KR20160086002A

KR20160086002A - Method for preparing polyamide resin

Info

Publication number: KR20160086002A
Application number: KR1020150002952A
Authority: KR
Inventors: 권일경; 권소영; 김진규; 이기연; 전석민; 진영섭
Original assignee: 삼성에스디아이 주식회사
Priority date: 2015-01-08
Filing date: 2015-01-08
Publication date: 2016-07-19

Abstract

The method for producing a polyamide resin of the present invention comprises stirring and filtering a polyamide resin prepolymer in a non-solvent containing at least one of ethanol, ethyl acetate, and dichloropentafluoropropane; And solid-phase-polymerizing the filtered prepolymer. The above production method can economically improve the color and thermal characteristics of the polyamide resin by removing unreacted raw materials, reaction by-products and the like from the pre-solid state polymerization polyamide resin prepolymer.

Description

METHOD FOR PREPARING POLYAMIDE RESIN [0002]

The present invention relates to a process for producing a polyamide resin. More specifically, the present invention relates to a process for producing a polyamide resin which can economically improve the color and thermal properties of a polyamide resin.

Polyamide resins and the like are generally produced by a polycondensation reaction. As a polymerization method for carrying out such a polycondensation reaction, a melt polymerization method is generally used, but the melt polymerization method has a limitation in obtaining a high molecular weight polymer having a weight average molecular weight of 30,000 g / mol or more due to problems such as depolymerization and process transfer. Therefore, in order to further increase the molecular weight, intrinsic viscosity (IV) and the like of the prepared polymer, it is preferable to heat the low-molecular-weight polymer (lower condensate, prepolymer) in a solid state at a temperature lower than the melting temperature Solid state polymerization (SSP) may be performed. The solid phase polymerization process is performed at a lower temperature than the melt polymerization method and is free from environmental pollution due to the use of volatile organic solvents since no organic solvent is used.

However, since the solid phase polymerization method is a polymerization method in a solid state, there is a disadvantage that it is very difficult to remove unreacted raw materials and reaction by-products remaining in the prepolymer before solid phase polymerization from the inside of the prepolymer particles in a solid state. These unreacted raw materials, reaction by-products, and the like may discolor the final polymer product or form an oxidation product to lower the thermal properties such as the melting temperature. In order to prevent this, it is possible to use a method of dissolving the prepolymer to remove unreacted materials, impurities, and the like and recrystallization. However, this method is not economical because the depreciation cost increases as the amount of solvent used increases to improve the yield.

Therefore, it is necessary to develop a production method that can economically remove unreacted raw materials, reaction by-products and the like from the prepolymer and improve the color and thermal characteristics of the final polymer product.

Korean Patent Publication No. 10-2004-0016514

An object of the present invention is to provide a process for producing a polyamide resin which can economically remove an unreacted starting material, reaction by-products and the like from a polyamide prepolymer before polymerization in solid phase to improve the color and thermal properties of the polyamide resin .

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the present invention relates to a method for producing a polyamide resin. The preparation method comprises the steps of stirring and filtering a polyamide resin prepolymer in a nonsolvent containing at least one of ethanol, ethyl acetate, and dichloropentafluoropropane; And solid-phase-polymerizing the filtered prepolymer.

In an embodiment, the polyamide resin prepolymer is polycondensed by reacting a dicarboxylic acid component and a diamine component at a temperature of 200 to 300 DEG C and a pressure of 10 to 40 bar under an inert gas atmosphere at a temperature of 15 to 30 DEG C And 0 to 3 bar conditions.

In an embodiment, the polyamide resin prepolymer is dissolved in a 98% sulfuric acid solution at a concentration of 0.5 g / dl, and the intrinsic viscosity (IV) measured at 25 ° C using a Ubbelodhde viscometer is 0.05 to 0.30 dL / g. < / RTI >

In embodiments, the polyamide resin prepolymer may have an average particle size of from 0.01 to 100 [mu] m.

In an embodiment, the amount of the non-solvent may be 200 to 1,000 parts by weight based on 100 parts by weight of the polyamide resin prepolymer.

In an embodiment, the stirring temperature may be between 15 and 30 < 0 > C.

In an embodiment, the solid state polymerization can be carried out at a temperature of 200 to 300 DEG C and a pressure of 0.001 to 0.1 bar.

An object of the present invention is to provide a method for producing a polyamide resin which can economically remove unreacted raw materials, reaction by-products and the like from a pre-solid state polyamide resin prepolymer to improve the color and thermal properties of the polyamide resin Effect.

Hereinafter, the present invention will be described in detail.

The method for producing a polyamide resin according to the present invention comprises the steps of stirring and filtering a polyamide resin prepolymer into a nonsolvent containing at least one of ethanol, ethyl acetate and dichloropentafluoropropane; And solid-phase-polymerizing the filtered prepolymer.

The polyamide resin prepolymer according to one embodiment of the present invention may be a polyamide resin prepolymer obtained through a polycondensation reaction of a conventional dicarboxylic acid component and a diamine component.

In the present specification, the dicarboxylic acid component includes dicarboxylic acid, its alkyl ester (lower alkyl ester having 1 to 4 carbon atoms such as monomethyl ester, monoethyl ester, dimethyl ester, diethyl ester or dibutyl ester) Acid anhydride and the like, and react with the diamine component to form a dicarboxylic acid moiety diamine moiety, respectively. Here, the dicarboxylic acid moiety and the diamine moiety mean a residue remaining after the hydrogen atom, the hydroxyl group or the alkoxy group is removed when the dicarboxylic acid component and the diamine component are polymerized.

In an embodiment, the dicarboxylic acid component includes terephthalic acid, isophthalic acid, 2,6-naphthalene dicarboxylic acid, 2,7-naphthalene dicarboxylic acid, 1,4-naphthalene dicarboxylic acid, 1,4 - phenylene dioxydiacetic acid, 1,3-phenylenedioxydiacetic acid, diphenic acid, 4,4'-oxydibenzoic acid, diphenylmethane-4,4'-dicarboxylic acid, diphenylsulfone-4,4 Aromatic dicarboxylic acid components such as dicarboxylic acid and 4,4'-biphenyldicarboxylic acid; But are not limited to, maleic acid, malonic acid, dimethyl malonic acid, succinic acid, glutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimeric acid, Aliphatic dicarboxylic acid components such as acid, azelaic acid, sebacic acid, undecanedioic acid, and dodecanedioic acid; Alicyclic dicarboxylic acid components such as 1,3-cyclopentanedicarboxylic acid and 1,4-cyclohexanedicarboxylic acid; But the present invention is not limited thereto. These dicarboxylic acid components may be used alone or in combination of two or more kinds, for example, an aromatic dicarboxylic acid component such as terephthalic acid and an aliphatic dicarboxylic acid component such as adipic acid.

In an embodiment, the diamine component may be selected from the group consisting of ethylenediamine, propanediamine, 1,4-butanediamine, 1,6-hexanediamine (hexamethylenediamine), 1,7-heptanediamine, 1,3-butanediamine, 1,9-nonanediamine, 1,10-decanediamine, 1,11-undecanediamine, 1,12-dodecanediamine, 1,6-hexanediamine, 2,4,4-trimethyl-1,6-hexanediamine, 2-methyl-1,8-octanediamine, Aliphatic diamine components such as diamines; (4-aminocyclohexyl) methane, 1,3-bisaminomethylcyclohexane, 1,4-bisaminomethylcyclohexane, norbornanedimethanamine, trioctanedimethanamine, Alicyclic diamine components such as cyclodecane dimethanamine; Aromatic diamine components such as paraphenylenediamine, metaphenylenediamine, 4,4'-diaminodiphenylsulfone, and 4,4'-diaminodiphenyl ether; But the present invention is not limited thereto. These dicarboxylic acid components may be used alone or in combination of two or more.

In an embodiment, the molar ratio (diamine / dicarboxylic acid) of the diamine component and the dicarboxylic acid component used in the polycondensation reaction may be 0.9 to 1.3, for example, 0.95 to 1.25. Within the above range, deterioration of physical properties due to excess unreacted monomers can be prevented.

In a specific example, the polyamide resin prepolymer can be produced by adding the dicarboxylic acid component and the diamine component to, for example, a commonly used pressure polymerization vessel and performing a polycondensation reaction with stirring in an aqueous solvent. More specifically, the dicarboxylic acid component and the diamine component are stirred at a temperature of 200 to 300 DEG C, for example, 220 to 235 DEG C and 10 to 40 bar, for example, 15 to 40 bar Condensation reaction is carried out in a polymerization vessel under pressure conditions, and it is discharged and cooled in an inert gas atmosphere at a temperature of 15 to 30 DEG C, for example, at 20 to 25 DEG C and 0 to 3 bar, for example, at 1 to 2 bar Can be manufactured.

Here, the aqueous solvent is a solvent containing water as a main component. The solvent that can be used in addition to water is not particularly limited as long as it does not affect the polycondensation reactivity or solubility, and for example, alcohols such as methanol, ethanol, propanol, butanol and ethylene glycol can be used.

In an embodiment, the amount of water in the reaction system at the time of starting the polycondensation reaction may be an amount such that the water content in the reaction system at the completion of the reaction is 15 to 35% by weight. For example, the water content in the reaction system when initiating the polycondensation reaction may be from 17 to 60% by weight. It is possible to reduce the thermal deterioration of the lower condensation product (prepolymer) due to the prolongation of the reaction time without requiring a time and energy for distilling off the water in the polycondensation step in the above-mentioned moisture content range.

In a specific example, a phosphorus-based catalyst (phosphorus compound) may be used in order to improve the polycondensation rate and prevent deterioration during the polycondensation reaction in the production of the prepolymer. As the phosphorus-based catalyst, there may be used hypophosphite, phosphite, phosphate, hypophosphorous acid, phosphorous acid, phosphoric acid, phosphoric acid ester, polymetalic acid, polyphosphoric acid, phosphinoxide, phosphonium halide and mixtures thereof . For example, hypophosphite, phosphite, phosphate, hypophosphorous acid, phosphorous acid, phosphoric acid, and mixtures thereof can be used. Specifically, hypophosphite, phosphate, hypophosphorous acid, phosphoric acid and mixtures thereof can be used. The addition amount of the phosphorus-containing catalyst may be 0.1 to 1.0 part by weight, for example, 0.2 to 0.5 part by weight based on 100 parts by weight of the total amount of the dicarboxylic acid component and the diamine component. It is preferable that the adding time of the phosphorus-containing catalyst is between the time of injecting the raw material and the completion of polycondensation of the prepolymer. The catalyst may be added at least once, or two or more different phosphorus-containing catalysts may be added in combination.

In an embodiment, the polycondensation reaction can be carried out in the presence of a terminal blocking agent. When the end sealant is used, the molecular weight of the prepolymer (lower condensation product) is more easily controlled and the melt stability can be improved. The terminal endblocking agent is not particularly limited as long as it is a monofunctional compound having reactivity with the terminal amino group or terminal carboxyl group of the prepolymer. For example, an acid anhydride such as monocarboxylic acid, monoamine, phthalic anhydride, Mono-acid halides, monoesters, mono-alcohols and the like can be used. The end-cap encapsulant may be used alone or in combination of two or more. Among the above-mentioned terminal sealing agents, a monocarboxylic acid or a monoamine is preferably used as a terminal endblocker from the viewpoints of reactivity and stability of a sealing end, and monocarboxylic acid can be more preferably used because it is easy to handle. The amount of the end-use encapsulant may vary depending on the reactivity, boiling point, reaction apparatus, reaction conditions, etc. of the end-use encapsulant used. For example, the amount of the end encapsulant may range from 0.1 to 100 parts by mol based on 100 parts by mol of the dicarboxylic acid component and / 15 mole fraction.

In an embodiment, in the polycondensation reaction of the prepolymer, the reaction temperature can be controlled after injection of the raw material, and the reaction pressure can be controlled in accordance with the progress of the polymerization. In the above process, the reaction temperature may be 200 to 300 ° C, for example, 220 to 235 ° C, and the reaction pressure may be 10 to 40 bar, for example, 15 to 40 bar. In this temperature range, the prepolymer can be efficiently obtained without side reactions such as gelation, and the temperature in the reaction system or the water content in the reaction system can be easily controlled in the above-mentioned pressure range, and the prepolymer can be easily discharged. Further, the polycondensation reaction can be carried out for 0.5 to 4 hours, for example, for 1 to 3 hours. Within this range, a sufficient degree of polymerization can be attained, and a high-quality prepolymer can be obtained without giving excessive heat history.

In the polycondensation reaction, the water content in the reaction system at the completion of the reaction of the prepolymer may be from 15 to 35% by weight, for example, from 20 to 35% by weight. Here, the term "reaction completion" refers to a time point at which the discharge operation of the prepolymer (lower condensate) having reached the predetermined degree of polymerization is started, and the water content is the amount of the condensation water generated during the reaction. In order to adjust the water content to the above range, a water amount combined with the generated condensation water may be injected, or a predetermined amount of water may be distilled off by adjusting the reaction pressure in an apparatus equipped with a condenser, a pressure regulating valve or the like. Within the above range, precipitation or solidification of the prepolymer in the reaction system hardly occurs, and after the completion of the reaction, the prepolymer can be easily discharged.

The polycondensation reaction can be carried out in a batch or continuous manner, and is preferably carried out under stirring in order to prevent adhesion of the prepolymer and uniform progress of the polycondensation reaction.

Next, in order to obtain the polyamide resin prepolymer according to one embodiment of the present invention, the prepolymer having completed the polycondensation reaction may be discharged and cooled from the reaction vessel. For example, a prepolymer prepared from a reaction system (reaction vessel) at a temperature of 200 to 300 ° C and a pressure condition of 10 to 40 bar is reacted under an inert gas atmosphere at a temperature of 15 to 30 ° C, for example, 15 to 25 ° C, (Withdrawal) and cooling to a container (flasher) of 3 bar, for example 1 to 2 bar condition. Within this range, it is possible to efficiently obtain a prepolymer having a nonvolatile powdery form (powdery or granular form) which is easy to remove the solvent from the prepolymer, sufficiently secure the cooling time, and has a high volume specific gravity.

In an embodiment, the inert gas atmosphere may be an oxygen concentration of 1% by volume or less in order to prevent oxidation and deterioration of the prepolymer, and the discharge rate of the prepolymer from the reaction vessel may be controlled by controlling the scale of the reaction vessel, (Ejection) such that the ejection speed is in the range of 10 to 50 m / sec, although it can be appropriately adjusted in accordance with the amount, the temperature, the size of the ejection port, the length of the ejection nozzle, Within the above range, the solvent removal and cooling time can be sufficiently secured.

In embodiments, the discharged and cooled polyamide resin prepolymer may have various shapes and sizes (e.g., an average particle size of 0.01 to 100 mu m), and may be compacted compacting treatment or particle (powder) treatment can be further performed. For example, the polyamide resin prepolymer may have an average particle size of 0.01 to 100 mu m, for example, 0.1 to 10 mu m. In the above range, removal of the unreacted monomers, side reactants and the like from the prepolymer (separation from the non-solvent) can be facilitated.

In an embodiment, the polyamide resin prepolymer is dissolved in a 98% sulfuric acid solution at a concentration of 0.5 g / dl, and the intrinsic viscosity (IV) measured at 25 ° C using a Ubbelodhde viscometer is 0.05 to 0.30 dL / g, for example from 0.10 to 0.25 dL / g. Within the above range, precipitation of the prepolymer and fixation in the reaction system can be suppressed during the polycondensation reaction, and fusion bonding of the particles during the prepolymer solid state polymerization and adhesion in the apparatus can be suppressed.

In the process for producing a polyamide resin according to the present invention, the step of stirring and filtering the polyamide resin prepolymer into a non-solvent containing at least one of ethanol, ethyl acetate and dichloropentafluoropropane, Is a pre-solid-phase polymerization pretreatment step for removing unreacted materials, side reactions, In the pretreatment step, unreacted materials and side reactants can be melted during the polycondensation reaction, and the polyamide resin prepolymer can be easily obtained from the polyamide resin prepolymer by simply stirring and filtering using the non- Unreacted materials, nonreactive materials, and the like can be removed.

In an embodiment, the non-solvent is a solubility in the polyamide resin prepolymer of 0.05 g / 100 ml (non-solvent), for example, 0.001 to 0.01 g / 100 ml (non-solvent), and the dicarboxylic acid component , Diamine component, minor reactant, etc. may be 1 g / 100 ml (non-solvent) or more, for example, 1 to 5 g / 100 ml (non-solvent). In the above range, unreacted materials, side reactants, and the like can be removed from the polyamide resin prepolymer without re-precipitation of the prepolymer.

In an embodiment, the dichloropentafluoropropane in the non-solvent may be 3,3-dichloro-1,1,1,2,2-pentafluoropropane (3,3-dichloro-1,1,1,2- AK225 which is a mixture of 1,3-dichloro-1,1,2,2,3-pentafluoropropane and 1,3-dichloro-1,1,2,2,3-pentafluoropropane : Asahi glass), but the present invention is not limited thereto.

In an embodiment, the amount of the non-solvent may be 200 to 1,000 parts by weight, for example, 300 to 500 parts by weight, based on 100 parts by weight of the polyamide resin prepolymer. Unreacted materials, side reactants and the like contained in the polyamide resin prepolymer within the above range can be sufficiently removed.

In an embodiment, the stirring temperature may be from 15 to 30 캜, for example from 20 to 30 캜, and the stirring time may be from 0.5 to 4 hours, for example from 1 to 2 hours. Unreacted materials, side reactants and the like contained in the polyamide resin prepolymer within the above range can be sufficiently removed.

In an embodiment, after completion of the stirring of the polyamide resin prepolymer and the non-solvent, the polyamide resin prepolymer may be filtrated by a conventional method, and if necessary, the filtered polyamide resin prepolymer may be dried , A compacting process or a particle (powder) process can be further performed.

In the process for producing a polyamide resin according to the present invention, a polyamide resin is produced by subjecting the prepolymer thus filtered to high polymerization by solid state polymerization (SSP). The solid phase polymerization can be carried out in the same manner as the conventional solid phase polymerization.

In the specific examples, the solid-state polymerization may be carried out in an inert gas atmosphere such as helium gas, argon gas, nitrogen gas, carbonic acid gas and the like in order to prevent oxidation and deterioration of the prepolymer and the polyamide resin to be produced. Deg.] C, for example 210 to 245 [deg.] C, and a pressure of from 0.001 to 0.1 bar, for example, from 0.001 to 0.01 bar. Within this range, a high molecular weight polyamide resin can be obtained in a high yield, and thermal discoloration of the produced polyamide resin can be minimized. The reaction time in the solid phase polymerization is not particularly limited, but may be generally from 1 to 20 hours. During the solid phase polymerization reaction, the prepolymer may be mechanically stirred, or may be stirred using a gas stream.

In a specific example, a conventional solid phase polymerization apparatus can be used as the solid phase polymerization apparatus without limitation. Specific examples of the solid-state polymerization apparatus include, for example, a single-shaft disk type, a kneader, a two-axis paddle type, a vertical type column type apparatus, a vertical type column type apparatus, a rotary drum type or a double cone type solid- But is not limited thereto.

The method for producing a polyamide resin according to the present invention can easily remove unreacted materials, side reactants, and the like during polycondensation through a simple pretreatment process (non-solvent, stirring and filtration) after preparing a polyamide resin prepolymer, Solid state polymerization is carried out by using a prepolymer from which an unreacted material or the like has been removed to obtain a final polymer (polyamide resin) having excellent yield, color and thermal properties.

Hereinafter, the configuration and operation of the present invention will be described in more detail with reference to preferred embodiments of the present invention. It is to be understood, however, that the same is by way of illustration and example only and is not to be construed in a limiting sense.

Example

Examples 1 to 4 and Comparative Examples 1 to 3: Preparation of polyamide resin

According to the compositions shown in Tables 1 and 2, terephthalic acid (TPA) and adipic acid (AA) and a diamine component (diamine) were added to a 1 liter autoclave as a dicarboxylic acid diacid Hexamethylenediamine (HMDA) was added. Then, 1.5 molar parts of acetic acid as a terminal endblocker, 0.1 part of sodium hypophosphonate as a catalyst, and 38 wt% of water were added to 100 molar parts of the dicarboxylic acid component and the diamine component The part was filled with nitrogen. Next, the reaction was carried out at 230 DEG C and 22 bar for 2 hours to prepare a prepolymer in the solution. Next, the prepolymer in the solution was injected at a spraying rate of 15 m / s through a nozzle of a flash machine (internal temperature: 20 ° C, internal pressure: 1 bar, cylindrical, height: 0.5 m, volume: 0.004 m ³ ) , And the solvent (water) was removed to prepare a polyamide resin prepolymer. 100 parts by weight of the prepared polyamide resin prepolymer was added to the non-solvent and the solvent of 300 parts by weight in the following Tables 1 and 2, stirred at 25 캜 for 1 hour, and then filtered. Next, the resulting polyamide resin prepolymer was poured into a round bottom flask, placed in a rotary evaporator equipped with an oil bath, purged with nitrogen, immersed in an oil bath while rotating the flask under nitrogen flow at 1 l / min, , The internal temperature was raised to 230 캜 over 1 hour, and then solid phase polymerization was carried out at the same temperature for 5 hours. After a predetermined reaction time had elapsed, the reaction mixture was cooled to room temperature (25 DEG C) to obtain a polyamide resin having a high polymerization degree.

Comparative Examples 4 to 5: Preparation of polyamide resin

The polyamide resins of Comparative Examples 4 and 5 were prepared in the same manner as in Examples 1 and 2, except that stirring and filtration were not performed using the non-solvent.

How to measure property

(1) Measurement of Intrinsic Viscosity (IV) (unit: dL / g): Measured by using a Ubbelodhde viscometer at 25 ° C after dissolving in a 98% sulfuric acid solution at a concentration of 0.5 g / dl.

(2) Color measurement: L *, a *, b * and yellowness index (YI) were measured using a CM-2600d colorimeter of Konica Minolta.

(3) Average particle size measurement (unit: 占 퐉): The average particle size of the powdery polyamide resin prepolymer was measured using an optical microscope.

(4) Melting temperature (unit: 占 폚): Nitrogen was flowed at a flow rate of 10 ml / min in an amorphous sample using DSC manufactured by Seiko Instrument Co., To 350 DEG C, followed by holding for 5 minutes, and measurement was carried out up to 100 DEG C at a cooling rate of 10 DEG C / min. The endothermic peak temperature due to melting at the time of heating was measured as the melting temperature.

Example One 2 3 4 Diacid TPA (mol%) 45 50 45 45 AA (mol%) 55 50 55 55 Diamine HMDA (mol%) 100 100 100 100 The mole ratio (Diamine / Diacid) 1.013 Used cost AK225 AK225 EA EtOH Prepolymerization properties before solid phase polymerization IV 0.08 dl / g 0.09 dl / g 0.08 dl / g 0.08 dl / g L * 96.90 95.76 97.24 97.74 a * -0.04 -0.05 -0.11 -0.07 b * 3.46 3.86 3.41 2.28 YI 5.16 5.81 5.05 3.34 Average particle size 1 ㎛ 1 ㎛ 1 ㎛ 1 ㎛ Polyamide resin property IV 0.79 dl / g 0.83 dl / g 0.82 dl / g 0.80 dl / g L * 96.60 92.72 92.85 92.64 a * -0.98 -1.00 0.65 -0.84 b * 5.17 5.56 4.45 4.60 YI 8.98 9.78 9.31 7.81 The melting temperature (Tm) 308 ° C 310 ° C 308 ° C 308 ° C Filterability good good good good

(AK225 (product name): dichloro-fluoropropane mixed solvent (manufacturer: asahi glass), EA: ethyl acetate, EtOH: ethanol)

Comparative Example One 2 3 4 5 Diacid TPA (mol%) 45 45 45 45 50 AA (mol%) 55 55 55 55 50 Diamine HMDA (mol%) 100 100 100 100 100 The mole ratio (Diamine / Diacid) 1.013 Used solvent Methanol water Benzyl alcohol - - Prepolymerization properties before solid phase polymerization IV 0.08 dl / g 0.08 dl / g 0.08 dl / g 0.08 dl / g 0.09 dl / g L * 95.49 92.97 93.47 93.75 93.85 a * 0.15 0.29 -0.66 0.08 0.09 b * 5.38 9.05 7.02 7.46 7.85 YI 8.13 14.00 10.63 11.33 12.11 Average particle size 1 ㎛ 1 ㎛ 1 ㎛ 1 ㎛ 1 ㎛ Polyamide resin property IV 0.80 dl / g 0.79 dl / g 0.82 dl / g 0.83 dl / g 0.81 dl / g L * 94.26 92.53 92.32 93.34 92.32 a * -1.52 -1.67 -1.89 -1.98 -1.53 b * 14.22 17.09 13.05 15.79 15.32 YI 20.24 23.31 21.12 23.67 22.32 The melting temperature (Tm) 303 ℃ 304 ℃ 304 ℃ 305 ℃ 307 ° C Filterability Not good Not good Not good - -

From the above results, in Examples 1 to 4, unreacted materials and byproducts of the prepolymer were removed by the non-solvent without the reprecipitation step, and the color was improved after solid-phase polymerization as compared with Comparative Examples 4 and 5, . In addition, Comparative Examples 1 to 3 using methanol, water and benzyl alcohol instead of the non-solvent of the present invention were found to have a viscosity increase due to dissolution of the prepolymer when using a solvent (water, methanol, benzyl alcohol, etc.) , It was not easy to separate the prepolymer from the solvent without the reprecipitation step, which makes it difficult to remove unreacted materials and byproducts, and does not improve color, melting temperature, and the like.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

Stirring and filtering the polyamide resin prepolymer into a non-solvent containing at least one of ethanol, ethyl acetate, and dichloropentafluoropropane; And
And subjecting the filtered prepolymer to solid-state polymerization.

The polyamide resin prepolymer according to claim 1, wherein the polyamide resin prepolymer is subjected to a polycondensation reaction between the dicarboxylic acid component and the diamine component at a temperature of 200 to 300 ° C and a pressure of 10 to 40 bar, And then discharged and cooled to a container at 30 DEG C and 0 to 3 bar.

The polyamide resin prepolymer of claim 1, wherein the polyamide prepolymer is dissolved in a 98% sulfuric acid solution at a concentration of 0.5 g / dl, and the intrinsic viscosity (IV) of the prepolymer measured using a Ubbelodhde viscometer at 25 & 0.30 dL / g. &Lt; / RTI >

The method for producing a polyamide resin according to claim 1, wherein the polyamide resin prepolymer has an average particle size of 0.01 to 100 탆.

The method for producing a polyamide resin according to claim 1, wherein the amount of the non-solvent is from 200 to 1,000 parts by weight based on 100 parts by weight of the polyamide resin prepolymer.

The process for producing a polyamide resin according to claim 1, wherein the stirring temperature is 15 to 30 占 폚.

The method for producing a polyamide resin according to claim 1, wherein the solid state polymerization is carried out at a temperature of 200 to 300 ° C and a pressure of 0.001 to 0.1 bar.