JPH0735431B2 - Method for producing polyol resin - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for producing a polyol resin. More specifically, it relates to a method for producing a polyol resin by reacting a modified epoxy resin with a monocarboxylic acid.

[Conventional technology]

A so-called bisphenol type epoxy resin produced from bisphenol and epichlorohydrin or β-methylepichlorohydrin has been used for various purposes of curing by utilizing the reactivity of epoxy groups. On the other hand, a modified epoxy resin obtained by ring-opening an epoxy group with an active hydrogen compound utilizes the reactivity of the hydroxyl group in the resin to improve the adhesion and corrosion resistance of melamine, phenol, alkyd, urethane paints, etc. Used in.

In this case, the properties of the modified epoxy resin are greatly affected by the type of active hydrogen compound used for ring opening. For example, in the urethane coatings field, isocyanate, which is a curing agent, reacts with water contained in paint components such as vehicles, fillers, solvents, etc. and water in the air, resulting in foaming in the coating film, and this foam causes corrosion resistance, etc. Will adversely affect the coating performance of the.

In order to suppress such foaming, a high-molecular-weight resin is used as a raw material resin, or an active hydrogen compound having a primary hydroxyl group which is highly reactive with an isocyanate group is used as a modifier to make it reactive in the resin. It is known that a hydroxyl group having a high However, the resin thus modified has a drawback that its compatibility with an aromatic compound such as toluene and xylene, which is usually used as a solvent for coating materials, becomes extremely low.

[Problems to be solved by the invention]

Therefore, the inventors of the present invention have made various investigations for a modified epoxy resin having low foaming and excellent compatibility with an aromatic hydrocarbon solvent, and as a result, have found that the reaction product of a bisphenol type epoxy resin and an active hydrogen-containing compound is a substance. It has been found that the above problems can be solved by esterifying a part of hydroxyl groups in a modified epoxy resin having no epoxy group with a monocarboxylic acid to form a polyol resin.

[Means for Solving Problems] and [Action] Therefore, the present invention relates to a method for producing a polyol resin, which is produced by (a) a bisphenol epoxy resin represented by the following general formula: R ′: hydrogen atom or halogen atom R ″: hydrogen atom or methyl group n: the number of repeating units, which may be 0, and (b) has substantially no epoxy group as a reaction product of the active hydrogen-containing compound. It is carried out by reacting a modified epoxy resin with a monocarboxylic acid.

The bisphenol type epoxy resin of the component (a) represented by the above general formula is a reaction of phenol or 2,6-dihalobisphenol with aldehydes or ketones such as formaldehyde, acetaldehyde, acetone, acetophenone, cyclohexanone, benzophenone, and Can be obtained by condensation reaction of bisphenols obtained by oxidation of dihydroxyphenyl sulfide with peracid, etherification of hydroquinone, and epichlorohydrin or β-methylepichlorohydrin.

Examples of the active hydrogen-containing compound as the component (b) used as a modifier for these bisphenol type epoxy resins include:
For example, diethanolamine, diisopropanolamine, bis (2-hydroxybutyl) amine, bis (2-
Alkanolamines having 2 to 20 carbon atoms such as hydroxyoctyl) amine, N-methylethanolamine, N-methylisopropanolamine, N-ethylethanolamine and N-benzylethanolamine, phenol,
C6-C30 phenols such as cresol, isopropylphenol, isobutylphenol, nonylphenol, xylenol, di-s-butylphenol, and di-tert-butylphenol, especially alkylphenols, and further diethylamine, dibutylamine, N-methylaniline and the like. Secondary amines having 4 to 20 carbon atoms, acetic acid, stearic acid, undecylenic acid, benzoic acid, monocarboxylic acids having 2 to 30 carbon atoms such as toluic acid, methanol, propanol, butanol, octanol, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6
-Alcohols having 1 to 30 carbon atoms such as hexanediol and diethylene glycol are used.

The component (a) and the component (b) are used in a ratio such that the component (b) is 0.95 to 1.05, preferably 0.98 to 1.00 with respect to the epoxy group in the component (a). Further, if desired, bisphenols and / or primary amines may be allowed to coexist during the reaction, and the reaction may be carried out while extending the chain length.

This reaction is generally carried out in the presence of a catalyst and a solvent at a temperature of about 50-250 ° C, preferably about 100-200 ° C. If the reaction temperature is lower than this, the reaction rate becomes slower, while if the reaction temperature is higher than this, the reaction between the epoxy group and the hydroxyl group or the ring opening reaction between the epoxy groups occurs at the stage of forming the epoxy resin modified product. , There is a risk of gelation of the reaction product.

Examples of the catalyst include alkali metal hydroxides such as sodium hydroxide and lithium hydroxide, alkali metal alcoholates such as sodium methylate, tertiary amines such as dimethylbenzylamine, triethylamine and pyridine,
Quaternary ammonium salts such as tetramethylammonium chloride and benzyltrimethylammonium chloride, organic phosphorus compounds such as triphenylphosphine and triethylphosphine, quaternary phosphonium salts such as triphenylphosphine / methyl iodide adducts, sodium carbonate, lithium chloride, etc. Alkali metal salts of the above, boron trifluoride, aluminum trichloride, Lewis acids such as tin tetrachloride, and complexes such as boron trifluoride / diethyl ether adduct, etc. are generally about 0.01-10000 ppm with respect to the component (a), Preferably about 0.1 to 1000 ppm is used. Further, the alkanolamines in the component (b) are used as a catalyst per se. In this case, it is also possible to first use a catalytic amount of alkanolamines to react with another active hydrogen-containing compound, and then add the remaining alkanolamine to the reaction to react.

When a solvent is used, hydrocarbons such as toluene and xylene, ketones such as methyl isobutyl ketone, methyl ethyl ketone, and cyclohexanone that do not have active hydrogen are used.

The epoxy resin modified product obtained as a result of such a reaction is
Then about 2 to 98% by weight of monocarboxylic acid with each other
React at a rate of. Examples of the monocarboxylic acid used include carbonic acid having 3 carbon atoms such as propionic acid, caprylic acid, lauric acid, palmitic acid, stearic acid, castor oil fatty acid, undecylenic acid, dehydrated castor oil fatty acid, linoleic acid, linolenic acid and tall oil fatty acid. -30 saturated or unsaturated monocarboxylic acids are mentioned.

The reaction is carried out in the presence or absence of catalyst and solvent at about 150-300 ° C, preferably about 180-250 ° C. If the reaction temperature is lower than this, the reaction rate becomes slow, while the reaction temperature higher than this may cause deterioration of the resin.

The catalyst, tetrabutyl titanate, tetraethyl titanate, butoxy titanium trichloride, organic or inorganic titanium compounds such as titanium tetrachloride, triethyl aluminum, ethyl aluminum chloride, organic or inorganic aluminum compounds such as aluminum trichloride,
Organic or inorganic zinc compounds such as diethylzinc and zinc chloride, dibutyltin laurate, organic or inorganic tin compounds such as stannous chloride, boron trifluoride, p-toluenesulfonic acid, acids such as phosphoric acid, lithium, sodium,
Alkali metal or its complex such as sodium naphthalene and potassium benzophenone, alkali metal hydroxide such as lithium hydroxide and sodium hydroxide, alkali metal salt such as sodium carbonate and lithium acetate, alkali metal hydride such as lithium hydride and sodium hydride , Triethylamine, tertiary amines such as pyridine, etc. are generally about 0.01 to 1000 relative to the modified epoxy resin obtained by reacting the components (a), (b) and (c).
ppm, preferably about 0.1 to 500 ppm.

As the solvent, the same solvent as that used for the production of the modified epoxy resin is used.

The polyol resin thus obtained is a baking coating by combination with a resin having a methylol group such as melamine resin, urea resin or other amino resin, or resole, and is dried at room temperature by combination with isocyanate, blocked isocyanate or the like. It can be used as a paint or a baking paint.

Further, other polyol resins such as polyester polyol and acrylic polyol, polyethers such as polyethylene glycol and polypropylene glycol, polyester resin, acrylic resin, fibrin resin and the like may be blended and used as a modifier for these. .

When used in various applications, if desired, talc, calcium carbonate, silica, carbon, white tars including petroleum resins, various vinyl compound polymers, tars, inorganic or organic fillers such as asphalt, and pigments. It is also possible to mix such as there.

〔The invention's effect〕

The polyol resin produced by the present invention has the following effects.

(1) By using an active hydrogen-containing compound as a ring-opening agent for an epoxy group in the production of a modified epoxy resin as a raw material for a polyol resin, compatibility with an aromatic compound solvent and foaming prevention in the case of isocyanate curing , Coating film formability and the like are improved.

(2) Petroleum resin, which has poor compatibility with conventional polyol resins made from epoxy resins, oligomers of styrene compounds such as styrene and α-methylstyrene, and oligomers based on hydrocarbon monomers such as xylene resins. The compatibility with organic fillers for paints such as ketone resins and coumarone resins, so-called white tar, is also improved.

(3) When the polyol resin according to the present invention is applied to coating, corrosion resistance, chemical resistance, adhesion to a substrate,
A film having excellent wear resistance and flexibility is formed.

(4) Even if a relatively low molecular weight epoxy resin is used as a raw material,
Since it is possible to reduce foaming when used in urethane paints, it is possible to reduce the viscosity of solvent-based paints and to make them highly solid.

〔Example〕

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

Example 1 Production of Polyol Resin A bisphenol A type epoxy resin (Mitsui Petrochemicals R-30 was placed in a separable flask having a capacity of 2 liters, equipped with a stirrer, a thermometer, and a cooling tube with a receiver for storing a condensate.
4. Epoxy equivalent 925) 925 g was charged, the system was replaced with nitrogen, xylene 50 g was added, and the temperature was raised to 120 ° C. with stirring in an oil bath. Next, 105 g of diethanolamine was gradually dropped from the dropping funnel to raise the temperature to 150 ° C., and the reaction was continued at this temperature until the epoxy equivalent of the reaction product reached 20,000 or more.

After that, 288 g of stearic acid was added, and while raising the temperature of the system to 250 ° C., an esterification reaction was carried out until the acid value became 1 or less, and the water produced at that time was azeotropically distilled with xylene,
Only water was removed outside the reaction system. After completion of the reaction, a mixed solvent of methyl isobutyl ketone-toluene and the like was used for dilution so that the nonvolatile content in the solution was about 60 wt%.

The obtained polyol resin solution has a nonvolatile content of 60.2% by weight,
Viscosity 2100 cps (B type viscometer, 25 ° C), toluene tolerance (addition weight of triene until reaching cloud point when toluene is added to 100 g of resin solution at 25 ° C) 141 g,
The hydroxyl value of the polyol resin itself was 191 mg-KOH / g.

Paint evaluation 100 parts (weight, same below) of the above polyol resin solution, 109 parts of bituminous material (Yoshida Oil Product Turklon 230), talc (Asada Flour Imported Talc) 91 parts, xylene-cyclohexanone (9: 1) mixed solvent 36 parts And a thixotropic agent (Nippon Aerosil product Aerosil # 300) 13 parts of the main agent and an isocyanate curing agent (Takenate D-102, Takeda Pharmaceutical Co., Ltd.) are mixed so that the NCO / OH molar ratio becomes 0.8, A tar urethane paint was prepared, and the paint was evaluated for the following items.

(Pot life) Using a B-type viscometer at 25 ° C, measure the time for the viscosity of the mixed paint to double the initial viscosity. (Drying property) After applying the mixed paint to a 0.3 mm thick polished mild steel plate, Gardner Using a dry time measuring instrument (Kamishima Seisakusho), 20 ℃
Measured as the half-curing time when the needle no longer penetrates into the wet coating with a film thickness of 500μ (pencil hardness) Measured according to JIS K-5400 at 20 ° C according to JIS K-5400 (foaming state) ) Cure the compounded paint at 20 ° C in a polyethylene cup,
It was cut in a thickness direction of about 4 cm and the foaming state in the cured product was observed. Examples 2-3 In Example 1, the amount of stearic acid used was variously changed.

Examples 4-9 In Example 1, instead of stearic acid, the specified amounts of other monocarboxylic acids were used.

The same evaluations as in Example 1 were carried out on the polyol resin solutions obtained in the above examples and the tar urethane coatings prepared therefrom. The evaluation results obtained are shown in Table 1 below.

Example 10 In Example 1, 940 g of another bisphenol A type epoxy resin (Mitsui Petrochemical R-301, epoxy equivalent 470) was used, and the amount of diethanolamine used was 210 g,
The amount of stearic acid used was changed to 414 g.

Example 11 In Example 1, 900 g of another bisphenol A type epoxy resin (epoxy equivalent of 1800) was used, the amount of diethanolamine used was 52 g, and the amount of stearic acid used was 2 g.
Changed to 24g respectively.

Example 12 In Example 1, another bisphenol A type epoxy resin (epoxy equivalent: 3000) was used in an amount of 1000 g, isopropylphenol was used in place of diethanolamine in an amount of 45 g, and the amount of stearic acid used was changed to 187 g.

Example 13 In Example 1, 600 g of another bisphenol A type epoxy resin (epoxy equivalent 189) was used together with 264 g of bisphenol A as a chain extender, the amount of diethanolamine used was 91 g, and the amount of stearic acid used was 267 g. Respectively changed to.

Examples 14-1 to 14-9 In Example 13, other bisphenol type epoxy resins and / or bisphenols were used in place of the bisphenol A type epoxy resin and / or bisphenol A.

The same evaluations as in Example 1 were performed on the polyol resin solutions obtained in Examples 10 to 13 and Examples 14-1 to 14-9 and the tar urethane coatings prepared therefrom. The obtained evaluation results are shown in Table 2-1 and Table 2-2 below.
Shown in.

Example 15 In Example 13, the amount of stearic acid used was changed to 380 g, the nonvolatile content was 59.2% by weight, the viscosity was 2300 cps (25 ° C.), the toluene tolerance was 380 g, and the hydroxyl value of the polyol resin itself was 15
A 4 mg-KOH / g polyol resin solution was prepared.

100 parts of this polyol resin (weight, the same below), 88 parts of xylene resin (Mitsubishi Gas Chemicals Nikanol L), 114 parts of talc (Asada Flour Imported Talc), 18 parts of titanium white (Ishihara Sangyo Product Taipaque R-820), xylene -A base compound consisting of 29 parts of cyclohexanone (9: 1) mixed solvent and 15 parts of thixotropic agent (Aerosil # 300 of Nippon Aerosil Products) and an isocyanate curing agent (Takenate D-10 of Takeda Pharmaceutical Co., Ltd.)
2) and were mixed so that the NCO / OH molar ratio would be 0.8 to prepare a white tar urethane coating.

The white tar urethane coating thus prepared was evaluated in the same manner as in Example 1.

Examples 16-21 In Example 15, instead of stearic acid, certain amounts of other monocarboxylic acids were used.

The polyol resin solutions obtained in the above Examples 15 to 21 and the white tar urethane coatings prepared therefrom were evaluated in the same manner as in Example 1. The evaluation results obtained are shown in Table 3 below.

Example 22 The amount of diethanolamine used in Example 15 was 46 g.
The amount of stearic acid used was changed to 212 g, and 60 g of isopropylphenol was used as an active hydrogen-containing compound.

Example 23 In Example 15, 306 g of stearylamine was used instead of bisphenol A, the amount of diethanolamine was changed to 95 g, and the amount of stearic acid was changed to 259 g.

Example 24 In Example 15, 134 g of resorcin was used instead of bisphenol A, and the amount of diethanolamine used was 77 g.
The amount of stearic acid used was changed to 360 g.

The same evaluations as in Example 1 were performed on the polyol resin solutions obtained in Examples 22 to 24 and the white tar urethane coatings prepared therefrom. The obtained evaluation results are shown in Table 4 below.

Comparative Example 1 In Example 1, esterification with stearic acid was not performed. The obtained polyol resin was diluted with a mixed solvent of methyl isobutyl ketone-toluene and the like to a nonvolatile content of about 60% by weight, but it was not completely dissolved and a non-uniform dispersion liquid was formed. The hydroxyl value of the resin itself was 308 mg-KOH / g.

Comparative Example 2 In Example 22, esterification with stearic acid was not performed. The obtained polyol resin solution has a nonvolatile content.
It was 60.9% by weight, viscosity was 8900 cps (25 ° C.), toluene tolerance was 14 g, and the hydroxyl value of the resin itself was 240 mg-KOH / g.

An attempt was made to prepare a white tar urethane paint using this polyol resin solution, but the polyol resin and the xylene resin caused phase separation, and the paint could not be prepared.

Claims (2)

[Claims] 1. A bisphenol type epoxy resin represented by the following general formula: R ′: hydrogen atom or halogen atom R ″: hydrogen atom or methyl group n: the number of repeating units, which may be 0, and (b) has substantially no epoxy group as a reaction product of the active hydrogen-containing compound. A method for producing a polyol resin, which comprises reacting a modified epoxy resin with a monocarboxylic acid. 2. The method for producing a polyol resin according to claim 1, wherein the modified epoxy resin and the monocarboxylic acid are reacted in a proportion of about 2 to 98% by weight, respectively.