Method for preparing capped poly(phenylene oxide)

Abstract

The present invention relates to a method for preparing capped poly(phenylene oxide) and, more specifically, to a method for preparing capped poly(phenylene oxide), which can improve the filterability of capped poly(phenylene oxide) while reducing coprecipitated impurities, and has a low level of polar impurities.

Description

Method for preparing capped poly(phenylene oxide)

[0001] This application claims priority to Republic of Korea Patent Application No. 10-2024-0030932, filed with the Korean Intellectual Property Office on March 4, 2024, the disclosure of which is incorporated herein by reference.

[0002] The present invention relates to a method for preparing capped poly(phenylene oxide), and more particularly, to a method for preparing capped poly(phenylene oxide) comprising reacting uncapped poly(phenylene oxide) with an anhydride capping agent, followed by a plurality of crystallization steps.

[0003] Poly(phenylene oxide) (poly(phenylene ether)) polymers are resins with excellent water resistance and dimensional stability, a wide temperature range, and excellent dielectric properties. They are used in a variety of products, such as machine parts, insulating layers, electronic products, and automotive components, through various crosslinking agents and copolymerization. In particular, capped poly(phenylene oxide), which is a telechelic polymer with active terminal groups and is made by capping a curable functional group at the terminal, can be used in the manufacture of electronic devices due to its lower moisture absorption and improved physical properties through curing.

[0004] According to Korean Patent No. 10-0832928, moisture can cause damage during the manufacturing of electronic devices, and this moisture was found to increase as the amount of polar impurities in the polymer composition increased. Polar impurities can originate from residual catalysts, reaction byproducts, or reagents during the manufacturing process using capping agents, and the residual amount can vary depending on the manufacturing method. Conventional methods for manufacturing capped poly(phenylene oxide) include methods using anhydride capping agents and amine catalysts. Since anhydride capping agents hydrolyze to produce organic acids, they produce impurities with higher polarity than amine catalysts or capping agents.

[0005] According to a conventionally known purification method, as disclosed in Korean Patent No. 10-0832928, an organic solvent containing capped poly(phenylene oxide) is crystallized in an antisolvent (alkanol) to separate organic amines, anhydride capping agents, and reaction byproducts, thereby producing a composition containing 1,000 ppm of an organic amine catalyst and 10,000 ppm or less of an organic acid.

[0006] And, according to another purification method known in the past, according to U.S. Patent No. 7,595,367, a composition containing an organic amine catalyst of 1,000 ppm or less and acrylic acid of 2,500 ppm or less can be prepared by extracting and purifying polar impurities from an organic solvent containing capped poly(phenylene oxide) using a basic aqueous solution and an acidic aqueous solution.

[0007] The crystallization method described in Korean Patent No. 10-0832928 leaves a small amount of capping anhydride residue, which can be hydrolyzed by moisture introduced in subsequent processes, resulting in increased organic acid content and polar impurities. Furthermore, while the crystallization method can control the organic amine catalyst concentration below 1,000 ppm, the organic acid, the most polar reaction byproduct, is produced at a concentration below 10,000 ppm, resulting in significant residual amounts. Furthermore, toluene, used as a reaction solvent, is an environmentally regulated substance, making it unfriendly.

[0008] In addition, the water washing method described in U.S. Patent No. 7,595,367 can manage organic amine catalysts and organic acids to less than 1,000 ppm and 2,500 ppm, respectively, but there are conditions in which layer separation is not good due to emulsion depending on the purification conditions, and there is a drawback in that a large amount of wastewater is generated because water washing is performed multiple times to manage impurities below the standard. Furthermore, there is a problem in that the presence of ions that may remain when using inorganic acids or inorganic bases may affect post-processing or the properties of the final product.

[0009] [Prior Art Literature]

[0010] [Patent Document]

[0011] (Patent Document 0001) Republic of Korea Patent No. 10-0832928

[0012] (Patent Document 0002) U.S. Patent No. 7595367

[0013] Accordingly, the technical problem to be achieved by the present invention is to provide a method for producing capped poly(phenylene oxide) that does not generate a large amount of wastewater, is environmentally friendly by excluding environmentally regulated substances such as BTX (benzene, toluene, xylene), does not contain anhydrides in the product, and thus does not increase impurities during post-processing and storage, and has a low level of polar impurities.

[0014] In addition, the present invention provides a method for producing capped poly(phenylene oxide) with improved filterability while reducing coprecipitated impurities by including two crystallization steps.

[0015] And, the technical problem to be achieved by the present invention is to provide a thermosetting composition comprising a capped poly(phenylene oxide) manufactured according to the above-described method for manufacturing a capped poly(phenylene oxide) and an olefin-based unsaturated monomer.

[0016] The problems to be solved by the present invention are not limited to the problems mentioned above, and other problems not mentioned will be clearly understood by those skilled in the art from the description below.

[0017] According to one aspect of the present invention, a method for producing a capped poly(phenylene oxide) is provided, including: (S10) a step of introducing poly(phenylene oxide) and a catalyst into a first solvent, dissolving the poly(phenylene oxide) in the first solvent to prepare a first reactant; (S20) a step of heating a second reactant, in which an anhydride capping agent is introduced into the first reactant, to a boiling point and then stirring at a reflux temperature; (S30) a step of introducing a viscosity reducing agent into the resultant of the step (S20) and stirring it; (S40) a first crystallization step of adding the resultant of the step (S30) dropwise to a second solvent and stirring it; and (S50) a second crystallization step of adding a third solvent dropwise to the resultant of the step (S40) and stirring it.

[0018] At this time, the capped poly(phenylene oxide) may have a structure represented by the following chemical formula 1.

[0019] [Chemical Formula 1]

[0020] Y(BA) x

[0021] (In the above chemical formula 1, Y is a residue of monovalent, divalent or polyvalent phenol;

[0022] B contains a repeating unit of the following chemical formula 2;

[0023] A is a capping group prepared by reaction of the anhydride capping agent and a free phenolic hydroxyl group on the poly(phenylene oxide);

[0024] x is between 1 and 100.)

[0025] [Chemical Formula 2]

[0026]

[0027] (In the above chemical formula 2, m is 1 to 200;

[0028] R1 and R3 are independently selected from the group consisting of hydrogen, halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbyloxy and C2-C12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen atom and the oxygen atom);

[0029] R2 and R4 are independently selected from the group consisting of halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbyloxy and C2-C12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen atom and the oxygen atom).

[0030] Here, the above A may represent any one of the structures of Chemical Formula 3 to Chemical Formula 5 below.

[0031] [Chemical Formula 3]

[0032]

[0033] (In the above chemical formula 3, R5 is C1-C12 hydrocarbyl optionally substituted with one or two carboxylic acid groups.)

[0034] [Chemical Formula 4]

[0035]

[0036] (In the above chemical formula 4, R6 to R8 are independently selected from the group consisting of hydrogen, C1-C18 hydrocarbyl optionally substituted with one or two carboxylic acid groups, C2-C18 hydrocarbyloxycarbonyl, nitrile, formyl, carboxylic acid, imidate, and thiocarboxylic acid.)

[0037] [Chemical Formula 5]

[0038]

[0039] (In the above chemical formula 5, R9 to R 13 are independently selected from the group consisting of hydrogen, halogen, C1-C12 alkyl, hydroxy, amino and carboxylic acid.)

[0040] And, the above Y may represent the structure of the following chemical formula 6.

[0041] [Chemical Formula 6]

[0042]

[0043] (In the above chemical formula 6, L represents a structure of any one of the following chemical formulas 7 to 13;

[0044] z can be 0 or 1;

[0045] R1 to R4 are independently selected from the group consisting of hydrogen, halogen and substituted C1-C12 hydrocarbyl.

[0046] [Chemical Formula 7]

[0047]

[0048] [Chemical Formula 8]

[0049]

[0050] (In the above chemical formula 8, R5 is selected from the group consisting of hydrogen and C1-C12 hydrocarbyl.)

[0051] [Chemical Formula 9]

[0052]

[0053] [Chemical Formula 10]

[0054]

[0055] [Chemical Formula 11]

[0056]

[0057] [Chemical Formula 12]

[0058]

[0059] [Chemical Formula 13]

[0060]

[0061] (In the above chemical formula 13, R6 and R7 are independently selected from the group consisting of hydrogen, C1-C12 hydrocarbyl, and C1-C6 hydrocarbylene.)

[0062] And, the first solvent may be an aprotic solvent.

[0063] At this time, the aprotic solvent may include one selected from the group consisting of ethyl acetate, propylene glycol methyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone, and benzyl phenyl ketone, or a mixture of two or more thereof.

[0064] Additionally, the anhydride capping agent may have a structure represented by the following chemical formula 14.

[0065] [Chemical Formula 14]

[0066]

[0067] (In the above chemical formula 14, Y independently represents a structure of any one of the following chemical formulas 15 to 17.)

[0068] [Chemical Formula 15]

[0069]

[0070] (In the above chemical formula 15, R5 is C1-C12 hydrocarbyl optionally substituted with one or two carboxylic acid groups.)

[0071] [Chemical Formula 16]

[0072]

[0073] (In the above chemical formula 16, R6 to R8 are independently selected from the group consisting of hydrogen, C1-C18 hydrocarbyl optionally substituted with one or two carboxylic acid groups, C2-C18 hydrocarbyloxycarbonyl, nitrile, formyl, carboxylic acid, imidate, and thiocarboxylic acid.)

[0074] [Chemical Formula 17]

[0075]

[0076] (In the above chemical formula 17, R9 to R 13 are independently selected from the group consisting of hydrogen, halogen, C1-C12 alkyl, hydroxy, amino and carboxylic acid.)

[0077] In addition, the anhydride capping agent may include one selected from the group consisting of acetic anhydride, succinic anhydride, maleic anhydride, salicylic anhydride, phthalic anhydride, acrylic anhydride, and methacrylic anhydride, or a mixture of two or more thereof.

[0078] And, the content of the anhydride capping agent may be 10 to 50 parts by weight based on 100 parts by weight of the poly(phenylene oxide).

[0079] Meanwhile, the viscosity reducing agent may include one selected from the group consisting of C1-C4 alkanols or a mixture of two or more thereof.

[0080] And, the content of the viscosity reducing agent may be 1 to 30 parts by weight based on 100 parts by weight of the poly(phenylene oxide).

[0081] In addition, the second solvent and the third solvent may independently comprise one selected from the group consisting of C1-C4 alkanols or a mixture of two or more thereof.

[0082] And, the content of the second solvent and the third solvent may be, independently of each other, 200 to 400 parts by weight based on 100 parts by weight of the poly(phenylene oxide).

[0083] Meanwhile, the method for producing capped poly(phenylene oxide) according to the present invention is performed after the step (S50), and may further include the step (S60) of filtering the result of the step (S50) to obtain a solid product, and then washing the solid product with a washing solution.

[0084] At this time, the washing liquid may contain alkanol and water.

[0085] Here, the washing liquid may contain 1 to 30 parts by weight of water based on 100 parts by weight of the alkanol.

[0086] And, after the step (S60), the step (S70) may further include a step of drying the solid obtained product at a temperature of 80 to 100° C. to remove residual solvent.

[0087] According to one embodiment of the present invention, the filterability of capped poly(phenylene oxide) can be improved while reducing coprecipitated impurities by including two crystallization steps.

[0088] In addition, it is environmentally friendly as it does not generate a large amount of wastewater during the manufacturing process, excludes environmentally regulated substances such as BTX (benzene, toluene, xylene), does not contain anhydrides in the product, and thus does not increase impurities during post-processing and storage, and can obtain a capped poly(phenylene oxide) with a low level of polar impurities.

[0089] Meanwhile, the effects of the present invention are not limited to the above-described effects, and should be understood to include all effects that can be inferred from the detailed description of the present invention or the composition of the invention described in the claims.

[0090] Hereinafter, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention.

[0091] The embodiments of the present invention described below are provided to more clearly explain the present invention to a person having ordinary skill in the art, and the scope of the present invention is not limited by the following embodiments, and the following embodiments can be modified in various other forms.

[0092] The terminology used herein is used to describe particular embodiments and is not intended to limit the present invention. The singular forms used herein may include the plural forms unless the context clearly dictates otherwise. In addition, the terms "comprise" and / or "comprising" used herein specify the presence of a stated feature, step, number, operation, element, element, and / or group thereof, but do not exclude the presence or addition of one or more other features, steps, numbers, operations, elements, elements, and / or groups thereof. In addition, the term "connected" used herein not only means that certain elements are directly connected, but also includes a concept that indirectly connects elements by interposing another element between them.

[0093] In addition, when it is said in this specification that a certain element is located "on" another element, this includes not only cases where a certain element is in contact with another element, but also cases where another element exists between the two elements. The term "and / or" as used in this specification includes any one of the listed items and any and all combinations of one or more of them. In addition, terms of degree such as "about", "substantially", etc. as used in this specification are used to mean a range of or close to the numerical value or degree, taking into account inherent manufacturing and material tolerances, and are used to prevent infringers from unfairly using the disclosure that mentions exact or absolute numbers provided to help the understanding of this specification.

[0094]

[0095] A method for producing a capped poly(phenylene oxide) according to one aspect of the present invention comprises: (S10) preparing a first reactant by introducing poly(phenylene oxide) and a catalyst into a first solvent and dissolving the poly(phenylene oxide) in the first solvent; (S20) heating a second reactant, in which an anhydride capping agent is introduced into the first reactant, to a boiling point and then stirring at a reflux temperature; (S30) introducing a viscosity reducing agent into the resultant of step (S20) and stirring; (S40) a first crystallization step of adding the resultant of step (S30) dropwise to a second solvent and stirring; and (S50) a second crystallization step of adding a third solvent dropwise to the resultant of step (S40) and stirring.

[0096] As in one embodiment of the present invention, including two crystallization steps has the advantage of reducing the impurities that may be coprecipitated and improving the filterability of the capped poly(phenylene oxide).

[0097] The capped poly(phenylene oxide) according to the present invention may have a structure represented by the following chemical formula 1.

[0098] [Chemical Formula 1]

[0099] Y(BA) x

[0100] In the above chemical formula 1, Y may be a residue of a monovalent, divalent or polyvalent phenol;

[0101] B may include a repeating unit of the following chemical formula 2;

[0102] A may be a capping group prepared by reaction of the anhydride capping agent and a free phenolic hydroxyl group on the poly(phenylene oxide);

[0103] x can be between 1 and 100.

[0104] [Chemical Formula 2]

[0105]

[0106] In the above chemical formula 2, m may be 1 to about 200, specifically 2 to about 200;

[0107] R1 and R3 can be independently selected from the group consisting of hydrogen, halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbyloxy and C2-C12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen atom from the oxygen atom or other atom);

[0108] R2 and R4 can be independently selected from the group consisting of halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbyloxy and C2-C12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen atom from the oxygen atom or other atom).

[0109] Here, A in the above chemical formula 1 may represent any one of the structures of the following chemical formulas 3 to 5.

[0110] [Chemical Formula 3]

[0111]

[0112] In the above chemical formula 3, R5 may be a C1-C12 hydrocarbyl group optionally substituted with one or two carboxylic acid groups, etc.

[0113] [Chemical Formula 4]

[0114]

[0115] In the above chemical formula 4, R6 to R8 can be independently selected from the group consisting of hydrogen, C1-C18 hydrocarbyl optionally substituted with one or two carboxylic acid groups, C2-C18 hydrocarbyloxycarbonyl, nitrile, formyl, carboxylic acid, imidate, and thiocarboxylic acid.

[0116] [Chemical Formula 5]

[0117]

[0118] In the above chemical formula 5, R9 to R 13 may be independently selected from the group consisting of hydrogen, halogen, C1-C12 alkyl, hydroxy, amino and carboxylic acid.

[0119] And, the Y in the above chemical formula 1 may represent the structure of the following chemical formula 6.

[0120] [Chemical Formula 6]

[0121]

[0122] In the above chemical formula 6, L can represent any one of the structures of the following chemical formulas 7 to 13;

[0123] z can be 0 or 1;

[0124] R1 to R4 can be independently selected from the group consisting of hydrogen, halogen and substituted C1-C12 hydrocarbyl.

[0125] [Chemical Formula 7]

[0126]

[0127] [Chemical Formula 8]

[0128]

[0129] In the above chemical formula 8, R5 can be selected from the group consisting of hydrogen and C1-C12 hydrocarbyl.

[0130] [Chemical Formula 9]

[0131]

[0132] [Chemical Formula 10]

[0133]

[0134] [Chemical Formula 11]

[0135]

[0136] [Chemical Formula 12]

[0137]

[0138] [Chemical Formula 13]

[0139]

[0140] In the above chemical formula 13, R6 and R7 can be independently selected from the group consisting of hydrogen, C1-C12 hydrocarbyl, and C1-C6 hydrocarbylene.

[0141] The term "hydrocarbyl" as used herein refers to a moiety containing only carbon and hydrogen. This moiety may be aliphatic or aromatic, straight-chain, cyclic, bicyclic, branched, saturated, or unsaturated. However, when described as such, the hydrocarbyl moiety may contain heteroatoms on the carbon and hydrogen members of the substituent moiety. Thus, when specifically indicated as containing such heteroatoms, the hydrocarbyl moiety may also contain a carbonyl group, an amino group, a hydroxyl group, a halogen atom, or the like, or it may contain heteroatoms within the main chain of the hydrocarbyl moiety.

[0142] (S10) The catalyst used in the step may include compounds known in the art for the condensation reaction of anhydride and phenol. Useful materials include, but are not limited to, basic compounds including hydroxide salts such as sodium hydroxide, potassium hydroxide, and tetraalkylammonium hydroxide; tertiary alkylamines such as tributylamine, triethylamine, dimethylbenzylamine, dimethylbutylamine, and the like; tertiary mixed alkyl-arylamines and substituted derivatives thereof such as N,N-dimethylaniline; Heterocyclic amines, such as imidazole, pyridine and their substituted derivatives, such as 2-methylimidazole, 2-vinyl imidazole, 4-dimethylaminopyridine, 4-(1-pyrrolino)pyridine, 4-(1-pyrrolino)pyridine, 4-(1-piperidino)pyridine, 2-vinylpyridine, 3-vinylpyridine and 4-vinylpyridine.

[0143] More specifically, 4-dimethylaminopyridine (DMAP) may be used. The content of the catalyst may be 0.1 to 10 parts by weight, specifically 1 to 8 parts by weight, and even more specifically 2 to 7 parts by weight, based on 100 parts by weight of poly(phenylene oxide), but is not limited thereto.

[0144] In addition, the first solvent used as a reaction solvent in the capping reaction of the present invention may be an aprotic solvent, and examples thereof include one selected from the group consisting of ethyl acetate, propylene glycol methyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone, and benzyl phenyl ketone, or a mixture of two or more thereof, but is not limited thereto.

[0145] More specifically, ethyl acetate can be used. The content of the ethyl acetate may be 100 to 400 parts by weight, specifically 150 to 350 parts by weight, and even more specifically 200 to 300 parts by weight, based on 100 parts by weight of poly(phenylene oxide), but is not limited thereto.

[0146] The anhydride capping agent used in step (S20) may have a structure represented by the following chemical formula 14.

[0147] [Chemical Formula 14]

[0148]

[0149] In the above chemical formula 14, Y can independently represent any one of the structures of the following chemical formulas 15 to 17.

[0150] [Chemical Formula 15]

[0151]

[0152] In the above chemical formula 15, R5 may be a C1-C12 hydrocarbyl group optionally substituted with one or two carboxylic acid groups.

[0153] [Chemical Formula 16]

[0154]

[0155] In the above chemical formula 16, R6 to R8 can be independently selected from the group consisting of hydrogen, C1-C18 hydrocarbyl optionally substituted with one or two carboxylic acid groups, C2-C18 hydrocarbyloxycarbonyl, nitrile, formyl, carboxylic acid, imidate, and thiocarboxylic acid.

[0156] [Chemical Formula 17]

[0157]

[0158] In the above chemical formula 17, R9 to R 13 may be independently selected from the group consisting of hydrogen, halogen, C1-C12 alkyl, hydroxy, amino and carboxylic acid.

[0159] Specific examples of the anhydride capping agent may include one selected from the group consisting of acetic anhydride, succinic anhydride, maleic anhydride, salicylic anhydride, phthalic anhydride, acrylic anhydride, and methacrylic anhydride, or a mixture of two or more thereof.

[0160] The above anhydride capping agent may additionally be understood to include a dicarboxylic acid capable of forming a corresponding cyclic anhydride under capping reaction conditions. Such dicarboxylic acids may include, for example, maleic acid, malic acid, citraconic acid, itaconic acid, and phthalic acid.

[0161] More specifically, methacrylic anhydride may be used. The content of the anhydride capping agent may be 10 to 50 parts by weight, specifically 15 to 40 parts by weight, and even more specifically 20 to 35 parts by weight, based on 100 parts by weight of poly(phenylene oxide), but is not limited thereto. If it is lower than 20 parts by weight, the conversion rate may not be achieved and the physical properties may change, and if it exceeds 35 parts by weight, byproducts may increase due to the use of excessive raw materials, which is not preferable.

[0162] And, in the step (S20), the second reactant may be heated to a boiling point and then stirred at a reflux temperature for 1 to 20 hours, 2 to 18 hours, 3 to 16 hours, or 5 to 15 hours, but is not limited thereto.

[0163] After the above step (S20) (i.e., the capping reaction step), the reaction mixture becomes somewhat suspended and the viscosity increases due to the byproducts generated by the anhydride capping agent and the catalyst. The mixture with increased viscosity does not crystallize smoothly during crystallization, and polar impurities co-precipitate inside. Since it is not easy to remove the impurities from the co-precipitated particles even by washing, it is important to relieve the viscosity of the reaction mixture. Methods for reducing the viscosity of the reaction mixture include raising the temperature of the reaction mixture and adding a viscosity reducing agent. Increasing the temperature at the production site requires a lot of energy and process time, which leads to a decrease in process efficiency. Therefore, the use of a viscosity reducing agent is more preferable.

[0164] The substance used as the viscosity reducing agent may include one selected from the group consisting of C1-C4 alkanols or a mixture of two or more thereof.

[0165] The C1-C4 alkanol can be methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, tert-butanol, ethylene glycol, propylene glycol, 1,4-butanediol, glycerol, or a combination thereof.

[0166] More specifically, methanol may be used. The content of the viscosity reducing agent may be 1 to 30 parts by weight, specifically 5 to 25 parts by weight, and even more specifically 10 to 25 parts by weight, based on 100 parts by weight of the poly(phenylene oxide), but is not limited thereto.

[0167] Furthermore, an additional advantage of using the viscosity reducing agent immediately after the capping reaction is that the unreacted anhydride capping agent can be removed. The anhydride capping agent remaining after the capping reaction is alcoholyzed by the alkanol, and is mostly removed, so that it does not remain in the product after crystallization. According to conventionally known techniques, crystallization mostly occurs at room temperature or below, and in alcohols with large molecular weights, such as isopropanol, the anhydride capping agent takes a long time to decompose, resulting in its remaining presence. Therefore, using the viscosity reducing agent at a high temperature immediately after the capping reaction has the advantage of being able to decompose the anhydride capping agent quickly.

[0168] Specifically, the temperature at which the viscosity reducing agent is added may be 30 to 80°C, specifically 40 to 70°C, and more specifically 50 to 60°C, but is not limited thereto.

[0169]

[0170] Meanwhile, according to one embodiment of the present invention, it is characterized by including two crystallization steps, thereby improving the filterability of the capped poly(phenylene oxide) while reducing coprecipitated impurities.

[0171] With respect to the first and second crystallization steps (i.e., steps (S40) and (S50)), the first crystallization is carried out by adding a reaction mixture containing a capped poly(phenylene oxide) dropwise to a second solvent and stirring. Then, the second crystallization is carried out by adding a third solvent dropwise to the resultant of the first crystallization step and stirring.

[0172] At this time, the second solvent and the third solvent may independently comprise one selected from the group consisting of C1-C4 alkanols or a mixture of two or more thereof. The second solvent and the third solvent may specifically be methanol.

[0173] In addition, the content of the second solvent and the third solvent may be, independently of each other, 200 to 500 parts by weight based on 100 parts by weight of the poly(phenylene oxide), specifically 300 to 400 parts by weight, and more specifically about 350 parts by weight, but is not limited thereto.

[0174] The above first crystallization step should be performed at a low temperature, as a high temperature may cause the capped poly(phenylene oxide) crystals to clump together. Specifically, the above first crystallization step may be performed by cooling the resultant of the above step (S30) to room temperature, and then adding it dropwise to a second solvent at a temperature of -20 to 20°C, more specifically -5 to 15°C, while stirring.

[0175] In addition, the second crystallization step should also be performed at a low temperature, and specifically, the second crystallization step can be performed by adding the third solvent dropwise to the resultant product of the step (S40) at a temperature of -20 to 20°C, more specifically -5 to 15°C, and stirring the resultant product.

[0176] Once the crystallization step is complete, the capped poly(phenylene oxide) crystals can be filtered using a filter or the like, thereby obtaining a solid product in the form of a wet cake. The type of filter is not particularly limited, and a Nutsche filter, filter press, filter and dryer, centrifugal device, etc. can be used.

[0177] After the above crystallization step (i.e., step (S40) and step (S50)) is completed, a step of (S60) filtering the result of the crystallization step to obtain a solid product, and then washing the solid product with a washing solution may be further included. This washing operation may use a washing solution containing alkanol and water that was used as an antisolvent.

[0178] Although there is no difference in the cleaning effect compared to anhydrous alcohol, by increasing the polarity of the cleaning solution, the decrease in the yield during the cleaning can be prevented. More specifically, since capped poly(phenylene oxide) is an oligomer or polymer, not a monomer with a single molecular weight, there is a molecular weight distribution range that can be dissolved in alkanol. In addition, immediately after filtration, the solubility tends to increase because a small amount of the reaction solvent with good solubility is contained in the wet cake phase. If anhydrous alkanol is used, the low molecular weight region is dissolved and washed away, which can result in changes in the product properties and a decrease in the yield. Therefore, it is desirable to use a mixture of water and alkanol to increase the polarity of the cleaning solvent.

[0179] The above-mentioned cleaning solution may contain 1 to 30 parts by weight of the water based on 100 parts by weight of the alkanol, specifically 1 to 20 parts by weight, and more specifically 1 to 10 parts by weight, but is not limited thereto. Here, the alkanol may specifically be methanol.

[0180] Meanwhile, according to the present invention, after the step (S60), a step (S70) of drying the solid obtained product at a temperature of 80 to 100° C. to remove residual solvent may be further included.

[0181] After filtration and washing of the capped poly(phenylene oxide) is completed, it can be dried to remove residual solvent. The drying method is not particularly limited, but reduced pressure drying is preferred for drying efficiency, and a ribbon dryer, filter and dryer, tray dryer, etc. can be used. Specifically, when a ribbon dryer is used, drying can be performed at a temperature of 50 to 100°C. If the drying temperature is lower than the above numerical range, drying efficiency may decrease and it may take a long time, which is not preferred.

[0182] The product after the above drying process is a solid resin, and ultimately, a capped poly(phenylene oxide) having a low polar impurity level can be manufactured.

[0183]

[0184] Hereinafter, the present invention will be described in detail with examples to specifically illustrate it. However, the examples according to the present invention may be modified in various ways, and the scope of the present invention should not be construed as being limited to the examples described below. These examples are provided to more fully explain the present invention to those of average skill in the art.

[0185]

[0186] 1. Preparation of capped poly(phenylene oxide)

[0187] (1) Example 1

[0188] In a reactor equipped with a cooling reflux tube and a stirrer, 100 g of uncapped poly(phenylene oxide) (hereinafter, PPO-2OH), 5 g of 4-dimethylaminopyridine (hereinafter, DMAP), and 250 g of ethyl acetate (hereinafter, EA) as a first solvent were placed and stirred.

[0189] After 30 minutes, when PPO-2OH had dissolved, 30 g of methacrylic anhydride (MAAH) was added and the temperature was raised to the boiling point.

[0190] At reflux temperature, the reaction was terminated after 10 hours. After completion of the reaction, the internal temperature was cooled to 50 to 60°C, and 20 g of methanol (MeOH) was added as a viscosity reducing agent. A small amount of crystals splattered, but quickly dissolved, and the mixture was stirred for 1 hour.

[0191] After the above reaction solution was cooled back to room temperature, it was added dropwise to 300 g of methanol, the second solvent in the second reactor, to carry out the first crystallization step. The temperature of the first crystallization step was 5°C and stirred for 1 hour, and thereafter, 300 g of methanol, the third solvent, was added dropwise to the resultant of the first crystallization step to carry out the second crystallization step. The temperature of the second crystallization step was 5°C and stirred for 1 hour.

[0192] After crystallization was completed, the resultant of the second crystallization step was filtered through a glass filter, and the filtrate was sufficiently removed, followed by washing with a 95 wt% methanol aqueous solution mixed with water. The washed capped poly(phenylene oxide) resin was dried under reduced pressure at 90°C for 12 hours, and finally, a capped poly(phenylene oxide) resin was obtained.

[0193]

[0194] (2) Example 2

[0195] A capped poly(phenylene oxide) resin was obtained in the same manner as in Example 1, except that anhydrous methanol was used as the washing solution instead of a mixture of water and methanol.

[0196]

[0197] (3) Comparative Example 1

[0198] A capped poly(phenylene oxide) resin was obtained in the same manner as in Example 1, except that methanol, a viscosity reducing agent, was not added.

[0199]

[0200] (4) Comparative Example 2

[0201] A capped poly(phenylene oxide) resin was obtained in the same manner as in Example 1, except that crystallization was performed using 600 g of the second solvent and the second crystallization step using the third solvent was omitted.

[0202]

[0203] (5) Comparative Example 3

[0204] A capped poly(phenylene oxide) resin was obtained in the same manner as in Example 1, except that no washing was performed.

[0205]

[0206] (6) Comparative Example 4

[0207] 100 g of PPO-2OH, 5 g of DMAP, and 100 g of toluene as the first solvent were added to a reactor equipped with a cooling reflux tube and a stirrer, and stirred. After 30 minutes, when PPO-2OH had dissolved, 30 g of MAAH was added, and the temperature was increased to the boiling point.

[0208] At reflux temperature, the reaction was terminated after 10 hours. After completion of the reaction, the mixture was washed with 50 g of a 5 wt% NaOH aqueous solution at 50 to 60°C, and the lower aqueous layer was discarded through layer separation. The upper organic layer was washed again with 50 g of an acidic aqueous solution (5 wt% acetic acid), and the layers were separated.

[0209] After the organic layer was cooled back to room temperature, it was added dropwise to 600 g of methanol in the second reactor to proceed with the crystallization step. The temperature of the crystallization step was 5 ℃, stirred for 1 hour, and after the crystallization was completed, the result of the crystallization step was filtered through a glass filter, and the filtrate was sufficiently removed, and then washed with a 95 wt% methanol aqueous solution washing solution mixed with water. The capped poly(phenylene oxide) resin that had been washed was dried under reduced pressure at 90 ℃ for 12 hours, and finally the capped poly(phenylene oxide) resin was obtained.

[0210]

[0211] (7) Comparative Example 5

[0212] A capped poly(phenylene oxide) resin was obtained in the same manner as in Comparative Example 4, except that washing and layer separation were performed with a basic or acidic aqueous solution, and isopropanol (hereinafter, IPA) was used instead of methanol as the solvent (antisolvent) in the second reactor.

[0213]

[0214] 2. Evaluation of physical properties of capped poly(phenylene oxide)

[0215] (1) Measurement of Mw (weight average molecular weight)

[0216] Using Shimadzu GPC LC-40D / RID-20A equipment, after setting Agilent PLegl 5㎛ 1,000 Å + 500 Å + 100 Å, molecular weight calibration was performed using the standard method, and then molecular weight was measured.

[0217]

[0218] (2) Measurement of impurity content

[0219] Using an Agilent HPLC 1260 series instrument, an Atlantis dC18 column (4.6 x 150 mm, 5 ㎛) was set, and impurities in capped poly(phenylene oxide) (MPPO, Modified PPO) were quantitatively analyzed using methacrylic acid (MAA) and 4-dimethylaminopyridine (DMAP) standards.

[0220]

[0221] (3) Gel-time measurement

[0222] A 0.3 g sample of the resin composition was placed on a hot plate at approximately 191°C, and the time required for the sample to no longer stick to the stirring rod used to stir the sample or for the sample to harden was measured.

[0223]

[0224] (4) Adhesion test (Peeling test)

[0225] The force required to vertically peel a 1 cm wide copper foil from the laminate was measured.

[0226]

[0227] (5) Hardening behavior and delamination behavior

[0228] Curing behavior: The powder obtained from the prepreg was measured using a TA Rheometer, and the viscosity change due to curing was observed in the temperature range from 60 ℃ to 160 ℃ at a heating rate of 3 ℃ / min.

[0229] Layer separation behavior: When approximately 1 L of organic and aqueous solutions were stirred at 200 RPM or higher for 30 minutes and then allowed to settle, the degree of layer separation was visually confirmed and measured over time. If the organic and aqueous layers were clearly separated within 10 minutes, the degree of layer separation was evaluated as good. If the layer separation at the interface was not good even after 10 minutes or more, or if the organic or aqueous layers were turbid (haziness), the degree of layer separation was evaluated as poor.

[0230] Example 1 Example 2 Yield (%) 9188 Mw (AMU) 4,214 4,391 Methacrylic Anhydride (ppm) NDND Methacrylic Acid (ppm) 1,012 1,130 DMAP (ppm) 212 208 Gel-time (sec) 96.5 10 5.4 Peeling test (lb / in) 3.4 0 3.37 Curing Behavior Well Cured Well Cured Delamination Behavior Not applicable Not applicable

[0231] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Yield (%) 9 190 917 186 Mw (AMU) 4,24 24,198 4,139 4,32 24,268 Methacrylic Anhydride (ppm) (24) *NDNDND192Methacrylic acid (ppm)2,4372,8447,9724,3085,322DMAP (ppm)6558541,7311,816931Gel-time (sec)98.197.795.3-96.9Peeling test (lb / in)3.253.292.71-2.91Cure behaviorWell curedWell curedDifferent behaviorDifferent behaviorDelamination behaviorNot applicableNot applicableNot applicableOrganic phase emulsifiedNot applicable

[0232] *Based on wet cake

[0233] Referring to Tables 1 and 2, the resin manufactured by Example 1 did not detect methacrylic anhydride, and methacrylic acid was manufactured at 1,500 ppm or less. In particular, DAMP was detected at 500 ppm or less, confirming that a significant amount was removed. In addition, the resin manufactured by Example 2 removed polar impurities similarly to Example 1, but the yield was slightly reduced. This can be seen as the dissolution of the low-molecular-weight resin. The curing behavior was similar, but the gel time increased slightly, which can be seen as the decrease in low molecular weight, resulting in a decrease in the number of functional groups that can be cured per unit weight.

[0234] Meanwhile, the resin manufactured by Comparative Example 1 was capable of manufacturing a sufficiently small amount of DMAP, but methacrylic acid was detected at a significantly high level of 2,500 ppm. This can be seen as a result of crystallization in a high viscosity state, and polar impurities coprecipitated within the long molecular chains and did not dissolve well. In addition, a very small amount of methacrylic anhydride was detected in the product in a wet cake state before drying, but was not detected after drying. This can be seen as a result of the omission of the quenching process using a viscosity reducing agent, so that a small amount remained and was then volatilized and removed under high drying temperatures.

[0235] The resin manufactured by Comparative Example 2 contained 2,844 ppm of methacrylic acid, a significantly higher amount than that of Example 1. If crystallization is not performed in two stages, the crystal growth stage is omitted and crystals are precipitated at once, so the probability of coprecipitation is relatively high, and as a result, methacrylic acid is not sufficiently removed.

[0236] The resin manufactured in Comparative Example 3 was not washed, so it contained a large amount of residual methacrylic acid and DMAP. The gel time was similar, but it exhibited a different curing behavior than Example 1. This is believed to be due to the large amount of methacrylic acid. Furthermore, it exhibited the poorest adhesion in the peeling test, which is also believed to be due to the large amount of methacrylic acid.

[0237] The resin manufactured by Comparative Example 4 was purified through workup (washing) to compare the results of different purification methods. However, a large amount of emulsion was generated during layer separation, resulting in a very long separation time. Furthermore, the yield decreased significantly during the process of removing the emulsion layer. Furthermore, due to poor layer separation, a large amount of methacrylic acid and DMAP remained.

[0238] The resin manufactured by Comparative Example 5 exhibited a decrease in yield due to increased solubility when crystallized using toluene / IPA, and a significant amount of residual impurities from coprecipitation. Additionally, a small amount of MAAH was detected, likely due to the lower reactivity of IPA compared to methanol.

[0239]

[0240] This specification has disclosed preferred embodiments of the present invention, and although specific terms have been used, they are used in a general sense only to easily explain the technical contents of the present invention and to help understand the invention, and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of ​​the present invention are possible in addition to the embodiments disclosed herein. For example, those skilled in the art will recognize that the method for preparing capped poly(phenylene oxide) according to the embodiments can be modified in various ways. Therefore, the scope of the invention should not be defined by the described embodiments, but should be defined by the technical idea described in the claims.

Claims

1. (S10) A step of preparing a first reactant by introducing poly(phenylene oxide) and a catalyst into a first solvent and dissolving the poly(phenylene oxide) in the first solvent; (S20) A step of heating the second reactant, in which an anhydride capping agent is added to the first reactant, to the boiling point and then stirring at a reflux temperature; (S30) A step of adding a viscosity reducing agent to the result of the above step (S20) and stirring it; (S40) A first crystallization step of adding the result of the above step (S30) to a second solvent and stirring; and (S50) A method for producing capped poly(phenylene oxide) comprising a second crystallization step of adding a third solvent dropwise to the resultant of step (S40) and stirring.

2. In paragraph 1, A method for producing capped poly(phenylene oxide), wherein the capped poly(phenylene oxide) has a structure represented by the following chemical formula 1. [Chemical Formula 1] And(BA) x (In the above chemical formula 1, Y is a residue of monovalent, divalent or polyvalent phenol; B contains a repeating unit of the following chemical formula 2; A is a capping group prepared by reaction of the anhydride capping agent and a free phenolic hydroxyl group on the poly(phenylene oxide); x is between 1 and 100.) [Chemical Formula 2] (In the above chemical formula 2, m is 1 to 200; R1 and R3 are independently selected from the group consisting of hydrogen, halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbyloxy and C2-C12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen atom and the oxygen atom); R2 and R4 are independently selected from the group consisting of halogen, primary or secondary C1-C12 alkyl, C2-C12 alkenyl, C2-C12 alkynyl, C1-C12 aminoalkyl, C1-C12 hydroxyalkyl, phenyl, C1-C12 haloalkyl, C1-C12 hydrocarbyloxy and C2-C12 halohydrocarbyloxy (wherein at least two carbon atoms separate the halogen atom and the oxygen atom).

3. In paragraph 2, A method for producing a capped poly(phenylene oxide), wherein the above A represents a structure represented by any one of the following chemical formulas 3 to 5. [Chemical Formula 3] (In the above chemical formula 3, R5 is C1-C12 hydrocarbyl optionally substituted with one or two carboxylic acid groups.) [Chemical Formula 4] (In the above chemical formula 4, R6 to R8 are independently selected from the group consisting of hydrogen, C1-C18 hydrocarbyl optionally substituted with one or two carboxylic acid groups, C2-C18 hydrocarbyloxycarbonyl, nitrile, formyl, carboxylic acid, imidate, and thiocarboxylic acid.) [Chemical Formula 5] (In the above chemical formula 5, R9 to R 13 are independently selected from the group consisting of hydrogen, halogen, C1-C12 alkyl, hydroxy, amino and carboxylic acid.) 4. In paragraph 2, A method for producing capped poly(phenylene oxide), wherein the above Y represents a structure of the following chemical formula 6. [Chemical Formula 6] (In the above chemical formula 6, L represents a structure of any one of the following chemical formulas 7 to 13; z can be 0 or 1; R1 to R4 are independently selected from the group consisting of hydrogen, halogen and substituted C1-C12 hydrocarbyl. [Chemical Formula 7] [Chemical Formula 8] (In the above chemical formula 8, R5 is selected from the group consisting of hydrogen and C1-C12 hydrocarbyl.) [Chemical Formula 9] [Chemical Formula 10] [Chemical Formula 11] [Chemical Formula 12] [Chemical Formula 13] (In the above chemical formula 13, R6 and R7 are independently selected from the group consisting of hydrogen, C1-C12 hydrocarbyl, and C1-C6 hydrocarbylene.) 5. In paragraph 1, A method for producing capped poly(phenylene oxide), wherein the first solvent is an aprotic solvent.

6. In paragraph 5, A method for producing a capped poly(phenylene oxide), wherein the aprotic solvent comprises one selected from the group consisting of ethyl acetate, propylene glycol methyl ether acetate, methyl ethyl ketone, methyl isobutyl ketone, and benzyl phenyl ketone, or a mixture of two or more thereof.

7. In paragraph 1, A method for producing capped poly(phenylene oxide), wherein the anhydride capping agent has a structure represented by the following chemical formula 14. [Chemical Formula 14] (In the above chemical formula 14, Y independently represents a structure of any one of the following chemical formulas 15 to 17.) [Chemical Formula 15] (In the above chemical formula 15, R5 is C1-C12 hydrocarbyl optionally substituted with one or two carboxylic acid groups.) [Chemical Formula 16] (In the above chemical formula 16, R6 to R8 are independently selected from the group consisting of hydrogen, C1-C18 hydrocarbyl optionally substituted with one or two carboxylic acid groups, C2-C18 hydrocarbyloxycarbonyl, nitrile, formyl, carboxylic acid, imidate, and thiocarboxylic acid.) [Chemical Formula 17] (In the above chemical formula 17, R9 to R 13 are independently selected from the group consisting of hydrogen, halogen, C1-C12 alkyl, hydroxy, amino and carboxylic acid.) 8. In paragraph 1, A method for producing a capped poly(phenylene oxide), wherein the anhydride capping agent comprises one selected from the group consisting of acetic anhydride, succinic anhydride, maleic anhydride, salicylic anhydride, phthalic anhydride, acrylic anhydride, and methacrylic anhydride, or a mixture of two or more thereof.

9. In paragraph 1, A method for producing capped poly(phenylene oxide), wherein the content of the anhydride capping agent is 10 to 50 parts by weight based on 100 parts by weight of the poly(phenylene oxide).

10. In paragraph 1, A method for producing a capped poly(phenylene oxide), wherein the viscosity reducing agent comprises one selected from the group consisting of C1-C4 alkanols or a mixture of two or more thereof.

11. In paragraph 1, A method for producing capped poly(phenylene oxide), wherein the content of the viscosity reducing agent is 1 to 30 parts by weight based on 100 parts by weight of the poly(phenylene oxide).

12. In paragraph 1, A method for producing a capped poly(phenylene oxide), wherein the second solvent and the third solvent independently comprise one selected from the group consisting of C1-C4 alkanols or a mixture of two or more thereof.

13. In paragraph 1, A method for producing capped poly(phenylene oxide), wherein the contents of the second solvent and the third solvent are, independently of each other, 200 to 400 parts by weight based on 100 parts by weight of the poly(phenylene oxide).

14. In paragraph 1, It is performed after the above step (S50), (S60) A method for producing capped poly(phenylene oxide), further comprising a step of filtering the result of step (S50) to obtain a solid product, and then washing the solid product with a washing solution.

15. In paragraph 14, A method for producing capped poly(phenylene oxide), wherein the above washing solution comprises alkanol and water.

16. In paragraph 15, A method for producing capped poly(phenylene oxide), wherein the washing solution contains 1 to 30 parts by weight of water based on 100 parts by weight of the alkanol.

17. In paragraph 14, It is performed after the above step (S60), (S70) A method for producing capped poly(phenylene oxide), further comprising a step of drying the solid obtained at a temperature of 80 to 100°C to remove residual solvent.