KR100577497B1 - Manufacturing method of phase inverted core / shell microgel - Google Patents

Abstract

The present invention relates to a method for preparing a phase inverted core / shell type microgel, and more particularly, to a method for producing a phase inverted core / shell type emulsion resin, wherein the carboxylic acid group is contained in a molecule with respect to 100 parts by weight of the core monomer composition. 10 to 50 parts by weight of the monomer containing, 50 to 90 parts by weight of the non-crosslinkable monomer containing one olefin in the molecule, optionally a crosslinking monomer containing two or more olefins in the molecule and / or an anionic reactive emulsifier Preparing a core emulsion polymer and adding 0.5 to 1.2 equivalents of a neutralizer to 1 equivalent of the carboxylic acid of the prepared core emulsion polymer to prepare a pseudo water-soluble resin; And 88 to 99.9 parts by weight of a non-crosslinkable monomer containing one olefin in a molecule, and 0.1 to 12 parts by weight of a crosslinkable monomer containing two or more olefins in a molecule, based on 100 parts by weight of the shell monomer composition. It relates to a method for preparing a phase inversion core / shell microgel comprising the step of preparing. By using the inverted core / shell-type microgel according to the present invention as the main resin of the paint, a coating composition having excellent water resistance, fouling resistance and plasticity can be obtained.

Description

Manufacturing method of phase inverted core / shell microgel

The present invention relates to a method for preparing a phase-inverted core / shell-type microgel, and more particularly, to preparing a core / shell-type microgel inverted by a two-step emulsion polymerization method so that the microgel emulsion polymer contains a minimum amount of an emulsifier. It is about a method.

In general, emulsion polymers are water-based, so there is no risk of fire and they do not release harmful organic solvents in a large amount, making them easy to handle.However, there are problems to be solved in terms of performance such as transparency, gloss, corrosion resistance, solvent resistance, and mechanical strength of the film. Many organic solvent-type resins are overwhelmingly used until now.

In recent years, the development of emulsion polymers having a variety of functions has been developed along with the improvement of defects of conventional emulsion polymers. One of them is a two-phase structure particle, a multilayer structure particle, and a composite particle emulsion. Called core / shell type emulsions. In other words, the composition of the core and the shell may be differently formed by the multi-stage emulsion polymerization process, thereby reducing costs, improving mechanical properties, and providing good appearance and breathability.

In U.S. Patent No. 4,539,363, a crosslinking agent is added to a core monomer to prepare a crosslinked core, and the core / shell polymer fine particles are synthesized using the same. Described are methods of making gel emulsion polymers and top coat compositions for automobiles containing the same. The composition exhibits excellent spray workability and flow resistance due to the plasticity viscosity behavior and has the advantage of being less affected by the penetration of organic solvents during the subsequent clear coating process due to crosslinking of the particles. It is a composition that the outside of the particles is crosslinked by a crosslinking agent such as melamine-formaldehyde resin at a high temperature of 100 ° C. or higher, and the water resistance is poor in automobile repair paints, plastic paints, and building paints which are dried or baked at a relatively low temperature. Cannot be used. This is because a large amount of low molecular weight emulsifier is used during the polymerization process to synthesize small particles around 100 nm, which provides a water penetration path.

In addition, British Patent No. 2,206,591 discloses an aqueous dispersion of acrylic resins prepared in a solvent and then converted into an aqueous phase through azeotropic distillation to compensate for the poor water resistance of the microgel emulsion polymer added as the main resin of automobile repair paints. Resins and their blending methods are described. However, the method has a variety of problems such as complex polymerization process of the water-dispersible resin to be blended, compatibility between the microgel emulsion polymer and the water-dispersible resin.

On the other hand, Korean Patent No. 149696 describes a core emulsion containing a sufficient amount of carboxylic acid groups prepared by the conventional emulsion polymerization method to reduce the emulsifier content of the conventional core / shell-type emulsion polymer and neutralize it with a neutralizing agent to "like" Water-soluble resin "and a method for stably using it as a polymer dispersant without additionally adding an external low molecular weight emulsifier in preparing a two-stage shell emulsion has been described. Although it has been improved, in addition, there is a problem in that fouling resistance, compactness, plasticity and the like are lowered.

Meanwhile, Lee and Rudin's Polymer Latexes chap. 15, "Control of Core-Shell Latex Morphology", ACS symp. ser. 492, 1992 discusses the various conditions under which core / shells and reversed-phase cores / shells are produced, i.e. core / shell structures can be achieved by constructing the core and shell components hydrophilic and hydrophobic, or polar and nonpolar, respectively. And may advantageously be achieved when the shell component is composed of more fractions than the core component, the core particles are large in size, or the core particles are crosslinked at a high fraction, and the reversed phase core / shell structure is usually in the opposite direction of these conditions. Is formed from.

Therefore, the present inventors have conducted extensive research to solve the conventional problems, and as a result, the phase-inverted core / shell type as a two-stage polymerization process without using an emulsifier in the manufacturing process of the core emulsion polymer of the conventional core / shell two-stage process It has been found that microgels can be prepared and the present invention has been completed based on this.

SUMMARY OF THE INVENTION An object of the present invention is to provide a reversal core / shell type microgel that can be used as a coating material for construction, automobile repair, and plastics, while having the advantages of a coating using a conventional microgel emulsion polymer as a main resin and enhancing water resistance. have.

The method for preparing a phase inverted core / shell-type microgel for achieving the object of the present invention comprises a carboxylic acid group in a molecule with respect to 100 parts by weight of the core monomer composition. Core emulsion by reacting 10 to 50 parts by weight of monomer, 50 to 90 parts by weight of non-crosslinkable monomer containing one olefin in the molecule, and optionally a crosslinkable monomer and / or anionic reactive emulsifier containing two or more olefins in the molecule. Preparing a polymer and adding 0.5 to 1.2 equivalents of a neutralizer to 1 equivalent of carboxylic acid of the prepared core emulsion polymer to prepare a pseudo water-soluble resin; And 88 to 99.9 parts by weight of a non-crosslinkable monomer containing one olefin in a molecule, and 0.1 to 12 parts by weight of a crosslinkable monomer containing two or more olefins in a molecule, based on 100 parts by weight of the shell monomer composition. It consists of manufacturing steps.

Hereinafter, the present invention will be described in more detail.

As described above, the present invention is a step of preparing the core fine particles, the polymer is prepared by the conventional emulsion polymerization method, but acts as a polymer particle stabilizer during the subsequent two-step shell polymerization and phase inversion occurs A sufficient amount of an anionic reactive emulsifier is used in the hydrophilic monomer composition to sufficiently include a monomer having a carboxylic acid group to prepare a core emulsion polymer, and a neutralizing agent is added to prepare a "similar water-soluble resin". As a step, the phase inversion occurs by preparing a hydrophobic monomer composition using a crosslinkable monomer in the shell monomer composition. When such resin is used as the main resin of water-based paint, it has the advantages of the paint using the existing microgel emulsion polymer as the main resin, and also improves water resistance, alkali resistance, rust resistance, adhesion, etc. Can be used. In addition, when the paint is manufactured in the form of crosslinking the outside of the particle of the microgel resin crosslinked inside the particle, the inside and the outside of the particle are crosslinked, so that the crosslinking density of the coating film is higher than that of the non-microgel, so that the stain resistance and the denseness of the coating film are improved. By excellent plasticity, the paint which gives a beautiful appearance and high gloss can be obtained.

Emulsion polymerization refers to a process that requires water in a continuous phase with monomers and initiators and sometimes includes emulsifiers, chain transfer agents to control molecular weight and crosslinkers.

The core emulsion polymerization step 1 of the present invention is a step of preparing a hydrophilic core polymer emulsion sufficiently containing a carboxylic acid group. The core polymer is neutralized with a neutralizing agent consisting of a base to contain a monomer containing sufficient carboxylic acid groups to serve as a polymer dispersion stabilizer in the shell emulsion preparation step of the second step of polymerization.

Examples of the monomer containing a carboxylic acid group in the molecule include monomers containing a single carboxylic acid group consisting of acrylic acid, methacrylic acid, vinylbenzene acid and isopentylbenzene acid, and crotonic acid, itaconic acid, maleic acid, fmaric acid and the like. It is preferable to select one or two or more from the group consisting of monomers containing two carboxylic acid groups composed of acid anhydrides, and the monomer containing carboxylic acid groups preferably contains 10 to 50 parts by weight. If the monomer is less than 10 parts by weight, the degree of water solubility during neutralization is low, and thus there is a problem in that it does not play a role as an emulsifier in the subsequent shell process. This has a problem of deterioration. Generally, monomers containing carboxylic acid groups have different fractions present in the particles / particle surfaces / water phases due to differences in solubility in water.

As another monomer, as a non-crosslinkable monomer containing one olefin in a molecule, C1-C18 alkyl acrylic acid, cycloalkyl acrylic acid, alkoxyalkyl acrylic acid or methacrylic acid ester, and C2-C8 hydroxy alkyl acrylic acid or meta Vinyl aromatic compounds consisting of acrylate esters, styrene and derivatives thereof, conjugated dienes of 4 to 9 carbon atoms and acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl chloride, vinyl acetate, vinyl propinate One or more monomers selected from the group consisting of can be used.

Furthermore, if necessary, divinylbenzene, 1,4-divinylbenzene arylacrylate, and arylmethacryl are crosslinked monomers containing two or more olefins in a molecule in order to increase the graft reaction with a shell component which is subsequently polymerized. Rate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate , Butanediol diacrylate, diaryl phthalate, tripropylene glycol dimethacrylate and trimethylolpropane trimethacrylate may be selected and used in combination of one or more, and the amount used should be sufficiently smaller than the non-crosslinking monomer Reverse fights are possible.

In addition, in order to further reduce the content of the low molecular weight emulsifier in the core component and to facilitate polarization, anionic reactive emulsifiers having vinyl groups that can be polymerized by radicals may be added to give polarity to the core particle surface. . The anionic reactive emulsifier acts as an emulsifier as a kind of monomer, and in particular, anion may anionize the particle surface of the polymer. Examples of anionic reactive emulsifiers include sulfonic acids with olefins, such as vinyl sulfonates, aryl sulfonates, metalyl sulfonates, styrene sulfonates, acrylamido-alkyl sulfonates, and propenyl alkylphenoxy polyethyleneoxy sulfonates. It is preferred that one or more are selected from the group consisting of

In addition, conventional emulsifiers are used either alone or mixed with each other or mixed with each other in order to accelerate the polymerization rate and impart stability of the core emulsion, the amount is used 0.2 to 3.0 parts by weight based on 100 parts by weight of the monomer. If the conventional emulsifier is 0.2 parts by weight or less, the reaction stability is lowered due to the lack of emulsifier. If the emulsifier is more than 3.0 parts by weight, new particles are generated during the reaction with the superemulsifier and the water resistance of the final coating film is lowered. Also examples of emulsifiers are potassium lauryl, potassium stearate, potassium oleate, sodium decyl sulfate, sodium dodecyl sulfate and sodium rosinate, linear or branched alkyl or alkylaryl polyethylene glycols or polypropylene glycol ethers and Ether, alkyl phenoxy poly (ethyleneoxy) ethanol or sulfated ammonium salt thereof, which is an adduct of 1 mole nonylphenol and 5-12 mole ethylene oxide.

The reason for neutralizing the core emulsion polymer in the present invention is to increase the number of particles per unit volume and to prepare a "similar water soluble resin" by disintegrating the primary particles forming the core particles. Here, the purpose of increasing the number of particles per unit volume is to reduce the size of the final core / shell emulsion polymer particles, and the reason for the pseudo-water-soluble resin to the core polymer is that the pseudo-water-soluble resin is a polymer dispersant in step 2 of shell polymerization It can be used to prepare a core / shell emulsion polymer containing a minimum amount of emulsifier, as well as to give a plastic composition viscous behavior to the coating composition containing the emulsifier, such as spray workability, flow resistance In order to improve the smoothness and improve the smoothness of the paint, it is possible to obtain a beautiful appearance and high gloss of the paint dry coating film.

In addition, chain transfer agents may be added to control the molecular weight of the core polymer. Good chain transfer agents have a high transfer activity and should not adversely affect the rate of polymerization, in addition to giving an adjustable molecular weight distribution. For this reason, the amount of the chain transfer agent should be determined in consideration of the type and amount of the polymerization initiator. Generally, 0 to 5 parts by weight is used with respect to 100 parts by weight of the core monomer mixture. Examples of the chain transfer agent that may be used include alkyl mercaptans having 2 to 15 carbon atoms, mercapto carboxylic acids having 2 to 8 carbon atoms, esters thereof, carbon tetrachloride, and bromo trichloromethane.

In addition, radical polymerization initiators can be used both water-soluble and oil-soluble initiators in which radicals are formed by thermal dissociation at high temperatures, and initiators in which radicals are produced by redox reactions at low temperatures. It is a water-soluble thermal dissociation radical initiator which can be given, and the use quantity is 0.2-1.5 weight part with respect to 100 weight part of core monomer mixtures. Examples of the water-soluble thermal dissociation initiators include ammonium, potassium, sodium persulfate and cyclohexyl hydroperoxide, cumene hydroperoxide, n-octyl hydroperoxide, t-butyl hydroperoxide and sec-butyl hydroperoxide. , 1-phenyl-2methylpropyl-1-hydroperoxide and the like.

The polymerization method of the core emulsion follows a semi-continuous process in which initial phase water and an emulsifier are added and initial initiator and monomer are injected in the same manner as the conventional emulsion polymerization method, and the reaction temperature is generally 70 to 90 ° C.

The core emulsion sufficiently containing the carboxylic acid group produced by the present invention is neutralized with a neutralizing agent consisting of a base for use as a polymer dispersant in shell emulsion polymerization in two steps. At this time, the core emulsion polymer has a swelling and dissolution behavior competitively, and the factors influencing the competition behavior are the type of neutralizing agent, the appropriate neutralization (pH value), the hydrophilicity of the core composition, core particle structure and the like. In the present invention, it is possible to obtain a two-stage shell emulsion polymerization stability without containing an external low molecular weight emulsifier and to obtain a core-shell emulsion polymer containing a minimum amount of an emulsifier because the neutralized core emulsion serves as a polymer dispersant. Therefore, the morphology of the neutralized core polymer should be controlled.

The neutralizing agents are primary and secondary, such as inorganic bases ammonia, sodium hydroxide (NaOH), potassium hydroxide (KOH), lithium hydroxide (LiOH) and organic bases dimethylethanol amine, AMP 95 (manufactured by Angus) and triethyl amine. And tertiary amines, and the amount thereof is used in an amount of 0.5 to 1.2 equivalents based on 1 equivalent of carboxylic acid in the core. If the neutralizing agent is less than 0.5 equivalent, there is a problem that the degree of solubilization during neutralization does not play a role of the emulsifier in the subsequent shell process, and if the equivalent exceeds 1.2 equivalent, the role of the emulsifier does not function as in the shell process subsequent to complete solubilization. There is a problem. The degree of neutralization is the most important factor in the swelling / dissolution behavior of the core emulsion polymer, and as the degree of neutralization increases, the dissolution behavior becomes stronger, so that the solubility of the core particles is promoted, but the degree of neutralization does not give the stability of the two-stage shell emulsion polymerization. . Therefore, in order to give stability of the two-stage emulsion polymerization, an appropriate degree of neutralization is required, and in the present invention, a neutralization degree of 7 to 75% is appropriate for the total amount of carboxylic acid groups of the core polymer, and the pH is 4.5 to 8.0. to be.

The emulsion polymerization step is a shell emulsion production step of preparing an emulsion by using the neutralized core emulsion polymer as a dispersion stabilizer without adding an external low molecular weight emulsifier or by adding only a small amount as compared to a conventional core / shell emulsion polymerization method. As such, the monomers are selected depending on the Tg of the core / shell polymer and the use of the end use paint. The shell polymerization monomer is 88.0 to 99.9 parts by weight of a non-crosslinkable monomer containing one olefin in a molecule relative to 100 parts by weight of the shell monomer composition among the monomers mentioned in the step of preparing the core emulsion polymer, and two or more olefins in the molecule. 0.1-12 weight part of crosslinking monomers containing these are mixed, and a shell polymer is added, Most preferably, it is a strong hydrophobic monomer of 1, 4- divinylbenzene as a crosslinking monomer.

As the initiator used in the shell polymerization of the second step, as in the core composition, a water-soluble initiator, or in particular, an oil-soluble initiator can be used to make the shell composition nonpolar. Polymerization is also possible in the form of redox initiators. The amount used is 0.1 to 1.5 parts by weight based on 100 parts by weight of the shell polymerization monomer in the two stages. Oil-soluble initiators include dialkyl peroxides such as t-butyl benzoperoxide and 2,2'-azobis (isobutyrotytrile), 2,2'-azobis (methylbutyronitrile), and 1,1'- There are compounds such as azobis (1-cyclohexane carbonitrile), and examples of reducing agents for water-soluble and oil-soluble initiators include alkali metal sulfite, hypo sulfite and sodium formaldehyde sulfoxylate.

The mixing ratio of the core emulsion polymer and the shell emulsion polymer prepared as described above is 1: 0.5 to 1:20, preferably 1: 1 to 1:15.

The two-stage emulsion polymerization method follows a semi-continuous process in which water and a neutralized core emulsion are initially injected, followed by an initiator and a second monomer, but the polymerization temperature is 60 to 90 ° C. In addition, the reaction phase is a water phase alone or a mixed phase of butyl cellosolve, ethyl cellosolve, and texanol (manufactured by Eastman) and water, which are used as coating film forming solvents in coating applications, and the amount of co-solvent is from 0 to 100 parts by weight of the core emulsion polymer. 200 parts by weight is used.

The core / shell emulsions thus prepared are adjusted to pH 8-10 with the above-mentioned neutralizing agents for imparting storage stability and for application in paints.

The total solid content of paint is 20% or more, and the pigment is used so that the pigment volume percentage (PVC) is 15-20 with respect to the total water-soluble coating composition. Other paint additives include crosslinking agents, fillers, plasticizers, rheology modifiers and antioxidants. , A solvent, a dispersant, an antifoaming agent, a leveling agent, and the like, and 0.1 to 12 parts by weight can be used with respect to 100 parts by weight of the total water-soluble coating composition.

The present invention has been described in more detail below, but is not limited thereto.

Preparation Example 1

Core and shell monomer mixture to be used in each step was prepared by mixing to the composition shown in Table 1.

Monomer I Monomer II MMA 61.0 gBA 33.9 gMAA 21.5 g2-HEA 29.1 g SM 367.4g2-EHA 76.3g

Abbreviations used in the present invention are as follows.

DIW: Deionized Water.

CO-436: Sulfated ammonium salt of alkylphenoxypoly (ethyleneoxy 5 moles) ethanol, manufactured by Rhone-poulenc.

APS: Ammonium Persulfate.

SPS: Sodium Persulfate.

AIBN: 2,2'-azobisisobutyronitrile.

AMPS: Sodium salt of 2-acrylamido-2-methylpropanesulfonide manufactured by Lubrizol.

MMA: Methyl methacrylate.

BA: Butyl methacrylate.

MAA: Methacrylic acid.

2-HEA: 2-hydroxyethyl acrylate.

1,6-HDDA: 1,6-hexanedioldiacrylate.

SM: styrene monomer.

2-EHA: 2-ethylhexyl acrylate.

DVB: 1,4-divinyl benzene.

Example 1 Preparation of Inverted Core / Shell Microgel Emulsion Emulsion Polymers

2.9 g of AMPS was added to the monomer mixture I, followed by mixing.Into a 2-liter four-necked flask equipped with a nitrogen inlet thermometer, a cooler and a stirrer, DIW 630.2g, CO-436 1.0g, and 27.4 g of the monomer mixture I mixed with AMPS were added. The temperature of the reaction portion is raised to 80 ° C. When the temperature is maintained at 80 ° C., nitrogen is injected for 5 minutes to make the reaction part nitrogen, and then nitrogen is removed. 0.42 g of APS was dissolved in 28.3 g of DIW, and then injected into the reactor and aged for 1 hour.

An initiator solution having 0.4 g of SPS dissolved in 28.3 g of DIW was added dropwise for 10 minutes, and the remaining monomer mixture I containing AMPS and 0.5 g of CO-436 dissolved in 198.0 g of DIW were simultaneously dropped for 1 hour and then maintained for 1 hour. . Here, a neutralizer solution in which 1.5 g of NaOH was dissolved in 35.4 g of DIW was added for 20 minutes and then maintained for 10 minutes.

After mixing 2.2 g of DVB and 0.82 g of AIBN in the monomer mixture II, the mixture was dropped for 2 hours and then aged for 1 hour. The reactor is cooled to 40 ° C and a 20% aqueous NaOH solution is added dropwise to adjust the pH to 9.0 to 9.5. Filter off with a 200 mesh filter to remove the core curum and leave for 1 day after packing. The solid content of the final emulsion is prepared by 39.8 parts by weight and a pH of 9.20, a particle size * 1) is 97nm, the viscosity * 2) was 2.8 poise at 1 sec ^-1 at 270 poise, 500 sec ^-1.

Comparative Example 1; Inversion core / shell general emulsion polymer preparation

Into a 2-liter four-necked flask equipped with a nitrogen inlet thermometer, a cooler and a stirrer, DIW 630.2 g, CO-436 1.5 g, and monomer mixture I 27.4 g are introduced and the temperature of the reaction section is raised to 80 ° C. When the temperature is maintained at 80 ° C., nitrogen is injected for 5 minutes to make the reaction part nitrogen, and then nitrogen is removed. 0.42 g of APS was dissolved in 28.3 g of DIW, and then injected into the reactor and aged for 1 hour.

An initiator solution having 0.4 g of SPS dissolved in 28.3 g of DIW was added dropwise for 10 minutes, and then the remaining monomer mixture I and 0.5 g of CO-436 dissolved in 198.0 g of DIW were simultaneously added dropwise for 1 hour and then maintained for 1 hour. Here, a neutralizer solution in which 1.5 g of NaOH was dissolved in 35.4 g of DIW was added for 20 minutes and then maintained for 10 minutes.

After 0.82 g of AIBN is dissolved in the monomer mixture II, the solution is added dropwise to the dropping reactor for 2 hours and aged for 1 hour. The reactor is cooled to 40 ° C and a 20% aqueous NaOH solution is added dropwise to adjust the pH to 9.0 to 9.5. Filter off with a 200 mesh filter to remove the core curum and leave for 1 day after packing. The solids of the finally prepared emulsion was 38.5 parts by weight, pH was 9.20, particle size * 1) was 95nm, viscosity * 2) was 1 pore- ¹ to 120 poise, 500 sec ^-1 to 1.2 poise.

Comparative Example 2; Core / Shell Microgel Emulsion Polymer Preparation

After adding 2.2 g of DVB to the monomer mixture II and stirring, a 2-liter four-necked flask equipped with a nitrogen inlet thermometer, a cooler and a stirrer was added with DIW 630.2 g, CO-436 4.9 g and 27.4 g of the monomer mixture II added with DVB. It inserts and raises the temperature of a reaction part to 80 degreeC. When the temperature is maintained at 80 ° C., nitrogen is injected for 5 minutes to make the reaction part nitrogen, and then nitrogen is removed. 0.42 g of APS was dissolved in 28.3 g of DIW, and then injected into the reactor and aged for 1 hour.

An initiator solution having 0.82 g of SPS dissolved in 28.3 g of DIW was added dropwise for 10 minutes, and the remaining monomer mixture II with DVB and 0.5 g of CO-436 dissolved in 169.7 g of DIW were added dropwise at the same time for 2 hours, and then maintained for 1 hour. .

An initiator solution having 0.4 g of SPS dissolved in 28.3 g of DIW was added dropwise to the reactor for 10 minutes, and the monomer mixture I was added dropwise for 1 hour and then aged for 1 hour. The reactor is cooled to 40 ° C and a 20% aqueous NaOH solution is added dropwise to adjust the pH to 9.0 to 9.5. Filter off with a 200 mesh filter to remove the core curum and leave for 1 day after packing. The solid content of the final emulsion is prepared in the 39.2 weight percent and a pH of 9.30, a particle size * 1) is 102nm, viscosity * 2) was 0.8 poise at ^{1 sec -1 320 poise, 500 sec} -1.

* 1) Particle size: Measured using Malvern's Autosizer Lo-C Model laser light scattering analyzer.

* 2) Viscosity: measured in CS mode using the 600mm cone-plate method of the Haake RS-100 model.

Paint Application Comparison Experiment

Table 2 shows the optimized coating application formulation of the present invention, the coating was prepared by applying the emulsion resin prepared in Example 1 and Comparative Examples 1-2. In the manufacturing process, distilled water, propylene glycol, a dispersant, an antifoaming agent, a pH adjuster, and a texanol are pre-stirred in a millbase step for dispersing the pigment, and titanium dioxide is added, followed by stirring for 90 minutes. The particle size is less than 5 micrometers and the pH is 10.01.

In the finishing step, the emulsion resin, the antifoaming agent, and the crosslinking agent are sequentially added while stirring at low speed, and after 10 minutes of stirring, the paint KU viscosity is adjusted to 80 to 85 KU at 25 ° C. with a thickener and water. Paint solid content is 45-46 weight part, paint pH is 9.0-9.2, and particle size is 10 micrometers or less. When the crosslinking agent was added, the coating was carried out within one day after the preparation of the paint.

Optimized paint application formulations of the present invention step Raw material Parts by weight Mill base Deionized water 2.43 Propylene glycol 2.43 Dispersant 0.33 Antifoam 0.05 pH regulator 0.15 Texanol 1.98 Titanium dioxide 20.03 deadline Emulsion resin 58.35 Antifoam 0.05 Distilled water 11.48 Thickener 1.46 Crosslinking agent 1.26 sum 100.00

* 1) Texanol: products from Eastman, solvent

* 2) Crosslinking agent: Trifunctional aziridine for room temperature crosslinking (CX-100 from Zenca)

The paint physical properties prepared by applying the emulsion resins prepared in Examples and Comparative Examples 1 and 2 are shown in Table 3 below.

Production Example Comparative Example 1 Comparative Example 2 Heat storage ● ● ● Cold and cold storage ● ● ● Glossy (60 °) 86.5 87.0 78.5 Water resistance ● ● × Alkali resistance ● ● × Pollution resistance ● △ ●

●: Good, △: Normal, ×: Poor

Test Methods

1) Seal the paint in a tin can and leave at 50 ℃ for 120 hours, and the KU viscosity should be within ± 8KU.

2) Seal the paint in a tin can and repeat it for 3 hours at -5 ℃ for 16 hours and at 25 ℃ for 8 hours, and the KU viscosity should be within ± 8 KU.

3) Painted with a bird applicator so that the thickness of the wet coating film on the glass plate to 150㎛, dried for 24 hours at 25 ℃ / 55% constant temperature and humidity conditions and measured with a gloss meter.

4) Paint twice with a brush so that the dry film thickness is 80㎛ on the slate plate, dry for 72 hours, and then mask the backside with liquid paraffin. After immersing in fresh water for 24 hours and taking out the film, the gloss holding ratio was measured after 2 hours.

5) Specimen preparation and measuring method is the same as 2) above, but immersed in aqueous calcium hydroxide solution.

6) Paint twice with a brush so that the dry film thickness is 80㎛ on the slate plate, dry for 7 days and stain with three colored pencils. After 1 day, wash with neutral detergent.

When the resin is used as the main resin of the water-based paint, it has the advantages of the paint using the existing microgel emulsion polymer as the main resin, and at the same time, the water resistance is enhanced and can be used as a paint for construction, automobile repair, and plastic. In addition, when the paint is manufactured in the form of crosslinking the outside of the particle of the microgel resin crosslinked inside the particle, the inside and the outside of the particle are crosslinked, so that the crosslinking density of the coating film is higher than that of the non-microgel, so that the stain resistance and the denseness of the coating film are improved. .

Claims (1)

a) i) a monomer containing a single carboxylic acid group consisting of acrylic acid, methacrylic acid, vinylbenzene acid and isopentylbenzene acid, and containing two carboxylic acid groups consisting of crotonic acid, itaconic acid, maleic acid and pmaric acid 10 to 50 parts by weight of a carboxylic acid group-containing monomer, characterized in that selected from the group consisting of monomers; And ii) a vinyl aromatic compound composed of alkyl acrylic acid, cycloalkyl acrylic acid, alkoxyalkyl acrylic acid or methacrylic acid ester having 1 to 18 carbon atoms, hydroxyalkyl acrylic acid or methacrylic acid ester having 2 to 8 carbon atoms, styrene, and derivatives thereof One in the molecule, characterized in that at least one selected from the group consisting of 4 to 9 conjugated diene, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, vinyl chloride, vinyl acetate, and vinyl propionate Essentially comprises 50 to 90 parts by weight of a non-crosslinkable monomer containing an olefin; Optionally iii) divinylbenzene, 1,4-divinylbenzene, arylacrylate, arylmethacrylate, 1,6-hexanediol diacrylate, 1,6-hexanediol dimethacrylate, ethylene glycol diacrylamide Consisting of latex, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol dimethacrylate, butanediol diacrylate, diaryl phthalate, tripropylene glycol dimethacrylate and trimethylolpropane premethacrylate A cross-linking monomer containing two or more olefins and one or two of an anionic reactive emulsifiers are added and reacted to prepare a core emulsion polymer, wherein the core emulsion polymer is prepared. A pseudo water-soluble resin is prepared by adding 0.5 to 1.2 equivalents of a neutralizer to 1 equivalent of carboxylic acid. step; And b) 88 to 99.9 parts by weight of a non-crosslinkable monomer containing one olefin in the molecule; And ii) reacting 0.1 to 12 parts by weight of a crosslinkable monomer containing two or more olefins in the molecule to prepare a shell emulsion polymer.