KR20200036326A - Method for praparing polyarylene sulfide - Google Patents

Abstract

The present invention relates to a method for manufacturing low chlorine polyarylene sulfide. According to the method of the present invention, the present invention relates to the method for manufacturing low chlorine polyarylene sulfide, in which, after polymerization of the polyarylene sulfide, instead of adding only water, an existing phase separation agent, a phase separation agent containing an additive for substituting a polyarylene sulfide end group and water is added, thereby being able to improve processability by effectively removing chlorine of the polyarylene sulfide end group.

Description

Manufacturing method of polyarylene sulfide {METHOD FOR PRAPARING POLYARYLENE SULFIDE}

The present invention relates to a method for producing polyphenylene sulfide capable of reducing the chlorine content of end groups in a simple manner.

Polyarylene sulfide (PAS), typified by polyphenylene sulfide (PPS), is used in metals, especially aluminum or zinc, in automobiles, electrical and electronic products, machinery, etc. due to its excellent strength, heat resistance, flame retardancy and processability. It is widely used as a material to replace the same die casting metal. Particularly, in the case of PPS resin, since it has good fluidity, it is advantageous to use it as a compound by kneading with a filler or reinforcing agent such as glass fiber.

In general, PAS is produced by polymerizing a sulfur source and a dihalogenated aromatic compound under polymerization conditions in the presence of an amide-based compound such as N-methyl pyrrolidone (NMP), and optionally a molecular weight modifier such as an alkali metal salt is further used. do.

These PASs contain chlorine in the end groups, and when the chlorine content is high, the chlorine content needs to be reduced to meet the low chlorine standard because it does not satisfy the low chlorine content standard currently required for plastics applied to electronic products.

Therefore, in order to reduce the chlorine content of the PAS, there is a method of reducing the end group chlorine by reacting a substance capable of binding to the end group of the PAS with the PAS already polymerized. However, the method is complicated and difficult to apply in practice.

As another method, during the polymerization reaction (for example, before shear polymerization, after shear polymerization, after polymerization after polymerization, after adding a phase separation agent), a method of adding an alcohol, thiol-based or amine-based PPS end group-substitution material, respectively However, it is difficult to actually apply the additional reaction in the high temperature and high pressure reaction step.

The present invention effectively reduces the chlorine content of the terminal group of the polyarylene sulfide without the additional step of adding an additive for the chlorine substitution of the terminal group of the polyarylene sulfide, which can satisfy the low chlorine standard required for plastics for electronic products. It is intended to provide a method for manufacturing len sulfide.

According to one embodiment of the invention, the alkali metal hydroxide and alkali metal hydroxide are dehydrated in the presence of an organic acid salt of an alkali metal in a mixed solvent of water and an amide compound to cause sulfide of the alkali metal, and water and an amide system. A first step of preparing a sulfur source comprising a mixed solvent of a compound;

A second step of preparing a polyarylene sulfide by polymerization reaction by adding a dihalogenated aromatic compound and an amide compound to the reactor containing the sulfur source; And

Including the third step of removing the chlorine of the polyarylene sulfide end group by adding a phase separation agent including water and an additive for substituting the polyarylene sulfide end group to the reactor of the second step in which the polymerization reaction is completed. ,

The polyarylene sulfide end group substitution additive provides a method for producing polyarylene sulfide comprising at least one aromatic salt compound selected from compounds represented by the following Chemical Formulas 1 and 2.

[Formula 1]

Ar ₁ -SM ₁

[Formula 2]

M ₂ COO-Ar ₂ -SH

(In the above formula, Ar ₁ is aryl having 6 to 60 carbon atoms, Ar ₂ is arylene having 6 to 60 carbon atoms, M ₁ And M ₂ are each independently an alkali metal)

In the present invention, instead of the process of adding general water in the process of adding a phase separating agent to precipitate polyarylene sulfide after post-polymerization of polyarylene sulfide, a specific terminal group-displaceable additive is dissolved in water as a phase separating agent and used together. . Using this method, polyarylene sulfide can be precipitated and separated, and at the same time, the chlorine content of the polyarylene sulfide end group can be effectively lowered without additionally adding an additional end group substitution substance during polyarylene sulfide polymerization. It is possible to provide a polyarylene sulfide that satisfies the low chlorine standard required for plastics for electronic products.

1 is a simplified illustration of a method for producing polyarylene sulfide according to an embodiment of the present invention.
FIG. 2 is a schematic diagram showing a method for preparing polyarylene sulfide of Comparative Example 1.
3 is a schematic view showing a method for preparing the polyarylene sulfides of Comparative Examples 2 to 5.

In the present invention, terms such as first and second are used to describe various components, and the terms are used only for the purpose of distinguishing one component from another component.

In addition, the terms used in this specification are only used to describe exemplary embodiments, and are not intended to limit the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise. In this specification, the terms "include", "have" or "have" are intended to indicate the presence of implemented features, numbers, steps, elements or combinations thereof, one or more other features or It should be understood that the existence or addition possibilities of numbers, steps, elements, or combinations thereof are not excluded in advance.

The present invention can be applied to various changes and may have various forms, and specific embodiments will be illustrated and described in detail below. However, this is not intended to limit the present invention to a specific disclosure form, and it should be understood that all modifications, equivalents, and substitutes included in the spirit and scope of the present invention are included.

Hereinafter, a method for manufacturing polyarylene sulfide according to a specific embodiment of the present invention will be described in more detail.

According to one embodiment of the invention, the alkali metal hydroxide and alkali metal hydroxide are dehydrated in the presence of an organic acid salt of an alkali metal in a mixed solvent of water and an amide compound to cause sulfide of the alkali metal, and water and an amide system. A first step of preparing a sulfur source comprising a mixed solvent of a compound;

A second step of preparing a polyarylene sulfide by polymerization reaction by adding a dihalogenated aromatic compound and an amide compound to the reactor containing the sulfur source; And

Including the third step of removing the chlorine of the polyarylene sulfide end group by adding a phase separation agent including water and an additive for substituting the polyarylene sulfide end group to the reactor of the second step in which the polymerization reaction is completed. ,

The polyarylene sulfide end group substitution additive may be provided with a method for preparing a low-chlorine polyarylene sulfide comprising at least one aromatic salt compound selected from compounds represented by the following Chemical Formulas 1 and 2.

[Formula 1]

Ar ₁ -SM ₁

[Formula 2]

M ₂ COO-Ar ₂ -SH

(In the above formula, Ar ₁ is aryl having 6 to 60 carbon atoms, Ar ₂ is arylene having 6 to 60 carbon atoms, M ₁ And M ₂ are each independently an alkali metal)

In the present invention, in the process of adding the phase-separating agent (water) added last during the polyphenylene sulfide polymerization reaction, the salt of the terminal-substitution-substituting material is used together with the phase-separating agent (water), and an additional step of adding the terminal-substitution substance It relates to a method that can easily produce low-chlorinated polyphenylene sulfide without the presence of chlorine.

1 is a simplified illustration of a method for producing polyarylene sulfide according to an embodiment of the present invention.

As shown in FIG. 1, the present invention proceeds a dehydration reaction using raw material components for preparing polyarylene sulfide, and conducts front-end and rear-end polymerization using a dihalogenated aromatic compound, followed by polyarylene sulfide ends An aqueous solution containing an additive capable of displacing chlorine and water is added as a phase separator. The present invention can provide a low-chlorine PPS by removing the Cl of the terminal group of the PPS without the addition of additional substances by the phase separation agent input.

In the method for preparing the polyarylene sulfide according to one embodiment of the present invention, each step will be described.

The first step described above is a step of preparing a sulfur source.

The sulfur source is prepared by performing dehydration of an alkali metal hydroxide, an alkali metal hydroxide and an acidic compound in a mixed solvent of water and an amide compound. Accordingly, the sulfur source may include a mixed solvent of water and an amide compound remaining after the dehydration reaction, together with the sulfide of the alkali metal produced by the reaction of the alkali metal hydroxide and the hydroxide of the alkali metal.

Subsequently, in the present invention, a polyarylene sulfide having excellent yield is produced through polymerization by continuously using the sulfur source, a dihalogenated aromatic compound, and an amide compound.

The sulfide of the alkali metal may be determined according to the type of the alkali metal hydrosulfide used in the reaction, and specific examples include lithium sulfide, sodium sulfide, potassium sulfide, rubidium sulfide, or cesium sulfide. Mixtures of two or more can be included.

When preparing a sulfur source by the reaction of the alkali metal hydroxide and the hydroxide of the alkali metal, specific examples of the alkali metal hydrosulfide include lithium hydrogen sulfide, sodium hydrogen sulfide, potassium hydrogen sulfide, rubidium hydrogen sulfide, or cesium hydrogen sulfide. have. Any one or a mixture of two or more of these may be used, and anhydrides or hydrates of these may also be used.

In addition, specific examples of the alkali metal hydroxide include lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, or cesium hydroxide, and any one or a mixture of two or more thereof may be used. The hydroxide of the alkali metal may be used in an equivalent ratio of 0.90 to 2.0, more specifically in an equivalent ratio of 1.0 to 1.5, and more specifically in an equivalent ratio of 1.0 to 1.1, per 1 equivalent of the sulfide of the alkali metal.

On the other hand, in the present invention, equivalent weight means molar equivalent weight (eq / mol).

In addition, when preparing the sulfur source by the reaction of the alkali metal hydroxide and the hydroxide of the alkali metal, the organic acid salt of the alkali metal is used together to accelerate the polymerization reaction as a polymerization aid to increase the polymerization degree of the polyarylene sulfide in a short time. Input. Specifically, the organic acid salt of the alkali metal may be lithium acetate or sodium acetate, and any one or a mixture of two or more of them may be used. The organic acid salt of the alkali metal may be used in an equivalent ratio of 0.01 to 1.0, more specifically 0.01 to 0.8, and even more specifically 0.05 to 0.5 based on 1 equivalent of the hydrosulfide of the alkali metal.

The reaction of the alkali metal hydroxide with an alkali metal hydroxide may be performed in a mixed solvent of water and an amide compound, wherein specific examples of the amide compound are N, N-dimethylformamide or N, N -Amide compounds such as dimethylacetamide; Pyrrolidone compounds such as N-methyl-2-pyrrolidone (NMP) or N-cyclohexyl-2-pyrrolidone; Caprolactam compounds such as N-methyl-ε-caprolactam; Imidazolidinone compounds such as 1,3-dialkyl-2-imidazolidinone; Urea compounds such as tetramethyl urea; Or phosphate amide compounds such as hexamethylphosphate triamide, and any one or a mixture of two or more of them can be used. Among these, the amide-based compound may be more specifically N-methyl-2-pyrrolidone (NMP) in consideration of reaction efficiency and cosolvent effect as a polymerization solvent during polymerization for polyarylene sulfide production.

In the first step, the amide compound may be used in an amount of about 1.0 to about 2.0 equivalents, or about 1.3 to 2.0 equivalents, or about 1.35 to 1.65 equivalents based on 1 equivalent of the hydrosulfide of the alkali metal. The content of the amide-based compound in the first step can be used in the range as described above in terms of effectively forming the compound with the sulfur compound formed through the dehydration process, and thereby effectively performing the subsequent polymerization process.

In addition, in the first step, water may be used in an equivalent ratio of 1 to 8 based on 1 equivalent of the amide compound, more specifically 1.5 to 5, and more specifically 2.5 to 4.5.

On the other hand, in the first step, a reactant containing an alkali metal hydrosulfide and an alkali metal hydroxide may generate sulfide of an alkali metal through dehydration. At this time, the dehydration reaction may be performed by stirring at a rate of about 100 to 500 rpm in a temperature range of about 130 to 220 ° C. More specifically, it may be performed by stirring at a rate of about 100 to 300 rpm in a temperature range of about 175 to 215 ° C. At this time, the time of the dehydration reaction may be performed within about 30 minutes to 6 hours, or about 1 hour to 3 hours.

During the dehydration process, a solvent such as water may be removed through distillation, etc., and a part of the amide compound is discharged together with water, and some sulfur contained in the sulfur source reacts with water by heat during the dehydration process. It can be volatilized as a hydrogen sulfide gas. In this case, hydroxide of the same mole of alkali metal as the hydrogen sulfide may be generated.

In particular, in the dehydration liquid generated during the dehydration reaction in the first step, that is, in the dehydration liquid that is removed to the outside during the dehydration process, the total volume of the total mixture containing a mixed solvent of water and an amide compound Based on the amide compound may be included in 25% to 35% (v / v).

On the other hand, as a result of the reaction of the alkali metal hydroxide, alkali metal hydroxide and alkali metal salt, the alkali metal sulfide is precipitated in a solid phase in a mixed solvent of water and an amide compound, and in the reaction system, unreacted alkali metal Some sulfide may remain. Accordingly, when a polyarylene sulfide according to the present invention is used as a sulfur source, when a sulfur source prepared by reacting the above-mentioned alkali metal hydrosulfide with an alkali metal hydroxide is used, the molar ratio of the sulfur source is alkali precipitated as a result of the reaction. It means the total molar ratio of the sulfide of the metal and the unreacted alkali metal hydrosulfide.

Subsequently, a dehydration process may be additionally performed to remove a solvent such as water in the reaction product containing sulfides of alkali metals produced as a result of the reaction described above. The dehydration process can be performed according to a method well known in the art, the conditions are not greatly limited, and specific process conditions are as described above.

In addition, during the dehydration process, the sulfur contained in the sulfur source reacts with water to generate hydrogen sulfide and alkali metal hydroxide, and the hydrogen sulfide produced is volatilized, and thus remains in the system after the dehydration process by hydrogen sulfide volatilized out of the system during the dehydration process. The amount of sulfur in the sulfur source can be reduced. For example, when using a sulfur source containing alkali metal hydrosulfide as a main component, the amount of sulfur remaining in the system after the dehydration process is equal to a value obtained by subtracting the molar amount of hydrogen sulfide volatilized out of the system from the molar amount of sulfur in the input sulfur source. . Accordingly, it is necessary to quantify the amount of effective sulfur contained in the sulfur source remaining in the system after the dehydration process from the amount of hydrogen sulfide volatilized out of the system. Specifically, the dehydration process may be performed until water becomes a molar ratio of 1 to 5, more specifically 1.5 to 4, and more specifically 2.0 to 3.5 with respect to 1 mole of effective sulfur. When the amount of moisture in the sulfur source is excessively reduced by the dehydration process, water can be adjusted by adding water prior to the polymerization process.

Accordingly, the sulfur source prepared by the reaction and dehydration of the alkali metal hydroxide and the alkali metal hydroxide may include a mixed solvent of water and an amide compound, together with the alkali metal sulfide, The water may be specifically included in a molar ratio of 2.5 to 3.5 with respect to 1 mole of sulfur contained in the sulfur source. In addition, the sulfur source may further include an alkali metal hydroxide produced by the reaction of sulfur and water.

Meanwhile, according to one embodiment of the present invention, the second step is a step of preparing a polyarylene sulfide by polymerizing the sulfur source with a dihalogenated aromatic compound.

The dihalogenated aromatic compound usable for the preparation of the polyarylene sulfide is a compound in which two hydrogens in the aromatic ring are substituted with halogen atoms, and specific examples include o-dihalobenzene, m-dihalobenzene, and p-dihal Robenzene, dihalotoluene, dihalonaphthalene, dihalobiphenyl, dihalobenzoic acid, dihalodiphenyl ether, dihalodiphenylsulfone, dihalodiphenylsulfoxide or dihalodiphenyl ketone, etc. Mixtures of two or more can be used. In the dihalogenated aromatic compound, the halogen atom may be fluorine, chlorine, bromine or iodine. Of these, p-dichlorobenzene (p-DCB) may also be used when considering the effect of reducing reactivity and side reaction production when preparing polyarylene sulfide.

The dihalogenated aromatic compound may be added in an amount of 0.8 to 1.2 equivalents. When it is added within the above-mentioned content range, polyarylene sulfide having excellent physical properties can be prepared without fear of a decrease in the melt viscosity of the polyarylene sulfide produced and an increase in the chlorine content present in the polyarylene sulfide. have. Considering the superiority of the improvement effect according to the sulfur source and the control amount of the dihalogenated aromatic compound, more specifically, the dihalogenated aromatic compound may be added in an equivalent weight of 0.8 to 1.1.

In addition, before proceeding to the second step, it may further comprise the step of lowering the temperature of the reactor containing the sulfur source to a temperature of 150 to 200 ℃ to prevent the vaporization of the dihalogenated aromatic compound.

In addition, the polymerization reaction of the above-mentioned sulfur source with a dihalogenated aromatic compound is an aprotic polar organic solvent, and can be performed in a solvent of an amide-based compound that is stable to alkali at high temperatures.

Specific examples of the amide-based compound are as described above, and when considering reaction efficiency among the exemplified compounds, more specifically, the amide-based compound is N-methyl-2-pyrrolidone (NMP) or N-cyclo It may be a pyrrolidone compound such as hexyl-2-pyrrolidone.

Since the amide compound contained in the sulfur source in the first step may act as a cosolvent, the amide compound added in the second step is a molar ratio of water (H ₂ O) to the amide compound present in the polymerization reaction system. It can be added in an amount such that the (molar ratio of water / amide compound) is 0.85 or more.

Meanwhile, the dihalogenated aromatic compound usable for the production of the polyarylene sulfide is a compound in which two hydrogens in the aromatic ring are substituted with halogen atoms, and specific examples include o-dihalobenzene, m-dihalobenzene, and p -Dihalobenzene, dihalotoluene, dihalonaphthalene, dihalobiphenyl, dihalobenzoic acid, dihalodiphenyl ether, dihalodiphenylsulfone, dihalodiphenylsulfoxide or dihalodiphenyl ketone. One or two or more mixtures may be used. In the dihalogenated aromatic compound, the halogen atom may be fluorine, chlorine, bromine or iodine. Of these, p-dichlorobenzene (p-DCB) may also be used when considering the effect of reducing reactivity and side reaction production when preparing polyarylene sulfide.

The dihalogenated aromatic compound may be added in an amount of about 0.8 to 1.2 based on 1 equivalent of the hydrosulfide of the alkali metal. When it is added within the above-mentioned content range, polyarylene sulfide having excellent physical properties can be prepared without fear of a decrease in the melt viscosity of the polyarylene sulfide produced and an increase in the chlorine content present in the polyarylene sulfide. have. Considering the superiority of the improvement effect according to the sulfur source and the control amount of the dihalogenated aromatic compound, more specifically, the dihalogenated aromatic compound may be added in an equivalent weight of about 0.9 to 1.1.

In addition, before proceeding to the second step, it may further include the step of lowering the temperature of the reactor containing the sulfur source to a temperature of less than 200 ℃ above 150 ℃ in order to prevent the vaporization of the dihalogenated aromatic compound.

In addition, other additives for controlling the polymerization reaction or molecular weight, such as a molecular weight modifier and a crosslinking agent, may be further added in a content within a range that does not degrade the physical properties and production yield of the final polyarylene sulfide.

The polymerization reaction of the sulfur source and the dihalogenated aromatic compound may be performed at about 200 to 300 ° C. Alternatively, it may be performed in multiple steps while changing the temperature within the above-described temperature range. Specifically, after the first polymerization reaction at about 200 ° C or more and less than about 250 ° C, the second polymerization reaction is performed at a temperature higher than the temperature at the time of the first polymerization, specifically, at about 250 ° C to 300 ° C. You can.

Meanwhile, according to one embodiment of the present invention, the third step is a chlorine removal step of the end group of the polyarylene sulfide.

The reaction product generated as a result of the polymerization reaction in the second step is separated into an aqueous phase and an organic phase, and the polyarylene sulfide, which is a polymerization reaction product, is dissolved in the organic phase. Accordingly, a process for precipitation and separation of the prepared polyarylene sulfide may be selectively performed.

At this time, the present invention, in the process of separating and separating the polyarylene sulfide, the process of reducing the content by substituting the chlorine of the end group of the polyarylene sulfide can be simultaneously performed.

Specifically, the present invention does not use a separate additive during the polymerization process to reduce the chlorine content of the end groups as in the prior art, and also does not use only water as a phase separation agent. The present invention is characterized in that an aqueous solution in which a certain amount of a polyarylene sulfide end group substitution additive is dissolved in water serving as a phase separation is used as a phase separation agent.

The phase separation agent is introduced into the reactor in which the polymerization in the second step is completed, thereby replacing chlorine in the end group of the polyarylene sulfide contained in the polymerization reaction mixture and reducing the content thereof, and simultaneously depositing polyarylene sulfide. And the separation process can be performed.

Therefore, after the phase separation agent is added, the organic phase may contain the low-chlorine polyarylene sulfide of the present invention, and the present invention can more easily replace the chlorine at the end of the polyarylene sulfide.

It is preferable that the additive for substituting the polyarylene sulfide end group includes at least one aromatic salt compound selected from compounds represented by the following Chemical Formulas 1 and 2.

[Formula 1]

Ar ₁ -SM ₁

[Formula 2]

M ₂ COO-Ar ₂ -SH

(In the above formula, Ar ₁ is aryl having 6 to 60 carbon atoms, Ar ₂ is arylene having 6 to 60 carbon atoms, M ₁ And M ₂ are each independently an alkali metal)

That is, examples of the additive for substituting a polyarylene sulfide end group according to the present invention may basically include a lithium salt of thiophenolate, sodium salt, potassium salt, rubidium salt, cesium salt, and the like. In addition, in another example, the additive has a structure such as Ar-SLi, Ar-SNa, Ar-SK, Ar-SRb, Ar-SCs, or LiCOO-Ar-SH, NaCOO-Ar-SH, KCOO-Ar It may have a structure such as -SH, RbCOO-Ar-SH, CsCOO-Ar-SH, or the like.

Preferably, in Chemical Formula 1, Ar ₁ is aryl having 6 to 10 carbon atoms, and M ₁ may be preferably Li or Na.

In addition, in Chemical Formula 2, Ar ₂ may be arylene having 6 to 10 carbon atoms, and M ₂ may be preferably Li or Na.

In addition, it is preferable that the phase-separating agent includes an additive for substituting a polyarylene sulfide end group of 0.5 to 10 mol%. If the content of the additive is less than 0.5 mol%, there is a problem that the substitution of end group chlorine is not well achieved, and if it exceeds 10 mol%, there is a problem that the PPS decomposes and the molecular weight of the PPS is insufficient.

In addition, the content of the phase-separating agent can be carried out by adding to the reaction mixture and cooling in an equivalent ratio of 1 to 5 with respect to 1 equivalent of sulfur. When the aqueous phase separation agent is added in the above-described content range, polyarylene sulfide can be precipitated with excellent efficiency.

On the other hand, for the polyarylene sulfide precipitated in the above process, washing and filtration drying processes may be selectively performed according to a conventional method.

The specific method for manufacturing the polyarylene sulfide may refer to Examples described later. However, the manufacturing method of polyarylene sulfide is not limited to the contents described in the present specification, and the manufacturing method may further employ the steps conventionally employed in the technical field to which the present invention pertains, and The step (s) can be changed by conventionally changeable step (s).

On the other hand, by the method of manufacturing a low-chlorinated polyarylene sulfide according to an embodiment of the present invention as described above, while showing thermal properties equal to or higher than the conventional, it is possible to easily produce a polyarylene sulfide excellent in yield.

Specifically, the polyarylene sulfide produced by the above production method is produced in a yield of about 83% or more, or about 84% or more, or about 84.5% or more, and a 5 kg load condition according to the method of ASTM D 1238-10. The melt mass flow rate (MFR) measured below may be about 200 to 1000 g / 10min, or about 250 to 900 g / 10min, about 280 to 800 g / 10min, and about 300 to 700 g / 10min. In particular, the melt mass flow rate (MFR) may be maintained in the above-mentioned range in terms of improving processability in using the polyarylene sulfide by injection molding.

In addition, the polyarylene sulfide may have a melting temperature (T _m ) of about 270 to 300 ° C and a crystallization temperature (T _c ) of about 180 to 250 ° C. In addition, the polyarylene sulfide may have a weight average molecular weight (Mw) of greater than 10,000 g / mol and less than 30,000 g / mol.

In particular, the low-chlorine polyarylene sulfide according to the present invention may have a chlorine content of 1500 ppm or less measured by X-ray fluorescence (XRF) analysis.

Hereinafter, preferred embodiments are provided to help understanding of the present invention. However, the following examples are only provided to more easily understand the present invention, and the contents of the present invention are not limited thereby.

Example  One

As shown in the method of Figure 1, a low-chlorine PPS was prepared through a process of dissolving an end-group substitutable additive of PPS in water and using it as a phase separation agent.

(1) Dehydration reaction (first step)

Sodium sulfide (Na ₂ S) was prepared by mixing 1.00 equivalents of sodium hydrogen sulfide (NaSH) and 1.05 equivalents (eq) of sodium hydroxide (NaOH) in a reactor. At this time, 0.44 equivalents of sodium acetate (CH ₃ COONa) powder, 1.65 equivalents of N-methyl-2-pyrrolidone (NMP) and 4.72 equivalents of deionized water (DI water) were added to the reactor. At this time, the solid reagent was first added and then added in the order of NMP and DI water. First, the reactor was made into a nitrogen atmosphere, and then the nitrogen line was removed. When the dehydration valve is slowly opened and heated up, dehydration starts to come out from inside the reactor. The dehydration reaction is performed by liquefying through a condenser and then collecting. The residual mixture obtained through the above process was obtained as a sulfur source.

(2) polymerization reaction (second step)

When the temperature of the reactor including the sulfur supply source obtained through the dehydration reaction is raised and the temperature reaches 175 ° C., 1.04 equivalent of para-dichlorobenzene (p-DCB) dissolved in 1.35 equivalent of NMP is quantitatively pumped. It was introduced into the reactor.

When the p-DCB was inputted, the reactor temperature was controlled to perform shear polymerization and rear polymerization. That is, the temperature inside the reactor was maintained at 160 ° C for 10 minutes to stabilize, and the temperature was raised to 230 ° C and maintained for 2 hours to proceed polymerization (shear polymerization). Subsequently, the temperature was further raised to 255 ° C. for 15 minutes, and then maintained for 2 hours to proceed polymerization (post polymerization).

(3) Chlorine removal of PPS end group and PPS precipitation and separation step (3rd step)

Sodium thiophenolate (sodium thiophenolate) was added to the water 1 mol% to prepare a phase separation agent in aqueous solution in advance.

After the post-stage polymerization, the phase separation agent was added to the reactor, the temperature of the reactor was lowered to room temperature while stirring was performed, and the obtained slurry was washed with an organic solvent and water.

That is, the slurry was sequentially washed with deionized water and a mixture of NMP (mixed volume ratio = 1: 1) and deionized water, filtered, and then filtered with a 0.4% acetic acid aqueous solution at 90 ° C. After washing at 50 ° C with acetone, filtered, and then washed with deionized water at 90 ° C until the pH reached 7 times and filtered. The washed polyphenylene sulfide was recovered after drying at 150 ° C. for 5 hours in a vacuum oven to prepare polyphenylene sulfide with reduced chlorine at the end group (yield 85%).

Example  2

In the third step of Example 1, in the same manner as in Example 1, except that an aqueous solution in which 1 mol% of sodium thiosalicylic acid was added instead of sodium thiophenolate was used. Short-term chlorine-reduced polyphenylene sulfide was prepared (yield 84%).

Comparative example  One

As shown in the method of FIG. 2, PPS was prepared without input of a PPS end group substitution additive. FIG. 2 is a schematic diagram showing a method for preparing polyarylene sulfide of Comparative Example 1.

(1) Dehydration reaction (first step)

Sodium sulfide (Na ₂ S) was prepared by mixing 1.00 equivalents of sodium hydrogen sulfide (NaSH) and 1.05 equivalents (eq) of sodium hydroxide (NaOH) in a reactor. At this time, 0.44 equivalents of sodium acetate (CH ₃ COONa) powder, 1.65 equivalents of N-methyl-2-pyrrolidone (NMP) and 4.72 equivalents of deionized water (DI water) were added to the reactor. At this time, the solid reagent was first added and then added in the order of NMP and DI water. First, the reactor was made into a nitrogen atmosphere, and then the nitrogen line was removed. When the dehydration valve is slowly opened and heated up, dehydration starts to come out from inside the reactor, and dehydration reaction is carried out by liquefying through a condenser. The residual mixture obtained through the above process was obtained as a sulfur source.

(2) polymerization reaction (second step)

When the temperature of the reactor including the sulfur supply source obtained through the dehydration reaction is raised and the temperature reaches 175 ° C., 1.04 equivalent of para-dichlorobenzene (p-DCB) dissolved in 1.35 equivalent of NMP is quantitatively pumped. It was introduced into the reactor.

When the p-DCB was inputted, the reactor temperature was controlled to perform shear polymerization and rear polymerization. That is, the temperature inside the reactor was maintained at 160 ° C for 10 minutes to stabilize, and the temperature was raised to 230 ° C and maintained for 2 hours. Subsequently, the temperature was raised to 255 ° C for 15 minutes, and then maintained for 2 hours.

(3) PPS precipitation and separation process

To the reactor that passed through the second step, a phase separation agent (water) was added and the temperature of the reactor was lowered to room temperature while stirring was performed, and then the resulting slurry was washed with an organic solvent and water.

The slurry was washed sequentially with a mixture of deionized water and NMP (mixed volume ratio = 1: 1), and deionized water, filtered, and then washed with a 0.4% acetic acid aqueous solution at 90 ° C. and filtered with acetone. After washing at 50 ° C., filtering was performed, followed by washing with deionized water at 90 ° C. until the pH reached 7, followed by filtering. The washed polyphenylene sulfide was dried in a vacuum oven at 150 ° C. for 5 hours, and then recovered to prepare polyphenylene sulfide (yield 85%).

Comparative example  2

In the method of FIG. 3, PPS was prepared by adding thiophenol after shear polymerization after p-DCB injection. 3 is a schematic view showing a method for preparing the polyarylene sulfides of Comparative Examples 2 to 5.

(1) Dehydration reaction (first step)

Sodium sulfide (Na ₂ S) was prepared by mixing 1.00 equivalents of sodium hydrogen sulfide (NaSH) and 1.05 equivalents (eq) of sodium hydroxide (NaOH) in a reactor. At this time, 0.44 equivalents of sodium acetate (CH ₃ COONa) powder, 1.65 equivalents of N-methyl-2-pyrrolidone (NMP) and 4.72 equivalents of deionized water (DI water) were added to the reactor. At this time, the solid reagent was first added and then added in the order of NMP and DI water. First, the reactor was made into a nitrogen atmosphere, and then the nitrogen line was removed. When the dehydration valve is slowly opened and heated up, dehydration starts to come out from inside the reactor. The dehydration reaction is performed by liquefying through a condenser and then collecting. The residual mixture obtained through the above process was obtained as a sulfur source.

(2) polymerization reaction (second step)

When the temperature of the reactor including the sulfur supply source obtained through the dehydration reaction is raised and the temperature reaches 175 ° C, 1.04 equivalent of para-dichlorobenzene (p-DCB) dissolved in 1.35 equivalent of NMP is measured using a quantitative pump. It was introduced into the reactor.

After the p-DCB was introduced, 1 mol% of thiophenol was added. After the input of the thiophenol, the reactor temperature was controlled to perform shear polymerization and rear polymerization. That is, the temperature inside the reactor was maintained at 160 ° C for 10 minutes to stabilize, and the temperature was raised to 230 ° C and maintained for 2 hours. Subsequently, the temperature was raised to 255 ° C for 15 minutes, and then maintained for 2 hours.

(3) PPS precipitation and separation process

To the reactor that passed through the second step, a phase separation agent (water) was added and the temperature of the reactor was lowered to room temperature while stirring was performed, and then the resulting slurry was washed with an organic solvent and water.

The slurry was washed sequentially with a mixture of deionized water and NMP (mixed volume ratio = 1: 1), and deionized water, filtered, and then washed with a 0.4% acetic acid aqueous solution at 90 ° C. and filtered with acetone. After washing at 50 ° C., filtering was performed, followed by washing with deionized water at 90 ° C. until the pH reached 7, followed by filtering. The washed polyphenylene sulfide was recovered in a vacuum oven after drying at 150 ° C. for 5 hours to prepare polyphenylene sulfide (yield 86%).

Comparative example  3

In the method of Figure 3, after the end of the shear polymerization, thiophenol (thiophenol) was added and the subsequent polymerization was performed to prepare PPS.

(1) Dehydration reaction (first step)

Sodium sulfide (Na ₂ S) was prepared by mixing 1.00 equivalents of sodium hydrogen sulfide (NaSH) and 1.05 equivalents (eq) of sodium hydroxide (NaOH) in a reactor. At this time, 0.44 equivalents of sodium acetate (CH ₃ COONa) powder, 1.65 equivalents of N-methyl-2-pyrrolidone (NMP) and 4.72 equivalents of deionized water (DI water) were added to the reactor. At this time, the solid reagent was first added and then added in the order of NMP and DI water. First, the reactor was made into a nitrogen atmosphere, and then the nitrogen line was removed. When the dehydration valve is slowly opened and heated up, dehydration starts to come out from inside the reactor. The dehydration reaction is performed by liquefying through a condenser and then collecting. The residual mixture obtained through the above process was obtained as a sulfur source.

(2) polymerization reaction (second step)

When the temperature of the reactor including the sulfur supply source obtained through the dehydration reaction is raised and the temperature reaches 175 ° C, 1.04 equivalent of para-dichlorobenzene (p-DCB) dissolved in 1.35 equivalent of NMP is measured using a quantitative pump. It was introduced into the reactor.

When the p-DCB was added, the temperature inside the reactor was maintained at 160 ° C for 10 minutes to stabilize, and the temperature was raised to 230 ° C and maintained for 2 hours.

At this time, 1 mol% of thiophenol was dissolved in NMP and introduced into the reactor. When the input of the thiophenol was completed, the temperature was raised to 255 ° C for 15 minutes, and then maintained for 2 hours.

(3) PPS precipitation and separation process

To the reactor that passed through the second step, a phase separation agent (water) was added and the temperature of the reactor was lowered to room temperature while stirring was performed, and then the resulting slurry was washed with an organic solvent and water.

The slurry was washed sequentially with a mixture of deionized water and NMP (mixed volume ratio = 1: 1), and deionized water, filtered and then washed with a 0.4% acetic acid aqueous solution at 90 ° C. and filtered again with acetone. After washing at 50 ° C., filtering was performed, followed by washing with deionized water at 90 ° C. until the pH reached 7, followed by filtering. The washed polyphenylene sulfide was recovered in a vacuum oven after drying at 150 ° C. for 5 hours to prepare polyphenylene sulfide (yield 85%).

Comparative example  4

In the second step of Comparative Example 2, polyphenylene sulfide was prepared in the same manner as in Comparative Example 2, except that an aqueous solution in which 1 mol% of sodium thiophenolate was added instead of thiophenol was used. (Yield 84%)

Comparative example  5

In the second step of Comparative Example 3, polyphenylene sulfide was prepared in the same manner as in Comparative Example 3, except that an aqueous solution in which 1 mol% of sodium thiophenolate was added instead of thiophenol was used. (Yield 85%)

Test example  One

For the polyphenylene sulfide prepared in Examples and Comparative Examples, physical properties and chlorine content of end groups were measured in the following manner, and the results are shown in Table 1 below.

1) Yield: After measuring the weight of the dried polyphenylene sulfide (PPS) on an electronic balance, the number of moles was calculated based on the repeat unit value (108.16 g / mol). This yielded the yield (mol / mol%) of the polymer actually recovered on the basis of the number of moles of sodium sulfide or para-dichlorobenzene injected less.

In particular, in order to measure the yield more accurately, in order to wash the polyphenylene sulfide (PPS) slurry obtained after polymerization, it is diluted with water at room temperature and then simply filtered through a sieve to dissolve well in the organic solvent in the slurry or water at high temperature. It does not apply the conventional method of measuring the yield without completely removing the soluble substances from the product. After washing at least three times in hot washing water and hot organic solvent, drying in a hot vacuum oven for one day, yield It was measured.

2) Melt Mass Flow Rate (MFR): Melt Flow Rate (MFR) of polyphenylene sulfide resins prepared through Examples and Comparative Examples was measured according to the method of ASTM D1238-10.

At this time, using a Gottfert MI-4 apparatus, each polyphenylene sulfide resin was placed under a load condition of 315 ° C. and 5 kg, and the melted material was weighed against timed segments of the extrudate and g The extrusion rate was calculated in / 10min increments and calculated.

3) PPS terminal Cl content (ppm)

The content of Cl contained in PPS was measured using a dispersive X-ray fluorescence spectrometer (ED-XRF; Energy Dispersive X-ray Fluorescence).

PPS end group substitution additive PPS end group substitution additive input timing MFR (g / 10min) Cl (ppm) Example 1 Sodium thiophenolate Simultaneous input with phase separator 565 1215 Example 2 Sodium thiosalicylic acid Simultaneous input with phase separator 624 1422 Comparative Example 1 none none 573 2502 Comparative Example 2 Thiophenol Before shear polymerization 956 2215 Comparative Example 3 Thiophenol After shear polymerization 857 2729 Comparative Example 4 Sodium thiophenolate Before shear polymerization 725 2125 Comparative Example 5 Sodium thiophenolate After shear polymerization 792 1897

In Table 1, it was confirmed that Examples 1 and 2 of the present invention had significantly less chlorine content at the PPS ends than Comparative Examples 1 to 5.

Claims (10)

Sulfur containing an alkali metal hydrosulfide and an alkali metal hydroxide in a mixed solvent of water and an amide compound in the presence of an organic acid salt of an alkali metal, and a sulfide of the alkali metal and a mixed solvent of water and an amide compound A first step of preparing a source;
A second step of preparing a polyarylene sulfide by polymerization reaction by adding a dihalogenated aromatic compound and an amide compound to the reactor containing the sulfur source; And
Including the third step of removing the chlorine of the polyarylene sulfide end group by adding a phase separation agent including water and an additive for substituting the polyarylene sulfide end group to the reactor of the second step in which the polymerization reaction is completed. ,
The polyarylene sulfide end group substitution additive is a method for producing a polyarylene sulfide comprising at least one aromatic salt compound selected from compounds represented by the following formulas 1 and 2.
[Formula 1]
Ar ₁ -SM ₁
[Formula 2]
M ₂ COO-Ar ₂ -SH
(In the above formula, Ar ₁ is aryl having 6 to 60 carbon atoms, Ar ₂ is arylene having 6 to 60 carbon atoms, M ₁ And M ₂ are each independently an alkali metal)
According to claim 1,
In Chemical Formula 1, Ar ₁ is aryl having 6 to 10 carbon atoms, and M ₁ is Li or Na.
According to claim 1,
In Chemical Formula 2, Ar ₂ is an arylene having 6 to 10 carbon atoms, and M ₂ is Li or Na.
According to claim 1,
The phase-separating agent is a method for producing polyarylene sulfide containing an additive for sub-group substitution of 0.5 to 10 mol% of polyarylene sulfide.
According to claim 1,
The alkali metal hydroxide comprises lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, or cesium hydroxide, a method for producing polyarylene sulfide.
According to claim 1,
The alkali metal organic acid salt comprises lithium acetate, sodium acetate or a mixture thereof, a method for producing polyarylene sulfide.
According to claim 1,
The dihalogenated aromatic compound is o-dihalobenzene, m-dihalobenzene, p-dihalobenzene, dihalotoluene, dihalonaphthalene, dihalobiphenyl, dihalobenzoic acid, dihalodiphenyl ether, dihalodiphenylsulfone, A method for producing polyarylene sulfide comprising any one or two or more selected from the group consisting of dihalodiphenyl sulfoxide and dihalodiphenyl ketone.
According to claim 1,
The polyarylene sulfide is produced in a yield of 83% or more, and the polyarylene sulfide having a melt mass flow rate (MFR) of 200 to 1000 g / 10min measured under a 5 kg load condition according to the method of ASTM D 1238-10. Method of manufacturing.
The method of claim 8,
After the third step, further comprising the step of washing the reaction mixture with water and an organic solvent and drying, a method for producing polyarylene sulfide.
According to claim 1,
A method for producing polyarylene sulfide having a chlorine content of 1500 ppm or less measured by X-ray fluorescence (XRF) analysis.

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