JPH0124164B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a vinyl polymer emulsion. More specifically, the present invention relates to a method for producing a vinyl polymer emulsion having low foaming properties and superior polymerization stability. Conventionally, as a manufacturing method for low foaming emulsion,
A method of emulsion (co)polymerizing vinyl monomers using polyoxyalkylene styrenated phenyl ether is known. The vinyl polymer emulsion obtained by this method has low foaming properties, but
Polymerization stability is not always satisfactory. The present inventors have arrived at the present invention as a result of intensive studies on a method for producing a low-foaming vinyl polymer emulsion with further improved polymerization stability. That is, the present invention involves converting a vinyl monomer into a polyoxyalkylene styrenated or/and benzylated phenyl ether sulfate salt (A) and, if necessary, other anionic surfactants, nonionic surfactants, and water-soluble This is a method for producing a vinyl polymer emulsion, which is characterized by carrying out emulsion polymerization in the presence of at least one compound (B) selected from the group consisting of oligomers. The polyoxyalkylene styrenated or/and benzylated phenyl ether sulfate salt (A) used in the present invention has the general formula (In the formula, m and m ¹ are 0 or an integer of 1 to 3,
m+m ¹ =1 to 3, A is an alkylene group having 2 to 3 carbon atoms, n is an integer of 1 to 100, and M is a cation. ) is used. Such sulfate ester salt (A) has the general formula
Polyoxyalkylene styrenated phenyl ether sulfate salt represented by (1) (A ₁ ), polyoxyalkylene benzylated phenyl ether sulfate salt represented by general formula (2) (A ₂ ), general formula (3) Examples include polyoxyalkylene styrenated benzylated phenyl ether sulfate sulfate salts (A ₃ ) represented by ), and mixtures of two or more thereof. (In the formula, m ¹ and m ² are integers of 1 to 3, m ³ and m ⁴ are 1
or 2, m ³ + m ⁴ = 2-3, A ¹ , A ² , A ³ are alkylene groups with 2-3 carbon atoms, n ¹ , n ² , n ³ are 1-3
In the general formulas ( ¹ ), ( ² ), ( ³ ), m ¹ , m ² , (m ³ +
m ⁴ ) is an integer from 1 to 3, and if it is less than 1 or more than 3, the polymerization stability will be extremely poor. ^A1 ,
A ² and A ³ are alkylene groups having 2 to 3 carbon atoms,
Examples include ethylene group and propylene group. An alkylene group forms an oxyalkylene group together with an oxygen atom, and when two or more oxyalkylene groups exist, an oxyethylene group alone or a combination of oxyethylene and oxypropylene groups (combined in random or block form) ) can be given. n ¹ , n ² , n ³ are integers from 1 to 100,
Preferably it is an integer from 10 to 80. n ¹ , n ² , n ³ are 1
When it is less than 100 or more than 100, polymerization stability deteriorates. Also, if water resistance is required, n ¹ ,
It is preferable to make n ² and n ³ small. ^M1 , ^M2 , ^M3
is an alkali metal, ammonium or amine cation. Alkali metals include sodium and potassium. Amine cations include lower alkylamines (methylamine, ethylamine, isopropylamine, dimethylamine,
Examples include cations of amines such as trimethylamine, etc.), alkanolamines (monoethanolamine, triethanolamine, etc.), and morpholine. Examples of the compound represented by general formula (1) include compounds having the following chemical formula. Examples of the compound represented by general formula (2) include compounds having the following chemical formula. Among (A), preferred are compounds represented by general formulas (1) and (2). In the present invention, vinyl monomers that are commonly used in emulsion polymerization can be used.
Examples of such monomers include lipophilic vinyl monomers, weakly hydrophilic vinyl monomers, and combinations thereof. Lipophilic vinyl monomers include monoethylene monomers (ethylene, etc.), diene monomers (butadiene, chloroprene, etc.), aromatic monomers (styrenes, such as styrene, α-alkylstyrene, etc.). ), halogen-containing vinyl monomers (vinyl chloride, vinylidene chloride, etc.), higher alcohols (linear or branched natural or synthetic alcohols with 5 or more carbon atoms, such as 2-ethylhexyl alcohol, decyl alcohol, lauryl alcohol, myristyl alcohol, cetyl alcohol,
Examples include (meth)acrylate monomers from stearyl alcohol, oxo alcohol, Ziegler alcohol, paraffin oxidation alcohol, etc. Among these, preferred are:
These are (meth)acrylate monomers and aromatic monomers derived from higher alcohols. Weakly hydrophilic vinyl monomers include vinyl ester monomers (vinyl acetate, vinyl propionate, etc.), lower alcohols (linear or branched alcohols having 1 to 4 carbon atoms, such as methyl alcohol,
Examples include (meth)acrylate monomers (ethyl alcohol, butyl alcohol, etc.), and nitrile monomers (acrylonitrile, etc.). Among these, preferred are (meth)acrylate monomers derived from lower alcohols and vinyl ester monomers. Moreover, a hydrophilic monomer can also be used as part of the monomers if necessary. Such hydrophilic monomers include monomers containing carboxy (or its salt form) [(meth)acrylic acid, itaconic acid, maleic acid, and their sodium salts, etc.];
Sulfonic group-containing monomers [vinylsulfonic acid, (meth)acryloyloxyaminodimethylethanesulfonic acid, etc.], carbamoyl group-containing monomers [(meth)acrylamide, etc.], and hydroxyl group-containing monomers [hydroxyethyl (meth) ) acrylate, etc.]. Among these, monomers containing carboxy (or a salt group thereof) are preferred. Amount used is typically 10 based on total monomer weight
% or less, preferably 5% or less. Among vinyl monomers, weakly hydrophilic monomers and lipophilic monomers are preferred, and weakly hydrophilic monomers are particularly preferred. Vinyl monomers can be used in combination. When used in combination, combinations of weakly hydrophilic monomers, combinations of weakly hydrophilic monomers and lipophilic monomers, combinations of lipophilic monomers, and combinations of these combinations and hydrophilic monomers are used. can give. Among these, combinations of weakly hydrophilic monomers and combinations of weakly hydrophilic monomers and lipophilic monomers are preferred. Examples of the compound (B) selected from the group consisting of an anionic surfactant, a nonionic surfactant, and a water-soluble oligomer to be used in combination with (A) if necessary in the present invention include the following compounds. Examples of anionic surfactants include the compounds described on pages 31 to 58 of "Introduction to New Surfactants" (written by Takehiko Fujimoto, published December 1, 1970, published by Sanyo Chemical Industries, Ltd.). Among these, preferred are higher alkyl ether sulfate salts (polyoxyethylene lauryl ether sulfate salts, etc.),
Alkyl allyl ether sulfate salts (such as polyoxyethylene nonyl phenyl ether sulfate salts), alkylbenzene sulfonates (such as dodecylbenzene sulfonate), alkylnaphthalene sulfonates (such as butylnaphthalene sulfonate), and dialkyl sulfonate salts (such as butylnaphthalene sulfonate). Succinates (such as dioctyl sulfosuccinate). Examples of nonionic surfactants include the compounds described on pages 89 to 124 of the above-mentioned "Introduction to New Surfactants." Among these, preferred are higher alcohol ethylene oxide adducts (polyoxyethylene lauryl ether, etc.), alkylphenol ethylene oxide adducts (polyoxyethylene nonyl phenyl ether, etc.), and polyethylene glycol fatty acid esters (polyethylene glycol lauryl ether, etc.). polypropylene glycol ethylene oxide adducts (polyoxypropylene polyoxyethylene block copolymers, etc.) and polyhydric alcohol fatty acid ester ethylene oxide adducts (polyoxyethylene sorbitan fatty acid esters, etc.)
It is. As a water-soluble oligomer, the molecular weight is usually 1000~
10,000 water-soluble low molecular weight polymers.
Specifically, polycarboxylic acids (polyacrylic acid, polyitaconic acid, etc.) and their alkali metal salts (sodium salt, potassium salt, etc.), styrene-maleic acid copolymers and their alkali metal salts (sodium salt, potassium salt, etc.) Isobutylene-maleic acid copolymer and its alkali metal salts (sodium salt, potassium salt, etc.). Among (B), preferred are nonionic surfactants and water-soluble oligomers, especially the former. In the present invention, (A) is usually used in an amount of 1 to 10 parts by weight (hereinafter, parts and percentages are based on weight), preferably 2 to 5 parts by weight, per 100 parts by weight of the vinyl monomer. Can be done. In addition, (A) and at least one compound (B) selected from the group consisting of other anionic surfactants, nonionic surfactants, and water-soluble oligomers can be used in combination; in this case, ( A) and (B) are vinyl monomers 100%
It is carried out using usually 1 to 10 parts, preferably 2 to 5 parts. The amount of (A) in the total amount of (A) and (B) is usually 30% or more, preferably 50% or more. In the present invention, the vinyl polymer emulsion can be obtained by a known emulsion polymerization method. This method includes () bulk purchasing method (monomer,
(method in which an emulsifier, catalyst, water, etc. are charged together into a reaction vessel and polymerization is carried out at a relatively low temperature of 50 to 60°C or less for a long time), () monomer addition method [all emulsifier and water , or a polymerization method in which some monomers and a catalyst are also charged into a reaction vessel as necessary, and the monomers (and the catalyst, if necessary) are added sequentially as the polymerization progresses] and () Monomer Emulsion addition method [Part of the emulsifier, water, catalyst, etc. are placed in a reaction vessel, the remaining emulsifier is used to emulsify the monomer and water, and as the polymerization progresses, this emulsion (and the catalyst, if necessary) is added sequentially as the polymerization progresses. Post-addition polymerization method] is mentioned. Among the above three types of emulsion polymerization methods, the preferred method is the monomer addition method. In the present invention, the catalyst (polymerization initiator) used when polymerizing the monomers includes inorganic peroxides such as persulfates (ammonium persulfate, potassium persulfate, sodium persulfate, etc.), organic peroxides such as peroxide Diacyls (benzoyl peroxide, etc.), dialkyl peroxides (di-t-butyl peroxide, etc.), hydroperoxides (cumene hydroperoxide, etc.), azo compounds (azobisisobutyronitrile, azobisdimethyl chlorphotonitrile, etc.) and peroxides with reducing agents such as sulfites (sodium sulfite, etc.), acid sulfites (sodium bisulfite, etc.), and ferrous salts (ferrous ammonium sulfate, etc.). . Among the above catalysts, inorganic peroxide catalysts are preferred. The amount of catalyst used is usually 0.01 to total monomers.
It may be 0.7%, preferably 0.05-0.5%. Further, a PH regulator such as sodium hydrogen carbonate may be used in combination. The polymerization temperature is usually 40 to 90°C, preferably 50 to 80°C. The polymerization time is usually 2 to 10 hours, preferably 3 to 6 hours. The resulting vinyl (co)polymer emulsion has a solid content of 40%.
The viscosity at 25℃ is usually 30cp to 200cp. Moreover, the monomer polymerization conversion rate is usually 97% to 100%. The vinyl (co)polymer emulsion obtained by the method of the present invention has low foaming property and polymerization stability (specifically, the amount of aggregates generated during polymerization).
is excellent. Furthermore, although the vinyl (co)polymer emulsion obtained by the method of the present invention contains (A), which is an anionic surfactant, it has unexpectedly high chemical stability (specifically, against electrolytes). stability), and other mechanical stability and storage stability were also good. Vinyl type (co) produced by the method of the present invention
It is useful in a wide range of applications such as polymer emulsions, paint vehicles, adhesives, paper processing agents, and textile processing agents. The present invention will be further explained below with reference to Examples.
The present invention is not limited to these examples. All parts shown in Examples are parts by weight. Example 1 In a reaction vessel equipped with a stirrer, a nitrogen gas inlet tube, a thermometer, a reflux condenser, and a dropping funnel, 150 parts of degassed ion-exchanged water, 4 parts of the emulsifier of the present invention, 0.1 part of sodium bicarbonate, and ammonium persulfate were added. 0.3 part of the solution was added and dissolved, and after bubbling nitrogen gas at room temperature for 15 minutes, the temperature was raised to 80°C, and 100 parts of butyl acrylate was uniformly added dropwise over 3 hours to effect polymerization. After completion of the dropping, aging was performed for 1 hour to obtain a butyl polyacrylate emulsion. Table 1 shows the emulsifiers used.

[Table] Test results of butyl polyacrylate emulsions produced using the emulsifiers listed in Table 1 are shown in Table 1.
Shown in 2.

[Table] Example 2 Emulsion polymerization was carried out in the same manner as in Example 1 except that vinyl acetate was used as the vinyl monomer in Example 1 to obtain a polyvinyl acetate emulsion. The test results of the obtained polyvinyl acetate emulsion are shown in Table 3.

[Table] As shown in the above examples, the vinyl polymer emulsion produced by the method of the present invention has a low foaming property equivalent to or more than that of the conventional emulsion that does not use polyoxyethylene styrenated phenylether, It also has very good polymerization stability.
The physical properties of the vinyl polymer emulsion were also good.

Claims (1)

[Claims] 1 A polyoxyalkylene styrenated or/and benzylated phenyl ether sulfate salt (A) of a vinyl monomer, and if necessary, other anionic surfactants and nonionic surfactants. A method for producing a vinyl polymer emulsion, comprising carrying out emulsion polymerization in the presence of at least one compound (B) selected from the group consisting of , and water-soluble oligomers. 2 (A) is a general formula (In the formula, m ¹ is an integer of 1 to 3, A ¹ is an alkylene group having 2 to 3 carbon atoms, n ¹ is an integer of 1 to 100, and M ¹ is an alkali metal, ammonium, or amine cation.) The manufacturing method according to claim 1, which is an oxyalkylene styrenated phenyl ether sulfate salt. 3 (A) is a general formula (In the formula, m ² is an integer of 1 to 3, A ² is a carbon number of 2 to 3
( ⁿ² is an integer of 1 to 100, ^M2 is an alkali metal, ammonium or amine cation) is a polyoxyalkylene benzylated phenyl ether sulfate salt represented by manufacturing method. 4 (A) is a general formula (In the formula, m ³ and m ⁴ are integers of 1 to 2, and m ³ + m ⁴
= 2 to 3, A ³ is an alkylene group having 2 to 3 carbon atoms,
n ³ is an integer of 1 to 100, M ³ is an alkali metal, ammonium or amine cation. Law.