JPH0371448B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION This invention relates to a process for making non-aqueous dispersions of polymers that form coatings of superior performance. As is well known, the non-aqueous dispersion mentioned here refers to a polymer part (solvated part) that is solvated in the organic liquid and the above-mentioned polymer in an organic liquid that does not dissolve the produced polymer (dispersed polymer). It is a dispersion of a produced polymer in which a block or graft polymer having an affinity polymer moiety (produced polymer affinity moiety) is used as a dispersion stabilizer. One of the methods for producing such a dispersion is as follows.
A monomer is polymerized in an organic liquid containing an unsaturated group-containing compound that will serve as a solvation moiety to form a dispersed polymer, and at the same time, a portion of the monomer is added to the above compound as a block or This is a method of dispersing the produced polymer in an organic liquid by graft polymerizing to produce a dispersion stabilizer that is an affinity moiety for the produced polymer. Well-known compounds that can be used in this method include natural rubber, butadiene copolymers,
There are drying oils, drying oil-modified alkyd resins, unsaturated polyester resins, etc. However, when these compounds are used, there are various drawbacks as described below. It is well known that the polarity of the solvated moiety and the resulting polymer are essentially different, but because of this, the two lack compatibility, so it is difficult to obtain a transparent coating film from a dispersion prepared by conventional methods. It was difficult to obtain, and this had a negative effect on gloss, luster, etc. In addition, the solvated portion of the dispersion stabilizer located on the outer surface of each dispersed particle in the dispersion tends to be located on the surface of the coated surface in the coating film, so if the proportion of the solvated portion is small. However, since these properties have a great influence on the performance of the coating film, coating films obtained from conventional dispersions containing the above-mentioned compounds as solvated moieties have the disadvantage that the inherent drawbacks of these compounds are greatly manifested. In other words, the cured coating film tends to yellow and suffers from poor weather resistance, acid resistance, drying properties, etc. As a result, there is a drawback that the excellent performance of the produced polymer itself, which is the main component of the dispersion liquid, cannot be fully utilized in the coating film.Moreover, the better the stability of the dispersion liquid, the more the shape of the dispersed particles remains in the coating film. , the above-mentioned tendency becomes more noticeable, and the above-mentioned drawbacks become more noticeable.
Furthermore, the higher the proportion of the solvated moiety, the more pronounced the same drawback becomes. Therefore, the dispersion prepared by the conventional method was unsuitable for use in exterior packaging. In view of these points, the present inventors have made extensive studies and found that fatty acids and/or fatty acids having an unsaturated double bond are used as compounds to be solvated moieties.
Alternatively, the inventors have discovered that the various drawbacks of the above-mentioned prior art can be successfully overcome by using a specific vinyl polymer in which a glycidyl ester of a fatty acid is introduced through an ester bond and modified with the compound. , we have completed the present invention. That is, the present invention comprises (1) an organic liquid, (2) acrylic acid or methacrylic acid, and other vinyl that can be dissolved or swelled in the organic liquid 1 and copolymerized with the following vinyl monomer 3. 90~ with system monomer
20% by weight and 10 to 80 glycidyl esters of fatty acids with 8 or more carbon atoms and unsaturated double bonds.
Vinyl polymer 2 having a copolymerizable unsaturated double bond into which the glycidyl ester of the fatty acid is introduced via an ester bond, or (methyl) of acrylic acid or methacrylic acid, obtained by reaction with % by weight 90 to 20% by weight of glycidyl ester and other vinyl monomers, and 10 to 80% of fatty acids having 8 or more carbon atoms and having unsaturated double bonds.
Before polymerization, the fatty acid is dissolved in the organic liquid 1 in the presence of a vinyl polymer 2 having a copolymerizable unsaturated double bond introduced by an ester bond, obtained by reaction with % by weight. However, the present invention provides a method for producing a non-aqueous polymer dispersion, which comprises copolymerizing a vinyl monomer 3 which is no longer soluble in the organic liquid 1 after polymerization. The coating film obtained from the dispersion according to the method of the present invention is not modified with fatty acids having an unsaturated double bond and having 8 or more carbon atoms (hereinafter abbreviated as fatty acids) and/or glycidyl esters of fatty acids. Compared to those using vinyl polymers (hereinafter abbreviated as acrylic polymers), they have excellent transparency, drying properties, and solvent resistance. Moreover, since an acrylic polymer is used as the compound that becomes the solvation part, the resulting coating film has both the excellent properties inherent to acrylic polymers and the excellent properties inherent to the resulting polymer. It will have excellent performance. That is, a coating film with little coloration and excellent weather resistance, solvent resistance, chemical resistance, impact resistance, hardness, etc. can be obtained. Even if the dispersion liquid is stable or the proportion of the solvated portion is high, these excellent effects are not impaired in any way, but may even be enhanced. Therefore, the present invention can be said to be extremely useful because the dispersion according to the present invention can be fully used in the field of room temperature drying paints, which has been difficult to apply in the past. The organic liquid referred to here is non-polar or has relatively low dissolving power, and does not dissolve the vinyl monomer-forming polymer described below, but dissolves or swells the acrylic polymer described below, and is non-polar. It is polymerizable. Examples of such organic liquids include hexane,
Aliphatic hydrocarbons such as heptane, octane, etc.;
Boiling points such as petroleum benzene, ligroin, mineral spirits, petroleum naphtha, kerosene, etc.
Hydrocarbon mixtures at 300°C; alicyclic hydrocarbons such as cyclohexane, methylcyclohexane, ethylcyclohexane, etc.; and mixtures thereof. In some cases, it may contain up to about 50% by weight (hereinafter referred to as %) or more of aromatic hydrocarbons or polar solvents such as alcohols, esters, ethers, and ketones. The appropriate amount of these organic liquids to be used is such that the solid content of the dispersion is 30 to 70%, more preferably 40 to 60%. The vinyl monomers polymerized in these organic liquids produce polymers that do not dissolve in the organic liquids (dispersion polymers), as well as block or graft polymers with the acrylic polymer as the solvation part (dispersion stabilizer). ). The term "does not dissolve" here means that a polymer with an average molecular weight or more is not dissolved, but does not mean that a polymer with an average molecular weight or less, which is inevitably produced as a by-product in a polymerization reaction, does not dissolve. Used in carrying out the method of the present invention,
The vinyl polymer 2 contains 90 to 20% by weight of acrylic acid or methacrylic acid and other vinyl monomers, and a glycidyl ester of a fatty acid having 8 or more carbon atoms and having an unsaturated double bond. The glycidyl ester of the above fatty acid obtained by reaction with 10 to 80% by weight of acrylic acid or methacrylic acid has a copolymerizable unsaturated double bond introduced by an ester bond, or Obtained by the reaction of 90 to 20% by weight of methyl) glycidyl ester and other vinyl monomers with 10 to 80% by weight of a fatty acid having 8 or more carbon atoms and having an unsaturated double bond. The above-mentioned fatty acid has a copolymerizable unsaturated double bond introduced by an ester bond, such as acrylic acid or methacrylic acid; (methyl)glycidyl ester of acrylic acid or methacrylic acid; or other vinyl monomers. Methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, iso-propyl (meth)acrylate, to exemplify only particularly representative examples. , n-butyl (meth)acrylate, iso-butyl (meth)acrylate, tert-butyl (meth)acrylate, sec-butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate ,
Lauryl (meth)acrylate, Benzyl (meth)acrylate, 2-Hydoxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, Glycidyl (meth)acrylate, Methylglycidyl (meth)acrylate, (Meth) ) Acrylic esters such as dimethylaminoethyl acrylate,
Examples include (meth)acrylic acid, and others include styrene, (anhydrous) maleic acid, fumaric acid,
Crotonic acid, itaconic acid, dodecynylsuccinic anhydride, monobutyl fumarate (meth)acrylamide, N-methylol (meth)acrylamide,
N-methoxymethyl (meth)acrylamide,
Diacetone acrylamide, (meth)acrylonitrile, dibutyl fumarate, vinyl chloride, vinylidene chloride, vinyl acetate, vinyl propionate,
Other monomers other than the above-mentioned acrylic monomers, such as allyl glycidyl ether, vinyltoluene, α-methylstyrene, etc., can be used in combination. The vinyl polymer 2 used in the present invention is
Of these, 10 to 80% by weight is occupied by fatty acids and/or glycidyl esters of fatty acids having unsaturated double bonds, as described below, and the remaining 90 to 20% by weight is composed of carboxyl groups and/or glycidyl groups. The containing acrylic monomer, or the monomer and the vinyl monomer other than the monomer, respectively,
It can be obtained by occupying the
It is a polymer obtained by using vinyl monomer 3, which dissolves or swells in an organic liquid that does not dissolve the produced polymer, and which is modified with a fatty acid and/or a glycidyl ester of a fatty acid. The fatty acids used in the present invention are those having 8 or more carbon atoms, such as unsaturated fatty acids such as oleic acid, linoleic acid, linolenic acid, eleostearic acid, ricanic acid, and ricinoleic acid, and tung oil. Drying oil fatty acids such as fatty acids, linseed oil fatty acids, dehydrated castor oil fatty acids, soybean oil fatty acids, tall oil fatty acids, cottonseed oil fatty acids; semi-drying oil fatty acids such as olive oil fatty acids, rice bran fatty acids, castor oil fatty acids, coconut oil fatty acids, hydrogenated coconut oil fatty acids Examples include non-drying oil fatty acids such as oil fatty acids and palm oil fatty acids. Further, examples of the glycidyl ester of fatty acid include the glycidyl esters of each fatty acid described above. In addition, the acrylic polymer in the present invention is, for example,
() Those synthesized by the reaction of mutual unsaturated bonds between drying oil fatty acids and/or semi-drying oil fatty acids or their glycidyl esters and carboxyl group- and/or glycidyl group-containing acrylic monomers, () Hydroxyl group-containing acrylic monomers such as 2-hydroxyethyl meth)acrylate and 2-hydroxypropyl (meth)acrylate; and/or glycidyl group-containing acrylic monomers such as glycidyl (meth)acrylate and methylglycidyl (meth)acrylate. Those synthesized from fatty acids and glycidyl group-containing polymers obtained by polymerizing monomers containing monomers, and carboxyl compounds obtained by polymerizing monomers containing (meth)acrylic acid. Those synthesized from group-containing polymers and glycidyl esters of fatty acids, () Acrylic monomers and allyl glycidyl ethers that do not have functional groups that react with fatty acids or glycidyl esters of fatty acids, such as carboxyl groups and glycidyl groups. , (anhydride) maleic acid, fumaric acid, crotonic acid, itaconic acid, dodecynylsuccinic anhydride, monobutyl fumarate, etc., glycidyl groups, carboxyl groups, etc., and other unsaturated groups having functional groups that react with fatty acids or glycidyl esters of fatty acids. These include those synthesized from a polymer with a monomer and a fatty acid or its glycidyl ester. The amount of fatty acids and/or their glycidyl esters used in such an acrylic polymer is determined by the amount of fatty acids and/or their glycidyl esters and each monomer constituting the acrylic polymer 2 (that is, the acrylic monomers mentioned above). 10 to 80%, preferably 20 to 70%, based on the total weight of the acrylic monomer and other monomers copolymerizable with the acrylic monomer, and less than 10% to achieve the object of the present invention. If it exceeds 80%, the acid resistance and solvent resistance of the resulting coating film will decrease. The amount of the carboxyl group-containing monomer or glycidyl group-containing monomer used is preferably 0.8 per equivalent of fatty acid or glycidyl ester of fatty acid, respectively.
The amount is such that it is equal to or more than the equivalent amount. In addition, the acrylic polymer used in the present invention contains an appropriate amount in the molecule so that the resulting polymer copolymerizes with a vinyl monomer that is not soluble in organic liquids to produce a block or graft polymer of the acrylic polymer. It is preferable that the compound contains an unsaturated group (also referred to as an unsaturated bond). The suitable content of saturated groups in such a polymer is 1 per number average molecular weight of 150 to 1,000,000. In order to introduce unsaturated groups into acrylic polymers,
Modify the acrylic polymer using the aforementioned unsaturated fatty acids, dry fatty acids, semi-dry fatty acids, and glycidyl esters of these fatty acids, or use monomers having two or more unsaturated groups. It is obtained by Monomers having two or more unsaturated groups are those that introduce unsaturated groups into acrylic polymers, and include butadiene, isoprene, etc., as well as reactive compounds such as (meth)acrylic acid (methyl)glycidyl. Esters of (meth)acrylic acid, esters of (methyl)glycidyl (meth)acrylate and fumaric acid (molar ratio 1:1),
Examples include esters of (methyl)glucidyl (meth)acrylate and fumaric acid (molar ratio 2:1). The unsaturated group-containing acrylic polymer can be produced by a one-step method in which butadiene or the above reaction compound is copolymerized with other monomers according to a conventional method, or the reaction monomer, which is one of the components of the above reaction compound. After copolymerizing a monomer such as (meth)acrylic acid with another monomer, the other reaction compound such as (meth)
Although it can be produced by a two-step process in which (methyl)glycidyl acrylate is added or condensed, the two-step process is preferable in terms of reaction control when incorporating the reactive compound into an acrylic polymer. Known catalysts can be used for addition or condensation reactions. Regardless of the one-stage or two-stage method, the final acrylic polymer contains unsaturated groups. As described above, the acrylic polymer used in the present invention preferably contains an unsaturated group and has 10 to 80
% of fatty acids and/or glycidyl esters of fatty acids. The amount of such acrylic polymer used is based on the amount of vinyl monomer to be polymerized.
A suitable range is 2 to 400 parts, more preferably 20 to 300 parts per 100 parts by weight (shown below). The acrylic polymer is produced by the Kochi polymerization method, but solution polymerization is particularly preferred. Modification with fatty acids and glycidyl esters of fatty acids leads to carboxyl groups and/or
Alternatively, it can be easily carried out by a known addition or condensation reaction with a vinyl monomer that essentially includes a glycidyl group-containing acrylic monomer. Well-known catalysts can be used for addition or condensation reactions.
Further, such modification can be carried out by reacting it with the above-mentioned functional group-containing monomer in advance, by carrying out the reaction simultaneously with the polymerization reaction of the acrylic polymer, or by carrying out the modification after the completion of the polymerization reaction. As described above, the present invention is achieved by polymerizing vinyl monomers in an organic liquid in the presence of an acrylic polymer. Examples of polymerization initiators that can be used include azo compounds such as azobisisobutyronitrile and peroxides such as benzoyl peroxide. The amount used is suitably 0.1 to 10 parts per 100 parts of vinyl monomer to be polymerized. Further, if necessary, mercaptans such as lauryl mercaptan can be used to adjust the molecular weight. Temperature conditions for polymerization reaction are 50 to 150
℃, preferably 60 to 110℃, and the reaction time is 2 to 40 hours, preferably 4 to 25 hours. As mentioned above, the vinyl monomer reacted in the present invention is one that dissolves in an organic liquid before polymerization, and the product after polymerization does not dissolve in the organic liquid. Examples of such vinyl monomers include the above-mentioned acrylic monomers, styrene, vinyltoluene, α-methylstyrene, (meth)acrylonitrile, and other monomers copolymerizable with each of these monomers. . Among these various vinyl monomers, some of the polymers (homopolymers) obtained from them are soluble in the above-mentioned organic liquid 1, but when such monomers are used, other monomers are required. Used in combination with mercury. In the dispersion thus obtained, the produced polymer is dispersed in an organic liquid using an acrylic polymer block or graft polymer as a dispersion stabilizer. Such a dispersion can be cured alone or by curing with a curing accelerator and/or peroxide at room temperature or at 50°C.
Forms a coating film with excellent performance by baking drying at ~300℃. Examples of hardening accelerators that can be used include metal soaps such as cobalt naphthenate, tertiary amines such as dimethylaniline, alcoholates such as sodium methylate, lauryl mercaptan, and N-ethyl metatoluidine. 0.001 to 3.0% is preferable. Examples of peroxides include benzoyl peroxide, methyl ethyl ketone peroxide, and kyumene hydroperoxide, and the amount used is based on the solid content of the dispersion liquid.
0.001-3.0% is preferred. Furthermore, when the dispersion liquid has a functional group (reactive group) in addition to the unsaturated group (unsaturated bond), it is also possible to use a curing agent reactive with the functional group. When the functional group is a hydroxyl group, for example, amino resin, (block) parisocyanate resin, etc. can be used. Further, when the functional group is a carboxyl group, for example, epoxy resin, methoxymethylated acrylamide resin, etc. can be used, and when the functional group is an epoxy group, for example, adipic acid, polyamide resin, etc. can be used.
Polyester resins, amide groups such as amino resins, isocyanate groups such as polyester resins, methylol groups and alkoxymethyl groups such as amino resins, polyester resins, etc. can be used. The usage forms of these hardening agents are solutions,
Although any of dispersion, powder, or solid form is possible, a solution form is preferable from the viewpoint of low-temperature curing, leveling, gloss, adhesion, etc. The present invention will be explained below based on examples. Example 1 (A) Production of solvated component A reactor equipped with a thermometer, a stirrer and a reflux condenser was charged with 200 parts of tert-butyl perbenzoate butyl acetate and heated to 120°C while blowing _N2 gas. A mixed solution consisting of 20 parts of styrene, 169 parts of glycidyl methacrylate, and 5 parts of azobisisobutyronitrile was added dropwise over 6 hours. After keeping at 120℃ for 6 hours, 311 parts of soybean oil fatty acid, 0.2 parts of hydroquinone, and 0.1 parts of 2-methylimidazole were added, and after keeping at 120℃ for another 12 hours,
Solvate component A was obtained by adding 300 parts of Super VM&P naphtha (low aromatic hydrocarbon solvent, manufactured by Ziel Chemical Co., Ltd.). (B) Dispersion polymerization In a reactor equipped with a thermometer, a stirrer, and a reflux condenser, 1000 parts of solvate component A, Super VM&P naphtha 400, was heated to 80°C while blowing _N2 gas, and 350 parts of methyl methacrylate was added to the acrylic. A mixed solution consisting of ethyl acid 145, methacrylic acid 5, benzoyl peroxide 12.5 and super VM&P naphtha 100 was added dropwise over 3 hours. The mixture was kept at 80° C. for an additional 12 hours to obtain a dispersion with a nonvolatile content of 51.9% and a viscosity (Gardner) of J. Example 2 (B) Dispersion polymerization In a reactor equipped with a thermometer, a stirrer, and a reflux condenser, 1000 parts of solvating component A, Super VM&P naphtha 400, was charged and heated to 80°C while blowing _N2 gas, and methacrylic acid was added. A mixed solution consisting of 100 parts of methyl, 100 parts of acrylonitrile, 295 parts of ethyl acrylate, 5 parts of methacrylic acid, 12.5 parts of benzoyl peroxide, and 100 parts of Super VM&P naphtha was added dropwise over 3 hours. The mixture was maintained at 80° C. for an additional 12 hours to obtain a dispersion with a nonvolatile content of 50.9% and a viscosity (Gardner) of R. Example 3 (A) Production of solvated component In a reactor equipped with a thermometer, a stirrer, and a reflux condenser, 300 g of tert-butyl perbenzoate 3 parts butyl acetate was charged and heated to 120°C while blowing _N2 gas. Then, a mixed solution consisting of 100 parts of styrene, 90 parts of 2-ethylhexyl methacrylate, 114 parts of glycidyl methacrylate, and 7.5 parts of azobisisobutyronitrile was added dropwise over 6 hours. After continuing to hold at 120°C for 6 hours, 196 parts of soybean oil fatty acid, 1 part of methacrylic acid, 0.2 parts of hydroquinone, 0.1 part of 2-methylimidazole were added, and after keeping at 120°C for another 12 hours,
Solvate component B was obtained by adding 200 parts of Super VM&P naphtha. (B) Dispersion polymerization In a reactor equipped with a thermometer, a stirrer, and a reflux condenser, 600 parts of solvated component B, Super VM&P naphtha, 580, and 20% butyl acetate were charged, heated to 80°C while blowing _N2 gas, and methyl methacrylate was added. A mixed solution consisting of 490 parts ethyl acrylate, 203 parts, methacrylic acid, 7 parts, benzoyl peroxide, 17.5 parts, and Super VM&P naphtha, 100 parts, was added dropwise over 3 hours. The temperature was further maintained at 80° C. for 12 hours to obtain a dispersion having a nonvolatile content of 52.6% and a viscosity (Gardner) of E. Example 4 (A) Production of solvated component In a reactor equipped with a thermometer, a stirrer, and a reflux condenser, 200 parts of tert-butyl perbenzoate butyl acetate was charged and heated to 120°C while blowing _N2 gas. A mixed solution consisting of 114 parts of styrene, 86 parts of methacrylic acid, and 5 parts of azobisisobutyronitrile was added dropwise over 6 hours. After the mixture was kept at 120°C for 6 hours, 300 parts of glycidyl oleate, 0.2 parts of hydroquinone, and 0.1 parts of 2-methylimidazole were added, and the mixture was kept at 120°C for another 12 hours.
Solvate component C was obtained by adding 300 parts of Super VM&P naphtha. (B) Dispersion polymerization A dispersion with nonvolatile content of 51.0%, viscosity (Gardner), and Q-R was prepared in the same manner as in Example 1 except that solvate component C was used in place of solvate component A in Example 1. Obtained. Comparative Example 1 In a reactor equipped with a thermometer, a stirrer, and a reflux condenser, 5 parts of tert-butyl perbenzoate, 200 parts of butyl acetate, and 300 parts of super VM&P naphtha were charged and heated to 120°C while blowing _N2 gas, and 100 parts of styrene was added. A mixed solution consisting of 390 parts of 2-ethylhexylic methacrylic acid, 10 parts of methacrylic acid, and 12.5 parts of asobisisobutyronitrile was added dropwise over 6 hours. After the mixture was kept at 120°C for 6 hours, 2 parts of glycidyl methacrylate, 0.2 parts of hydroquinone, and 0.1 parts of triethylamine were added, and the mixture was kept at 120°C for an additional 12 hours to obtain solvate component D. (B) Dispersion polymerization A dispersion with a non-volatile content of 50.8% and a viscosity (cardner) of M-N was prepared in exactly the same manner as in Example 1, except that solvate component D was used in place of solvate component A in Example 1. Obtained. Comparative Example 2 (B) Dispersion Polymerization 714 parts of Betucosol P-470-70X (soybean oil-modified alkyd resin, oil length 65%, manufactured by Dainippon Ink & Chemicals Co., Ltd.) was substituted for the solvation component A of Example 1,
Super VM&P naphtha 200 parts, butyl acetate 86
A dispersion having a nonvolatile content of 51.6% and a viscosity (Gardner) of P-Q was obtained in exactly the same manner as in Example 1, except that 1.5% of the non-volatile content was used. Example 3 (B) Dispersion polymerization Betucosol 1307 (soybean oil modified alkyd resin, oil length 41%,
The dispersion obtained in exactly the same manner as in Example 3 except for using Dainippon Ink & Chemicals Co., Ltd.) had poor stability and separated when left standing. 2% of 6% cobalt naphthenate and 2% of 24% lead naphthenate were added to the solid content of the dispersion liquid of each example except Comparative Example 3, and the mixture was applied to a bonderite-treated mild steel plate using a 6 mm applicator and dried at room temperature. A coating film test was conducted. The results are shown in Table 1. 【table】

Claims (1)

[Claims] 1 Organic liquid 1 and acrylic acid or methacrylic acid and other vinyl monomers that can be dissolved or swelled in the organic liquid 1 and can be copolymerized with vinyl monomer 3 below. The glycidyl ester of the above-mentioned fatty acid is obtained by the reaction of 20% by weight with 10 to 80% by weight of a glycidyl ester of a fatty acid having an unsaturated double bond and having 8 or more carbon atoms, which has been introduced through an ester bond. Copolymerizable unsaturated double bond-containing vinyl polymer 2, or (methyl)glycidyl ester of acrylic acid or methacrylic acid and other vinyl monomers 90 to 20
% by weight, has an unsaturated double bond, and has a carbon number of 8
Before polymerization, in the presence of a copolymerizable unsaturated double-junction-containing vinyl polymer 2 into which the above fatty acid has been introduced through an ester bond, which is obtained by reaction with 10 to 80% by weight of the above fatty acid. A method for producing a non-aqueous polymer dispersion, characterized by copolymerizing a vinyl monomer 3 that dissolves in the organic liquid 1 but no longer dissolves in the organic liquid 1 after polymerization. .