JPH1180486A - Acrylic-silicone emulsion composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain an acrylic-silicone emulsion compsn. for coating which exhibits a high safety and gives a coating film excellent in weatherability and water resistance by subjecting a mixture contg. a (meth)acrylic ester monomer, a polymerizable emulsifier, a specific polymerizable carboxylic acid, a specific polymerizable light stabilizer, a specific organoalkoxysilane compd. and a specific hindered amine light stabilizer to emulsion polymn. SOLUTION: 100 wt.% monomer mixture comprising 30-96 wt.% (meth)acrylic ester monomer, 1-10 wt.% polymerizable emulsifier, 1-10 wt.% polymerizable carboxylic acid of formula I (wherein R is H or CH3 ; and n is 1-4), formula II (wherein n is 1-10) or formula III, 1-20 wt.% benzophenone- or benzotriazole- type polymerizable light stabilizer and 1-30 wt.% organoalkoxysilane compd. having at least one glycidyl group in the molecule and 0.1-5 wt.% hindered amine light stabilizer having a base constant (pKb) of 8 or higher is subjected to emulsion polymn.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an emulsion composition for paints used for coating building materials and the like, and more particularly to an acrylic silicone emulsion composition excellent in weather resistance, chemical resistance, water resistance and the like.

[0002]

2. Description of the Related Art In the coating and painting of architectural and building materials, not only does the base of concrete, mortar, wood, etc. be protected, but also the design appearance and beautiful decorative appearance formed by painting do not change over a long period of time. It is desired to be continued, and from such a viewpoint, acrylic silicone resin paint and fluororesin paint are usually used. However, these are paints based on organic solvents and are not preferred from the viewpoint of environmental protection and energy saving.

[0003] Therefore, as a safe and environmentally friendly paint,
Water-based emulsion paints such as acrylic resin emulsion paints have been developed and used, but excellent basic properties required for paints such as water resistance, alkali resistance, and weather resistance have been found to be well-balanced. Absent.

[0004] Therefore, in order to improve these properties, an acrylic silicone emulsion composition obtained by converting an acrylic resin emulsion into a silicone has been proposed. However, at the stage of preparing the acrylic emulsion composition, for example, γ-methacryloyloxy is used. Since the silicone is formed by copolymerizing a radically polymerizable silane compound such as propyltrimethoxysilane, the alkoxysilane portion is hydrolyzed during the polymerization or storage of the acrylic emulsion and crosslinked in the emulsion particles. As a result, not only the storage stability is deteriorated, and also the film forming property is deteriorated, but also when the coating film is formed, sufficient fusion (coalescence) between the emulsion particles and crosslinking do not proceed, and The leveling property at the time of formation is reduced, making it difficult to achieve gloss,
The expected weather resistance was not obtained.

[0005] As a means for silicone conversion, copolymerization of a silicone macromonomer has been proposed (PA
INT & COATING BUSINESS Vol.
6, 1996), the silicone polymer segment does not crosslink, and when applied to building materials, the blocking property may be degraded due to the silicone segment. In addition, touch-up is required for painting building materials, but the recoating property is poor, which is not preferable.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of the prior art and is a highly safe acrylic silicone emulsion composition, which has particularly excellent weatherability and water resistance and excellent coating performance. An emulsion resin for paint is provided.

[0007]

In order to solve the above problems, the present invention has the following arrangement. That is, the present invention relates to (meth) acrylic acid ester monomer (1)
96% by weight, alone or as a mixture of two or more of the polymerizable carboxylic acids (2) of the formula I, II or III
10 to 10% by weight, 1 to 10% by weight of a polymerizable emulsifier (3), 1 to 20% by weight of a benzophenone-based or benzotriazole-based polymerizable light stabilizer (4), and at least one glycidyl group in one molecule. 100% by weight of a total of a monomer mixture comprising 1 to 30% by weight of an organoalkoxysilane compound (5), and a hindered amine light stabilizer (HALS) (6) having a base constant (PKb) of 8 or more;
An acrylic silicone emulsion composition obtained by emulsion-polymerizing a mixture containing -5% by weight.

[0008]

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[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Meth) acrylic acid ester monomers (1) include methyl acrylate, ethyl acrylate, n-butyl acrylate, isobutyl acrylate, tertiary butyl acrylate, cyclohexyl acrylate, acrylic 2-ethylhexyl acrylate, lauryl acrylate, tricyclodecyl acrylate, isobornyl acrylate, methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tertiary butyl methacrylate, cyclohexyl methacrylate, methacrylic acid 2 -Ethylhexyl, lauryl methacrylate, tricyclodecyl methacrylate, isobornyl methacrylate and the like. These monomers may be used alone or as a mixture of two or more.

The (meth) acrylate monomer is 30
~ 96% by weight is used. If less than 30% by weight,
When a paint is used, the coating film performance such as toughness, elongation, gloss, and chemical resistance is deteriorated. When it exceeds 96% by weight, weather resistance and adhesion are deteriorated, which is not preferable.

Examples of the polymerizable carboxylic acid (2) represented by the formula I, II or III include acrylic acid esters of hydroxypropionic acid, succinic acid esters of 2-hydroxyethyl (meth) acrylate, and 2-acryloyloxyethyl. And phthalic acid. These polymerizable carboxylic acids may be used alone or as a mixture of two or more.

These polymerizable carboxylic acids are used in an amount of 1 to 10% by weight. If the amount is less than 1% by weight, the adhesion, the film-forming property, and the cross-linking property of the coating film deteriorate. If it is used in an amount exceeding 10% by weight, the water resistance, alkali resistance and the like of the coating film deteriorate, and the weather resistance (particularly, the resistance to discoloration and fading) deteriorates.

As the polymerizable carboxylic acid (2), a normal α, β-unsaturated carboxylic acid such as acrylic acid or methacrylic acid is used in an amount not exceeding 30% by weight of the total amount of the polymerizable carboxylic acid. It is also possible. When the α, β-unsaturated carboxylic acid is used in an amount exceeding 30% by weight of the total amount of the polymerizable carboxylic acid (2), the water resistance and alkali resistance of the coating film may be deteriorated.

Examples of the polymerizable emulsifier (3) include polyethylene glycol monoacrylates and methacrylates having various molecular weights (different EO addition moles), polyoxyethylene alkylphenyl ether acrylates, polyoxyethylene alkylphenyl ether methacrylates Esters, ammonium 2-acryloyloxyethylsulfonate, sodium 2-methacryloyloxyethylsulfonate, monomaleic acid esters of polyoxyethylene glycol and derivatives thereof, polyoxyalkylene alkyl ether phosphoric esters, and the like. The acidic emulsifier may be used alone or as a mixture of two or more.

In particular, when the polymerizable emulsifier has an acrylic or allylic functional group and is represented by the formula IV or V, the coagulum at the time of preparation of the acrylic silicone resin emulsion is reduced, and more stable. This is preferable in that a novel acrylic silicone emulsion composition can be obtained.

[0016]

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The polymerizable emulsifier represented by the formula IV is bis (polyoxyethylene polycyclic phenyl ether) (meth)
These are collectively referred to as acrylated sulfate salts, and these may be appropriately selected.

Examples of the polymerizable emulsifier represented by the formula V include those in which X is H or SO ₃ NH _{4. In} the present invention, those having SO ₃ NH ₄ are preferred because of good emulsification and dispersion. More preferred.

When preparing the acrylic silicone emulsion composition, the polymerizable emulsifier (3) is used in an amount of 1 to 10% by weight.
used. If the amount is less than 1% by weight, coagulum will increase during emulsion polymerization, and mechanical storage stability as a coating will be insufficient. If the amount exceeds 10% by weight, the basic properties such as water resistance and alkali resistance of the coating film when it is used as a coating material are deteriorated.

Examples of the benzophenone-based or benzotriazole-based polymerizable light stabilizer (4) include 2-hydroxy-4- (3-methacryloxy-2-hydroxypropoxy) benzophenone and 2-hydroxy-4- (3
-Acryloxy-2-hydroxypropoxy) benzophenone, 2,2'-dihydroxy-4- (3-methacryloxy) -2-hydroxypropoxy) benzophenone, 2,2'-dihydroxy-4- (3-acryloxy ) -2-Hydroxypropoxy) benzophenone and the like, and these polymerizable light stabilizers can be used alone or as a mixture of two or more.

In the present invention, in particular, the polymerizable light stabilizer is represented by the formula V
When represented by I, the storage stability of the acrylic silicone emulsion composition and the long-term gloss stability of the coating film are excellent, and the generation of coagulum when the acrylic silicone emulsion is emulsion-polymerized and adjusted is extremely small. It is preferable in that the acrylic silicone emulsion composition can be obtained without being coagulated or gelled.

[0022]

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Examples of the polymerizable light stabilizer represented by the formula VI include 2- (2'-hydroxy-5'-acryloyloxyethylphenyl) -2H-benzotriazole,
(2'-Hydroxy-5'-methacryloyloxyethylphenyl) -2H-benzotriazole.

The benzophenone-based or benzotriazole-based polymerizable light stabilizer (4) is used in an amount of 1 to 20% by weight when the acrylic silicone emulsion is emulsion-polymerized. If the amount is less than 1% by weight, sufficient weather resistance of the coating film as a coating cannot be obtained. If the content exceeds 20% by weight, the storage stability of the acrylic silicone emulsion composition is deteriorated, and the coating film is liable to be yellowed in a weather resistance test, and the coating cost is extremely high.

Examples of the organoalkoxysilane compound (5) having at least one glycidyl group in one molecule include γ-glycidoxypropyltrimethoxysilane and γ-glycidoxypropyltrimethoxysilane.
-Glycidoxypropyltriethoxysilane, γ-glycidoxypropyltriisopropyloxysilane, γ-
Glycidoxypropylmethyldiethoxysilane, β-
(3,4-epoxycyclohexyl) ethyldimethoxysilane and the like, and these compounds may be used alone or as a mixture of two or more. Further, (partial) condensates of these compounds may be used.

The organoalkoxysilane compound (5) having at least one glycidyl group in one molecule is 1 to
Used at 30% by weight. If the amount is less than 1% by weight, the crosslinkability of the coating film becomes low, and there is a concern about long-term weather resistance. Further, satisfactory solvent resistance and stain resistance cannot be obtained. If used in excess of 30% by weight, coagulation,
It is not preferable because gelation easily occurs. In addition, the coating film is hard and brittle, and cracks and peeling are likely to occur, which is not preferable.

In the present invention, a hydrolyzable silicone compound other than the organoalkoxysilane compound (5) having at least one glycidyl group in one molecule can be used in combination. Examples of the hydrolyzable silicone compound that can be used in combination include γ-mercaptopropyltrimethoxysilane, methyltrimethoxysilane, methyltriethoxysilane, vinyltriacetoxysilane, γ-chloropropyltrimethoxysilane, vinyltrimethoxysilane, dimethyldimethoxysilane , Γ-mercaptopropylmethyldimethoxysilane, hydroxypropyltrimethoxysilane, ureidopropyltrimethoxysilane, phenyltrimethoxysilane, phenyltriethoxysilane,
Examples include phenylmethyldimethoxysilane, phenylmethyldiethoxysilane, dimethyldiethoxysilane, and their (partial) condensates, which have a radical copolymerizability with the (meth) acrylate monomer (1). It does not have.

The hindered amine light stabilizer (HALS) (6) having a base constant (PKb) of 8 or more includes 1-
[2- [3- (3,5-Di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl] -4- [3
-(3,5-di-t-butyl-4-hydroxyphenyl) propionyloxy] -2,2,6,6-tetramethylpiperidine, 8-acetyl-3-dodecyl-7,
7,9,9-Tetramethyl-1,3,8-triazaspiro [4,5] decane-2,4-dione and the like. These HALSs may be used alone or in a mixture of two or more.

In preparing these acrylic silicone emulsion compositions, HALS is preferably dissolved in a monomer such as a (meth) acrylic acid ester monomer and used from the time of emulsion polymerization. By doing so, the addition is easy and an effect more excellent in weather resistance is exhibited.

When PKb is less than 8, coagulum is liable to be generated during preparation of the acrylic silicone emulsion composition, and gelation is liable to occur. Furthermore, even if the acrylic silicone emulsion composition is prepared, the emulsion has poor storage stability and is not practical.

These HALS are used in an amount of 0.1 to 5% by weight based on the acrylic silicone emulsion.
When the content is less than 0.1% by weight, the effect of contributing to weather resistance is not so great. When the content exceeds 5% by weight,
The particle size of the obtained acrylic silicone emulsion composition becomes large, and the film forming property, the uniformity of the coating film, and the glossiness tend to deteriorate.

The acrylic silicone emulsion composition is prepared, for example, in ion-exchanged water at a polymerization temperature of 30 to 100.
℃, persulfate compounds such as ammonium persulfate and potassium persulfate as polymerization initiators, organic oxides such as tertiary butyl hydroperoxide, and organic azo polymerization initiators such as α, α'-azobisisobutyronitrile And the like, the above-mentioned (meth) acrylate monomer, polymerizable carboxylic acid, polymerizable emulsifier, polymerizable light stabilizer, and organoalkoxy having at least one glycidyl group in one molecule. It is adjusted by emulsion polymerization of a mixture of a silane compound and a hindered amine light stabilizer (HALS) having a PKb of 8 or more. An organoalkoxysilane compound having at least one glycidyl group in one molecule does not undergo radical copolymerization during emulsion polymerization, but it must be present in a place where other raw materials (polymerizable compounds) undergo emulsion copolymerization. HALS having a PKb of 8 or more does not similarly undergo radical copolymerization, but other raw materials (polymerizable compounds)
Is preferably present in the emulsion polymerization.

The obtained acrylic silicone emulsion composition preferably has a weight average molecular weight of 100,000 or more in view of toughness, weather resistance and chemical resistance of the coating film.
The particle diameter of the dispersed polymer is preferably from 50 to 300 nm from the viewpoint of coating viscosity, film forming property, uniformity of coating film, and drying property, and the ratio of weight average particle diameter / number average particle diameter is 3 or less, more preferably A value of 2 or less is preferred from the viewpoint of preventing aggregation when preparing the acrylic silicone emulsion composition, uniformity of the coating film, and weather resistance.

Now, the present invention will be described in further detail with reference to Examples. In addition, each evaluation in an Example shall measure and judge by the following methods.

Here, the paint used for the test was 2,2 as a film-forming aid with respect to the acrylic silicone emulsion composition.
A product obtained by adding 10 PHR of 2,4-trimethyl-1,3-pentanediol monoisobutyrate (corresponding to product CS-12 of Chisso Corporation) was used.

1. Storage stability About 80 ml of the acrylic silicone emulsion was placed in a 100 ml glass bottle, sealed, and allowed to stand at 40 ° C. for one month. One month later, the state of the acrylic silicone emulsion was visually determined.

：: Good without aggregation, thickening, sedimentation, separation, etc. Pass. ×: Viscosity, separation, sedimentation, etc., more than twice that of before the test are observed. failure.

2. Weather resistance (performed in accordance with JIS K 5400) A paint was applied to a JIS A 5413 asbestos cement pearlite plate so that the coating thickness became about 50 μm, and 1
After drying for 0 minutes, the material was forcibly dried at 80 ° C. for 30 minutes. A coating material was further applied on this coated plate so that the thickness of the coating film became about 50 μm, dried at room temperature for 10 minutes, and then forcibly dried at 80 ° C. for 30 minutes. This was dried at room temperature for 2 weeks.

The dried coated plate was subjected to an accelerated weathering test for 4000 hours using a sunshine weatherometer (SWOM). The gloss retention (expressed as gloss after accelerated weather resistance test / gloss before test × 100) is 80% or more (the higher the gloss retention, the better the weather resistance) and the color difference (Δ
A case where E) is 0.5 or less is regarded as a pass. Otherwise, it is rejected.

3. Apply the water-resistant paint to the glass plate with a 10 mil applicator,
After drying at room temperature for 10 minutes, it was forcibly dried at 80 ° C. for 30 minutes. The coated plate is dried at room temperature for 5 days, immersed in warm water at 60 ° C., and subjected to a test for 24 hours. Further, while the coated plate is immersed in the warm water, the container containing the warm water is left to cool naturally, and the test is continued for 24 hours. The state of the coating film after the test is observed and evaluated.

○: There is no change in the state of the coating film, which is the same as before the test.
Pass. Δ: The coating film is slightly whitened, but returns to its original state after drying. Pass. ×: The coating film is whitened. Does not recover after drying. failure.

[0042]

EXAMPLES In the following Examples and Comparative Examples, each raw material in the table is supposed to be carried out at 5 times the indicated weight (g), and the meanings of the abbreviations in the table are as follows. is there.

Β-CEA: polymerizable carboxylic acid (corresponding to formula I). A mixture of acrylic acid / acrylic acid ester of hydroxypropionic acid / acrylic acid ester of di (hydroxypropionic acid ester) / acrylic acid ester of tri (hydroxypropionic acid ester) (Shipomer β-CEA manufactured by Rhone Poulin Co., Ltd.) Equivalent).

AN-MS-60: Polymerizable emulsifier (formula IV
Equivalent). One of bis (polyoxyethylene polycyclic phenyl ether) (meth) acrylated sulfate ester salts (corresponding to Antox MS-60 manufactured by Nippon Emulsifier Co., Ltd.).

SE-10N: polymerizable emulsifier (corresponding to formula V) (Adekaria Soap SE-10 manufactured by Asahi Denka Co., Ltd.)
N).

DBS: sodium dodecylbenzenesulfonate. Non-polymerizable emulsifier.

RUVA: polymerizable light stabilizer (corresponding to formula VI). 2- (2'-hydroxy-5'-methacryloyloxyethylphenyl) -2H-benzotriazole (corresponding to RUVA-93 manufactured by Otsuka Chemical Co., Ltd.).

LA-82: Hindered amine polymerizable light-stable monomer (ADK STAB LA-8 manufactured by Asahi Denka Co., Ltd.)
2).

GPS: an organoalkoxysilane compound having at least one glycidyl group in one molecule. γ
Glycidoxypropyltrimethoxysilane.

MPS: an organoalkoxysilane compound having no at least one glycidyl group in a molecule.
Polymerizable organoalkoxysilane compounds. γ-methacryloyloxypropyltrimethoxysilane.

QP8-5314: Other silicone compounds that can be added. Silicone compounds containing phenyltrimethoxysilane and phenyl-methyl-dimethoxysilane as main components (corresponding to product QP8-5314 of Dow Corning Toray Silicone Co., Ltd.).

LS: Hindered amine light stabilizer (HALS) (5) having a base constant (PKb) of 8 or more. 8-acetyl-3-dodecyl-7,7,9,9-tetramethyl-
1,3,8-Triazaspiro [4,5] decane-2,4
-Dione (corresponding to Sanol LS-440 manufactured by Sankyo).

Example 1 400 g of ion-exchanged water was placed in a 2 L four-necked flask equipped with a stirrer, a thermometer, a condenser, and a monomer supply pump.
Prepare.

Separately, 150 g of ion-exchanged water and Table 1
Using a homogenizer (Maximum homogenizer manufactured by Nippon Seiki Co., Ltd.)
Emulsify at 000 rpm for 10 minutes. (This is referred to as EM-1.) 25 g of ion-exchanged water, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide]
(Azo-based polymerization initiator) 5 g of a mixture is added to EM-1, and the mixture is stirred to dissolve the polymerization initiator (this is referred to as EM-2).

10% by weight of EM-2 is charged into a flask and heated to 80 ° C. for 30 minutes while stirring. 80
After continuing the polymerization at 30 ° C for 30 minutes, the remaining EM-2 is fed into the flask by a monomer feed pump in 3 hours. After the completion of the supply, the polymerization is further continued for one hour and then cooled to 30 ° C.

While stirring the acrylic silicone emulsion, the pH (25 ° C.) is adjusted to 8.0 to 9.5 (the neutralization ratio of the copolymerized carboxylic acid is from 60% to 80%).
%) 25% ammonia water is gradually added. Thus, the acrylic silicone emulsion composition of Example 1 is obtained.

Tables 6 and 7 show the characteristic values and test results of the obtained acrylic silicone emulsion compositions.

Examples 2 to 8 and Comparative Examples 1 to 5 Production was carried out in the same manner as in Example 1 except that the raw material compositions were changed as shown in Tables 1 to 5. (Comparative Examples 4 and 5 gelled during the emulsion polymerization and could not produce an emulsion. The one to which QP8-5314 was added was obtained by neutralizing the acrylic silicone emulsion and then stirring the emulsion while stirring the emulsion. Are gradually added.) The characteristic values and test results of the obtained acrylic silicone emulsion composition are shown in Tables 6 and 7.

[0059]

[Table 1]

[0060]

[Table 2]

[0061]

[Table 3]

[0062]

[Table 4]

[0063]

[Table 5]

[0064]

[Table 6]

[0065]

[Table 7]

[0066]

The acrylic silicone emulsion composition of the present invention gives a coating film having remarkably excellent weather resistance and water resistance.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI C08F 220/12 C08F 220/12 220/26 220/26 290/06 290/06

Claims (3)

[Claims] 1. A (meth) acrylate monomer (1)
30 to 96% by weight, 1 to 10% by weight of a polymerizable carboxylic acid (2) represented by the formula I, II or III alone or a mixture of two or more thereof, 1 to 10% by weight of a polymerizable emulsifier (3), A total of 1 to 20% by weight of a benzophenone-based or benzotriazole-based polymerizable light stabilizer (4) and 1 to 30% by weight of an organoalkoxysilane compound (5) having at least one glycidyl group in one molecule.
And a base constant (PKb) of 8% by weight.
Hindered amine light stabilizer (HALS) (6)
An acrylic silicone emulsion composition obtained by emulsion polymerization of a mixture containing 0.1 to 5% by weight. Embedded image Embedded image Embedded image 2. The acrylic silicone emulsion composition according to claim 1, wherein the polymerizable emulsifier (3) is represented by Formula IV or Formula V, but is a single compound or a mixture of two or more compounds. Embedded image Embedded image 3. The acrylic silicone emulsion composition according to claim 1, wherein the benzophenone-based or benzotriazole-based polymerizable light stabilizer (4) is represented by the formula VI. Embedded image