JPS6270426A - High-solid aqueous polymer dispersion - Google Patents

Abstract

PURPOSE:To obtain the titled dispersion which is excellent in mechanical, chemical and freezing stability, can keep a low viscosity and can give a film excellent in water resistance and strength, by adding a metaphosphate, a polyphosphate, an ultraphosphate or a combination thereof to an aqueous polymer dispersion and concentrating this dispersion. CONSTITUTION:For example, 1-10wt% ethylenically unsaturated dicarboxylic acid (e.g., fumaric acid) is emulsion-polymerized with 10-90wt% aliphatic conjugated diene (e.g., butadiene) and 9-80wt% other ethylenically unsaturated monomers [e.g., methyl (meth)acrylate] to obtain an aqueous dispersion (A) of a polymer such as a butadiene copolymer. To 100pts.wt. (in terms of solid matter) component A, 0.5-2.0pts.wt. metaphosphate of formula I (wherein M is Na, K or Ca and n is a positive integer), a polyphosphate, an ultraphosphate of formula III or a combination thereof is added, and the mixture is concentrated at 50-70 deg.C and a pressure of 500-600mmHg in, for example, a stripping kettle to obtain the titled dispersion of a solid content >=50wt%.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a high solids content polymer aqueous dispersion having extremely excellent stability. More specifically, the present invention relates to an aqueous polymer dispersion that has excellent mechanical stability, chemical stability, and freezing stability, and maintains a low viscosity even in a state containing a high solid content.

[Conventional technology]

Traditionally, polymer aqueous dispersions include styrene butadiene latex, acrylonitrile butadiene latex,
Methyl methacrylate butadiene latex, chlorozolene latex, polyurethane-based, polyester-based, acrylic-based, vinyl acetate-based emulsions, etc. have been commercialized. However, since these polymer aqueous dispersions are in the form of hydrophobic polymer particles dispersed in an aqueous medium, the particles tend to aggregate due to external forces, and various additives When such agents are mixed, the dispersion stability of particles may be inhibited, leading to an increase in viscosity over time and aggregation of particles. Furthermore, since the dispersion medium is water, the dispersion liquid freezes when the temperature falls below 0°C. Once frozen, even if the temperature is raised to 0°C or higher and thawed, the particles often remain agglomerated and do not return to their pre-freezing state. The common drawbacks of these aqueous polymer dispersions cause many problems in actual use, such as deterioration and instability during storage, gumming up and coagulation during processing. On the other hand, these aqueous dispersions utilize the adhesive strength and film properties of the polymer that develops after the water, which is the dispersion medium of the polymer particles, is evaporated off by heating etc. during the usage process, and are used as fiber processing agents, adhesives, etc. It is used for various purposes such as paint. Therefore, it is preferable to use as little water as a dispersion medium as possible in the process of use, that is, the higher the solid content of the dispersion liquid, the better from the point of view of energy saving and production efficiency. Furthermore, when producing, storing, and transporting an aqueous polymer dispersion, the higher the solid content, the more advantageous it is in terms of production efficiency, container cost, transportation cost, etc.

However, as the proportion of water as a dispersion medium decreases, the polymer aqueous dispersion obtained by the conventional method increases the chances of contact between polymer particles, making it easier to aggregate, resulting in poor polymerization stability. , it is not possible to obtain a dispersion with a high solid content concentration due to lack of storage stability.

Furthermore, since the amount of dispersion medium is reduced, the viscosity of the dispersion liquid becomes high, which exceeds the practical range of handling workability in transportation, storage, and workability in dressing and processing steps. Therefore, it would be ideal to have a dispersion with high solids content, low viscosity, and excellent mechanical, chemical, and freeze stability. The solid content of molecular dispersion liquids is generally about 50% or less, and the mechanical, chemical stability, freezing stability, etc. are also insufficient at present. Of course, aqueous dispersions with a solid content of 50% or more are also available on the market, but the stability described above is not satisfactory.

For this reason, great efforts have been made and many studies have been made to reduce the viscosity of high solids content and improve the stability.

For example, by enlarging polymer particles, the viscosity can be reduced.
It is known that high solidity differentiation is possible, including seed polymerization, addition of m-medium, addition of colloidal active substances, strong stirring,
Attempts have been made to enlarge the particles by means such as adding electrolytes and freezing and then thawing. However, although it is possible to achieve low viscosity and high solidity, these properties do not satisfy mechanical and chemical stability, and have the disadvantage of decreasing water resistance, strength, etc. Many of them are also complex.

[Problem that the invention seeks to solve]

To this end, the present invention has been prepared in an attempt to solve various problems faced by the prior art as described below.

(I) Conventional aqueous polymer dispersions have a solid content of 50 grams or more and do not have sufficient mechanical stability, chemical stability, freezing stability, etc. In particular, this tendency becomes stronger as the Tg becomes lower.

(2) High solidity differentiation, low viscosity When polymer particles are enlarged to improve stability, the water resistance, strength, etc. of the aqueous polymer dispersion decrease.

(3) Generally, the manufacturing process is complicated.

[Failure to solve the problem] The present inventors have developed a polymer that has excellent mechanical, chemical, and freeze stability, and maintains low viscosity even in a high solid content state without taking measures such as particle enlargement. As a result of intensive research into aqueous dispersions, the inventors discovered that adding a specific phosphate to a polymer aqueous dispersion to perform concentration best met these requirements, leading to the completion of the present invention. .

That is, in the present invention, metaphosphate (I), polyphosphate (I[), and ultraphosphate (I1) represented by the following structural formulas are added alone or in combination to a polymer aqueous dispersion and concentrated. This is an aqueous polymer dispersion with a high solids content.

(I) (MPO3).

n; positive integer (I[l) Na2p4o,.

Examples of the metaphosphate (I) of the present invention include acidic sodium metaphosphate, calcium metaphosphate, calcium sodium metaphosphate, sodium metaphosphate, and potassium metaphosphate, particularly sodium hexametaphosphate (n=6, M=N
a) is preferred. Polyphosphoric acid (If) Examples include sodium pyrophosphate, potassium birophosphate, sodium tripolyphosphate, and sodium tetrapolyphosphate, with sodium tripolyphosphate (n=3, MxNa) being particularly preferred.

Although these (I), (II), and (In) can be used alone, it is preferable to use sodium hexametaphosphate and sodium tripolyphosphate in a ratio of 1:1 to 1:0.5 (
It is even more effective when used in combination within the range of superposition ratio).

The metaphosphate, polyphosphate, and ultraphosphate of the present invention are not particularly limited in usage, but are preferably used in a range of 0.5 to 2.0 parts by weight based on 100 parts by weight of the solid content of the aqueous polymer dispersion. used in

Metaphosphate (I), polyphosphate (It) of the present invention,
There are no particular restrictions on the method of adding ultraphosphate (III), but for example, it may be added directly to a polymer aqueous dispersion, or it may be added to water and a potassium hydroxide water bath solution in mM.
It may be added and mixed.

After the addition, the concentration step (S) (IJpping) is carried out using a conventional method, namely (S) IJpping kettle.

There are no restrictions on the conditions, etc., but usually 50 to 70
Preferably, it is concentrated at 500 to 600 degrees Celsius.

The solid content in the present invention usually refers to a solid content of 50% by weight or more, preferably 55% by weight or more.

The polymer aqueous dispersion used in the present invention is water tm
A general term for resins in a semi-dissolved or dispersed state as a medium, and in some cases containing a small amount of organic magent, such as butadiene-based copolymers; butadiene-styrene copolymers, butadiene-acrylonitrile copolymers, polybutadiene, etc. and acrylic copolymers, aqueous polyurethane resins, aqueous polyester resins, and mixtures thereof.

The butadiene-based copolymer preferably contains 10 to 90% by weight of butadiene as an essential component, particularly 20 to 90% by weight.
A copolymer containing ~801% by weight, preferably consisting of 9 to 80% by weight of another monomer copolymerizable with butadiene as a copolymer component, and 1 to 10% by weight of an ethylenically unsaturated dicarboxylic acid. .

The butatsuene-based copolymer has the above composition in the presence of an aqueous polymer dispersion containing ethylenically unsaturated monocarginic acid as a copolymerization component, preferably 0.5 to 2.5 parts by weight as solid content. The more emulsion polymerized the product, the greater the effect of adding sodium hexametaphosphate and sodium tripolyphosphate.

Other monomers are ethylenically unsaturated monomers such as methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, globil methacrylate, butyl acrylate, butyl methacrylate. , polymethyl acrylate, intyl methacrylate,
Hexyl acrylate, hexyl methacrylate, hebutyl acrylate, heptyl methacrylate, octyl acrylate, octyl methacrylate, octadecyl acrylate,
Acrylic acid alkyl esters and methacrylic acid alkyl esters exemplified by octadecyl methacrylate, etc., styrene, α-methylstyrene, vinyltoluene, chlorostyrene%, ethylenically unsaturated aromatic compounds exemplified by 2,4-dibromustyrene, etc. monomer, acrylonitrile,
Unsaturated nitriles such as glycymethacrylate, vinyl acetate,
Vinyl esters such as vinyl propionate, acrylic acid,
Ethylenically unsaturated carboxylic acids such as methacrylic acid, itaconic acid, fumaric acid, vinylidene halides such as vinylidene chloride, vinylidene bromide, etc., ethylenic unsaturated carboxylic acids such as 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, etc. Saturated Cal? hydroxyalkyl ester of phosphoric acid, glycidyl acrylate, glycidyl methacrylate
) glycidyl esters of ethylenically unsaturated caldicic acids such as acrylamide, methacrylamide, N-
Examples include methylol acrylamide, N-methylol methacrylamide, N-butoxymethyl acrylamide, and diacetone acrylamide.

Examples of ethylenically unsaturated dicarboxylic acids include itaconic acid,
Examples include one or more of fumaric acid, maleic anhydride, crotonic acid, and the like.

The acrylic copolymer (I) has 1 to 18 carbon atoms;
At least one selected from acrylic acid alkyl esters having an ester alkyl group, and methacrylic acid alkyl esters having an ester alkyl group having 4 to 18 carbon atoms
30 to 99.9% by weight of seed monomers, (2) 0.1 to 10% by weight of at least one α,β-monoethylenically unsaturated caldic acid, and (3) co-monomers with An aqueous acrylic polymer dispersion obtained by emulsion copolymerization with O to 69.9% by weight of at least one other polymerizable α,β-monoethylenically unsaturated monomer is preferred.

Acrylic acid alkyl ester having an ester alkyl group having 1 to 18 carbon atoms of the above (I), having 4 to 18 carbon atoms
Typical methacrylic acid alkyl esters having 18 ester alkyl groups include ethyl acrylate, n-propyl acrylate, isozorobyl acrylate, n-butyl acrylate, isobutyl acrylate, and n-octyl acrylate. , 2-ethylhexyl acrylate, decyl acrylate, octadecyl acrylate; n-butyl methacrylate, n-octyl methacrylate, 2-ethylhexyl methacrylate, dodecyl methacrylate, octadecyl methacrylate, and the like. These monomers are used to give flexibility to the acrylic copolymer, and their proportion is 30% of the total monomers.
If the amount is less than % by weight, the effect will not be sufficient.

α,β-monoethylenically unsaturated cal in (2) above? Examples of acid include acrylic acid, methacrylic acid, crotonic acid, maleic acid, fumaric acid, itaconic acid and unsaturated dicarboxylic acid monoalkyl esters such as monomethyl maleate,
Examples include monoethyl fumarate and mono-n-butyl itaconate. These monomers are necessary components for increasing the mechanical stability and freezing stability of the copolymer, and further increasing the adhesion of the film to the fibers, and their proportion is 0% of the total monomers. If it is less than 1% by weight, there is no effect, and if it exceeds 10% by weight, the water resistance of the film will decrease.

Other α copolymerizable with the above (I) and (2) component monomers
.

Examples of the β-monoethylenically unsaturated monomer (3) include methyl methacrylate, ethyl methacrylate, n methacrylate
-Propyl, inzolovir methacrylate, styrene, alpha
-Methylstyrene, vinyltoluene, chlorstyrene,
2.4-Dibromustyrene, acrylonitrile, methacrylonitrile, vinyl acetate, vinyl propionate, vinyl chloride, vinylidene chloride, vinylidene bromide, etc. Mainly for imparting hardness or specific performance to the composition film monomers, as well as acrylamide, methacrylamide, N-methylolmethacrylamide, N-butoxymethylacrylamide, N-butoxymethylmethacrylamide, diacetone acrylamide, hydroxymethyldiacetone acrylamide, glycidyl acrylate, glycidyl methacrylate, acrylic Functional group content that can be crosslinked by heat and acidic catalysts such as 2-hydroxyethyl acid, 2-hydroxyglobyl acrylate, 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, etc. An example of this is the placement of a body.

These monomers are used in an amount of 69.9% by weight or less of the total monomers.

The aqueous polyester resin of the present invention is: (1) a copolymer of dicardic acid having an alkali metal sulfonic acid salt in its aromatic nucleus, (2) a polyester with a polycarboxylic acid anhydride added and neutralized with a base, and (2) a polyethylene glycol. Examples include those obtained by copolymerizing (2), those dispersed using an emulsifier, and those resulting from a combination thereof.

Examples of the dicardic acid having an alkali metal sulfonic acid salt in the aromatic nucleus used in the aqueous polyester resin (2) include alkali metals such as sulfoterephthalic acid, 5-sulfoisophthalic acid, and 4-sulfonaphthalene-2,7-dicarboxylic acid. Salt is an example. Also included are ester-forming derivatives commonly used in the production of polyester resins, such as lower alcohol esters such as methyl ester and ethyl ester of these carzenic acids. Among these, the most preferred alkali metal salts of 5-sulfoisophthalic acid and sulfoterephthalic acid are sodium salt and potassium salt. The alkali metal sulfonic acid salt-containing compound is an essential component for making the polyester resin water-soluble, and its content naturally affects the dissolvability of the polyester resin. The aqueous polyester resin of the present invention includes those that are transparent and dispersed in water to form an emulsion, and this can be adjusted depending on the content of the alkali metal sulfonic acid salt-containing compound. Ru. If this amount is more than 15 mol of the total carboxylic acid components, the water resistance of the resulting resin will be markedly reduced, which is not preferable. On the other hand, if the amount is less than 3 moles, the hydrophilicity becomes insufficient and a stable aqueous s91) ester resin cannot be obtained, and furthermore, the stability is significantly reduced, which is not preferable. A more preferred amount is 5 to 10 molti of the total carboxylic acid component.

Other aromatic carboxylic acids include terephthalic acid, isophthalic acid, phthalic anhydride, 2,6-naphthalenesocarginic acid, biphenyldicarboxylic acid, trimellitic anhydride,
Examples include pyromellitic anhydride, and ester-forming derivatives thereof are also included.

Such aromatic carboxylic acids, including dicarboxylic acids having an alkali metal sulfonic acid salt in the aromatic nucleus, need to be used at least 50 mol/I/bic acid components, but if it is less than 950 mol, the mechanical properties of the resulting resin will deteriorate. In addition, the adhesiveness increases.1 For example, when used as an adhesive, it will not peel off due to severe blocking when it is coated, rolled up after drying, and hot-melted at a later date.
This is not preferable because it causes a decrease in workability. The amount of aromatic carboxylic acid used is preferably 70 molti or more, particularly preferably 70 to 97 molti.

Carboxylic acids other than aromatic carginic acid include aliphatic acids such as succinic acid, maleic acid, fumaric acid, anopic acid, pimelic acid, superric acid, azelaic acid, sepacic acid, dimer acid, and cyclohexanedicarginic acid; Examples include alicyclic carboxylic acids and ester-forming derivatives thereof.

Among all the carboxylic acids, these carginic acids are
It is used within the range of residual p other than phosphoric acid. Further, the polyol component is not particularly limited, and all polyols commonly used for polyester resins can be used.

For example, ethylene glycol, diethylene glycol, flobile/glycol, 1.4-bucundiol, neointyl glycol, 1.6-hexanediol, 1.4
-Cyclohexane dimetatool, 1,4-bis(hydroxyethoxy)benzene, hydrogenated bisphenol A, polyoxyethylene glycol, yle IJ oxypropylene glycol, polyoxytetramethylene glycol, chrycerin, trimethylolpropane, trimethylolethane, penta Examples include erythritol.

When the content of alkali metal sulfonic acid salt is relatively large when making such a polyester resin water-based, the temperature is 40°C to 10°C.
It can be self-dispersed and made aqueous by simply stirring in warm water at 0°C, but if the content of alkali metal sulfonate is relatively low and it is difficult to make it aqueous, use a small amount of organic solvent, such as lower alcohols or glycols. , cellosolves,
It can also be made aqueous with the help of cyclic ethers, ketones, etc.

The aqueous polyurethane resin used in the present invention is a polyurethane prepolymer made of a polyol such as a polyester polyol or a polyether polyol and an aromatic, aliphatic, or alicyclic diisocyanate, and a polyurethane prepolymer made of a polyol such as a polyester polyol or a polyether polyol and an aromatic, aliphatic, or alicyclic diisocyanate. This refers to polyurethane resins whose chains have been extended by the introduction of low molecular weight polymers, which have been stably dispersed or electrolyzed in water. The following methods are known as methods of dispersion or electrolysis.

(I) Completely reacted polymer or terminal isocyanate)
Basic rough flocs (oxime, alcohol, phenol,
A method in which polymers blocked with mercaptans, amines, sodium bisulfite, etc.) are forcibly dispersed in water using an emulsifier and mechanical shearing force. Furthermore, a method in which a urethane prepolymer having a terminal incyanate group is mixed with water, an emulsifying agent, and a chain extender, and mechanical shearing force is used to simultaneously perform dispersion and polymerization.

(2) A method of imparting hydrophilicity by introducing ionic groups such as hydroxyl groups, amino groups, and carboxyl groups to the side chains or terminals of polyurethane polymers, and dispersing or electrolyzing them in water by self-emulsification.

(3) As a polyol, the main raw material for polyurethane)
A method of dispersing or electrolyzing a water-soluble polyurethane resin in water using a water-bathable polyol such as diethylene glycol.

The aqueous, i? IJ urethane resin is
The present invention is not limited to a single method of dispersion or m-solution described above, but mixtures obtained by each method can also be used. When used in combination with the aqueous 351J ester resin of the present invention, a nonionic water-dispersible or anionic aqueous polyurethane resin is particularly preferred in terms of mixing stability and water resistance. For example, commercially available products include the "Dandik" series, the "Hytran" series (manufactured by Dainippon Ink & Chemicals Co., Ltd.), and the "Inplanil" series (manufactured by Bayer).
etc.

Examples of the emulsifier used in the emulsion polymerization of the present invention include anionic surfactants, nonionic surfactants, water-based polymeric substances, etc., but they are usually anionic, nonionic, and anionic and nonionic. The combination system is used in an amount of 0.1 to 10% by weight based on the total amount of the single company.

In addition, all polymerization aids used in ordinary emulsion polymerization can be used without particular limitation. Examples include chain transfer agents, ethylenediaminetetraacetic acid for polymerization stabilization and buffering effects, PL (alkaline substances for adjustment may be used as necessary, potassium persulfate, ammonium persulfate, etc.) as polymerization initiators, etc. persulfates and hydrogen peroxide,
Inorganic and organic peroxides such as cumene hydroperoxide and tertiary butylhydrono-9-oxide, and these peroxides, ferrous salts, and sodium bisulfite.1. d A redox initiator in combination with a water bath reducing agent such as IJ amine can be used.

The various monomers mentioned above may be added all at once, in portions, or by continuous dropwise addition, and the polymerization temperature is 0 to 100.
Polymerization is carried out in the range of °C. After completion of polymerization, use pi as necessary.
(Perform adjustments, etc.)

〔effect〕

The aqueous polymer dispersion of the present invention has excellent mechanical stability, chemical stability, and freezing stability when containing crystalline solids,
It also maintains a low viscosity, and the resulting film has sufficient water resistance and strength, which is advantageous in terms of production efficiency, container costs, transportation costs, etc., and on the other hand, in terms of applications, the high solid content reduces drying time. Energy savings can be expected.

Therefore, the high solid content polymer aqueous dispersion of the present invention can be used, for example, in foam coatings for textile products, backing agents for carpets, adhesives (for non-woven fabrics, metals, vinyl chloride), printing binders, fiber processing agents, fibers, etc. Gluing agent, hard finishing agent, coating agent, paper use e.g. paper impregnating agent 5 Paper processing agent, paint e.g. sushi paint, anti-corrosion paint, bottle coat paint, civil engineering and construction use e.g. cement admixture, filler, plywood adhesive It can be used in a wide range of applications, including as a compound paste resin and for impregnation molding.

〔Example〕

The present invention will be explained below with reference to Examples. In addition, "part" in the example
and ``%'' are based on the 9th grade company standard unless otherwise specified.

[Examples 1 to 3] One part of ion-exchanged water was placed in a nitrogen-substituted autoclave with a stirrer.
10 parts, Rankstar DS-801 (butanoene-based copolymer manufactured by Inu Nippon Ink Chemical Industry Co., Ltd.) as solid content: 1
．． 0 parts, sophenyl ether sulfo C91) Ecol 2F 1A in sodium chloride, manufactured by Nippon Nyukazai) 1.
0 part, 0.5 part of tertiary dodecyl mercaptan, and 0.1 part of ammonium ethylenediaminetetraacetate were added to 100 parts of the monomers having the composition shown in Table 1, A, B, and C, and 0.5 part of potassium persulfate was added. Emulsion polymerization was carried out at 60° C. with stirring until the polymerization rate reached 98 degrees or more. Next, add 1.0% of hexametaphosphate to the aqueous polymer dispersion after polymerization.
A and B in Table 1 were obtained by adding 0.5 parts of sodium tripolyphosphate dissolved in a 10% potassium hydroxide m solution, removing unreacted single solids by steam distillation, and concentrating.

Good latexes A, B, and C shown in C were obtained.

It was found that all of these had high solid content and low viscosity as shown in Table 1.

[Comparative Example 1] Emulsion polymerization was carried out in the same manner as in Example 1, and then the concentration was adjusted to 8.7 using only 10-dipotassium hydroxide liquor without using sodium hexamecrate or sodium tripolyphosphate. D shown in Table 1 was obtained.

It was found that this product had a higher viscosity than that of the example.

[Examples 4 to 5] In a stainless steel reaction vessel, 120 parts of ion-exchanged water and an alkylbenzenesulfonic acid sorter (Neoperex F-
25. 0.3 parts (manufactured by Kao Soap), then 0.4 parts of ammonium persulfate and 0.2 parts of sodium bicarbonate were added, allowed to dissolve, and heated to 75-80°C in a nitrogen stream. 10 parts of a monomer emulsion prepared by emulsifying the monomer composition of No. 5 and 0.3 parts of sodium argylbenzenesulfonate (Neoperex F-25, manufactured by Kao Soap) in 30 parts of water were charged to start polymerization. I let it happen. After 30 minutes, the remaining monomer emulsion was added dropwise at the same temperature for 180 minutes to copolymerize, and then held for 30 minutes to complete the copolymerization.
An aqueous polymer dispersion shown in 2 was obtained.

Next, 1.0 part of sodium hexametaphosphate and 0.5 part of sodium tripolyphosphate were dissolved in water and added to the polymer aqueous dispersion after emulsion polymerization and concentrated to obtain the polymer water shown in Table 2. The dispersion iE,F was obtained.

It was observed that this product exhibits low viscosity at high solids content.

[Comparative Examples 3 and 4] Emulsion polymerization was carried out using the same monomer composition and prescription as in Examples 4 and 5, and concentrated without using sodium hexametaphosphate and sodium tripolyphosphate to obtain polymer aqueous dispersion G, f(
I got it.

It was found that this product had an extremely high viscosity compared to the corresponding Examples 4 and 5, respectively.

Physical Properties Test> Various physical properties of the obtained polymer aqueous dispersions A to H were measured.

(I) Film tensile strength and water resistance The film was cast onto a glass plate so that the dry film thickness was 0.5 to 0.7 tm, and air-dried at 20°C for 48 hours. A specimen was punched out using a Tensilon machine, and the strength and elongation of the film was measured at a tensile speed of 500 m+/ml n.

Water resistance was determined by observing the state of the film after immersing it in water for 48 hours.

(2) Place the freeze-stable polymer aqueous dispersion in a 100 cc glass bottle, tightly stopper it, let it stand at -10°C for 10 hours, and then leave it at room temperature for 8 hours.One cycle is the number of cycles until gluing. It was shown in

(3) Mechanical stability Using a Marlon-type stability tester (rotation speed: 1000 rpm), the weight of the produced coagulated product relative to the solid weight of the sample is measured.

Table 12 As shown in Table 2, these results show that by adding and concentrating the specific phosphate of the present invention, the particles are not enlarged, the water resistance of the film is improved, there is no decrease in tensile strength, and there is no decrease in freezing. It was recognized that the product had excellent stability and mechanical stability.

/′

Claims (1)

[Claims] 1. After adding metaphosphate (I), polyphosphate (II), and ultraphosphate (III) represented by the following structural formula to a polymer aqueous dispersion, either singly or in combination. Concentrated high solid content polymer aqueous dispersion (I) (MPO_3)_n (II) M_n_+_2P_nO_3_n_+_1 (III
) Na_2P_4O_1_1 M: Na, K, Ca2, n: Positive integer 2, the polymer aqueous dispersion emulsion polymerizes ethylenically unsaturated dicarboxylic acid, aliphatic conjugated diene and other ethylenically unsaturated monomers. A high solid content polymer aqueous dispersion according to claim 1, which is obtained.