KR20210111634A - Manufacturing method for polyarylene sulfide and polyarylene sulfide manufactured by the same - Google Patents

Abstract

The present invention relates to a method for preparing polyarylene sulfide and polyarylene sulfide prepared thereby. Specifically, the present invention relates to a method which can easily prepare high molecular weight polyarylene sulfide by controlling a process of adding water during polymerization, and polyarylene sulfide prepared thereby.

Description

Method for producing polyarylene sulfide and polyarylene sulfide prepared thereby

The present invention relates to a method for preparing polyarylene sulfide and to polyarylene sulfide prepared thereby.

Polyarylene sulfide (PAS) is a material that replaces metal, especially die casting metal such as aluminum or zinc, in automobiles, electric/electronic products, and machinery due to its excellent strength, heat resistance, flame retardancy and workability. It is widely used.

Among polyarylene sulfides, polyphenylene sulfide (PPS) is produced in a crosslinked form to increase molecular weight. However, the cross-linked PPS has a problem in that it is difficult to extrude, so there is a limitation in being applied to various fields. Accordingly, although the development of a linear PPS is in progress, in order to effectively increase the molecular weight of the linear PPS, expensive lithium is used during the manufacturing process.

Therefore, there is a need for a technology capable of easily producing polyarylene sulfide having a high molecular weight.

An object of the present invention is to provide a method for easily producing polyarylene sulfide having a high molecular weight and polyarylene sulfide prepared thereby.

However, the problems to be solved by the present invention are not limited to the above-mentioned problems, and other problems not mentioned will be clearly understood by those skilled in the art from the following description.

An exemplary embodiment of the present invention comprises the steps of reacting an alkali metal hydrosulfide with a hydroxide of an alkali metal in a mixed solvent containing water and an amide compound, followed by dehydration to obtain a sulfur source including an alkali metal sulfide; preparing a polyarylene sulfide prepolymer by adding a mixed solution containing an amide-based compound and a dihalogenated aryl-based compound to a reaction system including the sulfur source, followed by a primary polymerization reaction; and secondary polymerization of the polyarylene sulfide prepolymer, wherein water is added during the secondary polymerization, wherein the sulfur source is 1.2 moles or less of water based on 1 mole of sulfur atoms of the sulfide of the alkali metal. It provides a method for producing polyarylene sulfide comprising a.

In addition, another exemplary embodiment of the present invention provides polyarylene sulfide prepared by the method for preparing polyarylene sulfide and having a linear structure.

The method for producing polyarylene sulfide according to an exemplary embodiment of the present invention can easily produce polyarylene sulfide having a high molecular weight.

In addition, the method for producing polyarylene sulfide according to an exemplary embodiment of the present invention may produce polyarylene sulfide satisfying a melt flow rate within a specific range.

In addition, the polyarylene sulfide according to an exemplary embodiment of the present invention may have a high molecular weight linear structure.

Effects of the present invention are not limited to the above-described effects, and effects not mentioned will be clearly understood by those skilled in the art from the present specification and accompanying drawings.

In the present specification, when a part "includes" a certain component, this means that other components may be further included rather than excluding other components unless otherwise stated.

In this specification, when a member is said to be located "on" another member, this includes not only a case in which a member is in contact with another member but also a case in which another member exists between the two members.

In the present specification, the "weight average molecular weight" of a compound may be calculated using the molecular weight and molecular weight distribution of the compound. Specifically, as a method for measuring the weight average molecular weight of polyarylene sulfide, polyarylene sulfide is dissolved with α-chloronaphthalene at a temperature of 250 ° C., and measured over GPC (gel permeation chromatography: column temperature 210 ° C.) method was used.

An exemplary embodiment of the present invention comprises the steps of reacting an alkali metal hydrosulfide with a hydroxide of an alkali metal in a mixed solvent containing water and an amide compound, followed by dehydration to obtain a sulfur source including an alkali metal sulfide; preparing a polyarylene sulfide prepolymer by adding a mixed solution containing an amide-based compound and a dihalogenated aryl-based compound to a reaction system including the sulfur source, followed by a primary polymerization reaction; and secondary polymerization of the polyarylene sulfide prepolymer, wherein water is added during the secondary polymerization, wherein the sulfur source is 1.2 moles or less of water based on 1 mole of sulfur atoms of the sulfide of the alkali metal. It provides a method for producing polyarylene sulfide comprising a.

The method for producing polyarylene sulfide according to an exemplary embodiment of the present invention can easily produce polyarylene sulfide having a high molecular weight. In addition, the method for producing polyarylene sulfide according to an exemplary embodiment of the present invention may produce polyarylene sulfide satisfying a melt flow rate within a specific range.

According to an exemplary embodiment of the present invention, the reaction system (eg, inside the reactor) may be filled with the mixed solvent, the alkali metal hydrosulfide and the alkali metal hydroxide.

According to an exemplary embodiment of the present invention, a hydrosulfide of an alkali metal may be used to prepare polyarylene sulfide. The alkali metal hydrosulfide may be lithium hydrosulfide, sodium hydrosulfide, potassium hydrosulfide, rubidium hydrosulfide, cesium hydrosulfide, and mixtures of two or more thereof.

According to an exemplary embodiment of the present invention, a sulfide of an alkali metal may be formed by reacting a hydrosulfide of an alkali metal with a hydroxide of an alkali metal. At this time, with respect to 1 equivalent of the alkali metal hydrosulfide, 0.9 equivalent or more and 2.0 equivalent or less of the alkali metal hydroxide may be added to the reaction system. Specifically, the content of the hydroxide of the alkali metal may be 1.0 equivalent or more and 1.5 equivalents or less, or 1.0 equivalent or more and 1.1 equivalents or less with respect to 1 equivalent of the alkali metal hydrosulfide. By adjusting the relative content between the hydrosulfide of the alkali metal and the hydroxide of the alkali metal in the above-described range, the sulfide of the alkali metal may be stably formed.

According to an exemplary embodiment of the present invention, the reaction of the alkali metal hydrosulfide and the alkali metal hydroxide may be performed in a mixed solvent including water and an amide-based compound.

According to an exemplary embodiment of the present invention, the amide compound included in the mixed solvent may include an amide compound such as N,N-dimethylformamide or N,N-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 a phosphoric acid amide compound such as hexamethylphosphoric acid triamide, and the like, and any one or a mixture of two or more thereof may be used. Among them, the amide-based compound may be more specifically N-methyl-2-pyrrolidone (NMP) in consideration of the reaction efficiency and the cosolvent effect as a polymerization solvent during polymerization for preparing polyarylene sulfide. In addition, the water included in the mixed solvent may be deionized water (D.I.).

According to an exemplary embodiment of the present invention, the content of water included in the mixed solvent may be 1 equivalent or more and 8 equivalents or less with respect to 1 equivalent of the amide-based compound. Specifically, with respect to 1 equivalent of the amide compound, 1.5 equivalents or more and 5 equivalents or less, or 2.5 equivalents or more and 4.5 equivalents or less may be mixed. By adjusting the content of water and the amide-based compound included in the mixed solvent to the above-described range, it is possible to stably form a sulfide of an alkali metal.

According to an exemplary embodiment of the present invention, the mixed solvent may further include at least one organic acid metal salt of sodium acetate, magnesium acetate, lithium acetate, sodium hexanoate, lithium hexanoate, sodium benzoate and lithium benzoate. can By adding the organic acid metal salt to the mixed solvent, the efficiency of a polymerization reaction to be described later may be improved.

The organic acid metal salt may be added in an amount of 0.3 to 0.6 equivalents based on 1 equivalent of the aqueous sulfide of the alkali metal. Specifically, the content of the organic acid metal salt may be 0.35 equivalent or more and 0.55 equivalent or less, or 0.4 equivalent or more and 0.5 equivalent or less, based on 1 equivalent of the alkali metal hydrosulfide. By adjusting the content of the organic acid metal salt to the above-described range, the efficiency of the polymerization reaction can be further improved.

According to an exemplary embodiment of the present invention, as a result of the reaction of the alkali metal hydrosulfide and the alkali metal hydroxide as described above, the alkali metal sulfide may be precipitated as a solid in a mixed solvent of water and an amide compound.

According to an exemplary embodiment of the present invention, dehydration may be performed to remove water or the like from the reaction product including the sulfide of the alkali metal to some extent. Through this, a sulfur source including alkali metal sulfide and water may be prepared, and the sulfur source may be formed in the form of a solution containing metal sulfide and water.

According to an exemplary embodiment of the present invention, the dehydration step may prepare a sulfur source containing 1.2 moles or less of water with respect to 1 mole of sulfur atoms of the sulfide of the alkali metal. Specifically, the content of water contained in the sulfur source formed in the dehydration step is 1.0 mol or more and 1.2 mol or less, 1.0 mol or more and 1.17 mol or less, or 1.0 mol or more and 1.15 mol or less with respect to 1 mol of the sulfur atom of the sulfide of the alkali metal. can

By performing dehydration so that the content of water contained in the sulfur source falls within the above-described range, the molecular weight of the polyarylene sulfide to be polymerized can be effectively increased. Specifically, by reducing the content of water contained in the sulfur source before the polymerization reaction to the above range and adding water in the secondary polymerization step to be described later, the molecular weight of the polyarylene sulfide to be prepared can be effectively increased.

According to an exemplary embodiment of the present invention, the dehydration may be performed at a temperature of 180 ℃ or more and 200 ℃ or less. When the temperature at which the dehydration proceeds is within the above range, while removing an appropriate amount of water, the removal of sulfides and amide compounds of alkali metals used in the polymerization reaction may be minimized.

According to an exemplary embodiment of the present invention, in the method for producing polyarylene sulfide, before the step of preparing the polyarylene sulfide prepolymer, the temperature of the reaction system including the sulfur source is adjusted to a temperature of 150 ℃ or more and 180 ℃ or less. It may further include the step of adjusting. By adjusting the temperature of the reaction system to the above-mentioned range before the step of preparing the polyarylene sulfide prepolymer, the stability of the primary polymerization reaction can be improved.

According to an exemplary embodiment of the present invention, a mixed solution including an amide-based compound and a dihalogenated aryl-based compound may be added to the reaction system including the sulfur source. Thereafter, a primary polymer may be formed by polymerizing the sulfide of an alkali metal contained in the sulfur source and the dihalogenated aryl compound contained in the mixed solution. Specifically, the primary polymer may include a polyarylene sulfide prepolymer.

According to an exemplary embodiment of the present invention, the dihalogenated aryl compound may be a compound in which two hydrogens in an aromatic ring are substituted with halogen atoms. Specifically, the dihalogenated aryl compound is o-dihalobenzene, m-dihalobenzene, p-dihalobenzene, dihalotoluene, dihalonaphthalene, dihalobiphenyl, dihalobenzoic acid, dihalodiphenyl ether, dihal and rhodiphenylsulfone, dihalodiphenylsulfoxide, or dihalodiphenyl ketone, and any one or a mixture of two or more thereof may be used. In the dihalogenated aryl-based compound, the halogen atom may be fluorine, chlorine, bromine or iodine. Among them, p-dichlorobenzene (p-DCB) may be used in consideration of the effect of reducing reactivity and side reaction generation during the preparation of polyarylene sulfide.

According to an exemplary embodiment of the present invention, the dihalogenated aryl-based compound may be added in an amount of 0.8 equivalent or more and 1.2 equivalent or less, or 0.8 equivalent or more and 1.1 equivalent or less based on 1 equivalent of the hydrosulfide of the alkali metal. When the dihalogenated aryl-based compound is added within the above-described content range, the yield of finally prepared polyarylene sulfide may be improved.

According to an exemplary embodiment of the present invention, the amide compound included in the mixed solution may include an amide compound such as N,N-dimethylformamide or N,N-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 a phosphoric acid amide compound such as hexamethylphosphoric acid triamide, and the like, and any one or a mixture of two or more thereof may be used. In particular, the same compound as the amide compound used in the mixed solvent may be used in the preparation of the mixed solution. Specifically, N-methyl-2-pyrrolidone (NMP) may be used as the amide compound used in the mixed solvent and the mixed solution.

According to an exemplary embodiment of the present invention, in the step of preparing the polyarylene sulfide prepolymer, the mixed solution may be added so that the content of the amide compound is 3.1 moles or more with respect to 1 mole of the sulfur atom in the reaction system. Specifically, the mixed solution is added to the reaction system so that the content of the amide compound is 3.1 mol or more and 3.2 mol or less, 3.11 mol or more and 3.18 mol or less, or 3.12 mol or more and 3.15 mol or less with respect to 1 mol of the sulfur atom contained in the reaction system. can be added. When the content of the sulfur atom and the amide-based compound in the reaction system to which the mixed solution is added is within the aforementioned range, polyarylene sulfide having excellent physical properties can be prepared without fear of lowering the melt viscosity of the produced polyarylene sulfide. can

According to an exemplary embodiment of the present invention, the step of preparing the polyarylene sulfide prepolymer may be performed at a temperature of 225°C or higher and 245°C or lower. By controlling the temperature of the step of preparing the polyarylene sulfide prepolymer (eg, primary polymerization) to the above-mentioned range, the primary polymer including the polyarylene sulfide prepolymer may be stably formed. In addition, the step of preparing the polyarylene sulfide prepolymer may be performed for 2 to 4 hours.

According to an exemplary embodiment of the present invention, polyarylene sulfide may be formed by secondary polymerization of polyarylene sulfide prepolymer. Specifically, polyarylene sulfide having a high molecular weight may be formed through secondary polymerization in which the chains of polyarylene sulfide prepolymers formed by primary polymerization are extended. In this case, the high molecular weight polyarylene sulfide may have a linear structure.

The secondary polymerization may proceed continuously with respect to the primary polymerization, and the temperature at which the secondary polymerization is performed may be higher than the temperature at which the primary polymerization is performed. Specifically, the step of preparing the secondary polymer may be performed at a temperature of 250 °C or higher and 270 °C or lower. When the temperature of the step of preparing the secondary polymer is within the above-mentioned range, the chains of the polyarylene sulfide prepolymers are effectively extended, so that polyarylene sulfide having a high molecular weight can be stably prepared. In addition, the step of preparing the secondary polymer may be performed for 1 hour to 2 hours.

According to an exemplary embodiment of the present invention, water may be added during the secondary polymerization of the polyarylene sulfide prepolymer. By adding water in the process of secondary polymerization, salts, which are reaction by-products, are effectively removed from the dilute phase of the polyarylene sulfide formed, thereby effectively increasing the molecular weight of the polyarylene sulfide finally produced. can

According to an exemplary embodiment of the present invention, in the step of adding water during the secondary polymerization, when the total time for the secondary polymerization is 100%, water is added at a time point of 40% or more and 70% or less. can Specifically, when the total time for secondary polymerization is 100%, 45% or more and 65% or less, 50% or more and 60% or less, 40% or more and 55% or less, or 50% or more 60 Water can be added at up to % time points. For example, when the completion of the secondary polymerization is set to 1 hour, water may be added at a time point of not less than 24 minutes and not more than 42 minutes after starting the secondary polymerization.

The time at which the secondary polymerization is completed may be set using a database formed based on the results of polymerization under the same conditions as the secondary polymerization according to an exemplary embodiment of the present invention.

By controlling the time point at which water is added during the secondary polymerization process as described above, it is possible to effectively remove by-products from the dilute phase of polyarylene sulfide formed while stably proceeding the secondary polymerization. In addition, phase separation of the prepared high molecular weight polyarylene sulfide from the reactant can be effectively induced.

According to an exemplary embodiment of the present invention, in the step of adding water during the secondary polymerization, water may be added so that the content of water is 1.6 mol or more with respect to 1 mol of the sulfur atom in the reaction system. Specifically, as water is added to the reaction system in which the secondary polymerization is performed, the content of water with respect to 1 mole of sulfur atoms contained in the reaction system is 1.6 mol or more and 2.1 mol or less, 1.65 mol or more and 2.05 mol or less, 1.8 mol or more and 1.95 mol or more moles or less, 1.65 moles or more and 1.95 moles or less, 1.8 moles or more and 2.1 moles or less, or 1.95 moles or more and 2.05 moles or less. By controlling the content of water added in the process of secondary polymerization to the above-mentioned range, the reaction salts are removed from the polyarylene sulfide formed, thereby effectively increasing the molecular weight of the polyarylene sulfide to be prepared.

According to an exemplary embodiment of the present invention, in the step of adding water during the secondary polymerization, the difference in the content of water with respect to 1 mol of the sulfur atom before and after adding water in the reaction system may be 0.5 mol or more. Specifically, based on 1 mole of sulfur atoms contained in the reaction system, the content of water in the reaction system to which water is added during the secondary polymerization (eg, the second content) is higher than the content of water in the reaction system before water is added (eg, the first content). 0.5 mol or more and 1.0 mol or less may be large. More specifically, the difference between the second content and the first content is 0.5 mol or more and 0.9 mol or less, 0.6 mol or more and 0.9 mol or less, 0.7 mol or more and 0.9 mol or less, 0.8 mol or more and 0.9 mol or less, 0.5 mol or more and 0.8 mol or less, or It may be 0.5 mol or more and 0.65 mol or less.

In the step of preparing the secondary polymer, when the difference in the content of water with respect to 1 mole of sulfur atoms included in the reaction system before and after water is added is within the above range, from the lean phase of the polyarylene sulfide formed Salts, which are reaction by-products, can be effectively removed. Through this, polyarylene sulfide having high purity and high molecular weight can be easily prepared.

According to an exemplary embodiment of the present invention, the method for producing polyarylene sulfide may further include washing the obtained polyarylene sulfide at least once after obtaining the polyarylene sulfide. have. The obtained polyarylene sulfide may be in the form of a slurry containing impurities. The obtained polyarylene sulfide slurry can be washed three times, or four or more times. More specifically, the obtained polyarylene sulfide slurry may be washed 5 times or more.

The polyarylene sulfide may be washed using washing water. By washing the obtained polyarylene sulfide with washing water, sodium chloride (NaCl) and a base component, which are by-products generated during polymerization of polyarylene sulfide, can be removed.

According to an exemplary embodiment of the present invention, water containing an amide-based compound or an organic acid may be used as the washing water. In this case, deionized water may be used as the water. In addition, when washing is performed a plurality of times, for each washing, an amide-based compound may be used as a washing water or water containing an organic acid may be used as a washing water. For example, the first and second washes may be performed with an amide compound, and the third to fifth washes may be performed using water containing an organic acid.

The amide compound used in the washing water is not particularly limited, but may include amide compounds such as N-dimethylformamide or N,N-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 a phosphoric acid amide compound such as hexamethylphosphoric acid triamide, and the like, and any one or a mixture of two or more thereof may be used. More specifically, N-methyl-2-pyrrolidone (NMP) may be used as washing water. By using the same as the amide compound used in the above-described mixed solvent and mixed solution as washing water, by-products can be more effectively removed.

Alternatively, water containing an organic acid may be used as the washing water. In this case, the concentration of the organic acid contained in the water may be 0.1 wt% or more and 0.5 wt% or less. By using water containing the organic acid of the above concentration as washing water, by-products generated during polymerization can be easily removed. In this case, the type of organic acid dissolved in the water of the washing water is not limited, but acetic acid may be used in the present invention.

According to an exemplary embodiment of the present invention, the washing may be performed at a temperature of 80 ℃ or more and 100 ℃ or less. Specifically, when the washing is performed a plurality of times, each washing may be performed at a temperature of 80 °C or more and 100 °C or less, or 90 °C or more and 95 °C or less. When the washing water temperature is within the above-mentioned range, the solubility of by-products generated during the preparation of polyarylene sulfide in washing water is increased, and by-products such as sodium chloride can be removed as much as possible.

When the washing is performed multiple times, the polyarylene sulfide that has been washed may be filtered through a filter, and then the next washing may be performed. That is, the filtration step may be performed between a plurality of washing steps.

According to an exemplary embodiment of the present invention, the method for producing polyarylene sulfide may include drying the polyarylene sulfide that has been washed. Specifically, the washed polyarylene sulfide may be dried by at least one of hot air drying and vacuum drying. The hot air drying may be performed at a temperature of 80 °C to 120 °C, and the vacuum drying may be performed at a temperature of 120 °C to 170 °C. Specifically, after the washing step, hot air drying may be performed at a temperature of 80 °C to 120 °C, and then vacuum drying may be performed at a temperature of 120 °C to 170 °C.

By drying the polyarylene sulfide washed as described above, the mechanical properties of the polyarylene sulfide can be improved, and impurities can be effectively removed from the polyarylene sulfide.

Another exemplary embodiment of the present invention provides polyarylene sulfide prepared by the method for preparing polyarylene sulfide and having a linear structure.

The polyarylene sulfide according to an exemplary embodiment of the present invention may have a high molecular weight linear structure.

According to an exemplary embodiment of the present invention, the polyarylene sulfide has a non-cross-linked, linear structure, and thus extrusion molding is easy, so that it can be easily applied to various fields. In addition, the polyarylene sulfide has a linear structure and at the same time has a high molecular weight, thereby implementing excellent physical properties.

According to an exemplary embodiment of the present invention, the melt flow rate of the polyarylene sulfide may be 100 g/10min or more and 200 g/10min or less. Specifically, the melt flow rate of the finally prepared polyarylene sulfide is 130 g/10min or more and 195 g/10min or less, 140 g/10min or more and 190 g/10min or less, 150 g/10min or more and 180 g or more. /10min or less, 140 g/10min or more and 165 g/10min or less, or 175 g/10min or more and 190 g/10min or less. Polyarylene sulfide satisfying the melt flow rate in the above range may have a high viscosity and may have excellent physical properties.

The melt flow rate of the polyarylene sulfide may be measured according to ASTM-D1238-70. Specifically, in accordance with ASTM-D1238-70, the melt flow rate of polyarylene sulfide may be measured at 315° C., 4 minutes, and under a load of 5 kg.

According to an exemplary embodiment of the present invention, the weight average molecular weight of the polyarylene sulfide may be 40,000 g/mol or more and 50,000 g/mol or less. Specifically, the weight average molecular weight of the finally prepared polyarylene sulfide is 42,000 g/mol or more and 49,000 g/mol or less, 44,000 g/mol or more and 48,500 g/mol or less, 40,000 g/mol or more and 46,000 g/mol or less, or It may be 45,000 g/mol or more and 50,000 g/mol or less. Polyarylene sulfide having a weight average molecular weight in the above-described range may have excellent physical properties.

As described above, the polyarylene sulfide prepared by the above manufacturing method has the above-described melt flow rate and weight average molecular weight, so that it can be used in the production of molded articles for replacing metals in automobiles, electric and electronic products or mechanical parts, particularly excellent mechanical properties. It may be useful for manufacturing a reflector for an automobile lamp, a base plate, and the like, which require properties.

Hereinafter, examples will be given to describe the present invention in detail. However, the embodiments according to the present invention may be modified in various other forms, and the scope of the present invention is not to be construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more completely explain the present invention to those of ordinary skill in the art.

Example 1

Sulfur Source Manufacturing

Into the reactor 1 equivalent of sodium hydrogen sulfide (NaSH), 1.05 equivalent of sodium hydroxide (NaOH), 4.72 equivalent of deionized water (DI water), 1.65 equivalent of N-methyl-2-pyrrolone (NMP) and 0.44 equivalent of acetic acid Sodium (NaOAc) was added, and the reactor was connected.

Thereafter, the inside of the reactor was made into a nitrogen atmosphere, and then the dehydration valve was slowly opened and the temperature was raised so that there was a constant flow of nitrogen, and the sulfur source generated inside the reactor was liquefied through a condenser, and then collected. At this time, the temperature rise condition was heated at 140 ℃ 80 minutes while dehydration proceeded to obtain a sulfur source. Then, when the reactor reached 185° C., the dehydration valve was closed.

The content of water with respect to 1 mole of sulfur atoms of the sulfur source as measured by the Karl Fischer method was 1.15 moles.

primary polymerization

Then, when the temperature of the reactor reaches 180 ° C., 1.05 equivalents of p-dichlorobenzene (p-DCB), and NMP in an amount of 3.12 moles per mole of sulfur atoms in the reactor are added to the reactor containing the sulfur source. Then, the temperature was raised to about 230 °C and the temperature was maintained for 3 hours, and the primary polymerization was performed to prepare a primary polymer.

secondary polymerization

Thereafter, when the temperature of the reactor is raised to about 255 ° C. and 30 minutes have elapsed, water is added so that the content of water per mole of sulfur atoms in the reactor is 1.65 moles, and secondary polymerization is further performed for 30 minutes to form a phase-separated secondary polymer. A slurry comprising polyphenylene sulfide (PPS) was obtained.

washing and drying

The obtained PPS slurry was washed with NMP at a temperature of about 90° C. and then filtered through a 75 μm mesh twice. Thereafter, the filtered PPS slurry was washed with water containing 0.2% by weight of acetic acid at a temperature of about 90° C. and then filtered through a 75 μm mesh three times.

Thereafter, the washed PPS was dried in a vacuum oven at 150° C. for 7 hours to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Example 2

In the same manner as in Example 1, a sulfur source and a primary polymer having a water content of 1.15 moles per 1 mole of sulfur atoms were prepared.

Thereafter, in the process of preparing the secondary polymer, the reactor was heated to about 255° C. and 30 minutes passed, except that water was added so that the content of water per mole of sulfur atoms in the reactor was 1.80 moles in the same manner as in Example 1 A slurry containing polyphenylene sulfide (PPS) as a secondary polymer was obtained.

Thereafter, the PPS slurry obtained in the same manner as in Example 1 was washed and dried to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Example 3

In the same manner as in Example 1, a sulfur source and a primary polymer having a water content of 1.15 moles per 1 mole of sulfur atoms were prepared.

Thereafter, in the process of preparing the secondary polymer, the reactor was heated to about 255° C. and 30 minutes later, water was added so that the content of water per mole of sulfur atoms in the reactor was 1.95 moles in the same manner as in Example 1 A slurry containing polyphenylene sulfide (PPS) as a secondary polymer was obtained.

Thereafter, the PPS slurry obtained in the same manner as in Example 1 was washed and dried to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Example 4

In the same manner as in Example 1, a sulfur source and a primary polymer having a water content of 1.15 moles per 1 mole of sulfur atoms were prepared.

Thereafter, in the process of preparing the secondary polymer, the reactor was heated to about 255° C. and 30 minutes later, water was added so that the content of water per mole of sulfur atoms in the reactor was 1.95 moles in the same manner as in Example 1 A slurry containing polyphenylene sulfide (PPS) as a secondary polymer was obtained.

Thereafter, the obtained PPS slurry was washed with NMP at a temperature of about 90° C. and filtered through a 75 μm mesh. Thereafter, the filtered PPS slurry was washed with water containing 0.2% by weight of acetic acid at a temperature of about 90° C. and then filtered through a 75 μm mesh. Thereafter, the filtered PPS slurry was washed with NMP at a temperature of about 90° C. and then filtered through a 75 μm mesh. Thereafter, the filtered PPS slurry was washed with water containing 0.2% by weight of acetic acid at a temperature of about 90° C. and then filtered through a 75 μm mesh twice.

Thereafter, the washed PPS was dried in the same manner as in Example 1 to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Example 5

In the same manner as in Example 1, a sulfur source and a primary polymer having a water content of 1.15 moles per 1 mole of sulfur atoms were prepared.

Thereafter, in the process of preparing the secondary polymer, the temperature of the reactor was raised to about 255° C., and when 30 minutes had elapsed, water was added so that the content of water per mole of sulfur atoms in the reactor was 2.05 moles in the same manner as in Example 1 A slurry containing polyphenylene sulfide (PPS) as a secondary polymer was obtained.

Thereafter, the PPS slurry obtained in the same manner as in Example 4 was washed and dried to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Comparative Example 1

A sulfur source was prepared in the same manner as in Example 1, except that a sulfur source having a water content of 1.65 moles relative to 1 mole of sulfur atoms was prepared by controlling the dehydration conditions in Example 1.

Thereafter, in the process of preparing the primary polymer, a primary polymer was prepared in the same manner as in Example 1, except that NMP was added in an amount of 3.00 mol per 1 mol of sulfur atoms in the reactor.

Thereafter, in the process of preparing the secondary polymer, secondary polymerization was performed at a temperature of about 255 ° C. for 1 hour without additional water added, thereby obtaining a slurry containing polyphenylene sulfide (PPS), which is a secondary polymer. did.

Thereafter, the PS slurry obtained was washed with NMP at a temperature of about 90° C. and filtered through a 75 μm mesh. Thereafter, the filtered PPS slurry was washed with water containing 0.2% by weight of acetic acid at a temperature of about 90° C. and then filtered through a 75 μm mesh three times.

Thereafter, the washed PPS was dried in the same manner as in Example 1 to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Comparative Example 2

In the same manner as in Example 1, a sulfur source having a water content of 1.15 moles per mole of sulfur atoms was prepared.

Thereafter, in the process of preparing the primary polymer, a primary polymer was prepared in the same manner as in Example 1, except that NMP was added in an amount of 3.00 mol per 1 mol of sulfur atoms in the reactor.

Thereafter, immediately after the temperature of the reactor is raised to about 255° C. in the process of preparing the secondary polymer (at the start of the secondary polymerization), water is added so that the content of water per mol of sulfur atoms in the reactor becomes 1.65 mol, and the second time for 1 hour Polymerization was performed to obtain a slurry containing polyphenylene sulfide (PPS) as a secondary polymer.

Thereafter, the PPS slurry obtained in the same manner as in Example 1 was washed and dried to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Comparative Example 3

In the same manner as in Comparative Example 1, a sulfur source having a water content of 1.65 moles per mole of sulfur atoms was prepared.

Thereafter, in the process of preparing the primary polymer, a primary polymer was prepared in the same manner as in Example 1, except that NMP was added in an amount of 3.12 mol per 1 mol of sulfur atoms in the reactor.

Thereafter, in the process of preparing the secondary polymer in the same manner as in Comparative Example 1, secondary polymerization was performed without additionally adding water, thereby obtaining a slurry containing polyphenylene sulfide (PPS) as the secondary polymer.

Thereafter, the PPS slurry obtained in the same manner as in Example 1 was washed and dried to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Comparative Example 4

A sulfur source was prepared in the same manner as in Example 1, except that a sulfur source having a water content of 1.8 moles relative to 1 mole of sulfur atoms was prepared by controlling the dehydration conditions in Example 1.

Thereafter, in the process of preparing the primary polymer, a primary polymer was prepared in the same manner as in Example 1, except that NMP was added in an amount of 3.12 mol per 1 mol of sulfur atoms in the reactor.

Thereafter, in the process of preparing the secondary polymer in the same manner as in Comparative Example 1, secondary polymerization was performed without additionally adding water, thereby obtaining a slurry containing polyphenylene sulfide (PPS) as the secondary polymer.

Thereafter, the PPS slurry obtained in the same manner as in Example 1 was washed and dried to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Comparative Example 5

A sulfur source was prepared in the same manner as in Example 1, except that the dehydration conditions were adjusted in Example 1 to prepare a sulfur source having a water content of 1.12 moles per 1 mole of sulfur atoms.

Thereafter, in the process of preparing the primary polymer, a primary polymer was prepared in the same manner as in Example 1, except that NMP was added in an amount of 3.12 mol per 1 mol of sulfur atoms in the reactor.

Thereafter, immediately after the temperature of the reactor is raised to about 255° C. in the process of preparing the secondary polymer (the start of secondary polymerization), water is added so that the content of water per 1 mol of sulfur atoms in the reactor becomes 1.65 mol, and the second time for 1 hour Polymerization was performed to obtain a slurry containing polyphenylene sulfide (PPS) as a secondary polymer.

Thereafter, the PPS slurry obtained in the same manner as in Example 1 was washed and dried to finally prepare polyphenylene sulfide, which is polyarylene sulfide.

Process conditions for preparing polyarylene sulfide in Examples 1 to 5 and Comparative Examples 1 to 5 are shown in Table 1 below.

In Table 1 below, “(A) NMP/S” refers to the content (mol) of NMP per 1 mole of sulfur atoms in the reactor in the process of preparing the primary polymer, and “(B)” refers to the preparation of the secondary polymer refers to the period of adding water in the process, and “(C) H ₂ O/S” refers to the content (mol) of water per mole of sulfur atoms in the reactor in the process of preparing the secondary polymer.

division (A) NMP/S (B) Timing of addition (C) H ₂ O/S (C1) before addition (C2) after addition Example 1 3.12 30 minutes 1.15 1.65 Example 2 3.12 30 minutes 1.15 1.80 Example 3 3.12 30 minutes 1.15 1.95 Example 4 3.12 30 minutes 1.15 1.95 Example 5 3.12 30 minutes 1.15 2.05 Comparative Example 1 3.00 input X 1.65 1.65 Comparative Example 2 3.00 0 minutes 1.15 1.65 Comparative Example 3 3.12 input X 1.65 1.65 Comparative Example 4 3.12 input X 1.8 1.8 Comparative Example 5 3.12 0 minutes 1.12 1.65

Experimental Example 1 (Measurement of melt flow rate)

Melt flow rate (MFR) of the polyphenylene sulfide prepared in Examples 1 to 5 and Comparative Examples 1 to 5 according to the method of ASTM D1238-70 was measured.

Specifically, the melt flow rate was determined by using a Gottfert MI-4 apparatus at a temperature of 315° C. and a load of 5 kg. Polyphenylene sulfide prepared in Examples 1 to 5 and Comparative Examples 1 to 5 was placed on each and the molten material was measured by weighing the timed segments of the extrudate and calculating the extrusion rate in g/10min. At this time, the inner diameter of the standard die was 2.1 mm and the length was 8 mm.

Table 2 below shows the measured values corresponding to 4 minutes in the division by time.

division transference number(%) MFR
(g/10min) Example 1 87.0 187 Example 2 86.2 147 Example 3 89.4 190 Example 4 85.9 161 Example 5 89.4 177 Comparative Example 1 85.0 667 Comparative Example 2 87.0 307 Comparative Example 3 87.2 520 Comparative Example 4 86.1 424 Comparative Example 5 85.7 309

Experimental Example 2 (weight average molecular weight measurement)

The weight average molecular weights of the polyphenylene sulfide prepared in Examples 1 to 3 and Comparative Examples 1 to 2 were measured and shown in Table 3 below.

division weight average molecular weight
(Mw, g/mol) Example 1 44,021 Example 2 48,213 Example 3 45,558 Comparative Example 1 31,069 Comparative Example 2 32,875

Referring to Tables 1 and 2, it was confirmed that the polyarylene sulfide prepared according to Examples 1 to 5, in which water was added during the secondary polymerization process, had a melt flow index of 200 g/10min or less. . In addition, Examples 1 to 5 confirmed that the yield of polyarylene sulfide was high.

In particular, by preparing a sulfur source containing 1.2 mol or less of water with respect to 1 mol of sulfur atom, and adding water during secondary polymerization, the melt flow index of the prepared polyarylene sulfide is 200 g/10min or less It was confirmed that it can be controlled by

Furthermore, the content of water with respect to 1 mol of sulfur atoms included in the reactor before and after addition of water in the secondary polymerization is adjusted so that there is a difference of 0.5 mol or more, and the water content is 1.6 mol or more with respect to 1 mol of sulfur atoms It was confirmed that in Examples 1 to 5 in which water was added to the reactor so that the melt flow index of polyarylene sulfide could be easily adjusted to 200 g/10min or less.

Meanwhile, referring to Examples 3 and 4, even when the conditions for preparing the sulfur source, the primary polymer, and the secondary polymer are the same, the yield of polyphenylene sulfide prepared according to the method of washing the obtained PPS slurry And it was confirmed that the melt flow rate can be adjusted.

On the other hand, it was confirmed that the melt flow rate of the polyarylene sulfides according to Comparative Examples 1, 3, and 4 to which water was not added during the secondary polymerization process exceeded 400 g/10min. Furthermore, it was confirmed that the melt flow rate of the polyarylene sulfides according to Comparative Examples 2 and 5, in which water was added immediately at the time the secondary polymerization was started, exceeded 300 g/10 min.

In addition, referring to Tables 1 and 3, it was confirmed that Examples 1 to 3 can adjust the weight average molecular weight of polyarylene sulfide to 40,000 g/mol or more and 50,000 g/mol or less. On the other hand, it was confirmed that the weight average molecular weight of the polyarylene sulfide prepared in Comparative Examples 1 and 2 was less than 40,000 g/mol. That is, it can be seen that polyarylene sulfide having excellent physical properties can be easily prepared through the method for preparing polyarylene sulfide according to an exemplary embodiment of the present invention.

Therefore, it can be seen that in the method for preparing polyarylene sulfide according to an exemplary embodiment of the present invention, polyarylene sulfide having a high molecular weight can be easily prepared by controlling the process of adding water during polymerization.

Claims (13)

a step of reacting an alkali metal hydrosulfide with an alkali metal hydroxide in a mixed solvent containing water and an amide compound, followed by dehydration to obtain a sulfur source containing an alkali metal sulfide;
preparing a polyarylene sulfide prepolymer by adding a mixed solution containing an amide-based compound and a dihalogenated aryl-based compound to a reaction system including the sulfur source, followed by a primary polymerization reaction; and
Secondary polymerization of the polyarylene sulfide prepolymer, comprising adding water during the secondary polymerization,
The method for producing polyarylene sulfide, wherein the sulfur source contains 1.2 moles or less of water based on 1 mole of sulfur atoms of the sulfide of the alkali metal.
The method according to claim 1,
The mixed solvent is
The method for producing polyarylene sulfide further comprising at least one organic acid metal salt of sodium acetate, magnesium acetate, lithium acetate, sodium hexanoate, lithium hexanoate, sodium benzoate and lithium benzoate.
The method according to claim 1,
The method for producing polyarylene sulfide wherein the dehydration is carried out at a temperature of 180 ℃ or more and 200 ℃ or less.
The method according to claim 1,
Before the step of preparing the polyarylene sulfide prepolymer,
The method for producing polyarylene sulfide further comprising the step of adjusting the temperature of the reaction system to a temperature of 150 °C or more and 180 °C or less.
The method according to claim 1,
The mixed solution is
The method for producing polyarylene sulfide is added so that the content of the amide-based compound is 3.1 moles or more with respect to 1 mole of the sulfur atom in the reaction system.
The method according to claim 1,
The step of adding water during the secondary polymerization is,
When the total time for the secondary polymerization is 100%, water is added at a time of 40% or more and 70% or less.
The method according to claim 1,
The step of adding water during the secondary polymerization is,
A method for producing polyarylene sulfide, wherein water is added so that the content of water is 1.6 mol or more with respect to 1 mol of the sulfur atom in the reaction system.
The method according to claim 1,
The step of adding water during the secondary polymerization is,
The method for producing polyarylene sulfide so that the difference in the content of water with respect to 1 mol of the sulfur atom before and after adding water in the reaction system is 0.5 mol or more.
The method according to claim 1,
After the second polymerization step,
A method for producing polyarylene sulfide, further comprising the step of washing the obtained polyarylene sulfide at least once.
10. The method of claim 9,
The washing is a method for producing polyarylene sulfide is performed at a temperature of 80 ℃ or more and 100 ℃ or less.
It is prepared by the method for producing polyarylene sulfide according to claim 1,
Polyarylene sulfide having a linear structure.
12. The method of claim 11,
The polyarylene sulfide has a melt flow rate of 100 g/10min or more and 200 g/10min or less of the polyarylene sulfide.
12. The method of claim 11,
The polyarylene sulfide has a weight average molecular weight of 40,000 g/mol or more and 50,000 g/mol or less of the polyarylene sulfide.