JPH0643455B2 - Process for producing N- (hydroxyphenyl) maleimide copolymer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application] The present invention relates to a method for producing an N- (hydroxyphenyl) maleimide copolymer, more specifically, by copolymerizing maleic anhydride and an unsaturated hydrocarbon compound. The present invention relates to a method for producing an N- (hydroxyphenyl) maleimide copolymer by reacting the obtained copolymer with an aminophenol in an organic solvent to modify the copolymer. .

The N- (hydroxyphenyl) maleimide copolymer obtained by the production method of the present invention is soluble in an organic solvent such as dimethylformamide, cyclohexanone, tetrahydrofuran, and ethyl cellosolve, and thus is useful as a thin film coating resin, and is phenol. Since it has a soluble hydroxyl group, it is soluble in an alkaline aqueous solution, and therefore it is useful as a base polymer for photosensitive resins and can be used in a wide range of applications as heat-resistant resins.

[Conventional technology]

As a method for producing a copolymer containing N- (hydroxyphenyl) maleimide as a component, Polymer Chemistry, Vol. 26, 598
Page (1969), N- (p- synthesized by transesterification via maleimide with hydroxyl group esterified.
A method of synthesizing a hydroxyphenyl) maleimide monomer and styrene to synthesize an N- (p-hydroxyphenyl) maleimide-styrene copolymer having a slightly large number of structural units based on N- (p-hydroxyphenyl) maleimide is shown. Also, in the 7th Photopolymer Conference (SPE sponsored by Ellenville, NY) Proceedings, p. 35 (1985), N- (p-acetoxyphenyl) maleimide monomer with esterified para hydroxyl group and styrene. There is shown a method for synthesizing an N- (p-hydroxyphenyl) maleimide-styrene copolymer (composition ratio 1: 1), in which and are copolymerized with each other and then subjected to a transesterification reaction.

In the above-mentioned method for producing a conventionally known N- (p-hydroxyphenyl) maleimide-styrene copolymer, a step of converting the esterified hydroxyl group at the monomer or polymer stage to a hydroxyl group by a transesterification reaction is necessary.
It is because the above-mentioned N
This is because it is impossible to produce an imide compound having a hydroxyl group such as a-(p-hydroxyphenyl) maleimide monomer.

Generally, as a method for producing an imide compound, pyridine as a catalyst, triethylamine, a base such as sodium acetate,
And, as a dehydrating agent, acetic anhydride, propionic anhydride, using an acid anhydride such as benzoic anhydride, a method of reacting an amino compound with an acid anhydride such as maleic anhydride is well known, this method For example, when applied to the production of maleimide monomers of aminophenols and maleic anhydride, the hydroxyl groups of aminophenols are esterified, and imide compounds having hydroxyl groups cannot be produced in high yield.

Therefore, in the conventionally known method for producing N- (p-hydroxyphenyl) maleimide-styrene copolymer, in order to return the hydroxyl group esterified at the monomer or polymer stage to the hydroxyl group by the transesterification reaction, for example, Belgium is usually used. As disclosed in Japanese Patent No. 613801, a method of transesterification of maleimide in which a hydroxyl group is esterified is adopted.

[Problems to be solved by the invention]

The above-mentioned conventional method for producing N- (p-hydroxyphenyl) maleimide-styrene copolymer requires a step of converting the esterified hydroxyl group at the monomer or polymer stage to a hydroxyl group by a transesterification reaction as described above. Since this transesterification reaction requires a long time, it is an industrially very disadvantageous method from the viewpoint of economical efficiency, and moreover, when a maleimide monomer is produced from aminophenol and maleic anhydride, Since the unsaturated double bond is attacked by aminophenol, there is a problem that a copolymer of the maleimide monomer and styrene cannot be synthesized in high yield.

Therefore, the object of the present invention is to provide N- (hydroxyphenyl)
PROBLEM TO BE SOLVED: To provide a process for producing an N- (hydroxyphenyl) maleimide copolymer, which allows a maleimide copolymer to be synthesized very easily in a high yield while retaining a hydroxyl group without undergoing a transesterification reaction step. To do.

[Means for solving problems]

The present invention has the above-mentioned object of providing a copolymer of maleic anhydride and an unsaturated hydrocarbon compound with a compound of formula (I) (In the formula, R is a halogen atom or a lower alkyl group having 1 to 5 carbon atoms, and n is a number of 1 to 4.) by reacting with an aminophenol represented by , Formula (II) (In the formula, R and n are the same as in the case of the formula (I).), The formula (III) And formula (IV) (In the formula, R ₁ is an aryl group, an alkyl group having _{1 to} 16 carbon atoms or a cycloalkyl group, R ₂ is hydrogen or a lower alkyl group, and l, m and n are each represented by the formula ( II), the number of repeating units of formula (III) and formula (IV) (integer), and the ratio of n to (l + m) and l to (l
+ M) Preferably Is. ] An N- (hydroxyphenyl) maleimide copolymer having a structural unit represented by
This has been achieved by providing a method for producing a (hydroxyphenyl) maleimide copolymer.

The method for producing the N- (hydroxyphenyl) maleimide copolymer of the present invention is described in detail below.

The copolymer of maleic anhydride and an unsaturated hydrocarbon compound used in the production method of the present invention (hereinafter referred to as maleic anhydride copolymer) has the formula (V) And formula (VI) (In the formula, R ₁ is an aryl group, an alkyl group having _{1 to} 16 carbon atoms or a cycloalkyl group, R ₂ is hydrogen or a lower alkyl group, and a and b are each of the formula (V). And the number of repeating units of formula (VI) (integer), and the ratio of a to b is Preferably Is. ) Is a copolymer having a structural unit represented by, and suitable unsaturated hydrocarbon compounds include, for example, styrene,
Examples thereof include α-methylstyrene, vinylnaphthalene, isobutylene, 3-methylbutene-1, hexene-1, vinylcyclohexane and the like.

In the maleic anhydride copolymer, the ratio (b / a) of the structural unit represented by the above formula (V) and the structural unit represented by the above formula (VI) is such that the target N- (hydroxyphenyl) maleimides It is the same as the ratio [n / (l + m)] of the structural unit represented by the formula (II) and the structural unit represented by the formula (III) to the structural unit represented by the formula (IV) in the copolymer. When this ratio exceeds 10, the property is almost the same as that of a homopolymer of an unsaturated hydrocarbon compound, there is no heat resistance, and N- (hydroxyphenyl) maleimides which cannot be used as a base polymer of a photosensitive polymer are used. Not suitable because only polymers can be produced. On the other hand, if the ratio b / a is too small, the coating film of the N- (hydroxyphenyl) maleimide copolymer becomes weak or brittle, which is not suitable.

The maleic anhydride copolymer preferably has a number average molecular weight (▲ ▼) of 1,000 to 500,000.

The aminophenols represented by the formula (I) used in the method of the present invention include, for example, 3-methyl-
p-aminophenol, 2-methyl-p-aminophenol, 4-chloro-o-aminophenol, 2-chloro-p-aminophenol, 4-aminocatechol, 5-
Amino-2-hydroxy-p-xylene-3,5-dibromo-4-aminophenol and the like can be mentioned,
It is preferable that n in the formula (I) is 1 to 2.

The ratio of the maleic anhydride copolymer to the aminophenols used is preferably 1 mol with respect to 1 mol of the maleic anhydride component [the structural unit represented by the formula (V)] in the maleic anhydride copolymer. Aminophenols are 10 mol or less, more preferably 2 mol or less.

As the organic solvent used as the reaction solvent in the present invention, various polar solvents can be used, and specifically, dimethylformamide, dimethylsulfoxide, N-
Methyl-2-pyrrolidone, hexamethylenephosphoramide, cyclohexanone and the like can be mentioned.

The amount of the organic solvent used varies depending on the molecular weight of the maleic anhydride copolymer used and the solubility in the solvent, but is usually 10 to 200 per 10 g of the maleic anhydride copolymer.
ml, preferably 20-100 ml.

Thus, as a preferred embodiment of the production method of the present invention, for example, (1) a maleic anhydride copolymer and aminophenols are added in an organic solvent such as dimethylformamide in an amount of 40 to 150.
C., preferably at a reaction temperature of 50 to 100.degree. C., for 1 to 20 hours to convert a part or all of the maleic anhydride component to an N- (hydroxyphenyl) maleamic acid component, and then a tertiary amine catalyst. And an azeotropic solvent such as toluene or xylene for removing water generated by cyclization dehydration, and the mixture is added at 80 to 200 ° C., preferably 1
A method for obtaining an N- (hydroxyphenyl) maleimide copolymer by cyclization dehydration reaction at a reaction temperature of 00 to 150 ° C. for 1 to 20 hours, (2) a maleic anhydride copolymer and aminophenols are dimethyl 40 to 150 ° C., preferably 50 to 100, in the presence of a tertiary amine catalyst in an organic solvent such as formamide.
The reaction is carried out at a reaction temperature of ° C for 1 to 20 hours, and then an azeotropic solvent such as toluene or xylene is added to the reaction mixture to obtain a temperature of 80 to 200
1-2 at a reaction temperature of 100 ° C to 150 ° C, preferably 100 ° C to 150 ° C.
A method of obtaining a N- (hydroxyphenyl) maleimides copolymer by reacting for 0 hours and subjecting a part or all of the maleic anhydride component to a cyclization dehydration reaction via N- (hydroxyphenyl) maleamic acids. , (3) Maleic anhydride copolymer and aminophenols in an organic solvent such as dimethylformamide in the presence of a tertiary amine catalyst and an azeotropic solvent such as toluene or xylene.
To 200 ° C., preferably 100 ° C. to 150 ° C. for 1 to 20 hours, and a part or all of the maleic anhydride component is subjected to a cyclodehydration reaction via N- (hydroxyphenyl) maleamic acids. Examples thereof include a method for obtaining an N- (hydroxyphenyl) maleimide copolymer.

In any of the above embodiments (1) to (3), the azeotropic solvent is not used during the cyclization dehydration reaction, and the azeotropic solvent is 100 to 20.
The water generated at the reaction temperature of 0 ° C. can be removed, and the circulation of nitrogen gas can effectively carry out the dehydration reaction.

Examples of the tertiary amine catalyst used in the reaction of the above maleic anhydride copolymer and aminophenols include:
For example, triethylamine, tri-n-propylamine, tri-n-butylamine, tri-i-butylamine, tri-n-pentylamine, tri-n-hexylamine, tri-n-octylamine, pyridine, N-ethylmorpholine. , N-dimethylbenzylamine, isoquinoline and the like.

The amount of these tertiary amine catalysts used is 0.01 mol based on 1 mol of the maleic anhydride component in the maleic anhydride copolymer.
˜2 mol, particularly 0.1 to 1 mol is preferred.

Further, examples of the azeotropic solvent used for removing the water generated in the above-mentioned cyclization dehydration reaction include benzene, toluene, xylene and the like.

The amount of these azeotropic solvents used is such that 1 mol of water is produced from 1 mol of the N- (hydroxyphenyl) maleamic acid component produced by the reaction between the maleic anhydride component and the aminophenols in the maleic anhydride copolymer. Therefore, it is sufficient that the produced water is azeotropically removed, and it is usually preferable to separate the azeotropically removed water from the azeotropically removed water and use it under reflux.
The volume ratio of the reaction solvent to the azeotropic solvent is preferably 1: 1 or less,
More preferably, it is 1: 0.5 or less.

The above-mentioned azeotropic solvent may be added in a necessary amount in several portions according to the progress of the reaction, or may be refluxed while azeotropically removing water.

In the production method of the present invention, when the reaction between the maleic anhydride copolymer and the aminophenols is carried out in two steps as in the above embodiments (1) and (2), the maleic anhydride copolymer and the aminophenol are used. The reaction temperature of the first-step reaction for producing a copolymer of N- (hydroxyphenyl) maleamic acid by the reaction of the compounds is in the range of 40 to 150 ° C., particularly 5
It is preferably in the range of 0 to 100 ° C. If the temperature is lower than 40 ° C, the reaction rate is extremely low and the reaction hardly progresses.
On the other hand, if the temperature exceeds 150 ° C., the water produced by the cyclodehydration of partially produced N- (hydroxyphenyl) maleamic acids is likely to react with an unreacted anhydrous ring, or a side reaction due to a hydroxyl group is likely to occur, which is not preferable.

In addition, the reaction temperature of the second step reaction for cyclodehydration of the N- (hydroxyphenyl) maleamic acid copolymer, and the maleic anhydride copolymer and aminophenol as in the case of the above embodiment (3). The reaction temperature when the reaction with the compounds is carried out in one step in the presence of a tertiary amine and an azeotropic solvent for dehydration is in the range of 80 to 200 ° C., particularly 100 ° C.
It is preferably in the range of to 150 ° C. If the temperature is lower than 80 ° C, the reaction rate is extremely low and the reaction hardly progresses. If the temperature is higher than 200 ° C, side reaction or intermolecular reaction due to hydroxyl group is likely to occur, which is not preferable.

Further, in the production method of the present invention, the reaction time between the maleic anhydride copolymer and the aminophenols is the reaction temperature, the amount of the aminophenols used, and the desired reaction rate (anhydrous in the maleic anhydride copolymer. Degree of modification of maleic acid component into N- (hydroxyphenyl) maleimides], etc., but usually 1 in the first-step reaction for producing a copolymer of N- (hydroxyphenyl) maleamic acid.
-20 hours, and 1-20 hours in the second stage reaction in which the copolymer is cyclodehydrated.

The reaction time in the case of carrying out the reaction in one step in the presence of the tertiary amine and the azeotropic solvent is usually 1 to 20 hours.

In the production method of the present invention, the content of the constituent units of N- (hydroxyphenyl) maleimides in the target N- (hydroxyphenyl) maleimide copolymer is controlled by controlling the amount of aminophenols used, the reaction temperature and the reaction. This can be easily performed by appropriately selecting the time.

After the completion of the reaction, the N- (hydroxyphenyl) maleimide copolymer can be easily recovered from the reaction solution by precipitating the polymer using an inert solvent such as water or ethers.

The N- (hydroxyphenyl) maleimide copolymer of the present invention obtained as described above is soluble in an organic solvent such as dimethylformamide, cyclohexanone, tetrahydrofuran, ethyl cellosolve, etc., and thus is useful as a thin film coating resin. In addition, since it has a phenolic hydroxyl group and is soluble in an alkaline aqueous solution, it is useful as a base polymer for a photosensitive resin and can be used in a wide range of applications as a heat resistant resin.

〔Example〕

Hereinafter, the present invention will be described in more detail with reference to Examples of the present invention. In the following examples, the modification rate of the maleic anhydride component in the maleic anhydride copolymer to N- (hydroxyphenyl) maleimides was determined by calculating the total amount of nitrogen in elemental analysis, and Of maleic anhydride component Indicated by. The infrared absorption spectrum is a polystyrene conversion value obtained by the KBr tablet method, and the number average molecular weight (▲ ▼) is a standard polystyrene calibration curve obtained by the GPC method using tetrahydrofuran as a solvent. Further, the glass transition temperature (Tg) is measured by DuPont 990 Thermal Analyzer DSC.
It was measured by.

Example 1 A 200 ml four-necked flask equipped with a stirrer, a thermometer, a moisture metering receiver and a nitrogen inlet tube was placed in a maleic anhydride-styrene copolymer (copolymerization ratio 1: 1; a product manufactured by Kawara Yuka Co., Ltd. 10 g of SMA-1000) and 50 ml of dehydrated dimethylformamide were added and dissolved by stirring, and then 3-methyl-p-
Aminophenol (9.1 g) was added and dissolved, and the reaction was carried out as a first-stage reaction at 80 ° C. for 2 hours with stirring, and N- (2
-Methyl-p-hydroxyphenyl) maleamic acid copolymer is produced, and then tri-n is used as a second stage reaction.
-Add butylamine 3.1g and toluene 15ml,
Water generated by the cyclization dehydration reaction was azeotroped with toluene while flowing nitrogen gas at ℃, and 10 ml of toluene was added after 1 hour while taking it out of the reaction system. After that, toluene was refluxed by overflowing from the moisture quantitative receiver. Then, the cyclization dehydration reaction was carried out for 4 hours.

After the reaction is completed, cool the temperature of the solution to 40 ° C. or lower,
The polymer was precipitated by adding into 300 ml of ethyl ether. After standing, the supernatant was removed, the precipitated polymer was washed with 200 ml of ethyl ether, dissolved in 150 ml of THF, and then the solution was gradually added dropwise to 700 ml of ethyl ether to precipitate a powdery polymer. Then, the polymer was separated, dissolved again in THF-ethyl ether, and purified by precipitation, and dried in vacuum at 100 ° C. for 24 hours to give an N- (2-methyl-p-hydroxyphenyl) maleimide-styrene copolymer. Obtained.

The polymer yield was 11.6 g, and the elemental analysis value was C73.35% H5.80% N4.60% (74.24) (5.59) (4.56) [The values in parentheses are theoretical values when the modification rate is 100%] Therefore, 100% of the maleic anhydride component of the maleic anhydride-styrene copolymer was modified with the N- (2-methyl-p-hydroxyphenyl) maleimide component. Also, ▲
▼ was 4,890 and Tg was 220 ° C.

The infrared absorption spectrum is shown in FIG. As shown in Fig. ¹ , phenolic OH, 1700 at 3400 cm ^-1
cm ^-1 imide carbonyl group, absorption of the phenyl group of the styrene component was observed in 700 cm ^-1.

Example 2 A 200 ml four-necked flask equipped with a stirrer, a thermometer, a moisture metering receiver, and a nitrogen inlet tube was used, and 20 g of the same maleic anhydride-styrene copolymer as used in Example 1 and dehydrated dimethylformamide were used. After adding 100 ml and stirring to dissolve, 21.3 g of 4-chloro o-aminophenol was added and dissolved, and reacted as a first-stage reaction at 80 ° C. for 9 hours with stirring, and N- (3-chloro- o-Hydroxyphenyl) maleamic acid copolymer is produced, and then, as a second-stage reaction, 6.1 g of tri-n-butylamine and 30 ml of toluene are added, and water generated by the cyclization dehydration reaction is carried out at 140 ° C. while passing nitrogen gas. Was azeotroped with toluene and taken out of the reaction system, 1 hour later, 20 ml of toluene was added, and then toluene was refluxed by overflowing from the moisture quantitative receiver. Then, the cyclization dehydration reaction was carried out for 4 hours.

After completion of the reaction, the same treatment as in Example 1 was carried out to obtain an N- (3-chloro-o-hydroxyphenyl) maleimide-maleic anhydride-styrene copolymer.

The measurement results of the yield and various physical properties of this copolymer are shown in Table 1 below.
And the infrared absorption spectrum is shown in FIG.

As shown in Fig. 2, 3400 cm ^-1 phenolic OH, 1
Carbonyl groups of the imide to 700 cm ^-1, absorption of the phenyl group of the styrene component was observed in 700 cm ^-1.

Example 3 A maleic anhydride-styrene copolymer was converted into maleic anhydride-
Instead of an isobutylene copolymer (copolymerization ratio 1: 1, Kuraray Isoprene Chemical Co., trade name Isoban-04), the amount of 3-methyl-p-aminophenol used was 12 g.
N- (2-methyl-) in the same manner as in Example 1 except that
A p-hydroxyphenyl) maleimide-maleic anhydride-isobutylene copolymer was obtained.

The measurement results of the yield and various physical properties of this copolymer are shown in Table 1 below.
And the infrared absorption spectrum is shown in FIG.

As shown in Fig. 3, phenolic OH at 3400 cm ^-1 ,
Carbonyl groups of the imide to 1700 cm ^-1, absorption of methyl group of isobutylene was observed in 2950 cm ^-1.

Example 4 N- (3,5-dichloro-p-hydroxyphenyl) was prepared in the same manner as in Example 3 except that 17.3 g of 2,6-dichloro-4-aminophenol was used as the aminophenol.
A maleimide-maleic anhydride-isobutylene copolymer was obtained.

The measurement results of the yield and various physical properties of this copolymer are shown in Table 1 below.
And the infrared absorption spectrum is shown in FIG.

As shown in Fig. 4, phenolic OH at 3400 cm ^-1 ,
Carbonyl groups of the imide to 1700 cm ^-1, absorption of methyl group of isobutylene was observed in 2950 cm ^-1.

[Effects of the Invention] According to the process for producing an N- (hydroxyphenyl) maleimide copolymer of the present invention, it is useful as a base polymer such as a photosensitive resin, and further used in a wide range of applications as a heat resistant resin. It is possible to synthesize an N- (hydroxyphenyl) maleimide copolymer that can be obtained very easily in a high yield while retaining a hydroxyl group without undergoing a transesterification reaction step. It is easy to control the content of the constituent units of N- (hydroxyphenyl) maleimides in the hydroxyphenyl) maleimide copolymer, and the production method of the present invention is an industrially extremely advantageous production method.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 shows an infrared absorption spectrum chart of the N- (2-methyl-p-hydroxyphenyl) maleimide-styrene copolymer obtained in Example 1, and FIG. Example 2
FIG. 3 is a chart of infrared absorption spectrum of the N- (3-chloro-o-hydroxyphenyl) maleimide-maleic anhydride-styrene copolymer obtained in FIG. 3, and FIG. 3 shows N- (obtained in Example 3). FIG. 4 shows an infrared absorption spectrum chart of a 2-methyl-p-hydroxyphenyl) maleimide-maleic anhydride-isobutylene copolymer, and FIG. 4 shows N- (3,5-dichloro-p obtained in Example 4). 1 shows an infrared absorption spectrum chart of a -hydroxyphenyl) maleimide-maleic anhydride-isobutylene copolymer.

Claims (3)

[Claims] 1. A copolymer of maleic anhydride and an unsaturated hydrocarbon compound, and a compound of formula (I) (In the formula, R is a halogen atom or a lower alkyl group having 1 to 5 carbon atoms, and n is a number of 1 to 4.) and is reacted with an aminophenol represented by the following formula in an organic solvent. , Formula (II) (In the formula, R and n are the same as in the case of the formula (I).), The formula (III) And formula (IV) (In the formula, R ₁ is an aryl group, an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group, and R ₂ is hydrogen or a lower alkyl group. Further, m and n are respectively represented by the formula (II ), The number of repeating units of formula (III) and formula (IV) (integer)
And the ratio between n and (l + m) and the ratio between l and (l + m) are respectively Is. ] An N- (hydroxyphenyl) maleimide copolymer having a structural unit represented by
Process for producing (hydroxyphenyl) maleimide copolymer. 2. The method for producing an N- (hydroxyphenyl) maleimide copolymer according to claim 1, wherein the unsaturated hydrocarbon compound is styrene. 3. The method for producing an N- (hydroxyphenyl) maleimide copolymer according to claim 1, wherein the unsaturated hydrocarbon compound is isobutylene.