1.1-1.

2.

3. The one-component self-drying acrylic dispersion according to claim 1, characterized in that The neutralizer is at least one of an organic amine and a water-soluble inorganic base; and / or the initiator is at least one of benzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-amyl peroxy-2-ethylhexanoate, tert-butyl peroxybenzoate, tert-amyl peroxybenzoate, di-tert-butyl peroxide and di-tert-amyl peroxide.

4. The one-component self-drying acrylic dispersion according to claim 1, characterized in that The catalyst comprises at least one of an organic tin catalyst, titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetra-n-butoxide, and titanium butyl isopropoxide.

5. The one-component self-drying acrylic dispersion according to claim 1, characterized in that The (meth)acrylate monomer is a C1-C18 (meth)acrylate, and the C1-C18 (meth)acrylate is at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate and n-butyl methacrylate; and / or the vinyl monomer is at least one of styrene and α-methylstyrene.

6. The one-component self-drying acrylic dispersion according to claim 1, characterized in that The carboxyl functional monomer is at least one of acrylic acid, methacrylic acid, itaconic acid, crotonic acid, fumaric acid, maleic acid and maleic anhydride.

7. The one-component self-drying acrylic dispersion according to claim 1, characterized in that The one-component, self-drying acrylic dispersion has a solids content greater than 43%.

8. A method for preparing the one-component self-drying acrylic dispersion according to any one of claims 1 to 7, characterized in that: Including steps: Mixing cardanol with an organic solvent and then adding ethanolamine dropwise to the mixture to carry out a Michael addition reaction to obtain a cardanol intermediate containing a hydroxyl group; The cardanol intermediate containing hydroxyl groups is mixed with a solid epoxy resin, unsaturated oleic acid, polyol and polyacid, and simultaneously subjected to ring-opening and esterification reactions to obtain a cardanol-modified epoxy ester prepolymer; adding the hydrophobic mixed monomer dropwise into the cardanol-modified epoxy ester prepolymer to carry out a grafting reaction to generate a hydrophobically modified prepolymer; Adding the hydrophilic mixed monomer dropwise to the hydrophobically modified prepolymer to carry out a grafting reaction, cooling the prepolymer and then adding a neutralizing agent to generate a copolymer mixture; The copolymerization mixture is mixed with deionized water to obtain the one-component self-drying acrylic dispersion.

9. Use of the one-component self-drying acrylic dispersion according to any one of claims 1 to 7, characterized in that: The one-component self-drying acrylic dispersion is used to prepare a water-based metal anti-corrosion coating.

10. The use according to claim 9, characterized in that The water-based metal anti-corrosion coating comprises, by weight percentage, 35-65% of a single-component self-drying acrylic dispersion, 5-15% of deionized water, 20-35% of pigments and fillers, 3-5% of a cosolvent and 1-3% of an auxiliary agent.

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