JP2001081145A - Curing promoter for unsaturated polyester resin - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject curing promoter capable of giving colorless unsaturated polyester resins by combining a cobalt soap, a zinc soap and a calcium soap together. SOLUTION: This curing promoter is obtained by combining (A) a cobalt soap (e.g. cobalt naphthenate), (B) a zinc soap (e.g. zinc octoate) and (C) a calcium soap (e.g. calcium neodecanoate); wherein it is preferable that the amounts of the above components A to C to be included are 0.00005-0.0025 pt.wt., 0.00005-0.0025 pt.wt. and 0.00005-0.01 pt.wt., each based on 100 pts.wt. of an unsaturated polyester resin intended to produce, respectively. Further, this curing promoter is preferably incorporated with 0.01-10 pts.wt., based on an unsaturated polyester resin intended to produce, of either a β-diketone of formula I (R is an alkyl or aryl), β-keto acid ester of formula III or β-keto acid of formula III.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a curing accelerator which provides a transparent unsaturated polyester resin as a new composition.

[0002]

2. Description of the Prior Art Cobalt naphthenate and cobalt octylate, which are oil-soluble cobalt compounds, are considered to promote the generation of peroxide radicals, and are used as a curing agent for unsaturated polyester resins in terpene or xylene solutions. It has been used since ancient times.

An oil-soluble cobalt compound can quickly cure an unsaturated polyester resin by the synergistic effect of a peroxide, but the cured resin is colored pink, so that a color such as a display can be obtained. It was not suitable for the application in question.

However, if the cobalt concentration is reduced to such an extent that the coloring by cobalt does not become a problem, the curing time becomes extremely long, which is not practical. Therefore, various studies have been made on the improvement of the properties of the unsaturated polyester resin, including transparency and prevention of coloring.

Japanese Patent Publication No. 38-23314 discloses calcium (II) cobalt octoate, and Japanese Patent Publication No. 39-29195 discloses a vanadium compound and a sulfur compound capable of reducing.
No. -15434 discloses that the use of a β-keto acid ester of aluminum and a cobalt compound provides a colorless and transparent cured product and an effect of preventing the resin from being greened.

Further, an alkali metal compound is added to JP-B-42-23300, and a salt or phenol analog soluble in an amine, copper or zinc resin is added to JP-B-39-15436 and dissolved therein. Even if the elapsed time from the addition of the curing accelerator to the saturated polyester resin to the start of the curing of the unsaturated polyester resin by the addition of the organic peroxide becomes long, the curing time can be prevented from being delayed. That is, it is disclosed that the pot life (pot life) becomes longer.

[0007]

However, the above-mentioned method has problems in toxicity, odor and the like, and is currently hardly practically used. An object of the present invention is to provide a new curing accelerator useful for making the unsaturated polyester resin cured product transparent and preventing coloring in such a situation.

[0008]

Means for Solving the Problems As a result of intensive studies on this point, the present inventors have solved the problems of making the unsaturated polyester resin transparent and preventing coloring by combining cobalt soap, zinc soap and calcium soap. Reached.

That is, the present invention relates to (1) a curing accelerator for unsaturated polyester resin comprising cobalt soap, zinc soap and calcium soap, and (2) a cobalt soap of cobalt soap based on 100 parts of unsaturated polyester resin. The amount is 0.00005 to 0.0025 parts, the zinc content of the zinc soap is 0.00005 to 0.0025 parts, and the calcium content of the calcium soap is 0.00005 to
The curing accelerator for unsaturated polyester resin according to the above (1), which is used in an amount of 0.01 part, and (3) any one or two of β-diketone, β-keto acid, and β-keto acid ester The present invention relates to the curing accelerator for unsaturated polyester resins according to the above (1) or (2), wherein the above is added.

The unsaturated polyester resin referred to in the present invention is an unsaturated polyester resin obtained by an esterification reaction of a polybasic acid containing an α, β-unsaturated dibasic acid and a dihydric alcohol with the α, β-unsaturated polyester. It is dissolved in a monomer having an unsaturated bond copolymerizable with a saturated double bond. As a matter of course, a polymerization inhibitor or a solvent may be used in combination with the unsaturated polyester resin.

The curing accelerator of the present invention is not only an unsaturated polyester resin alone but also a mixture of unsaturated polyester resin with calcium carbonate, barium sulfate, clay metal powder, glass powder, colorant, and other powdery substances. Also, it can be similarly used for a material containing a fibrous substance such as glass fiber, plant fiber, synthetic fiber, mineral fiber and the like.

The organic peroxide used for the curing reaction of the unsaturated polyester resin includes, for example, benzoyl peroxide,
Examples thereof include di-t-butyl peroxide, di-t-butyl hydroperoxide, cumene hydroperoxide, methyl ethyl ketone peroxide, and methyl isobutyl ketone peroxide.

The metal soap used in the curing accelerator of the present invention is a metal fatty acid salt. Here, the fatty acid is a natural or synthetic saturated or unsaturated fatty acid having a main chain having 6 to 30 carbon atoms, or a mixture thereof.
Specifically, caproic acid, caprylic acid, capric acid, lauric acid, myristic acid, palmitic acid, stearic acid, isostearic acid, arachiic acid, behenic acid, oleic acid, linoleic acid, linoleic acid, resinoleic acid, 12
-Hydroxystearic acid, dimer acid, tall oil acid,
Examples thereof include naphthenic acid, neodecanoic acid, resin acid, and natural fatty acids containing these as a main component such as fish oil-hardened fatty acids and tallow hardened fatty acids. Specifically, as a cobalt soap, cobalt naphthenate, cobalt neodecanoate, cobalt octylate, and zinc soap are:
Zinc neodecanoate, zinc naphthenate, zinc octylate,
Examples of the calcium soap include calcium neodecanoate, calcium naphthenate, and calcium octylate. Since the fatty acid species of the metal soap has a great effect on the compatibility with the solvent, it is necessary to select in consideration of this point.

In the curing accelerator of the present invention, β-diketone, β-keto acid, β-diketone,
The keto acid ester is represented by the following general formula.

[0015]

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By mixing these with 0.01 to 10 parts, especially 0.1 to 5 parts with respect to 100 parts of the unsaturated polyester resin, β-diketone is converted into an organic peroxide by the action of metallic soaps. Β-diketones, which are considered to suppress harmful side reactions to the polymerization reaction that occurs when decomposing to form free radicals, are, for example, acetylacetone, β-keto acid, and β-keto acid esters, for example, β-diketone.
(Alkylcarbonyl) -acetic acid, β- (arylcarbonyl) -acetic acid and esters thereof are used. Specific examples of these include acetoacetic acid, propionylacetic acid, butyroylacetic acid, isobutyroylacetic acid, benzoylacetic acid and its methyl ester, ethyl ester, propyl ester, isopropyl ester, butyl ester, isobutyl ester, tertiary butyl ester and the like.

These additives may be contained in the metal soap solution (one-pack type) or may be added separately (two-pack type) when the resin is cured.

In the present invention, the ratio of cobalt soap, zinc soap and calcium soap to the unsaturated polyester resin is important. That is, a transparent and colorless cured unsaturated polyester resin can be obtained by using a metal soap having a specific range of the weight percent of cobalt, zinc, and calcium based on the unsaturated polyester resin. As the cobalt content increases, the curing time decreases, but the pink coloration increases. If the content of zinc or calcium is too high or too low, the curing time will be slow. Calcium also affects coloration, and becomes blue when the calcium content is high. Therefore, in order to obtain a colorless or nearly colorless unsaturated polyester resin cured product, the cobalt content is set to 0.00005 to 0.0025 parts, preferably 0.0001 to 0.002 parts per 100 parts of the unsaturated polyester resin. Parts, zinc content is 0.00005 to 0.0025 parts, preferably 0.0005 parts.
01-0.002 parts, calcium content 0.000
05 to 0.01 parts, preferably 0.0001 to 0.00
It must be 5 parts.

The method for producing cobalt soap, zinc soap and calcium soap may be prepared by mixing metal soaps separately produced, or by reacting an inorganic salt and a fatty acid in one batch to produce a metal soap. It can be manufactured at the same time.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be specifically described below with reference to examples and comparative examples. The curing speed was such that the composition shown in Table 1 was thoroughly stirred, then transferred to a 100 ml beaker, immersed in a water bath at 25 ° C. having sufficient heat retention capacity, and no thread was pulled when the glass rod was pulled up. Was determined as the end point, and the time was compared as the gel time. The color of the unsaturated polyester resin after curing was judged visually. Table 2 shows the composition of the metal soap.

[0021]

[Table 1]

Incidentally, cobalt naphthenate was used as the cobalt soap, zinc octylate was used as the zinc soap, and calcium neodecanoate was used as the calcium soap.

Example 1 Cobalt naphthenate, zinc octylate and calcium neodecanoate were prepared using 100 g of an unsaturated polyester resin and metal soap manufactured by Nikko CS Chemical Co., Ltd.
0.5 g of a turpentine solution of metallic soap (0.2% by weight of cobalt naphthenate, 0.2% by weight of zinc octylate, 0.2% by weight of calcium neodecanoate) added to give the composition shown in Table 2 After stirring with a bar, 1.0 g of peroxide was added and stirred well. The time when the gelation started was 14 minutes and 42 seconds, and the unsaturated polyester resin after curing was colorless.

Examples 2 to 5 and Comparative Examples 1 to 3 were carried out in the same manner as in Example 1 except that the composition of the metal soap was different.

[0025]

[Table 2]

[0026]

As described above, when the unsaturated polyester resin is polymerized and cured by a peroxide catalyst, the use of the accelerator combining the cobalt soap, the zinc soap and the calcium soap of the present invention makes it possible to obtain a colorless unsaturated resin. A polyester resin can be obtained quickly.

Claims (3)

[Claims] 1. A curing accelerator for unsaturated polyester resin comprising cobalt soap, zinc soap and calcium soap. 2. A cobalt soap having a cobalt content of 0.00005 based on 100 parts of the unsaturated polyester resin.
0.0025 parts, zinc content of zinc soap is 0.00
The curing accelerator for unsaturated polyester resins according to claim 1, wherein the curing agent is used in an amount of 005 to 0.0025 parts and a calcium soap having a calcium content of 0.00005 to 0.01 parts. (3) a β-diketone, β-keto acid, β
The curing accelerator for unsaturated polyester resins according to claim 1, wherein one or more of keto acid esters are added.