JPS6119633A - Synthesis of imide compound or its precursor - Google Patents

Abstract

PURPOSE:To obtain the titled inexpensive odorless compound which can give a molding which does not suffer deterioration of properties, by reacting an organic tetracarboxylic acid dianhydride with an organic diamine in a phenol novolak resin. CONSTITUTION:An organic tetracarboxylic acid dianhydride or its derivative is reacted with an organic diamine in a phenol novolak resin. Said novolak resin is one having a m.p. or a softening point of, usually, about 25-150 deg.C and being liquid, semisolid or solid at normal temperature. Examples of the organic tetracarboxylic acid dianhydrides include 3,3',4,4'-butanetetracarboxylic dianhydride and cyclopentanetetracarboxylic dianhydride. Examples of the organic diamines include 1,2-ethylenediamine and 4,4'-diaminodiphenyl ether.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a novel method for synthesizing an imide compound such as polyimide or its precursor using a phenolic novolac resin as a solvent during synthesis.

[Prior art]

Conventionally, polyimides have generally been produced by combining organic tetracarboxylic dianhydrides and organic diamines with dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methyl-
In basic polar solvents such as 2-pyrrolidone and hexamethylphosphoramide, or in organic polar solvents such as phenolic solvents such as m-cresol, p-cresol, phenol, m-chlorophenol, p-chlorophenol, and xylenol. Synthesize a polyimide precursor by reacting,
Furthermore, it was synthesized by heating this polyimide precursor to cause dehydration and ring closure.

In this conventional method for synthesizing BoIJ-(Mido), there were problems such as the above organic polar solvent used being expensive or having a strong odor even if it was cheap.Moreover, the above organic solvent When making a polyimide molded product, it must be completely removed, and if even a small amount remains, there is a problem that the properties of the polyimide molded product will be significantly impaired.

[Objective and Summary of the Invention] Therefore, the inventors used a solvent that is inexpensive, has no strong odor, and does not cause problems such as significant deterioration of the properties of the molded product even if it remains in the final molded product. As a result of intensive studies aimed at providing a method for synthesizing polyimide, it was discovered that a phenolic novolac resin can be a convenient solvent for achieving the above object, and the present invention was completed.

That is, the present invention relates to a method for synthesizing an imide compound or its precursor, which is characterized by reacting an organic tetracarboxylic dianhydride or its derivative with an organic diamine in a phenolic novolac resin.

[Effects of the Invention] According to the synthesis method of the present invention, since an inexpensive and odorless phenolic novolac resin is used as a solvent, imide-based compounds such as polyimide or their precursors can be synthesized at low cost and in a favorable working environment. can.

In addition, the phenolic novolac resin used as a solvent in this synthesis method is generally used as a curing agent for epoxy resins and various additives, and can also be made into cured molded products by using hexamethylene lenticule, thoramine, etc. as a curing agent. It is.

Therefore, even when the imide compound such as polyimide or its precursor obtained by the synthesis method of the present invention is separated from the phenolic novolac resin contained in the reaction product and used for various materials, Even if the resin is used with some residual resin, the properties of the resulting molded products will not be significantly impaired as in the past, and various additives and It has the advantage that it can be applied as a curing agent or as a molded product.This is an excellent feature that is significantly different from the conventional polyimide synthesis method, which required the removal of organic polar solvents. I can say that.

Further, the above-mentioned phenolic novolak resin has a melting point or softening point usually in the range of about 25 to 150°C, and is liquid, semi-solid or solid at room temperature. In the synthesis method of this invention, the phenolic 7-volatile resin in any of the above states may be used, unlike the organic polar solvents used in conventional polyimide synthesis methods, which are all liquid at room temperature. . That is, in the present invention, it is possible to selectively use a phenolic novolak resin that is semi-solid or solid at room temperature and carry out the synthesis reaction in a heated and melted state, and such a synthesis method has not been employed in the past. This method can be said to be unprecedented and unique to this invention.

[Structure of the invention]

The organic tetracarboxylic dianhydride used in the synthesis method of this invention is represented by the following general formula.

[However, R1 represents a tetravalent aliphatic residue or a tetravalent aromatic residue having at least two carbon atoms, and this aromatic residue is represented by one of the following structural formulas.

-C-0-1R3 is a divalent aromatic organic group having 6 to 30 carbon atoms, and R4 is a divalent organic group having 2 to 30 carbon atoms, such as -CH2CH2-1CH2CH (
OH) CH2-1CH2-c(CHJ2 CH2?, (
)] Specific examples of this organic tetracarboxylic dianhydride include:
For example, 3,3',4,4'-butanetetracarboxylic dianhydride, cyclo, pentanetetracarboxylic dianhydride,
5-(2,5-dioxotetrahydrofuryl)-3-methyl-3-cyclohexene-1,2-dicarboxylic anhydride, bicyclo[2.2.2]octe,
(7)-2,3,5,6-tetracarboxylic dianhydride, 0) Aliphatic tetracarboxylic dianhydride such as IO, pyromellitic dianhydride, 3,3,4,4' -Biphenyltetracarboxylic dianhydride, 2,3'-3',4'-biphenyltetracarboxylic dianhydride, 2,3,6,7-naphthalenetetracarboxylic dianhydride, 1,2,4, 5-naphthalenetetracarboxylic dianhydride, 1,2,5,6-naphthalenetetracarboxylic dianhydride, 3,3',4,4'-
Benzophenone tetracarboxylic dianhydride, 2,2-bis[4-(2,3-dicarboxyphenoxy)phenyl]propanihydride, 4,4'-his(2,3-dicarboxyphenoxy)diphenyl ether dianhydride These aromatic tetracarboxylic dianhydrides may be used alone or in a mixture of two or more thereof in the synthesis method of the present invention.

Further, examples of derivatives of organic tetracarboxylic dianhydrides used in the synthesis method of the present invention include tetracarboxylic oxides, lower alkyl esters, and polyhydric alcohol esters of the above-mentioned tetracarboxylic dianhydrides. It will be done.

Next, the organic diamine used in the synthesis method of the present invention is represented by the following general formula.

H2N -R5-NH2 [However, R5 represents a divalent aliphatic residue or a divalent aromatic residue having at least two carbon atoms, and this aromatic residue is, for example, one of the following structural formulas. It is expressed as

(However, Q is a monovalent aliphatic residue, an aromatic residue, or = C (
CR3)2) Furthermore, R3 may be a silicon-based material represented by the following structural formula.

(However, Q is as described above, R6 is a divalent aliphatic residue or aromatic residue, and m is a real number.) Specific examples of the above organic diamines include, for example, 1 as an aliphatic diamine.
・2-ethylenediamine, 1,6-hexamethylenediamine, xylylenediamine, inphorondiamine, p-
Cyclohexyldiamine, 3,9-bis(3-aminopropino b)-2,4,8,10-tetraoxaspiro-
[5.5]-Undecane etc. can be mentioned.

Examples of aromatic diamines include 4,4'-diaminodiphenyl ether, 3,3-dimethyl-4,4'-diaminodiphenyl ether, 3,3'-dimethoxy-4
・Diphenyl ether-based cyamines such as 4-diaminodiphenyl ether, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4
'-Diamino diphenyl thioether, 3,3-dimethyl-4,4'-diaminodiphemol thioether, 3.
Diphenylthioethers such as 3'-dimethoxy-4,4'-diaminosif'I nylthioether and 3,3-diaminodiphenylthioether.

゛ Diamine, 4,4-diaminobenzophenone, 3
・3-dimethyl-4,4'-diaminobenzophenone,
Benzophenone diamines such as 3,3'-diaminobenzophenone, 3,3-diaminodiphenylmethane, 4
・Diphenylmethane diamines such as 4'-diaminodiphenylmethane, 3,3-dimethoxy-4,4-diaminodiphenylmethane, 3,3-dimethyl-4,4-diaminodiphenylmethane, 2,2-bis(4-aminophenyl)propane , 2,2-bis(3-aminophenyl)
Bisphenylpropane diamines such as propane, 4.
Diphenylsulfoxide diamines such as 4-diaminodiphenylsulfoxide and 3,3'-diaminodiphenylsulfoxide, diphenylsulfone diamines such as 4,4-diaminodiphenylsulfone and 3,3-diaminodiphenylsulfone, benzidine, 3,3'- Dimethylbenzidine, 3.3'-dimethoxybenzidine, 3.
Biphenyl diamines such as 3'-diaminobiphenyl, pyridine diamines such as 2,6-diaminopyridine, 3,6-diaminopyridine, 2,5-diaminopyridine, 3,4-diaminopyridine, o-lm- or p −
Diaminobenzene, 3,5-diaminobenzoic acid, etc., 4
・Idi(m-aminophenoxy)diphenylsulfone, 4,4'-di(p-aminophenoxy)diphenylsulfone, 4,4'-di(m-aminophenoxy)diphenyl ether, 4,4'-di(p- aminophenoxy)
Diphenyl ether, 4,4'-di(m-aminophenoxy)diphenylpropane, 4,4'-di(p-aminophenoxy)diphenylpropane, 4,4'-di(m-
aminophenylsulfonyl) diphenyl ether, 4.
4'-di(p-aminophenylsulfonyl) diphenyl ether, 4,4'-diCm-aminophenylthioether) diphenyl sulfide, 4,4'-di(p-aminophenylthioether) diphenyl sulfide, 4,4' -di(m-aminophenoxy)diphenylketone, 4,d-di(p-aminophenoxy)diphenylketone, 4,4'-di(m-aminophenoxy)diphenylmethane, 4,4'-di(,p-amino Examples include phenoxy)diphenylmethane.

In addition, as a silicon-based diamine, for example, the following formula
Examples include those expressed in .

H3CH3 C6H6C6H5 H3CH3 In the synthesis method of this invention, one of the above organic diamines is used.
A species may be used alone or a mixture of two or more species may be used.

The phenolic novolak resin used in the synthesis method of the present invention includes phenolic compounds such as phenol, cresol, xylenol, resorcinol, chlorophenol, phenylphenol, saligenin, bisphenol A1 bisphenol AF, catechol, and hydroquinone, formaldehyde, para It is a condensate obtained by reacting formaldehyde and other aldehydes under an acid catalyst.

This phenolic novolac resin has a number average molecular weight [gel permeation chromatography (C,
, P, C(1)] is usually about 250 to 5,000, and the melting point or softening point is usually in the range of 25 to 150°C. That is, the above-mentioned resin may be in a liquid, semi-solid or solid state at room temperature.

In the synthesis method of the present invention, the above-mentioned organic tetracarboxylic dianhydride, its derivative, or a mixture of the two is reacted with the above-mentioned organic diamine in the above-mentioned phenolic novolac resin to produce an imide-based compound such as polyimide or a polyamic acid. Synthesize imide compound precursors such as

The ratio of the above-mentioned organic tetracarboxylic dianhydride or its derivative to organic diamine is determined depending on the type of target compound, but the molar ratio is usually 1:2 to 2:1.
It is better to set it as a degree.

The reaction temperature and reaction time in the above reaction are set depending on the type of target compound, and when synthesizing a precursor of a polyimide compound such as polyamic acid, it is usually
1 to 20 hours below °C, more typically 40 to 6
It is sufficient to react at 0°C for about 1 to 5 hours, and in order to synthesize imide compounds such as polyimide, the reaction is usually carried out at a temperature exceeding 80°C for about 1 to 20 hours, more generally at 150°C.
The reaction may be carried out at ~250°C for about 1 to 5 hours. In addition, by adjusting the reaction temperature and reaction time, it is possible to synthesize an imide compound precursor such as polyamic acid and then proceed with the reaction to partially imidize it, or to form an imide compound such as polyimide. .

The phenolic novolak resin used as a solvent in the above reaction is selected from one that becomes molten at the above reaction temperature, and has a melting point or softening point of 35 to 150.
A semi-solid or solid phenolic novolak resin at a temperature of 0.degree. C. is used when the reaction temperature is above this melting point. The melting point or softening point, including liquid ones, is usually 80.
Phenolic novolak resins with temperatures below ℃ are generally used as solvents in the synthesis of imide compounds and their precursors, but when their melting point or softening point is usually above 80℃, they are generally used as solvents in the synthesis of imide compounds. used.

The amount of this phenolic novola resin used is:
Generally, the total amount of the organic tetracarboxylic dianhydride or its derivative and the organic diamine is preferably about 1' to 200 parts by weight based on 100 parts by weight of the resin.

In the synthesis method of the present invention, the above-mentioned components may be simultaneously charged into a reaction vessel and then reacted at a predetermined temperature and time, or the phenolic novolak resin may be first heated to a molten state, and then the resin may be heated. The reaction may be carried out at a predetermined temperature and time after adding organic tetrakatL dianhydride or its derivative and organic diamine simultaneously or sequentially, and the order of addition of each of the above components is not particularly limited. .

Furthermore, in this synthesis method, a tertiary amine may be used as a catalyst for the above reaction, if necessary. Specific examples of this tertiary amine include pyridine, 2-chloropyridine, 2,4,6-collidine, 2,6-dichloropyridine, α,β,'r-picoline, 4-phenylpropylpyridine, 2- Propylpyridine, 2,6-lutidine, 2.
Pyridines such as 4-lutidine, 2,5-lutidine, 3,4-lutidine, aliphatic tertiary amines such as triethylamine, trimethylamine, N-N-dimethyldodecylamine, triethylenediamine, tri-n-butylamine, 1 -Benzyl-2-methylimidazole, 1-cyanoethyl-2-methylimidazole, 1-cyanoethyl-2-phenylimidazole, 1-cyanoethyl-2
- Imidazoles with or without active hydrogen such as ethyl-4-methylimidazole and 1-cyanoethyl-2-lydecylimidazole, aromatic systems such as N-N-dimethyl-p-toluidine and N-N-dimethylbenzylamine Tertiary amines, 1,8-diazabicyclo(5.4.0)
Examples include undecene-7 and its acid form.

Furthermore, even if the organic tricarboxylic acid anhydride or its derivative or the organic dicarboxylic acid anhydride or its derivative is contained in the organic tetracarboxylic dianhydride or its derivative in the above-mentioned organic tricarboxylic acid anhydride or its derivative, it is usually less than mol% of the total amount. Often, the dicarboxylic acid anhydride or its derivative is
It can function as a reaction terminator when organic tetracarboxylic dianhydride or its derivative and organic diamine are reacted at a molar ratio of 1:1.

Note that when an imide compound is synthesized by the above reaction, since water is produced as a by-product, it is preferable to proceed with the reaction while removing this water. In addition, in the above reaction, the synthesized imide compound precursor such as polyamic acid is generally dissolved in the phenolic novolak resin melted at the reaction temperature, but the imide compound such as polyimide varies depending on its type and molecular weight. It may be dissolved in the phenolic novolak resin melted at the reaction temperature, or it may be dispersed without being dissolved.

By changing the name of the synthesis method of the present invention, the type and ratio of the organic tetracarboxylic dianhydride or its derivative used and the organic diamine, or the reaction temperature and reaction time, various imide compounds or their derivatives can be synthesized. A precursor can be obtained.

For example, when reacting an organic tetracarboxylic dianhydride and an organic diamine at a temperature exceeding 80°C for about 1 to 20 hours, the proportion of the same component used is If it is 2 moles, then
An imide compound represented by the general formula is obtained using a conventional method.

(However, R1 and R5 are as described above.) In addition, under the above reaction conditions, if the ratio of the same components used is 1 mole of organic diamine to 2 moles of organic tetracarboxylic dianhydride, then Imide compounds represented by the general formula and their acid-terminated compounds are obtained.

(However, RI and R1 are as described above.) In addition, if the ratio of the same components used is 1 mole of organic diamine to 1 mole of organic tetracarboxylic dianhydride under the above reaction conditions, then A polyimide represented by the general formula is obtained.

(However, as mentioned above, for R□ and R5, n is a real number.) If the proportion of the same component used is other than the above, then for example, an organic diamine may be used more generously depending on the proportion. When a large amount of dianhydride is used, an imide compound having a terminal amide group can be obtained.

Organic tetracarboxylic dianhydride and organic diamine in 1:
When reacting at a molar ratio of 1 or close to this, polyimide may be obtained as described above, or a polyimide precursor or a partially imidized polyimide precursor may be obtained depending on the reaction temperature and reaction time. However, if the compound obtained by these syntheses is soluble in N-methyl-2-pyrrolidone, it can be prepared at 30°C at a concentration of 0.5y7100me in N-methyl-2-pyrrolidone.
When the logarithmic viscosity measured in sulfuric acid is usually about 0.1 to 2.0, and the above compound is polyimide and is insoluble in N-methyl-2-pyrrolidone, O-5y7100me in sulfuric acid is The logarithmic viscosity measured at 30° C. is usually about 0.1 to 1.6.

The imide compound or its precursor obtained by the synthesis method of the present invention can be separated from the phenolic novolak resin using a solvent such as acetone that does not dissolve these compounds but can dissolve the phenolic novolak resin. but,
Even if the mixture with the phenolic novolak resin is not subjected to such separation, it can be used for various purposes.

Examples of this application include, for example, when the above mixture is used as a curing agent for epoxy resin, the heat resistance of the epoxy resin can be improved, and when the imide compound or its precursor in this mixture is a high molecular weight substance, can make the epoxy resin low stress. The above mixture can also be used as a molding material with good heat resistance using hexamethylenetetramine as a curing agent. In addition, the above mixture is used in various fields such as adhesives, molded product foams, sealing resins for LSIs, fiber reinforced composites such as fiber reinforced plastics, laminates and prepreg products, and epoxy resins and phenolic resins for printed circuit boards. It can be applied.

In addition, when the reactant obtained by the synthesis method of the present invention is separated from the phenolic novolak resin by the above-mentioned means and used, it is possible that the reactant is an imide precursor or a precursor partially containing imide. In some cases, if necessary, this reaction product may be heat-treated at a high temperature after the above-mentioned separation to obtain a completely imidized imide compound for use.

〔Example〕

Examples of this invention will be described below. In addition, in the following, the logarithmic viscosity in N-methyl-2-pyrrolidone (hereinafter referred to as NMP) is 0.5 in NMP.
Logarithmic viscosity in sulfuric acid means the logarithmic viscosity measured at 30°C at a concentration of fj/100me, and logarithmic viscosity in sulfuric acid at 30°C at a concentration of 0.59/100rne in sulfuric acid.
means the logarithmic viscosity measured at Further, the IR spectrum (infrared absorption spectrum) was measured by the KBr method.

Furthermore, the term % hereinafter means % by weight.

Example 1 Phenol novolak resin, which is a condensation product of phenol and formaldehyde (softening point 78-86°C, 150°C by Ubbelohde viscometer), was placed in a 500me separable flask.
Add 300y (viscosity 1.8~3.4voices at °C),'
``While flowing nitrogen gas, the material was melted by heating and the temperature was raised to 180°C.

Next, while stirring the inside of the flask, 14.884;' (0.06 mol) of 3,3'-diaminodiphenylsulfone was added and completely dissolved, and then 2,3,3'
・4'-biphenyltetracarboxylic dianhydride 17.6
Gradually add 4y (006 mol) and then heat to 180°C.
The mixture was allowed to react for 4 hours. Note that water began to distill out of the system about 20 minutes after the above addition.

After the above reaction, the phenol novolac resin was poured into a flat vat while in a molten state and cooled.

The resulting reaction mixture was a brown transparent resin.

This reaction mixture was dissolved in NMP, acetone was added thereto, and the mixture was separated into an acetone-soluble component and an acetone-insoluble component. This acetone-insoluble matter was dried under reduced pressure at 80°C for 4 hours to obtain a powder. The logarithmic viscosity of this powder in NMP was 0.31. In addition, the IR spectrum of this powder (Figure 1) shows the characteristic absorption of imide groups at 1780σ and 1650cm
Characteristic absorption of T mido group was observed in , and the yield was 998.
%Met.

Next, the above powder was heat treated at 250° C. for 4 hours, and then its CNMR spectrum was examined, and the results are shown in FIG. Since this spectrum and the CNMR spectrum of polyimide obtained by the conventional method shown in FIG. I can clearly see something.

, The above 13CNMR spectrum is from JEOL (@(
The measurement was carried out using DMSO (dimethyl sulfoxide) d6 as a solvent using an FX-60 model NMR apparatus manufactured by JEOL LTD. Moreover, the polyimide obtained by the conventional method shown in FIG. 4 was synthesized as follows.

That is, 3,3-diaminodiphenylsulfone and 2.
A polyimide precursor was synthesized by reacting equimolar amounts of 3,3',4'-biphenyltetracarboxylic dianhydride in NMP at 30°C or less for 240 minutes, and this was reprecipitated in water-acetone. A polyimide precursor powder was obtained. This powder was heated at 180'C for 1 hour and then at 250°C for 4 hours to obtain a polyimide powder. This polyimide precursor was soluble in NMP and had a logarithmic viscosity of 1.1 in NMP. In addition, the IR spectrum (Figure 2) of this powder shows 1
Characteristic absorption of imide groups was observed in 780c1n.

Example 2 A reaction was carried out in the same manner as in Example 1 except that the reaction conditions were 130° C. for 3 hours to obtain a brown transparent resin-like reaction mixture. This reaction mixture was pulverized, and acetone was added to separate it into an acetone-soluble component and an acetone-insoluble component. This acetone-insoluble matter was dried under reduced pressure at 80°C for 4 hours to obtain a yield of 62.3.
% powder was obtained.

This powder was soluble in NMP and had a logarithmic viscosity of 0.27 in NMP. Furthermore, in the IR spectrum of this powder (Figure 5), a characteristic absorption of the imide group is observed at 1780 cm and a characteristic absorption of the amide group is observed at 1650 cm. The imidization rate is about 7 based on the strength.
It was 4%.

The 'HNMR spectrum of this powder (Figure %S6) and the 'HNMR spectrum of the partially imidized polyamic acid obtained by the conventional method (Figure 7) were almost the same. From this, it is clear that the powder is made of partially imidized polyamic acid.

The above 'HNMR spectrum was measured using the same NMR apparatus as above. Further, the partially imidized polyamic acid according to the conventional method shown in FIG. 7 was synthesized as follows.

That is, needle hoko diaminodiphenylsulfone and 2.3.
Reacting equimolar amounts of 3', 4'-biphenyltetracarboxylic dianhydride in NMP at 30°C or lower for 240 minutes,
This reaction product was reprecipitated in water-acetone, and the thus obtained powder was dried under reduced pressure at 80° C. for 24 hours to obtain partially imidized polyamide and doric acid.

Example 3 Phenol novolac resin (same as Example 1) 30
0y, 4,4'-diaminodiphenylmethane 11.88
y (0.06 mol) and pyromellitic dianhydride 13
．． A reaction was carried out in the same manner as in Example 1 using 0.08y (0.06 mol). However, the reaction conditions were 180° C. for 3 hours. This reaction gave a pale yellow, opaque, resinous reaction mixture.

This reaction mixture was pulverized, and in the same manner as in Example 2, the acetone-insoluble matter was separated and dried under reduced pressure to obtain a powder. This powder was insoluble in NMP and had a logarithmic viscosity of 0.37 in sulfuric acid. In addition, the IR spectrum (Figure 8) of this powder shows 1
A characteristic absorption of the imide group was observed at 780 cm-', and 16
At 50 cm, almost no characteristic absorption of amide groups was observed. That is, this powder consisted of almost completely imidized polyimide, and the yield was 992%.

Examples 4-9 Phenol novolac resin (same as Example 1) 30
A reaction was carried out in the same manner as in Example 1 using 0.06 mol each of Oy, an organic tetracarboxylic dianhydride, and an organic diamine shown in the table below.

However, the reaction conditions were 180° C. for 3 hours. Through this reaction, transparent resin-like reaction mixtures were obtained in Examples 4, 5, and 8.9, and opaque resin-like reaction mixtures were obtained in Examples 6 and 7.

Acetone-insoluble components were separated from each of the above reaction mixtures in the same manner as in Example 2 and dried under reduced pressure to obtain powder. If the powder obtained is soluble in NMP, the logarithmic viscosity in NMP is measured, and if the powder is insoluble in NMP, the logarithmic viscosity is measured in sulfuric acid, and these results are shown in the table below. Indicated.

Further: When the IR spectra of the above powders were measured, characteristic absorption of imide groups was observed at 1780cIn in all powders, and no characteristic absorption of amide groups was observed at 1650-. Accordingly, all of the above powders were identified as polyimide, and the yields thereof were as shown in the table below.

In addition, in the table above, ci-BPDA refers to 2, 3,
3'/4'-biphenyltetracarboxylic dianhydride, B
TDA means 3,3',4,4'-benzophenonetetracarboxylic dianhydride, PMDA means pyromellitic dianhydride, DAM means 4,4'-diaminodiphenylmethane, 3. 3'-DDS means 3.
3-diaminodiphenylsulfone, 4,4'-BAPP
2,2'-bis(4-aminephenoxyphenyl)propane, 4,4'B A P S means 4
・4'-di(4-aminophenoxy)diphenylsulfone and DDE mean 4,4'-diaminodiphenyl ether, respectively.

Example 10 A phenolic novolak resin (softening point 92-102°C, Ubbelohde viscometer) obtained by condensation reaction with toformaldehyde of a mixture of m-cresol and phenol in a molar ratio of 1:1 was placed in a 500 me separable flask. (viscosity at 150°C: 1 to 3 poise) was put therein and heated to melt while flowing nitrogen gas, and the temperature was raised to 180°C.

Next, add 4.4' to this flask while stirring.
- Add 8.32y (0,042 mol) of diaminodiphenylmethane and dissolve completely, then 3.3'.4
・4'-benzophenone tetracarboxylic dianhydride 19
．． Gradually add 32y (0,06 mol), then 18
The reaction was carried out at 0°C for 4 hours. Note that after the above addition, 20 to 30
After a few minutes had passed, water began to distill out of the system.

After the above reaction, the phenolic novolak resin was poured out in a molten state into a flat vat and cooled.

The resulting reaction mixture was a brown transparent resinous substance.

Acetone-insoluble matter was separated from this reaction mixture in the same manner as in Example 2 and dried under reduced pressure to obtain polyimide powder with a yield of 97.8%. This powder was insoluble in NMP and had a logarithmic viscosity in sulfuric acid of 0.12. In addition, I of the above reaction mixture
In the R spectrum (Figure 9), a characteristic absorption of isdo group was observed at 1780c+++, and almost no characteristic absorption of amide group was observed at 165-.

Example 11 The amount of 4,4'-diaminodiphenylmethane used was 118
82 (006 mol) and the amount of 3,3',4,4'-benzophenonetetracarboxylic dianhydride used is 13°5:
The reaction was carried out in the same manner as in Example 10 except that the amount of the reaction mixture was changed to 1 (0,042 mol) to obtain a reaction mixture in the form of a brown transparent resin.

Acetone-insoluble matter was separated from this reaction mixture in the same manner as in Example 2 and dried under reduced pressure to obtain polyimide powder with a yield of 98.2%. This powder was insoluble in NMP and had a logarithmic viscosity in sulfuric acid of 0.09.

The IR spectrum of this reaction mixture (Figure 10) shows 17
Characteristic absorption of Ikudo group was observed at 80c+n, and 16
No characteristic absorption of the ado group was observed in 50■.

Example 12 Phenol novolak resin (same as Example 1) 30
Example 1 using 0y, 2,4-tolylene diamine 732y (0,06 mol) and 3,3′,4,4′-benzophenonetetracarboxylic dianhydride 9.66y (0,03 mol) The reaction was carried out in the same manner.

The reaction conditions were 180'C for 4 hours. This reaction gave a brown transparent resinous reaction mixture.

Acetone-insoluble matter was separated from this reaction mixture in the same manner as in Example 2 and dried under reduced pressure to obtain imide powder with a yield of 98.6%. This powder was soluble in NMP and had a logarithmic viscosity of 0.02 in NMP. Further, the weight average molecular weight of this powder was measured by the G, P, C method and was found to be 530. Further, in the IR spectrum of this powder (Fig. 11), a characteristic absorption of imide groups was observed at 1780c+++, and no characteristic absorption of amide groups was observed at 1650σ.

Example 13 Phenol novolak resin (same as Example 1) 30
0y, xylylenediamine 4.08P (0.03 mol)
A reaction was carried out in the same manner as in Example 1 using 17.64y (0.06 mol) of 2,3,3',4'-biphenyltetracarboxylic dianhydride. Reaction conditions are 180℃
So it was 4 hours. This reaction gave a light brown transparent resinous reaction mixture.

Acetone-insoluble matter was separated from this reaction mixture in the same manner as in Example 2 and dried under reduced pressure to obtain imide powder with a yield of 978%. This powder was soluble in NMP and had a logarithmic viscosity of 0.08 in NMP. Further, the weight average molecular weight of this powder was measured by the G, P, C method and was found to be 704. In addition, the IR spectrum (Figure 12) of this powder shows 1
Characteristic absorption of imide group was observed at 780σ, and 1650c
No characteristic absorption of the amide group was observed in 1n.

[Brief explanation of the drawing]

Figures 1, 5, 8, 9, 10, 1L, and 12 show infrared absorption spectra of imide compounds or their precursors obtained by the method of the present invention, respectively. Figure 2 is a characteristic diagram showing the infrared absorption spectrum of polyimide obtained by the conventional method, and Figure 3 is a characteristic diagram showing the infrared absorption spectrum of the polyimide obtained by the method of the present invention.
FIG. 4 is a characteristic diagram showing the CNMR spectrum of polyimide obtained by the conventional method. FIG. 6 is a characteristic diagram showing the CNMR spectrum of the polyimide obtained by the method of the present invention. FIG. 7 is a characteristic diagram showing the 1HN-MR spectrum of a partially imidized polyamic acid obtained by a conventional method. Patent applicant: Nitto Electric Industry Co., Ltd. FIG. 1 Figure 2 Figure 3 Quest 4 Figure 1 & 1 160 %OPPM 120
M Figure 5 Figure 8 456 Figure 7 1211109 8 7 6 , M 99 *Sioz

Claims (2)

[Claims] (1) A method for synthesizing an imide compound or its precursor, which comprises reacting an organic tetracarboxylic dianhydride or its derivative with an organic diamine in a phenolic novolac resin. (2) The phenolic novolak resin has a melting point or softening point of 35 to 150°C and is semi-solid or solid at room temperature, and the organic tetracarboxylic dianhydride or its derivative and the organic diamine are combined with the above phenolic novolac resin. The method for synthesizing an imide-based compound or its precursor according to claim (1), wherein the reaction is carried out at a temperature higher than the melting point or the softening point of the resin.