JPH031303B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to an aromatic bis-imide having excellent heat resistance and workability, and a method for producing the same. Maleimide resins represented by N,N'-(methylene-di-p-phenylene) bismaleimide are known as resins with excellent heat resistance, and are polymerized with polymaleimide resin amines, which are homopolymers of bismaleimide. It is widely used as a polymaleimide-polyamine resin in impregnated varnishes, laminates, molding materials, etc. These maleimide resins generally have sufficiently satisfactory performance in terms of heat resistance, but the melting point of the resin before curing is high, so they are used in the form of a solution, and moreover, they are usually used in the production of impregnated varnishes and laminates. It is hardly soluble in commonly used organic solvents, and N-methyl-2-pyrrolidone,
It has the disadvantage of being soluble only in polar solvents with high boiling points and strong hygroscopic properties, such as N,N-dimethylacetamide and N,N-dimethylformamide. N
- The use of impregnating varnishes prepared by dissolving them in polar solvents such as methyl-2-pyrrolidone and N,N-dimethylformamide is recommended because these solvents are expensive and both have high permeability through the skin and are highly toxic. This is undesirable from the standpoint of the working environment, safety and health, and also from the demands of the era of pollution-free living.
Additionally, the solvent tends to remain in prepregs made from varnishes prepared using these solvents, which is a major factor in reducing the performance of the intended laminate. As a result of intensive research aimed at improving these drawbacks, the present inventors discovered an aromatic bis-imide that has excellent solubility in general-purpose organic solvents and a low melting point that can be used in a solvent-free form. completed. The compound of the present invention has the general formula (I) (In the formula, A represents -SO ₂ - or -CO-,
R′ and R″ are the same or different and represent a hydrogen atom, a halogen atom, or a lower alkyl group, and D is

[expression] or

[Formula] and may be different from each other. n' and n'' are integers from 1 to 4. When n' and n'' are 2 or more, each
These compounds are novel aromatic bis-imides represented by (R' and R'' may be the same or different).These compounds are more compatible with low-boiling point solvents such as acetone, methyl ethyl ketone, and tetrahydrofuran than conventional aromatic bismaleimides. It has an extremely high solubility and a low melting point.Therefore, it has high utility value as a solvent-free varnish, and does not require a large amount of energy when producing various materials, making it a preferred energy-saving material.It is also heat resistant and has a low melting point. The cured product has good dimensional stability and moisture resistance, so these characteristics can be used in a wide range of industries such as electrical insulation materials, heat-resistant adhesives, paints, molding materials, and vulcanization aids. For example, the melting point, thermal decomposition temperature, and The solubility in organic solvents is as follows. Structural formula Melting point 125-132℃ Temperature of 5% weight loss measured on thermobalance 450℃ Organic solvent Solubility (at room temperature) N,N-dimethylformamide 50wt% or more 1,4-dioxane 50 〃 Tetrahydrofuran 50 〃 Acetone 50 〃 Methyl ethyl ketone 50 〃 Next, the manufacturing method of the present invention is based on the general formula () (In the formula, A represents -SO ₂ - or -CO-,
R′ and R″ are the same or different and represent a hydrogen atom, a halogen atom, or a lower alkyl group, and D is

[expression] or

[Formula] and may be different from each other. n' and n'' are integers from 1 to 4. When n' and n'' are 2 or more, two or more R' and R'' may be the same or different.)
The aromatic bis-amic acid represented by the general formula (I) is reacted with a dehydrating agent in the presence or absence of a solvent together with a catalyst and, if necessary, a tertiary amine. (In the formula, A, D, R', R'', n' and n'' have the same meanings as in the general formula ()). The starting material used in the production method of the present invention is a bis-amic acid compound represented by the general formula (). These compounds have the general formula () (In the formula, A, R', R'', n', n'' have the same meanings as in the general formula ()) and maleic anhydride or 5-norbornene anhydride-2,3- It is obtained by adding dicarboxylic acid in a solvent such as acetone at 0 to 40°C. To carry out the production process of the invention advantageously, the bis-amic acid obtained by the addition reaction of the diamine with maleic anhydride or 5-norbornene-2,3-dicarboxylic anhydride in an organic solvent is thus separated. It is used directly in the dehydration cyclization (imidization) reaction, which is the production method of the present invention, without any process. The aromatic diamine of the general formula () is 2-(4′-aminophenyl)-2-(4″-hydroxyphenyl)propane, 2-(3′-methyl-4′-
Aminophenyl)-2-(4″-hydroxyphenyl)propane, 2-(2′-methyl-4′-aminophenyl)-2-(4″-hydroxyphenyl)propane, 2-(3′-ethyl-4 '-aminophenyl)-2
-(4″-hydroxyphenyl)propane, 2-
(2′-propyl-4′-aminophenyl)-2-(3″
−
Hydroxyphenyl)propane, 2-(3′-aminophenyl)-2-(4″-hydroxyphenyl)propane, 2-(3′-aminophenyl)-2-(3″-
hydroxyphenyl)propane, 2-(4′-aminophenyl)-2-(3″-hydroxyphenyl)propane, 2-(5′-methyl-3′-aminophenyl)
-2-(4″-hydroxyphenyl)propane, 2
-(5′-ethyl-3′-aminophenyl)propane,
2-(3'-chloro-4'-aminophenyl)-2-
(4″-hydroxyphenyl)propane, 2-(3′,
5′-dichloro-4′-aminophenyl)-2-(4″-
Hydroxyphenyl)propane, 2-(3′-bromo-4′-aminophenyl)-2-(4″-hydroxyphenyl)propane, 2-(3′,5′-dibromo-
2-(aminophenyl)-2- such as 4′-aminophenyl)-2-(4″-hydroxyphenyl)propane
(Hydroxyphenyl)propanes, 4,4'-dichlorodiphenylsulfone,
4,4'-dibromodiphenyl sulfone, 3,4'-
Dichlorodiphenyl sulfone, 3,3'-dichlorodiphenyl sulfone, 3,4'-dibromodiphenyl sulfone, 3,3'-dibromodiphenyl sulfone, 4,4'-dichlorodiphenyl ketone, 4,
4'-dibromodiphenyl ketone, 3,4'-dichlorodiphenyl ketone, 3,3'-dichlorodiphenyl ketone, 3,4'-dibromodiphenyl ketone,
1 of dihalogen compounds such as 3,3'-dibromodiphenyl ketone, 4,4'-difluorodiphenyl sulfone, and 4,4'-difluorodiphenyl ketone
Seed in the presence of an alkali metal or a basic compound such as an alkali metal hydroxide, carbonate, bicarbonate, nitrite or alcoholate in an organic solvent at 100 to 200°C. Can be done. Among such aromatic diamines, bis[p,p′-(α,α-dimethyl-p″-aminobenzyl)phenoxyphenyl]sulfone, bis[4,4′-(α,α- Dimethyl-3″-Methyl-4″-
aminobenzyl) phenoxyphenyl] sulfone, bis[p,p-(α,α-dimethyl-p″-aminobenzyl)phenoxyphenyl]ketone, bis[4,4′-(α,α-dimethyl- 3″-Methylbenzyl)phenoxyphenyl]ketone is preferred. In the method of the present invention, aromatic bis-
Amic acid is dehydrated and cyclized. The organic solvents used in the dehydration cyclization, which is the production method of the present invention, are chloroform, methylene chloride,
Halogenated hydrocarbons such as carbon tetrachloride and trichloroethylene, ketones such as acetone, methyl ethyl ketone, and cyclohexanone, formic acid, acetic acid, butyric acid,
Methyl acetate, ethyl acetate organic carboxylic acids and their esters, methyl alcohol, ethyl alcohol, propyl alcohol, ether, 1,4
- Alcohols and ethers such as dioxane, tetrahydrofuran, cellosolve, methyl cellosolve, alicyclic and aromatic hydrocarbons such as cyclohexane, benzene, toluene, xylene (o-, m-, p-), mesitylene, chlorobenzene, Aromatic compounds such as cresol (o-, m-, p-), dichlorobenzene (o-, m-, p-), acetonitrile, pyridine, N,N-dimethylacetamide, N,N-dimethylformamide, hexa Methylphosphoramide, N-methyl-
These include nitrogen-containing and sulfur-containing compounds such as 2-pyrrolidone, N-methylcaprolactam, and dimethyl sulfoxide. Particularly preferred organic solvents are acetone, methyl ethyl ketone, acetonitrile or N,N-dimethylformamide. It is also possible to use a mixture of two or more of these organic solvents. The amount of organic solvent used is preferably 1.1 to 80 times the weight of the diamine or bis-amic acid used. In addition, the catalysts used in the dehydration cyclization reaction of the production method of the present invention include sodium bicarbonate, carbonate, sulfate, nitrate, phosphate, pyrophosphate,
acetate and butyrate; bicarbonate, carbonate, sulfate, nitrate, phosphate, pyrophosphate, chloride, bromide, iodide, acetate, and butyrate of lithium; magnesium, iron (and), Carbonates of nickel (and), manganese (and), copper (and) or cobalt (and),
sulfates, phosphates, chlorides, bromides, iodides,
Hydrates and non-hydrates of formates, acetates, butyrates, stearates and naphthenates, as well as acetylacetonate complexes of copper, nickel (), cobalt (and) and manganese (and), etc. . One type of these catalysts exhibits a sufficient effect, but it is also possible to use a mixture of two or more types. Particularly preferred catalysts are sodium acetate, hydrates and non-hydrates of nickel acetate (), or hydrates and non-hydrates of cobalt acetate (). The amount of the catalyst used is in the range of 1.0 x 10 ^-3 to 1.2 mol, preferably 2.0 x 10 ^-3 to 0.5 mol, per 1 mol of bismaleamic acid used. If the amount of catalyst used is less than 1.0 x 10 ^-3 mol, the reaction rate is low and the dehydration cyclization reaction takes a long time, while if it is more than 1.2 mol, undesirable side reactions occur and bis- Imide yield decreases. Further, the tertiary amine used in the present invention is a trialkylamine having an alkyl group having 3 to 20 carbon atoms such as trimethylamine, triethylamine, tributylamine, N,N-diethylcyclohexylamine, N,N- Dimethylbenzylamine, N-methylpiperidine, 1,4-
diazabicyclo[2,2,2]-octane, 1,
8-diazabicyclo[5,4,0]-7-undecene, N-methylmorpholine, and the like. Two or more of these tertiary amines may be used in combination.
A particularly desirable tertiary amine is triethylamine. The amount of tertiary amine used is 1 bis-amide solution.
The amount is in the range of 0.01 to 1.1 mol, preferably 0.05 to 0.6 mol. If the amount of tertiary amine used is below the above range, the reaction rate will be low, while if it is above the above range, undesirable side reactions will occur. Further, the tertiary amine can also be added during the step of producing the amic acid. Furthermore, the dehydrating agent in the present invention is a compound that acts on the amic acid group of bis-amic acid to form an imide group, and is itself hydrated or hydrolyzed, or a compound that has an extremely large dehydrating ability. Typical compounds as dehydrating agents are acetic anhydride, propionic anhydride,
These are carboxylic acid anhydrides such as butyric anhydride, valeric anhydride, succinic anhydride, glutaric anhydride, benzoic anhydride, and phthalic anhydride. It is also possible to use a mixture of two or more of these dehydrating agents. A particularly preferred dehydrating agent is acetic anhydride because it is easy to handle and easy to post-process after the dehydration and cyclization reaction. The amount of the dehydrating agent used is in the range of 0.2 to 3 mol per equivalent of the amic acid group of the bis-amic acid, preferably
The amount ranges from 0.3 to 2 moles. If the amount of dehydrating agent used is less than the above range, the bis-
The residual amount of amic acid increases, and if it exceeds the above range, side reactions tend to occur. In the production method of the present invention, the reaction temperature for cyclodehydrating bis-amic acid to produce bis-imide is
It is carried out in the range of 20 to 100°C, more preferably 40°C.
In the range of ~80℃. In addition, the reaction time is 0.5 to 9
The reaction time ranges from 1 to 5 hours, more preferably from 1 to 5 hours, and the reaction proceeds under sufficient pressure to maintain the reaction system in the liquid phase. The reaction temperature is less than 20℃ or the reaction time is 0.5
If the reaction time is less than this time, the reaction rate will be so low that the reaction will hardly proceed. On the other hand, if the reaction temperature exceeds 100°C or the reaction time exceeds 9 hours, undesirable side reactions tend to occur. After the reaction under the above reaction conditions is completed, the reaction solution is cooled and a precipitant is gradually added to the resulting homogeneous phase reaction solution, or the reaction solution is dropped into the precipitant to obtain a precipitate of the desired product. However, if a precipitant such as water is added to the reaction solution,
Alternatively, the bis-imide produced by dropping the reaction solution into a precipitant has a tar-like appearance because it has a high affinity with organic solvents. Therefore, when water is used as a precipitant, in order to enhance the dispersion effect of bis-imide in water and obtain good particulate precipitation, it is necessary to add alcohol to the homogeneous phase reaction solution after bis-imide formation. do. Examples of alcohols include methyl alcohol, ethyl alcohol, 1-propanol, 2-propanol, 1-butanol, 2-butanol, and t-butyl alcohol. The amount used is the reaction solution
In the range of 0.05 to 200g per 100g, preferably 1.0 to 200g
It is in the range of 50g. The amount of alcohol used is 0.05g
Below 200g, the bis-imide becomes tar-like.
Beyond this, the bis-imide becomes a colloid and is extremely difficult to handle. The reaction solution to which alcohols have been added can be made into fine particulate bis-containers by adding a precipitant or dropping it into a precipitant.
Give imide. The precipitants used are water,
Methyl alcohol, ethyl alcohol, 1-propanol, 2-propanol, 1-butanol,
Examples include compounds such as 2-butanol and t-butyl alcohol, which have low solubility in bis-imide and are compatible with the solvent of the reaction solution. Among these compounds, water or methyl alcohol are preferred precipitants in terms of ease of handling, low cost, and environmental hygiene. The amount of precipitant used depends on the amount of reaction liquid.
0.3 to 50 times the capacity is sufficient. The following operation is performed to purify the obtained bis-imide. That is, a basic compound such as sodium carbonate or sodium hydrogen carbonate is added to the slurry obtained by pouring the cake that is precipitated from the reaction solution and then separated from the mother liquor into water until the pH of the slurry is 8.0 or more.
Neutralize by adding to the range of 9.0, separate the cake, repeat washing with water moderately, thoroughly wash and purify with methyl alcohol, and then dry to obtain the target compound. In this case, it is not necessarily an essential condition to neutralize the slurry of the precipitate with a basic compound such as sodium carbonate, but the purification effect is sufficient if the precipitate is washed several times with water and then with alcohol. Demonstrated. However, if the slurry of the precipitate is neutralized with a basic compound, the target compound, bis-imide, can be further purified due to the synergistic effect. Alcohols used as cleaning agents in the method of the present invention include methyl alcohol, ethyl alcohol, 1-propanol, 2-propanol,
These are propanol, 1-butanol, and 2-butanol. The amount of alcohol used is 1.1 to 30 times the weight of the obtained precipitate. Washing with alcohol also has the advantage of shortening the drying process of the obtained bis-imide. It is a relatively high molecular weight compound containing two double bonds in the molecule, and when used alone or in combination with other suitable monomers or polymers, it undergoes a polymerization reaction and is a thermosetting resin mainly having a three-dimensional structure. Forms a cured product. The cured product obtained using this aromatic bis-imide has characteristics such as excellent heat resistance, dimensional stability, high toughness, and easy molding, and is used in the fields of electronics, electrical insulation materials, and mechanical parts. It is widely used in impregnated varnishes, laminates, paints, adhesives, molded products, etc. Furthermore, the bis-imide can be used as a pesticide,
It also has utility in fields that require unique functions, such as rubber medicine. The use of bis-imide takes advantage of the properties of this compound, such as easy solubility in organic solvents and low melting point, to simplify the work process and save energy. Hereinafter, the present invention will be specifically explained with reference to Examples. Example 1 9.4 g of maleic anhydride was dissolved in 64 ml of acetone,
Next, this solution was heated to bis[p,
p′-(α,α-dimethyl-p″-aminobenzyl)
26.8 g of phenoxyphenyl]sulfone was slowly added. After the addition was complete, stirring was continued for 2 hours at a temperature of 20°C. Next, 0.12 g of cobalt acetate tetrahydrate, 1.8 g of triethylamine, and 10.4 g of acetic anhydride were injected, the temperature of the reaction solution was raised, and stirring was continued at a temperature of 60° C. for 2.5 hours. Thereafter, the reaction solution was cooled to room temperature and gradually poured into 600 ml of thoroughly stirred water to obtain a precipitate.
Separate the precipitate, wash thoroughly with water, wash with methanol, and dry under reduced pressure at 55℃ to obtain a light brown powder.
32.2g (yield 97%) was obtained. The melting point of this compound is
The temperature was 125-132℃. Furthermore, according to infrared absorption spectra, 'H nuclear magnetic resonance absorption spectra, and elemental analysis values, this compound has the following structure: It was confirmed that it was Cyphenylsulfone. Infrared absorption spectrum As shown in Figure 1, a characteristic absorption of imidocarbonyl was observed at 1730 cm ^-1 . 'H nuclear magnetic resonance absorption spectrum (solvent DMSO-
D ₆ ) Chemical shift (δ value) is 1.68 ppm each -
CH ₃ , 7.12 ppm -CH of maleimide group, 7.00,
Resonance absorption attributed to -H of the benzene nucleus was observed at 7.30 and 7.92 ppm, and the absorption area intensity matched the proton number ratio. Elemental analysis value (%) C H N S Calculated value 72.45 4.86 3.38 3.87 Analysis value 72.29 4.80 3.31 3.94 Example 2 Bis[p,p′-(α,α-dimethyl-p″-aminobenzyl)phenoxyphenyl] sulfone
The same procedure as in Example 1 was carried out, except that 27.7 g of bis[p,p′-(α,α-dimethyl-p″-aminobenzyl)phenoxyphenyl]ketone was used instead of 26.8g.
32.0 g (yield 92.2%) of light brown powder was obtained. The melting point was 90-109°C. Infrared absorption spectrum is shown in Figure 2. 'H Nuclear Magnetic Resonance Absorption Spectrum Solvent DMSO-
D ₆ ) The chemical shifts (δ values) are 1.70ppm and -
CH ₃ , 7.12 ppm is -CH of maleimide group, 7.04,
Resonant absorptions attributable to -H of the benzene nucleus were observed at 7.30 and 7.76 ppm, and the absorption area intensity matched the proton number ratio. Elemental analysis value (%) C H N Calculated value 77.26 5.08 3.53 Analysis value 77.08 5.04 3.55 From the above analysis results, bis[p,p′-(α,α-dimethyl-p″-N-maleimide) having the structure of the following formula The formation of benzyl)phenoxyphenyl]ketone was confirmed. Example 3 The same procedure as Example 1 was carried out except that 15.7 g of 5-norbornene-2,3-dicarboxylic anhydride was used instead of 9.4 g of maleic anhydride, and 35.2 g of pale white powder (yield 92.8%) was obtained. Obtained. The melting point was 112-118°C (softer than 98°C). Infrared absorption spectrum is shown in Figure 3. 'H nuclear magnetic resonance absorption spectrum (solvent DMSO-
D ₆ ) Each chemical shift (δ value) could be attributed to the resonance absorption of each proton in the obtained chemistry, and the absorption area intensity matched the proton number ratio. From the above analysis results, the bis-
The production of najitsukuimide was confirmed.

[Brief explanation of the drawing]

Figures 1, 2 and 3 show the bis[p,p'-(α,α-dimethyl-p″-) obtained in Examples 1, 2 and 3.
N-maleimidobenzyl) phenoxyphenyl]
sulfone (Figure 1), bis[p,p'-(α,α-dimethyl-p″-N-maleimidobenzyl)phenoxyphenyl]ketone (Figure 2), and bis-nadizquimide (Figure 3) This shows the infrared absorption spectrum of .

Claims (1)

[Claims] 1 1) General formula (I) (In the formula, A represents -SO ₂ - or -CO-,
R′ and R″ are the same or different and represent a hydrogen atom, a halogen atom, or a lower alkyl group,
D represents [Formula] or [Formula], which may be different from each other. n' and n'' are integers from 1 to 4. When n' and n'' are 2 or more, each
(R′, R″ may be the same or different). 2) General formula () (In the formula, A represents -SO ₂ - or -CO-,
R′ and R″ are the same or different and represent a hydrogen atom, a halogen atom, or a lower alkyl group,
D represents [Formula] or [Formula] and may be different from each other. n' and n'' are integers from 1 to 4. When n' and n'' are 2 or more, each
(R′, R″ may be the same or different) is reacted with a dehydrating agent together with a catalyst and optionally a tertiary amine in the presence or absence of a solvent. General formula (I) (In the formula, A, D, R', R'', n' and n'' have the same meanings as in the general formula ()).