JP2514017B2 - Method for producing unsaturated epoxy ester resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing an unsaturated epoxy ester resin which gives a cured product having excellent heat resistance, water resistance and weather resistance.

More specifically, it relates to a method for producing an unsaturated epoxy ester resin using an epoxy resin having an ether bond in the molecule.

[Prior Art] Conventionally, unsaturated epoxy ester resins are thermosetting,
Taking advantage of features such as photocurability, as a raw material for paints for woodworking, metal and plastic, and as a resin for FRP,
It is widely used as a sealing agent for electronic parts, as a resin for printing ink and as a resin raw material for insulating paint.

This unsaturated epoxy ester resin is disclosed in JP-B-44-3147.
2, JP-B-45-1465, JP-B-45-15988, JP-B-45-4006
9, as described in JP-A-48-28599, an epoxy compound and an unsaturated monocarboxylic acid may be used, if necessary, part or most of the unsaturated monocarboxylic acid is a saturated monocarboxylic acid or a saturated polycarboxylic acid. Acid, saturated polycarboxylic acid anhydride, unsaturated polyvalent carboxylic acid, unsaturated polycarboxylic acid anhydride, substituted with one or more selected from unsaturated alkyd having a terminal carboxyl group, a reaction catalyst Further, it was produced by allowing a polymerization inhibitor, a solvent or a polymerizable monomer to coexist as necessary and performing a heating reaction.

[Problems to be Solved by the Invention] Generally used epoxy compounds are produced by a reaction of bisphenol and epichlorohydrin, that is, so-called EPB type epoxy resin, and novolac type epoxy resin produced by a reaction of novolac phenol and epichlorohydrin. It has a benzene ring in its isomolecular skeleton.

A cured product of an unsaturated epoxy polyester resin obtained by using these epoxy resins has drawbacks such as poor weather resistance and lack of transparency due to the benzene skeleton.

Aliphatic epoxy resins, epoxidized vegetable oils and the like are used as other epoxy resins, but they have the drawback of lacking heat resistance and toughness.

In view of such a situation, as a result of intensive investigations by the present inventors, a cured product having excellent heat resistance, weather resistance and hardness by using the novel epoxy resin disclosed in JP-A-60-16675 is obtained. It has been found that an unsaturated epoxy polyester resin can be obtained, which has led to the present invention.

[Means for Solving the Problems] That is, the present invention provides “(A) an epoxy resin represented by the following general formula (I). [However, in the general formula (I), R ¹ is a residue excluding active hydrogen in an organic compound having ¹ active hydrogen, n 1, n 2
... nl is 0 or an integer of 1 to 100, and the sum thereof is 1 to 100, l represents an integer of 1 to 100, B is an oxycyclohexane skeleton, and is represented by the following formula: However, X is However, R ² is H, an alkyl group, an alkylcarbonyl group,
An arylcarbonyl group, which is one of Containing at least one or more in the resin of formula (I)] and (B) unsaturated monocarboxylic acid and optionally (C) saturated monocarboxylic acid, saturated polycarboxylic acid, saturated polycarboxylic anhydride, Two components (A) and (B) consisting of one or more selected from unsaturated polycarboxylic acids, unsaturated polycarboxylic anhydrides, and unsaturated alkyds having a terminal carboxyl group, or ( It is characterized in that three components of A), (B) and (C) and optionally (D) a polymerization inhibitor, a solvent or a polymerizable monomer are heated and reacted in the presence of a reaction catalyst. Method for producing unsaturated epoxy ester resin. It is.

Next, the method for producing the unsaturated epoxy ester resin of the present invention will be described in detail.

In the epoxy resin represented by the formula (I) which is the component (A) in the production method of the present invention, R ¹ is a residue of the organic compound having active hydrogen from which active hydrogen is removed, Examples of the organic substance having hydrogen include alcohols, phenols, carboxylic acids, amines and thiols. The alcohol may be a monohydric alcohol or a polyhydric alcohol.

For example, methanol, ethanol, propanol, butanol, pentanol, hexanol, aliphatic alcohols such as octanol, aromatic alcohols such as benzyl alcohol, ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol,
1.3 butanediol, 1.4 butanediol, pentanediol, 1.6 hexanediol, neopentyl glycol, oxypivalic acid neopentyl glycol ester, cyclohexanedimethanol, glycerin, diglycerin, polyglycerin, trimethylolpropane, trimethylolethane, pentaerythritol, There are polyhydric alcohols such as dipentaerythritol.

Examples of phenols include phenol, cresol, catechol, pyrogallol, hyroquinone, hydroquinone monomethyl ether, bisphenol A, bisphenol F, 4,4'-dihydroxybenzophenone, bisphenol S, phenol resin, and cresol novolac resin.

Examples of carboxylic acids include formic acid, acetic acid, propionic acid, butyric acid, fatty acids of animal and vegetable oils, fumaric acid, maleic acid, adipic acid, dodecane diacid, trimellitic acid, pyromellitic acid, polyacrylic acid, phthalic acid, isophthalic acid, and terephthalic acid. Acids and the like.

Further, compounds having both a hydroxyl group and a carboxylic acid, such as lactic acid, citric acid and oxycaproic acid, can also be mentioned.

Examples of amines include monomethylamine, dimethylamine, monoethylamine, diethylamine, propylamine, monobutylamine, dibutylamine, pentylamine, hexylamine, cyclohexylamine, octylamine, dodecylamine, 4,4′-diaminodiphenylmethane, isophoronediamine, There are toluenediamine, hexamethylenediamine, xylenediamine, diethylenetriamine, triethylenetetramine, ethanolamine and the like.

Examples of the thiols include mercaptos such as methyl mercaptan, ethyl mercaptan, propyl mercaptan, and phenyl mercaptan, polyhydric alcohol esters of mercaptopropionic acid or mercaptopropionic acid, such as ethylene glycol dimercaptopropionic acid ester, trimethylolpropane trimercaptopropionic acid penta. Examples thereof include erythritol pentamercaptopropionic acid.

In addition, as the compound having active hydrogen, polyvinyl alcohol, polyvinyl acetate partial hydrolyzate, tempun, cellulose, cellulose acetate, cellulose acetate butyrate, hydroxyethyl cellulose,
There are acrylic polyol resin, styrene allyl alcohol copolymer resin, styrene-maleic acid copolymer resin, alkyd resin, polyester polyol resin, polyester carboxylic acid resin, polycaprolactone polyol resin, polypropylene polyol, polytetramethylene glycol, and the like.

The compound having active hydrogen may have an unsaturated double bond in its skeleton, and specific examples thereof include allyl alcohol, acrylic acid, methacrylic acid, 3-cyclohexenemethanol, tetrahydrophthalic acid and the like. is there.

The unsaturated double bonds in these compounds can also be in the structure in which they are epoxidized.

Any compound having these active hydrogens can be used, and two or more kinds of them may be mixed.

N1 in general formula (I), n2 ... nl is 0 or the integer of 1-100, respectively, and the sum is 1-100. When it is 100 or more, the resin has a high melting point, is difficult to handle, and cannot be practically used. l represents an integer of 1 to 100.

Of the substituents X of B in the general formula (I), It is essential to include at least one or more in the resin, but the more the more, the more preferable. In particular, However, the smaller R < ² > is any one of H, an alkyl group, an alkylcarbonyl group, and an arylcarbonyl group, the more preferable.

That is, in the epoxy resin represented by the general formula (I), the substituent X is Is the main one.

The epoxy resin represented by the general formula (I), which is the component (A) in the method for producing an unsaturated epoxy ester resin of the present invention, is prepared by using the compound having active hydrogen as an initiator.
It is produced by epoxidizing a polyether compound obtained by ring-opening polymerization of vinylcyclohexene oxide, that is, a polyether compound having a vinyl group side chain and an oxycyclohexane skeleton with peracetic acid, hydrogen peroxide or the like.

4-Vinylcyclohexene oxide is produced by partially epoxidizing 4-vinylcyclohexene obtained by the Diels-Alder reaction of butanediene with peracetic acid or hydrogen peroxide.

A catalyst is preferably used when ring-opening polymerization of 4-vinylcyclohexene oxide is initiated with a compound having active hydrogen as an initiator. Examples of the catalyst used in the reaction include amines such as methylamine, ethylamine, propylamine and piperazine, organic bases such as pyridine and imidazole, quaternary ammonium salts such as tetrabutylammonium bromide, formic acid, acetic acid and propionic acid. organic acids, alcoholates of alkali metals such sulfuric acid, and inorganic acids, sodium methylate such as hydrochloric acid, KOH, an alkaline such as _{NaOH, BF 3, ZnCl 2,} AlCl 3, SnCl Lewis acid or its complexes such as ₄ Examples thereof include organic metal compounds such as triethylaluminum and diethylzinc.
The amount of catalyst varies depending on the type, but is 0 for the starting material.
It can be used in the range of 01 to 10%, preferably 0.1 to 5%. The reaction temperature is -20 to 200 ° C, preferably 0 ° C to 1
20 ° C. The reaction can also be carried out using a solvent.

A solvent having active hydrogen cannot be used as the solvent.

That is, ketones such as acetone, methyl ethyl ketone and methyl isobutyl ketone, aromatic solvents such as benzene, toluene and xylene, ethers, aliphatic hydrocarbons and esters can be used.

Now, the epoxidizing agent is allowed to act on the thus-synthesized polyether compound having a vinyl group side chain to synthesize the epoxy resin represented by the general formula (I). Examples thereof include peracids and hydroperoxides.

Examples of peracids include formic acid, peracetic acid, perbenzoic acid and trifluoroperacetic acid.

Of these, peracetic acid is industrially produced in large quantities,
It is a preferred epoxidizing agent because it is available at low cost and has high stability. Hydroperoxides include hydrogen peroxide, tertiary butyl hydroperoxide, cumene peroxide and the like. A catalyst may be used in the epoxidation, if necessary.

For example, in the case of peracid, an alkali such as sodium carbonate or an acid such as sulfuric acid can be used as a catalyst. In the case of hydroperoxides, a catalytic effect can be obtained by using a mixture of tungstic acid and caustic soda with hydrogen peroxide, an organic acid with hydrogen peroxide, or molybdenum hexacarbonyl with tert-butyl hydroperoxide. You can

The epoxidation reaction is carried out by adjusting the presence or absence of a solvent and the reaction temperature according to the physical properties of the equipment and raw materials. The reaction temperature range that can be used depends on the reactivity of the epoxidizing agent used. Peracetic acid, which is a preferred epoxidizing agent, is 0 to 70.
C is preferred.

The reaction is slow below 0 ° C, and the decomposition of peracetic acid occurs at 70 ° C.

In the tertiary butyl hydroperoxide / molybdenum dioxide diacetylacetonate system, which is an example of hydroperoxide, 20 ° C. to 150 ° C. is preferable for the same reason.

The solvent can be used for the purpose of reducing the viscosity of the raw material and stabilizing it by diluting the epoxidizing agent. In the case of peracetic acid, aromatic compounds, ethers such as peracids,
An alkali such as sodium carbonate or an acid such as sulfuric acid may be used as a catalyst.

The charged molar ratio of the epoxidizing agent to the unsaturated bond can be changed according to the purpose such as the amount of the unsaturated bond to be left.

When a compound having a large number of epoxy groups is intended, the epoxidizing agent is preferably added in an equimolar amount to the unsaturated group or more. However, it is usually disadvantageous that the amount exceeds 2 times the molar amount in view of economical efficiency and the side reaction described below, and 1 to 1.5 times the molar amount is preferable in the case of peracetic acid. Depending on the conditions of the epoxidation reaction, the epoxidation of the olefin group and the substituents in the raw material And comes to As a result of causing a side reaction with the epoxidizing agent, a modified substituent is generated and contained in the target compound.

further, And a mixture of modified substituents such as:

When the epoxidizing agent is peracetic acid, the modified substituent mainly has a structure as shown below and is generated from the generated epoxy group and by-product acetic acid.

In the epoxy resin represented by the general formula (I) which is the component (A) in the method for producing an unsaturated epoxy ester resin of the present invention, the substituent X is as follows. The larger the amount, the more preferable.

The method for producing an unsaturated epoxy ester resin of the present invention comprises an epoxy resin represented by the general formula (I), which is the component (A), and an unsaturated monocarboxylic acid, which is the component (B), synthesized as described above. Is heated in the presence of a reaction catalyst.

At this time, if necessary, the component (C) is a saturated monocarboxylic acid, a saturated polycarboxylic acid, a saturated polycarboxylic acid anhydride, an unsaturated polycarboxylic acid, an unsaturated polycarboxylic acid anhydride, or a terminal carboxyl group. It is possible to coexist one or more kinds selected from the unsaturated alkyds having the above and a polymerization inhibitor, a solvent or a polymerizable monomer which is the component (D). It is also possible to mix other epoxy resins.

As the other epoxy resin, any one that is generally used may be used, and examples thereof include epoxy diluents such as epibis type epoxy, bisphenol F type epoxy, alicyclic type epoxy, styrene oxide, and butyl glycidyl ether.

As the unsaturated monocarboxylic acid as the component (B), for example, acrylic acid, methacrylic acid, crotonic acid, etc. are generally used.

Specific examples of the component (C) used as necessary include acetic acid, benzoic acid, maleic anhydride, maleic acid, phthalic acid, phthalic anhydride, succinic acid, adipic acid,
Hexahydrophthalic anhydride, pyromellitic dianhydride, etc. may be mentioned, and one or more selected from them may be used.

The addition amount of the component (C), which is used as necessary, varies depending on the type of unsaturated monocarboxylic acid or carboxylic acid, but it is effective to add it in a weight ratio of 01.% or more. (C)
The purpose of adding the components is to modify the resulting unsaturated epoxy ester resin according to various uses.

The saturated or unsaturated alkyd having a terminal carboxyl group is an alkyd having a terminal carboxyl group obtained by the condensation reaction of a polyhydric alcohol and a polycarboxylic acid.

The reaction molar ratio of these carboxylic acid and epoxy resin is possible if the total of the carboxyl groups of the carboxylic acid is 0.1 mol or more per 1 mol of epoxy, but the preferable range from the viewpoint of curability and performance is 0.2 to 2 It is a mole.

Examples of the polymerization inhibitor include hydroquinone, methylhydroquinone, methoxyhydroquinone and the like.

Examples of the reaction catalyst used include tertiary amines such as triethylamine and benzylmethylamine, quaternary ammonium salts such as tetramethylammonium chloride, tetraemethylammonium chloride and tetramethylammonium bromide, diethylamine, acetate and formate. Secondary amine organic salts such as sodium hydroxide,
Alkali metals such as calcium hydroxide, hydroxides of alkaline earth metals, alkali metals such as sodium acetate, sodium formate, potassium acetate, alkaline earth metal salts, imidazoles, cyclic compounds such as diazabicycloundecene, etc. There are nitrogen compounds. The amount used is 0.01-5% with respect to the starting material.

Examples of the polymerizable monomer include methyl methacrylate, hydroxyethyl acrylate, styrene, vinyltoluene, ethylene glycol diacrylate, and trimethylolpropane triacrylate.

 The amount used is 10-80% with respect to the starting material.

Examples of the solvent include benzene, ethyl alcohol, ethyl acetate, toluene, ethyl cellosolve and the like, and one or more kinds can be used.

 The amount used is about 10 to 80% with respect to the starting material.

The epoxy resin and the carboxylic acid are heated and reacted in the presence of these, and the reaction temperature is 50 to 130 ° C, preferably 80 ° C.
Done at ~ 120 ° C.

[Effects of the Invention] The unsaturated epoxy ester resin obtained by the above-mentioned production method of the present invention gives a cured product having excellent heat resistance and weather resistance, and can be used in a very wide range.

 Next, the present invention will be described with reference to examples and comparative examples.

<< Example 1 >> 500 parts by weight of xylene was added to a flask equipped with a subordinate funnel, a stirrer, an air inlet tube, a thermometer, and a reflux condenser, and the general formula disclosed in JP-A-60-166675 was used. I)
Epoxy resin represented by [manufactured by Daicel Chemical Industries, Ltd.
EHPE-3150, epoxy equivalent 180] 300 parts by weight, hydroquinone 0.03 parts by weight, triethylbenzylammonium chloride 2.0 parts by weight were charged and stirred while gently blowing dry air and heated to 110 ° C.

Then, 100 parts by weight of acrylic acid was added dropwise from the dropping funnel over 1 hour. Then, the temperature was maintained at 110 ° C., and the reaction was continued by further stirring for 5 hours.

Then, it was cooled to 30 ° C, and the unsaturated epoxy ester resin solution [nonvolatile matter 45.5%, acid value 1.3KOHmg / g, epoxy equivalent
3160] was obtained.

Example 2 A flask similar to that of Example 1 was charged with 500 parts by weight of toluene and EHP.
E-3150 [epoxy equivalent 180] 300 parts by weight, hydroquinone 0.03 parts by weight, triethylbenzylammonium chloride 2.0 parts by weight were charged, and the mixture was stirred while gently blowing dry air and heated to 90 ° C. Then, 60 parts by weight of acrylic acid was dropped from the dropping funnel over 1 hour. afterwards,
The temperature was maintained at 90 ° C., and the reaction was continued by further stirring for 10 hours. Then, the mixture was cooled to 30 ° C. to obtain an unsaturated epoxy ester resin solution [nonvolatile matter 42.3%, acid value 0.3 KHOH mg / g, epoxy equivalent 310].

<< Comparative Example 1 >> 500 parts by weight of toluene, 300 parts by weight of bisphenol A type epoxy resin [Epicoat 828 made by Yuka Shell, epoxy equivalent 190], hydroquinone were added to the same flask as in Example 1.
0.03 parts by weight, triethylbenzylammonium chloride
1.0 part by weight was charged, and the mixture was stirred while slowly blowing dry air and heated to 90 ° C. Then, 100 parts by weight of acrylic acid was added dropwise from the dropping funnel over 1 hour. afterwards,
The temperature was maintained at 90 ° C., and the reaction was continued by stirring for 6 hours. Then, the mixture was cooled to 30 ° C. to obtain an unsaturated epoxy ester resin solution [nonvolatile matter 45.3%, acid value 1.7 KOHmg / g, epoxy equivalent 4600].

<Application Example> The composition shown in Table 1 was mixed, coated on a glass plate (coating thickness 100 μ), dried at 80 ° C. for 30 minutes, and then irradiated with an ultraviolet lamp to obtain a cured film. Curing conditions use MPM lamp, 80W
/ cm, the speed was 30 m / min. The properties of the obtained cured product are also shown in Table 1.

The following synthesis was carried out in order to investigate the content ratio of the kind of the substituent X in the epoxy resin represented by the general formula (I).

[Reference Synthesis Example 1] 161.0 g / h of peracetic acid (30% ethyl acetate solution), a polyether compound which is a precursor of the epoxy resin represented by the general formula (I) [trimethylol as an initiator having active hydrogen] Using propane (50% ethyl acetate solution)] [However, n1, n2, and n3 are 5 on average. A is represented by the following formula Was continuously charged to the reactor at a feed rate of 182.0 g / h.

The temperature was set to 50 ° C. While controlling the water washing tank at 50 ° C, water was charged at a supply rate of 340 g / h, and the separated upper tank was charged in the evaporation tank.

 The evaporation temperature was 120 ° C and the degree of vacuum was 70 mmHg.

The obtained epoxy resin is [However, n1, n2, and n3 are 5 on average. B has the structure of:

[Reference Synthesis Example 2] The same procedure as in Reference Synthesis Example 1 was performed except that the temperature was set to 40 ° C.

[Reference Synthesis Example 3] Reference Synthesis Example 1 was performed in the same manner as in Reference Synthesis Example 1 except that the temperature was set to 60 ° C.

[Reference Synthetic Example 4] Peracetic acid (30% ethyl acetate solution) was supplied at a rate of 322.0 g / h, and the same polyether compound (50% ethyl acetate solution) used in Reference Synthetic Example 1 was supplied at a rate of 364.0 g / h. Continuously,
Synthesis Example 1 except that the temperature of the reaction tanks was set to 50 ° C
I went the same way.

[Reference Synthesis Example 5] The same procedure as in Reference Synthesis Example 4 was carried out except that the temperature of the reaction vessel was set to 60 ° C.

Table 1 also shows various physical properties of the products obtained in Reference Synthesis Examples 1 to 5.

In addition, the analysis of oxirane oxygen in Table 1 was carried out by a direct titration method [a fixed amount of a sample was dissolved in chlorobenzene or benzene and titrated until a color change was obtained by adding a crystal violet indicator], and an iodine value was determined by the Wyeth method or saponification. Value is a chemical quantitative method [potassium hydroxide-ethanol solution is added to a fixed amount of a sample and titrated with hydrochloric acid using phenorphthalein as an indicator after heating] oxirane oxygen is an epoxy represented by general formula (I) Epoxy group in resin , The iodine value represents the content of vinyl group —CH═CH ₂ , and the saponification value represents the content of the ester group produced by hydrolysis of the epoxy group.

Claims (1)

(57) [Claims] 1. An epoxy resin represented by the following general formula (I): [However, in the general formula (I), R ¹ is a residue excluding active hydrogen in an organic compound having ¹ active hydrogen, n 1, n 2
... nl is 0 or an integer of 1 to 100, and the sum thereof is 1 to 100, l represents an integer of 1 to 100, B is an oxycyclohexane skeleton, and is represented by the following formula: However, X is However, R ² is H, an alkyl group, an alkylcarbonyl group,
An arylcarbonyl group, which is one of Containing at least one or more in the resin of formula (I)] and (B) unsaturated monocarboxylic acid and optionally (C) saturated monocarboxylic acid, saturated polycarboxylic acid, saturated polycarboxylic anhydride, Two components (A) and (B) consisting of one or more selected from unsaturated polycarboxylic acids, unsaturated polycarboxylic anhydrides, and unsaturated alkyds having a terminal carboxyl group, or ( It is characterized in that three components of A), (B) and (C) and optionally (D) a polymerization inhibitor, a solvent or a polymerizable monomer are heated and reacted in the presence of a reaction catalyst. Method for producing unsaturated epoxy ester resin.