JP3478416B2 - Self-crosslinking resin - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-crosslinking resin having an epoxy group and a carboxyl group by ring opening of a cyclic acid anhydride group in the same molecule.

[0002]

2. Description of the Related Art Cross-linking and curing a resin based on the reaction between an epoxy group and a carboxyl group is widely used as a means for curing a paint film.
For example, there are a mixed type of an epoxy group-containing resin and a carboxyl group-containing resin, or a self-crosslinking type having both the functional groups in the same molecule.

The latter self-crosslinking type resin is prepared, for example, by polymerizing a monomer component containing a glycidyl group-containing polymerizable unsaturated monomer and a carboxyl group-containing polymerizable unsaturated monomer as main components ( See, for example, JP-A-63-135465.

However, in this method, the respective functional groups of the both unsaturated monomers react with each other during or before the polymerization, resulting in gelation or partial polymerization, so that the quality between the production lots may be deteriorated. The variation becomes large, which is not preferable.

[0005]

DISCLOSURE OF THE INVENTION According to the present invention, a self-crosslinking resin having an epoxy group and a carboxyl group in the same molecule is reduced in quality variation without gelling or partially polymerizing. The method is characterized in that a ring-opening half-ester reaction of a cyclic acid anhydride with the hydroxyl group of a compound having a hydroxyl group and an epoxy group in the same molecule, or an epoxy group and a cyclic acid anhydride group in the same molecule is carried out. The cyclic acid anhydride group of the compound of 1) is subjected to a ring-opening half-ester reaction with an alcohol component.

Therefore, the present invention provides: A compound having a hydroxyl group and an epoxy group in the same molecule and having a weight average molecular weight of 500 or more is obtained by subjecting the hydroxyl group to a ring-opening half-ester reaction with a cyclic acid anhydride. 1. A self-crosslinking resin (A) having a carboxyl group and an epoxy group at the same time by a ring, and 2. A cyclic acid in the same molecule, which is obtained by subjecting the cyclic acid anhydride group of a compound having an epoxy group and a cyclic acid anhydride group in the same molecule and having a weight average molecular weight of 500 or more to a ring-opening half-ester reaction with an alcohol component. It is intended to provide a self-crosslinking resin (B) having a carboxyl group and an epoxy group by ring opening of an anhydrous group.

The self-crosslinking resins (A) and (B) provided by the present invention will be described in more detail below.

Self-crosslinking resin (A): A compound (A-1) having a hydroxyl group and an epoxy group in the same molecule and having a weight average molecular weight of 500 or more is used as a starting material.
One or more carboxyl groups and epoxy groups obtained by ring-opening of a cyclic acid anhydride group in the same molecule, which are obtained by subjecting the hydroxyl group of 1) to a ring-opening half-esterification reaction of a cyclic acid anhydride (A-2). It is a self-crosslinking resin.

The compound (A-1) used as a starting material in the production of the resin (A) is a compound having at least one hydroxyl group and at least one epoxy group in the same molecule and having a weight average molecular weight of 500 or more. , A copolymer obtained by using a hydroxyl group-containing polymerizable unsaturated monomer and an epoxy group-containing polymerizable unsaturated monomer as an essential component, and further copolymerizing with other polymerizable unsaturated monomer as necessary, Included.

The hydroxyl group-containing polymerizable unsaturated monomer used for preparing the compound (A-1) is a compound having one or more hydroxyl groups and one polymerizable unsaturated group in one molecule, and examples thereof include: 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 3
A hydroxyalkyl ester of acrylic acid or methacrylic acid having 2 to 8 carbon atoms such as hydroxypropyl (meth) acrylate or hydroxybutyl (meth) acrylate; a polyether polyol such as polyethylene glycol, polypropylene glycol or polybutylene glycol, and acrylic acid or Monoesters with unsaturated carboxylic acids such as methacrylic acid; and the like. These can be used alone or in combination of two or more.

The epoxy group-containing polymerizable unsaturated monomer used for preparing the compound (A-1) is 1 in 1 molecule.
A compound having one or more epoxy groups and one polymerizable unsaturated group, for example, glycidyl acrylate,
Examples thereof include glycidyl methacrylate, allyl glycidyl ether, 3,4-epoxycyclohexylmethyl acrylate, 3,4-epoxycyclohexylmethyl methacrylate, methyl-glycidyl acrylate, and methyl-glycidyl methacrylate. These can be used alone or in combination of two or more.

The compound (A-1) can be obtained by copolymerizing the above-mentioned hydroxyl group-containing polymerizable unsaturated monomer and epoxy group-containing polymerizable unsaturated monomer. The polymerizable unsaturated monomer may be used in combination for copolymerization.

The other polymerizable unsaturated monomer has a polymerizable unsaturated group in one molecule and does not contain a carboxyl group in principle, and specifically, for example, methyl (meth) acrylate. (Meth) acrylic acid such as ethyl, (meth) acrylate, butyl (meth) acrylate, hexyl (meth) acrylate, octyl (meth) acrylate, lauryl (meth) acrylate, cyclohexyl (meth) acrylate and the like and having 1 to 24 carbon atoms. 1
Monoesters with hydric alcohols; (meth) methoxybutyl (meth) acrylate, methoxyethyl (meth) acrylate, ethoxyethyl (meth) acrylate, etc.
Alkoxyalkyl ester of acrylic acid having 2 to 18 carbon atoms; vinyl acetates such as vinyl acetate, vinyl propionate, vinyl lactate, Veova monomer (trade name of Ciel Chemical Co., Ltd.), vinyl caprate, etc .; styrene, methylstyrene, etc. Vinyl aromatic compounds; nitrogen-containing unsaturated monomers such as acrylonitrile, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, (meth) acrylamide, vinylpyridine and vinylpyrrolidone; ethyl vinyl ether, n-
Propyl vinyl ether, butyl vinyl ether, octyl vinyl ether, cyclopentyl vinyl ether,
Vinyl ethers such as phenyl vinyl ether and benzyl vinyl ether; perfluorobutylethyl (meth) acrylate, perfluorononylethyl (meth)
Fluorine-containing unsaturated monomers such as acrylate and perfluorooctylethyl (meth) acrylate; and the like. These may be used alone or in combination of two or more.

The compound (A-1) can be obtained by copolymerizing the above monomer by a method known per se. In that case, the composition ratio of the monomer is such that one molecule of the compound (A-1) has at least one hydroxyl group and at least one epoxy group in the same molecule, preferably within the range of 2 to 10. If there is no particular limitation,
Generally, based on the total weight of the hydroxyl group-containing polymerizable unsaturated monomer and the epoxy group-containing polymerizable unsaturated monomer,
The hydroxyl group-containing polymerizable unsaturated monomer is 10 to 90% by weight,
20 to 60% by weight; preferably, the epoxy group-containing polymerizable unsaturated monomer is in the range of 90 to 10% by weight, particularly 80 to 40% by weight. Further, the other polymerizable unsaturated monomer is suitably used in an amount of 800 parts by weight or less, particularly 50 to 200 parts by weight, based on 100 parts by weight of the total amount of the both polymerizable unsaturated monomers. Then, the compound (A-
The weight average molecular weight of 1) is 500 or more, particularly 1000 to
It is preferably in the range of 100,000.

The self-crosslinking resin (A) is the above compound (A
It is obtained by subjecting the hydroxyl group of -1) to a ring-opening half-esterification reaction of a cyclic acid anhydride (A-2). The cyclic acid anhydride (A-2) used at that time is a compound having one or more carboxylic acid cyclic anhydride groups in one molecule,
For example, phthalic anhydride, succinic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, tetrabromophthalic anhydride, tetrachlorophthalic anhydride, hettic anhydride, hymic acid anhydride, maleic anhydride, trimellitic acid anhydride, pyromellitic acid anhydride, etc. These may be used alone or in combination of two or more.

The model of the ring-opening half-esterification reaction between the hydroxyl group of compound (A-1) and cyclic acid anhydride (A-2) is, as a model, 1 mol of hydroxyl group of cyclic acid anhydride (A-2). This is a reaction in which moles react to open the cyclic acid anhydride group to generate 1 mole of a free carboxyl group. This ring-opening half-esterification reaction can be carried out by a method known per se,
For example, it can be performed in an organic solvent at a temperature of about 40 to about 100 ° C. At that time, in order to accelerate the reaction, a catalyst such as an organic tin compound, an organic titanium compound, an organic zirconium compound can be used.

The ratio of both components to be used in the ring-opening half-esterification reaction can be arbitrarily selected according to the purpose. Usually, the cyclic acid anhydride ( A-2) is 0.2 to 1 mol, especially 0.1.
It is suitable to use it within the range of 5 to 1 mol.

A self-crosslinking resin (A) is obtained by the above ring-opening half-esterification reaction, and in each molecule, 1 free carboxyl group based on the ring-opening of an epoxy group and a cyclic acid anhydride group is obtained. There are more than one, preferably from 2 to 10, but there is no problem even if more hydroxyl groups remain.

Self-crosslinking resin (B): having an epoxy group and a cyclic acid anhydride group in the same molecule and having a weight average molecular weight of 5
00 or more of the compound (B-1) which is obtained by subjecting the cyclic acid anhydride group to the ring-opening half-ester reaction of the alcohol component (B-2), and a carboxyl group by ring-opening of the cyclic acid anhydride group in the same molecule; It is a self-crosslinking resin having one or more epoxy groups each.

The compound (B-1) used for the production of the resin (B) has a weight average molecular weight of 500 having at least one epoxy group and at least one cyclic acid anhydride group in the same molecule.
In the compound which is the above, for example, an epoxy group-containing polymerizable unsaturated monomer and a cyclic acid anhydride group-containing polymerizable unsaturated monomer as an essential component, and further using other polymerizable unsaturated monomer as necessary Those obtained by polymerization are included.

The epoxy group-containing polymerizable unsaturated monomer used for preparing the compound (B-1) is a compound having one or more epoxy groups and one polymerizable unsaturated group in one molecule. Specific examples include those exemplified as the epoxy group-containing polymerizable unsaturated monomer used for the preparation of the compound (A-1).

The cyclic acid anhydride group-containing polymerizable unsaturated monomer used for the preparation of the compound (B-1) includes at least one cyclic acid anhydride group and one polymerizable unsaturated group in one molecule. Examples of the compound having: maleic anhydride, itaconic anhydride and the like.

The compound (B-1) is obtained by copolymerizing the above-mentioned epoxy group-containing polymerizable unsaturated monomer and cyclic acid anhydride group-containing polymerizable unsaturated monomer. Other polymerizable unsaturated monomers may also be used in combination for copolymerization.

The other polymerizable unsaturated monomer has a polymerizable unsaturated group in one molecule and, as a general rule, does not have a carboxyl group and / or a hydroxyl group. It can be selected from the other polymerizable unsaturated monomers exemplified in the preparation of the component (A-1).

The compound (B-1) can be obtained by polymerizing the above-mentioned monomer by a method known per se. In that case, the composition ratio of the monomer is such that one molecule of the compound (B-1) has one or more epoxy groups and one cyclic acid anhydride group in the same molecule, preferably 2 to 10 each.
It is not particularly limited as long as it has a number within the range of, but generally, based on the total weight of the epoxy group-containing polymerizable unsaturated monomer and the cyclic acid anhydride group-containing polymerizable unsaturated monomer, epoxy group-containing 1 polymerizable unsaturated monomer
0 to 90% by weight, in particular 20 to 60% by weight; cyclic acid anhydride group-containing polymerizable unsaturated monomer is 90 to 10% by weight, especially 8
It is preferably used within the range of 0 to 40% by weight. Also,
The other polymerizable unsaturated monomer is 800 parts by weight or less based on 100 parts by weight of the total amount of the both polymerizable unsaturated monomers,
It is particularly suitable to use within the range of 50 to 200 parts by weight. The weight average molecular weight of the compound (B-1) is
It is preferably 500 or more, and particularly preferably in the range of 1000 to 100000.

The self-crosslinking resin (B) is the above compound (B
It can be obtained by subjecting the cyclic acid anhydride group of -1) to the ring-opening half-esterification reaction of the alcohol component (B-2). The alcohol component (B-2) used at that time
Is a compound having one or more, preferably one hydroxyl group in one molecule, and may have an ether bond, an ester bond, a urethane bond or the like in addition to the hydroxyl group, and the molecular weight of the component is 1,000. The following is preferable.
Specific examples include aliphatic monoalcohols such as methanol, ethanol, propanol and butanol; ether bond-containing monoalcohols such as ethylene glycol monomethyl ether and diethylene glycol monobutyl ether; These can be used alone or in combination of two or more.

The ring-opening half-esterification reaction of the cyclic acid anhydride group of the compound (B-1) and the hydroxyl group of the alcohol component (B-2) is modeled as follows. -2) is a reaction in which 1 mol of a hydroxyl group reacts to open the cyclic acid anhydride group to generate 1 mol of a free carboxyl group. The ring-opening half-esterification reaction can be carried out by a method known per se, for example, in an organic solvent at a temperature of about 40 to about 100 ° C. At that time, a catalyst such as an organic tin compound, an organic titanium compound, or an organic zirconium compound can be used to accelerate the reaction.

The ratio of the two components used in the ring-opening half-esterification reaction can be arbitrarily selected according to the purpose. Usually, the alcohol component is used per 1 mol of the cyclic acid anhydride group of the compound (B-1). The hydroxyl group of (B-2) is 0.2
It is suitable to use in the range of ˜1 mol, especially 0.5 to 1 mol.

A self-crosslinking resin (B) is obtained by the above ring-opening half-esterification reaction, and in each molecule, 1 free carboxyl group based on the ring-opening of an epoxy group and a cyclic acid anhydride group is obtained. There are one or more, preferably from 2 to 10, but it does not matter if more cyclic acid anhydride groups remain.

[0030]

The self-crosslinking resins (A) and (B) of the present invention described above can exhibit the following effects.

(1) Since it is self-crosslinking, it is not necessary to further add a curing agent.

(2) Regarding the self-crosslinking resin (A), in the copolymerization reaction system of the hydroxyl group-containing polymerizable unsaturated monomer and the epoxy group-containing polymerizable unsaturated monomer for preparing the compound (A-1), Since the reaction between the hydroxyl group and the epoxy group hardly occurs, gelation and partial high molecular weight are eliminated.

(3) Regarding the self-crosslinking resin (B), a copolymerization reaction system of an epoxy group-containing polymerizable unsaturated monomer and an acid anhydride group-containing polymerizable unsaturated monomer for preparing the compound (B-1) In the above, since the reaction between the epoxy group and the acid anhydride group hardly occurs, gelation and partial high molecular weight are eliminated.

(4) A carboxyl group based on the ring-opening of an acid anhydride group is superior in cross-linking reactivity with an epoxy group as compared with a normal carboxyl group such as acrylic acid, and is stable in storage at a temperature below the cross-linking reaction temperature. It is also excellent in sex.

[0035]

EXAMPLES Next, examples of the present invention will be described. In addition, both parts and% are based on weight in principle.

Example 1 Glycidyl methacrylate 2 mol / kg, 2-hydroxyethyl methacrylate 2 mol / kg and the balance n-
Acrylic resin consisting of butyl methacrylate (weight average molecular weight by GPC is 40,000) xylol 50%
2,000 g of the solution was mixed with 296 g of phthalic anhydride and 0.5 g of butyltin laurate, and the ring-opening reaction of the acid anhydride group was carried out at 50 ° C. for 8 hours to obtain a self-crosslinking resin (A). The Gardner viscosity of the resin solution is Z-4.
(20 ° C.), the nonvolatile content was 56.4%, the acid value of the resin was 85, and the weight average molecular weight was 45,000.

Example 2 2000 g of a 50% toluene solution of an acrylic resin (weight average molecular weight by GPC of 15000) consisting of 1 mol / kg of glycidyl acrylate, 1 mol / kg of maleic anhydride and the balance styrene and n-butyl methacrylate.
Then, 148 g of n-butanol and 0.1 g of butyltinoxyacetate were blended, and the ring-opening reaction of the acid anhydride group was carried out at 50 ° C. for 5 hours to obtain a self-crosslinking resin (B). The Gardner viscosity of the resin solution is S (20
C.), the nonvolatile content was 49.7%, the acid value of the resin was 52, and the weight average molecular weight was 20,000.

Example 3 Epicoat # 1004 (trade name, manufactured by Shell Chemical Co., Ltd.) 150
The solution was dissolved in 0 g of butyl acetate (1600 g), then 100 g of itaconic anhydride was added, and the mixture was reacted at 70 ° C for 5 hours. The obtained resin solution had a Gardner viscosity of W (20 ° C.), a nonvolatile content of 50.2%, an acid value of 35, and a weight average molecular weight of 4,700.

Example 4 A self-crosslinking resin was obtained by reacting under the same conditions as in Example 1 except that the entire amount of glycidyl methacrylate in Example 1 was replaced with methylglycidyl methacrylate. The Gardner viscosity of the obtained resin is Z-3 (20
℃), the nonvolatile content is 57.0%, the resin acid value is 83,
The weight average molecular weight was 45,000.

Example 5 In Example 1, the total amount of glycidyl methacrylate was 3,
All were reacted under the same conditions as in Example 1 except that 4-epoxycyclohexylmethyl acrylate was replaced to obtain a self-crosslinked resin. The obtained resin had a Gardner viscosity of Z-6 (20 ° C.), a nonvolatile content of 57.1%, a resin acid value of 82, and a weight average molecular weight of 45,000.

Comparative Example 1 Acrylic resin organic solvent solution having a weight average molecular weight of 40,000 consisting of 2 mol / kg of glycidyl methacrylate, 2 mol / kg of methacrylic acid and the balance of n-butyl methacrylate. The Gardner viscosity of the resin solution is P (20
℃), the nonvolatile content is 50%, the acid value of the resin is 11
2, the weight average molecular weight was 43,000. The resin solutions obtained in the above-mentioned Examples and Comparative Examples were tested for appearance, acetone extracted content and xylol wipeability. The results are shown in Table 1 below.

[0042]

[Table 1]

[0043]

【Test method】

1) Resin solution: The transparent solution was visually evaluated.

2) Acetone extraction: A resin solution was coated on a glass plate so as to have a thickness of 50μ, and
The coating film baked at 140 ℃ for 30 minutes in acetone solvent 3
The residual coating film weight (%) after time extraction was examined.

3) Xylol wiping property: The above baked coating surface was strongly rubbed with gauze moistened with xylol for 10
The coated surface after reciprocating was visually judged.

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Claims (2)

(57) [Claims] 1. A same weight-average molecular weight having an epoxy group and a cyclic acid anhydride group in the same molecule is characterized by reacting the ring-opening half-esterification of the alcohol component in the cyclic acid anhydride group 500 or more compounds A method for producing a self-crosslinking resin having a carboxyl group and an epoxy group by opening a cyclic acid anhydride group in the molecule. 2. An epoxy group and a cyclic acid anhydride group are the same.
The compound contained in the child is an epoxy group-containing polymerizable unsaturated model.
Of a polymerizable unsaturated monomer containing a nomer and a cyclic acid anhydride group
As an essential ingredient, and if necessary, other polymerizable
Obtained by copolymerization with a
The method of claim 1, wherein the method is one.