JP2551602B2 - Method for producing unsaturated polyesterimide resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing an unsaturated polyesterimide resin excellent in heat resistance and air drying property.

[Conventional technology]

BACKGROUND ART Unsaturated polyesterimide resins have been used as varnishes by adding diluting monomers and additives, and have been used for coil impregnation. As such an unsaturated polyester imide resin, an unsaturated polyester imide resin containing an imide compound has been proposed for the purpose of improving heat resistance (JP-A-45-28509).

Furthermore, for the purpose of improving heat resistance, the imide group-containing dicarboxylic acid and the imide group-containing alcohol are 10 to 65% by weight.
An unsaturated polyester imide resin containing the same has been proposed (JP-A-53-127594).

Then, for the purpose of improving curability and heat resistance, 5
An unsaturated polyesterimide resin containing at least one of a monovalent carboxylic acid containing a member imide ring and a monohydric alcohol containing a 5-membered imide ring has been proposed (JP-A-51-89592).

Further, for the purpose of improving heat resistance and mechanical properties, 1
An unsaturated polyester imide resin containing a divalent imide group-containing alcohol and an imide group-containing oxycarboxylic acid compound as constituent components has been proposed (JP-A-56-129217).

Further, for the purpose of improving heat resistance, mechanical properties and flexibility, an unsaturated polyester imide resin containing a monovalent imide group-containing alcohol, an imide group-containing oxycarboxylic acid compound and a vegetable oil or its fatty acid as components is also proposed. (JP-A-56-129218).

However, these unsaturated polyester imide resins progress the curing reaction of the resin by radical polymerization, but this radical polymerization is subjected to a polymerization inhibitory action by oxygen in the air, so that an unpolymerized product remains on the resin surface in contact with air. This will cause stickiness. Therefore, unsaturated polyester imide resin used for coil impregnation, etc., which is cured in the state of contacting with air, has a metal varnish such as cobalt octenoate and manganese naphthenate, or
By adding and containing drying oils such as tung oil, flaxseed oil and its derived fatty acids, air drying property is improved and stickiness on the resin surface is improved.

[Problems to be solved by the invention]

However, adding the drying oils and the like at the same time as the resin forming material shortens the storage period of the resin itself,
The addition of metal salts such as cobalt and manganese accelerates the deterioration of the resin cured product due to oxidation, so the heat resistant insulation life is shortened for insulation applications such as coil impregnation, and in other applications the mechanical strength due to thermal deterioration is shortened. The problem is that the value drops sharply.

The present invention has been made in view of such circumstances,
It is an object of the present invention to provide a method for producing an unsaturated polyester imide resin, which is excellent in heat resistance of the unsaturated polyester imide resin, flexibility of a resin cured product and surface dryness.

[Means for solving problems]

In order to achieve the above object, the method for producing an unsaturated polyesterimide resin of the present invention is such that the following component (A) is prepared in advance, and then a polyhydric alcohol containing the component (A) as a main component and an unsaturated diamine are prepared. A carboxylic acid, a monohydric alcohol containing the following component (B) as a main component, and optionally a saturated dicarboxylic acid are reacted. (A) A fatty acid-modified polyhydric alcohol obtained by reacting 0.8 to 1.2 equivalents of fatty acid per 1.0 equivalent of trihydric alcohol.

(B) 2-Tetrahydrophthalimide ethanol.

[Work]

That is, the present inventors have conducted extensive research to impart heat resistance to unsaturated polyester imide resins, flexibility and surface dryness to cured resin products, and as a result, prepared the above-mentioned special polyhydric alcohol in advance and then By using a polyhydric alcohol containing the special polyhydric alcohol as a main component, an unsaturated divalent carboxylic acid, the above-mentioned special monohydric alcohol, and optionally a saturated divalent carboxylic acid, the intended purpose can be achieved. I found out what I could do and arrived at this invention.

The unsaturated polyesterimide resin according to the present invention is obtained by using a polyhydric alcohol (a), an unsaturated divalent carboxylic acid (b), a monohydric alcohol (c), and optionally a saturated divalent carboxylic acid (d). To be

Examples of the polyhydric alcohol (a) include trihydric alcohols.
0.8 to 1.2 equivalents of fatty acid are reacted per 1.0 equivalent, and one of the three hydroxyl groups of the trihydric alcohol containing one fatty acid-modified polyhydric alcohol as a main component is used. Thus, dihydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol and neopentyl glycol are used together. In addition, in the present invention, the term “main component” is intended to include a case where the entire component is composed of only the main component. And as said trihydric alcohol, tris (2-hydroxyethyl) isocyanurate is used especially suitably. The fatty acid used for the above modification is not particularly limited, but a fatty acid derived from a drying oil such as tung oil and flaxseed oil is preferable. The amount of these polyhydric alcohols used is preferably set within the range of 25 to 70% by weight with respect to the resin component.
That is, if it is less than the above range, the flexibility of the resin cured product and the drying property of the resin surface are deteriorated, and if it exceeds the above range, the mechanical strength of the resin cured product is decreased because the molecular weight of the unsaturated polyester becomes small. .

Examples of the unsaturated divalent carboxylic acid (b) include maleic anhydride, fumaric acid and the like. The amount of the unsaturated divalent carboxylic acid used is the amount of the resin components [(a) to (d) charged]. It is preferable to set it in the range of 10 to 40% by weight based on the total amount].

As the monohydric alcohol (c), one having 2-tetrahydrophthalimidoethanol represented by the following structural formula as a main component is used.

It is advantageous to set the content of the 2-tetrahydrophthalimidoethanol in the range of 10 to 70 mol%, preferably 15 to 50 mol% of the total alcohol added. That is, when it is less than 10 mol%, the heat resistance of the resin becomes insufficient, and when it exceeds 70 mol%, the strength of the resin cured product decreases.

Further, as the saturated divalent carboxylic acid (d) to be optionally reacted, phthalic acid, isophthalic acid, terephthalic acid, adipic acid, tetrahydrophthalic anhydride, etc.,
It is used as a flexibility-imparting component for the resin within the range of 5 to 30% by weight based on the resin component.

Production of such unsaturated polyester imide resin,
For example, it can be performed as follows. That is,
A trihydric alcohol and a drying oil type fatty acid are previously reacted to prepare a fatty acid-modified polyhydric alcohol. Then, tetrahydrophthalic anhydride and monoethanolamine are added and reacted to produce a monohydric alcohol consisting of 2-tetrahydrophthalimidoethanol. Then, a polyhydric alcohol such as ethylene glycol and an unsaturated carboxylic acid such as maleic anhydride and, if necessary, a polymerization inhibitor are added thereto and heated to react to prepare an unsaturated polyesterimide resin. An unsaturated polyesterimide resin varnish is manufactured by adding a diluting monomer to the resin thus obtained to reduce the viscosity.

As the polymerization inhibitor, hydroquinone, butylhydroxyanisole, benzoquinone and the like are used.

As the diluent monomer, styrene, vinyltoluene, diallyl phthalate, diallyl isophthalate, acrylic ester, methacrylic ester and the like are used. The amount of the diluted monomer added is preferably set within the range of 40 to 185% by weight with respect to the obtained unsaturated polyesterimide resin.

〔The invention's effect〕

As described above, since the unsaturated polyester imide resin obtained by the present invention has a constituent part derived from 2-tetrahydrophthalimide ethanol and a constituent part derived from a fatty acid-modified polyhydric alcohol in the resin, surface drying Excellent in heat resistance and heat resistance, and also excellent in flexibility. Therefore, it is suitable not only for coil impregnation of electrical equipment but also for laminated plate, reinforced plastic (FRP) and adhesive, and has excellent surface drying property. The process time can be shortened.

 Next, examples will be described together with comparative examples.

Example 1 In a four-necked flask (volume 1) equipped with a rectification tube, a temperature controller, a stirrer and a heating device, 130 g (0.5 mol) of tris (2-hydroxyethyl) isocyanurate and 140 g (0.5 mol) of linseed oil fatty acid were added. Mol) was added and dehydration reaction was carried out at 220 ° C. for 3 hours, followed by cooling and charging with 228 g of tetrahydrophthalic anhydride and 92 g of monoethanolamine, followed by reaction at 200 ° C. for 3 hours, then ethylene glycol 19 g, maleic anhydride 13
8 g of hydroquinone and 0.3 g of hydroquinone were added and reacted at 190 ° C. for 6 hours to obtain an unsaturated polyesterimide resin having an acid value of 20. Further, 82 parts of styrene was added to 100 parts by weight of the above resin (hereinafter abbreviated as “part”) for dilution, and an unsaturated polyesterimide resin varnish having a desired resin solution viscosity of 2.1 poise (25 ° C.) was obtained.

[Example 2] Styrene was replaced by diallyl isophthalate. Otherwise in the same manner as in Example 1, an unsaturated polyesterimide resin varnish having an acid value of 20 and a resin solution viscosity of 26 poise (25 ° C.) was obtained.

[Examples 3 to 6] The composition of each raw material was changed to the ratio shown in Table 1 below,
Further isophthalic acid was added. Other than that was carried out similarly to Example 1, and obtained the unsaturated polyester imide resin varnish of the acid value and resin solution viscosity shown in Table 1 below.

[Example 7] 82 parts of styrene was replaced with 100 parts of diallyl phthalate.
Otherwise in the same manner as in Example 3, acid value 18 and resin solution viscosity 1
An 8 poise (25 ° C.) unsaturated polyesterimide resin varnish was obtained.

For 100 parts of the products of Examples 1 and 2 above, t-
Add 2 parts of butyl perbenzoate, 0.3 × 50 × 180mm
It was applied to the iron plate of No. 3 and cured at 150 ° C. for 15 minutes to examine the stickiness of the resin.

Next, 3 g of a conventional polyester resin varnish was collected on a glass shear having a diameter of 60 mm as all the example products and comparative products, cured at 150 ° C. for 20 hours, and then left at 250 ° C. for 40 days to measure the weight loss rate. Table 2 shows the results.

From Table 2, it can be seen that the product of Example has a lower weight reduction rate than the conventional product, and thus has excellent heat resistance.

 ─────────────────────────────────────────────────── --- Continuation of the front page (56) Reference JP-A-51-89592 (JP, A) JP-A-56-129218 (JP, A) JP-A-56-129217 (JP, A) JP-A-53- 127594 (JP, A) JP-B-45-28509 (JP, B1)

Claims (3)

(57) [Claims] 1. A component (A) below is prepared in advance, and then a polyhydric alcohol containing the component (A) as a main component, an unsaturated divalent carboxylic acid, and a component (B) below as a main component are prepared. A process for producing an unsaturated polyesterimide resin, which comprises reacting a dihydric alcohol with a saturated divalent carboxylic acid in some cases. (A) 0.8 to 1.2 fatty acids per 1.0 equivalent of trihydric alcohol
A fatty acid-modified polyhydric alcohol obtained by reacting equivalent amounts. (B) 2-Tetrahydrophthalimide ethanol. 2. The method for producing an unsaturated polyesterimide resin according to claim 1, wherein the polyhydric alcohol is a combination of the component (A) and a dihydric alcohol. 3. The trihydric alcohol is tris (2-hydroxyethyl) isocyanurate.
Item 2. The method for producing an unsaturated polyesterimide resin according to Item 2.