A kind of acrylic epoxy ester hybrid dispersion and its preparation method and application

Abstract

The present invention relates to an acrylic epoxy ester hybrid dispersion and its preparation method and application, belonging to the technical field of functional coatings. The present invention provides an acrylic epoxy ester hybrid dispersion, comprising the following raw materials: a non-ionic epoxy resin prepolymer, a first mixed monomer, a catalyst, a second mixed monomer, an organic solvent, deionized water and a free radical initiator; the non-ionic epoxy resin prepolymer is formed by the ring-opening reaction of polyetheramine and epoxy resin. The acrylic epoxy ester hybrid dispersion provided by the present invention has excellent oxidative cross-linking ability, and exhibits the characteristics of rapid drying, high gloss, good fullness, high hardness, etc. under room temperature conditions. It is suitable for the preparation of water-based coatings, and can greatly improve the storage stability and hydrolysis resistance of the coating, so that the coating coating has better adhesion, water resistance, chemical corrosion resistance and other properties. The dispersion of the present invention uses water as a medium, has a low organic solvent content, a low VOC content, and has little pollution to the environment.

Description

Technical Field

[0001] The present invention relates to the technical field of functional coatings, and in particular to an acrylic acid epoxy ester hybrid dispersion and a preparation method and application thereof. Background Art

[0002] Alkyd resins, with their advantages of high gloss, excellent body, strong adhesion, and good pigment wettability, are used in a significant portion of traditional coatings. Their raw materials are inexpensive and readily available, and one of their primary raw materials, vegetable oil, is a renewable resource, exempt from petrochemical restrictions. With growing environmental awareness and increasingly stringent environmental regulations, water-based coatings are gradually replacing solvent-based coatings due to their safety and environmental friendliness. The trend toward water-based alkyd resins has become a major industry trend.

[0003] Waterborne alkyd resins have the characteristic of air drying, and during the air drying process, they form a very high molecular weight network through oxidative cross-linking. Generally, waterborne alkyd resins are prepared by adding raw materials containing carboxylic acid groups, and the residual carboxylic acid is neutralized by ammonia or organic amines to achieve the water-based nature of waterborne alkyd resins. It is necessary to add a large amount of water and a hydrophilic organic solvent to disperse it, resulting in a low solid content of the waterborne alkyd resin dispersion, a slow drying speed, low hardness, and poor water resistance; the alkyd resin backbone contains a large number of ester bonds, which usually lead to hydrolysis of the ester bonds due to increased hydrophilicity, resulting in a significant decrease in the storage stability and hydrolysis resistance of the coating. The invention patent with publication number CN115322302A provides a method for preparing an acrylic acid-alkyd hybrid emulsion and its application. By using an acrylic acid-alkyd hybrid resin, the resin properties are improved. By adding an emulsifier, the resin is dispersed by an emulsion polymerization method without pre-treating the hybrid alkyd to make it a dispersion; however, small molecule emulsifiers (such as octylphenol polyoxyethylene ether, etc.) easily migrate to the coating surface, affecting the coating's water resistance and gloss. The invention patent with publication number CN104086712A discloses an epoxy acrylate-modified water-based alkyd resin, its preparation method and application. The alkyd resin is modified by adding epoxy resin and then grafted by adding acrylate. However, due to the low grafting rate of acrylate, organic amine needs to be added to neutralize the acrylate that does not participate in the grafting reaction to obtain a water-based acrylic acid-modified epoxy ester dispersion with excellent performance. During the neutralization reaction, an unpleasant odor will be emitted, causing pollution to the construction site. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies of the prior art and provide an acrylate epoxy ester hybrid dispersion and a preparation method and application thereof.

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

[0006] In a first aspect, the present invention provides an acrylic-epoxy ester hybrid dispersion, comprising the following raw materials in parts by weight: 100-150 parts of a nonionic epoxy resin prepolymer, 310-480 parts of a first mixed monomer, 0.1-1 part of a catalyst, 125-200 parts of a second mixed monomer, 70-90 parts of an organic solvent, 680-800 parts of deionized water, and 10-16 parts of a free radical initiator; the nonionic epoxy resin prepolymer is formed by a ring-opening reaction of a polyetheramine and an epoxy resin; the first mixed monomer comprises the following raw materials in parts by weight: 180-250 parts of unsaturated oleic acid, 65-120 parts of a polyol, 60-90 parts of a polyacid, and 5-20 parts of a polyacid anhydride; the second mixed monomer comprises the following raw materials in parts by weight: 50-150 parts of an acrylate monomer and 50-75 parts of a vinyl monomer.

[0007] The epoxy acrylate hybrid dispersion provided by the present invention has excellent oxidative cross-linking ability and exhibits the characteristics of rapid drying, high gloss, good fullness, and high hardness at room temperature. The epoxy acrylate hybrid dispersion provided by the present invention is suitable for preparing water-based coatings and can greatly improve the storage stability and hydrolysis resistance of the coatings, so that the coating coating has better adhesion, water resistance, chemical corrosion resistance and other properties. The dispersion of the present invention uses water as a medium, has a low solvent content, a low VOC content, has little environmental pollution, and has no fire or safety hazards. The prepared water-based coating can be widely used in rail transportation, automobiles and ships, bridges, steel structures, storage tanks and other fields.

[0008] As a preferred embodiment of the present invention, the acrylic-epoxy hybrid dispersion includes the following raw materials in parts by weight: 120 parts of non-ionic epoxy resin prepolymer, 400 parts of a first mixed monomer, 0.3-0.5 parts of a catalyst, 155-180 parts of a second mixed monomer, 75-80 parts of an organic solvent, 700-750 parts of deionized water, and 12-14 parts of a free radical initiator; the first mixed monomer includes the following raw materials in parts by weight: 200-230 parts of unsaturated oleic acid, 75-100 parts of a polyol, 65-86 parts of a polyacid, and 10-19 parts of a polyacid anhydride; the second mixed monomer includes the following raw materials in parts by weight: 100-110 parts of an acrylate monomer and 55-70 parts of a vinyl monomer. When the raw material components of the epoxy acrylate hybrid dispersion meet this condition, an epoxy acrylate dispersion with moderate particle size and uniform dispersion can be prepared, which can greatly improve the storage stability of the coating, making the coating exhibit the characteristics of fast drying, high gloss, good fullness, high hardness, etc. at room temperature, and also has good water resistance, acid and alkali resistance and salt resistance.

[0009] As a preferred embodiment of the present invention, the nonionic epoxy resin prepolymer is prepared by the following method: after uniformly mixing polyether amine and epoxy resin, heating to 120-150° C., keeping the temperature for reaction for 3-5 hours to obtain the nonionic epoxy resin prepolymer.

[0010] As a preferred embodiment of the present invention, the nonionic epoxy resin prepolymer comprises the following raw materials in parts by weight: 300 to 750 parts of polyether amine and 750 to 1200 parts of epoxy resin.

[0011] Further preferably, the nonionic epoxy resin prepolymer comprises the following raw materials in parts by weight: 480-560 parts of polyether amine and 940-1020 parts of epoxy resin.

[0012] As a preferred embodiment of the present invention, the polyetheramine includes at least one of polyetheramine D-240, polyetheramine D-400, polyetheramine D-2000, polyetheramine M-600, polyetheramine M-1000, polyetheramine M-2070 and polyetheramine M-3085.

[0013] More preferably, the polyetheramine is a mixture of polyetheramine M-2070 and polyetheramine M-1000.

[0014] As a preferred embodiment of the present invention, the epoxy resin includes at least one of epoxy resin E-51, epoxy resin E-44, epoxy resin E-20, epoxy resin E-12 and epoxy resin E-03.

[0015] More preferably, the epoxy resin is epoxy resin E-20 or epoxy resin E-12.

[0016] As a preferred embodiment of the present invention, the free radical initiator includes an oxidant solution and a reducing agent solution, the oxidant in the oxidant solution includes at least one of ammonium persulfate, potassium persulfate and tert-butyl hydroperoxide, and the reducing agent in the reducing agent solution includes at least one of sodium bisulfite, ferrous sulfate, sodium formaldehyde hyposulfite, sodium dithionite, ascorbic acid and isoascorbic acid; in the raw materials of the acrylic epoxy ester hybrid dispersion, the weight portion of the oxidant is 0.5 to 0.8 parts, and the weight portion of the reducing agent is 0.5 to 0.8 parts.

[0017] As a preferred embodiment of the present invention, the unsaturated oleic acid includes at least one of linoleic acid, soybean oleic acid, dehydrated ricinoleic acid, tall oil acid, eleostearic acid and ricinoleic acid.

[0018] More preferably, the unsaturated oleic acid is linoleic acid.

[0019] As a preferred embodiment of the present invention, the polyol includes 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.

[0020] More preferably, the polyol includes any two of neopentyl glycol, ethylene glycol, 1,4-butanediol, trimethylolpropane, pentaerythritol and diethylene glycol.

[0021] More preferably, the polyol is a mixture of pentaerythritol and diethylene glycol, and in the first mixed monomer, the weight portion of pentaerythritol is 61 to 67 parts, and the weight portion of diethylene glycol is 28 to 33 parts.

[0022] As a preferred embodiment of the present invention, the polyacid includes phthalic acid, isophthalic acid, terephthalic acid, fumaric acid, oxalic acid, glutaric acid, adipic acid, sebacic acid, azelaic acid, 1,3-cyclohexanedicarboxylic acid, and 1,4-cyclohexanedicarboxylic acid.

[0023] More preferably, the polyacid is any one of phthalic acid and isophthalic acid.

[0024] As a preferred embodiment of the present invention, the polyacid anhydride includes at least one of maleic anhydride, tetrahydrophthalic anhydride and hexahydrophthalic anhydride.

[0025] More preferably, the polyacid anhydride is tetrahydrophthalic anhydride.

[0026] As a preferred embodiment of the present invention, the acrylate monomer comprises C1-C 18 Acrylate, the C1-C 18 The acrylic acid ester includes at least one of ethyl acrylate, n-butyl acrylate, isobutyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, ethyl methacrylate, and n-butyl methacrylate.

[0027] Further preferably, the acrylate monomer consists of methyl methacrylate and n-butyl methacrylate; in the acrylate monomer, the weight portion of the methyl methacrylate is 67 to 80 parts, and the weight portion of the n-butyl methacrylate is 30 to 33 parts.

[0028] As a preferred embodiment of the present invention, the vinyl monomer includes at least one of styrene and α-methylstyrene.

[0029] More preferably, the vinyl monomer is styrene.

[0030] As a preferred embodiment of the present invention, the catalyst includes at least one of an organic tin catalyst and an organic titanium catalyst; the organic tin catalyst includes at least one of monobutyltin oxide and dibutyltin oxide; the organic titanium catalyst includes at least one of titanium tetraethoxide, titanium tetra-n-propoxide, titanium tetra-n-butoxide, and titanium butyl isopropoxide.

[0031] As a preferred embodiment of the present invention, the organic solvent includes 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.

[0032] More preferably, the organic solvent is ethylene glycol butyl ether.

[0033] As a preferred embodiment of the present invention, the solid content of the epoxy acrylate hybrid dispersion is not less than 41.2%.

[0034] In a second aspect, the present invention provides a method for preparing the epoxy acrylate hybrid dispersion as described in the first aspect, comprising the following steps:

[0035] (1) mixing a nonionic epoxy resin prepolymer, a first mixed monomer, and a catalyst to perform an esterification reaction, and then adding an organic solvent and deionized water to mix and dilute;

[0036] (2) adding the second mixed monomer to the product obtained in step (1) for pre-emulsification and dispersion;

[0037] (3) adding a free radical initiator to the product obtained in step (2) and subjecting the mixture to an in-situ emulsion polymerization reaction to obtain an epoxy acrylate hybrid dispersion.

[0038] Under the action of the catalyst, unsaturated oleic acid, polyacid and polyacid anhydride react with polyol to produce alkyd resin; at the same time, nonionic epoxy resin prepolymer reacts with unsaturated oleic acid to produce nonionic epoxy ester, and the nonionic epoxy ester is introduced into the alkyd molecular chain, with the hydrophilic end of the nonionic epoxy ester "outward" and the hydrophobic end of the alkyd "inward", and after being mixed and diluted with deionized water and an organic solvent, a nonionic epoxy ester modified alkyd resin emulsion is formed; after the second mixed monomer is added, the nonionic epoxy ester modified alkyd resin emulsion can act as an emulsifier, and the second mixed monomer is fully emulsified after pre-emulsification and dispersion; the emulsion After chemistry, under the action of free radical initiator, acrylate monomer and vinyl monomer are polymerized in emulsion to generate acrylic resin, forming polymer microspheres with core-shell structure. The polymer microspheres are evenly distributed to form a dispersion. The polymer microspheres with core-shell structure have non-ionic epoxy ester modified alkyd resin as the shell layer and acrylic resin as the core layer; and the "inward" alkyd hydrophobic end contains double bonds and conjugated double bonds, which undergo free radical polymerization with the acrylate monomer, thereby forming a certain interpenetrating network structure. The core-shell properties complement each other, further improving the stability of the polymer microsphere structure in the dispersion, and improving the storage stability and hydrolysis resistance.

[0039] The present invention achieves water-based properties through nonionic epoxy ester modification. No amine neutralization is required during the preparation process, resulting in low odor and greater environmental friendliness. This allows the acrylic epoxy ester dispersion to be applied to water-based coatings, thereby improving the hydrolysis resistance of the coating. The nonionic epoxy ester's hydrophilic end faces outward, while the alkyd's hydrophobic end faces inward, providing a hydrophobic space for the ester bond and effectively improving the storage stability and hydrolysis resistance of the water-based coating. During the coating film-forming process, the interpenetrating network structure promotes complementary core-shell properties. The nonionic epoxy ester in the shell layer enhances excellent film-forming properties. The introduction of acrylate monomers and vinyl monomers allows the coating to dry quickly, improving the hardness of the coating.

[0040] As a preferred embodiment of the present invention, the step (1) specifically comprises: mixing the first mixed monomer and the nonionic epoxy resin prepolymer, using xylene as a solvent, and performing an esterification reaction under reflux at 200-230° C. until the acid value of the system reaches 3-5 mgKOH / g, then removing the xylene under reduced pressure, cooling to 65-85° C., and adding an organic solvent and deionized water for mixing and dilution.

[0041] As a preferred embodiment of the present invention, the time for pre-emulsification and dispersion in step (2) is 20 to 40 minutes.

[0042] As a preferred embodiment of the present invention, the conditions for the in-situ emulsion polymerization reaction in step (3) are: temperature 45-65° C., time 2-4 h.

[0043] In a third aspect, the present invention provides a use of the epoxy acrylate hybrid dispersion as described in the first aspect in the preparation of a water-based coating.

[0044] In a fourth aspect, the present invention provides a water-based one-component metal anti-corrosion coating comprising the following raw materials: pigments and fillers, cosolvents, additives, deionized water, and the epoxy acrylate hybrid dispersion as described in the first aspect.

[0045] As a preferred embodiment of the present invention, the water-based one-component metal anti-corrosion coating includes the following raw materials in parts by weight: 20 to 35 parts of pigments and fillers, 3 to 5 parts of cosolvents, 1 to 3 parts of additives, 5 to 15 parts of deionized water, and 35 to 65 parts of acrylic epoxy ester hybrid dispersion.

[0046] As a preferred embodiment of the present invention, the cosolvent includes an alcohol ether solvent, and the alcohol ether solvent includes 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.

[0047] As a preferred embodiment of the present invention, the auxiliary agent includes at least one of a pH regulator, a dispersant, a leveling agent, a wetting agent, a defoaming agent, a drying agent, an anti-flash rust agent and a thickener.

[0048] Further preferably, the leveling agent includes at least one of a fluorine-containing surfactant and a polyacrylic acid copolymer.

[0049] Further preferably, the wetting agent includes an organic siloxane copolymer, and the organic siloxane copolymer may be at least one of Tego270 and Tego4100.

[0050] Further preferably, the defoaming agent includes at least one of mineral oil, polyether and silicone defoaming agent; further preferably, it is a silicone defoaming agent, and the silicone defoaming agent can be at least one of silicone defoaming agent Tego810 and silicone defoaming agent Tego902W.

[0051] More preferably, the drying agent comprises at least one of cobalt naphthenate, zirconium naphthenate and zinc naphthenate. For example, the drying agent is water-based drying agent OMG123.

[0052] Further preferably, the thickener includes a nonionic polyurethane thickener, and the nonionic polyurethane thickener may be Hemmings 299.

[0053] As a preferred embodiment of the present invention, the pigments and fillers include at least one of inorganic pigments, organic pigments, metal complex pigments and fillers.

[0054] Further preferably, the inorganic pigment includes at least one of carbon black, graphite, titanium dioxide, red iron oxide, yellow iron oxide, silver powder, aluminum powder, zinc phosphate, aluminum tripolyphosphate, strontium chrome yellow and zinc chrome yellow.

[0055] More preferably, the organic pigments include azo pigments and non-azo pigments; the azo pigments include at least one of monoazo pigments, disazo pigments, condensed azo pigments, and azo condensed pigments; the non-azo pigments include at least one of phthalocyanine blue, phthalocyanine green, thioindigo pigments, anthraquinone pigments, dioxazine pigments, and triarylmethane pigments. The anthraquinone pigment may be at least one of anthrapyrimidine pigments, indanthrone pigments, pyrenanthrone pigments, and dibenzopyrenedione pigments.

[0056] Further preferably, the filler includes at least one of precipitated barium sulfate, light calcium carbonate, heavy calcium carbonate, kaolin, talc, sericite and bentonite.

[0057] As a preferred embodiment of the present invention, the water-based one-component metal anti-corrosion coating further comprises an additional resin, and the additional resin comprises at least one of acrylic resin, polyurethane resin, polyester resin, alkyl resin and epoxy ester resin.

[0058] As a preferred embodiment of the present invention, the additives include a pH regulator, a dispersant, a wetting agent, a defoamer, a drying agent, an anti-flash rust agent and a thickener, and the water-based one-component metal anti-corrosion coating is prepared by the following method:

[0059] S1. Mix deionized water, a pH regulator, a dispersant, a portion of a wetting agent, a portion of a defoaming agent, and a pigment and filler, and grind the mixture to a fineness of less than 20 μm to obtain an aqueous slurry;

[0060] S2. Add the epoxy acrylate hybrid dispersion, cosolvent, drying agent, anti-flash rust agent, thickener, remaining wetting agent and remaining defoaming agent to the aqueous slurry obtained in step S1, stir and mix evenly to obtain a water-based single-component metal anti-corrosion coating.

[0061] Compared with the prior art, the present invention has the following beneficial effects:

[0062] (1) The epoxy acrylate hybrid dispersion provided by the present invention has a nonionic epoxy ester modified alkyd resin as a shell and an acrylic resin as a core, forming a special core-shell structure, having excellent oxidative crosslinking ability, and exhibiting the characteristics of fast drying, high gloss, good fullness, and high hardness at room temperature;

[0063] (2) The epoxy acrylate hybrid dispersion provided by the present invention is suitable for preparing water-based coatings, which can greatly improve the storage stability and hydrolysis resistance of the coatings, so that the coatings have better adhesion, water resistance, chemical corrosion resistance and other properties; with water as the main medium, the organic solvent content is low, the VOC content is low, the environmental pollution is small, and there are no fire and safety hazards. The prepared water-based coatings can be widely used in rail transportation, automobiles and ships, bridges, steel structures, storage tanks and other fields. DETAILED DESCRIPTION

[0064] In order to better illustrate the purpose, technical solutions and advantages of the present invention, the present invention will be further described below in conjunction with specific embodiments.

[0065] Examples 1 to 7

[0066] Examples 1 to 7 provide an epoxy acrylate hybrid dispersion, the preparation method of which is as follows:

[0067] (1) adding polyetheramine and epoxy resin into a 2 L reaction vessel equipped with a stirring mechanism, a condenser, and a heater, and performing a ring-opening reaction at 130° C. for 4 h under stirring to obtain a nonionic epoxy resin prepolymer;

[0068] (2) taking a certain amount of the nonionic epoxy resin prepolymer obtained in step (1), adding the nonionic epoxy resin prepolymer, the first mixed monomer and xylene into a reaction vessel with a capacity of 2 L, wherein the reaction vessel is equipped with a stirring mechanism, a condenser and a heater, and refluxing the xylene at 220° C. under stirring until the acid value of the reaction system reaches 3 to 5 mgKOH / g, extracting the xylene under reduced pressure, cooling to 80° C., and adding ethylene glycol butyl ether and deionized water to mix and dilute;

[0069] (3) adding the second mixed monomer to the product obtained in step (2) and stirring for 30 minutes;

[0070] (4) Adding an aqueous solution of tert-butyl hydroperoxide and an aqueous solution of isoascorbic acid dropwise to the product obtained in step (3) simultaneously, and performing in-situ emulsion polymerization at 60° C. for 3 h to obtain an epoxy acrylate hybrid dispersion.

[0071] The difference between Examples 1 to 7 is that the raw material formula of the nonionic epoxy resin prepolymer used in Examples 1 to 7 is shown in Table 1.

[0072] The amounts of raw materials used in steps (2) to (4) of Examples 1 to 7 are the same, as shown in Example 5 in Table 2.

[0073] Examples 8 to 15

[0074] The preparation methods of epoxy acrylate hybrid dispersions provided in Examples 8 to 15 are different from those in Example 5 in that the raw materials of steps (2) to (4) in Examples 8 to 15 are as shown in Table 2.

[0075] Example 16

[0076] The preparation method of the epoxy acrylate hybrid dispersion provided in this embodiment is:

[0077] (1) adding polyetheramine and epoxy resin into a 2 L reaction vessel equipped with a stirring mechanism, a condenser, and a heater, and performing a ring-opening reaction at 120° C. for 3 h under stirring to obtain a nonionic epoxy resin prepolymer;

[0078] (2) taking a certain amount of the nonionic epoxy resin prepolymer obtained in step (1), adding the nonionic epoxy resin prepolymer, the first mixed monomer and xylene into a reaction vessel with a capacity of 2 L, wherein the reaction vessel is equipped with a stirring mechanism, a condenser and a heater, and refluxing the xylene at 200° C. under stirring until the acid value of the reaction system reaches 3 to 5 mgKOH / g, extracting the xylene under reduced pressure, cooling the mixture to 65° C., and adding ethylene glycol butyl ether and deionized water to mix and dilute the mixture;

[0079] (3) adding the second mixed monomer to the product obtained in step (2) and stirring for 40 minutes;

[0080] (4) Adding an aqueous solution of tert-butyl hydroperoxide and an aqueous solution of isoascorbic acid dropwise to the product obtained in step (3) simultaneously, and performing in-situ emulsion polymerization at 45° C. for 2 h to obtain an epoxy acrylate hybrid dispersion.

[0081] The raw material composition used in step (1) of this embodiment is the same as the raw material composition used in step (1) of Example 5. The raw materials of steps (2) to (4) of this embodiment are shown in Table 2.

[0082] Example 17

[0083] The preparation method of the epoxy acrylate hybrid dispersion provided in this embodiment is:

[0084] (1) adding polyetheramine and epoxy resin into a 2 L reaction vessel equipped with a stirring mechanism, a condenser, and a heater, and performing a ring-opening reaction at 150° C. for 5 h under stirring to obtain a nonionic epoxy resin prepolymer;

[0085] (2) taking a certain amount of the nonionic epoxy resin prepolymer obtained in step (1), adding the nonionic epoxy resin prepolymer, the first mixed monomer and xylene into a reaction vessel with a capacity of 2 L, wherein the reaction vessel is equipped with a stirring mechanism, a condenser and a heater, refluxing the xylene at 230° C. under stirring until the acid value of the reaction system reaches 3 to 5 mgKOH / g, extracting the xylene under reduced pressure, cooling to 85° C., adding ethylene glycol butyl ether and deionized water, and mixing and diluting;

[0086] (3) adding the second mixed monomer to the product obtained in step (2) and stirring for 20 minutes;

[0087] (4) Adding an aqueous solution of tert-butyl hydroperoxide and an aqueous solution of isoascorbic acid dropwise to the product obtained in step (3) simultaneously, and performing in-situ emulsion polymerization at 65° C. for 4 hours to obtain an epoxy acrylate hybrid dispersion.

[0088] The raw material composition used in step (1) of this embodiment is the same as the raw material composition used in step (1) of Example 5. The raw materials of steps (2) to (4) of this embodiment are shown in Table 2.

[0089] Table 1

[0090]

[0091]

[0092] Table 2

[0093]

[0094]

[0095] Comparative Example 1

[0096] This comparative example provides a method for preparing an epoxy acrylate hybrid dispersion, comprising the following steps:

[0097] (1) 120 g of epoxy resin E-20, 200 g of linoleic acid, 65 g of pentaerythritol, 30 g of diethylene glycol, 86 g of isophthalic acid, 19 g of tetrahydrophthalic anhydride, 10 g of xylene, and 0.5 g of monobutyltin oxide were added to a 2 L reaction vessel equipped with a stirring mechanism, a condenser, and a heater. The xylene was refluxed at 220° C. under stirring until the acid value of the reaction system reached 3 to 5 mgKOH / g. The xylene was then removed under reduced pressure, the temperature was lowered to 80° C., and 80 g of ethylene glycol butyl ether was added and the mixture was diluted;

[0098] (2) The second mixed monomer was added dropwise to the product obtained in step (1). During the addition, the temperature in the reaction vessel was maintained at 125° C. After the addition was completed, stirring was continued at 125° C. for 2 h, then cooled to 60° C. and stirred for 30 min. The raw material composition of the second mixed monomer in this comparative example was the same as that of the second mixed monomer in Example 5.

[0099] (3) The product obtained in step (2) was added to 750 g of deionized water, and stirred and dispersed for 30 min to obtain an epoxy acrylate hybrid dispersion.

[0100] Comparative Example 2

[0101] This comparative example provides a method for preparing an acrylic epoxy ester hybrid dispersion, which is different from comparative example 1 in that the epoxy resin used in step (1) of this comparative example is epoxy resin E-12.

[0102] Comparative Example 3

[0103] This comparative example provides a method for preparing an epoxy acrylate hybrid dispersion, comprising the following steps:

[0104] (1) Adding polyetheramine M-2070, epoxy resin E-20, a first mixed monomer, and xylene into a 2 L reaction vessel equipped with a stirring mechanism, a condenser, and a heater, and stirring at 220° C. to reflux xylene and react until the acid value of the reaction system reaches 3 to 5 mgKOH / g. Then, the xylene is removed under reduced pressure, cooled to 80° C., and ethylene glycol butyl ether and deionized water are added to mix and dilute;

[0105] (2) adding the second mixed monomer to the product obtained in step (2) and stirring for 30 minutes;

[0106] (3) Adding an aqueous solution of tert-butyl hydroperoxide and an aqueous solution of isoascorbic acid dropwise to the product obtained in step (2) simultaneously, and performing in-situ emulsion polymerization at 60° C. for 3 h to obtain an epoxy acrylate hybrid dispersion.

[0107] In this comparative example, no nonionic epoxy resin prepolymer was used. The weight of polyetheramine M-2070 was 24 g, the weight of epoxy resin E-20 was 96 g, and the weights of the first mixed monomer, xylene, ethylene glycol butyl ether, deionized water, the second mixed monomer, the aqueous solution of tert-butyl hydroperoxide, and the aqueous solution of isoascorbic acid were the same as the weights of the corresponding raw materials in steps (2) to (4) of Example 5.

[0108] Comparative Example 4

[0109] This comparative example provides a method for preparing an epoxy acrylate hybrid dispersion, comprising the following steps:

[0110] (1) 200 g of polyetheramine M-2070, 360 g of polyetheramine M-1000, and 940 g of epoxy resin E-12 were added to a 2 L reaction vessel equipped with a stirring mechanism, a condenser, and a heater, and a ring-opening reaction was carried out at 130° C. for 4 h under stirring to obtain a nonionic epoxy resin prepolymer;

[0111] (2) 120 g of the nonionic epoxy resin prepolymer obtained in step (1) was taken, and a first mixed monomer consisting of the following raw materials was prepared: 220 g of soybean oleic acid, 67 g of trimethylolpropane, 33 g of neopentyl glycol, 65 g of phthalic acid, 15 g of tetrahydrophthalic anhydride, and 0.5 g of monobutyltin oxide, and 10 g of xylene;

[0112] The nonionic epoxy resin prepolymer, the first mixed monomer and xylene were added to a 2 L reaction vessel equipped with a stirring mechanism, a condenser and a heater. The xylene was refluxed at 220° C. under stirring until the acid value of the reaction system reached 3 to 5 mgKOH / g. The xylene was removed under reduced pressure, the temperature was lowered to 80° C., and 80 g of ethylene glycol butyl ether was added to mix and dilute.

[0113] (3) preparing a second mixed monomer consisting of the following raw materials: 80 g of methyl methacrylate, 30 g of n-butyl methacrylate, 70 g of styrene, and 5 g of tert-butyl peroxy-2-ethylhexyl ester;

[0114] The second mixed monomer and tert-butyl peroxy-2-ethylhexyl ester were added dropwise to the product obtained in step (2). During the addition, the temperature in the reaction vessel was maintained at 125° C. After the addition was completed, stirring was continued at 125° C. for 2 h, and then cooled to 65° C.

[0115] (4) Add 750 g of deionized water to the product obtained in step (3), and stir and disperse for 30 min to obtain an epoxy acrylate hybrid dispersion.

[0116] Effect Example 1

[0117] The products obtained in the above examples and comparative examples were characterized and tested, and the testing method is as follows:

[0118] (1) Place the samples in a transparent glass container and visually observe the appearance of each sample;

[0119] (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;

[0120] (3) Test the viscosity of each sample using a rotational viscometer at 25°C.

[0121] (4) The acid value of the sample was tested by titration, and the OH content relative to 100% solids was further tested;

[0122] (5) using a laser particle size analyzer to measure the average particle size of the polymer in the sample;

[0123] (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;

[0124] (7) Place the sample in a drying oven at 50°C for 30 days and observe the appearance of the sample.

[0125] The test results are shown in Table 3.

[0126] Table 3

[0127]

[0128]

[0129] Compared with Example 5, Comparative Examples 1-2 did not use polyetheramine and did not perform a ring-opening reaction between polyetheramine and epoxy resin. Instead, the epoxy resin, the raw material of the first mixed monomer, xylene and the catalyst were directly mixed, resulting in an excessively high viscosity of the dispersion.

[0130] Compared with Example 5, in Comparative Example 3, the polyetheramine and epoxy resin were not subjected to a ring-opening reaction in advance. Instead, the polyetheramine, epoxy resin, the first mixed monomer and the catalyst were directly mixed, resulting in uneven hydrophilicity distribution and insufficient emulsification of the second mixed monomer, thereby causing the particle size of the polymer particles in the dispersion to be larger and the storage stability to be poor.

[0131] Compared with Example 14, the average particle size of Comparative Example 4 is significantly larger and the storage stability is worse. This may be because the product obtained in step (1) of Comparative Example 4 was not diluted with deionized water, nor was pre-emulsification and dispersion performed. The second mixed monomer and the initiator tert-butyl peroxy 2-ethylhexyl ester were directly added dropwise to the product obtained in step (1). As a result, the grafting rate of the acrylic resin was not high, and a portion of the acrylic ester was not wrapped in the shell layer of the nonionic epoxy ester modified alkyd resin, resulting in a large particle size of the polymer in the dispersion and poor storage stability.

[0132] Application Example 1

[0133] A method for preparing a water-based one-component metal anticorrosion coating comprises the following steps:

[0134] (1) Weigh the following raw materials in parts by weight: 9.4 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), 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 the raw materials until uniform, add them to a sand mill, and grind them to a fineness of <20 μm to obtain an aqueous slurry;

[0135] (2) The following raw materials in parts by weight are added to the color paste in sequence: 55 parts of acrylic epoxy ester hybrid dispersion, 0.8 parts of aqueous drier (OMG123), 5 parts of ethylene glycol butyl ether (BCS), 0.2 parts of wetting agent (Tego4100), 0.1 parts of defoamer (Tego902W), 0.5 parts of anti-flash rust agent (T730) and 0.4 parts of thickener (Hemmings 299), and dispersed evenly to obtain a water-based one-component metal anti-corrosion coating; the acrylic epoxy ester hybrid dispersion is prepared by the preparation method of Example 1.

[0136] Application Examples 2 to 17 and Comparative Application Examples 1 to 4

[0137] Application Examples 2 to 17 and Comparative Examples 1 to 4 respectively provide a method for preparing a water-based one-component metal anticorrosive coating, which differs from Application Example 1 in that:

[0138] The epoxy acrylate hybrid dispersion used in Application Example 2 was prepared by the preparation method of Example 2;

[0139] The epoxy acrylate hybrid dispersion used in Application Example 3 was prepared by the preparation method of Example 3;

[0140] The epoxy acrylate hybrid dispersion used in Application Example 4 was prepared by the preparation method of Example 4;

[0141] The epoxy acrylate hybrid dispersion used in Application Example 5 was prepared by the preparation method of Example 5;

[0142] The epoxy acrylate hybrid dispersion used in Application Example 6 was prepared by the preparation method of Example 6;

[0143] The epoxy acrylate hybrid dispersion used in Application Example 7 was prepared by the preparation method of Example 7;

[0144] The epoxy acrylate hybrid dispersion used in Application Example 8 was prepared by the preparation method of Example 8;

[0145] The epoxy acrylate hybrid dispersion used in Application Example 9 was prepared by the preparation method of Example 9;

[0146] The epoxy acrylate hybrid dispersion used in Application Example 10 was prepared by the preparation method of Example 10;

[0147] The epoxy acrylate hybrid dispersion used in Application Example 11 was prepared by the preparation method of Example 11;

[0148] The epoxy acrylate hybrid dispersion used in Application Example 12 was prepared by the preparation method of Example 12;

[0149] The epoxy acrylate hybrid dispersion used in Application Example 13 was prepared by the preparation method of Example 13;

[0150] The epoxy acrylate hybrid dispersion used in Application Example 14 was prepared by the preparation method of Example 14;

[0151] The epoxy acrylate hybrid dispersion used in Application Example 15 was prepared by the preparation method of Example 15;

[0152] The epoxy acrylate hybrid dispersion used in Application Example 16 was prepared by the preparation method of Example 16;

[0153] The epoxy acrylate hybrid dispersion used in Application Example 17 was prepared by the preparation method of Example 17;

[0154] The epoxy acrylate hybrid dispersion used in Comparative Example 1 was prepared by the preparation method of Comparative Example 1;

[0155] The dispersion used in Comparative Example 2 was prepared by the preparation method of Comparative Example 2;

[0156] The dispersion used in Comparative Example 3 was prepared by the preparation method of Comparative Example 3;

[0157] The dispersion used in Comparative Example 4 was prepared by the preparation method of Comparative Example 4.

[0158] Effect Example 2

[0159] The water-based one-component metal anti-corrosion coatings prepared in each application example and application comparison example were subjected to construction and performance characterization tests.

[0160] 1. The construction method is as follows: Mix the water-based one-component metal anti-corrosion coating with deionized water, spray it on the tinplate, the spray viscosity is 23", the construction temperature is 25℃, the construction humidity is 55%, and the curing time is 7 days at 25℃. The dry film thickness of the coating is 35-45μm.

[0161] 2. The performance characterization test method is as follows:

[0162] (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.

[0163] (2) Non-volatile matter test: According to GB / T1725-2007, 1g of coating sample was taken and dried at 125℃ for 1h. The weight of the dried sample was measured and the non-volatile content in the sample was calculated.

[0164] (3) Surface drying time: The surface drying time is determined in accordance with GB / T 1728-1979. The coating sample is coated on a glass plate with a coating thickness of about 100 μm. A cotton ball is gently placed on the coating surface. The cotton ball is blown lightly in a horizontal direction at a distance of 10 to 15 cm from the mouth. If the cotton ball can be blown away without leaving any cotton fibers on the coating surface, the surface is considered dry and the time is recorded.

[0165] (4) Actual drying time: The coating sample is coated on a glass plate with a coating thickness of about 100 μm. A piece of qualitative filter paper is placed on the coating. 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 (coating 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 coating. The coating is considered to be actually dry and the time is recorded.

[0166] (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.

[0167] (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.

[0168] (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.

[0169] (8) Impact resistance test: The test was carried out in accordance with GB / T 1732-1993 using a BGD 304 coating impactor produced by Guangzhou Biaogeda Co., Ltd.

[0170] (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 coating is observed and the blistering time is recorded.

[0171] (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 coating is observed and the immersion time is recorded.

[0172] (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 coating is observed and the etching time is recorded.

[0173] (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% NaCl solution. The coating was observed and the blistering time was recorded.

[0174] (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 tape. Two damage lines with an angle of 60° were cut in the middle of the sample with a blade. The coating was observed and the corrosion time was recorded.

[0175] (14) Storage stability test: The test was carried out in accordance with GB / T 6753.3-1986. Three samples were taken and 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 odor, etc.

[0176] (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.

[0177] The test results are shown in Table 4.

[0178] Table 4

[0179]

[0180]

[0181]

[0182] From the test results of Application Examples 1 to 7, it can be seen that the proportion of the polyetheramine used in Application Example 1 in the nonionic epoxy resin prepolymer component is too small, resulting in a decrease in the impact resistance of the coating; the proportion of the polyetheramine used in Application Example 4 in the nonionic epoxy resin prepolymer component is too large, resulting in a decrease in the hardness of the coating, and the hardness grade is reduced to HB; the impact resistance or hardness of Application Examples 6 and 7 is worse than that of Application Examples 3 and 5. Therefore, the polyetheramine of the present invention is preferably polyetheramine M-2070, or a mixture of polyetheramine M-2070 and polyetheramine M-1000, and the epoxy resin is preferably epoxy resin E-20 or epoxy resin E-12.

[0183] Among Application Example 5 and Application Examples 8 to 17, the comprehensive performance of the products of Application Examples 8 to 10 and Application Example 15 is better.

[0184] Compared with Application Example 5, Application Comparative Examples 1 to 2 did not use polyetheramine, and did not carry out the ring-opening reaction of polyetheramine and epoxy resin. Instead, the epoxy resin, the raw materials of the first mixed monomer, xylene and the catalyst were directly mixed. This not only resulted in the deterioration of the water resistance, acid and alkali resistance, and salt resistance of the coating, but also reduced the impact resistance of the coating, resulting in excessive viscosity of the dispersion, which in turn resulted in a prolonged surface drying time of the coating.

[0185] Compared with Application Example 5, in Application Comparative Example 3, the polyetheramine and epoxy resin were not subjected to a ring-opening reaction in advance. Instead, the polyetheramine, epoxy resin, the first mixed monomer and the catalyst were directly mixed, resulting in uneven hydrophilicity distribution and insufficient emulsification of the second mixed monomer, thereby causing the particle size of the polymer particles in the dispersion to be larger, the storage stability to be poor, and the water resistance, acid and alkali resistance, and salt resistance of the coating to be poor.

[0186] Compared with Application Example 14, the average particle size of Application Comparative Example 4 is significantly larger, the storage stability is worse, the grafting rate is low and the wrapping is incomplete, resulting in poor water resistance, acid and alkali resistance, salt resistance and other properties of the coating.

[0187] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit the scope of protection of the present invention. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the essence and scope of the technical solutions of the present invention.

Claims

1. An epoxy acrylate hybrid dispersion, characterized in that: The invention comprises the following raw materials in parts by weight: 100-150 parts of nonionic epoxy resin prepolymer, 310-480 parts of a first mixed monomer, 0.1-1 part of a catalyst, 125-200 parts of a second mixed monomer, 70-90 parts of an organic solvent, 680-800 parts of deionized water and 10-16 parts of a free radical initiator; the nonionic epoxy resin prepolymer is formed by a ring-opening reaction of a polyetheramine and an epoxy resin; the first mixed monomer comprises the following raw materials in parts by weight: 180-250 parts of unsaturated oleic acid, 65-120 parts of a polyol, 60-90 parts of a polyacid and 5-20 parts of a polyacid anhydride; the second mixed monomer comprises the following raw materials in parts by weight: 50-150 parts of an acrylate monomer and 50-75 parts of a vinyl monomer; The preparation method of the epoxy acrylate hybrid dispersion comprises the following steps: (1) mixing a nonionic epoxy resin prepolymer, a first mixed monomer, and a catalyst to perform an esterification reaction, and then adding an organic solvent and deionized water to mix and dilute; (2) adding the second mixed monomer to the product obtained in step (1) for pre-emulsification and dispersion; (3) adding a free radical initiator to the product obtained in step (2) and subjecting the mixture to an in-situ emulsion polymerization reaction to obtain an epoxy acrylate hybrid dispersion.

2. The epoxy acrylate hybrid dispersion according to claim 1, wherein The invention comprises the following raw materials in parts by weight: 120 parts of non-ionic epoxy resin prepolymer, 400 parts of a first mixed monomer, 0.3-0.5 parts of a catalyst, 155-180 parts of a second mixed monomer, 75-80 parts of an organic solvent, 700-750 parts of deionized water, and 12-14 parts of a free radical initiator; the non-ionic epoxy resin prepolymer is formed by a ring-opening reaction of a polyetheramine and an epoxy resin; the first mixed monomer comprises the following raw materials in parts by weight: 200-230 parts of unsaturated oleic acid, 75-100 parts of a polyol, 65-86 parts of a polyacid, and 10-19 parts of a polyacid anhydride; the second mixed monomer comprises the following raw materials in parts by weight: 100-110 parts of an acrylate monomer and 55-70 parts of a vinyl monomer.

3. The epoxy acrylate hybrid dispersion according to claim 1, wherein The nonionic epoxy resin prepolymer includes the following raw materials in parts by weight: 300 to 750 parts of polyetheramine and 750 to 1200 parts of epoxy resin; the polyetheramine includes at least one of polyetheramine D-240, polyetheramine D-400, polyetheramine D-2000, polyetheramine M-600, polyetheramine M-1000, polyetheramine M-2070 and polyetheramine M-3085; the epoxy resin includes at least one of epoxy resin E-51, epoxy resin E-44, epoxy resin E-20, epoxy resin E-12 and epoxy resin E-03.

4. A method for preparing an epoxy acrylate hybrid dispersion according to any one of claims 1 to 3, characterized in that: The steps include: (1) mixing a nonionic epoxy resin prepolymer, a first mixed monomer, and a catalyst to perform an esterification reaction, and then adding an organic solvent and deionized water to mix and dilute; (2) adding the second mixed monomer to the product obtained in step (1) for pre-emulsification and dispersion; (3) adding a free radical initiator to the product obtained in step (2) and subjecting the mixture to an in-situ emulsion polymerization reaction to obtain an epoxy acrylate hybrid dispersion.

5. The method for preparing the epoxy acrylate hybrid dispersion according to claim 4, wherein: The step (1) specifically comprises: mixing the nonionic epoxy resin prepolymer and the first mixed monomer, using xylene as a solvent, and conducting a reflux reaction at 200-230° C. until the acid value of the system reaches 3-5 mgKOH / g, then removing the xylene under reduced pressure, cooling to 65-85° C., and then adding an organic solvent and deionized water for mixing and dilution.

6. The method for preparing the epoxy acrylate hybrid dispersion according to claim 5, wherein: The time for pre-emulsification and dispersion in step (2) is 20 to 40 minutes.

7. The method for preparing the epoxy acrylate hybrid dispersion according to claim 5, wherein: The conditions for the in-situ emulsion polymerization reaction in step (3) are: temperature 45-65° C., time 2-4 h.

8. Use of the epoxy acrylate hybrid dispersion according to any one of claims 1 to 3 in the preparation of water-based coatings.

9. A water-based one-component metal anti-corrosion coating, characterized in that: The invention comprises pigments and fillers, cosolvents, additives, deionized water, and the epoxy acrylate hybrid dispersion according to any one of claims 1 to 3.

10. The water-based one-component metal anticorrosion coating according to claim 9, characterized in that: The auxiliary agent includes at least one of a pH regulator, a dispersant, a leveling agent, a wetting agent, a defoamer, a drying agent, an anti-flash rust agent and a thickener; the pigment and filler include at least one of an inorganic pigment, an organic pigment, a metal complex pigment and a filler.

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