JP4896900B2 - Manufacturing method of fiber molded body made of rigid heterocyclic polymer - Google Patents

Description

  The present invention relates to a method for producing a high molecular weight rigid heterocyclic polymer fiber molding.

A polybenzoazole fiber represented by polybenzobisoxazole is a molded fiber having excellent tensile strength and heat resistance. There are extensive examples of polymerization and spinning methods for polybenzobisoxazole compounds. In general, diaminoresorcinol and its derivatives, and aromatic dicarboxylic acid derivatives are superheated in polyphosphoric acid and the polymer dope obtained is obtained. As such, a fiber molded body is obtained by a conventionally known dry jet wet spinning. At this time, as a problem in the process, in order to obtain a fiber having excellent tensile properties, it is necessary to produce a high molecular weight polymer. However, polybenzobisoxazole increases the molecular weight because of its rigid structure. Thus, the polymer dope obtained has a very high viscosity, and a special device is required for stirring, and a spinning device compatible with the high viscosity dope is also required in the spinning process.
WO85 / 04178 pamphlet

  An object of this invention is to provide the manufacturing method of a high molecular weight rigid type heterocyclic heterocyclic fiber molded object.

（ｎは１〜４の整数、ＸはＯ、Ｓ、ＮＨいずれかを表し、Ａｒ^１は炭素数４〜２０の４価の芳香族基を表し、Ａｒ^２は炭素数６〜２０の少なくとも１〜４個のヒドロキシを有する２価の芳香族基を表す。）
で表わされる繰り返し単位、及び下記式（Ｃ）及びまたは（Ｄ）

（ＸはＯ、Ｓ、ＮＨいずれかを表しＡｒ^１は炭素数４〜２０の４価の芳香族基を表わし，ＹはＮ、ＣＨのいずれかを表す。）
で表わされる繰り返し単位とからなり、下記式（１）
０．１≦（ａ＋ｂ）／（ｃ＋ｄ）≦１０．０ （１）
（ａは上記式（Ａ）のモル数を表し、ｂは上記式（Ｂ）のモル数を表し、ｃは上記式（Ｃ）のモル数を表し、ｄは上記式（Ｄ）のモル数を表す。）
を満たす剛直系複素環高分子からなり、
０．０３ｇ／１００ｍｌの濃度のメタンスルホン酸溶液で２５℃にて測定した特有粘度が５．０〜１５ｄｌ／ｇである繊維成型体(Ｉ)を得た後、１００〜２５０℃にて１〜５０時間加熱することを特徴とする、
特有粘度が１３〜３０ｄｌ／ｇの剛直系複素環高分子繊維成型体(II)の製造方法である。 The present invention provides the following formulas (A) and / or (B)

(N represents an integer of 1 to 4, X represents one of O, S, and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and Ar ² represents at least 1 having 6 to 20 carbon atoms. Represents a divalent aromatic group having ~ 4 hydroxys)
A repeating unit represented by formula (C) and / or (D):

(X represents any of O, S and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and Y represents either N or CH.)
The repeating unit represented by the following formula (1)
0.1 ≦ (a + b) / (c + d) ≦ 10.0 (1)
(A represents the number of moles of the above formula (A), b represents the number of moles of the above formula (B), c represents the number of moles of the above formula (C), and d represents the number of moles of the above formula (D). Represents.)
Consisting of a rigid heterocyclic polymer satisfying
After obtaining a fiber molded body (I) having a specific viscosity of 5.0 to 15 dl / g measured at 25 ° C. with a methanesulfonic acid solution having a concentration of 0.03 g / 100 ml, 1 to 100 to 250 ° C. It is characterized by heating for 50 hours,
This is a method for producing a rigid heterocyclic polymer fiber molded body (II) having a specific viscosity of 13 to 30 dl / g.

  According to the present invention, a high-molecular-weight fiber molded body can be provided, and the obtained fiber molded body has better fiber properties.

（ｎは１〜４の整数、ＸはＯ、Ｓ、ＮＨいずれかを表し、Ａｒ^１は炭素数４〜２０の４価の芳香族基を表し、Ａｒ^２は炭素数６〜２０の少なくとも１〜４個のヒドロキシを有する２価の芳香族基を表す。）
で表わされる繰り返し単位、及び下記式（Ｃ）及びまたは（Ｄ）

（ＸはＯ、Ｓ、ＮＨいずれかを表しＡｒ^１は炭素数４〜２０の４価の芳香族基を表わし，ＹはＮ、ＣＨのいずれかを表す。）
で表わされる繰り返し単位とからなり、下記式（１）
０．１≦（ａ＋ｂ）／（ｃ＋ｄ）≦１０．０ （１）
（ａは上記式（Ａ）のモル数を表し、ｂは上記式（Ｂ）のモル数を表し、ｃは上記式（Ｃ）のモル数を表し、ｄは上記式（Ｄ）のモル数を表す。）
を満たす剛直系複素環高分子からなる。 <Rigid heterocyclic polymer fiber molding (II)>
The rigid heterocyclic polymer fiber molded body (II) obtained in the present invention has the following formulas (A) and / or (B):

(N represents an integer of 1 to 4, X represents one of O, S, and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and Ar ² represents at least 1 having 6 to 20 carbon atoms. Represents a divalent aromatic group having ~ 4 hydroxys)
A repeating unit represented by formula (C) and / or (D):

(X represents any of O, S and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and Y represents either N or CH.)
The repeating unit represented by the following formula (1)
0.1 ≦ (a + b) / (c + d) ≦ 10.0 (1)
(A represents the number of moles of the above formula (A), b represents the number of moles of the above formula (B), c represents the number of moles of the above formula (C), and d represents the number of moles of the above formula (D). Represents.)
It consists of a rigid heterocyclic polymer that satisfies

  The rigid heterocyclic polymer fiber molding (II) is made of a rigid heterocyclic polymer having a specific viscosity of 13 to 30 dl / g measured at 25 ° C. with a methanesulfonic acid solution having a concentration of 0.5 g / 100 ml. This is a fiber molded body.

  The rigid heterocyclic polymer fiber molding (II) has a specific viscosity of 5.0 to 5 measured at 25 ° C. with a methanesulfonic acid solution having a concentration of 0.03 g / 100 ml made of the same rigid heterocyclic polymer. After obtaining a fiber molded body (I) of 15 dl / g, it is obtained by heating at 100 to 250 ° C. for 1 to 50 hours.

  As heat treatment conditions at this time, it is preferable to use an inert gas such as nitrogen or argon, or under reduced pressure. The heating temperature is 100 ° C. to 250 ° C., although depending on the heating time, 120 ° C. to 200 ° C. is preferable, and 140 ° C. to 180 ° C. is more preferable. When the heating temperature is lower than 100 ° C., a predetermined effect cannot be obtained. When the heating temperature is higher than 250 ° C., there is a problem such as decomposition of the molded body. The heating time is 1 to 50 hours, preferably 5 to 40 hours, more preferably 10 to 30 hours, depending on the temperature conditions. When the heating time is shorter than 1 hour, a predetermined effect cannot be obtained, and when it is longer than 50 hours, there is a problem such as decomposition of the molded body.

  In the above formula (1), when (a + b) / (c + d) is smaller than 0.1 or larger than 10.0, a predetermined effect cannot be obtained. The lower limit of (a + b) / (c + d) is preferably 0.11 or more, more preferably 0.125 or more, and further preferably 0.15 or more. Moreover, as an upper limit of (a + b) / (c + d), 9.0 or less is preferable, More preferably, it is 8.0 or less, More preferably, it is 7.0 or less. Therefore, the optimum range of (a + b) / (c + d) in the present invention can be said to be 0.15 ≦ g / h ≦ 7.0.

In the above formulas (A) to (D), Ar ¹ is a tetravalent aromatic group having 4 to 20 carbon atoms, and may contain 1 to 2 nitrogen atoms.

  In the ratio of the number of moles a in the above formula (A) and the number of moles b in the above formula (B), X is substantially indistinguishable, but when X is O or S, a is 80% or more. Preferably, it is preferably close to 100%. In the ratio of the number of moles c in the above formula (C) and the number of moles d in the above formula (D), X is substantially indistinguishable, but when X is O or S, d is 80% or more of the total. Preferably, it is preferably close to 100%.

  In the above formulas (A), (B), (C), (D), X represents any one of O, S, and NH, and is preferably selected from any one of S and O. In the above formulas (C) and (D), Y is selected from either N or CH.

（ＸはＯ、Ｓ、ＮＨいずれかを表し、Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表わされる繰り返し単位が挙げられる。 Of the above formulas (A), the following formula (A-1) is preferred.

(X represents any of O, S, and NH, and Z ¹ and Z ² represent either N or CH.)
The repeating unit represented by these is mentioned.

（ＸはＯ、Ｓ、ＮＨいずれかを表し、Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表わされる繰り返し単位が挙げられる。 Of the above formulas (B), the following formula (B-1) is preferred.

(X represents any of O, S, and NH, and Z ¹ and Z ² represent either N or CH.)
The repeating unit represented by these is mentioned.

（ＸはＯ、Ｓ、ＮＨいずれかを表し、Ｙ、Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表わされる繰り返し単位が挙げられる。 Among the above formulas (C), the following formula (C-1) is preferable.

(X represents any of O, S and NH, and Y, Z ¹ and Z ² represent either N or CH.)
The repeating unit represented by these is mentioned.

（ＸはＯ、Ｓ、ＮＨいずれかを表し、Ｙ、Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表わされる繰り返し単位が挙げられる。 Of the above formulas (D), the following formula (D-1) is preferred.

(X represents any of O, S and NH, and Y, Z ¹ and Z ² represent either N or CH.)
The repeating unit represented by these is mentioned.

で表わされる繰り返し単位が挙げられる。 Among the above formula (A), the following formula (A-2) is more preferable.

The repeating unit represented by these is mentioned.

で表わされる繰り返し単位が挙げられる。 Among the above formulas (C), the following formula (C-2) is preferable.

The repeating unit represented by these is mentioned.

  The rigid heterocyclic polymer can be variously modified by adding various secondary additives as required. Examples of secondary additives include stabilizers, antioxidants, UV absorbers, pigments, colorants, various fillers, electrostatic agents, mold release agents, plasticizers, fragrances, antibacterial and antifungal agents, nucleation And other similar agents such as agents, lubricants, flame retardants, foaming agents, fillers and the like.

(About manufacturing method of rigid heterocyclic polymers)
The rigid heterocyclic polymer in the present invention can be industrially produced with good productivity by the following method.

（ＸはＯ、Ｓ、ＮＨいずれかを表し、Ａｒ^１は炭素数４〜２０の４価の芳香族基を表わし、また（Ｅ）、（Ｆ）は塩酸塩でも構わない。）
で表わされる芳香族アミン誘導体およびその塩酸塩からなる群から選択される少なくとも１種と、下記式（Ｇ）または（Ｈ）

（Ｒ^１，Ｒ^１’、Ｒ^２、Ｒ^２’は各々独立に水素あるいは炭素数６〜２０の芳香族基を表す。）
で表わされる芳香族ジカルボン酸誘導体の少なくとも１種を反応させる方法が挙げられる。 That is, the following formula (E) or (F)

(X represents any of O, S and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and (E) and (F) may be hydrochlorides.)
At least one selected from the group consisting of an aromatic amine derivative represented by the following formula and hydrochloride thereof, and the following formula (G) or (H):

(R ¹ , R ¹ ′, R ² , and R ^{2 ′} each independently represent hydrogen or an aromatic group having 6 to 20 carbon atoms.)
And a method of reacting at least one aromatic dicarboxylic acid derivative represented by the formula:

Ar ¹ in the above formulas (E) and (F) is the same as Ar ¹ described for the composition of the wholly aromatic azole, and R ¹ , R ¹ ′, R ^{2 in the} general formulas (G) and (H). , R ^{2 ′} each independently represents hydrogen or a monovalent aromatic group having 6 to 20 carbon atoms, and specific examples of the aromatic group include a phenylene group, a naphthalene group, a biphenylene group, an isopropylidene diphenyl group, a diphenyl ether group, A diphenyl sulfide group, a diphenyl sulfone group, a diphenyl ketone group, and the like. One or more hydrogen atoms of these aromatic groups are each independently a halogen group such as fluorine, chlorine or bromine; an alkyl group having 1 to 6 carbon atoms such as a methyl group, an ethyl group, a propyl group or a hexyl group; It may be substituted with a C5-C10 cycloalkyl group such as a cyclopentyl group or a cyclohexyl group; an alkoxycarbonyl group such as a methoxycarbonyl group or an ethoxycarbonyl group.

（Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表される芳香族アミン誘導体あるいはその２塩酸塩、及びまたは下記式

（Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表される芳香族アミン誘導体あるいはその２塩酸塩であることが好ましい。 The aromatic amine derivative represented by the above formula (E) is represented by the following formula:

(Z ¹ and Z ² represent N or CH.)
An aromatic amine derivative represented by the formula:

(Z ¹ and Z ² represent N or CH.)
It is preferable that it is the aromatic amine derivative represented by these, or its dihydrochloride.

（Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表される芳香族アミン誘導体あるいはその２塩酸塩、及びまたは下記式

（Ｚ^１、Ｚ^２はＮ、ＣＨのいずれかを表す。）
で表される芳香族アミン誘導体あるいはその２塩酸塩であることが好ましい。 The aromatic amine derivative represented by the above formula (F) is represented by the following formula:

(Z ¹ and Z ² represent N or CH.)
An aromatic amine derivative represented by the formula:

(Z ¹ and Z ² represent N or CH.)
It is preferable that it is the aromatic amine derivative represented by these, or its dihydrochloride.

で表される芳香族アミン誘導体あるいはその２塩酸塩であり、（Ｇ）が下記式

で表わされる芳香族ジカルボン酸誘導体であり、（Ｈ）が下記式

で表わされる芳香族ジカルボン酸誘導体であることが好ましい。 Among them, the aromatic amine derivative represented by the above formula (E) is represented by the following formula:

(G) is represented by the following formula:

An aromatic dicarboxylic acid derivative represented by the formula (H):

It is preferable that it is an aromatic dicarboxylic acid derivative represented by.

The number of moles of each monomer (reaction component) is the above formula (1)
Following formula (2), (3)
0.8 ≦ (e + f) / (g + h) ≦ 1.2 (2)
0.1 ≦ g / h ≦ 10.0 (3)
(E is an aromatic amine derivative represented by the above formula (E), f is an aromatic amine derivative represented by the above formula (F), g is an aromatic dicarboxylic acid derivative represented by the above formula (G), h is the number of moles of each charged aromatic dicarboxylic acid derivative represented by the above formula (H).
Are preferably satisfied simultaneously.

  When (e + f) / (g + h) is smaller than 0.8 or larger than 1.2, it may be difficult to obtain a polymer having a sufficient degree of polymerization. The lower limit of (e + f) / (g + h) is preferably 0.9 or more, more preferably 0.93 or more, and still more preferably 0.95 or more. Moreover, as an upper limit of (e + f) / (g + h), 1.1 or less is preferable, More preferably, it is 1.07 or less, More preferably, it is 1.05 or less. Therefore, the optimum range of (e + f) / (g + h) in the present invention can be 0.95 ≦ (e + f) / (g + h) ≦ 1.05.

When g / h is smaller than 0.1 or larger than 10.0, a predetermined effect cannot be obtained. The lower limit of g / h is preferably 0.11 or more, more preferably 0.125 or more, and further preferably 0.15 or more. Moreover, as an upper limit of g / h, 9.0 or less is preferable, More preferably, it is 8.0 or less, More preferably, it is 7.0 or less. Therefore, it can be said that the optimum range of g / h in the present invention is 0.15 ≦ g / h ≦ 7.0.
(E) and (F) may be used alone or in combination, and the molar ratio of (E) :( F) can be appropriately selected at an arbitrary ratio of 0: 100 to 100: 0.

  For the reaction, either a reaction performed in a solvent or a solvent-free heating and melting reaction can be employed. For example, it is preferable to carry out a heating reaction in a reaction solvent described later with stirring. The reaction temperature is preferably 50 ° C to 500 ° C, more preferably 100 ° C to 350 ° C. This is because if the temperature is lower than 50 ° C., the reaction hardly proceeds, and if the temperature is higher than 500 ° C., side reactions such as decomposition tend to occur. Although the reaction time depends on temperature conditions, it is usually 1 hour to several tens of hours. The reaction can be carried out under pressure or under reduced pressure.

  The reaction usually proceeds even without a catalyst, but a transesterification catalyst may be used if necessary. Examples of transesterification catalysts used in the present invention include antimony compounds such as antimony trioxide, stannous acetate, tin chloride, tin octylate, tin compounds such as dibutyltin oxide and dibutyltin diacetate, and alkaline earth metal salts such as calcium acetate. And phosphorous acid such as alkali metal salts such as sodium carbonate and potassium carbonate, diphenyl phosphite and triphenyl phosphite.

  In the reaction, a solvent can be used as necessary. Preferred solvents include 1-methyl-2-pyrrolidone, 1-cyclohexyl-2-pyrrolidone, dimethylacetamide, dimethyl sulfoxide, diphenyl ether, diphenyl sulfone, dichloromethane, chloroform, tetrahydrofuran, o-cresol, m-cresol, p-cresol, Although phosphoric acid, polyphosphoric acid, etc. can be mentioned, it is not limited to this.

In order to prevent decomposition and coloring of the rigid heterocyclic polymer, the reaction is desirably performed in a dry inert gas atmosphere.
The rigid heterocyclic polymer thus produced has a specific viscosity in the range of 5.0 to 15 as measured at 25 ° C. with a methanesulfonic acid solution having a concentration of 0.03 g / 100 ml. .

  As a method for producing a rigid heterocyclic polymer, one of the following two methods is preferably used. That is: 1. a method of polymerizing (A) or (B) and (C) or (D) simultaneously; In this method, (A) or (B) and (C) or (D) are individually polymerized to obtain a polymer and then kneaded.

  When using the method 2 described above, the polymer obtained by the above means can be kneaded by a conventionally known method, and a conventionally known kneading apparatus such as a single screw ruder, a twin screw ruder, or a homogenizer is used. I can do it. The kneading method may be either between polymers or between polymer dopes.

(Fiber molding method)
As a method for producing the fiber molded body (I), known techniques such as wet spinning and dry jet spinning can be preferably used. In molding, the polymer obtained by the polymerization method described above can be dissolved in a solvent to form a polymer dope, or a reaction solution obtained by solution polymerization can be used as it is as a polymer dope.

EXAMPLES Hereinafter, although an Example demonstrates this invention further more concretely, this invention is not limited at all by these. In addition, each measured value in the following examples is a value obtained by the following method.
(1) [Specific viscosity]
It is a value obtained by the following formula based on the relative viscosity (η _rel ) measured at 30 ° C. using methanesulfonic acid at a polymer concentration of 0.03 g / dl.
η _inh = (lnη _rel ) / C
(Η _inh is the specific viscosity, η _rel is the relative viscosity, and C is the concentration)
(2) Mechanical properties: Tensile strength universal testing machine 1225A manufactured by Orientec Co., Ltd. was used to determine tensile strength and Young's modulus.

[Reference Example 1] (Synthesis and polymerization of monomer) (N-PBO)
7 parts by weight of 4,6-diamino-1,3-benzenediol dihydrochloride was dissolved in 33 parts by weight of water deaerated with nitrogen. 5.347 parts by weight of pyridinedicarboxylic acid was dissolved in 64 parts by weight of 1M aqueous sodium hydroxide solution and degassed with nitrogen. An aqueous solution of 4,6-diamino-1,3-benzenediol dihydrochloride is dropped into an aqueous solution of disodium pyridinedicarboxylic acid over 10 minutes, and 4,6-diamino-1,3-benzenediol / pyridinedicarboxylate is added. Of white precipitate formed. At this time, the reaction temperature was maintained at 90 ° C. The obtained salt was filtered, dispersed and mixed in 3000 parts by weight of water deaerated with nitrogen, and filtered again. This dispersion mixing and filtration operation was repeated three times.

[Reference Example 2] (Synthesis of monomer) (OH-PBO)
7 parts by weight of 4,6-diamino-1,3-benzenediol dihydrochloride was dissolved in 33 parts by weight of water deaerated with nitrogen. 6.180 parts by weight of 2,5-dihydroxyterephthalic acid was dissolved in 64 parts by weight of 1M aqueous sodium hydroxide solution and degassed with nitrogen. An aqueous solution of 4,6-diamino-1,3-benzenediol dihydrochloride is dropped into an aqueous solution of disodium salt of 2,5-dihydroxyterephthalate over 10 minutes, and 4,6-diamino-1,3-benzenediol / A white precipitate of 2,5-dihydroxyterephthalate was formed. At this time, the reaction temperature was maintained at 90 ° C. The obtained salt was filtered, dispersed and mixed in 3000 parts by weight of water deaerated with nitrogen, and filtered again. This dispersion mixing and filtration operation was repeated three times.

[Reference Example 3] (Polymerization) (Copolymerization of OH-PBO / N-PBO)
34.9094 parts by weight of pyridinedicarboxylate of 4,6-diamino-1,3-benzenediol obtained in Reference Example 1 and 4,6-diamino-1,3-benzenediol obtained in Reference Example 2 In addition, 173.2 parts by weight of polyphosphoric acid and 60 parts by weight of phosphorus pentoxide and 0.4 parts by weight of tin chloride were added to 19.2133 parts by weight of 2,5-dihydroxyterephthalate of No. 5 and stirred and mixed at 80 ° C. for 2 hours. Thereafter, the temperature was raised to 170 ° C. over 6 hours, followed by stirring at 170 ° C. for 50 hours to complete the reaction.

[Reference Example 4] Production of Fiber Molded Body (I) The polymer dope obtained in Reference Example 3 was used with a cap having a pore diameter of 90 μmm and a number of holes of 20 and the doping temperature was kept at 180 ° C., 4.6 / min. And extruded into a coagulation bath of ion exchange water. The distance between the cap surface and the coagulation bath was 20 cm. The extruded fiber was wound on a stainless steel bobbin at 40 m / min and washed with water to obtain a filament. Table 1 shows the physical properties of the filaments obtained.

[Example 1]
While the fiber obtained in Reference Example 4 was wound on a bobbin, heat treatment was performed at 150 ° C. for 24 hours in a reduced pressure dryer under a nitrogen atmosphere at 1 mmHg. The specific viscosity of the obtained fiber is 14.1, and the physical properties of the obtained filament are shown in Table 1.

Claims (6)

The following formula (A) and / or (B)

(N represents an integer of 1 to 4, X represents one of O, S, and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and Ar ² represents at least 1 having 6 to 20 carbon atoms. Represents a divalent aromatic group having ~ 4 hydroxys)
A repeating unit represented by formula (C) and / or (D):

(X represents any of O, S and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and Y represents either N or CH.)
The repeating unit represented by the following formula (1)
0.1 ≦ (a + b) / (c + d) ≦ 10.0 (1)
(A represents the number of moles of the above formula (A), b represents the number of moles of the above formula (B), c represents the number of moles of the above formula (C), and d represents the number of moles of the above formula (D). Represents.)
Consisting of a rigid heterocyclic polymer satisfying
After obtaining a fiber molded body (I) having a specific viscosity of 5.0 to 15 dl / g measured at 25 ° C. with a methanesulfonic acid solution having a concentration of 0.03 g / 100 ml, 1 to 100 to 250 ° C. It is characterized by heating for 50 hours,
A method for producing a rigid heterocyclic polymer fiber molding (II) having a specific viscosity of 13 to 30 dl / g. The above formula (A) is the following formula (A-1)

(X represents O, S, NH, and Z ¹ and Z ² represent N or CH.)
And the above formula (C) is represented by the following formula (C-1):

(X represents any of O, S and NH, and Y, Z ¹ and Z ² represent either N or CH.)
The method for producing a fiber molded body (II) according to claim 1, wherein the unit is a repeating unit represented by formula (1). The above formula (A) is the following formula (A-2)

And the above formula (C) is represented by the following formula (C-2):

The method for producing a fiber molded body (II) according to claim 1, wherein the unit is a repeating unit represented by formula (1). The following formula (E) or (F)

(X represents any of O, S and NH, Ar ¹ represents a tetravalent aromatic group having 4 to 20 carbon atoms, and (E) and (F) may be hydrochlorides.)
At least one selected from the group consisting of an aromatic amine derivative represented by the following formula and hydrochloride thereof, and the following formula (G) or (H):

(R ¹ , R ¹ ′ R ² and R ² ′ each independently represent hydrogen or an aromatic group having 6 to 20 carbon atoms.)
At least one aromatic dicarboxylic acid derivative represented by:
The following formulas (2) and (3)
0.8 ≦ (e + f) / (g + h) ≦ 1.2 (2)
0.1 ≦ g / h ≦ 10.0 (3)
(E is an aromatic amine derivative represented by the above formula (E), f is an aromatic amine derivative represented by the above formula (F), g is an aromatic dicarboxylic acid derivative represented by the above formula (G), h is the number of moles of each charged aromatic dicarboxylic acid derivative represented by the above formula (H).
The fiber molded body (II) according to claim 1, wherein the fiber molded body (I) having a specific viscosity of 5.0 to 15 dl / g is obtained by reacting at a ratio satisfying Production method. The aromatic amine derivative represented by the above formula (E) is represented by the following formula:

(Z ¹ and Z ² represent N or CH.)
An aromatic amine derivative represented by the formula:

(Z ¹ and Z ² represent N or CH.)
The method for producing a fiber molded body (II) according to claim 4, wherein the aromatic amine derivative is represented by the following formula: The aromatic amine derivative represented by the above formula (E) is represented by the following formula:

(G) is represented by the following formula:

And (H) is represented by the following formula:

The method for producing a fiber molded body (II) according to claim 4, which is an aromatic dicarboxylic acid derivative represented by the formula: