JPH0786163B2 - Self-crosslinking resin aqueous dispersion composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The self-crosslinking resin aqueous dispersion composition of the present invention is used as a coating material for wood, metal, paper, resin molded articles, adhesives and emulsion for polymer cement. Is useful as

[Prior art]

A room temperature crosslinkable aqueous dispersion of a carbonyl group-containing copolymer containing a hydrazine derivative is known (JP-A-54-11).
0248, 54-144432, 55-147562, 57-3857
No. 58-96643, No. 60-38468). This aqueous dispersion forms a film at a film forming temperature of 5 to 25 ° C. Moreover, it is noteworthy to provide a film having a strong adhesion to the adherend such as cloth and metal.

For example, in JP-A-54-144432, (a) an aqueous dispersion of a carbonyl group-containing copolymer having a glass transition temperature of 0 to 50 ° C., (b) a water-soluble aliphatic dihydrazine compound and (c) Water-soluble zinc salt, manganese salt, cobalt salt or iron salt coating binder was applied to a cotton cloth tape, what formed a film, measured with a roll stripping device according to DIN 53-289 2 kg It states that a cotton cloth tape having a fixing force of /3.5 cm was obtained.

The aqueous resin dispersion compositions described in the above publications are prepared by adding an aqueous dispersion of a carbonyl group-containing copolymer to an aqueous solution of an adipic acid dihydrazide or a polymer hydrazine derivative having two or more —NH.NH ₂ groups. When blended, the hydrazine derivative cross-links with the carbonyl groups of the copolymer upon drying to give a film. This film has excellent hardness, elongation and chemical resistance.

[Problems of conventional technology]

When the above-mentioned aqueous dispersion composition is used as a metal coating agent, improvement in rust prevention and in water resistance of the obtained coating film are desired.

[Specific means for solving problems]

In the present invention, (A) an acrylic copolymer having two or more hydrazine residues, which is obtained by reacting an aqueous dispersion of an acrylic copolymer having an amide group and / or an ester group with hydrazine hydrate. A combined aqueous dispersion,
(B) a carbonyl group-containing copolymer aqueous dispersion,
With respect to 1 equivalent of the carbonyl group of the copolymer of the component (B),
The hydrazine residue of the acrylic copolymer of component (A) is 0.
A film having excellent water resistance can be obtained by using the self-crosslinking resin aqueous dispersion composition prepared by mixing so as to have an amount of 05 to 5 molar equivalents.

Component (A): An aqueous dispersion of an acrylic copolymer having two or more hydrazine residues as the component (A) is an aqueous dispersion of an acrylic copolymer having an amide group and / or an ester group, and hydrazine. It is obtained by reacting with a hydrate, and is reacted, for example, at 70 to 130 ° C.

Immediately, in the present invention, unlike the oligomer, the one obtained by reacting an aqueous dispersion composed of a copolymer having a higher molecular weight than the oligomer with hydrazine hydrate is used as the component (A), so that the water resistance and the rust prevention It has a special effect of being excellent in physical properties such as properties.

An aqueous dispersion of an acrylic copolymer having an amide group and / or an ester group as a raw material is, for example, (a). Monomers selected from methyl methacrylate, vinyl aromatic compounds, tertiary butyl acrylate, tertiary butyl methacrylate, vinyl halides, ethylene 0-80
% By weight (b). 95 to 20% by weight of a monomer selected from esters of acrylic or methacrylic acid of alkanol having 2 to 8 carbon atoms, vinyl esters, methyl acrylate and 1,3-diene. (C). Carbonyl group-containing monomer having at least one aldo group or keto group and one polymerizable double bond in the molecule 0 to 20% by weight (d). Mono having 3 to 5 carbon atoms or / And / or dicarboxylic acids or / and amides of these acids substituted by alkyl or / and alkylol groups having 1 to 4 carbon atoms at the nitrogen atom 0.1 to 30% by weight (e). Acrylonitrile, methacrylonitrile, 0
It is obtained by emulsion polymerization of the vinyl monomers (a) to (e) in the above proportions.

The vinyl monomer of the component (a), that is, methyl methacrylate, vinyl aromatic compound such as styrene, tertiary butyl acrylate, tertiary butyl methacrylate, halogenated vinyl ester such as vinyl chloride and / or vinylidene chloride, Ethylene is used in an amount of 0 to 80% by weight, preferably 20 to 70% by weight in the copolymer.

Examples of the vinyl monomer as the component (b) include alcohols having 2 to 8 carbon atoms such as ethanol, isopropanol, n-propanol, n-butanol, isobutanol or 2-ethylenehexanol and acrylic acid and / or methacryl. Esterified from acid,
Methyl acrylate, vinyl acetate, vinyl propionate,
1,3-dienes (eg butadiene). Among these, 2-ethylhexyl acrylate, n-butyl acrylate, ethyl acrylate, and methyl acrylate are preferable. The monomer of component (b) is used in an amount of 95 to 20% by weight, preferably 80 to 30% by weight in the copolymer.

Further, as the carbonyl group-containing monomer of the component (c),
Monomers having at least one aldo group or keto group and one polymerizable double bond in the molecule, that is, particularly polymerizable monoolefinic unsaturated aldo compounds and keto compounds, which are ester groups (-COO-) and compounds having only a carboxy group (-COOH) are excluded. Specifically, acrolein, diacetone acrylamide, formyl styrene, preferably a vinyl alkyl ketone having 44 to 7 carbon atoms, for example vinyl methyl ketone,
Vinyl ethyl ketone and vinyl isobutyl ketone and /
Or the following formula (Wherein R ¹ is H or CH ₃ , R ² is H or an alkyl group having 1 to 3 carbon atoms, R ³ is an alkyl group having 1 to 3 carbon atoms, and R ⁴ is 1 to 4 (Meaning an alkyl group having a carbon atom of), acryl (methacryl) oxyalkylpropanal, diacetone acrylate, acetonyl acrylate, diacetone methacrylate, acetonitrile methacrylate, 2-hydroxypropyl acrylate-acetylacetate and butanediol. -1,4-acrylate-acetylacetate is used.

Among these, acrolein, diacetone acrylamide, and vinyl methyl ketone are preferable.

The carbonyl group-containing monomer as the component (c) is used in an amount of 0 to 20% by weight, preferably 7% by weight or less in the copolymer.

Further, as the monomer of the component (d), a mono- and / or dicarboxylic acid having 3 to 5 carbon atoms which is monoolefinically unsaturated, such as acrylic acid, methacrylic acid, itaconic acid, maleic acid and fumaric acid. And citraconic acid and /
Or an amide thereof such as acrylamide, methacrylamide, and / or its N-alkyl or N-alkylol derivative such as N-methylacrylamide, N-
Isobutyl acrylamide, N-methyl methacrylamide, N-methylol acrylamide, N-methylol methacrylamide, N-ethoxymethyl acrylamide,
Examples thereof include Nn-butoxymethyl acrylamide and N-isopropoxy methacrylamide, and of these, acrylic acid, methacrylic acid, itaconic acid, acrylamide and methacrylamide are preferable.

The vinyl monomer as the component (d) is 0.1% in the copolymer.
It is used in an amount of -30 wt%, preferably 0.5-10 wt%.

If necessary, in addition to these vinyl monomers (a) to (d), 0-40% by weight of acrylonitrile or methacrylonitrile or / and mono-olefinic unsaturated sulfonic acid may be added.
An amount of 10% by weight or less is added, and the type and amount of each vinyl monomer are determined so that the glass transition temperature of the copolymer obtained by emulsion polymerization is −85 ° C. to 60 ° C.

Aqueous dispersions of this copolymer can be prepared by copolymerizing the monomers in an aqueous emulsion with conventional emulsifiers and dispersing aids by conventional means, and often 40-
It has a copolymer concentration of 60% by weight. The emulsifier and dispersion aid often contain 0.2 to 3% by weight of anionic and / or nonionic emulsifier, based on the amount of copolymer. Examples are: Sodium dialkyl sulfone succinate, sodium salt of sulfated oil, sodium salt of alkyl sulfonic acid, potassium salt and ammonium alkyl sulfate, alkali metal salt of sulfonic acid, sulfuric acid of oxyalkylated C ₁₂ -C ₂₄ -aliphatic alcohol Half-ester alkali metal salts and sulfuric acid of oxyalkylated alkylphenols, half-ester alkali metal salts and other oxyethylated fatty acids, fatty alcohols and / or aliphatic amides, oxyethylated alkylphenols, and of fatty acids Sodium salts such as sodium stearate and sodium oleate.

Component (B): The liquid having a carbonyl group of the component (B) is the above-mentioned (c)
The carbonyl group-containing vinyl monomer of 0.5 to 60% by weight and another vinyl monomer are obtained by emulsion polymerization in an aqueous dispersion, and the concentration of the copolymer is 35 to 60% by weight. Is common.

Preferably, a carbonyl obtained by copolymerizing vinyl monomers (a) to (d) in the following ratio to give an aqueous copolymer dispersion which is a precursor before being reacted with the hydrazine hydrate of the component (A). A group-containing copolymer aqueous dispersion is preferred.

(A) vinyl monomer 0 to 75% by weight, preferably 20 to 70% by weight (b) vinyl monomer 25 to 99.5% by weight, preferably 30 to 80% by weight (c) carbonyl group-containing unit Monomer 0.5 to 60% by weight, preferably 1 to 20% by weight (d) Vinyl monomer 0 to 10% by weight, preferably 0.5 to 5% by weight If necessary, vinyl unit amount of these (a) to (d) 0-40% by weight of acrylonitrile and methacrylonitrile or / and mono-olefinic unsaturated sulfonic acid
Add an amount of 10% by weight or less, so that the film-forming temperature (MFT) of the copolymer aqueous dispersion obtained by emulsion polymerization is 60 ° C or less,
Determine the type and amount of each vinyl monomer.

(Resin Aqueous Dispersion Composition) The resin aqueous dispersion of the component (A) and the copolymer aqueous dispersion of the component (B) have a carbonyl group (> C = 0) of the component (B).
(A) with respect to 1 equivalent of the carbonyl group of the copolymer having
Acrylic copolymer hydrazine residue (-NH ・ NH
₂ ) is mixed so that it becomes 0.05 to 5 equivalents.

The composition of the present invention may further contain an aqueous dispersion of another resin, an inorganic filler, a pigment, cement, a solvent, a viscosity modifier, and the like.

The composition of the present invention is useful as a mastic material, a general coating material, a floor or roof coating material, a paper, a waterproofing material for fibers, an adhesive, an emulsion for polymer cement and the like.

Hereinafter, the present invention will be described in more detail with reference to Examples. The parts and% in the examples are by weight unless otherwise specified.

Production Example of Aqueous Dispersion Example 1 Component (B): Temperature controller, anchor type stirrer, reflux condenser, supply container,
The following raw materials were charged into a reaction vessel equipped with a thermometer and a nitrogen introducing tube.

180 parts of water 35% aqueous solution of sodium salt of sulfuric acid half ester of p-nonylphenol (anionic emulsifier) reacted with 20 mol of ethylene oxide 5 parts of p-nonylphenol (nonionic emulsifier) reacted with 25 mol of ethylene oxide 20 parts of 20% solution.

The following mixtures were used as feed I.

Water 200 parts 35% solution of the anionic emulsifier 25 parts Styrene 242 parts n-Butyl acrylate 215 parts Acrylic acid 10 parts Acrolein 11 parts Acrylamide 10 parts As feed II, a solution of 2.5 parts potassium persulfate in 85 parts water Was prepared.

After replacing the inside of the reactor with nitrogen gas, feed
10% was added and the mixture was heated to 90 ° C. Then supplies
10% of II was injected into the reactor, and then the remaining feeds I and II were fed to the reactor in a uniform and parallel manner over 3 to 3.5 hours. After feeding, the mixture was kept at 90 ° C. for 1.5 hours to carry out emulsion polymerization, and then ammonia water (28%) was added to adjust the PH to 8 to obtain an aqueous dispersion of the copolymer.

Examples 2 to 3 The copolymer composition of Example 1 was changed to the ratio shown in Table 1, and the same polymerization operation as in Example 1 was performed to obtain an aqueous dispersion.

Example 4 [Production Example of Aqueous Carbonyl Group-Containing Polymer Solution] 300 g of water was placed in a reaction vessel equipped with a temperature controller, an anchor type stirrer, a reflux condenser, a thermometer and a nitrogen inlet tube, while introducing nitrogen gas. Kept at ℃. The following feed 1 and feed 2 were uniformly added into this reaction vessel over 3 hours, and after the addition was completed, the mixture was reacted at 90 ° C. for another 1 hour to prepare an aqueous solution of a carbonyl group-containing polymer (solid content: 27% by weight). ) Got.

The solubility of this polymer in 100 g of water was 35 g or more, and the number average molecular weight of the polymer was about 25,000.

Examples 5 to 7 [Production Example of Component (A)] Hydrazine hydrate (100%) was added to 1,000 parts of each of the aqueous dispersions of the copolymer having a solid content of 50% obtained in Production Examples 1 to 3.
Was added thereto, and the mixture was stirred and reacted at 90 ° C. for 5 hours to obtain an aqueous dispersion of a hydrazine-modified copolymer. It was confirmed by gas chromatographic analysis that hydrazine was almost completely reacted.

Example 8 [Production Example of Aqueous Polymer Solution Containing Hydrazine Group] In a reaction vessel equipped with a temperature controller, an anchor type stirrer, a reflux condenser, a thermometer, and a nitrogen inlet tube, 300 g of an aqueous polyacrylamide solution (molecular weight 30,000 to 40,000 20% aqueous solution) 600 g (80% aqueous solution) of hydrazine hydrate aqueous solution was added and reacted at 70 ° C for about 10 hours while stirring. Then, the above reaction product was slowly added to 10 methanol with stirring. The resulting precipitate was purified by the reprecipitation method to obtain a water-soluble acid hydrazide polymer. This polymer was measured by the iodometric titration method,
The hydrazide group content was 75 mol%.

Table 1 shows the resin raw materials used in the production of the polymers or oligomers of Production Examples 1 to 7 and the properties of the obtained polymers or oligomers.

The abbreviations in the table are as follows.

SM: Styrene A / nB: n-butyl acrylate ACL: Acrolein AA: Acrylic acid A / Amid: Acrylamide 2-EHA: 2-Ethylhexyl acrylate EA: Ethyl acrylate MMA: Methyl methacrylate DA / AAmid: Diacetone acrylamide Example 9 [ Production example of polyhydrazide] 200 m equipped with a thermometer, stirrer, and Friedrich condenser
Into a 4-neck flask of l, ethyl acrylate oligomer (M
(W = 2930, manufactured by Toagosei Co., Ltd.) 20 g and 64% hydrazine hydrate (0.6 mol) 19.2 g were charged. The mixture was then heated to 95 ° C. for 1.5 hours under a nitrogen atmosphere to give the polyhydrazide.

Example 1 Aqueous dispersion 100 of the hydrazine-modified copolymer obtained in Production Example 5
To 200 parts, 200 parts of the carbonyl group-containing copolymer aqueous dispersion obtained in Production Example 7 was added, and mixed by stirring to obtain a copolymer aqueous dispersion composition.

This composition was used as a paint and evaluated by the following methods.

The results are shown in Table 2.

(1) Water resistance test A paint is applied to a flexible plate (7.5 cm in length, 15 cm in width, 0.5 cm in thickness, 0.5 cm) defined in JIS A-5403 (asbestos slate) so that a 50 μm thick coating film can be obtained, A test piece was prepared by drying at 20 ° C. for 1 week.

The test piece was immersed in water at 40 ° C., and the appearance of the coating film and the presence or absence of blister formation were evaluated after 2 days and 1 week.

(2) Anticorrosion test A coating was applied on a mild steel plate so as to obtain a coating having a thickness of 50 µm, and dried at 20 ° C for 1 week to prepare a test piece. This test piece was dipped in a 3% saline solution, and the state of rust generation after 1 day and 2 days was visually evaluated and evaluated.

(3) Adhesion Test A paint was applied on the alkyd resin coating film so that a coating film having a thickness of 50 μm was obtained, and dried at 20 ° C. for one week. The obtained coating film was subjected to a peeling test using an adhesive tape [Cellophane tape (trade name) manufactured by Nichiban Co., Ltd.], and the adhesive strength at that time was evaluated.

(4) Evaluation Criteria Evaluation was based on the following criteria.

A: Very good B: Good C: Normal D: Poor Examples 2-4, Comparative Examples 1-6 A coating material having the composition shown in Table 2 was prepared, and this coating material was obtained in the same manner as in Example 1. The obtained coating film was evaluated.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Takeo Tsukamoto, Inventor, 1000 No. 1000, Kawajiri-cho, Yokkaichi-shi, Mie Mitsubishi Petrochemical Verditsie Co., Ltd. (56) Reference JP-A-55-147562 (JP, A) JP-A-58 -96643 (JP, A) JP 60-38468 (JP, A) JP 62-62852 (JP, A)

Claims (1)

[Claims] 1. A hydrazine residue obtained by reacting (A) an aqueous dispersion of an acrylic copolymer having an amide group and / or an ester group with hydrazine hydrate.
An acrylic copolymer aqueous dispersion having at least one, (B)
The carbonyl group-containing copolymer aqueous dispersion is used so that the hydrazine residue of the acrylic copolymer of the component (A) is 0.05 to 5 molar equivalents to 1 equivalent of the carbonyl group of the copolymer of the component (B). A self-crosslinking resin aqueous dispersion composition obtained by mixing with.