JPH09136958A - Production of polyimide resin particle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce nearly spherical large-particle-diameter polyimide resin particles by reacting a tetracarboxylic dianhydride (TA) with an acid-anhydride- group-free tetracarboxylic acid and its derivative (TD) and a diamine in a polar solvent. SOLUTION: TA is preferably an aromatic TA (e.g. pyromellitic dianhydride) in view of pressure resistance and heat resistance. TD is exemplified by an acid (e.g. pyromellitic acid) derived by opening at least part of the rings of TA or a half-ester prepared by reacting TA with an alcohol. The diamine is desired to be an aromatic diamine (e.g. 4,4-diaminodiphenyl ether) or an alicyclic diamine in view of heat resistance and pressure resistance. The mixing ratio among the respective components is such that 5-92mol of TA and 8-95mol of TD are used per 100mol of the diamine. The reaction temperature is 190-210 deg.C. The obtained resin particles have a mean particle diameter of 0.1-300μm and a specific surface area of 1-250m<2> /g.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for producing polyimide resin particles.

[0002]

2. Description of the Related Art As a method for producing a particulate polymer of polyimide, for example, a polyimide precursor is prepared by reacting aromatic tetracarboxylic dianhydride and aromatic diamine in an organic solvent at a relatively low temperature. A method of preparing a polyamic acid solution, and then introducing the solution into a poor solvent such as water to recover a precipitated polymer, followed by ring closure by heating to imidize (Japanese Patent Publication No. 38-5997), A method of reacting a uniform solution of an anhydride and a diamine in an organic solvent at a relatively high temperature to directly produce an imidized particulate polymer as a slurry, and recovering and purifying the same (JP-B-39-30).
No. 060, JP-A No. 57-200452) and the like are known.

However, in the former method, a two-step reaction, which is disadvantageous in terms of process, is used, and the resulting particulate polymer (polyimide) is a lump with a relatively large particle size, which is uneconomical mechanical. This was not an industrially advantageous method because it was made into fine particle powder by pulverization. Further, in the latter method, a particulate polymer (polyimide) of fine particles is directly obtained by a one-step reaction, but most of the obtained particulate polymer is a secondary particle in the form of agglomerates in which primary particles are aggregated, The obtained particulate polymer needs to be pulverized depending on the application, which is not economical. Furthermore, in both methods, the shape of the particles obtained is close to an amorphous shape, so it is suitable for applications requiring a spherical particle shape (for example, separation materials such as column packing materials for high performance liquid chromatographs). Has the drawback that it is not applicable.

[0004]

The invention according to claim 1 provides a method for producing polyimide resin particles in which the particles obtained are substantially spherical and have a large particle size. In addition to the effect of the invention described in claim 1, the invention described in claim 2 provides a method for producing a polyimide resin particle in which particles are less aggregated and particles are less damaged during synthesis.

[0005]

The present invention provides one or more compounds selected from (I) tetracarboxylic acid dianhydride, (II) tetracarboxylic acid having no acid anhydride group and derivatives thereof, and (III) A method for producing polyimide resin particles, which comprises reacting a diamine in a polar solvent to form polyimide resin particles. Further, the present invention has an average particle diameter of the polyimide resin particles of 0.1 to 300.
and a specific surface area of 1 to 250 m ² / g.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The method for producing polyimide resin particles of the present invention is selected from (I) tetracarboxylic dianhydride, (II) tetracarboxylic acid having no acid anhydride group and its derivative. It is characterized in that a polyimide resin particle is formed by reacting more than one kind of compound and (III) diamine in a polar solvent.

Examples of the (I) tetracarboxylic dianhydride in the present invention include aromatic tetracarboxylic dianhydrides (pyromellitic dianhydride, 3,3 ', 4,4'-
Benzophenone tetracarboxylic dianhydride, 3,3 ′,
4,4'-biphenyltetracarboxylic dianhydride, 1,
2,5,6-naphthalenetetracarboxylic dianhydride,
2,3,6,7-naphthalenetetracarboxylic dianhydride, 2,3,5,6-pyridinetetracarboxylic dianhydride, 1,4,5,8-naphthalenetetracarboxylic dianhydride, 3, 4,9,10-perylenetetracarboxylic dianhydride, 4,4'-sulfonyldiphthalic dianhydride, m
-Terphenyl-3,3 ', 4,4'-tetracarboxylic dianhydride, 4,4'-oxydiphthalic anhydride, 1,
1,1,3,3,3-hexafluoro-2,2-bis (2,3-dicarboxyphenyl) propane dianhydride,
1,1,1,3,3,3-hexafluoro-2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis (2,3-dicarboxyphenyl) propane dianhydride Anhydrous, 2,2-bis (3,4-dicarboxyphenyl) propane dianhydride, 2,2-bis [4
(2,3-Dicarboxyphenoxy) phenyl] propane dianhydride, 2,2-bis [4, (2,3-dicarboxyphenoxy) phenyl] propane dianhydride, 2,2-
Bis [4, (3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 1,1,1,3,3,3-hexafluoro-2,2-bis [4- (2,3-dicarboxy Phenoxy) phenyl] propane dianhydride, 1,1,
1,3,3,3-hexafluoro-2,2-bis [4-
(3,4-dicarboxyphenoxy) phenyl] propane dianhydride, 1,3-bis (3,4-dicarboxyphenyl) -1,1,3,3-tetramethyldisiloxane dianhydride, etc., and these Hydrogen-reduced form of aromatic tetracarboxylic dianhydride of alicyclic tetracarboxylic dianhydride (2,
3,5-tricarboxy-cyclopentyl acetic acid dianhydride, butane-1,2,3,4-tetracarboxylic acid dianhydride, etc., and the like, of which the pressure resistance and heat resistance of the obtained polyimide resin particles Aromatic tetracarboxylic acid dianhydrides are preferred from the viewpoint of properties. These are used alone or in combination of two or more.

In the present invention, (II) one or more compounds selected from tetracarboxylic acids having no acid anhydride group and derivatives thereof include, for example, partially ring-opening acids of the tetracarboxylic dianhydride. (Including all ring-opening acids), half-esters obtained by reacting the tetracarboxylic dianhydride with alcohol, and the like. Examples of the partially ring-opening acid of tetracarboxylic dianhydride include pyromellitic acid and the like. Pyromellitic acid can be obtained by ring-opening pyromellitic dianhydride with water. Examples of the half ester body include a half ester body of pyromellitic dianhydride. Pyromellitic dianhydride can be obtained by reacting pyromellitic dianhydride with an alcohol (preferably an alcohol having 1 to 4 carbon atoms). These (II) components are used alone or in combination of two or more.

Examples of the (III) diamine in the present invention include aliphatic diamines, alicyclic diamines, heterocyclic diamines, aromatic diamines, and silicon diamines, which have heat resistance and pressure resistance. From the viewpoints of the above, an aromatic diamine and an alicyclic diamine which is a hydrogen reduction product of the aromatic diamine are preferable.

As the aromatic diamine, for example, 4,
4'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenylmethane, 4,4-methylene-bis- (2,6-dimethylaniline), 4,4'-methylene-bis- (2 , 6-diethylaniline), 4,4'-methylene-bis- (2-
Methyl-6-ethylaniline), 4,4'-diaminodiphenyl sulfone, 3,3'-diaminodiphenyl sulfone, 4,4'-benzophenone diamine, 3,3'-
Benzophenone diamine, metaphenylenediamine, paraphenylenediamine, 4,4'-di (4-aminophenoxy) phenyl sulfone, 4,4'-di (4-aminophenoxy) benzene, 3,3-di (4-aminophenoxy) ) Benzene, 4,4'-di (3-aminophenoxy) benzene, 2,4'-diaminotoluene, 2,6-
Diaminotoluene, 4,4'-diaminodiphenylpropane, 4,4-diaminophenyl, 2,2-bis [4-
(4-Aminophenoxy) phenyl] propane, 2,2
-Bis [4- (3-aminophenoxy) phenyl] propane, 1,1,1,3,3,3-hexafluoro-2,
2-bis [4- (4-aminophenoxy) phenyl] propane and the like can be mentioned. These are used alone or in combination of two or more.

The blending amount of the component (I) in the present invention is
The amount is preferably 5 to 92 mol, and more preferably 10 to 92 mol, based on 100 mol of the component (III). No. If the amount is less than 5 mol, the molecular weight of the obtained polyimide resin particles tends to be small, and the shape tends not to be spherical. If the amount exceeds 92 mol, it is difficult to obtain substantially spherical polyimide resin particles having a large particle size. Tend.

The blending amount of the component (II) in the present invention is
The amount is preferably 8-95 mol, more preferably 8-90 mol, based on 100 mol of the component (III). If the amount is less than 8 mol, it tends to be difficult to obtain polyimide resin particles having a substantially spherical shape and a large particle size.
If it exceeds 5 mol, the molecular weight of the obtained polyimide resin particles tends to be small and the shape tends not to be spherical.

Examples of the polar solvent in the present invention include ketones (acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), aromatic solvents (toluene, xylene, etc.), esters (ethyl acetate, butyl acetate, etc.),
Alcohol solvents (methanol, ethanol, butanol, etc.), lactone solvents (γ-butyrolactone, ε-caprolactone, etc.), ether solvents (ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, triethylene glycol dimethyl ether, dioxane, tetrahydrofuran) Etc.), phenolic solvents (phenol,
Metacresol etc.), basic solvents (N-methylpyrrolidone, N, N-dimethylformamide, N, N-dimethylacetamide, N-methylcaprolactam etc.), water and the like. These are used alone or in combination of two or more. Also, among these polar solvents,
N-methylpyrrolidone is preferable in terms of boiling point, cost, safety and the like.

The polyimide resin particles in the present invention can be manufactured, for example, as follows. The component (I), the component (II), and the component (III) are 0 to 10
It was dissolved in a polar solvent at 0 ° C. to give a homogeneous solution, followed by
The temperature was raised to 190 to 210 ° C. in 5 to 5 hours, and the temperature was 0.
Polyimide resin particles are precipitated in the solution by reacting for 1 to 4 hours. At that time, it is preferable that water distilled during the reaction is promptly removed from the system.

Then, solid polyimide resin particles are separated and collected by a conventional method. As a method for separating and recovering solid polyimide resin particles, for example, the polyimide resin particles are separated by filtering the dispersion, and the cake of the obtained polyimide resin particles is boiled with a cleaning solvent that is miscible with a polar solvent. Examples include a method of washing and drying under reduced pressure at 70 to 150 ° C. Examples of the cleaning solvent that is miscible with the polar solvent include acetone and the like. The obtained solid polyimide resin particles can be subjected to heat treatment at 300 to 400 ° C. in an atmosphere of air or an inert gas, if necessary, to further complete imidization and increase the molecular weight. it can.

The average particle size of the polyimide resin particles in the present invention is preferably 0.1 to 300 μm.
It is more preferable that the thickness is ˜100 μm. If the average particle size is less than 0.1 μm, the particles tend to agglomerate with each other, and if the average particle size exceeds 300 μm, the particles tend to be damaged during synthesis. The specific surface area of the polyimide resin particles is preferably 1 to 250 m ² / g, 15 to
More preferably, it is 100 m ² / g. Specific surface area is 1m ²
If it is less than / g, the particles tend to agglomerate,
When it exceeds 250 m ² / g, there is a tendency that the particles are often broken during the synthesis. Examples of the method for adjusting the average particle diameter and the specific surface area of the polyimide resin particles to the above range include, for example, (I)
The total amount of component (II) and component (II) is 100 mol, and (I)
The components may be 10 to 92 moles, the component (II) may be 8 to 90 moles, and 100 moles of the component (III) may be reacted therewith.

The polyimide resin particles obtained by the production method of the present invention include a separation material (column packing material for high performance liquid chromatography), a gas or liquid adsorbent, a heat-resistant thixotropic agent for an overcoat material of electronic parts, It is useful as a heat-resistant organic filler for sliding materials.

[0018]

Next, the present invention will be described with reference to examples. Example 1 196.3 g (0.9 mol) of dried pyromellitic dianhydride was passed through a four-necked flask equipped with a thermometer, a stirrer, a nitrogen inlet tube and a water content meter while passing nitrogen gas. 25.4 g (0.1 mol) of meritic acid and 1686 g of N-methylpyrrolidone were added, the temperature was raised to 50 ° C. with stirring, and the temperature was kept at the same temperature for 0.5 hour to completely dissolve the solution into a uniform solution. To this, 200 g (1 mol) of 4,4′-diaminodiphenyl ether (DDE) was added and kept at 80 ° C. for 0.5 hours to completely dissolve into a uniform solution, and then 2.5 hours to 200 ° C. The temperature was raised and the reaction was carried out at the same temperature for 2 hours. On the way, precipitation of polyimide resin particles was observed at 135 ° C. Further, during the reaction, distilled water was promptly removed from the system.

The yellow-brown polyimide resin particles dispersed in the N-methylpyrrolidone solution were recovered by filtration, and further, these were boiled twice in acetone (65 ° C., 120 minutes) and at 100 ° C. under reduced pressure. After drying for 5 hours, polyimide resin particles were obtained. The infrared absorption spectrum of the obtained polyimide resin particles was measured and found to be 1780 cm ^-1.
Absorption of imide group was observed. A scanning electron micrograph of the obtained polyimide resin particles is shown in FIG.
The amounts and characteristics of the obtained polyimide resin particles were evaluated by the following methods, and the results are shown in Table 1.

(Characteristic Evaluation Method) (1) Particle Shape: Scanning Electron Micrograph (3,000
I double-checked) (2) Aggregation state: scanning electron micrograph (3,000
I double-checked) (3) Average particle size: 50 independent particle sizes were measured using a scanning electron micrograph, and the average value was obtained. (4) Specific surface area: 0.35 g of polyimide resin particles were sufficiently pretreated (130 ° C., ultravacuum), and soapmatic: Model 1800 type (N ₂ adsorption type specific surface area measuring instrument, manufactured by Carlo Erba Co.) was used. Then, the specific surface area (surface area per unit weight) was measured.

Example 2 Dried pyromellitic dianhydride 152.6 g (0.
7 mol) and 76.2 g (0.3 mol) of pyromellitic acid
And except that N-methylpyrrolidone was 1710 g,
Dried polyimide resin particles were obtained in the same manner as in Example 1. As a result of measuring the infrared absorption spectrum of the obtained polyimide resin particles, absorption of an imide group was recognized at 1780 cm ^-1 . A scanning electron micrograph of the obtained polyimide resin particles is shown in FIG. The amount and characteristics of the obtained polyimide resin particles were evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Example 3 65.4 g (0.3% of dried pyromellitic dianhydride)
Mol), pyromellitic acid (178 g, 0.7 mol) and N-methylpyrrolidone (1773 g), but in the same manner as in Example 1 to obtain dried polyimide resin particles. As a result of measuring the infrared absorption spectrum of the obtained polyimide resin particles, absorption of an imide group was recognized at 1780 cm ^-1 . A scanning electron micrograph of the obtained polyimide resin particles is shown in FIG. The amount and characteristics of the obtained polyimide resin particles were evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Example 4 19.62 g (0.
09 mol), pyromellitic acid 2.54 g (0.01 mol), p-phenylenediamine (PPD) 10.8 g
Dry polyimide resin particles were obtained in the same manner as in Example 1 except that (0.1 mol) and N-methylpyrrolidone were 295 g. As a result of measuring the infrared absorption spectrum of the obtained polyimide resin particles, absorption of an imide group was recognized at 1780 cm ^-1 . The amount and characteristics of the obtained polyimide resin particles were evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Example 5 10.9 g (0.0%) of dried pyromellitic dianhydride was used.
5 mol), 12.7 g (0.05 mol) of pyromellitic acid, 10.8 g (0.1 mol) of PPD and 309 g of N-methylpyrrolidone, and drying in the same manner as in Example 4. The obtained polyimide resin particles were obtained. As a result of measuring the infrared absorption spectrum of the obtained polyimide resin particles, absorption of an imide group was recognized at 1780 cm ^-1 . The amount and characteristics of the obtained polyimide resin particles were evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 1 Drying was carried out in the same manner as in Example 1 except that 218 g (1 mol) of dried pyromellitic dianhydride, 1672 g of N-methylpyrrolidone were used and pyromellitic acid was not used. The obtained polyimide resin particles were obtained. As a result of measuring the infrared absorption spectrum of the obtained polyimide resin particles, absorption of an imide group was recognized at 1780 cm ^-1 . A scanning electron micrograph of the obtained polyimide resin particles is shown in FIG. The amount and characteristics of the obtained polyimide resin particles were evaluated in the same manner as in Example 1, and the results are shown in Table 1.

Comparative Example 2 25.4 g (0.1 mol) of pyromellitic acid and 408.6 g of N-methylpyrrolidone were placed in the same apparatus as in Example 1 while passing nitrogen gas, and the temperature was raised to 75 ° C. with stirring. The solution was kept at the same temperature for 0.5 hour and completely dissolved to obtain a uniform solution. To this, add 20.0 g (0.1 mol) of DDE,
The temperature was raised to 200 ° C. in 2.5 hours, and the reaction was carried out at the same temperature for 2 hours. During the reaction, distilled water was immediately removed from the system.
Since a particulate polymer dispersed in N-methylpyrrolidone was obtained, this was recovered by filtration, and after repeating acetone boiling twice twice, it was dried under reduced pressure at 100 ° C. for 5 hours to obtain a dried polyimide resin. The particles were obtained. As a result of measuring the infrared absorption spectrum of the obtained polyimide resin particles, absorption of an imide group was recognized at 1780 cm ^-1 . A scanning electron micrograph of the obtained polyimide resin particles is shown in FIG. The amount and characteristics of the obtained polyimide resin particles were evaluated in the same manner as in Example 1, and the results are shown in Table 1.

[0027]

[Table 1]

As is clear from the results shown in Table 1, Comparative Example 1
The polyimide resin particles obtained by the production method of 1 had a high tendency to aggregate, whereas the polyimide resin particles obtained by the production methods of Examples 1 to 5 had a low tendency to aggregate. Further, the polyimide resin particles obtained by the production method of Comparative Example 2 were amorphous, whereas the polyimide resin particles obtained by the production methods of Examples 1 to 5 were substantially spherical. From Examples 1 to 5, it can be seen that when the amount of the component (II) used increases, the average particle size tends to remarkably increase.

[0029]

The method for producing polyimide resin particles according to claim 1 is capable of producing polyimide resin particles having a substantially spherical shape and a large particle size, and the obtained polyimide resin particles are It is useful for separation materials (column packing materials for high performance liquid chromatographs), gas and liquid adsorbents, heat-resistant thixotropic agents for overcoat materials of electronic parts, heat-resistant organic fillers for sliding materials, etc. The method for producing polyimide resin particles according to claim 2 is advantageous in that it has the effects of the method for producing polyimide resin particles according to claim 1, and further that there is little aggregation of particles and less damage to particles during synthesis.

[Brief description of the drawings]

FIG. 1 is a scanning electron micrograph showing the particle structure of polyimide resin particles obtained in Example 1.

2 is a scanning electron micrograph showing the particle structure of polyimide resin particles obtained in Example 2. FIG.

FIG. 3 is a scanning electron micrograph showing the particle structure of polyimide resin particles obtained in Example 3.

4 is a scanning electron micrograph showing the particle structure of polyimide resin particles obtained in Comparative Example 1. FIG.

5 is a scanning electron micrograph showing a particle structure of polyimide resin particles obtained in Comparative Example 2. FIG.

Claims (2)

[Claims] 1. An (I) tetracarboxylic dianhydride, (I
(I) one or more compounds selected from tetracarboxylic acids having no acid anhydride group and derivatives thereof, and (III)
A method for producing polyimide resin particles, which comprises reacting a diamine in a polar solvent to form polyimide resin particles. 2. The average particle diameter of the polyimide resin particles is 0.
The method for producing polyimide resin particles according to claim 1, which has a specific surface area of 1 to 300 m and a specific surface area of 1 to 250 m ² / g.