JP5727717B2 - Method for producing polymer emulsion - Google Patents

Description

  The present invention relates to a method for producing a polymer emulsion.

  Polymer emulsions obtained by emulsion polymerization of vinyl monomers such as vinyl acetate and acrylic acid esters can be used as they are in the fields of paints, adhesives, adhesives, paper processing, fiber processing, etc. Widely used industrially. As an emulsifier in emulsion polymerization, there are anionic surfactants such as linear alkyl sulfate ester salts and linear alkylbenzene sulfonates, and nonionic surfactants such as polyoxyethylene linear alkyl ethers and polyoxyethylene alkylphenyl ethers. These are used alone or in a mixed system of anionic and nonionic surfactants.

  The performance required for emulsifiers (surfactants for emulsion polymerization) in emulsion polymerization is excellent in polymerization stability, mechanical stability and chemical stability of the resulting polymer emulsion, small emulsion particle size, and viscosity. It is low, and environmental problems do not occur.

  Patent Document 1 describes a method of emulsion polymerization of a vinyl monomer in the presence of polyoxyalkylene styrenated and / or benzylated phenyl ether sulfate. However, this technique has not yet been fully satisfactory in terms of polymerization stability and mechanical stability. Patent Document 2 discloses a surfactant composition for emulsion polymerization comprising two types of polyoxyalkylene alkyl ether sulfate salts having different CMC (critical micelle concentration). However, even with this technique, the polymerization stability, the mechanical stability of the resulting polymer emulsion, and the hot water whitening resistance of the coating film obtained using the polymer emulsion are still not fully satisfactory. Patent Document 3 discloses a surfactant composition containing one or more double bonds as a reactive group in one molecule and containing a nitrogen compound insoluble or slightly soluble in ethanol in an ionic reactive activator. Has been.

  On the other hand, from the viewpoint of economy, a non-reactive activator that does not contain a double bond as a reactive group in one molecule is known. However, the activator has good polymerization stability, and the particle size of the polymer emulsion. In addition, there is no report that the coating film has good resistance to whitening with warm water.

JP 56-161403 A Japanese Patent No. 3025763 JP 2006-75808 A

  Therefore, the present invention is sufficiently satisfactory in polymerization stability and mechanical stability of the polymer emulsion, and further has a small particle size of the polymer emulsion, and the resulting coating composition has excellent water resistance and coating gloss. An object of the present invention is to provide a production method and a coating composition.

The present invention relates to (a) a compound represented by the general formula (I),
(B) an amide compound and / or an ammonium salt having a solubility in ethanol at 25 ° C. of 5 g / 100 mL or less as an essential component;
(A) A step of subjecting a monomer having an ethylenic double bond to emulsion polymerization in the presence of a surfactant composition for emulsion polymerization containing 0.05 to 2 parts by mass of the component (b) with respect to 100 parts by mass of the component. It is a manufacturing method of the polymer emulsion containing.

Wherein R ¹ is —CH (CH ₃ ) — or —CH ₂ —,
R ² is an alkyl group having 1 to 6 carbon atoms or a hydrogen atom,
A ¹ O is an oxyalkylene group having 2 to 4 carbon atoms,
n is a number of 1 to 100 indicating the average number of added moles of the oxyalkylene group, and the n A ¹ Os may be the same or different.
m is an integer of 1 to 5,
M ¹ represents a monovalent cation. )

  According to the production method of the present invention, the polymerization stability during the production of the polymer emulsion and the mechanical stability of the polymer emulsion are sufficiently satisfied, the particle size of the polymer emulsion is small, the water resistance of the resulting coating composition, and There is an advantage of providing a polymer emulsion having a good coating gloss.

<Surfactant for emulsion polymerization>
[(A) component]
The component (a) is represented by the formula (I) as described above. In the formula (I), R ² is an alkyl group having 1 to 6 carbon atoms, such as a methyl group, an ethyl group, an n-propyl group, an n-butyl group, an n-pentyl group, and an n-hexyl group. Linear alkyl group or i-propyl group, i-butyl group, sec-butyl group, t-butyl group, i-pentyl group, sec-pentyl group, t-pentyl group, 2-methylbutyl group, 1 -Methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1-ethylbutyl group, 2-ethylbutyl group, 1,1-dimethylbutyl group, 2,2-dimethylbutyl group, 3 Branched alkyl groups such as 1,3-dimethylbutyl group and 1-ethyl-1-methylpropyl group. From the viewpoint of improving the polymerization stability during production, chain Preferred alkyl groups or branched alkyl groups of. R ² is preferably an alkyl group having 1 to 3 carbon atoms and a hydrogen atom, and more preferably a hydrogen atom, from the viewpoint of improving the polymerization stability during production.

In the formula (I), A ¹ O is an oxyalkylene group having 2 to 4 carbon atoms as described above, and examples thereof include an oxyethylene group, an oxypropylene group, and an oxybutylene group, and particularly from the viewpoint of polymerization stability. An oxyethylene group or an oxypropylene group is preferred. n is the average number of moles added of the oxyalkylene group, and is 1 to 100, preferably 3 to 50, more preferably 5 to 40, and further 8 to 30 from the viewpoint of improving the chemical stability of the polymer emulsion. preferable. The n A ¹ Os may be the same or different. When n A ¹ Os are different, any of random addition, block addition, or a combination thereof may be used. Of the n A ¹ Os, n / 2 or more A ¹ Os are preferably oxyethylene groups from the viewpoint of improving the sulfation reaction rate in obtaining the compound of formula (I), More preferably, A ¹ O is an oxyethylene group.

In the formula (I), m represents an integer of 1 to 5, and an integer of 1 to 3 is preferable and 1 or 2 is more preferable from the viewpoint of improving the polymerization stability during production of the polymer emulsion. M ¹ is a monovalent cation, for example, an alkali metal cation such as sodium or potassium; ammonium; or an amine cation such as alkanolamine. From the viewpoint of improving the water resistance of the coating film, an alkali metal cation And ammonium are preferred, and ammonium is more preferred.

  Examples of the compound represented by the formula (I) include polyoxyalkylene (alkylene having 2 to 4 carbon atoms) styrenated phenyl ether monosulfate, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) distyrenated phenyl. Ether monosulfate, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) tristyrenated phenyl ether monosulfate, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) styrenated methyl phenyl ether monosulfate, Polyoxyalkylene (alkylene having 2 to 4 carbon atoms) distyrenated methyl phenyl ether monosulfate, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) tristyrenated methyl phenyl ether monosulfate, polyoxyalkylene (alkylene) 2-4) benzylated phenyl ether monosulfate salt, polyoxyalkylene (alkylene having 2-4 carbon atoms) dibenzylated phenyl ether monosulfate salt, polyoxyalkylene (2-4 carbon atoms of alkylene) tribenzyl Phenyl ether monosulfate, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) benzylated methyl phenyl ether monosulfate, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) dibenzylated methyl phenyl ether monosulfate Salts, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) tribenzylated methylphenyl ether monosulfate, and the like. The compound represented by the formula (I) includes polyoxyalkylene (alkylene having 2 to 4 carbon atoms) distyrenated phenyl ether monosulfate, polyoxyalkylene from the viewpoint of improving the polymerization stability during production of the polymer emulsion. (Alkylene 2 to 4 carbon atoms) Distyrenated methyl phenyl ether monosulfate ester salt and polyoxyalkylene (alkylene 2 to 4 carbon atoms) benzylated phenyl ether monosulfate salt are preferable.

  The compound represented by the formula (I) can be produced by a known method. For example, styrene or benzyl chloride is added to phenol or an alkylphenol having 1 to 6 carbon atoms by Friedel-Crafts reaction using aluminum chloride, zinc chloride or activated clay as a catalyst. Further, the alkylene oxide having 2 to 4 carbon atoms is added to the hydroxyl group of this addition product in the presence of a non-catalyst, a base catalyst or an acid catalyst in one step or in multiple steps under normal pressure or pressure, and sulfation is performed. It can be produced by esterifying with an agent and neutralizing with a basic substance if necessary. Examples of the sulfating agent include sulfamic acid, sulfuric acid, anhydrous sulfuric acid, fuming sulfuric acid, chlorosulfonic acid and the like. Among them, from the viewpoint of improving the sulfation efficiency when obtaining the compound of formula (I), and benzene ring From the viewpoint of preventing sulfonation of sulfamic acid, sulfamic acid is preferable.

[Component (b)]
As described above, the component (b) has a solubility in ethanol at 25 ° C. of 5 g / 100 mL or less (the amount dissolved in 100 mL of ethanol is 5 g or less) and a solubility in ethanol at 25 ° C. of 5 g / 100 mL. It is an ammonium salt below (the amount dissolved in 100 mL of ethanol is 5 g or less). Examples of these amide compounds and / or ammonium salts include urea, sulfamate, ammonium chloride, ammonium sulfate, and ammonium sulfite. Among these amide compounds and ammonium salts, urea, sulfamate, and ammonium sulfate are preferable from the viewpoint of the effect of improving the polymerization stability during production of the polymer emulsion.

  In the surfactant composition for emulsion polymerization, the component (b) is 0.05 to 2 parts by weight, preferably 0.05 to 1.0 parts by weight, more preferably 100 parts by weight of the component (a). 0.05-0.5 mass part is contained. If the content of component (b) is 0.05 parts by mass or more, the effect of improving polymerization stability during emulsion polymerization is high, and if it is 2 parts by mass or less, the water resistance of the polymer emulsion coating film is good. become. In addition, in the surfactant composition for emulsion polymerization, if an amide compound or ammonium salt having a solubility in ethanol at 25 ° C. of 5 g / 100 mL or less is contained, the polymerization stability during emulsion polymerization in the presence of the composition is increased. The water resistance of the coating film coated with the obtained polymer emulsion is improved.

  The component (b) can be included in the surfactant composition for emulsion polymerization by an arbitrary method, and at the time of producing the surfactant composition for emulsion polymerization, the system is independently and simultaneously with the component (a). Or it can mix and add beforehand. Moreover, it can be added also at the time of manufacture of (a) component, and the addition time may be any before manufacture of (a) component, during manufacture of (a) component, and after manufacture of (a) component. From the viewpoint of reducing the influence on the production of the component (a), it is preferably added after the production of the component (a). Moreover, when (b) component is used also as a raw material of (a) component, (b) component more than a required amount may be previously contained in the surfactant composition for emulsion polymerization.

[Other ingredients]
The surfactant composition for emulsion polymerization used in the production method of the present invention can further contain other components as long as the effects of the present invention are not impaired. Examples of other components include nonionic surfactants such as alcohol ethoxylates, alkylphenol ethoxylates, alkyl polyglycosides, and alkanolamides; alkylbenzene sulfonates, alkyl sulfates, alkyl ether sulfates, α-olefin sulfonates, fatty acid soaps , Anionic surfactants such as alkyl ether carboxylates, water and the like.

<Monomer having an ethylenic double bond>
Specific examples of the monomer having an ethylenic double bond used in the production method of the present invention include aromatic vinyl monomers such as styrene, α-methylstyrene, and chlorostyrene; methyl acrylate, ethyl acrylate, butyl acrylate, etc. Acrylic acid esters; methacrylic acid esters such as methyl methacrylate and ethyl methacrylate; vinyl monomers having a carboxyl group such as acrylic acid and methacrylic acid; vinyl halides and halogens such as vinyl chloride, vinyl bromide, vinylidene chloride Vinylidene chlorides; vinyl esters such as vinyl acetate and vinyl propionate; nitriles such as acrylonitrile and methacrylonitrile; conjugated dienes such as butadiene and isoprene. These monomers may be used independently or may use 2 or more types together. The monomer having an ethylenic double bond is preferably a vinyl monomer from the viewpoint of increasing the reactivity of the monomer.

<Amount of surfactant composition for emulsion polymerization>
In the method for producing a polymer emulsion of the present invention, the surfactant composition for emulsion polymerization may comprise (a) component and (b) with respect to 100 parts by mass of the monomer from the viewpoint of improving polymerization stability during production of the polymer emulsion. ) The total amount of components is preferably from 0.1 to 20 parts by mass, more preferably from 0.1 to 10 parts by mass, and even more preferably from 0.5 to 5 parts by mass.

<Polymerization initiator>
In the method for producing a polymer emulsion of the present invention, a polymerization initiator can be used during emulsion polymerization. Any polymerization initiator can be used as long as it is used in ordinary emulsion polymerization. Examples thereof include persulfates such as potassium persulfate and ammonium persulfate, hydrogen peroxide, t-butyl hydroperoxide, and benzoyl peroxide. Examples include organic peroxides such as oxide and cumene hydroperoxide, azo initiators such as azobisdiisobutyronitrile, 2,2-azobis (2-amidinopropane) dihydrochloride, etc. Persulfate is preferred because of its superiority. Furthermore, as the polymerization initiator, a redox initiator in which a peroxide and a reducing agent such as sodium sulfite, Rongalite, and ascorbic acid are combined can also be used.

<Amount of monomer>
In the method for producing a polymer emulsion of the present invention, the emulsion polymerization conditions are not particularly limited, and the amount of the monomer used is from the viewpoint of improving the coexistence of the viscosity of the emulsion, that is, handleability and economy, with respect to the entire system. 20-90 mass% is preferable, and 40-80 mass% is more preferable. Moreover, as a monomer addition method, any method such as a monomer dropping method, a monomer batch charging method, a pre-emulsion method and the like can be used, and the pre-emulsion method is preferable from the viewpoint of improving the polymerization stability during the production of the polymer emulsion. In the pre-emulsion method, the pre-emulsion dropping time is preferably 1 to 8 hours, and the aging time is preferably 1 to 5 hours. The polymerization temperature is adjusted by the decomposition temperature of the initiator, but is preferably 50 to 90 ° C., and preferably 70 to 85 ° C. in the case of persulfate from the viewpoint of improving the polymerization stability during the production of the polymer emulsion.

<Polymer emulsion>
The polymer emulsion of the present invention is obtained by the method for producing a polymer emulsion of the present invention.

  The solid content of the polymer emulsion of the present invention is preferably 20 to 70% by mass, more preferably 40 to 60% by mass, from the viewpoint of improving the mixing property between the polymer emulsion and the pigment dispersion.

<Coating composition>
The coating composition of the present invention contains the polymer emulsion obtained by the production method of the present invention as described above. The volume average particle size of the polymer emulsion is preferably from 30 to 500 nm, more preferably from 100 to 300 nm, and more preferably from 120 to 170 nm, from the viewpoint of improving the water resistance and coating gloss of the coating composition obtained using the polymer emulsion. Is more preferable. The volume average particle diameter of the polymer emulsion is a value measured by the method shown in Examples described later.

  The coating composition of the present invention can further contain a pigment, and if necessary, water, a viscosity control agent, an antifoaming agent, an antioxidant, an ultraviolet absorber, and the like. Examples of pigments include extender pigments such as talc, kaolin, calcium carbonate, and barium sulfate, colored pigments such as bengara, carbon black, ultramarine, and yellow iron oxide, white pigments such as titanium dioxide and zinc oxide, titanium mica, and bismuth oxychloride. Inorganic pigments such as pearl pigments, dyes as organic synthetic dyes, organic pigments, and the like. These pigments may be used alone or in combination of two or more.

  The content of the polymer emulsion in the coating composition of the present invention is preferably 5 to 90 from the viewpoint of improving the coating concealing property and the substrate adhesion in terms of solid content relative to the solid content in the coating composition. It is 10 mass%, More preferably, it is 10-85 mass%, More preferably, it is 15-80 mass%.

When the coating composition of the present invention contains a pigment, the content of the pigment in the coating composition is based on the total solid content in the coating composition from the viewpoint of improving the concealability of the coating film and the adhesion to the substrate. It is preferably 5 to 95% by mass, more preferably 20 to 80% by mass, and still more preferably 30 to 70% by mass in terms of solid matter (PWC).

PWC = solid content of pigment in coating composition / (total solid content in coating composition) × 100

  The pigment is preferably blended with the polymer emulsion in the form of an aqueous dispersion, and the pigment aqueous dispersion can be prepared by a known method. For example, an aqueous pigment dispersion can be obtained by dispersing a pigment alone or a mixture, water and, if necessary, a dispersion aid using a dispersing device. A homomixer, a sand mill, a ball mill, a roll mill, a paint shaker, or the like can be used as a dispersion apparatus used for producing the pigment aqueous dispersion. If necessary, an antifoaming agent, preservative, etc. may be added to the pigment aqueous dispersion.

The following (a-1) to (a-5) were produced as the component (a) by the method shown below.
<(A) component>
(A-1): polyoxyethylene (20) distyrenated phenyl ether monosulfate ammonium salt (a-2): polyoxyethylene (13) distyrenated phenyl ether monosulfate ammonium salt (a-3): polyoxy Propylene (3) Polyoxyethylene (10) Distyrenated phenyl ether monosulfate ammonium salt (a-4): Polyoxyethylene (7) Distyrenated methyl phenyl ether monosulfate ammonium salt (a-5): Polyoxyethylene (10) Benzylated phenyl ether monosulfate ammonium salt

<Production Example 1: Production of (a′-1)>
608 g (2 mol) of commercially available distyrenated phenol (manufactured by Kawaguchi Chemical Industry Co., Ltd.) and 0.56 g (0.01 mol) of potassium hydroxide were charged into an autoclave equipped with a stirrer, a temperature control device and an automatic introduction device. And dehydration at 1.3 kPa for 30 minutes. After dehydration, nitrogen substitution was carried out, and after raising the temperature to 145 ° C., 1760 g (40 mol) of ethylene oxide (EO) was charged. After an addition reaction at 145 ° C. and aging at that temperature for 1 hour, the mixture was cooled to 80 ° C., and unreacted EO was removed from the reaction system at 4.0 kPa. After removal of unreacted EO, the catalyst potassium hydroxide was removed using an adsorbent to obtain polyoxyethylene (20) distyrenated phenol having an average addition mole number of ethylene oxide of 20 moles.

  Charge 592.0 g (0.5 mol) of this polyoxyethylene (20) distyrenated phenol to a reactor equipped with a stirrer, a temperature controller and an automatic introduction device, and dehydrate at 110 ° C. and 1.3 kPa for 30 minutes. went. After cooling to 70 to 80 ° C., 46.1 g (0.475 mol) of sulfamic acid was charged, the temperature was raised to 110 ° C., the mixture was reacted for 3 hours, and polyoxyethylene (20) distyrenated phenyl ether monosulfate ammonium salt ( a′-1) was obtained.

<Production Example 2: Production of (a′-2)>
608 g (2 mol) of commercially available distyrenated phenol (manufactured by Kawaguchi Chemical Industry Co., Ltd.) and 0.56 g (0.01 mol) of potassium hydroxide were charged into an autoclave equipped with a stirrer, a temperature control device and an automatic introduction device. And dehydration at 1.3 kPa for 30 minutes. After dehydration, nitrogen substitution was carried out, and after raising the temperature to 145 ° C., 1144 g (26 mol) of ethylene oxide was charged. After an addition reaction at 145 ° C. and aging at that temperature for 1 hour, the mixture was cooled to 80 ° C., and unreacted EO was removed from the reaction system at 4.0 kPa. After removal of unreacted EO, the catalyst potassium hydroxide was removed using an adsorbent to obtain polyoxyethylene (13) distyrenated phenol having an average addition mole number of ethylene oxide of 13 moles.

  438.0 g (0.5 mol) of this polyoxyethylene (13) distyrenated phenol was charged into a reactor equipped with a stirrer, a temperature controller and an automatic introduction device, and dehydrated at 110 ° C. and 1.3 kPa for 30 minutes. went. After cooling to 70 to 80 ° C., 46.1 g (0.475 mol) of sulfamic acid was charged, the temperature was raised to 110 ° C., the reaction was carried out for 3 hours, and polyoxyethylene (13) distyrenated phenyl ether monosulfate ammonium salt ( a′-2) was obtained.

<Production Example 3: Production of (a′-3)>
608 g (2 mol) of commercially available distyrenated phenol (manufactured by Kawaguchi Chemical Industry Co., Ltd.) and 0.56 g (0.01 mol) of potassium hydroxide were charged into an autoclave equipped with a stirrer, a temperature control device and an automatic introduction device. And dehydration at 1.3 kPa for 30 minutes. After dehydration, nitrogen substitution was performed, the temperature was raised to 120 ° C., and 348 g (6 mol) of propylene oxide was charged. After an addition reaction and aging at 120 ° C., dehydration and nitrogen substitution were carried out, and after raising the temperature to 145 ° C., 880 g (20 mol) of ethylene oxide was charged. After an addition reaction at 145 ° C. and aging at that temperature for 1 hour, the mixture was cooled to 80 ° C., and unreacted EO was removed from the reaction system at 4.0 kPa. After removal of unreacted EO, potassium hydroxide as a catalyst is removed using an adsorbent, and polyoxypropylene (3) poly having an average added mole number of propylene oxide of 3 moles and an average added mole number of ethylene oxide of 10 moles. Oxyethylene (10) distyrenated phenol was obtained.

  459.0 g (0.5 mol) of this polyoxypropylene (3) polyoxyethylene (10) distyrenated phenol was charged into a reactor equipped with a stirrer, a temperature controller and an automatic introduction device, and 110 ° C., 1.3 kPa. For 30 minutes. After cooling to 70 to 80 ° C., 46.1 g (0.475 mol) of sulfamic acid was charged, the temperature was raised to 110 ° C. and reacted for 3 hours to obtain polyoxypropylene (3) polyoxyethylene (10) distyrenated phenyl ether. Monosulfuric acid ester ammonium salt (a′-3) was obtained.

<Production Example 4: Production of (a′-4)>
Commercially available polyoxyethylene (7) distyrenated methylphenol (Nippon Emulsifier Co., Ltd., New Coal 707) 313.0 g (0.5 mol) was charged into a reactor equipped with a stirrer, a temperature controller, and an automatic introduction device. Dehydration was performed at 1.3 ° C. for 30 minutes. After cooling to 70-80 ° C., 46.1 g (0.475 mol) of sulfamic acid was charged, heated to 110 ° C., reacted for 3 hours, and polyoxyethylene (7) distyrenated phenyl ether monosulfate ammonium salt ( a′-4) was obtained.

<Production Example 5: Production of (a'-5)>
592 g (2 mol) of commercially available tribenzylated phenol (manufactured by Kawaguchi Chemical Co., Ltd.) and 0.56 g (0.01 mol) of potassium hydroxide were charged into an autoclave equipped with a stirrer, a temperature control device and an automatic introduction device, and 110 ° C. And dehydration at 1.3 kPa for 30 minutes. After dehydration, nitrogen substitution was carried out, and after raising the temperature to 145 ° C., 880 g (20 mol) of ethylene oxide was charged. After addition reaction and aging at 145 ° C., the mixture was cooled to 80 ° C., and unreacted EO was removed from the reaction system at 4.0 kPa. After removal of unreacted EO, the catalyst potassium hydroxide was removed using an adsorbent to obtain polyoxyethylene (10) tribenzylated phenol having an average addition mole number of ethylene oxide of 10 moles.

  368.0 g (0.5 mol) of this polyoxyethylene (10) tribenzylated phenol was charged into a reactor equipped with a stirrer, a temperature controller and an automatic introduction device, and dehydrated at 110 ° C. and 1.3 kPa for 30 minutes. went. After cooling to 70 to 80 ° C., 46.1 g (0.475 mol) of sulfamic acid was charged, the temperature was raised to 110 ° C., and the mixture was allowed to react for 3 hours to give polyoxyethylene (10) tribenzylated phenyl ether sulfate ammonium salt (a '-5) was obtained.

  To 100 parts by mass of each of the compounds (a′-1) to (a′-5), 300 mL of ethanol was added and dissolved by stirring at room temperature (25 ° C.). This solution was filtered through a 0.2 μm membrane filter.

  The filtrate was topped under reduced pressure to remove ethanol, and a sample containing no ethanol-insoluble matter was obtained. Each of the compounds obtained from (a′-1), (a′-2), (a′-3), (a′-4) and (a′-5) is converted into (a-1), (a -2), (a-3), (a-4) and (a-5). Moreover, when the residue (ethanol insoluble matter amount) on the filter paper was measured, the ethanol insoluble matter was less than 0.05% by mass.

In the examples, “%” means “% by mass” unless otherwise specified.
[Examples 1-12 and Comparative Examples 1-12]
(A) The above components (a-1) to (a-5), the following (b) components and comparative products are used as components, blended in the proportions shown in Table 2, and used in the present invention and the comparative production method. A surfactant composition for polymerization was prepared. In the presence of the obtained surfactant composition for emulsion polymerization, emulsion polymerization was carried out by the following method to obtain a polymer emulsion. The performance of the obtained polymer emulsion was evaluated by the following method. Moreover, the coating composition was created by the following method using the obtained polymer emulsion, and gloss was measured by the following method. These results are shown in Table 2.

<(B) component>
(B-1): Sulfamic acid ammonium salt (Wako Pure Chemical Industries, Ltd. reagent)
(B-2): Urea (Reagent manufactured by Wako Pure Chemical Industries, Ltd.)
(B-3): Ammonium sulfate (Wako Pure Chemical Industries, Ltd. reagent)

<Other ingredients>
Comparative product (c-1) Surfactant composition described in Example 1 of Japanese Patent No. 3025763. That is, (a-1): C ₈ H ₁₇ O (CH ₂ CH ₂ O) ₁₈ SO ₃ Na (CMC 0.029 mol / L) and (b-1): C ₁₂ H ₂₅ O (CH ₂ CH ₂ O) ) ₁₈ SO ₃ Na (CMC 0.0046 mol / L) in a (a) / (b) molar ratio of 20/80.
(D-1) A surfactant composition of Invention 5 described in Examples of JP-A-2006-75808. That is, surfactant (2-e) (100 parts by mass) represented by the following structure, urea (nitrogen compound 1, 0.1 part by mass) and ammonium sulfamate (nitrogen compound 2, 0.05 part by mass) Containing surfactant composition.

Surfactant (2-e)

<Emulsion polymerization method>
In a 1 L flask equipped with a stirrer and a raw material inlet, 112.5 g of ion-exchanged water, 0.36 g of potassium persulfate as a polymerization initiator, a surfactant composition for emulsion polymerization used in the production method of the present invention, or comparative emulsion polymerization A monomer mixture of 110.8 g of butyl acrylate, 110.8 g of methyl methacrylate and 3.4 g of acrylic acid was dropped over about 5 minutes while mixing 3.6 g of the surfactant composition for stirring and stirring at 500 r / min. And stirred for 30 minutes to obtain an emulsion dropping liquid.

  Next, in a 1 L separable flask equipped with a stirrer, a reflux condenser, and a raw material inlet, 162.5 g of ion-exchanged water, 0.09 g of potassium persulfate as a polymerization initiator, and emulsion polymerization used in the production method of the present invention A surfactant composition or a comparative surfactant composition for emulsion polymerization (0.90 g) and 5% by mass (17.1 g) of the emulsion drop solution were charged, heated to 80 ° C., and polymerized for the first stage for 30 minutes. Was done. Thereafter, the remaining emulsion dropping solution was added dropwise over 3 hours, and after completion of the addition, it was further aged for 1 hour. The obtained polymer emulsion was cooled to 30 ° C. or lower and filtered through a 200 mesh stainless steel wire mesh to collect aggregates in the polymer emulsion. Aggregates adhered to the flask and the stirring blade were also collected. In addition, solid content concentration of the polymer emulsion of an Example and a comparative example was adjusted so that it might become 44.8-45.4 mass%.

<How to make paint>
A 250 mL plastic container was charged with 50 g of 1 mm diameter and 2 mm diameter glass beads, 150 g of titanium dioxide, 3.75 g of sodium polyacrylate (40% by mass) (poise 530, manufactured by Kao Corporation), and 62 g of ion-exchanged water, and paint. The mixture was stirred for 3 hours with a shaker to prepare a pigment aqueous dispersion having a pigment solid content of 70% by mass.

Next, 7.1 g of the pigment aqueous dispersion, 11.1 g of each polymer emulsion, and 1.8 g of ion-exchanged water are weighed and mixed uniformly in the flask, and the finished paint solid content is 50% by mass, based on the solid content in the paint composition. A paint having a solid content of polymer emulsion of 50% by mass and a PWC of 50% by mass was obtained. PWC is a value calculated by the following equation.
PWC = solid content of pigment in coating composition / (total solid content in coating composition) × 100

<Performance evaluation method>
(1) Polymerization stability of polymer emulsion The recovered aggregate was washed with water, dried at 26.6 kPa and 105 ° C. for 2 hours, and weighed to determine the amount of aggregate. Polymerization stability was expressed in terms of mass% of aggregates based on the total amount of monomers used. The smaller the mass% of the aggregate, the better the polymerization stability.

(2) Volume average particle diameter of polymer emulsion particles The obtained polymer emulsion was neutralized with 25% aqueous ammonia to a pH of 8-9. The volume average particle diameter of the polymer emulsion particles after neutralization was measured using a dynamic light scattering particle size measuring apparatus N4 Plus manufactured by Beckman Coulter.

(3) Mechanical stability of polymer emulsion 50 g of the neutralized polymer emulsion was weighed, and the rotor was rotated for 5 minutes under the conditions of a load of 98 N and 1000 r / min using a Maron mechanical stability tester. Aggregates were formed. This agglomerate was filtered through a 200 mesh stainless steel wire mesh, and the filtered product was washed with water and dried at 26.6 kPa and 105 ° C. for 2 hours. The obtained agglomerates were weighed, and the amount of agglomerates relative to the polymer was expressed in mass%. It shows that it is excellent in mechanical stability, so that the amount of aggregates is small.

(4) Warm water whitening resistance of polymer emulsion coating film The neutralized polymer emulsion was coated on a transparent acrylic plate using an applicator so that the dry film thickness was 50 μm, and 100 ° C. with a hot air dryer. Dried for 10 minutes. After this acrylic plate was immersed in warm water of 60 ° C. for 48 hours, the haze value of the coating film was measured using a haze meter. It shows that warm water whitening resistance is so favorable that a haze value is small.

(5) Paint film gloss of paint 8 was coated on a polypropylene film, and after coating, it was dried overnight at room temperature to obtain a coating film for evaluation. The surface gloss of the coating film was measured with a gloss meter (GM-60, manufactured by Minolta Co., Ltd.) at an incident angle of 60 °. It shows that it is excellent in coating-film gloss, so that the value of surface gloss is high.

  As shown in Table 2, according to the method for producing a polymer emulsion of the present invention, the coating composition can be satisfactorily satisfied in the polymerization stability and the mechanical stability of the polymer emulsion, and the particle size of the polymer emulsion is small. It was confirmed that a polymer emulsion having excellent water resistance and gloss of the coating film was obtained.

[Examples 13 to 24 and Comparative Examples 13 to 24]
A surfactant composition for emulsion polymerization shown in Table 3 and a comparative surfactant composition for emulsion polymerization were used, except that 109.7 g of butyl acrylate, 109.7 g of styrene, and 5.6 g of acrylic acid were used as monomers. The emulsion polymerization was carried out under the same conditions as in Examples 1 to 12 and Comparative Examples 1 to 12, and the performance was similarly evaluated. Also, an aqueous pigment dispersion was prepared in the same manner as in Examples 1-12 and Comparative Examples 1-12, and 4.76 g of the aqueous pigment dispersion, 11.1 g of each polymer emulsion, and 0.8 g of ion-exchanged water were weighed in a flask. The resulting mixture was uniformly mixed to obtain a paint having a finished paint solid content of 50% by mass, a solid content of the polymer emulsion of 60% by mass, and a PWC of 40% by mass, based on the solid content in the coating composition. This paint was applied on a polypropylene film in the same manner as in Examples 1 to 12 and Comparative Examples 1 to 12, and the surface gloss of the coating film was measured. The results are shown in Table 3.

  As shown in Table 3, according to the method for producing a polymer emulsion of the present invention, the coating composition can be satisfactorily satisfied in the polymerization stability and the mechanical stability of the polymer emulsion, and the particle size of the polymer emulsion is small. It was confirmed that a polymer emulsion having excellent water resistance and gloss of the coating film was obtained.

  The production method of the present invention can also be applied to the use for preparing a polymer emulsion for paint.

Claims (6)

(A) a compound represented by the general formula (I);
(B) an amide compound and / or an ammonium salt having a solubility in ethanol at 25 ° C. of 5 g / 100 mL or less as an essential component;
The amide compound and / or ammonium salt of component (b) is one or more selected from urea, ammonium sulfamate and ammonium sulfate,
(A) A step of subjecting a monomer having an ethylenic double bond to emulsion polymerization in the presence of a surfactant composition for emulsion polymerization containing 0.05 to 2 parts by mass of the component (b) with respect to 100 parts by mass of the component. A method for producing a polymer emulsion.
Wherein R ¹ is —CH (CH ₃ ) — or —CH ₂ —,
R ² is an alkyl group having 1 to 6 carbon atoms or a hydrogen atom,
A ¹ O is an oxyalkylene group having 2 to 4 carbon atoms,
n is a number of 1 to 100 indicating the average number of added moles of the oxyalkylene group, and the n A ¹ Os may be the same or different.
m is an integer of 1 to 5,
M ¹ represents a monovalent cation. ) The method for producing a polymer emulsion according to claim 1 , wherein the amide compound and / or ammonium salt of component (b) is ammonium sulfamate. In formula (I), R < ² > is a C1-C3 alkyl group or a hydrogen atom, The manufacturing method of the polymer emulsion of Claim 1 or 2 . The compound represented by the formula (I) is a polyoxyalkylene (alkylene having 2 to 4 carbon atoms) distyrenated phenyl ether monosulfate, polyoxyalkylene (alkylene having 2 to 4 carbon atoms) distyrenated methyl phenyl ether mono The method for producing a polymer emulsion according to any one of claims 1 to 3 , wherein the polymer emulsion is selected from the group consisting of a sulfate ester salt and a polyoxyalkylene (alkylene having 2 to 4 carbon atoms) benzylated phenyl ether monosulfate salt. The method for producing a polymer emulsion according to any one of claims 1 to 4 , wherein the total amount of the component (a) and the component (b) is 0.1 to 20 parts by mass with respect to 100 parts by mass of the total monomers. The coating composition containing the polymer emulsion obtained by the method in any one of Claims 1-5 .