阅读说明：本技术 阳离子亚砜中间体、聚芳硫醚单体及聚芳硫醚的制备方法 (Cationic sulfoxide intermediate, polyarylene sulfide monomer and preparation method of polyarylene sulfide ) 是由 何柏贤 林志祥 陈孟歆 范正欣 高信敬 张义和 于 2017-01-11 设计创作，主要内容包括：一种阳离子亚砜中间体的制备方法,其中该阳离子亚砜中间体具有式(I)所示结构：<Image he="380" wi="607" file="DDA0002587905680000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>其中Ar<Sub>1</Sub>以及Ar<Sub>2</Sub>是取代或未取代芳香基,且Ar<Sub>1</Sub>以及Ar<Sub>2</Sub>相同或不同。该方法包含：将过氧化氢与(i)硫酸,以及(ii)具有式(IV)所示结构的阳离子硫醚中间体进行反应,以获得该阳离子亚砜中间体,<Image he="236" wi="700" file="DDA0002587905680000012.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>其中Ar<Sub>1</Sub>以及Ar<Sub>2</Sub>的定义如上,而<Image he="112" wi="130" file="DDA0002587905680000013.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>是一阴离子。(A kind ofA method for preparing a cationic sulfoxide intermediate, wherein the cationic sulfoxide intermediate has the structure shown in formula (I): wherein Ar is 1 And Ar 2 Is a substituted or unsubstituted aromatic radical, and Ar 1 And Ar 2 The same or different. The method comprises the following steps: reacting hydrogen peroxide with (i) sulfuric acid, and (ii) a cationic thioether intermediate having a structure represented by formula (IV), to obtain the cationic sulfoxide intermediate, wherein Ar is 1 And Ar 2 Is as defined above, and is an anion.)

1. A method for preparing a cationic sulfoxide intermediate, wherein the cationic sulfoxide intermediate has a structure represented by formula (I):

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic radical, and Ar₁And Ar₂The same or different, and the same or different,

the preparation method comprises the following steps:

reacting hydrogen peroxide with (i) sulfuric acid, and (ii) a cationic thioether intermediate having a structure represented by formula (IV), to obtain the cationic sulfoxide intermediate,

wherein Ar is₁And Ar₂Is as defined above, andis an anion.

2. The method of preparing a cationic sulfoxide intermediate according to claim 1, wherein the method comprises:

reacting a compound with a structure shown in a formula (V) with a compound with a structure shown in a formula (VI) in an acidic environment,

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic radical, and Ar₁And Ar₂The same or different.

3. The method of preparing a cationic sulfoxide intermediate of claim 1, wherein Ar₁And Ar₂Is phenyl.

4. The method for preparing a cationic sulfoxide intermediate according to claim 1, wherein the molar ratio of the hydrogen peroxide to the sulfuric acid is 2: 1 to 4: 1.

5. The method for producing a cationic sulfoxide intermediate according to claim 2, wherein the compound having a structure represented by formula (V) is thioanisole or 1-methylsulfanyl-4-phenylbenzene.

6. The method for producing a cationic sulfoxide intermediate according to claim 2, wherein the compound having a structure represented by formula (VI) is methylphenyl sulfoxide.

7. The method of claim 2, wherein the acidic environment is formed by the addition of methanesulfonic acid, benzenesulfonic acid, p-toluenesulfonic acid, sulfuric acid, or trifluoromethanesulfonic acid.

8. A method for preparing a polyarylene sulfide monomer, wherein the polyarylene sulfide monomer has a structure represented by formula (VII):

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic radical, and Ar₁And Ar₂The same or different, and the same or different,

the preparation method comprises the following steps:

a method for preparing the cationic sulfoxide intermediate of claim 1; and

and demethylating the cationic sulfoxide intermediate to obtain the polyarylene sulfide monomer.

9. The method for producing polyarylene sulfide monomer according to claim 8, wherein the method does not use halogen.

10. A process for producing a polyarylene sulfide, wherein the polyarylene sulfide has a structure represented by the formula (VIII),

the preparation method comprises the following steps: the polymerization is carried out as described in claim 8The polyarylene sulfide monomer obtained by the process, wherein Ar₁And Ar₂Is a substituted or unsubstituted aromatic radical, and Ar₁And Ar₂The same or different, and n is an integer of 1 to 1000.

Technical Field

The invention relates to a cationic sulfoxide intermediate, a polyarylene sulfide monomer and a preparation method of polyarylene sulfide.

Background

Polyarylene sulfides (PAS), for example: polyphenylene Sulfide (PPS) has good heat resistance, chemical resistance, and mechanical strength, and has a lower density than metal, and thus can be widely used in light weight products in the electronics and automobile industries. In addition, the polyarylene sulfide has excellent application in the processes of spinning fiber filter materials, connectors, coating materials and electronic components. In the conventional polyarylene sulfide preparation technology, p-dichlorobenzene (p-dichlorobenzzene) is used as a monomer to react with sodium sulfide (sodium sulfide). Since the above-mentioned process is a halogen-containing process, a large amount of alkali metal halide (by-product) is present in the resulting polyarylene sulfide in the preparation of the polyarylene sulfide, and therefore further purification of the polyarylene sulfide is required. However, purification of polyarylene sulfide to remove the halide not only increases the cost of producing the polyarylene sulfide, but also deteriorates the properties of the polyarylene sulfide because the halide is not easily removed from the polyarylene sulfide completely.

JP 07-304872a discloses that thioanisole (thioanisole) can be reacted with methyl phenyl sulfoxide (methyl phenyl sulfoxide) in an acidic environment (acidity control) and an electrophilic substitution mechanism (electrophilic substitution mechanism) is performed to prepare a monomeric cationic intermediate (containing sulfonium group) for synthesizing polyphenylene sulfide (PPS). The cationic intermediate can be demethylated to yield a neutral disulfide (dithioether) compound. The reaction formula (I) of the above reaction is as follows:

then, after the reaction of formula (I), bromine (Br) is used₂) And potassium bicarbonate (KHCO)₃) The neutral disulfide (dithioether) compound is oxidized to obtain a monomer (having a sulfoxide group) that can be used for synthesizing polyphenylene sulfide (PPS). Then, the monomer is reacted in the presence of an acid to obtain a polysulfonium salt intermediate; the polysulfonium salt intermediate is then demethylated to yield a neutral polyarylene sulfide. The reaction formula (II) of the above reaction is as follows:

however, with halogens (e.g. Br)₂) To comeThe oxidation reaction proceeds to produce many halogen-containing by-products which cannot be recovered, and besides causing environmental pollution, it also results in the need to purify the resulting polyarylene sulfide by an additional step, resulting in an increase in cost, which is disadvantageous for the production of polyarylene sulfide. Therefore, there is a need for a new method for preparing polyarylene sulfide monomers to avoid halogen (e.g. Br)₂) The use of (1).

Disclosure of Invention

According to an embodiment of the present invention, there is provided a method of preparing polyarylene sulfide monomer without using halogen (halogen). In addition, according to the embodiments of the present invention, the present invention utilizes a selective oxidation process to prepare polyarylene sulfide monomers, so as to avoid the formation of sulfone (sulfones) and sulfoxide (sulfoxides) type byproducts due to different oxidation states during the preparation process.

According to an embodiment of the present invention, the present invention provides a method for preparing a cationic sulfoxide intermediate (cationic sulfoxide intermediate), wherein the cationic sulfoxide intermediate has a structure represented by formula (I):

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic radical, and Ar₁And Ar₂The same or different. The preparation method of the cationic sulfoxide intermediate comprises the following steps: reacting hydrogen peroxide with (i) sulfuric acid, and (ii) a cationic thioether intermediate having a structure represented by formula (IV) to obtain the cationic sulfoxide intermediate,

wherein Ar is₁And Ar₂Is as defined above, and

is an anion.

According to another embodiment of the present invention, there is provided a method for preparing polyarylene sulfide monomer, wherein the polyarylene sulfide monomer has a structure represented by formula (VII):

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic radical and Ar₁And Ar₂The same or different. The preparation method of the polyarylene sulfide monomer (polyarylene sulfoxide monomer) comprises the preparation method of the cationic sulfoxide intermediate (cationic sulfoxide intermediate); and demethylating the cationic sulfoxide intermediate (cationic sulfoxide intermediate) to obtain the polyarylene sulfide monomer with the structure shown in the formula (VII).

According to still another embodiment of the present invention, there is provided a method for preparing a polyarylene sulfide, wherein the polyarylene sulfide has a structure represented by formula (VIII):

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic radical, and Ar₁And Ar₂The same or different, and n is an integer of 1 to 1000. The method of preparing the polyarylene sulfide comprises polymerizing the polyarylene sulfide monomer described above.

Drawings

FIG. 1 is a Nuclear Magnetic Resonance (NMR) spectrum of a methylphenyl [4- (methylthio) phenyl ] sulfonium perchlorate (4- (methylthio) phenyl ] sulfonium perchlorate) prepared in an example of the present invention.

FIG. 2 is a Nuclear Magnetic Resonance (NMR) spectrum of methyl4- (phenylthio) phenylsulfoxide (methyl4- (phenylthio) phenylsulfoxide) prepared in the example of the present invention.

FIG. 3 is a Nuclear Magnetic Resonance (NMR) spectrum of a methylphenyl [4- (methylthio) biphenyl ] sulfonium perchlorate (methyl phenyl [4- (methylthio) biphenyl ] sulfonium perchlorate) prepared in an example of the present invention.

FIG. 4 is a spectrum of a methylphenyl [4- (methylthio) biphenyl ] sulfonium perchlorate (methyl phenyl [4- (methylthio) biphenyl ] sulfonium perchlorate) prepared in the example of the present invention, measured by liquid chromatography-tandem mass spectrometry (LC-MS).

FIG. 5 is a Nuclear Magnetic Resonance (NMR) spectrum of methyl4- (phenylthio) biphenyl sulfoxide (methyl4- (phenylthio) biphenyl sulfoxide) prepared in the example of the present invention.

FIG. 6 is a graph of methyl4- (phenylthio) biphenyl sulfoxide (methyl4- (phenylthio) biphenyl sulfoxide) measured by liquid chromatography-tandem mass spectrometry (LC-MS) according to the present invention.

FIG. 7 is a Differential Scanning Calorimetry (DSC) profile of polyphenylene sulfide obtained in examples of the present invention.

FIG. 8 is a Nuclear Magnetic Resonance (NMR) spectrum of methyl4- (phenylthio) phenylsulfoxide (methyl4- (phenylthio) phenylsulfoxide) prepared in the example of the present invention.

Detailed Description

In order that the objects, technical solutions and advantages of the present invention will become more apparent, the present invention will be further described in detail with reference to the accompanying drawings in conjunction with the following specific embodiments.

According to an embodiment of the present invention, the present invention provides a method for preparing a cationic sulfoxide intermediate (cationic sulfoxide intermediate), wherein the cationic sulfoxide intermediate has a structure represented by formula (I):

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic group. Ar (Ar)₁And Ar₂Identical or different, e.g. phenylenee group), biphenylene group (biphenylene group), naphthylene group (naphthylene group), thienylene group (thienylene group), tolylene group (tolylene group), tolylene group (xylenylene group), indolylene group (indolylene group), tetrahydronaphthylene group (tetrahydronaphthylene group), phenanthrylene group (phenylnaphthylene group), biphenylene group (biphenylylene group), indenenylene group (indolynylene group), anthracenylene group (anthracenylene group), or fluorenylene group (fluoroenylene group). The aromatic group of the present invention may be a single ring, two fused rings (two fused rings) or three fused rings (three fused rings). For example, the aryl group may be phenyl or biphenyl.

The preparation method of the cationic sulfoxide intermediate comprises the following steps: reacting hydrogen peroxide with (i) a compound having a structure represented by formula (II) or R' SO₃H structural sulfonic acid or sulfuric acid (wherein R' is-CH)₃、-CF₃Phenyl (-C)₆H₅) Or tolyl (-C)₆H₄CH₃) or-OH), and (ii) a cationic thioether intermediate (cationic sulfoxide intermediate) having a structure represented by formula (IV) to obtain the cationic sulfoxide intermediate (cationic sulfoxide intermediate),

wherein R is substituted or unsubstituted C_1-6An alkyl group; and wherein Ar₁And Ar₂Is as defined above, and Y is an anion. In accordance with an embodiment of the present invention,can be, for example, HSO₄ ^-、CH₃SO₃ ^-、PhSO₃ ^-(C₆H₅SO₃ ^-)、p-tolSO₃ ^-(CH₃C₆H₄SO₃ ^-) Or CF₃SO_3-。

According to an embodiment of the present invention, the method for preparing the cationic sulfoxide intermediate may comprise reacting hydrogen peroxide with a compound having a structure represented by formula (II) to obtain a compound having a structure represented by formula (III-a):

wherein R is substituted or unsubstituted C_1-6An alkyl group; and reacting the compound having the structure represented by formula (III-A) with a cationic thioether intermediate having the structure represented by formula (IV).

According to an embodiment of the present invention, the method for preparing the cationic sulfoxide intermediate may comprise reacting hydrogen peroxide with sulfonic acid (sulfonic acid) or sulfuric acid (structure R' SO)₃H) Reacting to obtain a compound with a structure shown as a formula (III-B)

Wherein R' is hydrogen, -CH₃、-CF₃Phenyl (-C)₆H₅) Tolyl group (-C)₆H₄CH₃) or-OH; and reacting the compound having the structure represented by formula (III-B) with a cationic thioether intermediate having the structure represented by formula (IV).

According to an embodiment of the present invention, the molar ratio of the hydrogen peroxide to the compound having the structure represented by formula (II) may be 2: 1 to 4: 1. According to an embodiment of the invention, the hydrogen peroxide is reacted with the sulfonic acid (sulfonic acid) or sulfuric acid (R' SO)₃H) Can be from 2: 1 to 4: 1.

According to embodiments of the invention, R may be methyl. Further, R may be a straight chain C_1-6Alkyl or R may be cycloalkyl.

According to an embodiment of the present invention, the cationic thioether intermediate having a structure according to formula (IV) may be mixed with the compound having a structure according to formula (II) before adding hydrogen peroxide.

According to embodiments of the invention, the above reaction may be continued at 10 to 40 ℃ (e.g., 20 to 25 ℃) for 60 to 120 minutes (e.g., 80 to 90 minutes).

The cationic thioether intermediate can be prepared by reacting a compound having a structure represented by formula (V) with a compound having a structure represented by formula (VI) in an acidic environment (acidic condition),

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic group. Ar (Ar)₁And Ar₂May be the same or different, such as phenylene group (phenylene group), biphenylene group (biphenylene group), naphthylene group (naphthylene group), thienylene group (thienylene group), tolylene group (tolylene group), tolylene group (xylylene group), indolylene group (indolylene group), tetrahydronaphthylene group (tetrahydronaphthylene group), phenanthrylene group (phenanthrylene group), biphenylene group (biphenylene group), indolylene group (indolylene group), anthracenylene group (anthrylene group), or fluorenylene group (fluorrylene group). According to an embodiment of the present invention, Ar₁And Ar₂May be phenylene group or biphenylene group, the compound having the structure of formula (V) may be thioanisole (thioanisole) or 1-methylsulfanyl-4-phenylbenzene (1-methylsulfanyl-4-phenylbenzen), and the compound having the structure of formula (VI) may be methyl phenyl sulfoxide (methyl phenyl sulfoxide). According to an embodiment of the present invention, the acidic environment can be created by adding sulfonic acid or sulfuric acid (structure R' SO)₃H, wherein R' is-CH₃、-CF₃Phenyl (-C)₆H₅) Tolyl group (-C)₆H₄CH₃) or-OH). In other words, the acidic environment (acidic condition) can be formed by adding methanesulfonic acid (methansulfonic acid), benzenesulfonic acid (benzylsulfonic acid), p-toluenesulfonic acid (p-toluenesulfonic acid), sulfuric acid (sulfuric acid), or trifluoromethanesulfonic acid (trifluoromethanesulfonic acid). According to the embodiment of the inventionThe same number of moles of thioanisole (thioanisole) and methyl phenyl sulfoxide (methyl phenyl sulfoxide) can be mixed and reacted under an acidic condition at a temperature of 0 to 25 ℃ and a pressure of 0.5 to 1.5atm (e.g., 1 atm). According to embodiments of the present invention, the compound having the structure shown in formula (V) and the compound having the structure shown in formula (VI) may be mixed at 0 deg.C and gradually warmed to room temperature (e.g., 18 to 25 deg.C) after the addition of the acid. According to an embodiment of the present invention, the above reaction may last for 10 to 30 hours (e.g., 20 hours).

The following reaction scheme is used to illustrate the reaction mechanism for reacting a compound having the structure shown in formula (II) with hydrogen peroxide and a cationic thioether intermediate:

the following equations are provided to illustrate the reaction of sulfonic acid (sulfonic acid) or sulfuric acid (R' SO)₃H) Reaction mechanism with hydrogen peroxide and cationic thioether intermediate:

according to an embodiment of the present invention, there is provided a method for preparing a polyarylene sulfide monomer having a structure represented by formula (VII)

Wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic group. Ar (Ar)₁And Ar₂The same or different, for example, phenylene group (phenylene group), biphenylene group (biphenylene group), naphthylene group (naphthylene group), thienylene group (thienylene group), tolylene group (tolylene group), tolylene group (xylylene group), indolylene group (indolylene group), tetrahydronaphthylene group (tetrahydronaphthylene group), phenanthrylene group (phenylnaphthylene group), biphenylene group (biphenylylene group), indenetyrylene group (biphenylene group), indenethynylene group (biphenylene group)An arylene group, anthracenylene group or fluorenylene group. The aromatic group of the present invention may be a single ring, two fused rings (two fused rings) or three fused rings (three fused rings). For example, the aryl group may be phenyl or biphenyl. The polyarylene sulfide monomer can be methyl4- (phenylthio) phenyl sulfoxide (methyl4- (phenylthio) phenyl sulfoxide). Halogen (halogen) is not used in the process for preparing the polyarylene sulfide monomer.

According to an embodiment of the present invention, the first step of the method for preparing polyarylene sulfide monomer is to prepare the above-mentioned cationic sulfoxide intermediate.

After the above step, the method for preparing the polyarylene sulfide monomer may comprise demethylating the cationic sulfoxide intermediate to obtain the polyarylene sulfide monomer having the structure represented by formula (VII).

A high efficiency nucleophile (nucleophile) may be used to demethylate a cationic thioether intermediate having a structure according to formula (IV). The nucleophile may be, for example, an amine, amide, pyridine, or halide, and the temperature of the demethylation reaction may be from about 20 to about 150 deg.C and the reaction pressure may be from about 0.5 to about 1.5atm (e.g., 1 atm). According to an embodiment of the present invention, the time for the demethylation reaction may last from 20 minutes to 6 hours.

The reaction formula of the preparation method of the polyarylene sulfide monomer is as follows:

according to an embodiment of the present invention, there is provided a method for preparing polyarylene sulfide, wherein the polyarylene sulfide has a structure represented by formula (VIII):

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic group. Ar (Ar)₁And Ar₂The same or different, e.g. phenylene group, biphenylene group, naphthylene groupphenylene group), thienylene group (thienylene group), tolylene group (tolylene group), tolylene group (xylenylene group), indolylene group (indolylene group), tetranaphthylene group (tetrahydronaphthylene group), phenanthrylene group (phenanthrenylene group), biphenylenylene group (biphenylene group), indenenylene group (indolyenylene group), anthracenylene group (anthracenylene group) or fluorenylene group (fluoroenylene group). The aromatic group of the present invention may be a single ring, two fused rings (two fused rings) or three fused rings (three fused rings). For example, the aryl group can be phenyl. The polyarylene sulfide may be polyphenylene sulfide.

n is an integer of 1 to 1000 or an integer of 2 to 1000.

The polyarylene sulfide is obtained by polymerizing the polyarylene sulfide monomer, and the polyarylene sulfide monomer is prepared according to the preparation method of the polyarylene sulfide monomer.

According to the embodiment of the present invention, the same number of moles of thioanisole (thioanisole) and methyl phenyl sulfoxide (methyl phenyl sulfoxide) can be mixed and reacted in an acidic environment (acidic condition), the reaction temperature can be between 0 to 25 ℃, and the reaction pressure can be 0.5 to 1.5atm (e.g. 1 atm). According to an embodiment of the present invention, the acidic condition may be created by adding sulfonic acid or sulfuric acid (structure R' SO)₃H, wherein R' is-CH₃、-CF₃Phenyl (-C)₆H₅) Tolyl group (-C)₆H₄CH₃) or-OH). In other words, the acidic environment (acidic condition) can be formed by the addition of methanesulfonic acid (methansulfonic acid), benzenesulfonic acid (benzylsulfonic acid), p-toluenesulfonic acid (p-toluenesulfonic acid), sulfuric acid (sulfuric acid), or trifluoromethanesulfonic acid (trifluoromethanesulfonic acid).

After the above step, the cationic sulfoxide intermediate can be demethylated to yield a polyarylene sulfide monomer having the structure shown in formula (VII). A high efficiency nucleophile (nucleophile) may be used to demethylate a cationic thioether intermediate having a structure according to formula (IV). The nucleophile may be, for example, an amine, amide, pyridine, or halide, and the temperature of the demethylation reaction may be from about 20 to about 150 deg.C and the reaction pressure may be from about 0.5 to about 1.5atm (e.g., 1 atm). According to an embodiment of the present invention, the time for the demethylation reaction may last from 20 minutes to 6 hours.

According to an embodiment of the present invention, the polyarylene sulfide monomer may be reacted with an acid to obtain a polysulfonium salt intermediate having a structure represented by formula (IX),

wherein Ar is₁And Ar₂Is a substituted or unsubstituted aromatic group. Ar (Ar)₁And Ar₂The same or different, for example, a phenylene group (phenylene group), a biphenylene group (biphenylene group), a naphthylene group (naphthylene group), a thienylene group (thienylene group), a tolylene group (tolylene group), a tolylene group (xylenylene group), an indolylene group (indolylene group), a tetrahydronaphthylene group (tetrahydronaphthylene group), a phenanthrylene group (phenylnaphthylene group), a biphenylene group (biphenylylene group), an indolylene group (biphenylylene group), an anthracenylene group (indolylene group), or a fluorenylene group (fluoroenylene group). The aromatic group of the present invention may be a single ring, two fused rings (two fused rings) or three fused rings (three fused rings). For example, the aryl group can be phenyl.

n is an integer of 1 to 1000 or an integer of 2 to 1000.

Is an anion, e.g. HSO₄ ^-、CH₃SO₃ ^-、PhSO₃ ^-(C₆H₅SO₃ ^-)、p-tolSO₃ ^-(CH₃C₆H₄SO₃ ^-) Or CF₃SO_3-。

The acid used in the above reaction may, for example, have R' SO₃Sulfonic or sulfuric acid of the structure H, wherein R' is-CH₃、-CF₃Phenyl (-C)₆H₅) Tolyl group (-C)₆H₄CH₃) or-OH.

In other words, the acid may be formed of methanesulfonic acid (methanesulfonic acid), benzenesulfonic acid (benzzenesulfonic acid), p-toluenesulfonic acid (p-toluenesufonic acid), sulfuric acid (sulfuric acid) or trifluoromethanesulfonic acid (trifluoromethanesulfonic acid).

According to an embodiment of the present invention, the polyarylene sulfide monomer and the acid may be continuously reacted at 0 ℃ for about 30 minutes to 1 hour. Then, the temperature of the reaction may be raised to room temperature (about 18 to 25 ℃) and the reaction may be continued for 10 to 30 hours (e.g., about 20 hours).

After the above step, the intermediate of the polysulfonium salt having the structure represented by formula (IX) may be demethylated to obtain a polyarylene sulfide having the structure represented by formula (VIII). The polysulfonium salt intermediate can be demethylated using a nucleophile. The nucleophilic agent may be aqueous hydrochloric acid (HCl), aqueous hydrobromic acid (HBr), aqueous hydroiodic acid (HI), an amine, an amide, or pyridine. Here, the acid used to perform demethylation may have an acidity that is stronger than the acidity of the acid used to prepare the polysulfonium salt intermediate.

The polysulphonium salt intermediate (polysulphonium intermediate) may also be demethylated in an organic solvent. The organic solvent may be at least one selected from the group consisting of water, ketone solvents, nitrile solvents, sulfone solvents and amide solvents. In one embodiment of the present invention, the organic solvent may be a solvent mixed with water. In another embodiment of the present invention, the organic solvent may be a solvent mixed with water and acetone.

A high efficiency nucleophile (nucleophile) may be used to demethylate a cationic thioether intermediate having a structure according to formula (IV). The nucleophile may be, for example, an amine, amide, pyridine, or halide, and the temperature of the demethylation reaction may be from about 20 to about 150 deg.C and the reaction pressure may be from about 0.5 to about 1.5atm (e.g., 1 atm). According to the embodiment of the invention, the time of the demethylation reaction can last for 4 to 72 hours. According to an embodiment of the present invention, the demethylation reaction time can last from 20 to 24 hours, and the reaction temperature is from about room temperature to about 100 ℃, wherein the room temperature is from about 18 to about 25 ℃.

The reaction formula of the preparation method of the polyarylene sulfide is as follows:

the reaction formula according to an embodiment of the present invention is shown below. Thioanisole (thioanisole) and methyl phenyl sulfoxide (methylphenylsulfoxide) are reacted under an acidic condition to obtain a cationic intermediate with sulfonium group (sulfonium group). Next, an appropriate amount of an oxidizing agent is used to selectively oxidize the thioether group instead of the sulfonium group, as shown in reaction formula (III). Then, the polyarylene sulfide monomer is obtained after demethylation. Finally, the polyarylene sulfide monomer is polymerized as shown in the reaction formula (IV)

According to the embodiment of the present invention, the reaction mechanism of the above oxidation step is shown in the following reaction formula, wherein the cationic thioether intermediate (cationic thioether intermediate) is oxidized by acetic acid peroxide (acetic peroxide) to obtain cationic sulfoxide intermediate (cationic sulfoxide intermediate). The acetic acid peroxide (acetic peroxide) can be obtained by mixing hydrogen peroxide and acetic acid (acetic acid).

The acetic acid peroxide (acetic peroxide) may be prepared by mixing hydrogen peroxide and acetic acid (acetic acid). The resulting acetic acid peroxide may then be used to oxidize a cationic thioether intermediate. The positive charges on the methyl and sulfonic groups provide steric and electrical resistance (steric and electrical barrier) to selectively oxidize the thioether groups. In other words, the positive charge on the sulfonium group and a steric barrier group (i.e., alkyl group) can prevent the sulfonium group from being oxidized by one or more oxidizing agents.

Suitable oxidizing agents can selectively oxidize the thioether group without oxidizing the sulfonium group to obtain an intermediate of polyarylene sulfide monomer. Next, the polyarylene sulfide monomer may be prepared by demethylating the sulfonium group.

In contrast, the known processes do not make use of selective oxidation, since the known processes use oxidizing agents, such as halogens (halogen), which are different from the present invention. However, it is known that the oxidation mode using halogen may cause the oxidation of the sulfonium group (sulfonium group). To avoid the problems of the known methods, the oxidation method described in the examples of the present invention does not use halogens.

In addition, unlike known methods, the embodiments of the present invention employ an oxidation step prior to the demethylation step. In contrast, it is known to carry out the oxidation step after the demethylation step.

In order to make the aforementioned and other objects, features and advantages of the present invention comprehensible, several embodiments accompanied with figures are described in detail below: