阅读说明：本技术 一种环氧树脂改性水性丙烯酸树脂分散体 (Epoxy resin modified waterborne acrylic resin dispersoid ) 是由 金秀华 梁勇 王睿翾 于 2021-09-06 设计创作，主要内容包括：本发明公开了一种环氧树脂改性水性丙烯酸树脂分散体,包括以下原料：环氧酯树脂、丙烯酸树脂,所述丙烯酸树脂包括以下组分：丙烯酸类单体a1、丙烯酸类单体a2、丙烯酸类单体a3、丙烯酸类单体a4和引发剂；所述丙烯酸类单体a1为1-12个碳的醇与丙烯酸或者甲基丙烯酸生成的酯；丙烯酸类单体a2为含有至少一个羟基的丙烯酸或者甲基丙烯酸酯单体；丙烯酸类单体a3为含有不饱和聚氧化烯链化合物；丙烯酸类单体a4为含有可胺中和的酸性官能团单体。本发明是将环氧酯树脂和丙烯酸树脂进行杂化复合在一起,得到综合了两种树脂优点的树脂分散体,克服了两种树脂的缺点,具备较好的硬度,光泽度高,耐老化性和耐盐雾性能优良的特点。(The invention discloses an epoxy resin modified waterborne acrylic resin dispersoid which comprises the following raw materials: epoxy ester resin and acrylic resin, wherein the acrylic resin comprises the following components: acrylic monomer a1, acrylic monomer a2, acrylic monomer a3, acrylic monomer a4 and an initiator; the acrylic monomer a1 is an ester formed by alcohol with 1-12 carbon atoms and acrylic acid or methacrylic acid; the acrylic monomer a2 is an acrylic acid or methacrylic acid ester monomer containing at least one hydroxyl group; the acrylic monomer a3 is a compound containing an unsaturated polyoxyalkylene chain; the acrylic monomer a4 is a monomer containing an acid functional group which can be neutralized with an amine. The invention performs hybridization compounding on the epoxy ester resin and the acrylic resin to obtain the resin dispersoid which integrates the advantages of the two resins, overcomes the defects of the two resins, and has the characteristics of better hardness, high glossiness, aging resistance and excellent salt spray resistance.)

1. The epoxy resin modified waterborne acrylic resin dispersoid is characterized by comprising the following raw materials in parts by weight: 5-50 parts of epoxy ester resin and 50-90 parts of acrylic resin, wherein the acrylic resin comprises the following components: acrylic monomer a1, acrylic monomer a2, acrylic monomer a3, acrylic monomer a4 and an initiator;

the acrylic monomer a1 is an ester formed by alcohol with 1-12 carbon atoms and acrylic acid or methacrylic acid;

the acrylic monomer a2 is an acrylic acid or methacrylic acid ester monomer containing at least one hydroxyl group;

the acrylic monomer a3 is a compound containing an unsaturated polyoxyalkylene chain;

acrylic monomer a4 is an acid functional group containing an amine neutralizable group.

2. The epoxy resin-modified aqueous acrylic resin dispersion according to claim 1, wherein the epoxy ester resin is at least one of E-54, E-51, E-44, E-42, E-31, F-51, F-44, glycerol triglycidyl ether, propoxyglycerol triglycidyl ether, trimethylolpropane triglycidyl ether, castor oil triglycidyl ether, pentaerythritol tetraglycidyl ether, sorbitol glycidyl ether, and a compound or polymer having at least two epoxy groups in a single molecule of the epoxy ester resin.

3. The epoxy-modified aqueous acrylic resin dispersion according to claim 1, wherein the initiator is one or more selected from the group consisting of benzoic peroxide, tert-butyl peroxybenzoate, di-tert-butyl peroxide, di-tert-amyl peroxide, and tert-butyl (amyl) peroxy-2-ethylhexanoate.

4. The epoxy-modified aqueous acrylic resin dispersion according to claim 1, wherein the acrylic monomer a1 is at least one selected from the group consisting of styrene, allyltrimethoxysilane, allyltriethoxysilane, acrylonitrile, methyl (meth) acrylate, butyl (meth) acrylate, isobornyl (meth) acrylate, ethyl (meth) acrylate, cyclohexyl (meth) acrylate, isooctyl (meth) acrylate, and glycidyl methacrylate.

5. The epoxy-modified aqueous acrylic resin dispersion according to claim 1, wherein the acrylic monomer a2 is at least one of hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and hydroxybutyl (meth) acrylate.

6. The epoxy resin modified aqueous acrylic resin dispersion according to claim 1, wherein the acrylic monomer a3 is at least one of (methoxy) polyethylene glycol (meth) acrylate, ethoxy polyethylene glycol (meth) acrylate, propyl (isopropyl) oxy polyethylene glycol (meth) acrylate, butoxy polyethylene glycol (meth) acrylate with a monomer average molecular weight of 200-5000, and the unsaturated terminal in the acrylic monomer a3 may also be one of allyl, epoxy, glycidyl ether, and glycidyl ester.

7. The epoxy-modified aqueous acrylic resin dispersion according to claim 1, wherein the acrylic monomer a4 is at least one of acrylic acid, methacrylic acid, itaconic acid, and sulfostyrene.

8. The epoxy resin modified aqueous acrylic resin dispersion according to claim 1, wherein the dispersion is prepared by any one of the following three methods:

the preparation method comprises the following steps: priming epoxy resin and a solvent, dropwise adding an acrylate monomer step by step, preserving heat, neutralizing, and adding water for dispersing;

the second preparation method comprises the following steps: after acrylic ester monomers are dripped into a solvent to synthesize acrylic resin, epoxy resin is added in the midway, and after high-speed uniform mixing, water is dispersed;

the preparation method comprises the following steps: after the acrylic resin monomer is used for preparing acrylic resin and the synthesis is finished, the epoxy resin is added after the water is added for dispersion.

9. The epoxy resin-modified aqueous acrylic resin dispersion according to claim 9, wherein the solvent is at least one of trimethylbenzene, solvent naphtha, diethylene glycol butyl ether, dipropylene glycol methyl ether, n-butanol, ethylene glycol butyl ether, propylene glycol methyl ether, isopropyl alcohol, and sec-butyl alcohol.

Technical Field

The invention relates to the technical field of water-based paint resin, in particular to an epoxy resin modified water-based acrylic resin dispersoid.

Background

At present, the aqueous acrylic resin dispersion is widely used in various industrial fields including engineering machinery, automobile buses, equipment housings, and the like. The acrylic resin has the performances of high gloss, good fullness, high hardness, excellent weather resistance and the like, and particularly, the hydroxyl acrylate resin with functional groups can be combined with isocyanate curing agents or amino resins to form a water-based two-component polyurethane coating or high-temperature baking paint, so that a paint film has more excellent chemical resistance. However, the waterborne acrylic resin has some self-disadvantages, and the water resistance, chemical resistance and salt spray resistance are greatly reduced due to the introduction of a large amount of hydrophilic groups into a resin chain in the process of waterborne modification. The epoxy ester resin has the advantages of good low-temperature film forming property and good salt spray resistance, and has the defects of poor aging resistance and weather resistance, low drying speed of a paint film and the like, so that a product which can combine the advantages of the acrylic resin and the epoxy resin is obviously welcomed by the market.

At present, some work attempts are made to combine epoxy resin with acrylic resin, but most of them hybridize the epoxy resin by ring-opening and then combining with acrylic resin, and the specific methods include grafting method, esterification method, etherification method, etc. Although the performance is partially improved, the high activity and high salt spray resistance of the epoxy resin are not outstanding, because the epoxy groups can not strongly interact with the base material after ring opening, so that the combination of the paint film and the base material is not tight, and the performance is reduced.

In addition, the methods related to acrylic acid and epoxy hybridization modification almost adopt a method of neutralizing carboxyl to achieve hydrophilicity, but the carboxyl and epoxy are very easy to react in the process, so that resin gelation and performance reduction are easily caused, and potential hazards are caused in storage stability.

Disclosure of Invention

The invention aims to provide an epoxy resin modified waterborne acrylic resin dispersoid to overcome the defects of the two resins, wherein a large number of epoxy groups in the dispersoid can be reserved, a waterborne isocyanate curing agent is added for curing, part of isocyanate groups react with water to generate high-activity amino groups, the epoxy groups can be efficiently opened and the curing agent is crosslinked, and meanwhile, hydroxyl groups on the acrylic resin are crosslinked with the isocyanate curing agent, so that the resin dispersoid which integrates the advantages of the two resins is obtained, and the defects of the two resins are overcome.

In order to achieve the purpose, the invention provides the following technical scheme:

an epoxy resin modified waterborne acrylic resin dispersoid comprises the following raw materials in parts by weight: 5-50 parts of epoxy ester resin, 100 parts of solvent and 50-90 parts of acrylic resin, wherein the acrylic resin comprises the following components: acrylic monomer a1, acrylic monomer a2, acrylic monomer a3, acrylic monomer a4 and an initiator;

the acrylic monomer a1 is an ester formed by alcohol with 1-12 carbon atoms and acrylic acid or methacrylic acid;

the acrylic monomer a2 is an acrylic acid or methacrylic acid ester monomer containing at least one hydroxyl group;

the acrylic monomer a3 is a compound containing an unsaturated polyoxyalkylene chain;

acrylic monomer a4 is an acid functional group containing an amine neutralizable group.

On the basis of the technical scheme, the invention also provides the following optional technical scheme:

in one alternative: the epoxy ester resin is at least one of E-54, E-51, E-44, E-42, E-31, F-51, F-44, glycerol triglycidyl ether, propoxyglycerol triglycidyl ether, trimethylolpropane triglycidyl ether, castor oil triglycidyl ether, pentaerythritol tetraglycidyl ether and sorbitol glycidyl ether, and a compound or polymer of which a single molecule of the epoxy ester resin at least contains two epoxy groups.

In one alternative: the initiator is one or a mixture of more of peroxybenzoic acid, tert-butyl peroxybenzoate, di-tert-butyl peroxide, di-tert-amyl peroxide and tert-butyl peroxy-2-ethylhexanoate (amyl).

In one alternative: the acrylic monomer a1 is at least one of styrene, allyltrimethoxysilane, allyltriethoxysilane, acrylonitrile, methyl (meth) acrylate, butyl (meth) acrylate, isobornyl (meth) acrylate, ethyl (meth) acrylate, cyclohexyl (meth) acrylate, isooctyl (meth) acrylate, and glycidyl methacrylate.

In one alternative: the acrylic monomer a2 is at least one of hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate and hydroxybutyl (meth) acrylate.

In one alternative: the acrylic monomer a3 is at least one of (methoxy) polyethylene glycol (meth) acrylate, ethoxy polyethylene glycol (meth) acrylate, propyl (isopropyl) oxy polyethylene glycol (meth) acrylate and butoxy polyethylene glycol (meth) acrylate with the monomer average molecular weight of 200-5000, wherein the unsaturated end in the acrylic monomer a3 is one of allyl, epoxy, glycidyl ether group and glycidyl ester group.

In one alternative: the acrylic monomer a4 is at least one of acrylic acid, methacrylic acid, itaconic acid, sulfonic styrene and the like.

In one alternative: the preparation of the dispersion adopts any one of the following three preparation methods:

the preparation method comprises the following steps: priming epoxy resin and an organic solvent, dropping an acrylate monomer step by step, preserving heat, neutralizing, and adding water for dispersing;

the second preparation method comprises the following steps: after acrylic ester monomers are dripped into an organic solvent to synthesize acrylic resin, epoxy resin is added in the middle, and after high-speed uniform mixing, water is dispersed;

the preparation method comprises the following steps: after the acrylic resin monomer is used for preparing acrylic resin and the synthesis is finished, the epoxy resin is added after the water is added for dispersion.

In one alternative: the solvent is at least one of trimethylbenzene, solvent naphtha, diethylene glycol butyl ether, dipropylene glycol methyl ether, n-butyl alcohol, ethylene glycol butyl ether, propylene glycol methyl ether, isopropyl alcohol and sec-butyl alcohol.

Compared with the prior art, the invention has the following beneficial effects:

the main body of the invention is an epoxy resin modified aqueous acrylic resin dispersoid, wherein the aqueous dispersoid of the epoxy ester has the advantages of good low-temperature film-forming property and excellent salt mist resistance, and has the defects of poor weather resistance, rich luster and inferior gloss retention compared with acrylic resin; the acrylic resin has good weather resistance and gloss retention because molecules do not contain ether bonds, and meanwhile, various acrylate monomers can adjust the chemical resistance, gloss, toughness and the like of the resin but have poor low-temperature film-forming property and low-temperature impact resistance, and have poor salt spray resistance caused by introduction of hydrophilic groups.

According to the invention, epoxy ester resin and acrylic resin are hybridized and compounded together, a large amount of epoxy groups can be stably reserved, a water-based isocyanate curing agent is added in a curing stage, part of isocyanate groups react with water to generate high-activity amino groups, the epoxy groups can be efficiently opened and the curing agent is crosslinked, and meanwhile, hydroxyl groups on the acrylic resin are crosslinked with the isocyanate curing agent, so that a resin dispersion which integrates the advantages of the two resins is obtained, the defects of the two resins are overcome, and a paint film has the characteristics of good hardness, high glossiness, aging resistance and excellent salt mist resistance.

Detailed Description

The examples are given solely for the purpose of illustration and are not intended to limit the scope of the invention. Any obvious modifications or variations can be made to the present invention without departing from the spirit or scope of the present invention.

An epoxy resin modified waterborne acrylic resin dispersoid comprises the following raw materials in parts by weight: 5-50 parts of epoxy ester resin, 100 parts of solvent and 50-90 parts of acrylic resin, wherein the acrylic resin comprises the following components: acrylic monomer a1, acrylic monomer a2, acrylic monomer a3, acrylic monomer a4 and an initiator;

the acrylic monomer a1 is an ester formed by alcohol with 1-12 carbon atoms and acrylic acid or methacrylic acid;

the acrylic monomer a2 is an acrylic acid or methacrylic acid ester monomer containing at least one hydroxyl group;

the acrylic monomer a3 is a compound containing an unsaturated polyoxyalkylene chain;

acrylic monomer a4 is an acid functional group containing an amine neutralizable group.

On the basis of the technical scheme, the invention also provides the following optional technical scheme:

the epoxy ester resin is at least one of E-54, E-51, E-44, E-42, E-31, F-51, F-44, glycerol triglycidyl ether, propoxyglycerol triglycidyl ether, trimethylolpropane triglycidyl ether, castor oil triglycidyl ether, pentaerythritol tetraglycidyl ether and sorbitol glycidyl ether, and a compound or polymer of which a single molecule of the epoxy ester resin at least contains two epoxy groups.

The initiator is one or a mixture of more of peroxybenzoic acid, tert-butyl peroxybenzoate, di-tert-butyl peroxide, di-tert-amyl peroxide and tert-butyl peroxy-2-ethylhexanoate (amyl).

The solvent is at least one of trimethylbenzene, solvent naphtha, diethylene glycol butyl ether, dipropylene glycol methyl ether, n-butyl alcohol, ethylene glycol butyl ether, propylene glycol methyl ether, isopropyl alcohol and sec-butyl alcohol.

The acrylic monomer a1 is at least one of styrene, allyltrimethoxysilane, allyltriethoxysilane, acrylonitrile, methyl (meth) acrylate, butyl (meth) acrylate, isobornyl (meth) acrylate, ethyl (meth) acrylate, cyclohexyl (meth) acrylate, isooctyl (meth) acrylate, and glycidyl methacrylate.

The acrylic monomer a2 is at least one of hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate and hydroxybutyl (meth) acrylate.

The acrylic monomer a3 is at least one of (methoxy) polyethylene glycol (meth) acrylate, ethoxy polyethylene glycol (meth) acrylate, propyl (isopropyl) oxy polyethylene glycol (meth) acrylate and butoxy polyethylene glycol (meth) acrylate with the monomer average molecular weight of 200-5000, wherein the unsaturated end in the acrylic monomer a3 is one of allyl, epoxy, glycidyl ether group and glycidyl ester group.

The acrylic monomer a4 is at least one of acrylic acid, methacrylic acid, itaconic acid, sulfonic styrene and the like.

The preparation of the dispersion adopts any one of the following three preparation methods:

the preparation method comprises the following steps: priming epoxy resin and an organic solvent, dropping an acrylate monomer step by step, preserving heat, neutralizing, and adding water for dispersing;

the second preparation method comprises the following steps: after acrylic ester monomers are dripped into an organic solvent to synthesize acrylic resin, epoxy resin is added in the middle, and after high-speed uniform mixing, water is dispersed;

the preparation method comprises the following steps: after the acrylic resin monomer is used for preparing acrylic resin and synthesizing the acrylic resin, adding epoxy resin after water is added for dispersion;

generally, method one and method two are preferred.

Example 1

Adding epoxy resin E51100g, 100g of No. 100 solvent oil and 100g of ethylene glycol butyl ether into a reaction bottle, stirring and heating to 148 ℃ at 140 ℃, introducing nitrogen to exhaust air in the bottle, keeping the temperature range, and preparing to dropwise add an acrylic monomer and an initiator;

uniformly mixing 350g of methyl methacrylate, 250g of styrene, 550g of butyl methacrylate and 125g of hydroxyethyl methacrylate, and pouring the mixture into a dropping funnel;

mixing 25g of tert-amyl peroxide, 25g of No. 100 solvent oil and 25g of butyl cellosolve uniformly, and filling the mixture by using another dropping funnel; firstly, adding one fifth of initiator mixed solution into a bottle,

then, simultaneously dripping the monomer and the initiator funnel with the materials for 4-5h, and synchronously finishing dripping;

then 5g of tert-amyl peroxide is added, and the temperature is kept for one hour;

then 125g of methyl methacrylate, 150g of monomethylpolyethyleneglycol methacrylate (Clariant monomethylpolyethyleneglycol methacrylate MA750) with the average molecular weight of 750 and 75g of hydroxyethyl methacrylate are mixed evenly and filled by a dropping funnel;

mixing 9g of tert-amyl peroxide, 25g of No. 100 solvent oil and 25g of butyl cellosolve uniformly, and filling the mixture by using another dropping funnel;

and (3) simultaneously starting dripping by using two dripping funnels, finishing the dripping within 2-3h, then adding 3g of tert-amyl peroxide, preserving the temperature for 2h, and obtaining the epoxy modified acrylic resin after the reaction is finished.

And (3) cooling the modified resin to 90 ℃, slowly adding 2000g of hot water with the temperature of 90 ℃ into the resin, stirring and dispersing at a high speed while adding, naturally cooling, sampling to measure the solid content when the temperature is reduced to about 50 ℃, and adjusting the solid content to about 44% by supplementing water to obtain the epoxy resin modified waterborne acrylic resin dispersoid.

Taking the dispersed epoxy resin modified water-based acrylic resin dispersoid, adding a wetting agent, a defoaming agent, a leveling agent, a pH regulator, a thickening agent, color paste and the like to prepare finished paint;

in addition, the Bayer XP2655 curing agent is diluted to 80 percent by PMA to be used as a curing agent component;

according to the molar ratio of NCO: OH 1.6, spraying the plate on a sand-blasting plate, and baking at 80 ℃ for 30 minutes. The gloss of the obtained paint film is 88 percent, the hardness is HB, and the salt spray resistance is 252 hours.

Example 2

Adding epoxy resin E51120g, No. 100 solvent oil 150g and ethylene glycol monobutyl ether 100g into a reaction bottle, stirring and heating to 130-140 ℃, simultaneously introducing nitrogen to exhaust air in the bottle, keeping the temperature range, and preparing to dropwise add acrylic monomer and initiator;

uniformly mixing 300g of methyl methacrylate, 200g of styrene, 530g of butyl methacrylate, 2g of acrylic acid and 350g of hydroxyethyl methacrylate, and pouring the mixture into a dropping funnel;

mixing 35g of tert-amyl peroxide and 25g of butyl cellosolve uniformly, and filling the mixture by using another dropping funnel; firstly, adding one fifth of initiator mixed solution into a bottle, then simultaneously beginning to dropwise add materials into a monomer and an initiator funnel, synchronously finishing dropwise adding after 4-5h, then supplementing 5g of tert-amyl peroxide, and preserving heat for one hour;

then 50g of methyl methacrylate, 150g of polyethylene glycol monoallyl ether (Kelaien A type polyethylene glycol ether A31/1000) with the molecular weight of 1000 and 150g of hydroxyethyl methacrylate are mixed uniformly and filled by a dropping funnel; 14g of tert-amyl peroxide and 25g of butyl cellosolve are mixed evenly and filled by another dropping funnel; and (3) simultaneously starting dripping by using two dripping funnels, finishing the dripping within 2-3h, then adding 3g of tert-amyl peroxide, preserving the temperature for 2h, and obtaining the epoxy modified acrylic resin after the reaction is finished.

And (3) cooling the modified resin to 80 ℃, slowly adding 2100g of hot water with the temperature of 70 ℃ into the resin, stirring and dispersing at a high speed while adding, naturally cooling, sampling when the temperature is reduced to about 40 ℃, measuring the solid content, and adjusting the solid content to about 44% by supplementing water to obtain the epoxy resin modified waterborne acrylic resin dispersoid.

Taking the dispersed epoxy resin modified water-based acrylic resin dispersoid, adding a wetting agent, a defoaming agent, a leveling agent, a pH regulator, a thickening agent, color paste and the like to prepare finished paint; in addition, the Bayer XP2655 curing agent is diluted to 80 percent by PMA to be used as a curing agent component; according to the molar ratio of NCO: OH 1.6, spraying the plate on a sand-blasting plate, and baking at 80 ℃ for 30 minutes. The gloss of the obtained paint film is 85%, the hardness is F, and the salt spray resistance is 285 hours.

Example 3

Adding 150g of No. 100 solvent oil and 100g of ethylene glycol butyl ether into a reaction bottle, stirring and heating to 140-148 ℃, simultaneously introducing nitrogen to exhaust air in the bottle, keeping the temperature range, and preparing to dropwise add an acrylic monomer and an initiator;

uniformly mixing 450g of methyl methacrylate, 100g of styrene, 375g of butyl acrylate and 350g of hydroxyethyl methacrylate, and pouring the mixture into a dropping funnel;

uniformly mixing 35g of tert-butyl peroxide and 25g of butyl cellosolve, and filling the mixture by using another dropping funnel;

firstly, adding one fifth of initiator mixed solution into a bottle, then simultaneously beginning to dropwise add materials into a monomer and an initiator funnel, synchronously finishing dropwise adding after 4-5h, then supplementing 5g of tert-butyl peroxide, and preserving heat for one hour; then 75g of methyl methacrylate, 150g of polyethylene glycol monomethyl ether glycidyl ether with the molecular weight of 1000, 25g of butyl acrylate, 2g of acrylic acid and 100g of hydroxyethyl methacrylate are uniformly mixed and filled by a dropping funnel;

14g of tert-butyl peroxide and 25g of butyl cellosolve are uniformly mixed and filled by another dropping funnel; and (3) simultaneously starting dripping by using two dripping funnels, finishing the dripping within 2-3h, then adding 3g of tert-butyl peroxide, keeping the temperature for 1h, then adding 120g of epoxy resin E51, keeping the temperature, continuously stirring for 1h, and finally obtaining the epoxy modified acrylic resin after the reaction is finished.

And (2) cooling the modified resin to 80 ℃, slowly adding 2100g of hot water with the temperature of 70 ℃ into the resin, stirring and dispersing at a high speed while adding, adjusting the pH to about 7.5 by using dimethylethanolamine, adding 0.2g of organic tin catalyst, stirring uniformly, naturally cooling, sampling to measure the solid content when the temperature is reduced to about 40 ℃, and adjusting the solid content to about 44% by supplementing water to obtain the epoxy resin modified waterborne acrylic resin dispersoid.

Taking the dispersed epoxy resin modified water-based acrylic resin dispersoid, adding a wetting agent, a defoaming agent, a leveling agent, a pH regulator, a thickening agent, color paste and the like to prepare finished paint;

in addition, the Bayer XP2655 curing agent is diluted to 80 percent by PMA to be used as a curing agent component; according to the molar ratio of NCO: OH 1.6, spraying the plate on a sand-blasting plate, and baking at 80 ℃ for 30 minutes. The gloss of the obtained paint film is 84%, the hardness is H, and the salt spray resistance is 358 hours.

Example 4

Adding 150g of No. 100 solvent oil and 100g of ethylene glycol monobutyl ether into a reaction bottle, stirring and heating to 130-140 ℃, simultaneously introducing nitrogen to exhaust air in the bottle, keeping the temperature range, and preparing to dropwise add an acrylic monomer and an initiator;

uniformly mixing 550g of methyl methacrylate, 175g of styrene, 375g of butyl acrylate, 2g of acrylic acid and 175g of hydroxyethyl methacrylate, and pouring the mixture into a dropping funnel;

mixing 35g of tert-amyl peroxide and 25g of butyl cellosolve uniformly, and filling the mixture by using another dropping funnel;

firstly, adding one fifth of initiator mixed solution into a bottle, then simultaneously beginning to dropwise add materials into a monomer and an initiator funnel, synchronously finishing dropwise adding after 4-5h, then supplementing 5g of tert-amyl peroxide, and preserving heat for one hour; then 125g of methyl methacrylate, 150g of polyethylene glycol monoallyl ether (Kelaien A type polyethylene glycol ether A31/1000) with the molecular weight of 1000, 25g of butyl acrylate and 50g of hydroxyethyl methacrylate are mixed uniformly and filled by a dropping funnel;

14g of tert-amyl peroxide and 25g of butyl cellosolve are mixed evenly and filled by another dropping funnel; and (3) simultaneously starting dripping by using two dripping funnels, finishing the dripping within 2-3h, then adding 3g of tert-amyl peroxide, keeping the temperature for 1h, then adding 120g of epoxy resin E51, keeping the temperature, continuously stirring for 1h, and finally obtaining the epoxy modified acrylic resin after the reaction is finished.

And (3) cooling the modified resin to 80 ℃, slowly adding 2100g of hot water with the temperature of 70 ℃ into the resin, stirring and dispersing at a high speed while adding, naturally cooling, sampling when the temperature is reduced to about 40 ℃, measuring the solid content, and adjusting the solid content to about 44% by supplementing water to obtain the epoxy resin modified waterborne acrylic resin dispersoid.

Taking the dispersed epoxy resin modified water-based acrylic resin dispersoid, adding a wetting agent, a defoaming agent, a leveling agent, a pH regulator, a thickening agent, color paste and the like to prepare finished paint; in addition, the Bayer XP2655 curing agent is diluted to 80 percent by PMA to be used as a curing agent component; according to the molar ratio of NCO: OH 1.6, spraying the plate on a sand-blasting plate, and baking at 80 ℃ for 30 minutes. The gloss of the obtained paint film is 82%, the hardness is HB, and the salt spray resistance is 236 hours.

Example 5

Adding 150g of No. 100 solvent oil and 100g of ethylene glycol butyl ether into a reaction bottle, stirring and heating to 140-148 ℃, simultaneously introducing nitrogen to exhaust air in the bottle, keeping the temperature range, and preparing to dropwise add an acrylic monomer and an initiator;

uniformly mixing 575g of methyl methacrylate, 150g of styrene, 375g of butyl acrylate and 175g of hydroxyethyl methacrylate, and pouring the mixture into a dropping funnel;

uniformly mixing 35g of tert-butyl peroxide and 25g of butyl cellosolve, and filling the mixture by using another dropping funnel;

firstly, adding one fifth of initiator mixed solution into a bottle, then simultaneously beginning to dropwise add materials into a monomer and initiator funnel, completing dropwise addition after 4-5h, then supplementing 5g of tert-butyl peroxide, preserving heat for one hour, adding 120g of epoxy resin E44, preserving heat and continuously stirring for 30 min;

then 125g of methyl methacrylate, 150g of polyethylene glycol monoallyl ether (Kelaien A type polyethylene glycol ether A31/1000) with the molecular weight of 1000, 25g of butyl acrylate and 50g of hydroxyethyl methacrylate are mixed uniformly and filled by a dropping funnel;

14g of tert-butyl peroxide and 25g of butyl cellosolve are uniformly mixed and filled by another dropping funnel; and (3) simultaneously starting to dropwise add the mixture by two dropping funnels, completing the dropwise addition within 2-3h, then adding 3g of tert-butyl peroxide, and finishing the reaction to obtain the epoxy modified acrylic resin.

And (3) cooling the modified resin to 80 ℃, slowly adding 2100g of hot water with the temperature of 70 ℃ into the resin, stirring and dispersing at a high speed while adding, naturally cooling, sampling when the temperature is reduced to about 40 ℃, measuring the solid content, and adjusting the solid content to about 44% by supplementing water to obtain the epoxy resin modified waterborne acrylic resin dispersoid.

Taking the dispersed epoxy resin modified water-based acrylic resin dispersoid, adding a wetting agent, a defoaming agent, a leveling agent, a pH regulator, a thickening agent, color paste and the like to prepare finished paint;

in addition, the Bayer XP2655 curing agent is diluted to 80 percent by PMA to be used as a curing agent component; according to the molar ratio of NCO: OH 1.6, spraying the plate on a sand-blasting plate, and baking at 80 ℃ for 30 minutes. The gloss of the obtained paint film is 86%, the hardness is HB, and the salt spray resistance is 276 hours.

It can be seen that the epoxy resin modified waterborne acrylic resin dispersions obtained in examples 1-5 all have the characteristics of higher glossiness, better hardness and salt spray resistance;

preparing epoxy resin E51 into a water-based epoxy resin emulsion through a commercially available emulsifier, and matching with a commercially available water-based curing agent to carry out a performance test on a spray plate, the epoxy resin modified water-based acrylic resin dispersoid and the commercially available water-based acrylic resin dispersoid of examples 1, 2, 3, 4 and 5 respectively under the same test conditions;

the results are shown in the following table:

it can be seen that the epoxy resin modified aqueous acrylic resin dispersions obtained in examples 1 to 6 have the characteristics of good impact resistance, high gloss of the paint film, good hardness, excellent salt spray resistance and aging resistance, and the like.

The above description is only for the specific embodiments of the present disclosure, but the scope of the present disclosure is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present disclosure, and all the changes or substitutions should be covered within the scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be subject to the protection scope of the claims.