JP2745743B2 - Method for producing reactive polymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to a method for producing a reactive polymer having an epoxy group.

In particular, the present invention relates to a method for producing a polymer of an α-methylstyrene derivative having an epoxy group, which is useful in various uses such as a coating material, an adhesive, a resin for FRP (fiber reinforced resin), and a resin modifier.

<Prior art> An α-methylstyrene derivative having an epoxy group is first produced by a method of polymerizing an α-methylstyrene derivative having a phenolic hydroxyl group using a cationic catalyst, and then glycidyl etherifying this with epichlorohydrin. I was

Synthetic Organic Chemistry, 26 (12), 66 (1968) describes a method for obtaining poly (vinylphenyl glycidyl ether) by radical polymerization of vinylphenyl glycidyl ether.

However, an α-methylstyrene derivative having an epoxy group does not undergo radical polymerization probably due to the presence of an α-methyl substituent.

JP-A-61-293209 and JP-A-62-197405 disclose that poly (isopropenylphenyl glycidyl ether), a kind of an α-methylstyrene derivative having an epoxy group, has As a method for selectively cationically polymerizing only a propenyl group, a method using hydrogen iodide, hydrogen iodide / iodine, or halogen as a catalyst is disclosed.

<Problem to be Solved by the Invention> In a method of glycidyl etherifying a polymer of an α-methylstyrene derivative having a phenolic hydroxyl group with epichlorohydrin, in addition to the target substance, chlorine groups having various structures derived from epichlorohydrin are used. A polymer having a bond composed of —OCH ₂ —CH (OH) —CH ₂ O between molecules (hereinafter referred to as a hydroxyether bond), a polymer having an unreacted hydroxyl group portion, and the like are produced as by-products.

When these by-products are contained, there are problems such as a large amount of hydrolyzable chlorine, low heat resistance and low water resistance due to low crosslinking density when used as an epoxy resin.

In the methods disclosed in JP-A-61-293209 and JP-A-62-197405, a polymer containing a hydrolyzable halogen is obtained.

The present invention provides an advantageous method for producing an α-methylstyrene derivative having an epoxy group containing less components which cause these drawbacks and problems.

<Means for Solving the Problems> The present invention provides an α-methylstyrene derivative having an epoxy group in the presence of a catalyst comprising acetic acid or an acetic acid derivative and a divalent metal halide, or sulfone as a catalyst. This is a method for producing a reactive polymer, which is polymerized in the presence of an acid.

Representative examples of the α-methylstyrene derivative having an epoxy group according to the present invention include nuclear-substituted or unsubstituted isopropenylphenylglycidyl ethers.

In the general formula, (In the formula, R ₁ , R ₂ , R ₃ and R ₄ are each a group selected from a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms and a phenyl group.)

Examples of the isopropenyl phenyl glycidyl ether represented by the general formula include o-isopropenyl phenyl glycidyl ether, m-isopropenyl phenyl glycidyl ether, p-isopropenyl phenyl glycidyl ether, 2,6-dimethyl-4-isopropenyl Phenyl glycidyl ether, 2,6-dibromo-4-isopropenyl phenyl glycidyl ether, 2-phenyl-4-isopropenyl phenyl glycidyl ether and the like can be mentioned.

Of these, p-isopropenylphenyl glycidyl ether is easily available as a raw material.

These isopropenyl phenyl glycidyl ethers can be used alone or in combination of two or more.

The α-methylstyrene derivative having an epoxy group can be obtained by reacting an α-methylstyrene derivative having a phenolic hydroxyl group with epichlorohydrin.

As this method, for example, as disclosed in JP-A-58-189223, a generally known method for producing a glycidyl ether of a phenol from a monohydric or polyhydric phenol can be applied.

The α-methylstyrene derivative having an epoxy group obtained by these methods can be used as it is.

However, when the glycidyl ether is used as a raw material for an epoxy resin, it is desirable that the amount of by-products be small.

By this purification, the oligomer component and the by-product chlorine-containing derivative can be removed to an arbitrary amount.

Especially when used as an epoxy resin for electronic materials,
It is desirable that the purity is 98.7% by weight or more and the chlorine-containing derivative is 0.8% by weight or less.

Needless to say, the higher the purity, the higher the heat resistance and water resistance when used as an epoxy resin, and the smaller the chlorine-containing derivative, the smaller the amount of hydrolyzable chlorine.

In the polymerization of the α-methylstyrene derivative having an epoxy group, another unsaturated monomer may be copolymerized. The unsaturated monomer is a cationically polymerizable compound having at least one carbon-carbon double bond, for example, styrenes such as α-methylstyrene, methoxystyrene, vinyltoluene; methyl vinyl ether, ethyl vinyl ether, isobutyl vinyl ether Vinyl ethers such as 1,2-chloroethyl vinyl ether and 2-acetoxyethyl vinyl ether; conjugated dienes such as butadiene, isoprene and cyclopentadiene; cyclic unsaturated compounds such as indene; and aliphatic olefins such as isobutylene.

One of the catalysts is a combination system of acetic acid or a derivative thereof and a halide of a divalent metal.

Acetic acid or a derivative thereof is a cation source, and specifically, acetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid, isobutyroxyethyl acetate (CH ₃ CH (OiB
It is at least one selected from the u) -OCOCH _3).

 Phosphoric acid can also be used as a cation source.

As the divalent metal halide, a zinc or tin halide is preferable.

Among them, it is at least one selected from zinc iodide (ZnI ₂ ), zinc bromide (ZnBr ₂ ), zinc chloride (ZnCl ₂ ), and stannous chloride (SnCl ₂ ).

The amount of acetic acid or a derivative thereof used is from 0.01 mol% to 20 mol% based on the total number of moles of the monomer.

If the amount is less than 0.01 mol%, the polymerization reaction is slow.

The amount of the divalent metal halide to be used may be excessive or too small with respect to the amount of acetic acid or a derivative thereof, but is preferably used in an amount equivalent to acetic acid or a derivative thereof in an equimolar amount, and at most 4 times. Good up to mole.

If the amount of the divalent metal halide is larger than this, side reactions increase, which is not preferable.

 Sulfonic acids are used as another catalyst.

Specifically, it is at least one selected from methanesulfonic acid, trifluoromethanesulfonic acid, and toluenesulfonic acid.

The amount of the sulfonic acids used is from 0.01 mol% to 20 mol% based on the total number of moles of the monomers.

If the amount is less than 0.01 mol%, the polymerization reaction is slow.

At the time of polymerization, a solvent used in usual cationic polymerization can be used.

For example, aromatic hydrocarbons, halogenated hydrocarbons, nitrated hydrocarbons and the like can be mentioned.

Specifically, benzene, toluene, dichloromethane,
1,2-dichloroethane, nitroethane and the like.

In particular, when sulfonic acids are used as the catalyst,
Those having a dielectric constant of 7 to 40 are desirable. For example, halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane and nitroethane, and nitrated hydrocarbons.

The polymerization temperature is preferably −100 ° C. to 30 ° C., and −80 ° C. to 0 ° C.
Is more preferred.

 If the temperature exceeds 30 ° C., the polymerization yield decreases.

Further, even if the temperature is lowered below -100 ° C, the effect is small, which is industrially disadvantageous and is not preferred.

The polymer obtained by the method of the present invention can be cured by adding a curing agent similarly to a conventional epoxy resin,
It can also be used for similar applications.

Known curing agents can be used, for example, amine types such as amines and polyamides; acid types such as acid anhydrides; polyphenol types such as phenol novolak, polyvinyl phenol and polyisopropenyl phenol; boron trifluoride complex And Lewis acid types.

Applications include paints, semiconductor encapsulants, adhesives, FRP resins such as printed circuit boards, resin modifiers, and the like.

<Effects of the Invention> The present invention uses a specific catalyst for a substance having two types of functional groups of an unsaturated double bond group and an epoxy group in one molecule, such as an α-methylstyrene derivative having an epoxy group. Thus, the reaction of the epoxy group is suppressed, and the polymerization is carried out only with the unsaturated double bond group.

In general, such a polymer of an α-methylstyrene derivative having an epoxy group of a vinyl polymerization type is obtained by a reaction between a polymer of an α-methylstyrene derivative having a phenolic hydroxyl group and epichlorohydrin.From this method, epichlorohydrin is converted to epichlorohydrin. It was difficult to remove the coexisting chlorinated substances.

However, in the present invention, since the α-methylstyrene derivative having an epoxy group can be purified by a conventional technique such as rectification or recrystallization, an α-methylstyrene derivative having an epoxy group having a small impurity content can be obtained. Above, during polymerization, the production of halides derived from the catalyst can be suppressed,
A polymer of an α-methylstyrene derivative having a higher purity epoxy group can be obtained.

<Examples> Hereinafter, the present invention will be described with reference to examples, but the present invention is not limited thereto.

The epoxy equivalent in the present invention is defined as a gram equivalent per mole of glycidyl ether group.

Further, the chlorine content means that a polymer of an α-methylstyrene derivative having an epoxy group is dissolved in dioxane, an alcohol solution of potassium hydroxide is added, and chlorine ions which are desorbed when heated under reflux for 2 hours are converted into silver nitrate. It is quantified by back titration in a solution and is defined as the weight percentage of chlorine atoms in the compound.

Number average molecular weight Mn and weight average molecular weight Mw of the polymer,
gel. Permission. Using a chromatograph (manufactured by Shimadzu Corporation, LC-6A), it was determined from a calibration curve using standard polystyrene.

¹ H-NMR spectrum was measured by JEOL FX-
Measured at 90Q.

The residual iodine content was measured by elemental analysis.

Reference Example (1) Synthesis of crude p-isopropenylphenylglycidyl ether 1 equipped with a thermometer, a separation tube, a dropping funnel, and a stirrer
In a liter flask, p-isopropenylphenol (1
134 g and 2.5 mol of oligomer 9) and 7.0 mol of epichlorohydrin were added to obtain a homogeneous solution.

At a temperature of 74 ° C. and a pressure of 250 mmHg, a 48% aqueous NaOH solution was continuously added over 6 hours.

During this time, epichlorohydrin and water were azeotropically liquefied, separated into an organic layer and an aqueous layer by a separation tube, the aqueous layer was removed outside the system, and the organic layer was circulated in the system.

After the completion of the reaction, the temperature was maintained for 1 hour, unreacted epichlorohydrin was removed by evaporation, and the reaction product was dissolved in methyl isobutyl ketone.

Next, after by-product salts were filtered off, methyl isobutyl ketone was removed by evaporation to obtain solid crystals at room temperature.

Epoxy equivalent of this is 201, chlorine content is 830ppm
Met.

In the analysis by GC-Mass (gas chromatograph-mass spectrometer, JEOL Ltd. DX-800) and (gel permeation chromatograph (Nihon Bunko Kogyo TRIROTAR-SR II)), p-isopropenylphenyl glycidyl ether 80.95. % Of the oligomer, 14.7% by weight of the oligomer, and 0.42% by weight of the chlorine-containing dielectric material of p-isopropenylphenyl.

(2) Purification of p-isopropenylphenyl glycidyl ether 100 g of crude p-isopropenyl phenyl glycidyl ether obtained in (1) was separated by a rectification column having 10 theoretical plates, and then 120 ° C to 122 ° C at 1.8 Torr. 67 g of a fraction up to

 This fraction became white crystals at room temperature.

The epoxy equivalent was 190 and the chlorine content was 30 ppm.

According to GC-Mass analysis, the purity of p-isopropenylphenyl glycidyl ether was 99.95% by weight, and the content of the chlorine-containing derivative of p-isopropenylphenyl was 0.01% by weight.

Examples 1 and 2 Comparative Examples 1 and 2 The p-isopropenylphenyl glycidyl ether obtained in Reference Example (2) was used as a raw material and dissolved in purified dichloromethane.

The catalysts shown in Table 1 were prepared as a dichloromethane solution.

In a test tube equipped with a three-way cock under dry N ₂ , a raw material, a solution of a catalyst and dichloromethane were added so as to have the concentrations shown in Table 1, and polymerization was carried out at -78 ° C.

After completion of the polymerization, the reaction was stopped with a cold ammonia-methanol solution, washed with a 10% aqueous sodium thiosulfate solution and pure water, and the solvent was recovered by distillation under reduced pressure to obtain a polymer.

 The obtained polymer was soluble in chloroform.

In addition, ¹ H-NMR confirmed that only the isopropenyl group was polymerized.

Yield of the obtained polymer, average molecular weight, molecular weight distribution,
The residual iodine content was measured and calculated.

 Table 1 shows the results.

Comparative Example 3 Polymerization was carried out in the same manner as in Example except that the catalyst used was a metal halide shown in Table 1.

The obtained polymer was completely insoluble in chloroform.

Examples 3 to 8 The p-isopropenylphenyl glycidyl ether obtained in Reference Example (2) was used as a raw material and dissolved in purified dichloromethane.

The catalysts shown in Table 2 were prepared as dichloromethane solutions.

Under dry N ₂ , a raw material, a solution of a catalyst and dichloromethane were added to a test tube equipped with a three-way cock so as to have the concentrations shown in Table 2, and polymerization was carried out at -78 ° C.

After completion of the polymerization, the reaction was stopped with a cold ammonia-methanol solution, washed with a 10% aqueous sodium thiosulfate solution and pure water, and the solvent was recovered by distillation under reduced pressure to obtain a polymer.

 The obtained polymer was soluble in chloroform.

In addition, ¹ H-NMR confirmed that only the isopropenyl group was polymerized.

Yield of the obtained polymer, average molecular weight, molecular weight distribution,
The residual iodine content was measured and calculated.

 Table 2 shows the results.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Noriaki Saito, Inventor No. 5-1 Sokai-cho, Niihama-shi, Ehime Sumitomo Kagaku Kogyo Co., Ltd. Gaku Kogyo Co., Ltd. (56) References JP 6-96613 (JP, B2) JP 6-2784 (JP, B2)

Claims (7)

(57) [Claims] (1) General formula Wherein R ₁ , R ₂ , R ₃ and R ₄ are each a group selected from a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms and a phenyl group. A method for producing a reactive polymer, wherein the α-methylstyrene derivative is polymerized in the presence of a catalyst comprising acetic acid or a derivative thereof and a divalent metal halide. 2. The general formula Wherein R ₁ , R ₂ , R ₃ and R ₄ are each a group selected from a hydrogen atom, a halogen atom, an alkyl group having 1 to 4 carbon atoms and a phenyl group. A method for producing a reactive polymer, wherein the α-methylstyrene derivative is polymerized in the presence of a sulfonic acid as a catalyst. 3. The method according to claim 1, wherein the α-methylstyrene derivative having an epoxy group is a substituted or unsubstituted isopropenylphenyl glycidyl ether. 4. The method according to claim 3, wherein the nucleus-substituted or unsubstituted isopropenylphenyl glycidyl ether is p-isopropenylphenyl glycidyl ether. 5. The method according to claim 1, wherein the acetic acid or a derivative thereof is at least one selected from the group consisting of acetic acid, trifluoroacetic acid, monochloroacetic acid, dichloroacetic acid, trichloroacetic acid and isobutyroxyethyl acetate. 6. The method according to claim 1, wherein the divalent metal halide is at least one selected from the group consisting of zinc iodide, zinc bromide, zinc chloride and stannous chloride. 7. The method according to claim 2, wherein the sulfonic acids are at least one selected from methanesulfonic acid, trifluoromethanesulfonic acid, and toluenesulfonic acid.