JPS6222828A - Curable unsaturated alkyd and its production - Google Patents

Abstract

PURPOSE:To obtain the titled resin having excellent workability and water and chemical resistance, by reacting a specified epoxy resin with p-tert- butylphenol and esterifying this reaction product with an alpha,beta-unsaturated polybasic acid. CONSTITUTION:An epoxy resin of formula I is reacted with p-tert-butylphenol in an amount to eliminate the epoxy groups of this epoxy resin to form a reaction product of formula II. The hydroxyl groups of this reaction product are esterified with an alpha,beta-unsaturated polybasic acid or its anhydride to produce a curable unsaturated alkyd of the formula, wherein R1 and R2 are each H or methyl, n is 0-2 and m is 2-20. The reactant ratio of the epoxy resin to the p-tert-butylphenol is preferably 0.5-1 equivalent of the phenolic hydroxyl groups per equivalent of the epoxy groups.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention is a radical-curable material having a novel structure useful for various uses such as paints, adhesives, molding materials, and FRP.

This invention relates to a functional unsaturated alkyd and a method for producing the same.

[Conventional technology]

Currently, unsaturated polyester resins and vinyl ester resins are widely used as radical-curable resins that can be cured at room temperature.

However, as the uses of resins become more diverse, the performance required of the resins becomes more detailed and sophisticated, and it is often felt that existing resins are insufficient to meet these requirements. For example, in the case of gel coat, which is commonly used as a coloring and surface protection layer for FRP, there is a movement to improve water resistance, alkali resistance, and corrosion resistance against specific chemicals without increasing costs.

Vinyl ester resins have extremely excellent water resistance and chemical resistance, so of course they can be used for this purpose, and in fact, their boiling resistance itself is extremely good, so they are generally used as gel coats. However, there is a need for further improvements in the workability required for gel coats, such as sprayability, thixotropy, and no color separation, and in line with these expectations, efforts for improvement continue. However, the desired results have not been achieved at this stage.

On the other hand, as for unsaturated polyester resin, C■ is a bisphenol polyester represented by the following formula.

Styrene bath liquid is popular for its good workability and has become the mainstream gel coat for bathtubs. However, it has the disadvantage that its hot water resistance is inferior to that of vinyl ester resin, and it does not meet high requirements.

[Problem that the invention seeks to solve]

As a result of intensive research aimed at improving the various drawbacks of these existing resins, the present inventors discovered that an unsaturated alkyd with a new structure represented by the following general formula was found to be at least as good as these existing resins in terms of water resistance and chemical resistance. The present inventors have discovered that they have the same or better properties and are also superior in workability, and have completed the present invention.

[Means for solving problems]

That is, the present invention provides a curable material represented by the general formula % (wherein R4 and .R2 each represent hydrogen or a methyl group, n is O to 2, and m is an integer from 2 to 20). to provide highly unsaturated alkyds.

Furthermore, the present invention involves reacting an epoxy resin represented by the general formula (%) with A tertiary butylphenol in an amount that eliminates the epoxy groups in the epoxy resin to form a reaction product C1.
) (hereinafter referred to as the margin), the hydroxyl group in the reaction product [I] is
-Providing a method for producing a curable unsaturated alkyd represented by the general formula (%), characterized by esterification with a β-unsaturated polybasic acid or its anhydride (where R1+ R2+ n and m are the same as above].

[Effect]

The unsaturated alkyd of the present invention has a novel structure represented by the above general formula, is bulky because it has a tertiary-butylphenooxymethylene group in the side chain, and has a small number of double bonds per molecular weight. Therefore, it is presumed that this has a favorable influence on the boiling resistance and heat distortion temperature of the resin. In addition, since the main chain of the unsaturated alkyd of the present invention is composed of repeating units in which bisphenol diglycidyl ether and α-β unsaturated polybasic acid are ester-bonded, it can be used as a styrene m-liquid like bisphenol type polyester. It is thought that it will have excellent workability when used. If the repeating unit is 2 to 20, it is a reed (equivalent to about 10,000 to 10,000 in terms of molecular weight), and if the repeating unit is smaller than 2, the resin will have poor curing properties, and if it is larger than 20, it will be difficult to carry out the present invention. Become.

The unsaturated alkyd according to the present invention can be used in paints, adhesives, It can be used for various purposes such as molding materials and FRP.

The method for synthesizing the unsaturated alkyd of the present invention is to use a bisphenol diglycidyl ether type epoxy resin. Examples include a method of reacting Shirahasharybutylphenol and then esterifying the hydroxyl group in the reaction product [I] with an α-β unsaturated polybasic acid or its anhydride. The flow is shown below using a typical example.

(Margin below) The epoxy resin used in the present invention is so-called.

It is of the phenyl glycidyl ether type, commonly known as the bisphenol type.

Example A type represented by the following general formula synthesized from Evahisphenol A and Shrimp Chlorohito IJ 7 (the following is a blank space).N is preferably in the range from O to 2nd position, and there is no need to increase the number of repeating units.

Furthermore, a methylene-bisphenylglycidyl ether type epoxy resin commonly referred to as a bisphenol F type epoxy resin can also be used.

The reaction ratio of the phenolic hydroxyl resin and the nocturnal tertiary butylphenol is suitably between 1 equivalent and 0.5 equivalent of phenolic hydroxyl group per 1 equivalent of epoxy group.

If the amount is less than 0.5 equivalent, it is not preferable because it tends to be glued during esterification with an unsaturated polybasic acid or its acid anhydride.

During the reaction, tertiary amines that are generally used as curing accelerators for epoxy resins, such as benzyldimethylamine, tris(dimethylamino)phenol, or quaternary amines, are used.
The use of grade ammonium salts and the like is highly effective in terms of promoting the reaction.

Examples of the α-β unsaturated polybasic acid or its acid anhydride used in the present invention include maleic anhydride, maleic acid, and fumaric acid. At that time, it can also be modified with a small amount of saturated polybasic acid.

Esterification is carried out in the usual manner, ie in an inert gas stream.

It is carried out at a temperature of about 180 to 220°C.

The unsaturated alkyds obtained by esterification are styrene, vinyltoluene, and diallyl phthalate.

It can be dissolved in copolymerizable monomers such as diallyl terephthalate and methacrylic acid esters and provided for various uses.

At this time, in order to prevent gluing, a small amount of commonly used polymerization inhibitors such as polyhydric phenols and quinones (
0.01 to 0.5 phr) must be added.

It goes without saying that fillers, reinforcing materials, colorants, mold release agents, polymers, etc. can be used in combination, depending on the needs of the application.

〔Example〕

Next, examples will be shown below to help understand the present invention. In the examples, parts indicate parts by weight.

Example 1 In an 11-cell iR rubble flask equipped with a stirrer, fractionation condenser, thermometer, and gas inlet tube, as an epoxy resin,
370g of Yuka Shell's Epicote 827, 270g of tert-butylphenol! j (ratio of epoxy group to phenolic hydroxyl group is 1:0.9) and 1.5 g of benzyldimethylamine are charged and heated. When the temperature exceeds 110°C, it rapidly generates heat, so cool it and the temperature reaches 160°C or higher. This was prevented.

When the reaction was then carried out at 150 to 160° C. for 5 hours, infrared analysis showed that the free epoxy groups had completely disappeared (see Figure 1).

Next, add 110 g of fumaric acid and add 200 g of fumaric acid to
When heated to 10°C for 6 hours, the acid value was 11.4, so hydroquinone was 0°18! j and poured into a metal vat to solidify. An unsaturated alkyd (A) having a yellowish brown color and a melting point of about 120°C was obtained.

The infrared absorption spectrum is shown in FIG. The average molecular weight was approximately 5,000.

Grind 100 parts of unsaturated alkyd (A), add 100 parts of styrene to it, and heat and stir at 60-70°C to obtain unsaturated polyester resin (B), which has a cloudy Gardner color number of 1-2 and a viscosity of 10. , 7 poise.

100 parts of unsaturated polyester resin (B), 22 parts of methyl ethyl ketosonosoxy, 2 parts of cobalt naphthenate
The system in which 50% of the total amount was added was glued in 80 minutes, and the maximum temperature reached 122° C. while slowly generating heat.

The heat distortion temperature of the cast product was 106°C.

As a result of a continuous boiling test performed on a casting plate measuring 5 cm x 5 cm and 3 ttm thick, no abnormality in appearance was observed even after 2000 hours of boiling, indicating excellent water resistance.

Further, in a continuous boiling test using a 10% caustic soda aqueous solution, no abnormalities were observed for up to 500 hours, and similarly, extremely good alkali resistance was exhibited.

Example 2゜11 cell equipped with a stirrer, a fractionating condenser, a gas inlet pipe, and a thermometer) J? Epicoat 807 from Yuka Shell Co., Ltd. is used as a bisphenol F type epoxy resin in Syllable Lasco.
3401, Nogulatatiarybutylphenol 24
0# (ratio of epoxy group to phenolic hydroxyl group is 1:0.8), and 1.5 g of trimethylbenzylammonium chloride are charged. When heated, heat starts rapidly after reaching 110°C, so it is cooled to 160°C. I kept it below.

When maintained at 150-160°C for 5 hours, free epoxy groups completely disappeared as a result of infrared analysis.

Next, add 98 g of maleic anhydride and heat at 200-215°C.
After 6 hours of esterification in an inert gas stream, the acid value was 9.6.
So, hydroquinone 0.1! i was added, poured into a metal punt, and solidified.

An unsaturated alkyd (C) having a yellowish brown color and a melting point of about 110°C was obtained. The average molecular weight was about 5,000.

An unsaturated polyester resin obtained by pulverizing 100 parts of unsaturated alkyd (C) and dissolving it in 110 parts of p-methylstyrene by heating at 60 to 70°C (color number: 300, viscosity: 18.3) It was Poise.

100 parts of unsaturated polyester resin (I), 2 parts of methyl ethyl ketone e-oxide, 1 part of cobalt naphthenate
The system containing 0.2 parts of dimethylaniline and 0.2 parts of dimethylaniline slowly generates heat after delification at room temperature for about 50 minutes, and the maximum exothermic temperature is 1 part.
The temperature reached 31°C.

The heat distortion temperature of the cast product was 110°C.

[Brief explanation of drawings]

FIG. 1 shows an infrared spectrum of the reaction product of the epoxy resin obtained in Example 1 and /J tertiary butylphenol. FIG. 2 shows an infrared spectrum of the unsaturated alkyd of the present invention obtained by reacting the above reaction product with fumaric acid.

Claims (2)

[Claims] (1) Curable unsaturated alkyd substantially represented by the following general formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [However, R_1 and R_2 each represent hydrogen or a methyl group, and n is 0 to 2. , m is an integer from 2 to 20. (2) An epoxy resin represented by the general formula is reacted with paratertiary butylphenol in an amount that eliminates the epoxy groups in the epoxy resin to produce a reaction product [
I] ▲There are mathematical formulas, chemical formulas, tables, etc.▼ is produced, and then the hydroxyl group in the reaction product [I] is esterified with an α-β unsaturated polybasic acid or its anhydride. A method for producing a curable unsaturated alkyd represented by the general formula ▲ There are numerical formulas, chemical formulas, tables, etc. ▼ [However, R_1, R_2, n and m are the same as above].