JPS5821648B2 - Fuhouwa Polyester Keiji Yushino Seizouhouhou - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing a novel unsaturated polyester resin having excellent thermal stability.

Conventionally, unsaturated polyester resins are produced by mixing an unsaturated dibasic acid and a polyhydric alcohol, gradually heating the mixture to a desired temperature, performing five reactions, and then lowering the temperature and removing excess polyhydric alcohol under reduced pressure. That's what you're getting.

However, in this case, since aliphatic polycarboxylic acids such as maleic anhydride, fumaric acid, itaconic acid, etc. are generally used as the unsaturated dibasic acid, the resulting resin has insufficient heat resistance and is classified as A type. It was of a certain extent.

The inventors of the present invention conducted extensive research in an effort to develop an unsaturated polyester resin with further excellent heat resistance characteristics, and as a result, they discovered that an unsaturated polyester resin with excellent properties could be obtained.

That is, the method of the present invention is a carbon-carbon double bond consisting of the general formula [where A is an aliphatic hydrocarbon group having 2 to 5 carbon atoms, and B is -CH-CH-2 (however, R is an alkyl group]. A dicarboxylic acid represented by [containing 2WJ group] alone or a mixture in which a part of the dicarboxylic acid is replaced with another polyhydric carboxylic acid or a functional derivative thereof, and a polyhydric alcohol are produced by heating reaction. It is.

The production method of the present invention uses an imide group-containing unsaturated dicarboxylic acid represented by the above formula (1) alone, or an acid component in which a part of the dicarboxylic acid is replaced with another polyhydric carboxylic acid or a functional derivative thereof. The mixture may be mixed with a polyhydric alcohol and subjected to a heating reaction in the presence of a catalyst such as tin oxalate in a process similar to the conventional method for producing polyester resin using an aromatic dicarboxylic acid.

However, the reaction ratio between these acid components and polyhydric alcohol is different from that in the production of conventional saturated polyester resins.

That is, conventional polyester resins do not have high molecular weight unless equivalent amounts of dicarboxylic acid and polyhydric alcohol are used.
Although it is not possible to obtain a product with excellent heat softening resistance or chemical resistance, in the present invention, the acid component contains a double bond as shown in the formula (1) above, and is self-curing by heating or a catalyst. Because we use a special acid that does this, even if the acid or polyhydric alcohol has an excess of up to 1.4 times the amount of the acid or polyhydric alcohol, products with excellent heat resistance, chemical resistance, and other properties can be obtained. It is something.

Therefore, the unsaturated polyester resin obtained according to the present invention can be produced with a low molecular weight and cured by direct molding and heating, or by dissolving it in a solvent and applying it to a conductor as a paint and baking it with equal diameter heating. At the same time, the resin can be made to have a high molecular weight, so handling of the resin is extremely easy.

The imide group-containing unsaturated dicarboxylic acid represented by the above formula (1) can be obtained as follows.

That is, vinyl-type or A dicarboxylic acid anhydride containing a vinylene-type unsaturated bond is heated and reacted with an aliphatic amino alcohol such as monoethanolamine or impropatulamine to form a monoalcohol containing an imide group, which is then converted into trimellitic acid anhydride. It is obtained by reacting with

This imide group-containing unsaturated dicarboxylic acid is usually synthesized in advance, then separated and purified before use.
You can also use

Further, in the present invention, other polyhydric carboxylic acids or functional derivatives thereof which can be used as a part of the imide group-containing unsaturated dicarboxylic acid shown in formula (1) above include, for example, dimethyl Terephthalic acid, dimethyl isophthalic acid, succinic acid, maleic acid, benzophenone dicarboxylic acid, 2.6 naphthalene dicarboxylic acid, N, N'(4
-carboxyphenyl)pyromellitimide, benzophenonetetracarboxylic anhydride, 4,4' diphenylmecune-bisutrimellitimide, etc., and these can be used alone or in combination of two or more.

The mixing ratio of the dicarboxylic acid represented by the formula (1) and the polyhydric carboxylic acid described above is not particularly limited, but is preferably within a range of less than 50 molar ratio in view of the physical properties of the resulting resin.

Further, the polyhydric alcohols used in the present invention include ethylene glycol, glycerin, trimethylolpropane, 1,4 bucundiol, tris(2-hydroethyl)in cyanurate, tris(2-hydroxyisopropyl)isocyanurate, furopylene gellicol, N,
N', (hydroxyethyl)pyromellitimide, etc., and these can be used alone or in combination of two or more.

Furthermore, in order to further improve the properties of the resin obtained in the present invention, it is effective to use lauryl, mercaptan, cobalt naphthinate, dimethylaniline, etc. as a polymerization catalyst such as an organic peroxide as well as a reaction promoter. be.

Further, organic compounds such as tetrabutyl titanate and tetraisopropyl titanate, stabilized polyisocyanates, phenol resins, melamine resins, epoxy resins, etc. can be added for modification.

Further, unsaturated compounds such as styrene and diallylphthalate, unsaturated oils, natural resins, etc. may be added.

Next, examples of the present invention will be described.

Example I 66 g of trimellitic acid monomaleic acid imide ethyl ester obtained by reacting equimolar amounts of N-hydroxyethylmaleimide and trimellitic anhydride and 13 g of ethylene glycol were mixed with 0.1 g of tin oxalate in 50 g of Fresol.
At the same time, the reaction temperature was gradually raised to 180°C, and the reaction was heated for 5 times to obtain a viscous solution of about 5000 CP at 30°C.

After applying this solution once to a copper wire of 1.0 imψ,
Baking was performed at ℃ to obtain an insulated wire with a coating thickness of 40μ.

The dielectric breakdown voltage of the insulated wire thus obtained was measured.1
The thermosetting temperature of the film was 310° C. under a load of 1 kg and a voltage of 3 kV.

For comparison, an insulated wire manufactured in the same manner using polyester obtained by reacting terephthalic acid and ethylene glycol and varnish using polyester obtained by reacting with ethylene glycol using maleic acid as the unsaturated dicarboxylic acid. The softening temperature was measured by the same method as above and was 250° C. or lower in all cases.

Example 2 66 g of trimellitic acid monomaleic acid imidoethyl ester and 60 g of bishydroxyethyl terephthalate as in Example 1 were mixed with 0.1 g of antimony trioxide and 0.1 g of tin oxalate.
The reaction temperature was gradually raised to 180°C with 1.9, and a viscous solution of 1200 CP was obtained at 80°C. To this solution, 1 g of dicumyl peroxide was added.
was added, heated at 80°C, and applied once to a copper wire of 1.0 μm, followed by baking at 480°C to obtain an insulated wire with a coating thickness of 35 μm.

When the dielectric strength voltage of the electric wire was measured, it was 8 kV and 2
Even after heat treatment at 30°C for one week, the film showed 6 kV, and even when wound around its own diameter, the film showed good properties without cracking.

Example 3 In cresol 509, 33 g of trimellitic acid monomaleic acid imidoethyl ester similar to Example 1 and 26 g of tris(2-hydroxyethyl) incyanurate were added with antimony trioxide o and ig silver oxalate 0.1 g, respectively. The reaction temperature was gradually increased to 200°C, and a viscous solution of 1500 CP was obtained at 30°C. After coating this solution twice on an aluminum wire of LOmwψ, the reaction temperature was heated at 450°C. Baking was performed to obtain an insulated wire with a coating thickness of 45 μm.

When the dielectric breakdown voltage of the electric wire was measured, it was found to be 13 kV, and when the thermal softening temperature was measured under a load of 1 kg, no softening occurred even at 400°C.

Example 4 Monoethanolamine and 3.6 endomethylene 1.2,
Trimellitic acid mono-3,6 endomethylene 1,2,3 obtained by reacting using equimolar amount of 3,6 tetrabidolphthalic anhydride and then adding equimolar amount of trimellitic acid thereto. .6 40 g of tetrabidolphthalic acid imido-engineered methyl ester, 11 maleic acid and 15 g of ethylene glycol were combined with 0.05 g of antimony trioxide and 0 tin oxalate.
．． A resin having a melting point of 80° C. was obtained by heating and reacting with 05 and 05 and 9.

This resin was heated to 90°C, applied to a 0.2 mm thick copper plate, and heated and cured in a 400°C furnace to achieve a film thickness of 3.
A 0μ insulating copper plate was obtained.

When the copper plate was wound around a 2 mm ψ rod, no cracks were formed in the film formed, and the dielectric strength of the film was 3.5.
It was kV.

As detailed above, according to the present invention, it is possible to obtain an unsaturated polyester resin which has much better heat resistance than conventional unsaturated polyester resins, and its industrial value is extremely great.

Claims (1)

[Claims] 1 General formula [wherein A is an aliphatic hydrocarbon group having 2 to 5 carbon atoms, and B is a carbon-carbon double compound consisting of -CH-CH-2 (wherein R is an alkyl group)] A group of 21i111i that overlaps bonds] A dicarboxylic acid alone or one of dicarboxylic acids represented by
1. A method for producing an unsaturated polyester resin, which comprises heating and reacting a mixture in which part of the polyhydric carboxylic acid or its functional derivative is substituted with a polyhydric alcohol.