JPS58219232A - Preparation of unsaturated polyester modified with epoxy resin - Google Patents

Abstract

PURPOSE:To obtain the titled polyester, having remarkably improved anticorrosion and hardness of coating films, and useful for coating furniture, etc., by linking epoxy groups in a bifunctional bisphenol A type epoxy resin to an unsaturated polyester having allyl ether and COOH groups. CONSTITUTION:An unsaturated polyester having allyl ether and COOH groups, e.g. a partial ester of an unsaturated polybasic acid or an anhydride thereof such as maleic anhydride, with a polyhydric alcohol allyl ether having one OH group, is linked to epoxy groups in a bifunctional bisphenol A type epoxy resin of the formula (n is 0-3) to give the aimed unsaturated polyester modified with the epoxy resin. Acrylic acid or methacrylic acid is reacted with the above- mentioned epoxy groups to make acryloxy or methacryloxy group present at the same time. Thus, the gelation rate (air drying property) of coating films is remarkably improved.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing unsaturated polyester that has various properties that are even better than those of the prior art.

Unsaturated polyester resins obtained by reacting polybasic acids, polyhydric alcohols, and polyhydric alcohol allyl ethers are widely used as air-drying paints for painting furniture, interior materials, household goods, and the like. The coating has a curing speed, drying speed,
It has excellent properties in terms of abrasiveness, coating hardness, water resistance, etc., and its demand is increasing as it is one of the most practical paints.

However, in recent years, as technological innovations and social demands have become more sophisticated, there has been a demand for paints that further improve the above-mentioned properties and that also provide anti-corrosion properties when used in busy, humid or wet areas. has been done.

However, in order to solve the above problems, the present inventors have conducted extensive research into air-drying paints. As a result, we obtained a modified epoxy resin in which an unsaturated polyester having an allyl ether group and a carboxyl group (hereinafter abbreviated as allyl ether group-containing polyester) was bonded to the epoxy group in a bifunctional bisphenol A type epoxy resin. Unsaturated polyester has better corrosion resistance than conventional products.
In addition, the epoxy group is reacted with acrylic acid or methacrylic acid (hereinafter abbreviated as (meth)acrylic acid) to form (meth) into the epoxy resin-modified unsaturated polyester. ) The present inventors have discovered that the presence of an acryloxy group at the same time not only improves the above-mentioned properties, but also significantly improves the gelation rate and air-drying properties of the coating film, leading to the completion of the present invention.

The bifunctional bisphenol A type epoxy resin (hereinafter simply referred to as epoxy resin) in the present invention is a compound having the following structural formula, where n is usually selected from the range of 0 to 5.

1 Also, the epoxy equivalent of the epoxy resin is 100~□
500, preferably in the range of 180 to 600, and 10
If it is less than 0, the glass transition temperature will be too low and the drying rate will tend to drop, and if it is more than 500, the functional group equivalents of allyl ether groups and (meth)acryloxy groups will be too low when producing the unsaturated polyester of the present invention, resulting in hardening. This is not desirable as it slows down the speed.

The allyl ether group-containing polyester used in the present invention must contain a free carboxyl group in its molecule, and the carboxyl group is reacted with the epoxy group in the epoxy resin. Such unsaturated polyesters can be produced by any method, but usually polybasic acids, polyhydric alcohols, and polyhydric alcohol allyl ethers f! :1N74 to prepare an allyl group-containing unsaturated polyester in which at least one free carboxyl group remains in the molecule. As the polybasic acid, unsaturated polybasic acids such as maleic acid, heptamalic acid, itaconic acid, distraconic acid, and anhydrides thereof are used,
Phthalic acid, isophthalic acid, terephthalic acid, as required.
Saturated polybasic acids such as het acid, acyhinic acid, sebacic acid, succinic acid, azelaic acid, and anhydrides thereof can also be used in combination. Polyhydric alcohols include ethylene glycol, propylene glycol, phthylene glycol,
Examples include diethylene glycol, trimethylene glycol, triethyleneglyfur, trinotyrolethane, trimethylolpropane, dihydroxypentadiene, pentaerythritol, diglycerin, ditrimethylolpropane, and the like. Examples of polyhydric alcohol allyl ethers include glycerin monoallyl ether, trimethylolpropane monoallyl ether, trimethylolpropane diallyl ether, trimethylolethane monoallyl ether, trimethylolethane diallyl ether, pentaerythritol monoallyl ether, pentaerythritol diallyl ether, and pentaerythritol diallyl ether. Examples include erythritol triallyl ether, 1,2,6-hexandriol monoallyl ether, 1,2,6-hexandriol diallyl ether, sorbitan monoallyl ether, sorbitan diallyl ether, etc. In the present invention, It is not limited to these compounds.

Furthermore, the composition of the allyl ether group-containing polyester is not necessarily limited to the above composition, but it is a polyester having a polybasic acid, preferably an unsaturated polycarboxylic acid such as maleic anhydride or fumaric acid, and at least one hydroxyl group in the molecule. It may be a low molecular weight compound such as a partially esterified product with polyhydric alcohol allyl ether.

The desired epoxy resin-modified polyester can be obtained by reacting the allyl ether group-containing polyester with an epoxy resin. Specifically, it is common to prepare an allyl group-containing unsaturated polyester in advance, mix it with an epoxy resin, and react it. During the reaction of allyl ether to produce an allyl ether group-containing polyester in the system, a method such as mixing an epoxy resin with the polyester and continuing the reaction may be taken as appropriate. During the reaction, small amounts of 2-hydroxyethyl p-toluidine, 2-methylimitasole, trimethylbennylammonium chloride, etc. are added as catalysts. The reaction temperature is 50
-90°C, preferably 60-70°C.

As described above, by reacting the allyl ether group-containing polyester with the epoxy resin, the unsaturated polyester of the present invention contains bisphenol bone cores, allyl ether groups, and unsaturated polybasic acids such as maleic anhydride. The presence of an acid double bond means K. Due to the presence of these five components, it is possible to obtain excellent performance such as significantly improved anti-corrosion properties and coating hardness, without reducing the various properties of conventional air-drying paints.

In the above-mentioned epoxy resin-modified unsaturated polyester, the purpose can be sufficiently achieved if the epoxy resin component is present in an amount of 20 to 80% by weight based on the total polymer, but it is more preferable that the amount of the epoxy resin component is in the range of 50 to 70% by weight, and the corrosion resistance is remarkable. It is demonstrated. In addition, the number of allyl ether groups is 5 to 2 per total polymer.
Selected from the range of 0 weight ants. Epoxy resin component is 20
If it is less than % by weight, there is a tendency for the coating film hardness to decrease,
If it is used in an amount exceeding 80% by weight, the viscosity will become too high and a practical problem will remain.

In addition to the allyl ether group-containing polyester,
When meth)acrylic acid is bonded to the epoxy group in the epoxy resin, the curing speed of the coating film is significantly improved compared to when the allyl ether group-containing polyester is used alone, that is, the epoxy resin-modified unsaturated polyester has excellent air drying properties. is obtained.

(Meth)acrylic acid also has a carboxyl group in its molecule,
It reacts and bonds with the epoxy groups in the epoxy resin.

K, which combines an allyl ether group-containing polyester and (meth)acrylic acid with an epoxy resin, is usually produced by manufacturing an allyl ether group-containing polyester using the method described above, and combining this with an epoxy resin and (meth)acrylic acid. A method of reacting at a temperature of 70 to 110°C is used,
Examples include a method of first reacting an epoxy resin with an allyl ether group-containing polyester, or a method of reacting an epoxy resin with (meth)acrylic acid, and then reacting the remaining component, but the present invention is not limited to these methods. It's not something you can do.

(Meth)acrylic acid is 5 to 0 to the total polymer. It is desirable that it is wheel weight %.

The molecular weight of the epoxy resin-modified unsaturated polyester of the present invention is 1000 to 5000, more preferably 1500 to 25
A range of 00 is preferred. If the molecular weight is less than 1000, the coating viscosity will be too low and the curing speed will decrease;
In the above cases, the viscosity is too high, and unless a large amount of styrene or the like is used, the coating viscosity cannot be achieved, resulting in a decrease in the curing speed, and should be avoided.

Furthermore, when the unsaturated polyester is used for coatings, it is generally mixed with a polymerizable monomer. As a polymerizable monomer, styrene, vinyltoluene, chlorostyrene, α-methylstyrene, divinylbenzene, (meth)acrylic acid ester, glycidyl methacrylate, vinyl acetate, diallylphthalate, triallyl cyanurate, trimethylolpropane triacrylate , trimethylolpropane trimethacrylate, tung oil, linseed oil, soybean oil, cottonseed oil, safflower oil, coconut oil, and the like.

When used as a paint, it is necessary to further add pigments, fillers, curing agents, curing accelerators, diluents, thermoplastic resins, etc. as additives.

Examples of pigments include titanium white, cyanine blue, cream yellow, watching red, red iron, carbon black, and aniline black.

Examples of the curing agent include methyl ethyl ketone peroxide, cyclohexanone peroxide, benzoyl peroxide, dicumyl peroxide, and tert-butyl perbenzoate.

Examples of the curing accelerator include cobalt octylate, cobalt naphthenate, and manganese naphthenate.

Examples of the diluent include ethyl acetate, toluene, xylene, methanol, ethanol, butanol, acetone, methyl ethyl ketone, methyl isobutyl ketone, Cellosol, and cyacetone alcohol.

Examples of the thermoplastic resin include cellulose acetate ghylate, nitrocellulose, vinyl acetate chloride resin, vinyl acetate resin, acrylic resin, copolymers thereof, butylated melamine, butylated urea, and the like.

Other additives include phosphoric acid, tartaric acid, phosphorous acid, oils and fats, silicone oil, surfactants, paraffin wax, and the like.

The resin composition of the present invention can be used anywhere as a paint. Examples of target objects include wood paint (furniture, musical instruments, etc.), automobile repair putty, FRP molding, and cast molding.

In particular, the excellent feature of the present invention is that it has very good anti-corrosion properties, making it ideal for heavy-duty anti-corrosion flake coating paints and gel coat coatings for FRP moldings.

The present invention will be specifically described below with reference to Examples.
・In addition, "1%" in the example is based on weight.

Example 1 0.45 mole of glycerin monoallyl ether, 1.0 mole of maleic anhydride, and 0.5 mole of ethylene glycol were reacted at a temperature of 180"C for 6 hours to obtain an allyl ether group-containing polyester. m As a new ingredient, bisphenol A diglycidyl ether 0.5
2-hydroxy para-toluidine was added in an amount of 0.5% based on the total system and reacted at 90°C for 1 hour, and methanol was added at 2.5% based on the total system and reacted for another 1 hour. After that, a vacuum treatment was carried out at 10 +a+)iy for 50 minutes to obtain a resin content of 60%, an acid value of 18''9KOH/p, and a viscosity of 3.
An epoxy resin-modified unsaturated polyester was obtained in which the content of DOOcps and z poxy resin components was 6o96 based on the total polymer. Styrene as a polymerizable monomer and hydroquinone as a polymerization inhibitor were added to this in an amount of 5% and 5%, respectively, and the performance when used as a paint was evaluated by the method described below.

Example 2 Raw materials for polyester containing allyl ether group: 0.25 mol of trimethylolpropane diallyl ether, 4200.7 mol of male anhydride, 0.5 mol of isophthalic acid, 0.5 mol of furopylene gelicol, and [zyK xy resin] Using 0.5 mol of bisphenol A diglycidyl ether as a component, K was prepared in the same manner as in Example 1 to obtain a resin content of 60% and an acid value of 1.
5 wqKOf(/f, viscosity 2500 cps,
Content of epoxy resin component in total polymer: 155%
Epoxy resin-modified unsaturated polyester 1 Instead of the epoxy resin-modified unsaturated polyester used in Example 1, 1.0 mol of maleic anhydride, 5 mol of hydrogenated bisphenol A, 0.5 mol of propylene glycol, and ethylene glycol were added. Using 1.5 mole of recall as raw material, resin content is 6096, acid value is 22WIyKOH/y, viscosity is 5000
CPS common unsaturated polyester was obtained and used as a paint in the same manner as the spinning process.

Comparative Example 2 Instead of the epoxy resin-modified unsaturated polyester used in Example 1, 0.25 mol of trimethylolpropane diallyl ether, 1.0 mol of maleic anhydride, 0.5 mol of fluoropylene gellicol, and 0.5 mol of ethylene glycol were used. Using 5 moles as raw material, resin content is 60% and acid value is 20"P KOR.
/! An allyl ether group-containing unsaturated polyester having a viscosity of 2100 cps was obtained and used as a paint in the same manner as in Example 1.

The results of Examples 1 and 2 and Comparative Examples 1 and 2 are summarized in Table 1.

Performance evaluation was performed using the following method.

1) Surface drying property The obtained paint with a resin content of 60% is further dried with a styrene solution for an additional 50%
%, then 0.5% of cobalt octenoate (cobalt content 896) and 1% of Vermec N (methyl ethyl keto % solution manufactured by NOF Corporation) were added. Apply this 0.5 glue on a glass plate with an applicator, check that it is dry to the touch, then place carbon paper on the coated surface and apply 5 glue to it.
A load of 5 Kf was applied to c+++X5cm, and the presence or absence of tack was determined based on the degree of carbon remaining. In a completely tack-free state, no carbon transfer is observed.

2) Pencil hardness Based on JIS K5401 K, marks made by a pencil φ were erased with an eraser, and the hardness value is shown as the value when there are no scratches.

5) Corrosion resistance Changes in the painted surface were examined under the conditions described below.

Pure water resistance = 72 hour immersion in pure water at 90°C Acid resistance: 0%
6 months in hydrochloric acid (at room temperature) Alkali resistance: 6 months in 5096 sodium hydroxide aqueous solution (at room temperature) Table 1 Example 5 0.45 mole of diallylpentaerythritol and 1.0 mole of maleic anhydride were mixed at a temperature of 60°C for 2 hours. To the allyl ether group-containing polyester obtained by the reaction, 0.5 mol of acrylic acid, 0.5 mol of bisphenol A diglycidyl ether, and! [.

For the skin, 596 amounts of 2-hydroxyethyl para-toluidine were charged in bulk and reacted at 90°C for 10 hours.
Cool to 0°C, add 2% methanol to the total system, react for another 1 hour, and perform a vacuum treatment at IOmHg for 50 minutes to obtain a resin content of 60% and an acid value of 1 KOH/f.

Viscosity: 2500 cps, content of epoxy resin component and acrylic component relative to total polymer: 50% each, 15%
% of epoxy resin modified unsaturated polyester was obtained. To this, 0.00% each of styrene and hydroquinone were added to the entire system.
0596 was added to the paint, and the performance was evaluated in the same manner as in Example 1.

Examples 4 to 6 Paints were obtained in the same manner as in Example 5, except that the composition other than diallylpentaerythritol was changed as shown in Table 2, and performance evaluation was performed.

The content of epoxy resin component and acrylic acid on each side was 45% and 15% for example 4, 10% and 5096 for example 5, and 1096.50% for example 6, based on the total polymer.

Table 2 Example B8 Paints with a resin content of 6096 were obtained in the same manner as in Example 3.4 except that methacrylic acid was used instead of acrylic acid, and their performance was evaluated. In addition, each acid value viscosity and the content of epoxy resin component and methacrylic acid in the total polymer were 15K (I(/fS5000 cps) in Example 7.
, 50%, Example 8 at 20%, 17qKOH/f,
It was 5500 cps, 4'5%, 17%.

Example? In Example 3, resin content 65%, acid value 5,0+, '9KOH/p, '9KOH/p, An epoxy resin-modified unsaturated polyester having a viscosity of 5,700 cps and an epoxy resin component and an acrylic acid content of 54% and 15%, respectively, based on the total polymer was obtained and used as a paint to evaluate its performance.

The results of the performance evaluation of Examples 5 to 9 are summarized in Table 5.

Table 5

Claims (1)

[Claims] 1. A method for producing an epoxy resin-modified unsaturated polyester, which comprises bonding an unsaturated polyester having an allyl ether group and a carboxyl group to an epoxy group in a difunctional bisphenol A-type epoxy resin. 2. An unsaturated polyester having an allyl ether group and a carboxyl group is mixed with an unsaturated polybasic acid or its anhydride.
2. The method for producing an unsaturated polyester according to item 1, which is a partial ester/L-compound with a polyhydric alcohol allyl ether having hydroxyl groups. 6. The method for producing an unsaturated polyester according to item 2, wherein the unsaturated polybasic acid or its anhydride is maleic anhydride. 4. An unmodified epoxy resin characterized in that (a) an unsaturated polyester having an allyl ether group and a carboxyl group and (b) acrylic acid or methacrylic acid are bonded to the epoxy group in the bifunctional bisphenol A type epoxy resin. Manufacturing method of saturated polyester. 5. The unsaturated polyester having an allyl ether group and a carboxyl group is an unsaturated polybasic acid or its anhydride (!
- The method for producing an unsaturated polyester according to item 4, which is a partially esterified product with a polyhydric alcohol allyl ether having one hydroxyl group. 6. Production of an unsaturated polyester according to item 5, wherein the unsaturated polybasic acid or its anhydride is maleic anhydride.