JPS5928202B2 - Method for producing vinyl polymer emulsion using fatty acid-modified epoxy resin as emulsifier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing an oxidation-curable vinyl polymer emulsion, more specifically, a method for producing an oxidation-curable vinyl polymer emulsion, using a high-molecular-weight, oxidation-curable resin as an emulsifier, and having a Q value of at least 0.1 in terms of Q and e theory. The present invention relates to a method for producing an oxidation-curable vinyl polymer emulsion obtained by emulsion polymerization of polymerizable vinyl monomers.

Conventionally, various attempts have been made to obtain oxidation-curable vinyl polymer emulsions by using high-molecular weight, oxidation-curable resins as emulsifiers in emulsion polymerization. For example, emulsions using maleated polybutadiene, maleated oil, and alkyd resins as emulsifiers are known. However, these emulsions have the following drawbacks. That is, vinyl polymer emulsions obtained using maleated 1.4-type polybutadiene as an emulsifier have poor J weather resistance due to too many double bonds in the emulsifier and are susceptible to deterioration by ultraviolet rays. Emulsions obtained by using maleated 1,2-type polybutadiene as an emulsifier have extremely high crosslinking properties, and the particles are made up of macromolecules, so there is no problem with fusion between particles during curing and drying. Moreover, the drying time was too fast, which caused problems in painting workability. Furthermore, since the maleated oil has a low molecular weight, emulsions using maleated oil contain many non-maleated molecules and lack emulsifying ability and drying properties. Emulzoyon, which uses alkyd resins as emulsifying agents, has poor compatibility between the emulsifier and the polymerizable vinyl monomer that undergoes emulsion polymerization, and the carboxyl group is not placed in the appropriate position to form an emulsion. Because the polymerization chain-terminating unsaturated bonds (drying oil fatty acid groups or "5" are semi-drying oil fatty acid groups) are mixed roughly, emulsion formation and polymerization do not proceed easily, and fine oxidation hardening occurs. The present inventors have conducted extensive research in order to obtain an excellent oxidation-curing vinyl polymer emulsion that overcomes the above-mentioned drawbacks of conventional emulsions. As a result, we have completed the present invention.

That is, the present invention has Q. When producing an emulsion of a vinyl polymer by emulsion polymerization of a polymerizable vinyl monomer having a Q value of at least 0.1 as determined by the E theory, drying oil fatty acids and/or semi-drying oil fatty acids are added to epoxy resins. A fatty acid-modified epoxy resin obtained by addition reaction is maleated or partially maleated, and then neutralized, and the resulting water-soluble product is used as an emulsifier, and the acid value in the total solid content of the produced emulsion before neutralization is about 3 to The present invention relates to a method for producing a vinyl polymer emulsion, characterized in that emulsion polymerization is carried out using the vinyl polymer emulsion at a ratio of 150%. The emulsifier used in the present invention has a high molecular weight and has a structure suitable as an emulsifier for emulsion polymerization of polymerizable vinyl monomers as shown below.

That is, the emulsifier of the present invention is a resin whose main chain is suitably lipophilic, and whose side chain is a maleated drying oil or semi-drying oil fatty acid group. This side chain and the main chain are connected by an ester bond between a carboxyl group from the side chain and an epoxy group from the main chain. Such a structure in which fatty acid groups are concentrated is suitable for emulsification, and furthermore, when a carboxylic acid group is introduced into a highly oily group such as a fatty acid group by maleation, this will cause the interaction with water on the particle surface to increase. It makes the interface smooth and makes it easy to form a stable emulsion. Furthermore, such a carboxylic acid group has excellent storage stability, unlike the case where a polybasic acid compound is introduced into an epoxy resin through an ester bond. When a polymerizable vinyl monomer is added to an aqueous solution of this emulsifier and stirred, this vinyl monomer is well compatible with the main chain, which is rich in lipophilicity, and is incompatible with the water-soluble carboxylic acid group and is separated from it. It becomes an emulsion.

The polymerizable vinyl monomer is located inside the emulsion particles, and the drying oil fatty acid or semi-drying oil fatty acid portion is appropriately located in the outer shell of the emulsion particle, so that it is not included in the drying oil fatty acid or semi-drying oil fatty acid in the outer shell. The chain transfer type double bonds in the drying oil fatty acid or semi-drying oil fatty acid are less likely to inhibit emulsion polymerization, and on the other hand, the active sites for oxidative curing in the drying oil fatty acid or semi-drying oil fatty acid are less likely to be destroyed by radical polymerization. Furthermore, unlike the case where maleated polybutadiene is used, the absolute number of carbon-carbon double bonds is small (however, the activity is strong), so it has excellent weather resistance.
In addition, since the inside of the emulsion has a moderately low molecular weight compared to 1,2-vinyl polybutadiene, it has good coating workability, and crosslinking after film formation is quick, improving the physical properties and weather resistance of the coating film. Also good. The epoxy resin used in the present invention is as follows.

For example, a reaction product of epichlorohydrin and/or methylepichlorohydrin, bisphenol A1, bisphenol A and dicarboxylic acid, halogenated bisphenol, bisphenol F1 resorcinol, tetrahydroxyphenylmethane, polyhydric carboxylic acid, novolak resin, polyalcohol, Reactants with polyglycols, glycerin, etc.
Polyolefin-type epoxy resins, epoxidized oils, and alicyclic epoxies such as vinylcyclohexene dioxide, synchlopentane edge oxide, and 3,4-epoxy-16-methylcyclohexylmethyl-3,4-epoxy-6-methylcyclohexanecarboxylate. Such as resin. Typical examples include Epicort resin (manufactured by Ciel Chemical, trade name) and Epiclon resin (manufactured by Dainippon Ink, trade name). These resins used have a number average molecular weight of about 150 to 7,000. In addition, the amount of drying oil fatty acid and/or semi-drying oil fatty acid to be used needs to be about 20 to 85 in fatty acid oil length, preferably about 30 to 85, in order to fix and stabilize the emulsion particles.
0 is better.

Examples of fatty acids include safflower oil fatty acids, soybean oil fatty acids, linseed oil fatty acids, hempseed oil fatty acids, poppy oil fatty acids,
Particularly preferred are those containing many non-conjugated double bonds such as sunflower oil fatty acids and walnut oil fatty acids, which allow maleation and polymerization reactions to occur without gelation and have good curability, such as corn oil fatty acids, cottonseed oil fatty acids, and chikara oil. fatty acid,
Oiticica oil fatty acid, peanut oil fatty acid, eno oil fatty acid,
Poppy oil fatty acids, rubber seed oil fatty acids, sesame oil fatty acids, tall oil fatty acids, tung oil fatty acids, dehydrated castor oil fatty acids, high diene fatty acids (manufactured by Soken Kagaku Co., Ltd., synthetic fatty acids containing a large amount of conjugated diene), etc. can also be used. The emulsifier of the present invention comprises drying oil fatty acid residues and/or
Or after maleating or partially maleating a fatty acid-modified epoxy resin having a semi-drying oil fatty acid residue as a side chain,
Obtained by neutralization and water solubilization. Maleation may be carried out by a conventional method, and maleic acid, maleic anhydride or fumaric acid may be reacted at about 50 to 250°C. In particular, when many hydroxyl groups remain in the polymer, it is preferable to esterify with a low-molecular or high-molecular acid such as acetic acid, propionic acid, or stearic acid to remove excess hydroxyl groups, and then maleate the polymer. Maleation with maleic anhydride requires ring opening of the acid anhydride group, which can be carried out with water, alcohol, ammonia, amine, etc., and the final acid number before neutralization is preferably about 20 to 350. , particularly preferably about 50 to 150. When maleating with maleic acid, it is preferable to adjust the amount of maleic acid so that the acid value before neutralization falls within the above range. When the acid value is in the above range of about 20 to 350, the maleated or partially maleated product is water-soluble,
It has good water dispersibility and the resulting coating film also has excellent water resistance. Neutralization may be carried out by any known method, for example, using ammonia, amines, alkali metal compounds, etc. The emulsion composition of the present invention is obtained by polymerizing a polymerizable vinyl monomer into an emulsion using the emulsifier obtained as described above.

A wide variety of polymerizable vinyl monomers can be used as the polymerizable vinyl monomer in the present invention, but it is not preferable to use a large amount of a highly hydrophilic monomer as in the case of general emulsion polymerization. Examples of such polymerizable vinyl monomers include Q, . For example, the Q value determined by the theory of e is at least 0.1 = general formula (where R1 is hydrogen or a methyl group, when R1 is hydrogen, R2 is an alkyl group having 2 to 26 carbon atoms, and when R1 is a methyl group, R2 represents an alkyl group having 1 to 26 carbon atoms), glycidyl methacrylate, glycidyl acrylate, adducts of glycidyl methacrylate or glycidyl acrylate with carboxylic acids having 1 to 26 carbon atoms, ethylene Esterified product of glycol monoalkyl ether, propylene glycol monoalkyl ether or diethylene glycol monoalkyl ether (alkyl group has 1 to 8 carbon atoms) and acrylic acid or methacrylic acid, allyl acrylate, allyl methacrylate, 2-
Hydroxypropyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl methacrylate, acrylic acid or methacrylic acid and Cardilla E (
(manufactured by Ciel Chemical Co., Ltd., trade name), diethylaminoethyl methacrylate, allyloxyethyl acrylate, allyloxyethyl methacrylate, styrene, vinyltoluene, α-methylstyrene, butadiene,
Examples include pentadiene, isoprene, chloroprene, and methacrylonitrile. These polymerizable vinyl monomers may be used alone or in combination of two or more, and furthermore, the vinyl monomers may contain acrylic acid, methacrylic acid, itaconic acid, acrylamide, methacrylamide, N-methyl in an amount of about 20% by weight or less. Water-soluble or hydrophilic vinyl monomers such as acrylamide, N-ethyl acrylamide, dimethylaminoethyl methacrylate, N-methylol acrylamide, N-methylol methacrylamide, hydroxyethyl acrylate, vinyl pyridine, acrylonitrile, methyl acrylate, vinyl pyrrolidone, and acrolein, etc. May be used together. The ratio of the emulsifier and these polymerizable vinyl monomers used in the present invention is such that the acid value in the total solid content of the produced emulsion before neutralization is preferably about 3 to 150, more preferably about 15 to 150.
It is desirable to set the value to 50.

However, if acrylic acid or methacrylic acid is added as a monomer, the acid value of these acids shall not be taken into account. Further, the solid content concentration of the emulsion composition is about 15 to
65% is preferred. As the emulsion polymerization method for obtaining the emulsion composition of the present invention, commonly known methods can be used.

Polymerization is often carried out with stirring, but it is also possible to leave the monomer in an emulsion state after stirring. Although a polymerization initiator is not necessarily required, it may be added in a conventional manner to speed up the polymerization. Any initiator may be used as long as it generates radicals, and peroxide-azo initiators are generally used. The emulsion obtained according to the present invention is used as a cold-curing type coating forming agent, but it can also be used as a bake-drying type coating forming agent.

It can also be used in a wide range of other applications such as resin processing agents. Although the emulsion of the present invention exhibits excellent performance by itself, it may be used in combination with other water-soluble resins to further improve performance. Next, the present invention will be explained in more detail with reference to Examples and Comparative Examples.

In addition, unless otherwise specified, parts and percentages used below are as follows:
Please indicate weight parts and weight %. Example 1 In a reaction vessel, 1000 parts of Epicote 1001 (manufactured by Ciel Chemical, trade name), 1866 parts of linseed oil fatty acid, 1 part of sodium benzoate, 6 parts of dibutyltin oxide, and 15 parts of toluene were added.
0 parts was added and reacted at 240° C. for 12 hours under nitrogen flow.

An adduct with an acid value of 5.0 was obtained. The solids content was 92%. 1320 parts of the above adduct, 170 parts of maleic anhydride, and 25 parts of xylene were placed in a reaction vessel, and the mixture was heated under nitrogen flow for 18 parts.
The reaction was carried out at 0°C for 3 hours.

A maleated resin having a total acid value of 102 was obtained. Put 160 parts of the above maleated resin, 56 parts of n-butyl cellosolve, 757 parts of water, and 28 parts of triethylamine into a reaction container,
Stirring was continued for approximately 40 minutes until the maleated resin was completely dissolved in the water.

Next, 1 part of ammonium persulfate was dissolved in 20 parts of water and added to the reaction vessel. After stirring for about 3 minutes at room temperature, a mixture of 406 parts of n-butyl methacrylate and 8 parts of 1,6-hexanediol diacrylate was added to the reaction vessel. The mixture was stirred at room temperature for about 40 minutes, and the temperature was gradually raised under nitrogen flow. Fever started at about 70°C. After generating heat, the reaction was carried out at 80° C. for 2 hours to obtain an emulsion. Example 2 160 parts of the maleated resin obtained in Example 1, 56 parts of n-butyl cellosolve, 769 parts of water, and 16.2 parts of aqueous ammonia (29% aqueous solution) were placed in a reaction vessel, and the maleated resin was completely dissolved in the water. The mixture was stirred for about 40 minutes.

Next, 1 part of ammonium persulfate was dissolved in 20 parts of water, added to the reaction vessel, and stirred for 2 minutes.
of the mixture was added. Stirred for about 20 minutes. The temperature was gradually increased under nitrogen flow. Exotherm started at about 68°C, and after the exotherm, the reaction was carried out at 80°C for 2 hours to obtain an emulsion. Example 3 160 parts of the maleated resin obtained in Example 1, 56 parts of n-butyl cellosolve, 769 parts of water, and 16.2 parts of aqueous ammonia (29% aqueous solution) were placed in a reaction vessel, and the maleated resin was completely dissolved in the water. The mixture was stirred for about 40 minutes.

Next, 1 part of ammonium persulfate was dissolved in 20 parts of water and added to the reaction vessel. After stirring for about 2 minutes, 203 parts of styrene, n-
A mixture of 203 parts of butyl methacrylate, 8 parts of 1,6-hexanediol diacrylate, and 203 parts of styrene was added to the reaction vessel. The mixture was stirred for about 30 minutes under nitrogen flow, and the temperature was gradually raised. Fever started at about 67°C.
After generating heat, the reaction was carried out at 80° C. for 2 hours to obtain an emulsion. Example 4 160 parts of the maleated resin obtained in Example 1, 56 parts of n-butyl cellosolve, 769 parts of water, and 16.2 parts of aqueous ammonia (29% aqueous solution) were placed in a reaction vessel, and the maleated resin was completely submerged in water. Stir for approximately 40 minutes until dissolved.

Next, 1 part of ammonium persulfate was completely dissolved in 20 parts of water and added to the reaction vessel. After 1 minute, 203 parts of styrene, 2-
A mixture of 203 parts of ethylhexyl acrylate and 8 parts of 1,6-hexanediol diacrylate was added to the reaction vessel.

The mixture was stirred and heated for about 20 minutes under nitrogen flow. Approximately 68
Fever started at ℃. After generating heat, the reaction was carried out at 80° C. for 2 hours to obtain an emulsion. Example 5 1320 parts of the adduct obtained in Example 1 (solid content 92%),
130 parts of maleic anhydride and 25 parts of toluene were placed in a reaction vessel and reacted at 180° C. for 3 hours under nitrogen flow.

A maleated resin having a total acid value of 92 was obtained. 160 parts of the above maleated resin, 56 parts of n-butyl cellosolve, 7 parts of water
71 parts and 14.6 parts of aqueous ammonia (29% aqueous solution) were added to the reaction vessel, and stirred for about 50 minutes until the maleated resin was completely dissolved in the water.

Next, 1 part of ammonium persulfate was completely dissolved in 20 parts of water and added to the reaction vessel. 2 minutes later n-butyl methacrylate 4
06 parts of 1,6-hexanediol diacrylate and 8 parts of 1,6-hexanediol diacrylate were added thereto, and the mixture was stirred for about 20 minutes.

It was gradually heated under nitrogen flow, and exotherm started at about 70°C. After generating heat, the reaction was carried out at 80° C. for 2 hours to obtain an emulsion. Comparative Example 1 Maleated 1. with a number average molecular weight of about 3000 and an acid value of 100.
216 parts of an n-butyl cellosolve solution of 2-vinyl type polyptadiene with a solid content of 74% is neutralized with 0.95 equivalents of ammonia and dissolved in 780 parts of water.

After adding 414 parts of n-butyl methacrylate and stirring well to form an emulsion, 1'it of ammonium persulfate dissolved in 20 parts of water was added and heated to 80°C.
Leave for 2 hours to obtain an emulsion. Comparative Example 2 1,367 parts of linseed oil, 132 parts of maleic anhydride, and a small amount of toluene were placed in a 21 quart flask and reacted at 200° C. for 4 hours to obtain maleated linseed oil with an acid value of 88.

Put 160 parts of this into a 21 quart flask, neutralize it with an equivalent amount of aqueous ammonia, and add a small amount of n-butyl cellosolve (so that 3.8% of the total is finally n-butyl cellosolve). This was thoroughly dissolved in 780 parts of water, and 414 parts of n-butyl methacrylate was added thereto while stirring to form an emulsion. A solution of 1 part of ammonium persulfate dissolved in 20 parts of water is added to this and heated to 80>C, and maintained at this temperature for 2 hours to obtain an emulsion. Comparative Example 3 1200 parts of Epon 1001 (manufactured by Ciel Chemical Co., Ltd.), 800 parts of linseed oil fatty acid, and 100 parts of xylene were placed in a reaction container.
The reaction was carried out at 230°C for 6 hours under nitrogen flow, and the resin acid value was reduced to 2.
．． I made it 2.

Once cooled to 100°C, 225 parts of succinic anhydride was added,
The mixture was heated again and reacted at 150°C for 2 hours.

A resin having an acid value of 60 was obtained. 160 parts of the above reactant, n
-Butel 56 parts of cellosolve, 768 parts of water, and 17 parts of triethylamine were placed in a reaction vessel and stirred at room temperature for about 1 hour.

Next, 1 part of ammonium persulfate was dissolved in 20 parts of water and added to the reaction vessel. After 1 minute, add 40 liters of n-butyl methacrylate.
A mixture of 6 parts and 8 parts of 1.6-hexanediol diacrylate was added to the reaction vessel and heated at room temperature for about 20 minutes under nitrogen flow.
The mixture was stirred for a minute.

Claims (1)

[Claims] 1 When manufacturing a vinyl polymer emulsion by emulsion polymerizing a polymerizable vinyl monomer with a Q value determined by the Q, e theory of at least 0.1, drying oil fatty acids and/or semi-drying oil fatty acids are used. A fatty acid-modified epoxy resin obtained by addition reaction to an epoxy resin is maleated,
Then, the water-soluble product obtained by neutralization is used as an emulsifier, and the acid value in the total solid content of the resulting emulsion before neutralization is about 3.
1. A method for producing a vinyl polymer emulsion, which comprises carrying out emulsion polymerization using a vinyl polymer emulsion at a ratio of 150 to 150.