JPH0912906A - Production of curable emulsion composition - Google Patents

Abstract

PURPOSE: To obtain a curable emulsion composition excellent in curing property and useful for coating, adhesive, etc., by mixing an aqueous emulsion composed of a hydrolyzable silyl group-containing vinyl polymer with an aqueous emulsion composed of an acidic group-containing vinyl polymer. CONSTITUTION: Preferably 80-60wt.% aqueous emulsion comprising a hydrolyzable silyl group-containing vinyl polymer obtained by (A) a process for emulsifying and dispersion a hydrolyzable silyl group-containing vinyl monomer, a vinyl monomer copolymerizable with the monomer and an oil-soluble free radical polymerization initiator in an aqueous medium in the presence of a free radical- polymerizable surfactant of the formula Z-(AO)n -Y [Z is a constituent unit containing a free radical-polymerizable group; AO is an oxyalkylene; (n) is an integer of >=2; Y is an ion dissociating group] and pH buffer and (B) a process for feeding an aqueous emulsifying dispersing element obtained in the process A to an aqueous medium under stirring and polymerizing the monomer is mixed with preferably 20-40wt.% aqueous emulsion comprising an acidic group-containing vinyl polymer.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a curable emulsion composition comprising a vinyl polymer having a hydrolyzable silyl group. The emulsion composition obtained by the present invention is a paint or an adhesive. It can be preferably used for applications such as.

[0002]

2. Description of the Related Art A curable polymer having a hydrolyzable silyl group represented by an alkoxysilyl group has been conventionally used as an adhesive, a sealing material, a paint or a solvent-type product dissolved in an organic solvent. Widely used in applications such as coating agents. However, in these fields of application, in order to avoid environmental pollution by an organic solvent, an aqueous material that does not use an organic solvent is required, and a curable polymer having a hydrolyzable silyl group (hereinafter referred to as a hydrolyzable silyl group is used). A degradable silyl group-containing polymer) is also being investigated for aqueous emulsification.

Since a hydrolyzable silyl group-containing polymer originally has a property of being crosslinked while being hydrolyzed, it is not easy to obtain a stable aqueous emulsion, and various proposals for aqueous emulsification have been made. Has been done. As an example, even if a stable aqueous emulsion can be obtained, there are some that are inferior in curability. In such a case, a method of curing using an organotin compound as a curing accelerator has been proposed (special feature: Kaihei 3-227312).

However, a composition obtained by mixing an aqueous emulsion comprising a hydrolyzable silyl group-containing polymer and an organic tin compound has poor storage stability and can be used only at room temperature for a short time after mixing. As a means for improving this point, a method of adding an organometallic compound emulsified with a surfactant as a curing accelerator has also been proposed (JP-A-6-2).
No. 28367). According to the method described in the above publication, the stability of an aqueous emulsion composed of a hydrolyzable silyl group-containing polymer at room temperature was considerably improved, but at high temperature, it can still be used for only a short period of time, and is more excellent in storage stability. Is currently required. An object of the present invention is to provide a method for producing an aqueous emulsion comprising a hydrolyzable silyl group-containing polymer and having excellent storage stability, which can form an excellent cured coating film.

[0005]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, have completed the present invention. That is, the first invention in the present invention is to produce an aqueous emulsion comprising a hydrolyzable silyl group-containing vinyl polymer by the following step [1] and step [2], and to prepare an aqueous emulsion comprising this and an acidic group-containing vinyl polymer. A method for producing a curable emulsion composition, which comprises mixing Step [1]: General formula Z- (AO) n-Y (In the formula, Z is a structural unit containing a radically polymerizable group, AO is an oxyalkylene group, n is an integer of 2 or more, and Y is an ion dissociable group. A vinyl monomer having a hydrolyzable silyl group, a vinyl monomer copolymerizable with the monomer, and an oil-soluble solvent in the presence of a radically polymerizable surfactant represented by A step of emulsifying and dispersing a radical polymerization initiator in an aqueous medium. Step [2]: A step of continuously or intermittently supplying the aqueous emulsified dispersion obtained in the above step [1] into an agitated aqueous medium to polymerize the monomer in the medium. Further, the second invention is the production of the above curable emulsion composition in which the ratio of the hydrolyzable silyl group-containing vinyl polymer and the acid group-containing vinyl polymer is 80 to 60% by weight of the former and 20 to 40% by weight of the latter. Is the way.

The present invention will be described in more detail below. In the step [1], as described above, the vinyl monomer having a hydrolyzable silyl group, the vinyl monomer copolymerizable with the monomer, and the oil-soluble radical polymerization initiator are emulsified in an aqueous medium. Disperse, but at that time, as an emulsifier,
The general formula Z- (AO) n-Y (wherein Z is a structural unit containing a radically polymerizable group, AO is an oxyalkylene group, n
Is an integer of 2 or more, and Y is an ionic dissociative group). Preferred Z in the general formula Z- (AO) n-Y is
Aromatic hydrocarbon group, an alkyl-substituted aromatic hydrocarbon group, a structural unit in which a radically polymerizable group is bonded to a hydrophobic group such as a higher alkyl group or an alicyclic hydrocarbon group, a preferable radically polymerizable group is (Meth) allyl group, propenyl group, butenyl group and the like can be mentioned.

The preferred ionicity of the radically polymerizable surfactant in the present invention is an anion, and specific examples of preferred Y include --SO ₃ Na, --SO ₃ NH ₄ ,
_{-COONa, -COONH 4, -PO 3 Na} 2 and -PO ₃ (NH _{4) 2} and the like, more preferably -
SO ₃ Na or -SO ₃ is NH _4. Group (AO) n
The value of n in is preferably 300 or less, more preferably 5 to 50. When n is less than 5, the stability of the hydrolyzable silyl group tends to be insufficient, while when n exceeds 50, the physical properties of the coating film formed from the curable emulsion obtained tend to deteriorate. As the unit A in the group (AO) n, that is, the alkylene group, an ethylene group or a propylene group is preferable.

Specific examples of the radical-polymerizable surfactant include compounds represented by the following chemical formulas 1, 2 and 3. R in Chemical formula 1 or Chemical formula 2 is 6 to 6 carbon atoms.
Eighteen linear or branched alkyl groups are preferred. Chemical 3
As R2 therein, an alkyl group having 8 to 24 carbon atoms is preferable, and R1 is a hydrogen atom or a methyl group. Further, Y in Chemical Formulas 1 to 3 is an ion dissociative group, and specific examples thereof are as described above.

[0009]

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[0010]

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[0011]

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The preferred amount of the radically polymerizable surfactant used in the present invention is 0.5 to 10 relative to the total amount of the vinyl monomer having a hydrolyzable silyl group and the copolymerizable monomer described later. % By weight. When the amount of the radical-polymerizable surfactant is less than 0.5% by weight, the aqueous emulsion dispersion formed in the step [1] tends to be unstable, while 1
If it exceeds 0% by weight, the physical properties of the coating film formed by the obtained polymer emulsion composition are likely to be impaired.

In the present invention, a pH buffer is used to suppress the hydrolysis of the hydrolyzable silyl group. pH
As the buffering agent, a buffering agent suitable for keeping the pH of the aqueous medium in the aqueous emulsified dispersion obtained in the step [1] at 6 to 10 is preferable, and specifically, sodium hydrogen carbonate, potassium hydrogen carbonate, Monosodium phosphate, monopotassium phosphate, disodium phosphate, trisodium phosphate,
Examples thereof include sodium acetate, ammonium acetate, sodium formate, and the like, and more preferably, addition of a small amount of pH
Is sodium hydrogencarbonate that stabilizes. A suitable amount of the pH buffer used is 0.01 to 5% by weight based on water. If necessary, a weak alkaline compound such as ammonia, monoethylamine, triethylamine, or ethanolamine may be used as a pH adjuster together with the pH buffer.

The vinyl monomer having a hydrolyzable silyl group in the present invention (hereinafter referred to as silyl monomer) is vinylmethyldimethoxysilane, vinyltrimethoxysilane, vinyltriethoxysilane, vinyltris (β-methoxyethoxy). ) Silane, γ-methacryloxypropylmethyldimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-methacryloxypropylmethyldiethoxysilane, γ-acryloxypropyltrimethoxysilane, γ-acryloxypropylmethyldimethoxysilane and γ. Radical polymerizable monomers having an alkoxysilyl group such as acryloxypropyltriethoxysilane are preferred.

The vinyl monomer copolymerizable with the silyl-based monomer (hereinafter referred to as a copolymerizable monomer) includes methyl (meth) acrylate, ethyl (meth) acrylate,
(Meth) such as n-butyl (meth) acrylate, isobutyl (meth) acrylate, cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, lauryl (meth) acrylate, stearyl (meth) acrylate, etc. Alkyl acrylate; 2-methoxyethyl (meth) acrylate, 2-ethoxyethyl (meth) acrylate,
2-Methoxypropyl (meth) acrylate, 2-ethoxypropyl (meth) acrylate, (meth) acrylic acid 2
-(Meth) acrylic acid esters such as hydroxyethyl, 2-hydroxypropyl (meth) acrylate, perfluoroalkyl (meth) acrylate, glycidyl methacrylate, N, N-diethylaminoethyl (meth) acrylate; vinyl acetate, Examples thereof include vinyl propionate, styrene, α-methylstyrene and the like. Preferred copolymerizable monomers are alkyl (meth) acrylate having an alkyl group having 4 to 8 carbon atoms, 2-hydroxyalkyl (meth) acrylate having an alkylene group having 2 to 3 carbon atoms, and (meth ) Glycidyl acrylate and styrene.

The proportion of the silyl monomer and the copolymerizable monomer used is 0.5 to 50% by weight of the silyl monomer and the copolymerizable monomer 99. 5-50
% By weight is preferred. More preferably, the silyl-based monomer is 1 to 30% by weight and the copolymerizable monomer is 99 to 70% by weight.
It is. When the proportion of the silyl monomer is less than 0.5% by weight, the surface hardness of the film formed from the polymer emulsion composition containing the hydrolyzable silyl group-containing vinyl polymer as a component is insufficient. If it exceeds 50% by weight, the stability of the emulsion composition is lowered.

The polymerization initiator to be used for the polymerization of the silyl monomer and the copolymerizable monomer is an oil-soluble polymerization initiator, and specifically has a solubility in water at 20 ° C. of 10% by weight or less. Those preferred are as the polymerization initiator,
2,2'-azobisisobutyronitrile, 2,2'-azobis-2,4-dimethylvaleronitrile, 1-azobis-1-cyclohexanecarbonitrile and dimethyl-2,2'-azobisisobutyrate, etc. Azo initiators, and organic peroxides such as lauroyl peroxide, benzoyl peroxide, dicumyl peroxide, cyclohexanone peroxide, di-n-propylperoxydicarbonate and t-butylperoxypivalate. .

The amount of the polymerization initiator used is preferably 0.1 to 10% by weight, based on the total amount of the monomers used, and 0.5 to 5%.
% Is more preferred. The above-mentioned polymerization initiator is preferably dissolved in a monomer mixture liquid comprising a silyl-based monomer and a copolymerizable monomer, and is aqueous emulsified together with the monomer. As a method for aqueous emulsification of the monomer and the polymerization initiator, the ratio of the aqueous medium containing the radically polymerizable surfactant and the pH buffer in an amount of 30 to 150 parts by weight per 100 parts by weight of the monomer solution. It is preferable that the mixture is mixed and the resulting mixed liquid is finely emulsified by a homomixer, a homogenizer, ultrasonic waves, or the like. The smaller the particle size of the dispersed particles in the aqueous emulsified dispersion obtained by the above method, the more preferable it is. Specifically, the average particle size is 1 μm.
Further preferably, it is 0.5 μm or less. When the particle size of the dispersed particles exceeds 1 μm, the amount of coarse particles contained in the resulting hydrolyzable silyl group-containing polymer emulsion increases.

Next, in step [2], the above aqueous emulsion dispersion (hereinafter referred to as a monomer emulsion) is polymerized in an aqueous medium to obtain an aqueous emulsion comprising a hydrolyzable silyl group-containing vinyl polymer. At the time of polymerization, an aqueous medium is charged in a polymerization vessel in advance, and the monomer emulsion is gradually fed into the aqueous medium with stirring. A preferable method of supplying the monomer emulsion to the polymerization container is a method of gradually dropping it from a dropping funnel. The lower limit of the amount of the aqueous medium to be charged in the polymerization vessel in the above polymerization is the amount that can be stirred by a stirrer, but it is preferably 10 to 50 parts by weight per 100 parts by weight of the monomer emulsion.

An emulsifier is preferably added at a concentration of 0.5 to 5% by weight to the aqueous medium charged in advance in the polymerization vessel. As the emulsifier, the above-mentioned general formula Z- (AO) _{n is used.}
Radical polymerizable surfactant represented by -Y, sodium stearate, potassium laurate, sodium lauryl sulfate, sodium alkylbenzenesulfonate, sodium xylenesulfonate, sodium alkylnaphthalenesulfonesan, sodium polyoxyethylene nonylphenyl ether sulfate, etc. Of the anionic surfactants are preferred. Particularly preferably, the general formula Z- (AO) _n-
It is a radically polymerizable surfactant represented by Y. The polymerization temperature varies depending on the polymerization initiator used, but is usually 40 to
The temperature is preferably 100 ° C, more preferably 70 to 90 ° C.

By the above polymerization, the average particle size is 0.1 to 0.5 μm.
An aqueous emulsion of a hydrolyzable silyl group-containing vinyl polymer (hereinafter referred to as a silyl emulsion) in which the polymer particles of m are stably emulsified and dispersed is obtained. The aqueous emulsion thus obtained is characterized by excellent storage stability as compared with an aqueous emulsion of a hydrolyzable silyl group-containing vinyl polymer produced by a conventionally known method. Incidentally, in the aqueous emulsion polymerization of the above-mentioned monomer, the oil-soluble polymerization initiator is contained in the dispersed particles of the monomer emulsion, and the polymerization takes place in each fine particle dispersed in the aqueous medium. . Such a polymerization method is generally called a microsuspension polymerization method, and is distinguished from an emulsion polymerization method in which a water-soluble initiator causes polymerization in a micelle formed by an emulsifier.

Next, an aqueous emulsion comprising an acidic group-containing vinyl polymer (hereinafter referred to as acidic group-containing emulsion) will be described. In the present invention, a silyl emulsion produced by the above method is mixed with an acidic group-containing emulsion to form a coating film having extremely excellent solvent resistance and water resistance as compared with a coating film formed from the former alone. An emulsion composition capable of forming

The acidic group in the acidic group-containing vinyl polymer in the present invention is preferably a carboxyl group or a phosphoric acid group. As the acidic group-containing vinyl polymer, a vinyl monomer having such an acidic group and another vinyl group are used. A polymer obtained by copolymerizing monomers is preferable. Examples of the vinyl monomer having an acid group include carboxyl group-containing monomers such as (meth) acrylic acid, 2- (meth) acryloyloxyethylsuccinic acid, and 2- (meth) acryloyloxyethylphthalic acid; mono (2 Examples thereof include phosphoric acid group-containing monomers such as acryloyloxyethyl) acid phosphate and mono (2-methacryloyloxyethyl) acid phosphate, and carboxyl group-containing monomers are preferable.

As the vinyl monomer to be copolymerized with the acidic group-containing vinyl monomer, the same monomer as the copolymerizable monomer which has already been described for the hydrolyzable silyl group-containing polymer can be used. Furthermore, it is preferable to use a crosslinkable monomer such as divinylbenzene, diallyl phthalate, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate and tetramethylene glycol di (meth) acrylate together.

The preferable ratio of the acidic group-containing monomer unit in the acidic group-containing vinyl polymer is 0.5 to 20% by weight based on the total amount of all the monomer units. When the amount of the acidic group-containing monomer unit is less than 0.5% by weight, the mechanical strength of the coating film obtained from the polymer emulsion composition is low, while when it exceeds 20% by weight, the polymer emulsion composition is Stability tends to decrease. The acidic group-containing emulsion is obtained by copolymerizing the above-mentioned monomers by a known emulsion polymerization method,
Alternatively, it can also be obtained by neutralizing a copolymer obtained by solution polymerization using a hydrophilic solvent such as isopropyl alcohol with a basic substance such as an organic amine, and then emulsifying and dispersing in water. The same microsuspension polymerization method as that used for obtaining the silyl emulsion may be adopted.

In the present invention, the ratio of the hydrolyzable silyl group-containing vinyl polymer to the silyl emulsion and the acid group-containing emulsion is 80 to 60% by weight and the acid group-containing vinyl polymer is 20 to 40% by weight. Mixing is preferred. A polymer having 1 to 30% by weight of a hydrolyzable silyl group-containing monomer unit is used as the hydrolyzable silyl group-containing vinyl polymer, and an acid group-containing monomer unit is used as the acid group-containing vinyl polymer. When using a polymer having 1 to 10% by weight, the mixing ratio of the above polymer is particularly preferable. 20% by weight of acid-containing vinyl polymer
If it is less than 40% by weight, the crosslinking reaction for curing tends to be insufficient. On the other hand, if it exceeds 40% by weight, the ratio of the hydrolyzable silyl group-containing vinyl polymer becomes relatively low. The mechanical strength of the membrane is reduced.

The curable emulsion composition obtained by the production method of the present invention is first formed when the hydrolyzable silyl group-containing vinyl polymer particles and the acidic group-containing vinyl polymer particles which are separately present in the emulsion form a film. It has a characteristic that the acid group promotes the curing reaction by the silyl group upon contact, and therefore, as is clear from the examples described later, a stable emulsion state can be obtained even when left at a temperature of 60 ° C. for 2 months. It maintains and has excellent curing performance. On the other hand, a polymer having both a hydrolyzable silyl group and an acidic group cannot obtain the excellent effect as achieved by the present invention. That is, as specifically shown in Comparative Example 3, an aqueous emulsion of a polymer having both a hydrolyzable silyl group and an acidic group is easily hydrolyzed during storage, and after a while after production, a good curing property is obtained. No coating film can be obtained.

When the curable emulsion composition is used for various purposes, a curing catalyst may be blended before use if necessary, and an inorganic acid may be added to adjust the pH of the emulsion to 1 to 5,
Preferably, if adjusted to about 3 to 5, a film having more excellent mechanical strength can be obtained. Examples of the curing catalyst include isopropyltriisostearoyl titanate, organic titanate compounds such as isopropyltri (dioctylpyrophosphate) titanate, tin dioctylate, dibutyltin dilaurate, organotin compounds such as dibutyltin malate, and paratoluene sulfonic acid. To be

The curable emulsion composition obtained by the present invention is particularly suitable as a coating agent, for example, a coating material for building materials made of glass, slate, metal, wood, plastic or the like, a coating for acid rain resistance, and an antifouling agent. It can be used as a water-based paint, a water repellent for inorganic building materials, a moisture-proof coating agent for electric and electronic parts, a back coat agent for magnetic tapes, and a curing finish / water repellent for fibers.

[0030]

EXAMPLES The present invention will be described more specifically below with reference to Reference Examples, Examples and Comparative Examples. It should be noted that all “parts” in the component combination in each example are “parts by weight”. "Aqualon" used in Examples [Daiichi Kogyo Seiyaku Co., Ltd.
Is a radical-polymerizable surfactant represented by the general formula (4), and AQUALON HS05, HS10 and HS
20 is a compound in which the condensation degree n of the polyoxyethylene group in Chemical formula 4 is 5, 10 or 20, respectively. Also,
"Adeka Reap" (manufactured by Asahi Denka Kogyo Co., Ltd.) is a radically polymerizable surfactant represented by the general formula:
Adeka Leap SE-10N has a condensation degree n of the polyoxyethylene group in Chemical formula 5 of 10.

[0031]

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[0032]

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<Reference Example 1> (Production of silyl emulsion) (1) Step [1]; silyl monomer, copolymerizable monomer, radical polymerizable surfactant, oil soluble radical polymerization initiator,
A pH buffer and an aqueous medium were mixed in the amounts shown below, and after mixing with a homomixer, the mixture was further emulsified and dispersed with a homogenizer (manufactured by Gorin Co.) to obtain a pH of 8.5.
A monomer emulsion of was prepared.

Silyl-based monomer: γ-methacryloxypropyltriethoxysilane 12 parts Copolymerizable monomer: n-butyl methacrylate 45 parts n-butyl acrylate 16 parts Cyclohexyl methacrylate 10 parts Methyl methacrylate 12 parts 2-hydroxyethyl Methacrylate 5 parts Radical polymerizable surfactant: "Aqualon HS10" 0.3 parts Polymerization initiator: 2,2'-azobisisobutyronitrile 1 part pH buffer: sodium hydrogen carbonate 0.3 parts Aqueous medium: Desorption 53 parts of ionized water

(2) Step [1]; A flask equipped with a stirrer, a dropping funnel, a nitrogen gas introducing pipe, a thermometer and a condenser is charged with the following aqueous medium, and the liquid temperature is 85 ° C. while introducing nitrogen gas. The temperature was raised to. Aqueous medium: Deionized water 87 parts Surfactant: Aqualon HS10 1 part While stirring the aqueous medium in the flask at high speed, the monomer emulsion was added dropwise over 4 hours. After dropping,
After maintaining at 85 ° C. for 2 hours, it was cooled to room temperature. During the polymerization period, except that a few aggregates adhered to the inner wall of the flask,
The liquid separation or blocking did not occur, and the polymerization was performed stably. By the above-mentioned polymerization, the solid content concentration is 40% by weight,
A silyl emulsion (1) having an average particle size of polymer particles of 0.11 μm and an emulsion pH of 8.4 was obtained.
Content of grid in the emulsion (passthrough when the emulsion was filtered through a 200 mesh net)
Was 0.1% by weight or less.

<Reference Examples 2 to 5> In the same manner as in Reference Example 1, silyl emulsions (2) to (5) were produced using the monomers shown in Table 1 and surfactants.

[0037]

[Table 1]

Reference Example A (Production of Acid Group Containing Emulsion) In a flask equipped with a stirrer, a dropping funnel, a nitrogen gas introducing tube, a thermometer and a cooler, 82 parts of deionized water and a surfactant "Aqualon H" were added.
S10 "1 part was charged and the liquid temperature was adjusted to 8 while introducing nitrogen gas.
The temperature was raised to 5 ° C., and a monomer emulsion having the following composition was continuously added dropwise over 4 hours. 2 hours after dripping 85
After maintaining at 0 ° C., the mixture was cooled to room temperature and adjusted by adding deionized water so that the solid content concentration was 40%, the average particle size of the polymer particles was 0.12 μm, and the pH was 4.0. An acidic group-containing emulsion (a) was obtained. Acidic monomer: Methacrylic acid 5 parts Copolymerization monomer: n-Butyl methacrylate 36 parts n-Butyl acrylate 30 parts Cyclohexyl methacrylate 10 parts Methyl methacrylate 10 parts Divinylbenzene 0.5 parts Surfactant: "Aqualon HS10" 0 .5 parts Polymerization initiator: 2,2'-azobisisobutyronitrile 1 part Aqueous medium: Deionized water 57 parts

<Reference Example B to D> In the same manner as in Reference Example A, the acidic group-containing emulsions (B) to (D) were prepared using the monomers and surfactants shown in Table 2, and the pH was adjusted. Is 7.0
Ammonia water and deionized water were added and adjusted so that the solid content concentration was 40%.

[0040]

[Table 2]

[0041]

Examples 1 to 6 A curable emulsion composition was prepared by mixing the silyl emulsions obtained in Reference Examples 1 to 5 and the acidic group-containing emulsions obtained in Reference Examples a to d in the proportions shown in Table 3. Got The obtained curable emulsion composition was evaluated for stability as an emulsion and physical properties of coating film by the following methods. The results are shown in Table 3.
It was also described in. The water resistance of the coating film was good in each of the examples.

Solvent resistance of coating film: The curable emulsion composition was applied to release paper and left to dry at room temperature for 10 days to prepare a coating film of about 0.5 mm. The obtained dry coating film is immersed in acetone at room temperature for 24 hours, and the swelling ratio (linear expansion coefficient) and gel fraction (dry coating film weight after immersion in acetone / coating film weight before immersion) Was measured. Water resistance of coating film: The dry coating film prepared above was immersed in water at room temperature for 7 days, and then the transparency of the coating film was visually evaluated. Emulsion stability: The curable emulsion composition was placed in a sealed container and kept at 60 ° C. for 2 months, and then quantitative analysis of the amount of methanol or ethanol produced by hydrolysis of the silyl group was carried out. The decomposition rate was calculated.

[0043]

[Table 3]

[0044]

Comparative Example 1 Various physical properties of the silyl-based emulsion itself obtained in Reference Example 1 were evaluated in the same manner as the emulsion composition in Examples. The results were as follows. Solvent resistance of coating film --- Swelling rate 140%, gel fraction 86
%. Water resistance of coating film --- Poor. Hydrolysis rate of emulsion --2%.

[0045]

Comparative Example 2 To 100 parts of the silyl-based emulsion obtained in Reference Example 10 was added 10 parts of the following dibutyltin dilaurate emulsion, and the stability and the physical properties of the coating film were evaluated for the emulsion stirred for 1 hour at room temperature. . Emulsion of dibutyltin dilaurate: 10 parts of dibutyltin dilaurate, 2 parts of polyoxyethylene nonylphenyl ether and 88 parts of deionized water were mixed and emulsified with a homomixer to obtain an emulsion containing 10% by weight of dibutyltin dilaurate. The evaluation results were as follows. Solvent resistance of coating film --- Swelling rate 107%, gel fraction 99
%. The water resistance of the coating film is good. Hydrolysis rate of emulsion --- 81%.

[0046]

Comparative Example 3 An aqueous emulsion comprising a polymer having both a hydrolyzable silyl group and an acidic group was produced in the same manner as in Reference Example 1 using the following monomers and surfactants. Monomer: n-butyl methacrylate 38 parts n-butyl acrylate 20 parts cyclohexyl methacrylate 10 parts methyl methacrylate 10 parts 2-hydroxyethyl methacrylate 5 parts methacrylic acid 5 parts γ-methacryloxypropyltriethoxysilane 12 parts Surfactant: " Aqualon HS-10 "1.5 parts The obtained curable polymer emulsion was inferior in storage stability, and the physical properties of the coating film obtained using the emulsion which had been stored for 1 week at room temperature were inferior.

[0047]

Comparative Example 4 A silyl emulsion was produced in the same manner as in Reference Example 1 except that sodium polyoxyethylene nonylphenyl ether sulfate was used as the surfactant, and 100 parts by weight of this emulsion and the acidity according to Reference Example C were used. A curable emulsion composition was produced by mixing 50 parts by weight of the group-containing emulsion (C). The evaluation results of the stability of the obtained emulsion composition and the physical properties of the coating film were as follows. Solvent resistance of coating film --- Swelling rate 110%, gel fraction 98
%. Water resistance of coating film --- Poor. Hydrolysis rate of emulsion --2%.

[0048]

INDUSTRIAL APPLICABILITY The curable emulsion composition obtained by the present invention is excellent in storage stability, even though it is an aqueous emulsion of a polymer having a hydrolyzable silyl group, and is applied to a substrate. It forms a cured film with excellent curability and high crosslink density.

Claims (2)

[Claims] 1. An aqueous emulsion comprising a hydrolyzable silyl group-containing vinyl polymer is produced by the following step [1] and step [2], and this is mixed with an aqueous emulsion comprising an acidic group-containing vinyl polymer. A method for producing a curable emulsion composition, which is characterized. Step [1]: General formula Z- (AO) n-Y (In the formula, Z is a structural unit containing a radically polymerizable group, AO is an oxyalkylene group, n is an integer of 2 or more, and Y is an ion dissociable group. A vinyl monomer having a hydrolyzable silyl group, a vinyl monomer copolymerizable with the monomer, and an oil-soluble solvent in the presence of a radically polymerizable surfactant represented by A step of emulsifying and dispersing a radical polymerization initiator in an aqueous medium. Step [2]: A step of continuously or intermittently supplying the aqueous emulsion dispersion obtained in the above step [1] into an aqueous medium under stirring to polymerize the monomer in the medium. . 2. The curable emulsion composition according to claim 1, wherein the ratio of the hydrolyzable silyl group-containing vinyl polymer and the acidic group-containing vinyl polymer is 80 to 60% by weight of the former and 20 to 40% by weight of the latter. Manufacturing method.