JP2999114B2 - Heat-resistant polyimide and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a process for producing a polyimide having good processability.

[0002]

2. Description of the Related Art Conventionally, polyimides obtained by the reaction of a tetracarboxylic acid and a diamine have various excellent physical properties and good heat resistance, so that they will be used in the fields of electronics, the aerospace industry, etc. Is expected.

Conventionally developed polyimides often have excellent properties, but have excellent heat resistance but poor workability, and resins developed for the purpose of improving workability have poor heat resistance. There were advantages and disadvantages in performance. For example, equation (7)

[0004]

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A polyimide having a basic skeleton represented by the following formula (manufactured by DuPont, trade name: Kapton, Vespel) is a polyimide having no clear glass transition temperature and excellent heat resistance, but is used as a molding material. In such cases, processing is difficult, and processing must be performed using a special method such as powder sintering. In addition, when used as a material for electrical and electronic components, it has a property of having a high water absorption that adversely affects dimensional stability, insulation properties, and solder heat resistance. Equation (8)

[0006]

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A polyetherimide having a basic skeleton represented by the following formula (trade name, manufactured by General Electric Co., Ltd.)
Ultem) is a resin with excellent processability, but has a low glass transition temperature of 217 ° C, is soluble in halogenated hydrocarbons such as methylene chloride, and is satisfactory in terms of heat resistance and solvent resistance. is not. As a result of intensive studies to solve these disadvantages, we found that the general formula (9)

[0008]

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(Wherein X, Y _{1 to} Y ₄ , and R are the same as those described above) and have already filed an application. (Japanese Unexamined Patent Publication No. 1-110530)

The polyimide resin has a temperature of 170 ° C. to 270 ° C.
Shows a clear glass transition temperature in the range, almost no reduction in weight even at around 400 ° C., and good workability. In addition, it has excellent chemical resistance and compensates for the disadvantages of conventional polyimides.

There are various methods for synthesizing the polyimide resin.
A method is known in which a raw material, tetracarboxylic dianhydride, is reacted with a diamine to obtain a polyamic acid, and then subjected to dehydration cyclization by heat or a method of obtaining a polyimide by dehydration cyclization with acetic anhydride. However, such a polyimide resin also has problems such that the processability becomes poorer as the molecular weight increases, the resin gels during processing, and the viscosity of the resin increases. In order to solve the above problem, the present inventors have heretofore carried out the addition of a dicarboxylic anhydride to both ends of a diamine, and further a dehydration cyclization of the general formula (10)

[0012]

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(Wherein X, Y _{1 to} Y ₄ , and R are the same as described above), and that the processability is improved by adding the bisimide compound to the polyimide resin. Application already filed (Japanese Patent Application No. 03
-004963, Japanese Patent Application No. 03-086558). Also,
The inventors of the present invention synthesize the polyimide by synthesizing the above diamine and tetracarboxylic dianhydride in a specific molar ratio to obtain a compound represented by the general formula (9).

[0014]

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(Wherein X, Y _{1 to} Y ₄ and R are the same as described above), and a processability is obtained by adding the polyimide oligomer to the polyimide resin. And have already filed applications (Japanese Patent Application Nos. 04-340138 and 04-342548).

Further, the present inventors have found that by synthesizing a polyimide under a specific reaction condition, a polyimide resin containing a low molecular weight polyimide oligomer and having good processability can be obtained in one pot, and has already filed an application ( Japanese Patent Application No. 05-276387). As described above, the workability is improved by the presence of a low molecular weight component such as a bisimide compound or a polyimide oligomer in the polyimide resin, but there is a problem even in such a case.

[0017]

Generally, a polyimide resin containing a large amount of low molecular weight components such as a bisimide compound and a polyimide oligomer has good workability in extrusion molding and the like, but contains a large amount of low molecular weight components. The polymer does not reach the critical molecular weight, and the glass transition temperature and melting point of molded products obtained by injection molding etc. decrease,
The heat distortion temperature may be low. Further, the fatigue resistance is not sufficient. In order to solve this problem, it is only necessary to increase the molecular weight or to produce a polymer having a low molecular weight component, but if the molecular weight is high, the processability becomes poor, and it becomes difficult to obtain a molded product by melt molding. . Polyimide containing a large amount of low molecular weight components has advantages and disadvantages such as the occurrence of such problems in physical properties after molding.

As a polymer for improving heat resistance, there has been known a heat-resistant polymer having a benzimidazole ring or an imidazopyrrolo ring alone in a polymer main chain. For example, JP-B-44-23112 describes a heat-resistant polymer containing a imide bond and a ladder structure in the skeleton by reacting a precursor obtained by reacting tetramine and an acid anhydride with triamine.

Japanese Patent Application Laid-Open No. 5-254064 describes that a polyimide precursor is modified by adding triamine or tetramine. However, the polymers obtained by these methods are all thermosetting, cannot be melt-molded after they have reacted to form polyimide, and their uses are very limited.

Thus, a polyimide resin which can be melt-molded, exhibits good processability in extrusion molding and injection molding, and does not impair heat resistance and fatigue resistance of a molded product and a method for producing the same have been desired. .

[0021]

The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, introduced a specific third component into the polyimide resin at a specific ratio, thereby obtaining a skeleton. By using a part of the ladder structure, it was found that not only polyimide resin synthesized by the conventional method has better moldability such as extrusion molding, but also a polyimide resin that does not impair heat resistance can be obtained. Thus, the present invention has been completed. That is, the present invention provides the following formula (1)

[0022]

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(Wherein, X is a group consisting of a direct bond, a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group, a sulfonyl group or an oxide. Represents a selected group, Y ₁ ,
Y ₂ , Y ₃ and Y ₄ each independently represent a group selected from the group consisting of hydrogen, lower alkyl group, lower alkoxy group, chlorine and bromine, and may be the same or different. R is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, a non-condensed cyclic group in which aromatic groups are connected to each other directly or by a bridge member. A tetravalent group selected from the group consisting of aromatic groups; W represents a tetravalent group having at least 4 carbon atoms; a bond between (a) and (b), and (c) and ( The bond d) is a polyimide resin represented by a repeating unit of the formula (2) wherein W is bonded to carbon atoms adjacent to each other.

[0024]

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The polyimide resin is one or a mixture of two or more selected from the group consisting of a polyimide resin and a diamine represented by the following formula (3):

[0026]

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(Wherein X is a group consisting of a direct bond, a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group, a sulfonyl group or an oxide. Represents a selected group, Y ₁ ,
Y ₂ , Y ₃ and Y ₄ each independently represent a group selected from the group consisting of hydrogen, lower alkyl group, lower alkoxy group, chlorine and bromine. ) Is a diamine compound represented by the following formula (4):

[0028]

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(In the formula, R represents an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, or an aromatic group, either directly or by a crosslinking member. A tetravalent dianhydride selected from the group consisting of linked non-condensed cyclic aromatic groups.) And further represented by the following formula (5)

[0030]

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(Wherein W represents a tetravalent group having at least 4 carbon atoms, and the bond between (a) and (b) and the bond between (c) and (d) are carbon atoms adjacent to each other. The reaction is carried out in the presence of tetramine represented by the following formula (6):

[0032]

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(Wherein Z is a group consisting of a monocyclic aromatic group, a condensed polycyclic aromatic group, and a non-condensed polycyclic aromatic group in which the aromatic groups are connected to each other directly or by a bridging member. The reaction is carried out in the presence of a dicarboxylic anhydride represented by the following formula: and the amount of tetracarboxylic dianhydride is 0.90 to 0.90 per mole of the total of diamine and tetramine.
0.99 mole ratio, and the amount of tetramine is 0.001 to 0.3 mole ratio with respect to 1 mole of the total of diamine and tetramine, and 1 mole of the total amount of diamine and tetramine, and Formula (1) wherein the total amount of anhydride and dicarboxylic anhydride is 1.0 to 2.0 in equivalent ratio

[0034]

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(Wherein X, Y _{1 to} Y ₄ , W and R are the same as those described above). This is a method for producing a polyimide resin having a repeating unit represented by the following formula: '-Diaminobenzidine, 1,2,4
5-tetraaminobenzene, 3,3 ', 4,4'-tetraaminophenyl ether, 3,3', 4,4'-tetraaminophenylsulfone, 3,3 ', 4,4'-tetraaminophenylketone Or a mixture of two or more selected from the group consisting of polyimide resins.

Hereinafter, the present invention will be described in detail. When the polyimide resin obtained in the present invention is obtained by reacting a specific diamine compound with tetracarboxylic dianhydride to obtain a polyimide resin, a specific tetramine is added and reacted to form a polyimide resin having a one-dimensional structure. It is characterized by having a partial ladder structure.

Although the polyimide resin obtained by the present invention has a workability equivalent to that of a conventional polyimide resin having an equivalent molecular weight, a part of the polyimide resin has a ladder structure having excellent heat resistance, and thus the glass has a glass composition. The transition temperature, melting point, and heat deformation temperature are increased, and the heat resistance and fatigue resistance are improved.

The diamine used in the present invention includes bis [4- (3-aminophenoxy) phenyl] methane,
1,1-bis [4- (3-aminophenoxy) phenyl] ethane, 1,2- [4- (3-aminophenoxy)
Phenyl] ethane, 2,2-bis [4- (3-aminophenoxy) phenyl] propane, 2,2-bis [4-
(3-aminophenoxy) phenyl] butane, 2,2-
Bis [4- (3-aminophenoxy) phenyl] -1,
1,1,3,3,3-hexafluoropropane, 4,
4'-bis (3-aminophenoxy) biphenyl, bis [4- (3-aminophenoxy) phenyl] ketone, bis [4- (3-aminophenoxy) phenyl] sulfide, bis [4- (3-aminophenoxy) Phenyl] sulfoxide, bis [4- (3-aminophenoxy) phenyl] sulfone, bis [4- (3-aminophenoxy)
Phenyl] ether and the like, and these are used alone or in combination of two or more.

Examples of the tetracarboxylic dianhydride include ethylene tetracarboxylic dianhydride, cyclopentanecarboxylic dianhydride, pyromellitic dianhydride, 3,3 ′, 4
4'-benzophenonetetracarboxylic dianhydride, 2,
2 ', 3,3'-benzophenonetetracarboxylic dianhydride, 3,3', 4,4'-biphenyltetracarboxylic dianhydride, 2,2 ', 3,3'-biphenyltetracarboxylic dianhydride 2,2′-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2′-bis (2,3-dicarboxyphenyl) propane dianhydride,
Bis (3,4-dicarboxyphenyl) ether dianhydride, bis (3,4-dicarboxyphenyl) sulfone dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (2,3-dicarboxyphenyl) methane dianhydride, 1,1-bis (2,3-dicarboxyphenyl) ethane dianhydride, bis (3,4-dicarboxyphenyl) methane dianhydride, 2, 3,6,7-
Naphthalenetetracarboxylic dianhydride, 1,4,5,8
-Naphthalenetetracarboxylic dianhydride, 1,2,5
6-naphthalenetetracarboxylic dianhydride, 1,2,2
3,4-benzenetetracarboxylic dianhydride, 3,4
9,10-berylenetetracarboxylic dianhydride, 2,
3,6,7-anthracenecarboxylic dianhydride, 1,
Examples thereof include 2,7,8-phenanthrene carboxylic dianhydride and the like, which are used alone or in combination of two or more.

Examples of tetramine include 3,3'-diaminobenzidine, 1,2,4,5-tetraaminobenzene,
3,3 ′, 4,4′-tetraaminophenyl ether,
3,3 ′, 4,4′-tetraaminophenylsulfone,
3,3 ', 4,4'-tetraaminophenylketone and the like can be mentioned, and these can be used alone or as a mixture of two or more.

The dicarboxylic anhydride represented by the general formula (4) used as a terminal blocking agent in the present invention includes phthalic anhydride, 2,3-benzophenone dicarboxylic anhydride, and 3,4-benzophenone dicarboxylic acid. Anhydride, 2,
3-dicarboxyphenyl-phenyl-ether anhydride, 3,4-dicarboxyphenyl-phenyl-ether anhydride, 3,4-biphenyldicarboxylic anhydride,
2,3-dicarboxyphenyl-phenyl-sulfone anhydride, 2,3-dicarboxyphenyl-phenyl-sulfide anhydride, 1,2-naphthalenedicarboxylic anhydride, 2,3-naphthalenedicarboxylic anhydride, 1, 8-
Examples thereof include naphthalene dicarboxylic anhydride, 2,3-anthracene dicarboxylic anhydride, and 1,9-anthracene dicarboxylic anhydride, and these may be used alone or as a mixture of two or more.

According to the method of the present invention, the starting materials diamine, tetracarboxylic dianhydride, tetramine and dicarboxylic anhydride are added to the organic solvent and reacted.
(A) A method in which a diamine, a tetramine, and a tetracarboxylic dianhydride are reacted, and then a dicarboxylic anhydride is added to continue the reaction. (Ii) A diamine, a tetramine, and a dicarboxylic anhydride are added and reacted. (D) adding diamine, tetramine, tetracarboxylic dianhydride and dicarboxylic anhydride simultaneously and reacting them.
After reacting diamine, tetracarboxylic dianhydride,
Any addition or reaction may be used, such as a method of adding tetramine, continuing the reaction, further adding a dicarboxylic anhydride, and continuing the reaction. The tetramine used in the present invention has the formula (5)

[0043]

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Wherein W is the same as defined above, W represents a tetravalent group having at least 4 carbon atoms,
The bond between (a) and (b) and the bond between (c) and (d) need to be bonded to adjacent carbon atoms. If they are not adjacent to each other, a ladder structure is not formed in a three-dimensional structure, so that the effects of the polyimide resin of the present invention cannot be obtained.

The amount of the tetracarboxylic dianhydride is 0.9 to 0.99 mole ratio, preferably 0.91 to 0.988 mole ratio, more preferably 0.915 mole ratio per mole of the total of diamine and tetramine. ０．９0.985 mole ratio, most preferably 0.92 to 0.98 mole ratio. 0.9
At less than the molar ratio, sufficient strength alone cannot be obtained,
If the molar ratio exceeds 9 mol, the viscosity at the time of melting is extremely high, and molding becomes difficult.

The amount of tetramine is 0.001 to 0.3 mole ratio per mole of diamine, preferably 0.001 to 0.3.
2 to 0.2 molar ratio, more preferably 0.005 to 0.1
Molar ratio, more preferably 0.008 to 0.08 molar ratio,
Most preferably, the molar ratio is in the range of 0.01 to 0.05. If the molar ratio is less than 0.001, the effect of the ladder structure does not appear. If the molar ratio exceeds 0.3, gelation occurs during synthesis, and the viscosity at the time of melting is extremely high, making molding difficult.

Further, the amount of dicarboxylic anhydride used for terminal blocking is 1 mole per total amount of diamine and tetramine.
It is necessary to adjust the total amount of tetracarboxylic dianhydride and dicarboxylic anhydride to be 1.0 to 2.0 in equivalent ratio. If the molar ratio is less than 1.0, the effect of terminating the terminal is not sufficiently exhibited. If the molar ratio is more than 2.0, the effect does not change so much, which is economically disadvantageous.

As the solvent used for the polymerization, for example, N, N
-Dimethylformamide, N, N-dimethylacetamide, N, N-diethylacetamide, N, N-dimethylmethoxyacetamide, N-methyl-2-pyrrolidone,
1,3-dimethyl-2-imidazolidinone, N-methylcaprolactam, 1,2-dimethoxyethane, bis (2
-Methoxyethyl) ether, 1,2-bis (2-methoxyethoxy) ethane, bis [2- (2-methoxyethoxy) ethyl] ether, tetrahydrofuran, 1,3
-Dioxane, 1,4-dioxane, pyridine, picoline, dimethyl sulfoxide, dimethyl sulfone, tetramethyl urea, hexamethyl phosphoramide, phenol, m-cresol, p-cresol, p-chlorophenol, anisole and the like. These may be used as a mixture. Among these, m-cresol, p-
Cresol is particularly preferred.

The reaction temperature is usually in the range of 0 ° C. to 250 ° C. Preferably 60 ° C to 240 ° C, more preferably 1 ° C to 240 ° C.
00 ° C to 220 ° C, more preferably 140 ° C to 210
The reaction may be carried out at a temperature in the range of 180C to 200C. The reaction pressure is not particularly limited,
It does not matter at all whether it is carried out under normal pressure or under pressure.

The reaction time varies depending on the reaction temperature, but is generally 1 hour or more, and particularly preferably in the range of 2 hours to 6 hours. If the reaction time is shorter than 1 hour, the molecular weight of the produced polymer will not be sufficiently increased. Even if the reaction time is longer than 6 hours, there is no great difference in the physical properties of the produced polymer.

When the polyimide of the present invention is subjected to melt molding, other thermoplastic resins such as polyethylene, polypropylene, polycarbonate, polyarylate, polyamide, polysulfone, polyethersulfone, and polyether may be used as long as the object of the present invention is not impaired. Ketone, polyetheretherketone, polyphenylene sulfide,
An appropriate amount of polyamide imide, polyether imide, modified polyphenylene oxide or the like can be blended according to the purpose.

Further, the following fillers and the like used in ordinary resin compositions may be used to such an extent that the object of the invention is not impaired. That is, reinforcement of abrasion resistance materials such as graphite, carborundum, silica stone powder, molybdenum disulfide, fluororesin, glass fiber, carbon fiber, boron fiber, silicon carbide fiber, carbon whisker, asbestos, metal fiber, ceramic fiber, etc. Materials, flame retardant materials such as antimony trioxide, magnesium carbonate, calcium carbonate, etc., electric property improving materials such as clay and mica,
Tracking resistance improving materials such as asbestos, silica and graphite, acid resistance improving materials such as barium sulfate, silica and calcium metasilicate, heat conductivity improving materials such as iron powder, zinc powder, aluminum powder and copper powder, and other glass beads,
Glass sphere talc, diatomaceous earth, alumina, Silasbarn,
Hydrated alumina, metal oxides, coloring agents and the like.

[0053]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Examples and Comparative Examples, but the present invention is not limited to these Examples. Example 1 359.2 g (0.975 mol) of 4,4'-bis (3-aminophenoxy) biphenyl and 206.1 g of pyromellitic anhydride were placed in a reaction vessel equipped with a stirrer, a reflux condenser and a nitrogen inlet tube. (0.945 mol), 5.35 g (0.025 mol) of 3,3'-diaminobenzidine, 16.3 g (0.11 mol) of phthalic anhydride and 2,200 g of m-cresol were charged and stirred. The mixture was heated to 200 ° C. and kept at 200 ° C. for 6 hours (molar ratio of tetracarboxylic dianhydride to 0.9 mol of the total amount of diamine and tetramine was 0.945). Next, toluene was added to the reaction solution, the precipitate was separated by filtration, and the precipitate was washed several times with toluene, and dried at 250 ° C. for 6 hours under a nitrogen atmosphere to obtain 505 g of a polyimide powder. The glass transition temperature Tg of this polyimide powder is 255 ° C., and the melting point Tm is 391 ° C.
(According to DSC; the same applies hereinafter). The logarithmic viscosity of this polyimide powder was 0.46 dl / g. Here, the logarithmic viscosity was determined using a mixed solvent of parachlorophenol and phenol (weight ratio 90:10) at a concentration of 0.5 g / 1.
It is a value measured at 35 ° C. in a 00 ml solvent. Using the polyimide powder obtained in this example, with a Koka type flow tester (CFT-500, manufactured by Shimadzu Corporation), the diameter is 0.1 c.
The change in melt viscosity with time was measured using an orifice having a length of 1 cm and a length of 1 cm. After maintaining the temperature at 420 ° C for 5 minutes,
It was partially extruded at a pressure of 00 kg / cm ² and its viscosity was measured. The remainder was partially extruded at a pressure of 100 kg / cm ² and its viscosity was measured. The relationship between the 420 ° C. holding time and the melt viscosity is shown in Table 1 (Table 1). Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. Furthermore, the obtained polyimide powder was dried at 200 ° C. for 20 hours under a nitrogen stream to sufficiently remove water, then supplied to a 25 mm vent type extruder, melt-extruded from a 3 mm diameter die at 400 ° C., and cooled and solidified. The resultant was cut with a pelletizer to obtain a polyimide pellet having a diameter of about 2 mm and a length of about 3 mm. The obtained polyimide pellets are injection-molded at a molding temperature of 400 ° C. and a mold temperature of 150 ° C. using a usual injection molding machine, and the heat distortion temperature (HD)
T) was measured. The HDT test method is ASTM D-6.
According to 48. The result was 235 ° C, and Comparative Example 1 described later was used.
It can be seen that it is rising compared to. Physical properties are summarized in Table 1 (Table 1).

Example 2 Instead of 3,3'-diaminobenzidine for tetramine, 3.45 g of 1,2,4,5-tetraaminobenzene
An experiment was performed in the same manner as in Example 1 except that (0.025 mol) was used, to obtain 501.2 g of a polyimide powder (total of 1 mol of diamine and tetramine, mol of tetracarboxylic dianhydride. Ratio 0.945). This polyimide powder has a glass transition temperature Tg of 254 ° C. and a melting point Tm of 389 ° C.
Met. The logarithmic viscosity of this polyimide powder is 0.1.
It was 46 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result is 23
4C, which is higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 3 Example 1 was repeated except that 5.75 g (0.025 mol) of 3,3 ', 4,4'-tetraaminophenyl ether was used instead of 3,3'-diaminobenzidine for tetramine.
An experiment was carried out in the same manner as described above to obtain 500.2 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.9 mol of the total amount of diamine and tetramine was 0.945). The glass transition temperature Tg of this polyimide powder is 256 ° C. and the melting point Tm
Was 391 ° C. The logarithmic viscosity of this polyimide powder was 0.46 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured.
The result was 237 ° C., which indicates that the temperature was higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 4 Example 1 was repeated except that 6.95 g (0.025 mol) of 3,3 ', 4,4'-tetraaminophenylsulfone was used instead of 3,3'-diaminobenzidine for tetramine.
An experiment was carried out in the same manner as described above to obtain 502.3 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.9 mol of the total amount of diamine and tetramine was 0.945). The glass transition temperature Tg of this polyimide powder is 255 ° C. and the melting point Tm
Was 390 ° C. The logarithmic viscosity of this polyimide powder was 0.47 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured.
The result was 235 ° C., which indicates that the temperature was higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 5 3,3 ', 4,4'-tetraaminophenyl ketone instead of 3,3'-diaminobenzidine for tetramine
An experiment was performed in the same manner as in Example 1 except that 05 g (0.025 mol) was used, to obtain 501.8 g of a polyimide powder (total amount of diamine and tetramine was 1 mol, and tetracarboxylic dianhydride was used. Molar ratio 0.945). The glass transition temperature Tg of this polyimide powder is 257 ° C., and the melting point Tm is 3
91 ° C. The logarithmic viscosity of this polyimide powder was 0.47 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result was 237 ° C., which indicates that the temperature was higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 6 3.21 g of 3,3'-diaminobenzidine was added to tetramine.
(0.015 mol), and experiment was conducted in the same manner as in Example 1 except that 1.38 g (0.010 mol) of 1,2,4,5-tetraaminobenzene was used to obtain 503.0 g of a polyimide powder. (The molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine).
The glass transition temperature Tg of this polyimide powder was 255 ° C., and the melting point Tm was 390 ° C. The logarithmic viscosity of this polyimide powder was 0.46 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result was 235 ° C., which indicates that the temperature was higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 7 An experiment was carried out in the same manner as in Example 1 except that 386.1 g (0.975 mol) of bis [4- (3-aminophenoxy) phenyl] ketone was used as the diamine, and 517.5 g of polyimide was used. A powder was obtained (molar ratio of tetracarboxylic dianhydride to 0.94 with respect to 1 mol of total amount of diamine and tetramine).
5). The glass transition temperature Tg of this polyimide powder is 258
° C and melting point Tm were 394 ° C. The logarithmic viscosity of this polyimide powder was 0.49 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding. The heat distortion temperature (HDT)
Was measured. The result was 239 ° C. It can be seen that it is higher than that of Comparative Example 2 described later. Physical properties are summarized in Table 1 (Table 1).

Example 8 To a tetracarboxylic dianhydride, 304.49 g of 3,3 ', 4,4'-benzophenonetetracarboxylic dianhydride was added.
(0.945 mol) was conducted in the same manner as in Example 1 to obtain 592.3 g of a polyimide powder (the total amount of the diamine and tetramine was 1 mol, and the mol of the tetracarboxylic dianhydride was 1 mol.) Ratio 0.945). The glass transition temperature Tg of this polyimide powder is 257 ° C., and the melting point Tm is 393 ° C.
Met. The logarithmic viscosity of this polyimide powder is 0.1.
It was 49 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result is 23
7 ° C. It can be seen that it is higher than that of Comparative Example 3 described later. Physical properties are summarized in Table 1 (Table 1).

Example 9 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, 64.2 g (0.3 mol) of 3,3'-diaminobenzidine was used as the tetramine. An experiment was performed in the same manner as in Example 1 except that 268.0 g (1.23 mol) of pyromellitic anhydride was used for tetracarboxylic dianhydride and 22.2 g (0.15 mol) of phthalic anhydride was used for dicarboxylic anhydride. Was carried out to obtain 606.2 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.94 with respect to 1 mol of the total amount of diamine and tetramine).
5). The glass transition temperature Tg of this polyimide powder is 260
° C and melting point Tm were 395 ° C. The logarithmic viscosity of this polyimide powder was 0.47 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. When the holding time was prolonged, the melt viscosity increased and the thermal stability was somewhat poor, but it was possible to obtain a molded product by injection molding. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. Result is 246 ° C
It can be seen that it is higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

EXAMPLE 10 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, and 0.214 g (0.00 mol) of 3,3'-diaminobenzidine was used as the tetramine.
Example 1 except that 206.1 g (0.945 mol) of pyromellitic anhydride was used as the tetracarboxylic dianhydride and 17.8 g (0.12 mol) of phthalic anhydride was used as the dicarboxylic anhydride. Perform the same experiment as in
Was obtained (a molar ratio of tetracarboxylic dianhydride to 0.1 mole per 1 mole of the total amount of diamine and tetramine).
945). The glass transition temperature Tg of this polyimide powder is 2
The melting point Tm was 389 ° C. The logarithmic viscosity of this polyimide powder was 0.47 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding.
DT) was measured. The result was 233 ° C., which indicates that the temperature was higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 11 312.5 g of phthalic anhydride (2.
An experiment was performed in the same manner as in Example 1 except that 11 mol) was used, to obtain 504.2 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.1 mol per 1 mol of the total amount of diamine and tetramine). 945). The glass transition temperature Tg of this polyimide powder was 255 ° C., and the melting point Tm was 391 ° C. The logarithmic viscosity of this polyimide powder is 0.46 d
1 / g. 4 of the polyimide powder obtained in this example
The change with time of the melt viscosity at 20 ° C. was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was obtained in Example 1.
A molded product was obtained by pelletization and injection molding in the same manner as described above, and the heat distortion temperature (HDT) was measured. Result is 235 ° C
It can be seen that it is higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 12 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, 64.2 g (0.3 mol) of 3,3'-diaminobenzidine was used as the tetramine. An experiment was performed in the same manner as in Example 1 except that 255.2 g (1.17 mol) of pyromellitic anhydride was used as tetracarboxylic dianhydride and 38.5 g (0.26 mol) of phthalic anhydride was used as dicarboxylic anhydride. Was carried out to obtain 614.2 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine).
The glass transition temperature Tg of this polyimide powder was 253 ° C., and the melting point Tm was 387 ° C. The logarithmic viscosity of this polyimide powder was 0.38 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. When the holding time was prolonged, the melt viscosity increased and the thermal stability was somewhat poor, but it was possible to obtain a molded product by injection molding. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result was 234 ° C., which indicates that the temperature was higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 13 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, 64.2 g (0.3 mol) of 3,3'-diaminobenzidine was used as the tetramine. An experiment was carried out in the same manner as in Example 1 except that 279.2 g (1.28 mol) of pyromellitic anhydride was used as tetracarboxylic dianhydride and 3.85 g (0.026 mol) of phthalic anhydride was used as dicarboxylic anhydride. Was carried out to obtain 603.2 g of a polyimide powder (a molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine).
9). The glass transition temperature Tg of this polyimide powder is 270
° C and melting point Tm were 402 ° C. The logarithmic viscosity of this polyimide powder was 0.76 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. When the holding time was prolonged, the melt viscosity increased and the thermal stability was somewhat poor, but it was possible to obtain a molded product by injection molding. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. Result is 260 ° C
It can be seen that it is higher than that of Comparative Example 1 described later. Physical properties are summarized in Table 1 (Table 1).

Example 14 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as a diamine, and 0.214 g (0.00 mol) of 3,3'-diaminobenzidine was used as a tetramine.
Example 1 except that 198.5 g (0.91 mol) of pyromellitic anhydride was used as the tetracarboxylic dianhydride and 31.1 g (0.21 mol) of phthalic anhydride was used as the dicarboxylic anhydride. An experiment was carried out in the same manner as described above to obtain 508.2 g of a polyimide powder (total amount of diamine and tetramine was 1).
The molar ratio of tetracarboxylic dianhydride to mol is 0.1.
9). The glass transition temperature Tg of this polyimide powder is 252.
° C and melting point Tm were 385 ° C. The logarithmic viscosity of this polyimide powder was 0.38 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding. The heat distortion temperature (HDT)
Was measured. The result was 246 ° C., and Comparative Example 2 described later was used.
It can be seen that it is rising compared to. Was. Physical properties are summarized in Table 1 (Table 1).

Example 15 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as a diamine, and 0.214 g (0.00 mol) of 3,3'-diaminobenzidine was used as a tetramine.
Example 1 except that 215.9 g (0.99 mol) of pyromellitic anhydride was used for tetracarboxylic dianhydride and 3.11 g (0.021 mol) of phthalic anhydride was used for dicarboxylic anhydride. Perform the same experiment as in
Was obtained (a molar ratio of tetracarboxylic dianhydride to 0.1 mole per 1 mole of the total amount of diamine and tetramine).
99). The glass transition temperature Tg of this polyimide powder is 26
4 ° C., melting point Tm was 395 ° C. The logarithmic viscosity of this polyimide powder was 0.72 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. When the holding time was prolonged, the melt viscosity increased and the thermal stability was somewhat poor, but it was possible to obtain a molded product by injection molding. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. Result is 264
° C, which is higher than that of Comparative Example 3 described later. Physical properties are summarized in Table 1 (Table 1).

[0068]

[Table 1] Note: The melt viscosity is a value measured at 420 ° C., and the unit is centipoise. The unit of Tg, Tm, and HDT is ° C.
The thickening ratio is a value obtained by dividing a value at 420 ° C./30 minutes by a value at 420 ° C./5 minutes.

Comparative Example 1 Example 1 was repeated except that 368.4 g (1.0 mol) of 4,4′-bis (3-aminophenoxy) biphenyl was used as a diamine and 3,3′-diaminobenzidine of tetramine was not used. An experiment was carried out in the same manner as in (1) to obtain 501.0 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to the total amount of 1 mol of diamine and tetramine was 0.945).
The glass transition temperature Tg of this polyimide powder was 250 ° C., and the melting point Tm was 385 ° C. The logarithmic viscosity of this polyimide powder was 0.46 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. However, the obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding.
The measurement result of DT) is 230 ° C., which indicates that the thermal properties are inferior to those of Examples 1 and 2 even though the logarithmic viscosity and the melt viscosity are almost the same. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 2 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as a diamine, and 196.1 g (0.9 mol) of pyromellitic anhydride was used as a tetracarboxylic dianhydride.
Mol), 29.7 g of phthalic anhydride in dicarboxylic anhydride
(0.2 mol), and the experiment was carried out in the same manner as in Example 1 except that 3,3′-diaminobenzidine was not used as the tetramine to obtain 500.1 g of a polyimide powder (total amount of diamine and tetramine). The molar ratio of tetracarboxylic dianhydride to 1 mol is 0.945). The glass transition temperature Tg of this polyimide powder is 247 ° C., and the melting point Tm is 383 ° C.
Met. The logarithmic viscosity of this polyimide powder is 0.1.
It was 37 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result is 22
9 ° C., which was lower than that obtained in Example 14. This is probably because the amount of tetramine was small, the ladder structure was not sufficiently formed in the polymer, and the effect of the invention was not sufficiently exhibited. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 3 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, and 215.9 g (0.9 mol) of pyromellitic anhydride was used as the tetracarboxylic dianhydride.
9 mol), and 2.97 phthalic anhydride in dicarboxylic anhydride.
g (0.02 mol), and experiment was conducted in the same manner as in Example 1 except that 3,3′-diaminobenzidine was not used as tetramine, to obtain 497.9 g of polyimide powder (total of diamine and tetramine). The molar ratio of tetracarboxylic dianhydride to the mole of 1 mole is 0.945). The glass transition temperature Tg of this polyimide powder is 262 ° C., and the melting point Tm is 3
93 ° C. The logarithmic viscosity of this polyimide powder was 0.71 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. When the holding time was prolonged, the melt viscosity increased and the thermal stability was slightly inferior, but a molded product could be obtained by injection molding. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding.
DT) was measured. The result was 249 ° C.
It was lower than that obtained in. This is probably because the amount of tetramine was small, the ladder structure was not sufficiently formed in the polymer, and the effect of the invention was not sufficiently exhibited. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 4 Example 1 was repeated except that 396.4 g (1.0 mol) of bis [4- (3-aminophenoxy) phenyl] ketone was used as the diamine and 3,3′-diaminobenzidine of tetramine was not used. An experiment was carried out in the same manner as described above to obtain 530.0 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.94 with respect to 1 mol of the total amount of diamine and tetramine).
5). The glass transition temperature Tg of this polyimide powder is 253.
° C and melting point Tm were 388 ° C. The logarithmic viscosity of this polyimide powder was 0.48 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. However, the obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding. The result of measurement of the heat distortion temperature (HDT) was 233 ° C., and the logarithmic viscosity and melt viscosity were almost the same. Nevertheless, it can be seen that the thermal properties are inferior to Example 7 in spite of the existence. Physical properties are summarized in Table 2 (Table 2).

COMPARATIVE EXAMPLE 5 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as a diamine, and 3,3 ', 4,4'-benzophenonetetraphenyl was used as a tetracarboxylic dianhydride. The experiment was carried out in the same manner as in Example 1 except that 304.49 g (0.945 mol) of carboxylic dianhydride was used and 3,3′-diaminobenzidine of tetramine was not used.
90.2 g of polyimide powder was obtained (the molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine). The glass transition temperature Tg of this polyimide powder was 252 ° C., and the melting point Tm was 387 ° C. The logarithmic viscosity of this polyimide powder is 0.48 dl / g.
Met. 420 ° C. of the polyimide powder obtained in this comparative example
The change with time of the melt viscosity was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. However, the obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding. The result of measurement of the heat distortion temperature (HDT) was 232.
It is understood that the thermal properties are inferior to Example 8 in spite of the fact that the temperature is ° C and the logarithmic viscosity and the melt viscosity are almost the same. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 6 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used for the diamine, 85.6 g (0.4 mol) of 3,3'-diaminobenzidine was used for the tetramine, An experiment was performed in the same manner as in Example 1 except that 287.9 g (1.32 mol) of pyromellitic anhydride was used as tetracarboxylic dianhydride and 23.7 g (0.16 mol) of phthalic anhydride was used as dicarboxylic anhydride. Was performed to obtain 641.4 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.94 with respect to 1 mol of the total amount of diamine and tetramine).
5). The glass transition temperature Tg of this polyimide powder is 261
° C and melting point Tm were 397 ° C. The logarithmic viscosity of this polyimide powder was 0.48 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. When the holding time was prolonged, the melt viscosity increased, the thermal stability was poor, and it was not possible to obtain a molded product by pelletization and injection molding. This is probably because the rigid ladder structure was increased in the polymer, and the thermoplastic property was lost. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 7 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, and 0.171 g (0.00 mol) of 3,3'-diaminobenzidine was used as the tetramine.
Example 1 except that 206.1 g (0.945 mol) of pyromellitic anhydride was used as the tetracarboxylic dianhydride and 16.3 g (0.11 mol) of phthalic anhydride was used as the dicarboxylic anhydride. An experiment was performed in the same manner as in
g of polyimide powder was obtained (the molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine). Glass transition temperature Tg of this polyimide powder
Was 252 ° C. and the melting point Tm was 386 ° C. The logarithmic viscosity of this polyimide powder was 0.46 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. However, the result was 231 ° C., which was not much different from that obtained in Example 1. This is probably because the amount of tetramine was small, the ladder structure was not sufficiently formed in the polymer, and the effect of the invention was not sufficiently exhibited. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 8 14.8 g (0.1%) of phthalic anhydride was added to dicarboxylic anhydride.
(Mol), the same experiment as in Example 1 was carried out,
498.1 g of polyimide powder was obtained (the molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine). The glass transition temperature Tg of this polyimide powder was 255 ° C., and the melting point Tm was 392 ° C. The logarithmic viscosity of this polyimide powder is 0.46 dl / g.
Met. 420 ° C. of the polyimide powder obtained in this comparative example
The change with time of the melt viscosity was measured. It can be seen that when the holding time is extended, the melt viscosity increases and the thermal stability is poor.
This is because the dicarboxylic anhydride has not reached the equivalent weight,
It is considered that the effect of terminal termination was not sufficiently exhibited. However, the obtained polyimide powder could be pelletized in the same manner as in Example 1, and a molded product could be obtained by injection molding. When the heat distortion temperature (HDT) was measured, the result was 236 ° C., and the heat resistance was higher than that obtained in Comparative Example 1. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 9 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, 66.2 g (0.3 mol) of 3,3'-diaminobenzidine was used as the tetramine. An experiment was performed in the same manner as in Example 1 except that 253.0 g (1.16 mol) of pyromellitic anhydride was used as tetracarboxylic dianhydride and 43.0 g (0.29 mol) of phthalic anhydride was used as dicarboxylic anhydride. Was carried out to obtain 615.5 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.8 mol per 1 mol of the total amount of diamine and tetramine).
9). The glass transition temperature Tg of this polyimide powder is 245
° C and melting point Tm were 381 ° C. The logarithmic viscosity of this polyimide powder was 0.35 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding. However, it was very brittle and was unsuitable for measuring the heat distortion temperature (HDT). This is probably because the molar ratio was too low, the molecular weight did not increase, and sufficient strength was not obtained. Physical properties are summarized in Table 2 (Table 2).

COMPARATIVE EXAMPLE 10 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as a diamine, and 0.214 g (0.00 mol) of 3,3'-diaminobenzidine was used as a tetramine.
Example 1 except that 196.3 g (0.9 mol) of pyromellitic anhydride was used for tetracarboxylic dianhydride and 31.1 g (0.21 mol) of phthalic anhydride for dicarboxylic anhydride. An experiment was carried out in the same manner as described above to obtain 504.1 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.8 mol per 1 mol of the total amount of diamine and tetramine).
9). The glass transition temperature Tg of this polyimide powder is 244
° C and melting point Tm were 379 ° C. The logarithmic viscosity of this polyimide powder was 0.34 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding. However, it was very brittle and was unsuitable for measuring the heat distortion temperature (HDT). This is probably because the molar ratio was too low, the molecular weight did not increase, and sufficient strength was not obtained. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 11 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used for the diamine, and 0.171 g (0.00 mol) of 3,3'-diaminobenzidine was used for the tetramine.
08 mol), 216.2 g (0.991 mol) of pyromellitic anhydride as the tetracarboxylic dianhydride and 4.5 g (0.03 mol) of phthalic anhydride as the dicarboxylic anhydride. Perform the same experiment as in
Was obtained (a molar ratio of tetracarboxylic dianhydride to 0.1 mole per 1 mole of the total amount of diamine and tetramine).
99). The glass transition temperature Tg of this polyimide powder is 26
2 ° C., melting point Tm was 393 ° C. The logarithmic viscosity of this polyimide powder was 0.71 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this example was measured. When the holding time was prolonged, the melt viscosity increased and the thermal stability was poor, but a molded product could be obtained by injection molding. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result is 249 ° C.
There was no great difference from that obtained in Comparative Example 3. This is presumably because the amount of tetramine was small and the ladder structure was not sufficiently formed in the polymer, so that the effects of the invention were not sufficiently exhibited. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 12 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used for the diamine, and 0.171 g (0.00 mol) of 3,3'-diaminobenzidine was used for the tetramine.
08 mol), 196.5 g (0.901 mol) of pyromellitic anhydride as the tetracarboxylic dianhydride and 31.1 g (0.21 mol) of phthalic anhydride as the dicarboxylic anhydride. An experiment was performed in the same manner as in
g of polyimide powder was obtained (the molar ratio of tetracarboxylic dianhydride to 0.9 mole per 1 mole of the total amount of diamine and tetramine). The glass transition temperature Tg of this polyimide powder is 2
The melting point Tm was 383 ° C. The logarithmic viscosity of this polyimide powder was 0.37 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. Even if the holding time is prolonged, there is almost no change in the melt viscosity, indicating that the thermal stability is good. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding.
DT) was measured. The result was 229 ° C., which was not much different from that obtained in Comparative Example 1. This is presumably because the amount of tetramine was small and the ladder structure was not sufficiently formed in the polymer, so that the effects of the invention were not sufficiently exhibited. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 13 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as a diamine, 66.2 g (0.3 mol) of 3,3'-diaminobenzidine was used as a tetramine. An experiment was performed in the same manner as in Example 1, except that 281.4 g (1.29 mol) of pyromellitic anhydride was used as tetracarboxylic dianhydride and 4.5 g (0.03 mol) of phthalic anhydride was used as dicarboxylic anhydride. Was performed to obtain 606.5 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.99 with respect to 1 mol of the total amount of diamine and tetramine).
1). The glass transition temperature Tg of this polyimide powder is 272.
° C and melting point Tm were 403 ° C. The logarithmic viscosity of this polyimide powder was 0.77 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. It can be seen that when the holding time is prolonged, the melt viscosity increases greatly and the thermal stability is poor. Pelletization of the obtained polyimide powder was attempted in the same manner as in Example 1, but the melt viscosity was high and a molded product could not be obtained. This is probably because the molar ratio was too high, the molecular weight increased, and the thermoplastic property was lost.

Comparative Example 14 36,4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as the diamine, and 0.214 g (0.00 mol) of 3,3'-diaminobenzidine was used as the tetramine.
Example 1 except that 216.2 g (0.991 mol) of pyromellitic anhydride was used as the tetracarboxylic dianhydride and 3.0 g (0.02 mol) of phthalic anhydride was used as the dicarboxylic anhydride. An experiment was performed in the same manner as described above to obtain 496.6 g of a polyimide powder (total amount of diamine and tetramine was 1).
The molar ratio of tetracarboxylic dianhydride to mole is 0.9
91). The glass transition temperature Tg of this polyimide powder is 26
The melting point Tm was 396 ° C at 5 ° C. The logarithmic viscosity of this polyimide powder was 0.73 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. It can be seen that when the holding time is prolonged, the melt viscosity increases greatly and the thermal stability is poor. Pelletization of the obtained polyimide powder was attempted in the same manner as in Example 1, but the melt viscosity was high and a molded product could not be obtained. This is probably because the molar ratio was too high, the molecular weight increased, and the thermoplastic property was lost.

Comparative Example 15 368.4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used as a diamine, 85.6 g (0.4 mol) of 3,3'-diaminobenzidine was used as a tetramine, An experiment was conducted in the same manner as in Example 1 except that 301.0 g (1.38 mol) of pyromellitic anhydride was used for tetracarboxylic dianhydride and 11.85 g (0.08 mol) of phthalic anhydride was used for dicarboxylic anhydride. Was carried out to obtain 609.6 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine).
9). The glass transition temperature Tg of this polyimide powder is 274
° C and melting point Tm were 405 ° C. The logarithmic viscosity of this polyimide powder was 0.80 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. It can be seen that when the holding time is prolonged, the melt viscosity increases greatly and the thermal stability is poor. Pelletization of the obtained polyimide powder was attempted in the same manner as in Example 1, but the melt viscosity was high and a molded product could not be obtained. This is because the rigid ladder structure increased in the polymer,
This is probably due to the loss of thermoplastic properties. Physical properties are summarized in Table 2 (Table 2).

Comparative Example 16 36,4 g (1.0 mol) of 4,4'-bis (3-aminophenoxy) biphenyl was used for the diamine, 85.6 g (0.4 mol) of 3,3'-diaminobenzidine was used for the tetramine, An experiment was performed in the same manner as in Example 1 except that 274.8 g (1.26 mol) of pyromellitic anhydride was used as tetracarboxylic dianhydride and 44.4 g (0.3 mol) of phthalic anhydride was used as dicarboxylic anhydride. Was performed to obtain 650.4 g of a polyimide powder (the molar ratio of tetracarboxylic dianhydride to 0.9 mol per 1 mol of the total amount of diamine and tetramine).
The glass transition temperature Tg of this polyimide powder was 253 ° C., and the melting point Tm was 387 ° C. The logarithmic viscosity of this polyimide powder was 0.40 dl / g. The change over time of the melt viscosity at 420 ° C. of the polyimide powder obtained in this comparative example was measured. When the holding time was prolonged, the melt viscosity was greatly increased and the thermal stability was poor, but a molded product by injection molding could be obtained. The obtained polyimide powder was pelletized in the same manner as in Example 1, and a molded product was obtained by injection molding, and the heat distortion temperature (HDT) was measured. The result was 235 ° C.
This is probably because the rigid ladder structure was increased in the polymer, and the thermoplastic property was lost. Physical properties are summarized in Table 2 (Table 2).

[0085]

[Table 2] Note: The melt viscosity is a value measured at 420 ° C., and the unit is centipoise. The unit of Tg, Tm, and HDT is ° C.
The thickening ratio is a value obtained by dividing a value at 420 ° C./30 minutes by a value at 420 ° C./5 minutes. In Comparative Examples 6, 13, 14, and 15, no molded product was obtained, and in Comparative Examples 9, 10, HDT could not be measured because the strength was too low.

[0086]

According to the method of the present invention, heat stability during processing is excellent, and although melt molding is possible,
Further, a polyimide resin having increased heat resistance can be provided. It is an inexpensive and simple method industrially, and the present invention is significant.

Continuation of front page (56) References JP-A-1-165623 (JP, A) JP-A-62-212435 (JP, A) JP-A-60-181128 (JP, A) JP-A-60-137963 (JP, A) JP-A-58-149916 (JP, A) JP-A-47-42996 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) C08G 73/00-73/26 C08L 79/00-79/08

Claims (4)

(57) [Claims] [Claim 1] The following formula (1) (Wherein X is selected from the group consisting of a direct bond, a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group, a sulfonyl group and an oxide. Y ₁ , Y ₂ , Y
₃ and Y ₄ each independently represent a group selected from the group consisting of hydrogen, lower alkyl group, lower alkoxy group, chlorine and bromine, and may be the same or different. R is an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group, a monocyclic aromatic group, a condensed polycyclic aromatic group, a non-condensed cyclic group in which aromatic groups are connected to each other directly or by a bridge member. A tetravalent group selected from the group consisting of aromatic groups; W represents a tetravalent group having at least 4 carbon atoms; a bond between (a) and (b), and (c) and ( The bond d) is bonded to carbon atoms adjacent to each other)). 2. W is the following formula (2): The polyimide resin according to claim 1, which is one or a mixture of two or more kinds selected from the group consisting of: 3. The method for producing a polyimide resin according to claim 1, wherein the diamine is represented by the following formula (3). (Wherein X is selected from the group consisting of a direct bond, a divalent hydrocarbon group having 1 to 10 carbon atoms, a hexafluorinated isopropylidene group, a carbonyl group, a thio group, a sulfinyl group, a sulfonyl group and an oxide. Y ₁ , Y ₂ , Y
₃ and Y ₄ each independently represent a group selected from the group consisting of hydrogen, lower alkyl group, lower alkoxy group, chlorine and bromine. Wherein the tetracarboxylic dianhydride is represented by the following formula (4): (Wherein, R represents an aliphatic group having 2 or more carbon atoms, a cycloaliphatic group,
And a tetravalent group selected from the group consisting of a monocyclic aromatic group, a condensed polycyclic aromatic group, and a non-condensed cyclic aromatic group in which the aromatic groups are connected to each other directly or by a crosslinking member. Is a tetracarboxylic dianhydride represented by the following formula (5): (Wherein W represents a tetravalent group having at least 4 carbon atoms, a bond between (a) and (b), and (c) and (d)
Are bonded to carbon atoms adjacent to each other), and the reaction formula is represented by the following formula (6). Wherein Z is selected from the group consisting of a monocyclic aromatic group, a fused polycyclic aromatic group, and a non-fused polycyclic aromatic group in which the aromatic groups are interconnected directly or by a bridging member. The reaction is carried out in the presence of a dicarboxylic anhydride represented by the following formula: wherein the amount of the tetracarboxylic dianhydride is 0.90 to 0.99 mol per 1 mol of the total of diamine and tetramine And the amount of tetramine is 0.001 to 0.3 mole ratio per mole of diamine, and the total amount of diamine and tetramine is 1 mole, and the amount of tetracarboxylic dianhydride and dicarboxylic anhydride is 1 mole. Total amount is 1.0 to equivalent ratio
Formula (1) which is 2.0 (Wherein, X, Y _{1 to} Y ₄ , W and R are the same as above) as a basic skeleton. 4. The method according to claim 1, wherein the tetramine is 3,3′-diaminobenzidine, 1,2,4,5-tetraaminobenzene,
', 4,4'-tetraaminophenyl ether, 3,3
', 4,4'-tetraaminophenylsulfone, 3,3
The production method according to claim 3, wherein the production method is one or a mixture of two or more selected from ', 4,4'-tetraaminophenyl ketone.