JPH0674325B2 - Method for producing polyarylene sulfides - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a process for the preparation of optionally branched polyarylene sulfides from alkali metal sulfides and aromatic halides in a polar solvent, characterized in that 0.2 to 100 mole percent of an amino acid, based on the aromatic dihalide, is added to the reaction mixture.

Polyarylene sulfides and methods for their preparation are known (e.g., U.S. Pat. Nos. 2,513,188; 3,117,620; 3,
No. 354,129; No. 3,524,835; No. 3,790,536; No. 3,839,301; 4,0
No. 48,259; No. 4,038,260; No. 4,038,261; No. 4,038,262; 4,05
Nos. 6,515; 4,060,520; 4,064,114; 4,287,347 and 4,1
16,947; German Patent Publication Nos. 2,453,485 and 2,453,749
No. and German Patent Publication Nos. 2,623,362; 2,623,333; 2,
No. 930,797; No. 2,930,710; No. 3,019,732; No. 3,030,488; 3,19
(See No. 0,538).

Many of these documents describe the addition of inorganic or organic salts to the reaction mixture in order to decrease the melt flow of the resulting polyphenylene sulfide, i.e., to increase the melt viscosity.
For example, it can be thermoplastically processed into injection moldings, films, and fibers only if its melt viscosity is sufficiently high. Without the addition of the above salts, the resulting polyphenylene sulfide can only achieve the required low melt flow by a separate, additional post-condensation or curing step.

The salts used in the above documents are, for example, alkali metal carbonates (German Patent Publication No. 2,453,749), lithium halides or alkali metal carbonates (German Patent Publication No. 2,623,362), lithium chloride or lithium carbonate (German Patent Publication No. 2,623,363); alkali metal carbonates in combination with alkali metal carbonates (U.S. Pat. No. 4,033,499);
8,259), lithium acetate (German Patent Publication No. 2,623,333
No. 2,930,710), trialkali metal phosphate (German Patent Publication No. 2,930,710)
0), trialkali metal phosphate (German Patent Publication No. 2,930,7
97), alkali metal fluorides (German Patent Publication No. 3,01
9,732), alkali metal sulfonates (U.S. Pat. No. 4,000,000;
38,260), lithium carbonate, and lithium borate (U.S. Pat. No. 4,030,518).

In addition, it is known from German Offenlegungsschrift 3,120,538 that polyarylene sulfides having a high melt viscosity can be obtained by adding N,N-dialkylcarboxylic acid amides to the reaction mixture.

The use of polar solvents for the preparation of polyarylene sulfides is also described therein.

Here, the reaction in a polar solvent, preferably an N-alkyl lactam, in the presence of an amino acid, preferably an aliphatic amino acid, directly, i.e., without the need for a separate curing step,
It has been found that this leads to polyarylene sulfides that can be thermoplastically processed.

Thus, the present invention provides a compound comprising (a) 50 to 100 mole % of a compound of the following general formula: and 0 to 50 mol % of an aromatic dihalogen compound corresponding to the following general formula: in which X represents a halogen atom, such as chlorine or bromine, in the meta- or para-position relative to one another; and R ¹ , which may be the same or different, is hydrogen, C ₁ -
_C4 alkyl, _C5 - _C10 cycloalkyl, _C6 - _C10 aryl, _C7 - _C10 alkylaryl, _C7 - _C14 arylalkyl, and in addition, two ^R1 groups in the ortho-position relative to each other may combine to form an aromatic or heterocyclic ring containing up to three heteroatoms, such as N, O and S, and one of the ^R1 groups is always different from hydrogen; and (b) 0 to 5 mol %, preferably 0.1 to 2.5 mol %, based on the total of the aromatic dihalogen compounds (I) and (II).
(c) an aromatic trihalogen or tetrahalogen compound corresponding to the following general formula ArXn (III), in which Ar represents an aromatic _C6 - _C14 group or a heterocyclic group in which up to three ring carbon atoms can be replaced by heteroatoms, such as N, O, and S; X represents a halogen, such as chlorine or bromine; and n represents the number 3 or 4; and (c) an alkali metal sulfide, preferably sodium or potassium sulfide, in the form of a hydrate or a hydrous mixture, optionally with a small amount of an alkali metal hydroxide, such as sodium or potassium hydroxide, or a mixture thereof, in the molar ratio (a+b):c of 0.75:1 to 1.25:1; (d) 0.2 to 100 mol %, preferably 0.2 to 2 mol %, based on the number of moles of aromatic dihalogen compound, of the reaction mixture, optionally comprising known catalysts, such as alkali metal carboxylates, alkali metal phosphates, alkali metal phosphonates, alkali metal fluorides, alkali metal alkylsulfonates or N,N-dialkylcarboxylic acid amides.
The present invention relates to a process for producing optionally branched polyarylene sulfides from the reaction mixture, characterized in that 5 mol % of an amino acid is added.

It is known that the addition of aromatic polyhalogen compounds, especially aromatic trihalogen compounds, as branching agents to the reaction mixture increases the melt viscosity of polyarylene sulfides.

Using the process according to the invention, it is possible to achieve high melt viscosities without the use of aromatic polyhalogen compounds.

The reaction time may be as long as 24 hours, but is preferably 2 to 4 hours.
The reaction time is preferably 18 hours. The reaction temperature is 150 to 280°C.

The reaction can be carried out in various ways: the alkali metal sulfide is preferably used in the form of a hydrate and a water-containing mixture or an aqueous solution. The dehydration can be partial, but is preferably complete. The water present in the reaction mixture is removed therefrom by distillation. The removal of water by distillation can be carried out directly or with the aid of an azeotrope-forming agent, but it is preferred to use an aromatic dihalogen compound as the azeotrope-forming agent.
For dehydration, all reactants may be mixed and the mixture subjected to dehydration as a whole.

The reactants are preferably mixed continuously with the amino acid used according to the invention in the presence of a polar solvent, with the removal of water. When this procedure is followed, the reaction can be controlled by the rate of addition, once the reaction has started. This avoids long residence times of water. Compared to the process according to, for example, German Patent Publication No. 3,243,189, in which water is also removed from the reaction,
The process of the present invention makes it possible to obtain relatively light-colored polyarylene sulfides which have relatively high impact strength and which, when melted, evolve relatively little acid gas and thus have the additional advantage of being less corrosive to processing machinery.

If dehydration is complete, the reaction is continued in the absence of pressure or for about 3 minutes.
The reaction can be carried out under pressure up to 50 bar. By using higher pressures up to 50 bar, it is possible to obtain reaction temperatures above the boiling point of the solvent or the mixture of solvent and aromatic dihalogen and polyhalogen compounds.

The reaction mixture can be worked up and the polyarylene sulfide isolated by known methods.

The polyarylene sulfide can be isolated from the reaction solution by known methods, either directly or after the addition of, for example, water and/or dilute acid or an organic solvent in which the polyarylene sulfide is poorly soluble, for example, by filtration or centrifugation. Generally, the separation of the polyarylene sulfide is followed by washing with water. Washing or extraction with other washing solvents, which may be carried out in addition to or after the water wash, is also possible.

The polyarylene sulfide can also be recovered, for example, by distilling off the solvent and washing as described above.

Alkali metal sulfides can be obtained, for example, from _H2S and an alkali metal hydroxide, or from a hydrosulfide and an alkali metal hydroxide.

Depending on the amount of alkali metal hydrosulfide present in the reaction solution as an impurity in the alkali metal sulfide, an appropriate amount of alkali metal hydroxide may be additionally introduced. Instead of alkali metal hydroxide, a compound which separates or generates alkali metal hydroxide under reaction conditions may also be added.

According to the present invention, aromatic meta- and para-dihalogen compounds corresponding to the general formulae (I) and (II) can be used. The ratio of aromatic meta-dihalogen compounds to para-compounds can be up to 30:70.

In order to obtain thermoplastically processable polyarylene sulfides, it is particularly preferred to use aromatic p-dihalogen compounds.

If it is intended to prepare branched polyarylene sulfides, at least 0.005 mole % of aromatic trihalogen or tetrahalogen compound (III) should be used.

Examples of aromatic dihalogen compounds corresponding to general formula (I) which can be used according to the invention are p-dichlorobenzene, p-dibromobenzene, 1-chloro-4-bromobenzene, 1,3-dichlorobenzene, 1,3-dibromobenzene and 1-chloro-3-bromobenzene, which can be used alone or in mixtures with one another. 1,4-Dichlorobenzene and/or 1,4-dibromobenzene are particularly preferred.

Examples of aromatic dihalogen compounds corresponding to general formula (II) which can be used according to the invention are 2,5-dichlorotoluene, 2,5-dichloroxylene, 1-ethyl-2,5-dichlorobenzene, 1-ethyl-2,5-dibromobenzene,
1-ethyl-2-bromo-5-chlorobenzene, 1,2,4,
5-tetramethyl-3,5-dichlorobenzene, 1-cyclohexyl-2,5-dichlorobenzene, 1-phenyl-2,5
-dichlorobenzene, 1-benzyl-2,5-dichlorobenzene, 1-phenyl-2,5-dibromobenzene, 1-
p-tolyl-2,5-dichlorobenzene, 1-p-tolyl-2,5-dibromobenzene, 1-hexyl-2,5-dichlorobenzene, 2,4-dichlorotoluene, 2,4-dichloroxylene, 2,4-dibromocumene, and 1-cyclohexyl-3,5-dichlorobenzene, which can be used either alone or in mixtures with one another.

Examples of aromatic trihalogen and tetrahalogen compounds corresponding to general formula (III) suitable for use in the present invention are 1,2,3-trichlorobenzene, 1,2,4-trichlorobenzene, 1,2,4-tribromobenzene, 1,3,5-trichloro-2,4,5-trimethylbenzene, 1,2,3-trichloronaphthalene, 1,2,4-trichloronaphthalene, 1,2,6-trichloronaphthalene, 2,3,4-trichlorotoluene, 2,3,6
-Trichlorotoluene, 1,2,3,4-tetrachloronaphthalene, 1,2,4,5-tetrachlorobenzene, 2,2',4,4'-
Tetrachlorobiphenyl and 1,3,5-trichlorotriazine.

In general, various polar solvents can be used for the reaction, which ensure adequate solubility of the organic and, optionally, inorganic reactants under the reaction conditions. Preferred solvents are N-alkyl lactams.

N-Alkyl lactams are derived from _C3 to _C11 amino acids, optionally substituted on the carbon chain, which are inert under the reaction conditions.

The N-alkyl lactams used are, for example, N-methyl-caprolactam, N-ethyl-caprolactam,
N-isopropyl-caprolactam, N-isobutyl-
Caprolactam, N-propyl-caprolactam, N-
Butyl-caprolactam, N-cyclohexyl-caprolactam, N-methyl-2-pyrrolidone, N-ethyl-
2-pyrrolidone, N-isopropyl-2-pyrrolidone,
N-isobutyl-2-pyrrolidone, N-propyl-2-
pyrrolidone, N-butyl-2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N-methyl-3-methyl-
2-pyrrolidone, N-cyclohexyl-2-pyrrolidone, N-methyl-3-methyl-2-pyrrolidone, N-methyl-3,4,5-trimethyl-2-pyrrolidone, N-methyl-2-piperidone, N-ethyl-2-piperidone, N
-isopropyl-2-piperidone, N-isobutyl-2
-piperidone, N-methyl-6-methyl-2-piperidone, N-methyl-3-ethyl-2-piperidone.

Mixtures of the above solvents may also be used.

Amino acids suitable for use in accordance with the present invention are preferably linear or cyclic aliphatic _C1 to _C20 amino acids, which may be, for example, _C1 to _C4 alkyl, _C6 to _C14 aryl or combinations thereof, _C1 to _C4 alkylthio-
It may have side chains such as _C1 - _C4 alkyl or heterocyclic _C6 - _C14 groups containing up to 3 heteroatoms such as N, O and S. Amino groups include _NH2 , NRH
or as _NR2 , where R represents an alkyl group, preferably a _C1 - _C4 -alkyl group.
The R groups may be the two termini of an alkylene chain containing a pendant carboxyl group, which together with the NH group form a ring.

The amino groups can be attached in the α-, β-, γ- or ε-position. Diamino acids or aminodicarboxylic acids can also be used.

Examples include the following amino acids: glycine, α-alanine, β-alanine (α- and β-aminopropionic acid), α-aminobutyric acid, γ-aminobutyric acid, α
-aminoisovaleric acid (valine), α-aminoisocaproic acid (leucine), ε-aminocaproic acid, 11-aminoundecanoic acid, N-methylaminoacetic acid (sarcosine),
N-methyl-α-aminopropionic acid, N-methyl-β
-aminopropionic acid, N-methyl-γ-aminobutyric acid,
N-methyl-ε-aminocaproic acid, N-methyl-11-
Aminoundecanoic acid, aminobutanedioic acid (aspartic acid), 2-aminopentanedioic acid (glutamic acid), 2-
Amino-4-methyl-thiobutanoic acid (methionine), phenylalanine, proline.

The amount of the amino acid used in the present invention is 0.2 to 100 mol %, preferably 100 mol %, based on the mole number of the aromatic dihalogen compound.
It is 0.2 to 25 mole %; if it is less than 0.2 mole %, it is ineffective, and if it is more than 100 mole %, the polymerization reaction is hindered.

The reaction can be carried out in the presence of conventional catalysts, such as alkali metal carboxylates (German Patent Publication No. 2,453,749), lithium halides or alkali metal carboxylates (German Patent Publication No. 2,623,362), lithium chloride or lithium carboxylate (German Patent Publication No. 2,623,363),
Alkali metal carbonates in combination with alkali metal carboxylates (U.S. Pat. No. 4,038,259), lithium acetate (German Patent Publication No. 2,623,333), trialkali metal phosphates (German Patent Publication No. 2,930,710); trialkali metal phosphonates (German Patent Publication No. 2,930,797
No.), alkali metal fluorides (German Patent Publication No. 3,019,
732), alkali metal sulfonates (U.S. Pat. No. 4,033,
No. 8,269), and lithium carbonate and lithium borate (U.S. Pat. No. 4,039,518).

The polyarylene sulfide according to the present invention can be mixed with other polymers such as pigments and fillers, for example, graphite, metal powder, glass powder, quartz powder, glass fiber or carbonate fiber, and additives commonly used for polyarylene sulfides, such as stabilizers or mold release agents, can also be added thereto.

Generally, the melt flow index of polyarylene sulfides is measured in accordance with ASTM 1238-70 at 316°C using a 5 kg weight and is expressed in units of g/10 min.

However, at high melt flow indices, this measurement becomes difficult due to the high flow rate of the polymer melt.

Therefore, the melting point ηm of a polymer is measured at 306° C. as a function of the shear stress τ (in Pa) using an Instron rotational viscometer.

This method allows the measurement of melt viscosity over a very wide range, from ^10-1 to ^10-7 Pa.s. In an Instron rheometer, the polymer is melted between a fixed plate and a rotating cone, and the torque of the cone is measured. From this torque, angular velocity, and instrument data, the relationship between melt viscosity and shear stress can be calculated. An Instron Model 3250 rheometer with a 2 cm diameter cone and plate was used.

The results are given as melt viscosity measured at a shear stress of τ=10 ² Pa.

It is also possible to obtain information about molecular weight and molecular weight distribution by analyzing polyarylene sulfides by chromatographic methods, typical examples of which are high pressure liquid chromatography (HPLC) and gel permeation chromatography (GPC).

The stationary phase may be a commercially available support material, such as Li-Crop.
Rep (Chroprep), Rover (Lobar), Li-chlor
Sorb (Chrosorb), Li Crossfor (Chrosphe
r), Perisorb (Perisorb), Hibar (Hibe
r), Fractogel (Fractogel), Fractosil
(Fractosil), Ultrastyragel (Ultorastyra
gel), Microstyragel, Zobatsu
Kus (Zorbax), Bondagel (Bondagel) and Shio
Shodex can be used.

As the solvent and eluent, conventional solvents and diluents can be used. These solvents and diluents must be sufficient to dissolve the polymer. Examples include 1-chloronaphthalene, diphenyl, N-methyl-pyrrolidone,
N-cyclohexyl-pyrrolidone, N-methyl-piperidine, N-methylcaprolactam, N-methyl-laurinlactam, sulfolane, N,N'-dimethyl-imidazolidone, N,N'-dimethylpiperazinone, hexamethyl-phosphoric triamide (NMP), 1-methyl-1-oxaphospholane and mixtures thereof.

It is possible to calibrate the analytical method by means of absolute or relative standards. Reference materials for relative calibration include common polymers such as polystyrene, polyethylene, polyethylene-terephthalate, polybutylene-terephthalate, polyesters such as aromatic polyesters, polycarbonates such as PA6, PA6
6. Polyamides such as PA11, polysulfones and polyethersulfones can be used.

Chromatography for analytical determination of molecular weight or molecular weight distribution can be carried out at various pressures from about 1 to 10 bar.

Chromatography can be carried out over a wide temperature range from about 20 to 250°C.

Furthermore, for purposes of improvement, it is also possible to add substances such as alkali halides, alkaline earth halides, phosphonium or ammonium compounds to the sample to be analyzed.

The weight average molecular weight Mw can be determined by analyzing the analytical results thus obtained.

The weight average molecular weight Mw is 25,000 to 500,000, preferably 25,000
It is preferably 0 to 380,000, more preferably 25,000 to 300,000, and most preferably 25,000 to 150,000.

In the case of a linearly polymerized polyarylene sulfide, the melt viscosity ηm and the weight average relative molecular weight Mw are characterized by the relationship _logηm = 3.48 logMw(rel) - 14.25 ± 0.1, and the melt viscosity ηm is 20 to 500,000 Pa.s and the weight average relative molecular weight Mw is 25,000 to 500,000.
(rel).

In the case of a linearly polymerized polyarylene sulfide, it is preferable that the relationship between ηm and Mw is as shown in the following formula.

_logηm = 3.48· _logMw (rel)−14.25±0.05 The polyarylene sulfide according to the present invention, preferably p
- polyarylene sulfide, immediately after isolation from the reaction mixture, generally has a viscosity of 0.3 x 10 ³ to 5 x 10 ⁶ Pa.s, preferably
The resulting polymers have a melt viscosity of 1.5 x ¹⁰³ to ¹⁰⁴ Pa.s and good color properties. They can be directly processed into films, molded parts, or fibers by extrusion, extrusion blowing, injection molding, or other conventional processing methods. The resulting products can be used for conventional purposes, such as automobile parts, accessories, electrical parts such as switches or electronic panels, pump housings and pump impellers, caustic bath pans, sealing rings, parts for office machines and communication devices, household appliances, valves, and ball bearing parts, and other parts and devices requiring chemical and weather resistance.

Example 1 This example describes, for comparative purposes, the preparation of polyphenylene sulfide in accordance with US Pat. No. 3,354,129.

129 g of sodium sulfide trihydrate (1 mole of _Na2S
100 g of N-methyl-2-pyrrolidone (corresponding to 100 g of N-methyl-2-pyrrolidone) was placed in an autoclave equipped with a stirrer. The mixture was flushed with nitrogen and gradually heated to 202°C. During this process, 19 ml of water was distilled. The reaction mixture was then heated to about 160°C.
Cool to 0°C and dissolve in 50g of N-methyl-2-pyrrolidone
147 g of p-dichlorobenzene (=1 mole) was added. The reaction mixture was heated to 245°C under an initial pressure of 2.5 bar for 30 minutes, during which time the pressure rose to 10 bar and the temperature was maintained at this level for 3 hours. After cooling to room temperature, the grey solid was isolated and then carefully washed with water to remove inorganic impurities.

After drying under vacuum at 80°C, 100.3 g (93%) of poly-p-phenylene sulfide was obtained having the following characteristics: melt viscosity = 4.5 Pa.s (at τ = 10 ² Pa); thermoplastic processing was not possible without curing.

Example 2 1110 g N-methyl-caprolactam, 323.5 g sodium sulfide hydrate 2.4 g of 50% sodium hydroxide, 341.1 g of 1,4-dichlorobenzene 28.53 g of sodium acetate and 5.07 g of ε-aminocaproic acid (0.035 moles) are introduced under nitrogen into a 2-liter three-neck flask equipped with a thermometer, stirrer, and distillate separator. The reaction mixture is gradually heated to boiling. Water is separated from the distillate azeotrope of water and p-dichlorobenzene, and the p-dichlorobenzene is returned to the reactor. After 2 hours, no water is detected in either the distillate or the residue. After a further 9 hours of heating under reflux, the product is isolated as white fibers by conventional methods: precipitation in water, acidification, washing with water to remove electrolytes, and drying. The product is characterized by measuring its melt viscosity: _ηm = 3.6 × ^10² Pa.s (for τ = ^10² Pa).

Example 3: The procedure was the same as in Example 2, except that 2.1 g of 1,2,4-trichlorobenzene (0.5 mol % based on the moles of dihalogenobenzene) was added as a branching agent to the reaction mixture. The reaction and post-treatment were the same as in Example 2. Melt viscosity ηm = 1.8
× 10 ³ Pa.s (for τ = 10 ² Pa).

Example 4: 4.09 g (0.035 mol) of δ-aminocaproic acid was used instead of ε-aminocaproic acid.
The procedure is the same as in Example 2, except that α-amino-butyric acid is used.

Melt viscosity η _m =3.2×10 ² Pa.s (for τ=10 ² Pa).

Example 5 In the same apparatus as in Example 2, 1110 g of N-methyl-caprolactam, 323.5 g of sodium sulfide hydrate 28.0 g of 50% sodium hydroxide, 34.1 g of 1,4-dichlorobenzene 2.52 g of 1,2,4-trichlorobenzene (0.5 mol % relative to the moles of p-dihalogenobenzene), 30.2 g of N,N-dimethylacetamide (15 mol %) and 5.07 g (0.035 mol) of ε-aminocaproic acid are introduced. The reaction mixture is slowly heated to boiling. Water is separated from the azeotropic mixture of water and p-dichlorobenzene that distills off, and the p-dichlorobenzene is returned to the reaction. After 2 hours, no water can be detected in either the distillate or the residue. After a further 9 hours of heating under reflux, the product is worked up as in Example 2.

η _m =2.3×10 ³ Pa.s (for τ = 10 ² Pa).

Example 6: Dehydration was carried out in the same manner as in Example 2, except that 33.64 g of ε-aminocaproic acid was used and N-methyl-caprolactam and p-dichlorobenzene, and also sodium sulfide hydrate, ε-caprolactam and sodium acetate were mixed simultaneously. The subsequent reaction and post-treatment were the same as in Example 2.

η _m =3.6×10 ² Pa.s (for τ = 10 ² Pa).

Example 7 The procedure was the same as in Example 6, except that sodium acetate was not used.

η _m = 1.3×10 ² Pa.s (for τ = 10 ² Pa).

Example 8: In place of ε-aminocaproic acid in Example 6, glycine
The same procedure as in Example 6 was repeated except that 7.4 g was used.

ηm=2.0×10 ² Pa·s (for τ=10 ² Pa) The weight average relative molecular weight (Mw) and melt viscosity (ηm) in Examples 1 to 8 are shown in the table below.

Unlike Example 1, the p-polyphenylene sulfides of Examples 2 to 8 are all directly thermoplastically processable.

p-Polyphenylene sulfide prepared according to Example 2 of the German Patent Publication (removal of water from the reaction, no addition of amino acid) is darker in color both before and after melting and releases acidic, corrosive gaseous components to a greater extent upon melting than p-polyphenylene sulfide prepared according to the present invention.

The melting was carried out at 320°C, and the acid gas was sent to a gas washing bottle containing 1N sodium hydroxide solution together with nitrogen as a carrier gas, and the sodium hydroxide consumed by neutralization was determined by titration.

──────────────────────────────────────────────────── Continued from the front page (72) Inventor: Wolfgang Allebert 4150 Krefeld, Federal Republic of Germany 32nd Bodelschuhingstrasse

Claims (9)

[Claims] [Method for producing polyarylene sulfides] Claim 1: (a) 50 to 100 mol % of the following general formula (I):
Aromatic dihalogen compounds corresponding to and 0 to 50 mol % of an aromatic dihalogen compound corresponding to the following general formula (II): In these formulas, X represents a halogen atom in the meta- or para-position relative to each other, and R ¹ may be the same or different and is hydrogen, alkyl, cycloalkyl, aryl, alkylaryl,
arylalkyl, and in addition, two R ^groups in the ortho-position relative to each other may be joined to form an aromatic or heterocyclic ring, and one of the ^R groups is always different from hydrogen; and (b) 0 to 5, based on the sum of components (a) and (b).
% of aromatic trihalogen or tetrahalogen compounds ArXn (III) corresponding to the following general formula (III) in which Ar represents an aromatic or heterocyclic group; X represents a halogen; and n represents the number 3 or 4; and (c) a molar ratio of alkali metal sulfides (a+b):C of 0.85:1 to 1.15:1; (d) in a polar solvent in a molar ratio of (a):(c) of 0.75:1 to 1.25:1 and a molar ratio of (c):(d) of 1:2 to 1:1.
5 and (e) based on the number of moles of aromatic dihalogen compound, 0.
A method for producing high molecular weight polyarylene sulfides, which comprises carrying out a reaction in the presence of 2 to 100 mol % of an amino acid. 2. The method according to claim 1, wherein the amino acid is added in an amount of 0.2 to 25 mol % based on the number of moles of the aromatic dihalogen compound. 3. The method according to claim 1, wherein an aliphatic amino acid is used. 4. The method according to claim 1, wherein glycine, α- and β-alanine, γ-aminobutyric acid, ε-aminocaproic acid, 11-aminoundecanoic acid and their N-methylated derivatives are used. 5. The process of claim 1, wherein the water-containing reactants are completely dehydrated and the reaction is carried out in the absence of pressure or under low pressure. 6. The method of claim 1, wherein the reactants and the polar solvent are reacted individually or in the form of a mixture or solution at a temperature of 200°C.
2. The method of claim 1, wherein the mixing and reaction are carried out accompanied by dehydration. 7. The method according to claim 1, wherein N-methyl-ε-caprolactam is used as the polar solvent.
The method described in section. 8. Aromatic dihalogen compound (I) containing 1,4
2. A process according to claim 1, characterized in that dichlorobenzene is used. 9. As an aromatic polyhalogen compound (III),
2. The process according to claim 1, wherein 1,2,4-trichlorobenzene is used.