JPS6354006B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an unsaturated polyester resin composition that is not inhibited from curing in an air environment, and is particularly characterized by excellent storage stability. As used herein, "air curing type" means "a type in which curing is not inhibited in an air environment." Unsaturated polyester resins made by mixing unsaturated polyesters with polymerizable monomers are often cured in air. In that case, on the surface that comes into contact with the air, curing is inhibited due to the inhibiting effect of oxygen in the air on the polymerization reaction, leaving stickiness on the surface of the cured product, or elution occurs when it comes into contact with organic solvents. . Conventionally, in order to prevent such curing inhibition caused by air, it was necessary to prevent the surface of the cured product from coming into contact with air during curing, or to convert unsaturated polyester resin into air-curable unsaturated polyester resin whose curing is not inhibited by air. A method of using resin has been adopted. The former method involves dissolving wax in an unsaturated polyester resin and forming a precipitated wax film on the surface of the cured product, but the presence of wax causes poor adhesion or poor wetting. If this is not desired, the latter air-curable unsaturated polyester resin is used. This resin is a resin that uses a component that easily reacts with oxygen as a part of the resin component, and hardens as a result of the decomposition of a complex formed by absorbing and dissolving oxygen in the air. It is a saturated polyester resin. The presence of oxygen promotes curing of this resin. Therefore, air-curable unsaturated polyester resins are unstable when stored in air;
In particular, when a curing accelerator such as cobalt naphthenate or manganese naphthenate is present, the resin is extremely unstable, and curing proceeds from the surface of the resin, forming a film on the surface. This phenomenon is called the skinning phenomenon. In order to avoid the skinning phenomenon, it is widely practiced to add antioxidants such as phenol derivatives, but this significantly delays the gelation time of the resin and significantly impedes the original purpose of air curing. inhibited. In addition, wrinkles are likely to occur in the cured film of air-curable unsaturated polyester resin. The present invention was achieved as a result of studies aimed at improving the prevention of skinning phenomenon, storage stability, and wrinkle prevention of cured films without impairing the air curability, which is the original purpose of air-curing unsaturated polyester resins. It is something. That is, the present invention provides an unsaturated polyester resin whose curing is not inhibited in an air environment, and 0.01 to 0.5 parts by weight of benzyldimethylamine, tris(dimethylamino)mesitylene, bis(dimethylamino) based on 100 parts by weight of the resin. An unsaturated polyester resin composition that does not inhibit curing in an air environment, characterized by containing one or more compounds selected from the group of xylene and N, N, N', N'-tetramethylethylenediamine. . A general unsaturated polyester resin is a resin made by mixing a polymerizable monomer with an unsaturated carboxylic acid as an acid component, a saturated carboxylic acid if necessary, and an unsaturated polyester reacted with a polyol as an alcohol component. The unsaturated carboxylic acids mainly used are unsaturated dicarboxylic acids such as fumaric acid, maleic acid, and itaconic acid, and the saturated carboxylic acids mainly used are saturated dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, adipic acid, and sebacic acid. Acid is used. As a polyol,
Mainly ethylene glycol, propylene glycol, butanediol, diethylene glycol,
Glycols such as dipropylene glycol, neopentyl glycol, bisphenol A, hydrogenated bisphenol A, and alkylene oxide adducts of bisphenol A, and polyols such as glycerin and pentaerythritol are used. Examples of polymerizable monomers include vinyl monomers such as styrene, α-methylstyrene, vinyltoluene, tert-butylethylene, chlorostyrene, divinylbenzene, acrylic acid or its esters, methacrylic acid or its esters, or diallyl. One type or a mixture of two or more types of allylic monomers such as phthalate can be used. The air-curable unsaturated polyester resin in the present invention is a resin that uses a component that easily reacts with oxygen as a part of the components of the above-mentioned general unsaturated polyester resin, that is, a resin that uses the components that easily react with oxygen, that is, the unsaturated polyester resin listed in (1) to (5) below. One or more resins selected from the group of saturated polyester resins. (1) The acid component of the unsaturated polyester is tetrahydrophthalic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, α-terpinene-maleic anhydride adduct, rosin, ester gum, drying oil fatty acid, semi-drying oil fatty acid. An unsaturated polyester resin modified with one or more compounds selected from the group consisting of: (2) The alcohol component of the unsaturated polyester is one or more selected from the group consisting of β, γ-alkenyl ethers or benzyl ethers of polyhydric alcohols such as glycerin monoallyl ether and pentaerythritol diallyl ether. An unsaturated polyester resin modified with a compound of (3) An unsaturated polyester selected from the group consisting of isocyanate compounds and epoxy compounds.
Unsaturated polyester resin modified with a species or two or more compounds. (4) As a polymerizable monomer, one or more compounds selected from allyl ethers such as allyl ether of methylolmelamine, adipic acid ester of glycerin diallyl ether, allyl acetal, and allyl ether of methylolglyoxal urein. unsaturated polyester resin using. (5) Unsaturated polyester resins to which drying oils are added, such as cyclopentadienated oils made by reacting cyclopentadiene and oil, and epoxidized oils made by epoxidizing drying oils. In the composition of the present invention, benzyldimethylamine, tris(dimethylamino)mesitylene, bis(dimethylamino)xylene and N,N,N',
One or more compounds selected from the group of N'-tetramethylethylenediamine (hereinafter referred to as a compound represented by benzyldimethylamine) are contained. The blending amount thereof is 0.01 to 0.5 parts by weight per 100 parts by weight of the above-mentioned air-curing unsaturated polyester resin, and a conventional method can be used for blending. If the amount is less than 0.01 part by weight, no skinning prevention effect can be expected, and if it exceeds 0.5 part by weight, curing will be insufficient and surface drying properties will be particularly poor. The air-curable unsaturated polyester resin composition of the present invention may contain a curing agent (catalyst), a curing accelerator, a polymerization inhibitor, etc. in addition to a compound typified by benzyldimethylamine. By containing a compound represented by benzyldimethylamine, the air-curing unsaturated polyester resin composition of the present invention has the effect of preventing skinning phenomenon and storage stability at the same time without impairing air-curing properties. Furthermore, it is possible to prevent the occurrence of wrinkles after the film is cured. A compound represented by benzyldimethylamine imparts the above-mentioned properties only to an air-curable unsaturated polyester resin, and when added to a non-air-curable unsaturated polyester resin, it extremely deteriorates surface curability. The air-curable unsaturated polyester resin composition of the present invention can be used in solvent-free electrical insulation varnishes, adhesives, general paints, and the like. The present invention will be specifically explained below using examples.
In the examples, simply % means % by weight, and parts means parts by weight. In addition, the test method for the gel formation time that indicates skin stability in the examples is to add a curing accelerator to an air-curable unsaturated polyester resin composition, take 20g of this into a test tube, and seal it with a rubber stopper. The samples were left in a constant temperature room at 60°C, and the results were expressed as the time it took for a gel-like substance to form at the interface between the resin liquid and air. Next, the wrinkle generation test was performed by pouring an air-curing unsaturated polyester resin composition containing a curing agent onto a 1 mm thick tin plate, and heating and curing it at 120°C for 30 minutes. Visually observe. Furthermore, the storage stability test method is to take 20g of the above resin solution containing the curing agent into a test tube, place it in a constant temperature room at 25℃, and measure the number of days or hours until the lower part of the resin solution becomes gel-like. displayed. The curing agent is 1.0 phr of perhexachloride for unsaturated polyester resin compositions.
3M (organic peroxide manufactured by NOF Corporation) was added. Example 1 8.4 parts of glycerin monoglyceride in linseed oil,
An unsaturated polyester derived from 6.2 parts of cyclopentadiene dimer, 13.1 parts of ethylene glycol, 11.6 parts of maleic anhydride, and 11.7 parts of phthalic anhydride was dissolved in 48 parts of styrene to produce an air-curable unsaturated polyester resin. The viscosity of this resin is 0.5
It was poise (25℃). To this resin were added 0.03 part of hydroquinone as a polymerization inhibitor to prevent gelation, and 0.03 part of cobalt naphthenate (6% xylene solution) as a curing accelerator. Then, benzyldimethylamine was added to the air-curable unsaturated polyester resin in the amount shown in Table 1. The gel generation time, wrinkle generation test, and storage stability results of each unsaturated polyester resin composition to which benzyldimethylamine was added,
Table 1 shows a comparison with one without the addition of benzyldimethylamine.

[Table] Example 2 Soybean fatty acid 32.28 parts, phthalic anhydride 4.26 parts, maleic anhydride 8.48 parts, pentaerythritol 8.18 parts
An air-curable unsaturated polyester resin was prepared by dissolving an unsaturated polyester derived from 6.64 parts of propylene glycol into 37 parts of 2-hydroxyethyl methacrylate. The viscosity of this resin is 5.0
It was poise (25℃). To this resin, 0.03 part of hydroquinone as a polymerization inhibitor and 0.2 part of cobalt naphthenate (6% xylene solution) as a curing accelerator were added to prevent gelation. Next, when 0.1 part of benzyldimethylamine was added to 100 parts of the air-curable unsaturated polyester resin, the gel formation time was 4 days, no wrinkles were formed, and the storage stability was 13 days. Note that if benzyldimethylamine is not added, the gel formation time will be
Wrinkles appeared after 0.5 days, and storage stability was 13 days.

Claims (1)

[Scope of Claims] 1. One or more unsaturated polyester resins selected from the group listed below (1) to (5) whose curing is not inhibited in an air environment, (1) unsaturated polyester The acid component of is selected from the group consisting of tetrahydrophthalic anhydride, 3,6-endomethylenetetrahydrophthalic anhydride, α-terpinene-maleic anhydride adduct, rosin, ester gum, drying oil fatty acid, semi-drying oil fatty acid. (2) Unsaturated polyester resin modified with one or more compounds (2) The alcohol component of unsaturated polyester is converted into β, γ-alkenyl ether or benzyl ether of a polyhydric alcohol such as glycerin monoallyl ether or pentaerythritol diallyl ether. Unsaturated polyester resin modified with one or more compounds selected from the group consisting of (3) Unsaturated polyester modified with one or more compounds selected from the group consisting of isocyanate compounds and epoxy compounds 1
Unsaturated polyester resin modified with a species or two or more compounds (4) Allyl ether of methylolmelamine, adipic acid ester of glycerin diallyl ether, allyl acetal, allyl ether of methylolglyoxal urein as a polymerizable monomer Unsaturated polyester resin using one or more compounds selected from (5) Cyclopentadienated oil obtained by reacting cyclopentadiene and oil, and epoxidized drying oil obtained by epoxidizing drying oil. 0.01 to 0.5 parts by weight of benzyldimethylamine, tris(dimethylamino)mesitylene, bis(dimethylamino)xylene and N,N,N',N'-tetramethylethylenediamine per 100 parts by weight of the resin. 1. An unsaturated polyester resin composition which is not inhibited from curing in an air environment, and is characterized by containing one or more compounds selected from the group consisting of: