JP4863292B2 - Method for producing polyimide - Google Patents

Description

  The present invention relates to a method for producing polyimide, and more particularly to a production method capable of producing a polyimide having a fine particle structure in which elongated strips are assembled.

Polyimide has favorable properties such as electrical insulation and high heat resistance, and is therefore used in various fields, and various methods for producing polyimide have been proposed (for example, Patent Document 1, Patents). Reference 2 and Patent Document 3).
Patent Document 1 states that “a polyimide whisker that can be suitably added as a fiber, film, or resin molding material that can improve the elastic modulus and softening temperature without impairing surface properties, and a method for producing the same. ”(Paragraph No. 0007 in the detailed description of the invention), which is a paraphenylene pyromellitic imide represented by the formula (1)“ shown in paragraph No. 0009 ”and Whisker's A polyimide whisker having a diameter d of 0.5 nm <d <50 nm and a length of 5 times or more of the diameter, and a polyamide having a concentration of 0.05 to 30% by weight in the production method This is a method for producing a polyimide whisker obtained by imidizing an acid solution with a dehydrating condensing agent. A method for producing a polyimide whiskers endcapped with amine or acid anhydride. "What is disclosed.
Patent Document 2 provides “a polyimide whisker that is well dispersed in an aromatic polyamide matrix and effective in improving physical properties and a method for producing the same” (paragraph number 0015 in the detailed description of the invention). The whisker diameter d is 0.5 nm <d <50 nm, and the length thereof is the diameter of the polyimide composed mainly of the repeating unit represented by the formula (1) “shown in Paragraph No. 0018. Polyimide whisker having 5 times or more of the above, and having a haze of a polyimide whisker dispersion solution having a concentration of 0.1% by weight in an N-methyl-2-pyrrolidone solvent is 20 or less. In the detailed description of the invention, paragraph numbers 0017 to 0019) and “an acid anhydride and p-phenylene in a solvent containing pyromellitic dianhydride as a main component. A polyamic acid solution is obtained by reacting with a diamine containing an amine as a main component. A polyamic acid solution having a concentration of 0.05 to 30% by weight is heated to 80 ° C. or higher, and then a dehydrating condensing agent is added. A process for producing a polyimide whisker having a whisker diameter d of 0.5 nm <d <50 nm and a length of 5 times or more of the diameter. , Paragraph number 0024).
Patent Document 3 discloses that “a method for producing a polyimide whisker with improved dispersibility aimed at exerting a higher effect when applied as a resin reinforcing agent is provided. "Providing a good polyimide whisker" (paragraph number 0012 in the detailed description of the invention), "an acid anhydride containing pyromellitic dianhydride as a main component and paraphenylenediamine as a main component When a dehydrating condensing agent is added to a polyamic acid solution having a concentration of 0.05 to 30% by weight obtained from a polymerization reaction with the diamine to perform an imidization reaction, a heterocyclic compound is used as an amine catalyst. (In the detailed description of the invention, paragraph number 0014) comprising polyimide having as a main component a repeating unit represented by formula (1) shown in paragraph number 0015. And a whisker diameter d of 0.5 nm <d <50 nm, and a method for producing a polyimide whisker whose length is three times or more of the diameter ”(paragraph number 0016 in the detailed description of the invention). Yes.

JP-A-2004-168858 (for example, paragraph numbers 0007 to 0010 in the detailed description of the invention) JP-A-2004-285484 (for example, paragraph numbers 0015 to 0024 in the detailed description of the invention) JP-A-2004-307626 (for example, paragraph numbers 0012 to 0016 in the detailed description of the invention)

However, as described above, the method for producing a polyimide disclosed in Patent Document 1 is “a polyimide whisker obtained by imidizing a polyamic acid solution having a concentration of 0.05 to 30% by weight using a dehydrating condensing agent. It is also a manufacturing method of polyimide whiskers that are end-capped with an amine or acid anhydride at the time of polyamic acid polymerization. ”It was necessary to use a polyamic acid solution and a dehydrating condensing agent.
As described above, the method for producing a polyimide disclosed in Patent Document 2 is “polyamide by reacting an acid anhydride containing pyromellitic dianhydride as a main component with a diamine containing paraphenylenediamine as a main component in a solvent. After obtaining an acid solution and heating a polyamic acid solution having a concentration of 0.05 to 30% by weight to 80 ° C. or higher, a dehydrating condensing agent is added and imidized ”. This also required the use of a polyamic acid solution and a dehydrating condensing agent.
As described above, the method for producing a polyimide disclosed in Patent Document 3 is “the concentration obtained from a polymerization reaction of an acid anhydride containing pyromellitic dianhydride as a main component and a diamine containing paraphenylenediamine as a main component is 0. When the imidization reaction is performed by adding a dehydrating condensing agent to a 0.05 to 30% by weight polyamic acid solution, a heterocyclic compound is used as an amine catalyst. This is also a polyamic acid solution and a dehydrating condensing agent. It was necessary to use and.
Examples of such dehydration condensing agents include “acid anhydrides such as acetic anhydride, benzoic anhydride, trifluoroacetic acid dianhydride; chlorides such as phosgene, thionyl chloride, tosyl chloride, nicotyl chloride; phosphorus trichloride, triphosphite triphosphate. Phosphorus compounds such as phenyl and diethyl phosphate cyanide; condensing agents such as N, N′-2 substituted carbodiimides such as N, N′-dicyclohexylcarbodiimide ”(Patent Document 1, paragraph No. 0030) and dehydration Since care must be taken in handling such as preventing water absorption of the condensing agent, there has been a problem that the implementation of the production method is complicated.

  The present invention has been made in view of such a conventional method for producing polyimide, and an object of the present invention is to provide a novel method for producing polyimide.

The present inventor has found that a polyimide can be produced by using a predetermined compound as a monomer and polymerizing the compound in a solvent, and has completed the present invention.
That is, the polyimide production method of the present invention (hereinafter referred to as “the present production method”) comprises polymerizing a compound represented by the following formula (I) (hereinafter referred to as “compound (I)”) in a solvent, A polyimide production method characterized in that a polyimide having a repeating unit represented by the following formula (II) is precipitated as a solid.
(In the formula, one of X1 and X2 is a hydrogen atom, the other means a hydrogen atom, an alkyl group, or an aryl group, and X3 means a hydrogen atom or an acyl group.)

In addition, the production method includes the following aspects (a) to (ri).
(A) The above production method, wherein X3 in formula (I) is a hydrogen atom.
(B) The above production method, wherein either one of X1 and X2 in formula (I) is a methyl group or an ethyl group.
(C) A dissolution step in which all of the compound (I) is completely dissolved in the solvent, and a precipitation step in which, after the dissolution step, a polyimide having a repeating unit represented by the formula (II) is precipitated as a solid from the solution. And the above manufacturing method.
(D) The production method of (c) above, wherein the solvent contains an aromatic compound.
(E) The above aromatic compound is a mixture of one or more selected from the group consisting of diisopropylnaphthalene, diethylnaphthalene, ethyl-isopropylnaphthalene, cyclohexyldiphenyl, diethylbiphenyl, triethylbiphenyl, and dibenzyltoluene. D) Manufacturing method.
(F) The production method of (e) above, wherein the solvent is dibenzyltoluene.
(G) The above production method, wherein the polymerization is carried out in a temperature range of 240 ° C to 350 ° C.
(H) The weight W (g) of the polyimide produced when assuming that the polyimide having the repeating unit represented by the formula (II) is produced at a yield of 100% from the compound (I) used for polymerization. The above-mentioned production method, wherein the ratio (percent) of the solvent to the volume V (ml) ((W / V) × 100) is in the range of 0.5 to 12.0.
(I) The above production method, wherein the produced polyimide forms a fine particle structure in which elongated strips are gathered.

The present invention also provides polyimide.
The polyimide of the first invention (hereinafter referred to as “first polyimide”) is a polyimide that can be obtained by the above-described production method.
The polyimide of the second invention (hereinafter referred to as “second polyimide”) is a polyimide having a repeating unit represented by the following formula (II) and having a fine particle structure in which elongated strips are gathered.

  In this production method, the compound (I) represented by the above formula (I) is polymerized in a solvent (compounds (I) undergo condensation polymerization), and a polyimide having a repeating unit represented by the above formula (II) is obtained. It is a manufacturing method of polyimide characterized by making it precipitate with solid. As in the present production method, a method for producing a polyimide by condensation-polymerizing the compound (I) in a solvent and precipitating a polyimide having a repeating unit represented by the above formula (II) as a solid is conventionally known. First, this manufacturing method is a novel polyimide manufacturing method. This production method is a polymerization agent that promotes polymerization such as a dehydration condensation agent as in the polyimide production methods disclosed in Patent Documents 1 to 3 described above (as described above, the handling of such a polymerization agent is usually In this respect, this production method can easily produce a polyimide (compared to a conventional polyimide production method).

In the above formula (I) showing the compound (I) as a monomer, one of X1 and X2 is a hydrogen atom, the other means a hydrogen atom, an alkyl group, or an aryl group, and X3 is hydrogen. An atom or an acyl group is meant.
One of X1 and X2 is a hydrogen atom, but one of the other (when X1 is one of these (hydrogen atom), X2 is the other one and X2 is one of the other ( In the case of a hydrogen atom), X1 is the other one.) Means a hydrogen atom, an alkyl group or an aryl group, preferably an alkyl group, and most preferably a methyl group or an ethyl group. . Examples of the alkyl group include linear or branched alkyl groups having 1 to 20, preferably 1 to 10, and more preferably 1 to 6 carbon atoms. Specifically, a methyl group, Examples of the alkyl group include linear and branched alkyl groups such as ethyl group, n-propyl group, isopropyl group, n-butyl group, t-butyl group, n-pentyl group, and n-hexyl group, most preferably methyl group. Or it is an ethyl group. Examples of the aryl group include a phenyl group, a naphthyl group, and a benzyl group.
X3 means a hydrogen atom or an acyl group, preferably a hydrogen atom. The acyl group is represented as RCO- (wherein R represents an alkyl group or an aryl group), and examples of R include a methyl group, an ethyl group, and a phenyl group. It is.

  Compound (I) may be prepared by various methods and is not limited at all. However, when X3 is a hydrogen atom, 4-nitrophthalic anhydride (4-nitro-1,2-benzenecarboxylic anhydride After adding a 4-nitrotrophic anhydride (4NPHAH, see FIG. 1) to open a 5-membered ring of 4NPHAH and then reducing the nitro group to an amino group, X1 and X2 Since two kinds of structural isomers are generated depending on which of them is a hydrogen atom, each of these two kinds of structural isomers may be separated and purified. If there is no particular problem (for example, the structure or yield of polyimide produced by each of the two types of structural isomers does not change much as in the examples described later), the two types of structural isomers. Each may be used as a mixture without separation and purification.

  The solvent for polymerizing the compound (I) dissolves the compound (I) without causing unnecessary reaction with the compound (I), and the conditions (for example, polymerization temperature) in which the compounds (I) are polymerized with each other. Any compound may be used as long as it is stable and can precipitate a polyimide produced by polymerization as a solid (for example, a powder or a granule). An organic compound having a high boiling point (higher than the polymerization temperature) does not cause unnecessary reaction with (I) and is stable at the polymerization temperature (usually high temperature) at which the compounds (I) are polymerized with each other. A solvent is preferable, and it is preferable to contain an aromatic compound in order to stably and sufficiently dissolve the compound (I) as an aromatic compound (more preferably, the solvent is made of an aromatic compound). The aromatic compound may be a mixture of one or more selected from the group consisting of diisopropylnaphthalene, diethylnaphthalene, ethyl-isopropylnaphthalene, cyclohexyldiphenyl, diethylbiphenyl, triethylbiphenyl, dibenzyltoluene, It is preferable if the solvent is dibenzyltoluene because the solvent has the above-described properties required for the solvent. In addition, since such dibenzyltoluene is commercially available as a heat medium used at high temperatures, such a commercially available product may be used as the solvent. The trade name “Barrel Therm 400” manufactured by Co., Ltd. (heat medium oil for high boiling point and high temperature: the main component is a dibenzyltoluene mixture) may be used.

In this production method, the compound (I) is completely dissolved in the solvent, and after the dissolution step, the polyimide having the repeating unit represented by the formula (II) is precipitated as a solid from the solution. And a precipitation step.
First, in the dissolution step, all of the compound (I) is completely dissolved in the solvent to form a solution, and in the precipitation step after the dissolution step, a polyimide having a repeating unit represented by the above formula (II) is contained in the solution. Since it precipitates as a solid, the solute compound (I) completely dissolved in the solution undergoes a polymerization reaction, and the polyimide produced by the polymerization reaction precipitates as a solid from the solution. As a result, since the polyimide precipitated as a solid from the solution is precipitated as fine particles of powder or granules, the subsequent use of the polyimide (for example, used as a reinforcing material kneaded into the plastic in order to reinforce the plastic) or. Make handling easier. This means that when the compound (I) is polymerized by the so-called bulk polymerization method (when only the monomer compound (I) is heated to the polymerization temperature without using a solvent as in the present production method), the bulk is formed. This is very different from the fact that the polyimide is produced and difficult to handle. The action and mechanism of the compound (I) as a solute completely dissolved in the solution undergoes a polymerization reaction, and the polyimide produced by the polymerization reaction is precipitated as a solid from the solution. Although not, polyimide can form a fine particle structure in which elongated strips are gathered. This “fine particle structure in which elongated strips are gathered” will be described in detail later.
In order to produce a polyimide having a fine particle structure in which such elongated strips are aggregated, at least when the polyimide is precipitated as a solid (precipitation step), it is preferable that the solution does not flow so much that stirring is not particularly performed. preferable.
Further, the polyimide having the repeating unit represented by the formula (II) precipitated as a solid in the precipitation step is separated from the solvent and recovered. This recovery is performed by separating a liquid solvent and a solid (for example, powder or granular) polyimide, and may be performed by a method such as filtration, stationary separation, or centrifugal separation. If impurities or the like adhere to the polyimide, the impurities can be removed by washing or the like.

  If the temperature at which the compound (I) is polymerized in the solvent is too low, the polymerization reaction between the compounds (I) does not proceed well (the polymerization reaction rate becomes too low), the polymerization reaction does not occur or the reaction time is long. If it is too high, the compound (I) or the solvent may be thermally decomposed. Therefore, depending on the type of the compound (I) to be used and the solvent, etc. In general, it is preferably 240 ° C or higher (as the lower limit), more preferably 260 ° C or higher, most preferably 280 ° C or higher, and conversely (as the upper limit), preferably 350 ° C or lower. More preferably, it is 340 degrees C or less, Most preferably, it is 330 degrees C or less (Therefore, Usually, Preferably it is 240 to 350 degreeC, More preferably, it is 260 to 340 degreeC. Most preferably from 280 ℃ ~330 ℃.).

  The time for polymerizing compound (I) in a solvent is not limited as long as it is appropriately determined so that a desired degree of polyimide is precipitated, but if it is too short, the polymerization reaction between compounds (I) will occur. Since it does not proceed well and sufficient polyimide cannot be obtained, and if it is too long, it takes time to increase the amount of polyimide obtained, so depending on the compound (I) used, the polymerization temperature, the type of the solvent, etc. , And preferably within a range in which these are compatible, usually (as the lower limit), preferably 1 hour or longer, more preferably 2 hours or longer, most preferably 3 hours or longer, and conversely (as the upper limit) ) Preferably 48 hours or less, more preferably 36 hours or less, most preferably 24 hours or less (thus usually preferably 1 hour to 48 hours, Ri is preferably 2 to 36 hours, and most preferably 3 to 24 hours.).

If the ratio of the compound (I) to the volume of the solvent used for the polymerization (that is, the concentration of the compound (I) as a monomer in the solvent) is too large, the compound (I) does not dissolve well in the solvent and the solvent is used. The problem is that the structure of the polyimide that is produced cannot be controlled well (for example, a state close to bulk polymerization may occur), and if it is too small, the amount of polyimide that precipitates as a solid decreases (by dissolving in the solvent, the polyimide In this case, the yield of polyimide may be reduced.
The weight W (g) of the polyimide formed when it is assumed that polyimide (polyimide having a repeating unit represented by the above formula (II)) is generated from the compound (I) used for polymerization at a yield of 100% (ie, , W is a mass excluding components that are eliminated when it is assumed that the compound (I) used for the polymerization becomes a polyimide by polymerization when it is assumed to be a polyimide in 100% yield). If the concentration in the solvent of the compound (I) as a monomer is shown as a value ((W / V) × 100) (unit: g / ml)) obtained by multiplying the value divided by the volume V (ml) by 100, Usually (as the lower limit), preferably 0.5 or more, more preferably 0.8 or more, most preferably 1.0 or more, conversely (as the upper limit), preferably 12.0 or less, More preferably 11. Or less, most preferably 10.0 or less (thus usually 0.5 to 12.0, more preferably 0.8 to 11.0, most preferably 1.0 to 10.0). is there.).

In this production method, compound (I) is dissolved in the solvent, compound (I) is polymerized in the solvent to form a polyimide, and the polyimide is precipitated in the solvent as a solid, thereby generating a polyimide structure. It can be well controlled to form a fine grain structure in which elongated strips are assembled.
Here, the “elongated belt-like body” means a length L along the longitudinal direction and a maximum dimension D in a cross section perpendicular to the longitudinal direction (the length of the longest line segment passing through the inside in the cross section). ) And the ratio (L / D) is usually 5 or more, preferably 10 or more, most preferably 20 or more (there is no particular upper limit on the ratio (L / D)) However, it is usually several hundred (for example, about 200 to 300) or less.) Further, the size (diameter) of the “fine particle structure in which elongated strips are gathered” is not particularly limited, but usually, individual fine particles can be observed by observation with a microscope (for example, an electron microscope with a magnification of several hundred times or more). In general, it is preferably 0.1 μm or more (as the lower limit), more preferably 0.5 μm or more, most preferably 1 μm or more, and conversely (as the upper limit), preferably 100 μm. Or less, more preferably 50 μm or less, and most preferably 10 μm or less (thus usually 0.1 μm to 100 μm, more preferably 0.5 μm to 50 μm, most preferably 1 μm to 10 μm). ). The ratio (L / D) may be adjusted by adjusting either one or both of D and L. For example, D is a polyimide to be formed (a polyimide having a repeating unit represented by the above formula (II)) ) Can be reduced by using the above-mentioned poor solvent as the solvent (by polymerizing in a poor solvent, the supersaturation degree of the precipitated polyimide oligomer is increased, and a large number of small crystal nuclei are formed, resulting in And D increases.) If the crystal growth is continued, L increases (for example, a monomer or an oligomer may be added into the polymerization system (the solvent) to continue the crystal growth). .)
Polyimide having a fine particle (powder, granule, etc.) structure in which such elongated strips are aggregated has a fibrous fine structure and is kneaded and mixed with plastic to reinforce other plastics (resin materials). It is effectively used as a reinforcing material (also called a reinforcing filler or a reinforcing filler, and conventionally glass fiber or the like has been frequently used). In particular, engineering plastics having polarity in the molecule such as polyamide, polyimide, polyester, polyethersulfone, polyetherketone, polyamideimide, polyethernitrile, etc. are used as the base resin, and the “fine particle structure in which elongated strips of the present invention are assembled” By adding “polyimide having”, effective reinforcement can be performed by the affinity between the base resin and the polyimide of the present invention (both have polarity in the molecule).

  In both the first polyimide and the second polyimide, as will be described later, when wide-angle X-ray scattering (WAXS) measurement is performed, halo (a wide peak) derived from amorphous (amorphous structure) is not observed and high crystallinity is obtained. It is insoluble even when immersed in concentrated sulfuric acid (specifically 97%) at room temperature (25 ° C.) for 24 hours, and has a sufficient degree of polymerization, high crystallinity and chemical resistance. It is.

  Examples are given below in order to specifically describe the present invention. However, the present invention is not limited by these examples.

(Synthesis Example 1): Synthesis of a mixture of 1 EAP and 2 EAP A mixture of 1 EAP and 2 EAP (hereinafter referred to as “EAP mixture”) was synthesized according to the reaction formula shown in FIG. 1 (where 1 EAP and 2 EAP are respectively 2 (a) and 2 (b), both of which are one of the above-mentioned compounds (I).
Specifically, 19 g of 4-nitrophthalic anhydride (4-nitro-1,2-benzenecarboxylic anhydride) (hereinafter sometimes referred to as “4NPAH”), 120 ml of anhydrous ethyl alcohol, Was placed in a 200 ml flask (hereinafter referred to as “flask A”). In addition, 4NPAH used a special grade reagent of Tokyo Chemical Industry Co., Ltd., and anhydrous ethyl alcohol used a special grade reagent of Nacalai Tesque. A condenser (water cooling) and a heating device (specifically, an electric heater) were attached to Flask A, and Flask A was heated and refluxed at atmospheric pressure for 3 hours to cause a reaction (reaction 1 in FIG. 1). Thereafter, the flask A was allowed to cool to approximately room temperature.

The entire contents of the flask A were transferred to a hydrogenation reaction vessel (hereinafter referred to as “reaction vessel B”), and Pd / C (specifically, trade name “Palladium, 5 wt.% On, manufactured by Aldrich). "Activated carbon" was used.) 0.45 g of 5% (supported amount) powder was placed in the reaction vessel B as a hydrogenation catalyst, and the inside of the reaction vessel B was replaced with a hydrogen stream while stirring with a magnetic stirrer. For about 12 hours (overnight) (reaction 2 in FIG. 1).
The contents in the reaction vessel B were removed by filtration to remove catalyst Pd / C as a filtration residue, and the filtrate was recovered. The recovered filtrate was subjected to a rotary evaporator to remove residual ethyl alcohol and the like, and concentrated to obtain an oily substance (oil). The obtained oily substance was air-dried at room temperature (about 25 ° C.) for about 24 hours to obtain a concentrated oily substance.
The concentrated oily substance is a state in which fine solids are dispersed in a viscous liquid. In order to collect the fine solids, about 20 g of the concentrated oily substance is poured into 100 ml of distilled water, stirred, suspended in water and suspended. After preparing the liquid, the suspension was filtered using a filter paper to obtain a fine solid (hereinafter referred to as “crude solid”) as a filtration residue. The obtained crude solid was dried, and the mass of the dried crude solid was measured to be 11.5 g. The yield was 60.6% based on the weight of 19 g of 4NPAH used.

  The operation of Synthesis Example 1 will be briefly described with reference to FIG. First, 4NPAH and anhydrous ethyl alcohol are reacted by refluxing in flask A under atmospheric pressure for 3 hours to open a 5-membered ring containing 4NPAH oxygen atoms as shown in Reaction 1 in FIG. When ethyl alcohol is added, monoethyl nitrophthalate in FIG. 1 (note that the nitro group may exist in the para position as viewed from the carboxyl group bonded to the benzene ring or may exist in the meta position. ) Is formed in Flask A. The produced monoethyl nitrophthalate (hereinafter referred to as “ENP”) has two types of structural isomers depending on the position of the ethyl group and hydrogen atom derived from the added ethyl alcohol. Structural isomers coexist. Specifically, as seen from the nitro group added to the benzene ring of ENP, two types of structural isomers are generated depending on which carboxyl group at the meta position or para position is esterified with an ethyl group.

The contents of flask A (including the above-mentioned ENP) are transferred to reaction vessel B, Pd / C powder is placed in reaction vessel B as a hydrogenation catalyst, and the hydrogenation reaction is performed while replacing the reaction vessel B with a hydrogen stream. Thus, the EAP mixture of FIG. 1 in which the nitro group of ENP is reduced to an amino group by reaction 2 of FIG. 1 is formed.
Therefore, as described above, the catalyst Pd / C is removed from the contents in the reaction vessel B by filtration, and the filtrate is passed through a rotary evaporator to distill off the remaining ethyl alcohol and the like. The crude solid obtained by recovering the fine solid contained in the concentrated oily substance obtained by air drying at room temperature (about 25 ° C.) for about 24 hours has two structures of ENP described above. Two types of structural isomers corresponding to each isomer (the two types of isomers shown by (a) and (b) in FIG. 2) are included. Specifically, as seen from the amino group of the benzene ring of EAP, two types of structural isomers are produced depending on which carboxyl group of the meta position and the para position is esterified with the ethyl group. 2 in which the carboxyl group is esterified with an ethyl group ((a) in FIG. 2) is called “1EAP”, and the carboxyl group in the meta position is esterified with an ethyl group ((b) in FIG. 2) ) Is called “2EAP”.

(Separation Example 1): Separation of 1 EAP and 2 EAP As described above, the crude solid has two types of structural isomers corresponding to the two types of structural isomers of ENP ((a) and ( 2), the 1 EAP and 2EAP were separated and purified by recrystallization operation (crystallization operation) according to the steps of FIGS. 3 and 4 respectively.
First, 10 g of a crude solid was put into 80 ml of a mixed solvent, heated to about 80 ° C., stirred and dissolved (step 1 in FIG. 3), and then cooled to 20 ° C. at a cooling rate of about 1 ° C./hour ( Step 2) in FIG. Since a precipitate was generated in the cooled product, a first precipitate was obtained as a filtration residue by filtering the cooled product using a filter paper (step 3 in FIG. 3). In addition, as this mixed solvent, what mixed ethyl acetate and n-hexane by the volume ratio 5: 1 was used.

7 g of the first precipitate was put into 30 ml of ethyl acetate, heated and stirred to completely dissolve (step 4 in FIG. 3), and then cooled to 20 ° C. at a cooling rate of about 1 ° C./hour (FIG. 3). Step 5). Since precipitates were formed in the cooled product, a second precipitate (yellow) was obtained as a filtration residue by filtering the cooled product using a filter paper (step 6 in FIG. 3), and a filtrate (hereinafter referred to as “first” 2 filtrates "). The second precipitate was dried and weighed and found to be 3.0 g, and the yield was 42.8% based on 7 g of the first precipitate used.
The second filtrate was put on a rotary evaporator, and ethyl acetate was completely distilled off (step 7 in FIG. 3) to obtain a third precipitate. The third precipitate was dried under reduced pressure (Step 8 in FIG. 3) to obtain a dried third precipitate.

The dried third precipitate obtained by the operation shown in FIG. 3 was purified by the operation shown in FIG.
First, about 5 g of the dried third precipitate was put into 70 ml of distilled water, heated to 45 ° C. and stirred for about 1 hour (step 10 in FIG. 4) to obtain a third precipitate suspension. The third precipitate suspension was recovered as a filtration residue by filtration using a filter paper (step 11 in FIG. 4) to obtain 2.2 g of a fourth precipitate.
About 2 g of the fourth precipitate is put into 100 ml of toluene (special grade reagent), heated to about 120 ° C., dissolved by stirring (step 13 in FIG. 4), and then cooled at a cooling rate of about 2 ° C./hour. It was cooled to 0 ° C. (step 14 in FIG. 4). Since a precipitate was generated in the cooled product, a fifth precipitate (pale yellow) was obtained as a filtration residue by filtering the cooled product using a filter paper (step 15 in FIG. 4).
Similarly, about 1.7 g of the fifth precipitate is put into 90 ml of toluene (special grade reagent), heated to about 120 ° C., dissolved by stirring (step 16 in FIG. 4), and then about 2 ° C./hour. It cooled to 25 degreeC with the cooling rate (FIG. 4, step 17). Since a precipitate was generated in the cooled product, a sixth precipitate (white) was obtained as a filtration residue by filtering the cooled product using a filter paper (step 18 in FIG. 4).
Finally, about 1.3 g of the sixth precipitate is put into 90 ml of toluene (special grade reagent), heated to about 120 ° C., dissolved by stirring (step 19 in FIG. 4), and then about 2 ° C./hour. It cooled to 25 degreeC with the cooling rate (step 20 in FIG. 4). Since a precipitate was generated in the cooled product, a seventh precipitate (white) was obtained as a filtration residue by filtering the cooled product using a filter paper (step 21 in FIG. 4). When the seventh precipitate was dried and weighed, it was 0.65 g, and the yield was 13.0% with respect to about 5 g of the dried third precipitate used.

Three kinds of samples of the crude solid, the second precipitate, and the seventh precipitate obtained as described above were used in DSC (differential scanning calorimeter: Model TAC 7 / DX manufactured by Perkin Elmer). When melting | fusing point was measured, they were 110 degreeC (crude solid), 157 degreeC (2nd precipitate), and 174 degreeC (7th precipitate), respectively.
The DSC measurement conditions were a temperature increase rate of 20 ° C./min in a nitrogen atmosphere.

Chart obtained by spectroscopic analysis of three kinds of samples of these crude solid, second precipitate and seventh precipitate using an infrared spectrometer (model number FT / IR-410 manufactured by JASCO Corporation was used) Is shown in FIG. In FIG. 5, the horizontal axis represents the wave number (unit: cm ⁻¹ ), and the vertical axis represents the absorbance (Absorbance) (in the upward direction, the absorbance increases. “Au” in parentheses. . ”Means an arbitrary intensity. In FIG. 5, three graphs (A), (B), and (C) are drawn in the same coordinate system. However, when (B) is a crude solid sample, (B) is When the second precipitate is used as a sample, and (c) shows the case where the seventh precipitate is used as a sample. These (b) in FIG. 5 indicate that the second precipitate is 1 EAP, and (c) in FIG. 5 indicates that the seventh precipitate is 2 EAP. In FIG. 5, “Amino N—H stretching” is absorption based on N—H stretching vibration of a primary amine, and “COOH stretching” is absorption based on O—H stretching vibration of a carboxyl group, “CH ₂ , CH ₃ stretching” is absorption based on C—H stretching vibration of an ethyl group, and “Ether and Carboxylic acid (C═O) stretching” is C═O stretching vibration of an ester bond and a carboxyl group. Is based on absorption.
The measurement conditions of the infrared spectroscopic analysis were a measurement region of 4000 cm ^{-1 to} 500 cm ^-1 , a transmission mode, and a KBr tablet method.

Further, FIG. 6 shows a chart obtained by analyzing three types of samples of the crude solid, the second precipitate, and the seventh precipitate by proton ( ¹ H) nuclear magnetic resonance analysis (NMR). FIG. 6 is an analysis using model number JNM-AL300 manufactured by JEOL Ltd. The horizontal axis indicates the chemical shift (ppm) when TMS (tetramethylsilane) is used as the reference compound, and the vertical axis indicates A signal is shown. In FIG. 6, three graphs (a), (b) and (c) are drawn in the same coordinate system. However, when (b) is a crude solid sample, (b) When the second precipitate is used as a sample, and (c) shows the case where the seventh precipitate is used as a sample. On the other hand, FIG. 7 shows the structure of 1EAP in (a) and the structure of 2EAP in (b), and each hydrogen atom (proton) has a, b, c, d, e, f, a ', b', c ', d', e ', f' and their positions were indicated (the one with the prime "'" indicates 2EAP, and the one without it indicates 1EAP .)
The chemical shifts of the peaks shown in (b) and (c) of FIG. 6 and a, b, c, d, e, f, a ′, b ′ shown in (a) and (b) of FIG. , C ′, d ′, e ′, f ′, and the predicted chemical shifts of hydrogen atoms at positions c, d ′, e ′, f ′, a, b, c, As shown in d, e, f, a ′, b ′, c ′, d ′, e ′, and f ′, it became clear that each peak corresponds well with the hydrogen position of the structural formula shown in FIG. . From this, (b) in FIG. 6 indicates that the second precipitate is 1 EAP (FIG. 7 (a)), and (c) in FIG. 6 indicates that the seventh precipitate is 2EAP (FIG. 7 (b)). It was confirmed.

(Synthesis Example 2 and Separation Example 2): Synthesis and separation of 1HAP and 2HAP In place of 120 ml of anhydrous ethyl alcohol injected into Flask A in Synthesis Example 1 of 1EAP and 2EAP described above, this is a special reagent of Nacalai Tesque. 1-Hexyl 4-aminophthalate (FIG. 20) as shown in FIGS. 20 (a) and 20 (b) was obtained by using 114 ml of anhydrous 1-hexanol (hexyl alcohol) and performing the same experimental procedure as in Synthesis Example 1 and Separation Example 1 described above. (A), hereinafter referred to as “1HAP”) and 2-hexyl 4-aminophthalate (FIG. 20B, hereinafter referred to as “2HAP”) were synthesized and separated. Note that both 1HAP and 2HAP are one of the above-mentioned compounds (I).

(Example of polymerization)
Polymerization experiments were conducted using 1EAP, 2EAP and 2HAP obtained as described above.
FIG. 8 is a conceptual diagram (sectional view) showing the polymerization apparatus 11 used in the polymerization experiment. The polymerization apparatus 11 will be described with reference to FIG.
The polymerization apparatus 11 includes a three-necked flask 21, a heater 31 that heats the flask 21 under temperature control (a so-called mantle heater is used here), and an agitation inserted into the interior 23 of the flask 21. A vessel 41, a nitrogen introduction pipe 51 for introducing nitrogen gas into the interior 23 of the flask 21, and a gas outlet pipe 61 for deriving gas from the interior 23 of the flask 21.
The lower portion of the flask 21 is surrounded by the heating surface of the heater 31, and the heater 31 has an inner 23 temperature by a thermocouple thermometer (not shown) whose tip (detection end) has entered the solvent 13 in the inner 23. Is detected and the temperature is controlled. The heater 31 heats the flask 21 from the outer surface with an electric heater. After the switch 33 is turned on, the set temperature can be adjusted by operating the temperature adjustment knob 35 (in the set temperature display window 37). The set temperature is displayed.), The amount of heat generated is controlled so that the temperature detected by the thermocouple thermometer (not shown) (displayed in the current temperature display window 39) becomes the set temperature.
A stirring bar 43 having an upper end connected to a rotating device (not shown) is inserted into the largest mouth of the flask 21, and a stirring blade 45 is attached to the lower end of the stirring bar 43. The stirrer 41 is constituted by the stirring rod 43 and the stirring blade 45 rotated by the apparatus.
The other two ports of the flask 21 have a nitrogen introduction pipe 51 connected to a nitrogen gas supply device (not shown) for supplying nitrogen gas at a predetermined flow rate, and gas from the inside 23 of the flask 21 is led out. A gas outlet pipe 61 is attached so as to communicate with the inside 23. As a result, the atmosphere in the interior 23 of the flask 21 is always replaced by nitrogen gas introduced from the nitrogen introduction pipe 51 (this nitrogen gas replacement is generated when condensation polymerization is performed using 1EAP and / or 2EAP or 2HAP as a monomer. Ethyl alcohol and water are removed from the interior 23).

Polymerization was carried out using the polymerization apparatus 11 as described above in the following manner.
First, after injecting the solvent 13 (volume: V (ml)) into the flask 21 and assembling the polymerization apparatus 11 as shown in FIG. 8, the switch 33 of the heater 31 is turned on and the temperature control knob 35 is operated. Then, the solvent 13 is heated to a set temperature (the stirrer 41 is appropriately rotated by the rotating device, and the solvent 13 is heated while being stirred).
Second, when the solvent 13 is heated to the set temperature (the display of the current temperature display window 39 and the display of the set temperature display window 37 are substantially the same), the monomer powder (mass (g)) is added to the flask. (Introduction of the monomer powder into the interior 23 may be performed by temporarily removing the nitrogen introduction tube 51 from the mouth of the flask 21 and through the mouth.)
Third, after the charged monomer powder is completely dissolved in the solvent 13 (dissolution step), the rotation of the stirrer 41 by the rotating device is stopped and the stirring of the solvent 13 is stopped (the monomer powder in the second above). This state (precipitation step) is maintained until a predetermined reaction time elapses after the body is put into the flask 21 inside 23 (the solvent 13 is kept at the set temperature). In this holding state, the polyimide is precipitated as a fine solid (powder etc.) from the solution.
Fourthly, in the second step, when the monomer powder is put into the inside 23 of the flask 21 and a predetermined reaction time (6 hours) elapses, the contents existing in the inside 23 of the flask 21 are filtered. Since this filtration is performed near the set temperature, a glass fiber filter that can withstand such high temperatures (specifically, a model number “3GP5.5 cylindrical funnel type glass filter” manufactured by Shibata Kagaku Co., Ltd.) is used. Use.
Fifthly, the filtration residue obtained by the fourth filtration was sufficiently washed with n-hexane, further sufficiently washed with acetone, and sufficiently dried. This dried product is called “product”.
The predetermined reaction time is specifically 6 hours here.

FIG. 9 shows the results of the above polymerization experiment performed under various conditions.
Each item in FIG. 9 shows the following contents.
The “experiment number” is a number indicating each experimental operation.
“Monomer concentration” means that polyimide (polyimide having a repeating unit represented by the above formula (II)) is produced at a yield of 100% from the monomer powder charged in the inside 23 of the flask 21. The value obtained by dividing 100 by the value obtained by dividing the weight W (g) of the polyimide formed by (2) by the volume V (ml) of the solvent 13 (specifically, here, V = 20 ml) (( W / V) × 100) (unit: g / ml). Specifically, in Experiment No. 1 in FIG. 9, 1 EAP: 0.288 g was used, in Experiment No. 2 1 EAP: 0.577 g was used, and in Experiment No. 3 1 EAP: 0.577 g was used. 1 EAP: 0.577 g was used in Experiment No. 4, 1 EAP: 0.865 g was used in Experiment No. 5, 1 EAP: 1.442 g was used in Experiment No. 6, 1 EAP: 2.8835 g was used in Experiment No. 7, In Experiment No. 8, 1 EAP: 0.865 g was used, in Experiment No. 9, 1 EAP: 0.865 g was used, in Experiment No. 10, 1 EAP: 0.288 g was used, and in Experiment No. 11, 1 EAP: 0.260 g. A mixture of 2EAP: 0.028 g (0.288 g in total) was used, and in Experiment No. 12, 1 EAP: 0. 88g and 2EAP: using a mixture of 0.288g of (total 0.576 g), in Experiment No. 13 2EAP: Using 0.577 g, in Experiment No. 14 2HAP: Using 0.407 g. Taking Experiment No. 1 in FIG. 9 as an example, 0.288 g of 1EAP was used as described above, and this was multiplied by 145/209 (note that 145 is the molecular weight per repeating unit of polyimide, and 209 Is the molecular weight of 1 EAP.) Since W = 0.2 g, the monomer concentration ((W / V) × 100) = 1.0. Similar calculations can be made for other experiment numbers.
The “monomer ratio” is a molar ratio (%) between 1 EAP and 2 EAP in the mass (g) of the monomer powder charged into the inside 23 of the flask 21 (excluding the experiment number 14). If the number of moles of 1EAP is m1 (mole) and the number of moles of 2EAP is m2 (mole), it is represented by ((m1 / m2) × 100) (%) (that is, the monomer ratio is 100 Indicates that all of the monomer powder used is 1 EAP, and a monomer ratio of 0 indicates that all of the monomer powder used is 2 EAP.) In Experiment No. 14, all of the monomers used were 2HAP.
“Solvent used” is the type of solvent 13 used. “BT4” in FIG. 9 is a trade name “Barrel Therm 400” manufactured by Matsumura Oil Co., Ltd. Is a mixture of dibenzyltoluene, “DPS” is diphenyl sulfone manufactured by Tokyo Chemical Industry Co., Ltd., “LPF” is liquid paraffin manufactured by Nacalai Tesque, and “BT4 / LPF = 50/50” "Is a mixture of BT4 and LPF at 50 volume% (ie, half by volume).
The “set temperature” is a set temperature (unit: ° C.) set by the heater 31.
“Yield” means the weight W (g of polyimide produced when assuming that the monomer used produces polyimide (polyimide having a repeating unit represented by the above formula (II)) at a yield of 100%. ) (Since W (g) at the above monomer concentration is the same, please refer to the explanation at the above monomer concentration for the calculation method.) Ratio (100) of mass (g) of the obtained product to 100 It is doubled and converted to%.).
“Morphology” indicates the morphology observed when the obtained product is observed with a scanning electron microscope (SEM), and “Fibril” is fibrous (fine particle structure in which elongated strips are gathered). , “Cluster” indicates a lump shape, and “PN” indicates a fine particle shape having a crystal having a fibrous shape on the surface.
“10% weight loss temperature” means a temperature at which 10% weight is reduced from the weight at room temperature (25 ° C.) (ie, 90% of the weight at room temperature) when the temperature is raised by thermogravimetric analysis (TGA). (Unit: ° C.) Here, model number TGA7 manufactured by Perkin-Elmer was used as an analytical instrument, and the operating conditions were 20 ° C./min.

The product of Experiment No. 2 shown in FIG. 9 and the product of Experiment No. 13 shown in FIG. 9 are spectroscopically analyzed with an infrared spectrometer (model number FT / IR-410 manufactured by JASCO Corporation was used). The resulting chart is shown in FIG. In FIG. 10, the horizontal axis represents the wave number (unit: cm ^-1 ), and the vertical axis represents the absorbance (absorbance) (the absorbance increases in the upward direction. . ”Means an arbitrary intensity. In FIG. 10, two graphs (a) and (b) are drawn in the same coordinate system ((a) is shown at the top and (b) is shown at the bottom). These (a) are the cases where the product of experiment number 2 is used as a sample, and (b) is the case where the product of experiment number 13 is used as a sample. In FIG. 10, “Imid C═O stretching” is absorption based on C═O stretching vibration existing in the imide molecule (formula (II)), and “Imid C—N stretching” is an imide molecule (formula (II)) Absorption based on CN stretching vibrations. Figure 10 shows (a) and (b) none of the graphs, about a ^1720cm-1 and 1780cm ^over imide molecule specific C = O stretching vibration appearing at ^1, about 1380cm ^over the imide molecule specific appearing at ¹ C over N Stretching vibration was shown, and all the products showed that a polyimide having a repeating unit represented by the formula (II) was produced. In addition, when infrared spectroscopic analysis was performed in the same manner for other products, the same graphs as those of (a) and (b) were obtained, and both of the polyimides having a repeating unit represented by the formula (II) were obtained. It was shown that it was generated.
The measurement conditions of the infrared spectroscopic analysis were a measurement region of 4000 cm ^{-1 to} 500 cm ^-1 , a transmission mode, and a KBr tablet method.

The scanning electron micrograph of the product of experiment number 1 shown in FIG. 9 is shown in FIG. 11, the scanning electron micrograph of the product of experiment number 5 shown in FIG. 9 is shown in FIG. 12, and the experiment number shown in FIG. A scanning electron micrograph of the product No. 6 is shown in FIG. 13, a scanning electron micrograph of the product No. 11 shown in FIG. 9 is shown in FIG. 14, and the product No. 13 shown in FIG. FIG. 15 shows a scanning electron micrograph, FIG. 16 shows a scanning electron micrograph of the product of experiment number 4 shown in FIG. 9, and FIG. 15 shows a scanning electron micrograph of the product of experiment number 8 shown in FIG. A scanning electron micrograph of the product of experiment number 14 shown in FIG. 17 and shown in FIG. 9 is shown in FIG.
Each of these scanning electron micrographs (SEM) was a scanning electron microscope of model S-3500N manufactured by Hitachi High-Technologies Corporation, and the operating conditions were observed at an acceleration voltage of 20 KV.
Among these products, those described as “Fibril” in the form have the form of a fine particle structure in which elongated plate-like bodies (strips, ribbons) are gathered as shown in FIG. The cross-sectional shape perpendicular to the longitudinal direction (the direction along L in FIG. 18A) is substantially rectangular (cross-section hatching is omitted) as shown in FIG. 18B. Accordingly, here, the maximum dimension in the cross-sectional shape perpendicular to the longitudinal direction is the length of the diagonal of the substantially rectangular shape (dimension D in FIG. 18B).
Further, when the products of Experiment Nos. 2, 3, 7, 9 and 12 were similarly observed with a scanning electron microscope, these products were also in the form of an elongated plate similar to the forms of FIGS. 11 to 15 and FIG. It had the form of a fine particle structure in which bodies (band-like, ribbon-like) gathered. When the product of experiment number 10 was observed with a scanning electron microscope, it had an unclear (irregular) lump shape. When the products of Experiment Nos. 4 and 8 were observed with a scanning electron microscope, they had a fine particle form ("PN") having crystals in the form of fibers on the surface.

Further, FIG. 19 shows the results of wide-angle X-ray scattering (WAXS) measurement of the product of experiment number 2 shown in FIG. 9 and the product of experiment number 13 shown in FIG. Here, wide-angle X-ray scattering (WAXS) measurement uses a measuring device of the trade name “Mini Flex” manufactured by Rigaku Corporation, and operating conditions are a scan speed of 1 ° / min and a measurement region of 3 ° to 50 °. went. FIG. 19 is a graph in which the horizontal axis represents 2θ (unit: degree), and the vertical axis represents scattering intensity (arbitrary unit, where the upper direction is high). In FIG. 19, two graphs (a) and (b) are drawn in the same coordinate system ((a) is shown at the top and (b) is shown at the bottom). These (a) are the cases where the product of experiment number 2 is used as a sample, and (b) is the case where the product of experiment number 13 is used as a sample.
When other products other than the experiment number 10 were also subjected to wide angle X-ray scattering (WAXS) measurement, a graph similar to FIG. 19 was obtained.

  These Experiment Nos. 1-14 are examples, of which the product of Experiment No. 10 has an obscure (irregular) lumpy form and the products of Experiment Nos. 4 and 8 are fibers. It had a fine-grained form with crystals on the surface, but the other experiment numbers 1 to 3, 5 to 7, 9, and 11 to 14 were long and thin plate-like bodies (bands and ribbons). It had the form of a fine-grained structure.

  As shown in FIG. 9, the obtained product had a 10% weight loss temperature of 630 ° C. or more (here, since specific data is 635 ° C. to 721 ° C., about 635 ° C. to 720 ° C., measurement error) It is about 630 ° C. to 730 ° C. in consideration of the above and the like.

The products obtained in the experiment numbers 1 to 3, 5 to 7, 9, and 11 to 14 are all fine particle structures in which elongated strips (bands and ribbons) as shown in FIG. The form in FIG. 9 forms “Fibril”), and has a form in which a large number of the elongated plate-like bodies grow radially from a certain point. In addition, many things with a pointed tip part of the elongated plate-like body were observed.
As shown in FIGS. 11 to 17, the product obtained in the example does not change in form even when the monomer ratio is changed, and is generated by the ratio of 1 EAP to 2 EAP (molar ratio (%)). No change in product morphology was observed (1 EAP alone, 2 EAP alone, or a mixture of 1 EAP and 2 EAP, and no product morphological change was observed).
In the products obtained in the examples, when the monomer concentration was high, the density of the elongated plate-like objects inside the aggregate was increased, and the size of the aggregate was increased.
In any of the elongated plate-like products obtained in the examples, the dimension L along the longitudinal direction is very large (at least 5000 nm or more), and the substantially rectangular shape indicated by the cross-sectional shape perpendicular to the longitudinal direction. The dimension T in the short side direction was about 40 nm, and the dimension Y (width) in the long side direction of the substantially rectangular shape was about 130 nm to 140 nm. Accordingly, the maximum dimension in the cross-sectional shape perpendicular to the longitudinal direction is the length of the substantially rectangular diagonal line (dimension D in FIG. 18B), and is about 141 nm. A value (L / D) obtained by dividing a dimension along the longitudinal direction by a maximum dimension in a cross-sectional shape perpendicular to the longitudinal direction (L / D) is about 35, and a fine particle structure in which elongated strips are aggregated is formed. It was.
In addition, the products obtained in Experiment Nos. 1 to 3, 5 to 7, 9, and 11 to 14 are all fine particles in which elongated strips (bands and ribbons) as shown in FIG. Since the structure (the form in FIG. 9 is “Fibril”) is formed, if the polymerization reaction is performed at least under the following polymerization conditions (A) to (D), such an elongated strip (band, ribbon) It was clarified that a polyimide having a fine-grained structure in which is collected.
(A) Either one or a mixture of 1EAP and 2EAP (not affected by the “monomer ratio”) is used as a monomer, and these monomers are subjected to condensation polymerization. Alternatively, 2HAP may be used.
(B) Polymerization is carried out in “BT4”, that is, a solvent containing dibenzyltoluene (preferably containing 50% by volume or more of dibenzyltoluene in the solvent, see Experiment No. 9).
(C) Polymerization is carried out in the range of “monomer concentration” (((W / V) × 100) (unit: g / ml)) of 1.0 to 10.0.
(D) Polymerization is carried out at a polymerization temperature (set temperature) of 280 ° C to 330 ° C.

As shown in FIG. 19, in the products obtained in the examples, halo (wide peak) derived from amorphous (amorphous structure) was not observed in both (a) and (b). It became clear that it was crystalline.
The products obtained in the examples were insoluble even when immersed in concentrated sulfuric acid (specifically 97%) at room temperature (25 ° C.) for about 24 hours.
Further, the IR chart shown in FIG. 10 includes “Amino N-H stretching” (N of primary amine) indicated by (b) (1EAP) and (c) (2EAP) as seen in the IR chart shown in FIG. The absorption obtained based on the —H stretching vibration) and “COOH stretching” (absorption based on the O—H stretching vibration of the carboxyl group) and the like disappeared. Alternatively, it was revealed that 2EAP (2HAP in Experiment No. 14) is a polyimide having a repeating unit represented by the formula (II) produced by polymerization.

As mentioned above, the manufacturing method of the polyimide which has a repeating unit shown by the said Formula (II) shown to experiment number 1-14 is 1EAP which is the compound (I) shown by the said Formula (I), and / or 2EAP, 2HAP is polymerized in a solvent, and a polyimide having a repeating unit represented by the above formula (II) is precipitated as a solid.
In any of 1EAP, 2EAP and 2HAP, X3 in the above formula (I) is a hydrogen atom.
In 1EAP, X1 in X1 and X2 in the above formula (I) is a hydrogen atom, and X2 in formula (I) is an ethyl group.
In 2EAP, X2 in X1 and X2 in the above formula (I) is a hydrogen atom, and X1 in formula (I) is an ethyl group.

Moreover, the manufacturing method of the polyimide which has a repeating unit shown by the said formula (II) shown in experiment number 1-14 WHEREIN: All 1EAP and / or 2EAP (2HAP in experiment number 14) which are compounds (I) are the said. A dissolution step that completely dissolves in the solvent, and after the dissolution step (stirring is stopped), a precipitation step in which the polyimide having the repeating unit represented by the formula (II) is precipitated as a solid from the solution (the mixture is left without stirring) And deposited in a state).
Here, in any of Experiment Nos. 1 to 9 and 11 to 14, the solvent contains an aromatic compound (BT4: dibenzyltoluene, DPS: diphenylsulfone). And in any of experiment numbers 1-7, 9, 11-14, the aromatic compound is dibenzyltoluene. Furthermore, in any of Experiment Nos. 1 to 7 and 11 to 14, the solvent is dibenzyltoluene.

In any of Experiment Nos. 1 to 14, polymerization is performed in a temperature range of 240 ° C to 350 ° C.
And in experiment numbers 1-14, the polyimide which has a repeating unit shown by the said Formula (II) with a yield of 100% from the compound (I) (1EAP and / or 2EAP, 2HAP) used for superposition | polymerization produces | generates. Assuming that the weight W (g) of the polyimide produced is a ratio (percent) ((W / V) × 100) to the volume V of the solvent V (ml, here V = 20 ml) is 0.5 Or in the range of 12.0.
The products obtained in Experiment Nos. 1-3, 5-7, 9, 11-14 are all fine particles (powder) in which elongated strips (bands, ribbons) as shown in FIG. Shape).

It is a figure which shows synthetic | combination operation | movement of a monomer. It is a figure which shows the structural formula of 1EAP and 2EAP. It is a flowchart which shows separation operation of 1EAP and 2EAP. It is a flowchart which shows separation operation of 1EAP and 2EAP. It is an infrared-spectroscopy chart of a crude solid, a 2nd precipitate, and a 7th precipitate. The crude solid is a chart according to the protons of the second precipitate and seventh precipitate ^{(1 H)} nuclear magnetic resonance spectroscopy (NMR). It shows proton FIG 6 ⁽¹ H) nuclear magnetic resonance spectroscopy and (NMR) chart, and the hydrogen atom of 1EAP and 2EAP (protons), the correspondence relationship. It is a conceptual diagram (partial sectional view) showing a polymerization apparatus used in a polymerization experiment. It is a figure which shows the result of a polymerization experiment. It is an infrared spectroscopy chart of the product of experiment number 2 and the product of experiment number 13. It is a scanning electron micrograph of the product of experiment number 1. 6 is a scanning electron micrograph of the product of Experiment No. 5. It is a scanning electron micrograph of the product of experiment number 6. 2 is a scanning electron micrograph of the product of Experiment No. 11. It is a scanning electron micrograph of the product of experiment number 13. It is a scanning electron micrograph of the product of experiment number 4. It is a scanning electron micrograph of the product of experiment number 8. It is a schematic diagram explaining the form of the elongate plate-shaped body which a product has. It is a wide-angle X-ray-scattering (WAXS) measurement chart of the product of experiment number 2 and the product of experiment number 13. It is a figure which shows the structural formula of 1HAP and 2HAP. It is a scanning electron micrograph of the product of experiment number 14.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Polymerization apparatus 13 Solvent 21 Flask 23 Inside 31 Heater 33 Switch 35 Temperature control knob 37 Setting temperature display window 39 Current temperature display window 41 Stirrer 43 Stirring rod 45 Stirring blade 51 Nitrogen inlet pipe 61 Gas outlet pipe

Claims (12)

Compound (I) represented by Formula (I)
(In the formula, one of X1 and X2 is a hydrogen atom, the other means a hydrogen atom, an alkyl group, or an aryl group, and X3 means a hydrogen atom or an acyl group.)
Is produced in a solvent, and a polyimide having a repeating unit represented by the following formula (II) is precipitated as a solid.
  The manufacturing method of the polyimide of Claim 1 whose X3 in Formula (I) is a hydrogen atom.   The manufacturing method of the polyimide of Claim 1 or 2 whose said other one is a methyl group or an ethyl group among X1 and X2 in Formula (I). A dissolution step in which all of compound (I) is completely dissolved in the solvent;
A precipitation step in which the polyimide having the repeating unit represented by formula (II) is precipitated as a solid from the solution after the dissolution step;
The manufacturing method of the polyimide of any one of Claims 1 thru | or 3 containing this.   The manufacturing method of the polyimide of Claim 4 whose said solvent contains an aromatic compound.   The aromatic compound is a mixture of one or more selected from the group consisting of diisopropylnaphthalene, diethylnaphthalene, ethyl-isopropylnaphthalene, cyclohexyldiphenyl, diethylbiphenyl, triethylbiphenyl, and dibenzyltoluene. The manufacturing method of polyimide.   The method for producing a polyimide according to claim 6, wherein the solvent is dibenzyltoluene.   The method for producing a polyimide according to any one of claims 1 to 7, wherein the polymerization is performed in a temperature range of 240 ° C to 350 ° C.   The weight W (g) of the polyimide produced when assuming that the polyimide having the repeating unit represented by the formula (II) is produced at a yield of 100% from the compound (I) used for the polymerization is the solvent. The method for producing a polyimide according to any one of claims 1 to 8, wherein a ratio (percent) to (v / ml) of volume ((W / V) x 100) is in a range of 0.5 to 12.0. .   The method for producing a polyimide according to any one of claims 1 to 9, wherein the polyimide to be formed forms a fine particle structure in which elongated strips are aggregated.   The polyimide which can be obtained by the manufacturing method of the polyimide of any one of Claims 1 thru | or 10. A polyimide having a fine particle structure having a repeating unit represented by the following formula (II) and in which elongated strips are assembled.