JPS61101513A - Curing of unsaturated polyester - Google Patents

Abstract

PURPOSE:To ensure a necessary pot life and enhance the rate of internal curing and the rate of surface curing, by curing an unsaturated polyester in the presence of a curing catalyst in combination with a sulfinate. CONSTITUTION:In curing an unsaturated polyester, a sulfinate is used in combination with a curing agent. An unsaturated polyester can be obtained by condensing a polyhydric alcohol with an unsaturated polybasic acid and, at this time, it is preferable to impart air dryability to the polyester by using a polyalcohol allyl ether together with the above components. It is preferable that this polyalcohol allyl ether is used in an amount of, usually, at least 0.3mol per mol of the polybasic acid. The sulfinate include sodium salts and ammonium salts of benzenefulfinic acid and styrenesulfinic acid and are used in an amount of about 0.05-2wt% based on the total.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for curing unsaturated polyesters, particularly air-drying unsaturated polyesters containing allyl groups.

Conventional technology Unsaturated polyesters or modified products thereof obtained by reacting polyhydric alcohols, polybasic acids, and polyhydric alcohol allyl ethers are air-drying, have a desirable luster and texture, and have a beautiful finish. It is useful as a raw material resin for general wood coatings, including furniture and interior materials.

The curing of this allyl group-containing air-drying unsaturated polyester is
Combinations of radical polymerization initiators and metal soaps in the presence of crosslinking agents such as styrene monomers, such as methyl ethyl ketone peroxide and cobalt octenoate, methyl ethyl ketone peroxide and cobalt naphthenate, cumene hydroperoxide and naphthenic acid. This was done using cobalt, etc.

In addition, unsaturated polyesters obtained by reacting polyhydric alcohols and polybasic acids are also useful as resins for paints, but the curing of this resin is carried out in the presence of crosslinking monomers such as styrene monomers. Combinations of radical polymerization initiators and amines or amine salts, such as benzoyl peroxide and dimethyl p-toluidine, penzoyl peroxide and p-methylaniline, etc. have been used.

Problems to be Solved by the Invention However, depending on these curing catalysts, in order to secure the required pot life, the amount of curing catalyst used must be reduced, which slows down the curing speed and reduces productivity. On the other hand, if you try to increase the curing speed,
Since a large amount of curing catalyst must be used, there is a problem in that the pot life is shortened and workability is hindered.

The present invention aims to solve these problems by coexisting a specific compound in the system.

Means for Solving the Problems The present invention provides the following features: ``When curing unsaturated polyester by a conventional method,
A method for curing unsaturated polyester characterized by the coexistence of a sulfinate. '', and as a result, we succeeded in increasing the internal curing speed and surface curing speed while securing the necessary pot life.

The present invention will be explained in detail below.

The unsaturated polyester in the present invention is obtained by condensation reaction of a polyhydric alcohol and an unsaturated polybasic acid according to a conventional method. At this time, polyhydric alcohol allyl ether is used together with these components, It is desirable to give

Examples of polyhydric alcohols include ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, dipropylene glycol, bisphenol dioxypropyl ether, 1,3-butylene glycol, , 3-butylene gellicol, ■, 6-hexanediol, 2-ethyl-1,3-hexanediol, 2,
2.4-trime f roux 1. , 3-bentanediol, neopentyl glycol, trimethylolethane, trimethylolpropane, glycerin, pentaerythritol, and the like.

As the unsaturated polybasic acid, maleic anhydride, maleic acid, itaconic anhydride, itaconic acid, fumaric acid, etc. are used. Along with these unsaturated polybasic acids, phthalic anhydride, phthalic acid, terephthalic anhydride, isophthalic acid, and tetrahydrophthalic anhydride.

endomethylenetetrahydrophthalic anhydride, het-e,
Saturated polybasic acids such as citracone, adipic acid, and heptad/hesic acid can also be used in combination.

Examples of polyhydric alcohol allyl ethers include pentaerythritol triallyl ether, pentaerythritol diallyl ether, trimethylolpropane diallyl ether, trimethylolpropane monoallyl ether, trimethylolethane diallyl ether, trimethylolethane monoallyl ether, glycerin diallyl ether, and glycerin. Monoallyl ether, tetramethylol chlorhexanol diallyl monocrotyl ether, hexamethylol melamine diallyl dicrotyl ether,
Ethers having at least one hydroxyl group in the molecule such as hexanetriol diallyl ether, pentaerythritol diallyl crotyl ether, tetramethylolcyclohexanol triallyl ether, tetramethylolcyclohexanone diallyl ether, and hexamethylolmelamine tetraallyl ether are used. As mentioned above, this component is a component for imparting air-drying properties to the unsaturated polyester obtained, and is usually used in an amount of 0.1 mol or more, particularly 0.3 mol or more, per 1 mol of polybasic acid. Desirably, if the amount is less than 0.1 mol, air drying properties will be insufficient. The upper limit is possible up to the reaction limit.

The above-mentioned unsaturated polyester may be modified by incyanate modification, silicone modification, urethane modification, or the like. That is, the unsaturated polyester used for curing in the present invention includes a modified product.

The unsaturated polyester obtained by reacting each of the above components is
Usually, it is put to practical use as a solution of cross-linkable hexamer.

Examples of crosslinking monomers include styrene, vinyltoluene,
Monochlorostyrene, α-methylstyrene, diallyl phthalate, triallyl cyanurate, acrylic ester, methacrylic ester, methacrylic glycidyl,
2-hydroxy methacrylate glycidyl ether, vinyl acetate, vinyl chloride, methylene bisacrylamide,
Divinylbenzene, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate,
Diethylene glycol diacrylate, neopentyl glycol diacrylate, 1,6-hexanediol diacrylate, vinylcyclohexene monooxide,
Examples include known crosslinkable tops for unsaturated polyesters such as tung oil, linseed oil, soybean oil, cottonseed oil, safflower oil, and coconut oil.

In addition, a 7-duct form of polyisocyanate and polyhydric alcohol can also be used together with the crosslinking monomer.

As the curing catalyst, any of the following may be employed: (D) A combination of a radical polymerization initiator and a metal soap, (B) A combination of a radical polymerization initiator and an amine or an amine salt.

(2) As a radical polymerization initiator in Iz.

Methyl ethyl ketone peroxide, cyclohexanone peroxide, cumene hydroperoxide, benzoyl peroxide, dicumyl peroxide,
Butyl perbenzoate, etc. Metallic soaps in ■ include cobalt octenoate, cobalt naphthenate, manganese octenoate, manganese naphthenate, etc.; amines or amine salts in ■ include dimethylaniline,
Amines such as diethylaniline, dimethyl-p-)uidine, methyl-β-hydroxyethylaniline, di-β-hydroxyethylaniline, di-β-hydroxyethyl-p-toluidine, methylaniline, methyl-P-toluidine, Salts such as hydrochloric acid, acetic acid, and phosphoric acid are used.

In the present invention, when using the above-mentioned curing catalyst, it is essential that a sulfinate salt be present.

As the sulfinate, benzenesulfine m, p-
Toluenesulfine is harsh, β-naphthalenesulfine is ugly,
Sodium salts, calcium salts, strontium salts, ammonium salts, triethylammonium salts, N,N-dimethyl-p- of sulfinic acids such as styrene sulfinic acid
1. Salts such as luidine salt can be cited.

The amount of polymerization catalyst used in the crosslinkable monomer solution of unsaturated polyester can be varied, but the radical polymerization initiator is about 0.2 to 3% by weight, and the metal soap or amine (salt) is about 0.1 to 2% by weight. Often choose from a range of degrees.

The amount of the sulfinate salt to be used in the unsaturated polyester crosslinking monomer solution is selected from a range of about 0.05 to 2% by weight, preferably from 0.2 to 1.5% by weight. If the amount used is too small, the effect of the addition will be poor, while if the amount used is too large, the pot life will be extremely short, resulting in poor workability.

In the coating stage, pigments or fillers (titanium white, cyanine blue, chrome yellow, watching red, red iron oxide, carbon black, graphite, aniline black, manganese blue, iron black, ultramarine blue) are added as necessary.

Hansa red, chrome yellow, chrome green,
Calcium carbonate, kaolin, clay, talc, mica,
Alumina, asbestos powder, fine silica, barium sulfate,
Litopone, gypsum, barite, zinc stearate, etc.), leveling agents (silicone, cellulose acetate phthalate, surfactants, etc.), diluents (ethyl acetate, toluene, xylene, methanol, ethanol, butanol, acetone, methyl isobutyl ketones, methyl ethyl ketone, cellosolves, diacetone alcohol, etc.), thermoplastic resins such as trocellulose, vinyl chloride-vinyl acetate copolymer, vinyl acetate resin, acrylic resin, butylated melamine, butylated urea, etc.), greening inhibitors ( Known additives such as phosphoric acid, phosphorous acid, tartar alcohol, etc.), air drying aids (oils and fats, paraffin wax, etc.) can be blended.

EXAMPLES Next, the method of the present invention will be explained in more detail by way of examples. Hereinafter, "%" means % by weight.

Example 1 In a flask equipped with a stirrer, a gas inlet tube and a reflux condenser, 1.0 mol of maleic anhydride, 0.5 mol of propylene glycol, 0.25 mol of diethylene glycol, 0.25 mol of triethylene glycol and triallyl were added. Add 0.2 mol of pentaerythritol, and further add 3% xylene and 0.02% Hytroki/7 (polymerization inhibitor).
(the amount charged is based on the total amount of condensation components), a linear combination reaction was carried out at a temperature of 200°C for 5 hours while blowing nitrogen gas, and then the reaction was continued for 1 hour at 150°C under reduced pressure, and xylene was added. Distilled away.

The thus obtained air-drying unsaturated polyester having an acid value of 20 KOHmg/g was diluted with styrene monomer to obtain a resin liquid having a solid content of 70% and a viscosity of 2000 cps/20°C.

After adding 30 parts of styrene monomer to 100 parts of this resin liquid and diluting it to a spray viscosity, octene-cobalt (
Octex Go, manufactured by Nihon Kagaku Sangyo Co., Ltd., 8% co/
Held content) 0.5%, methyl ethyl ketone peroxide (Perme Nku N manufactured by Nippon Oil & Fats Co., Ltd.) 1.
A clear paint was prepared by mixing 0% and 0.5% of sodium benzenesulfinate, sprayed on wood, and cured at room temperature. The results are shown in Table 1.

Comparative Example 1 A paint was prepared by YA in the same manner as in Example 1, except that the addition of sodium benzenesulfinate was omitted, and the paint was spray-coated onto a wooden material and cured at room temperature.

The results are also shown in Table 1.

Table 1 Note: Internal curing speed was evaluated according to JIS K-Ei901.

Storage stability 1: Measured on samples to which only methyl ethyl ketone peroxide was not added.

The following can be understood from the results in Table 1.

(a) By coexisting with a sulfinate salt, the curing time can be significantly shortened without reducing the pot life if the amount of curing catalyst used is the same.

(b) If the curing time is to be kept the same by coexisting a sulfinate, the amount of curing catalyst used can be reduced, and the pot life can therefore be extended.

Examples 2 to 3 Experiments were conducted in the same manner as in Example 1, except that calcium benzenesulfinate CXm (Example 2) and ammonium benzenesulfinate (Example 3) were used in place of sodium benzenesulfinate.

The results are shown in Table 2.

Table 2 Example 4 Into a flask equipped with a stirrer, a gas inlet tube, and a reflux condenser, 0.7 mol of maleic anhydride, 0.3 mol of tetrahydrophthalic anhydride, 0.5 mol of propylene glycol, and 0.25 mol of diethylene glycol were added. In addition, 3% xylene and 0.02% hydroquinone (polymerization inhibitor) were added (each amount is based on the total amount of condensation components), and the temperature was raised to 200°C while blowing nitrogen gas. The feeding reaction was carried out for 5 hours at °C.
The reaction was then continued at 150° C. for 1 hour under reduced pressure, and xylene was distilled off.

The thus obtained unsaturated polyester having an acid value of 1 BKOHmg/g was diluted with a styrene monomer to obtain a resin liquid having a solid content of 68% and a viscosity of 2100 cps/20°C.

After adding 30 parts of styrene monomer to 100 parts of this resin solution and diluting it to a spray viscosity, 0.3% of dimethyl-P-1 luidine, 1.0% of benzoyl peroxide and 0.1% of P-1 sodium sulfinate were added. Mix 5% to prepare a clear paint.

It was spray coated on wood and allowed to harden at room temperature.

The results are shown in Table 3.

Comparative Example 2 P-) A coating material was prepared in the same manner as in Example 4 except that the addition of sodium luenesulfinate was omitted, and the coating material was spray-coated onto a wooden material and cured at room temperature.

The results are also shown in Table 3.

Table 3 The storage stability was measured for samples to which only benzoyl peroxide was not added.

Effect of the invention

Claims (1)

[Claims] 1. A method for curing unsaturated polyester, which comprises coexisting a sulfinate salt when curing unsaturated polyester using a conventional method. 2. The coexisting amount of sulfinate is 0.05 to 0.05 to the total amount.
2% by weight. 3. The method according to claim 1, wherein the unsaturated polyester is an allyl group-containing air-drying unsaturated polyester.