JPS6223738B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a vinyl ester resin, and particularly to a method for producing a vinyl ester resin from an α-glycol resin having an α-glycol terminal group and an unsaturated monobasic acid. In recent years, unsaturated epoxy ester resins, which are made by dissolving a reaction product of an epoxy compound and an unsaturated monobasic acid in a polymerizable monomer such as styrene, have improved the performance of epoxy resins and the workability and curing properties of unsaturated polyester resins. It is beginning to attract attention as a product that combines the following. The fields of application of such unsaturated epoxy ester resins, like unsaturated polyester resins, are corrosion-resistant reinforced plastics, filament winding,
It is used in a wide range of applications including lining, adhesive molding, and casting molding, but its use as highly corrosion-resistant reinforced plastics is attracting the most attention. In addition, the type of epoxy compound that is the ester component of this unsaturated epoxy ester resin,
By selecting materials with different degrees of polymerization or by blending them with each other, a wide variety of performances can be provided. The above unsaturated epoxy ester resin is produced by a reaction in which an epoxy group in an epoxy compound is ring-opened with a carboxyl group in an unsaturated monobasic acid such as acrylic acid, methacrylic acid, etc., and esterified to produce an epoxy ester. Various methods have been studied to facilitate this reaction (Japanese Patent Publication No. 31472-1972, Publication No. 21520-1977). However, the esterification reaction of an epoxy compound with an unsaturated monobasic acid, which involves a ring-opening reaction, is a very violent reaction, and the heat generated at that time causes radical polymerization to proceed in a chain manner, and there is an extreme risk of gelation. high and a solution is desperately needed. As a method of preventing gelation due to polymerization when reacting such polymerizable compounds, it has been proposed to use phenols and quinones such as hydroquinone, and to conduct such reactions in the presence of air. However, when heating is continued for a long time in order to lower the acid value to 2 to 15, which is the same level as in conventional esterification reactions, it has been impossible to completely prevent such gelation. As a result of intensive research, the inventors of the present invention found that, in place of the epoxy compound conventionally used in the production of unsaturated epoxy esters,
54-3900), the compound represented by the following formula is described as an α-glycol resin. In the formula, A is -CH ₂ -,

[Formula] or _-SO2- group; R is a hydrogen atom or a methyl group; _X1 , _X2 , _X3 , _X4 , _X5 , _X6 , _X7 and _X8 are the same or different; may be a hydrogen atom, a chlorine atom or a bromine atom, respectively; T ₁ and T ₂ represent terminal groups, which may be the same or different, and substantially represent the following groups:

[Formula] Hydrogen atom,

[Formula] and

[Formula] [In the formula, the definition of R is the same as above, and either Y ₁ or Y ₂ represents a hydroxyl group, and the other represents a chlorine atom or a bromine atom] ; n represents the average degree of polymerization, is greater than 0 and 29
It consists of an α _- glycol resin represented _by And the remaining 60-2% are the following group hydrogen atoms,

[Formula] and

[Formula] is an atom or atomic group chosen _from α-glycol terminal group-containing compounds including α-glycol resins exhibiting a value of
The inventors have discovered that gelation due to polymerization of such a polymerizable compound can be prevented by causing a dehydration condensation reaction with an unsaturated monobasic acid, and the esterification reaction can be carried out safely, and in order to complete the present invention. I've reached it. That is, the present invention provides the general formula In the formula, A is -CH ₂ -,

[Formula] or -SO ₂ - group; R is a hydrogen atom or a methyl group; R ₁ and R ₂ may be the same or different and are each a hydrogen atom or an alkyl group; X ₁ , X ₂ , X ₃ , X ₄ , X ₅ , X ₆ , X ₇ and X ₈ may be the same or different and are each _a hydrogen atom or _a halogen atom; but may also be different, including substantially the following groups: (1)

【formula】 (2) Hydrogen atom (-H), (3)

[Formula] and (Four)

[Formula] However, in the above formulas (1) to (4), the definition of R is the same as above, and either Y ₁ or Y ₂ represents a hydroxyl group, and the other represents a chlorine atom or a bromine atom. selected atoms or atomic groups; n represents the average degree of polymerization and is 0 or a positive number greater than 0; at least 40 of all terminal groups (sum of T ₁ and T ₂ ); % is the α-glycol group below. This is a method for producing a vinyl ester resin, which is characterized by reacting an α-glycol resin with a polymerizable unsaturated monobasic acid. The reason why gelation due to polymerization of the polymerizable compound is prevented during the reaction by the method of the present invention is probably because the heat generation accompanying the esterification reaction is alleviated by the latent heat of vaporization of water generated by the dehydration condensation reaction. , as a result, gelation during the reaction is thought to be prevented. The reaction between the α-glycol resin and the unsaturated monobasic acid can generally be carried out by a method generally known as an esterification reaction method, similar to the case of producing an epoxy ester. That is, for 1 mole of α-glycol resin,
The carboxyl group in the unsaturated monobasic acid is approximately 0.2 to 2.2
α-Glycol resin and unsaturated monobasic acid are mixed in an amount such that the mole ratio is preferably 0.8 to 1.2 moles, and the mixture is mixed with an unsaturated monobasic acid in an amount of about 80 to 180 moles in the presence of a known esterification catalyst.
This can be suitably carried out by reacting at a temperature of 100 to 150°C, preferably 100 to 150°C, until the acid value of the resulting resin reaches 15 to 2. In such a reaction, in order to make the reaction proceed smoothly, it is desirable to bubble oxygen or air into the system, and to remove the water produced by the condensation reaction from the system along with the bubbles. Generally the reaction time is 3 to 15 hours, preferably 5 to 8 hours.
It's time. This reaction can be carried out without using a reaction solvent, but one may also be used. When using an α-glycol resin with a high degree of polymerization (n > 3 in the general formula), an ethylenically unsaturated group-containing monomer that can be copolymerized with the vinyl ester resin to be produced is subjected to an esterification reaction. thing
It is preferable to allow the reaction to proceed in a low viscosity state by adding 1 part or more, preferably 10 to 30 parts, per 100 parts. This copolymerizable monomer becomes a component of the cured resin when the vinyl ester resin is cured later, so there is no need to remove it after the reaction is completed. Examples of such monomers that can be used are the same as the examples of ethylenically unsaturated group-containing monomers used to dissolve the vinyl ester product after the reaction is completed to form a liquid resin, which will be described later. However, the monomers added during the reaction need not be of the same type as the monomers added after the reaction is complete. In place of the ethylenically unsaturated monomer, a non-reactive solvent such as toluene, benzene or chloroform can be used to lower the viscosity. However, the use of a solvent such as toluene is economically disadvantageous because it becomes necessary to remove the solvent from the esterification product after the reaction. Further, the reaction in the method of the present invention is preferably carried out in the presence of a known polymerization inhibitor, and such compounds include, for example, hydroquinone, ditertiarybutylhydroxytoluene, hydroquinone monomethyl ether, tertiarybutylcatechol, benzoquinone, etc. Examples include mono- or polyhydric phenols and quinones. The amount used is about 0.001-1.0% by weight based on the reaction mixture, preferably 0.005%.
~0.5% by weight. Among the α-glycol resins of the general formula () used in the present invention, examples of resins with an average degree of polymerization n greater than 0 and their manufacturing method are disclosed in Japanese Patent Application No. 52-68926 (Japanese Patent Application Laid-Open No. 54-3900). ) are explained in detail in the specification. The α-glycol resin obtained by this method is
α-Glycol group as a molecular terminal group

[Formula] (where R is a hydrogen atom or a methyl group) at least 40% by weight of all end groups, preferably
It contains 60% by weight or more, more preferably 90% by weight or more. Further, in the present invention, an α-glycol resin in which R in the formula of the α-glycol group is a hydrogen atom is usually used. In addition, in the general formula (), a preferable example of a compound where n is 0 is the following general formula (') (In the formula, R ₁ , R ₂ , X ₅ , X ₆ , X ₇ and X ₈ have the same meanings as above.) (In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or an alkyl group, and X ₅ , X ₆ , X ₇ and X ₈ each independently represent a hydrogen atom or a halogen atom) In the compound, the following formula ()

[Formula] and/or

It can be produced by reacting a glycerin monohalohydrin compound represented by the formula: (wherein X represents a halogen atom) in the presence of an alkali catalyst. Preferred examples of the compound of formula () used in the production of the compound of formula (') above are 4,4'-dihydroxydiphenyl-2,2-propane, 4,4'-
Dihydroxydiphenylmethane, 4,4'-dihydroxydiphenyl-2,2-butane, 4,4-dihydroxydiphenyl-3,3-pentane, 4,
4'-dihydroxy-3,3',5,5'-tetrabromo-2,2-propane, 4,4'-dihydroxy-
3,3',5,5'-tetrabromomethane, 4,4'-
Dihydroxy-3,3',5,5'-tetrachloro-
2,2-propane and 4,4'-dihydroxy-
3,3',5,5'-tetrachloromethane, etc. Further, in a preferable compound of the formula (), X is a chlorine atom, that is, glycerin-α-monochlorohydrin, glycerin-β-monochlorohydrin, or a mixture thereof. The compound of the formula (') is prepared by combining the bisphenols of the formula () and the glycerin monohalohydrins of the formula () in the presence of an alkali catalyst for 50 to 200%
℃, preferably 60-200℃, more preferably 80-120℃
It can be conveniently prepared by reacting at a temperature in the range of .degree. C. for 10 minutes to 5 hours, preferably 20 minutes to 5 hours. The ratio of the bisphenols and the glycerin monohalohydrin compound to be used is preferably 1 equivalent or more, preferably 1.0 to 1.5 equivalents, based on the phenolic hydroxyl group of the bisphenols. Catalysts that can be used include hydroxides of Group A or Group A metals, such as caustic alkalis such as sodium hydroxide or potassium hydroxide, and calcium hydroxide, or substances whose aqueous solutions are alkaline, such as those mentioned above or other than those mentioned above. Examples include metal carbonates, secondary phosphates, orthophosphates, and silicates. Among these, metal hydroxides are preferred, and the amount used is less than that of glimoline monohalohydride. A suitable amount is 1 equivalent or more, preferably 1.00 to 1.50 equivalents, based on the phosphorus compound. The method for producing the compound of formula (') described above is described in the patent application filed by the present applicant on February 8, 1978.
Patent application specification for the title of the invention, "Novel hydroxyalkylation method of bisphenols"
54-106456). For example, the general formula (In the formula, R ₁ and R ₂ each independently represent a hydrogen atom or an alkyl group, and X ₁ , X ₂ , X ₃ and X ₄ each independently represent a hydrogen atom or a halogen atom) The compound has the formula

[Formula] and/or

It can be obtained by reacting a glycerin monohalohydrin compound represented by the formula: (wherein X represents a halogen atom) in the presence of an alkali catalyst. In the present invention, the above formula () or (′)
Examples of unsaturated monobasic acids that can be reacted with the α-glycol resin represented by the formula include acrylic acid, methacrylic acid, and crotonic acid. Further, a portion of the unsaturated monobasic acid used in the present invention may be replaced with, for example, a saturated monobasic acid, a saturated dibasic acid, or an unsaturated dibasic acid. These acids contain 80% of the total acid component used.
It may be used in amounts up to % by weight, preferably from 10 to 60% by weight. Examples of acids that can be used in place of some of the unsaturated monobasic acids are acetic acid, propionic acid, benzoic acid, phthalic acid, isophthalic acid, terephthalic acid,
These include tetrahydrophthalic anhydride, succinic acid, adipic acid, maleic acid, fumaric acid, and maleic anhydride. As the esterification catalyst used in the present invention,
Known ones can be conveniently used, for example (1)N,
Tertiary amines such as N-dimethylaniline, pyridine, triethylamine, hexamethylene diamine and their inorganic acids such as hydrochloric acid salts or organic acids such as acetic acid salts (2) Quaternary ammoniums such as tetramethylammonium chloride and trimethyldodecylbenzylammonium chloride Salts (3) Sulfonic acids and sulfonium salts such as para-toluenesulfonic acid and triphenylsulfonium chloride; (4) Mercaptans such as ethyl mercaptan and propyl mercaptan; (5) Sulfides such as dimethyl sulfide and methyl phenyl sulfide; (6) Sulfoxides such as dimethyl sulfoxide and methyl ethyl sulfoxide; (7) sulfonium salts such as trimethylsulfonium chloride and dimethylphenylsulfonium chloride; (8) phosphonium salts such as phosphonium iodide; (9) lithium chloride and bromide. Metal halides such as lithium, stannous chloride, zinc chloride, (10) metal hydroxides such as potassium hydroxide, lithium hydroxide, (11) alkali metal salts of organic acids such as sodium benzoate, potassium acetate, etc. can be mentioned. The amount of these esterification catalysts used may be the amount normally used, about 0.005% based on the reaction mixture.
~1% by weight. The vinyl ester resin thus obtained can be cured alone or with a suitable curing agent, but usually 30 to 80 parts by weight of the esterified resin, preferably 40 to 70 parts by weight, is added to a vinyl ester such as styrene. 70 to 20 parts by weight of an ethylenically unsaturated group-containing monomer copolymerizable with the resin, preferably 60 to 20 parts by weight
It is dissolved in 30 parts by weight and used as a liquid resin. This liquid resin is similar to unsaturated polyester resin,
For example, it is possible to cure at room temperature with a combination of methyl ethyl ketone peroxide monocobalt salt, and it is also possible to cure at high temperature by adding a high temperature catalyst such as benzoyl peroxide. Examples of the copolymerizable ethylenically unsaturated group-containing monomer used above include styrene, acrylate, methacrylate, vinyltoluene, chlorostyrene, vinylbenzene, acrylonitrile, methacrylonitrile, cyclopentadiene,
Divinylbenzene, vinylpyridine, vinyl acetate, diallyl phthalate, glycidyl methacrylate and the like can be used, and when the reaction is carried out, one or more of them can be used in combination. The present invention will be further explained below with reference to Examples.
In the examples, parts and percentages are by weight unless otherwise specified. Among the physical property values described in the Examples, the method for measuring the α-glycol group content is as follows. Measurement of α-glycol group content Accurately weigh the sample into a 300 ml Erlenmeyer flask, add 25 ml of chloroform and dissolve. After immersing this in a 0°C water bath for 30 minutes, 25 ml of benzyltrimethylperiodide ammonium solution was added, and the mixture was further kept in a 0°C water bath for 2.5 hours. Then, 5 ml of 10% sulfuric acid solution and 20% potassium iodide solution.
After adding 15 ml, titrate with 0.1N sodium thiosulfate standard solution. Alternatively, the same operation was performed without adding a sample as a blank, and the amount was quantified according to the formula below. α-Glycol group content (equivalent value/1000gr) = (BS) x N x F/200 x W B: Amount of sodium thiosulfate standard solution consumed for blank S: Sodium thiosulfate standard solution consumed for sample measurement Amount N: Normality of sodium thiosulfate standard solution F: Factor W of sodium thiosulfate standard solution: Weight of collected sample Example 1 (A) Production of α-glycol resin 100 parts of propane, 20 parts of epichlorohydrin, 97 parts of glycerin monochlorohydrin, and 230 parts of water were placed in a 10 stainless steel reaction vessel and mixed with stirring. The resulting mixture was heated to 100° C., and 40 parts of a 25% NaOH aqueous solution was added to the mixture over 15 minutes while maintaining the same temperature, and stirring was continued at the same temperature for an additional 35 minutes. Next, 330 parts of methyl isobutyl ketone was added to the reaction mixture, stirred thoroughly, and dissolved at 120°C. After the resulting mixture was allowed to stand still, the lower aqueous layer was separated and removed.
The upper methyl isobutyl ketone layer was further washed twice with warm water, and then the methyl isobutyl ketone was distilled off to obtain 139 parts of resin. The properties of the obtained resin were as follows. Viscosity (40% butyl carbitol solution) F ^- (Gardner-Holt method) Softening point 67℃ (Duran method) Terminal group content α-glycol group 3.4 (Equivalent value/1000g) Phenolic hydroxyl group 0.069 (Equivalent value/1000g) Epoxy group 0.004 (Equivalent value/1000g) Saponifiable chlorine 0.008 (Equivalent value/1000g) (B) Production of vinyl ester resin 1000 parts of α-glycol resin obtained in (A) above, 320 parts of methacrylic acid, 0.66 parts of hydroquinone, Heat 8.0 parts of para-toluenesulfonic acid in a flask to approx.
After the α-glycol resin was melted at 70°C, the reaction was proceeded with stirring while bubbling air. temperature
If the reaction continues for 3 hours after reaching 130℃, the acid value will be
I turned 33. The reaction continued for another 3 hours and the acid value was 8.
It became. During this time, 51 c.c. of reaction product water was discharged from the system. The vinyl ester resin obtained had an α-glycol group content of 0.05 equivalent/1000 g, a viscosity of 3 poise, and a reaction rate of 98.5%. This decrease in acid value and α-glycol group content indicates that the α-glycol group, which is the terminal group, of the α-glycol resin reacted with methacrylic acid to form a vinyl ester. Furthermore, when 550 parts of styrene was added to this resin, a pale yellow transparent liquid vinyl ester resin composition was obtained. To 100 parts of this vinyl ester resin composition, 2.0 parts of methyl ethyl ketone peroxide and 0.5 parts of cobalt naphthenate (containing 6% Co) were added.
It gelatinized in 16 minutes at room temperature and hardened in 22 minutes. Comparative Example A reaction was started in a flask with 636 parts of Epicote 828 (epoxy equivalent: 187, a product of Ciel Chemical Co., Ltd.), 292 parts of methacrylic acid, 0.5 parts of hydroquinone, and 6.0 parts of para-toluenesulfonic acid in an air atmosphere at 120°C. During the reaction, the temperature suddenly rose, making it difficult to control the temperature and causing gelation. Example 2 (A) Production of α-glycol resin 100 parts of 2,2-bis(4-hydroxyphenyl)propane, 71 parts of epichlorohydrin, 160 parts of water, and 0.05 part of tetramethylammonium bromide.
The resulting mixture was stirred and mixed in a 10 stainless steel reaction vessel, and the resulting mixture was heated to 115°C with stirring, and reacted at the same temperature for 30 minutes. The reaction mixture was then cooled to 100°C, and 15% of 136 parts of a 25% NaOH aqueous solution was added.
The mixture was added over a period of minutes and stirred at 100°C for an additional 35 minutes. Further add methyl isobutyl ketone to the reaction mixture.
330 parts were added and thoroughly stirred to dissolve the resin at 120°C. After the resulting mixture was allowed to stand still, the lower aqueous layer was separated and removed. The upper methyl isobutyl ketone layer was further washed twice with warm water, and then the methyl isobutyl ketone was distilled off to obtain 130 parts of a pale yellow resin. The properties of the obtained resin were as follows. Viscosity (40% butyl carbitol solution) Q (Gardner-Holdt method) Softening point 105℃ (Duran method) Terminal group content α-Glycol group 1.6 (Equivalent value/1000g) Phenolic hydroxyl group 0.030 (Equivalent value/1000g) Epoxy group 0.018 (Equivalent value/1000g) Saponifiable chlorine 0.013 (Equivalent value/1000g) (B) Production of vinyl ester resin 1000 parts of α-glycol resin obtained in (A) above, 200 parts of styrene, 8.0 parts of para-toluenesulfonic acid, When 0.7 parts of hydroquinone and 148 parts of methacrylic acid were reacted in a flask in the same manner as in Example 1, the acid value reached 7 after 10 hours. During this time, 20 c.c. of reaction product water was discharged out of the system. The vinyl ester resin obtained had an α-glycol group content of 0.04 equivalent/1000g, a viscosity of 5 poise, and a reaction rate of 97.5%. A mixture of 100 parts of a vinyl ester resin composition obtained by adding 600 parts of styrene to this resin, 2.0 parts of methyl ethyl ketone peroxide, and 0.5 parts of cobalt naphthenate (containing 6% Co) was prepared in 30 minutes at room temperature. It gelatinized and hardened in 52 minutes.

Claims (1)

[Claims] 1. General formula In the formula, A is -CH ₂ -, [Formula] or -SO ₂ - group; R is a hydrogen atom or a methyl group; R ₁ and R ₂ may be the same or different, and each is a hydrogen atom or an alkyl group. _{and _ _ _ _ _ _ _ _ _} Represents a terminal group, which may be the same or different, and substantially includes the following groups: (1) [Formula] (2) Hydrogen atom (-H), (3) [Formula] and (4) [Formula] However, in the above formulas (1) to (4), the definition of R is the same as above, and either Y ₁ or Y ₂ represents a hydroxyl group, and the other represents a chlorine atom or a bromine atom. or an atomic group; n represents the average degree of polymerization and is 0 or a positive number greater than 0; at least 40% of the total terminal groups (sum of T ₁ and T ₂ ) are: α-glycol group A method for producing a vinyl ester resin, which comprises reacting an α-glycol resin with a polymerizable unsaturated monobasic acid. 2 The ratio of α-glycol resin and polymerizable unsaturated monobasic acid used per 1 mole of α-glycol resin,
The method according to claim 1, wherein the amount is 0.2 to 2.2 moles of the polymerizable unsaturated monobasic acid. 3. The method according to claim 1, wherein 90% or more of all terminal groups of the α-glycol resin used are α-glycol groups. 4. The reaction was carried out in the presence of an esterification catalyst at 80 to 180
2. A method according to claim 1, which is carried out at a temperature in the range of °C. 5. The method according to claim 1, wherein oxygen or an oxygen-containing gas is bubbled into the reaction system. 6. The method according to claim 1, wherein the reaction is carried out in the presence of a reaction solvent. 7. The method according to claim 6, wherein the reaction solvent is an ethylenically unsaturated group-containing monomer copolymerizable with the vinyl ester resin.