Polyetherester copolymer and method for producing same

Abstract

The present invention relates to a polyetherester copolymer comprising a polymer matrix containing polyether repeating units and polyester repeating units; and a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid remaining in the polymer matrix; and a method for producing the same.

Description

[Technical Field]

[0001] (CROSS-REFERENCE TO RELATED APPLICATIONS) This application claims the benefit of priority based on Korean Patent Application No. 10-2022-0168705 dated December 6, 2022, and all contents disclosed in the documents of that Korean patent application are incorporated herein by reference.

[0002] The present invention relates to a polyetherester copolymer that can significantly reduce polymerization time and increase productivity while maintaining excellent physical properties of the copolymer, and a method for producing the same. [Background technology]

[0003] Thermoplastic poly(ether ester) elastomers (TPEEs) are high-performance materials that combine the elasticity of rubber with the moldability of plastics, and are used in a wide range of fields, including automobiles, home appliances, building materials, IT, and everyday items, replacing vulcanized rubber and PVC (polyvinyl chloride). A typical example of TPEE is a polyether ester block copolymer resin composition.

[0004] Polyetherester copolymers have the properties of an elastomer, consisting of a hard segment composed of a diol and a dicarboxylic acid derivative and a soft segment composed of a polyetherdiol and a dicarboxylic acid derivative. The hard segment provides the mechanical properties of the elastomer, while the soft segment provides the elasticity and flexibility of the elastomer.

[0005] Such thermoplastic polyetherester copolymers are commercially produced by a two-step reaction of diol, dicarboxylate, and polyetherdiol as raw materials, which involves an ester exchange reaction followed by polycondensation of the reaction product.

[0006] For example, polybutylene terephthalate (PBT)-poly(tetramethylene ether glycol; PTMG) copolymer, a well-known TPEE, is produced from 1,4-butylene glycol (BG), dimethyl terephthalate (DMT), and PTMG as starting materials through a transesterification reaction and condensation polymerization process.

[0007] Meanwhile, in the polycondensation step, in order to improve productivity, a co-catalyst can be additionally used in addition to the main catalyst, and as such a co-catalyst, an alkali metal salt or an alkaline earth metal salt such as sodium acetate (Na-acetate), magnesium acetate (Mg acetate), or calcium acetate (Ca acetate) has been mainly used.

[0008] However, in the process using the existing cocatalyst, it is difficult to sufficiently shorten the polymerization time, and the productivity still decreases, making it unsuitable for mass production.

[0009] Therefore, there is a need for a method for producing polyetherester copolymers that can produce polyetherester copolymers that maintain similar thermal and mechanical properties to conventional copolymers while shortening the polymerization time sufficiently to make them suitable for mass production. Summary of the Invention [Problem to be solved by the invention]

[0010] The present invention provides a polyetherester copolymer that can significantly reduce the polymerization time and increase productivity while maintaining excellent physical properties of the copolymer.

[0011] The present invention also provides a method for producing the polyetherester copolymer. [Means for solving the problem]

[0012] In order to solve the above problems, the present specification provides a polyetherester copolymer including: a polymer matrix including polyether-based repeating units and polyester-based repeating units; and a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid remaining in the polymer matrix.

[0013] Also provided herein is a method for producing a polyether ester copolymer, comprising: a) an esterification reaction step of reacting a diol, a dicarboxylic acid or a derivative thereof, and a polyether diol in the presence of a catalyst and a co-catalyst; b) a first condensation polymerization step of adding a catalyst to the reaction mixture obtained after the completion of step a) and carrying out condensation polymerization under reduced pressure to produce a prepolymer; and c) a second condensation polymerization step of condensing the prepolymer under a pressure condition lower than that of step b), wherein the co-catalyst comprises a monometal salt of an inorganic acid and a multimetal salt of an inorganic acid.

[0014] The polyetherester copolymer and the method for producing the same according to specific embodiments of the invention will be described in more detail below.

[0015] Unless expressly stated otherwise herein, terminology is for the purpose of referring to particular embodiments only and is not intended to be limiting of the invention.

[0016] As used herein, the singular forms "a," "an," and "the" include the plural forms as well, unless the context clearly dictates to the contrary.

[0017] As used herein, the meaning of "comprising" embodies certain properties, regions, integers, steps, operations, elements, and / or components, and does not exclude the presence or addition of other certain properties, regions, integers, steps, operations, elements, components, and / or groups.

[0018] In this specification, terms including ordinal numbers, such as "first" and "second," are used to distinguish one component from another, and are not limited by the ordinal numbers. For example, within the scope of the present invention, a first component may be named a second component, and similarly, a second component may be named a first component.

[0019] In this specification, examples of the substituents are explained below, but the present invention is not limited to these.

[0020] As used herein, the term "substituted" means that another functional group is bonded in place of a hydrogen atom in a compound, and the position of substitution is not limited as long as it is a position at which a hydrogen atom is substituted, i.e., a position at which a substituent can be substituted, and when two or more substituents are substituted, the two or more substituents may be the same or different.

[0021] As used herein, the term "substituted or unsubstituted" refers to a group substituted or unsubstituted with one or more substituents selected from the group consisting of deuterium, halogen, cyano, nitro, hydroxy, carbonyl, ester, imide, amide, primary amino, carboxy, sulfonic acid, sulfonamide, phosphine oxide, alkoxy, aryloxy, alkylthioxy, arylthioxy, alkylsulfoxy, arylsulfoxy, silyl, boron, alkyl, cycloalkyl, alkenyl, aryl, aralkyl, aralkenyl, alkylaryl, alkoxysilylalkyl, arylphosphine, or heterocyclic groups containing one or more N, O, and S atoms, or a group substituted or unsubstituted with two or more of the above-listed substituents linked together. For example, a "substituent linked to two or more substituents" may be a biphenyl group. In other words, a biphenyl group may be an aryl group or may be interpreted as a substituent linked to two phenyl groups.

[0022] In this specification, [ka] or [ka] means a bond connecting to another substituent, and a direct bond means that there is no other atom in the moiety represented by L.

[0023] In this specification, aromaticity refers to a property that satisfies the Huckels Rule, and according to the Huckels Rule, a compound can be defined as aromatic if it satisfies all of the following three conditions:

[0024] 1) There must be 4n+2 electrons in complete conjugation via hollow p-orbitals, unsaturated bonds, unpaired electron pairs, etc.

[0025] 2) The 4n+2 electrons must form a planar isomer and must form a ring structure.

[0026] 3) All atoms of the ring must be able to participate in conjugation.

[0027] In this specification, aliphatic can be defined as aliphatic when it does not satisfy the above-mentioned aromaticity.

[0028] In this specification, the alkyl group is a monovalent functional group derived from an alkane, and may be linear or branched, and the number of carbon atoms in the linear alkyl group is not particularly limited, but is preferably 1 to 20. Furthermore, the number of carbon atoms in the branched alkyl group is 3 to 20. Exemplary alkyl groups include, but are not limited to, methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methylbutyl, 1-ethylbutyl, pentyl, n-pentyl, isopentyl, neopentyl, tert-pentyl, hexyl, n-hexyl, 1-methylpentyl, 2-methylpentyl, 4-methyl-2-pentyl, 3,3-dimethylbutyl, 2-ethylbutyl, heptyl, n-heptyl, 1-methylhexyl, octyl, n-octyl, tert-octyl, 1-methylheptyl, 2-ethylhexyl, 2-propylpentyl, n-nonyl, 2,2-dimethylheptyl, 1-ethylpropyl, 1,1-dimethylpropyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl, 2,6-dimethylheptan-4-yl, and the like. The alkyl group may be substituted or unsubstituted, and when substituted, examples of the substituent are as described above.

[0029] As used herein, a cycloalkyl group refers to a monovalent functional group derived from a cycloalkane, and may be monocyclic or polycyclic. It has 3 to 20 carbon atoms, but is not limited thereto. According to another embodiment, the cycloalkyl group has 3 to 10 carbon atoms. Specific examples include, but are not limited to, cyclopropyl, cyclobutyl, cyclopentyl, 3-methylcyclopentyl, 2,3-dimethylcyclopentyl, cyclohexyl, 3-methylcyclohexyl, 4-methylcyclohexyl, 2,3-dimethylcyclohexyl, 3,4,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, cycloheptyl, cyclooctyl, and bicyclo[2,2,1]heptyl. The cycloalkyl group may be substituted or unsubstituted. If substituted, examples of the substituent are as described above.

[0030] In this specification, the aryl group is a monovalent functional group derived from arene, and is not particularly limited. It preferably has 6 to 20 carbon atoms and may be a monocyclic aryl group or a polycyclic aryl group. The monocyclic aryl group may be, but is not limited to, a phenyl group, a biphenyl group, a terphenyl group, etc. The polycyclic aryl group may be, but is not limited to, a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, a chrysenyl group, a fluorenyl group, etc. The aryl group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.

[0031] In this specification, an alkylene group is a divalent functional group derived from an alkane, and the above description of the alkyl group is applicable, except that it is a divalent functional group. For example, it may be linear or branched, and may be a methylene group, ethylene group, propylene group, isobutylene group, sec-butylene group, tert-butylene group, pentylene group, hexylene group, etc. The alkylene group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.

[0032] In this specification, an arylene group is a divalent functional group derived from arene, and the above description of the aryl group is applicable, except that it is a divalent functional group. For example, it may be a phenylene group, biphenylene group, terphenylene group, naphthalene group, fluorenyl group, pyrenyl group, phenanthrenyl group, perylene group, tetracenyl group, anthracenyl group, etc. The arylene group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.

[0033] In this specification, the cycloalkylene group is a divalent functional group derived from a cycloalkane, and the above description of the cycloalkyl group is applicable except that it is a divalent functional group. The cycloalkylene group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.

[0034] In this specification, a derivative compound means a compound that has been modified from a certain organic compound by introducing a functional group, oxidation, reduction, atomic substitution, etc., within the limits that do not significantly change the structure and properties of the parent compound.

[0035] The present invention will now be described in more detail.

[0036] 1. Polyetherester copolymer According to one embodiment of the invention, there is provided a polyetherester copolymer comprising: a polymeric matrix including polyether-based repeating units and polyester-based repeating units; and a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid remaining in the polymeric matrix.

[0037] The present inventors have confirmed through experiments that, as in the polyetherester copolymer of the above embodiment, by adding a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid as a co-catalyst during synthesis of the polyetherester copolymer, the production efficiency of the polyetherester copolymer can be improved while maintaining excellent physical properties, and have completed the invention.

[0038] The monometallic salt of an inorganic acid and the multimetallic salt of an inorganic acid can be added as a co-catalyst together with the monomers diol, dicarboxylic acid or derivatives thereof, and polyether diol, and the main catalyst during the synthesis of the polyether ester copolymer, and some or all of the co-catalyst can remain in the final synthesized polyether ester copolymer.

[0039] Specifically, the polyetherester copolymer can include a polymeric matrix that includes polyether-based repeating units and polyester-based repeating units.

[0040] The polyether repeating unit refers to a repeating unit containing a polyether functional group in the repeating unit structure, and specifically may have a structure represented by the following Chemical Formula 1.

[0041] [ka]

[0042] In the above Chemical Formula 1, R1 is one of an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 3 to 10 carbon atoms, and an arylene group having 6 to 20 carbon atoms, R2 is an alkylene group having 1 to 10 carbon atoms, and n is an integer of 1 to 100.

[0043] As a more specific example, in the above Chemical Formula 1, R1 may be a phenylene group which is an arylene group having 6 to 20 carbon atoms, and R2 may be a butylene group which is an alkylene group having 1 to 10 carbon atoms.

[0044] The polyether-based repeating unit may include a reaction product of a dicarboxylic acid or a derivative thereof and a polyether diol. Examples of the dicarboxylic acid or a derivative thereof include terephthalic acid, which is an aromatic dicarboxylic acid, and examples of the polyether diol include poly(tetramethylene ether) glycol.

[0045] The polyester repeating unit means a repeating unit containing a polyester functional group in the repeating unit structure, and specifically may have a structure represented by the following Chemical Formula 2.

[0046] [ka]

[0047] In the above chemical formula 2, R3 is one of an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 3 to 10 carbon atoms, or an arylene group having 6 to 20 carbon atoms, and R4 is an alkylene group having 1 to 10 carbon atoms.

[0048] As a more specific example, in the above chemical formula 2, R3 may be a phenylene group which is an arylene group having 6 to 20 carbon atoms, and R4 may be a butylene group which is an alkylene group having 1 to 10 carbon atoms.

[0049] The polyester repeating unit may include a reaction product of a dicarboxylic acid or a derivative thereof and a diol. Examples of the dicarboxylic acid or a derivative thereof include terephthalic acid, which is an aromatic dicarboxylic acid, and examples of the diol include 1,4-butanediol, which is an aliphatic diol.

[0050] The polyether repeating units may constitute soft segments that provide elasticity and flexibility in the polyetherester copolymer, and the polyester repeating units may constitute hard segments that provide mechanical properties in the polyetherester copolymer.

[0051] That is, the polyether ester contains both the polyether repeating units and the polyester repeating units, and thus has hard segments and soft segments and exhibits the properties of an elastomer.

[0052] Meanwhile, the polyetherester copolymer may contain monometallic salts of inorganic acids and multimetallic salts of inorganic acids remaining in the polymer matrix. The monometallic salts of inorganic acids and multimetallic salts of inorganic acids can be added as co-catalysts along with the diol, dicarboxylic acid or its derivative, and polyetherdiol monomers and the main catalyst during the synthesis of the polyetherester copolymer, and some or all of them can remain in the final synthesized polyetherester copolymer.

[0053] This can be confirmed by inductively coupled plasma (ICP) analysis of the final synthesized polyetherester copolymer. Specifically, the presence of two inorganic acid metal salt cocatalysts remaining in the polyetherester copolymer can be confirmed by quantitative analysis of metal elements (e.g., Na and S) using ICP. Additionally, the content and ratio of the two inorganic acid metal salt cocatalysts can be confirmed by ion chromatography analysis or a combination of ICP and ion chromatography.

[0054] The multimetal salt of an inorganic acid refers to a salt obtained by an acid-base neutralization reaction between a base compound containing a metal component and an inorganic acid, and particularly refers to a salt compound containing two or more metal components in the final salt compound. In other words, if the number of metal components in the chemical formula of a metal salt of an inorganic acid is two or more, it is defined as a multimetal salt of an inorganic acid.

[0055] The multi-metal salt of an inorganic acid may include a di-metal salt of an inorganic acid, a tri-metal salt of an inorganic acid, a tetra-metal salt of an inorganic acid, or a penta-metal salt of an inorganic acid, depending on the number of metal components.

[0056] Examples of dimetal salts of inorganic acids among the multiple metal salts of inorganic acids include sodium sulfate (Na2SO4), disodium hydrogen phosphate (Na2HPO4), and trisodium phosphate (Na3PO4).

[0057] The inorganic acid multimetal salt acts as a co-catalyst during the synthesis of the polyetherester copolymer, thereby shortening the polymerization time of the polyetherester copolymer.

[0058] The monometallic salt of an inorganic acid refers to a salt obtained by an acid-base neutralization reaction between a base compound containing a metal component and an inorganic acid, particularly when the final salt compound contains a single metal component. In other words, if the chemical formula of a metal salt of an inorganic acid contains a single metal component, it is defined as a monometallic salt of an inorganic acid. Examples of monometallic salts of inorganic acids include sodium bisulfate (NaHSO4) and sodium dihydrogen phosphate (NaH2PO4).

[0059] The monometallic salt of an inorganic acid acts as a co-catalyst during the synthesis of the polyetherester copolymer, helping to shorten the polymerization time of the polyetherester copolymer by the multimetallic salt of an inorganic acid. This allows the polymerization time to be sufficiently shortened even with a smaller amount of the multimetallic salt of an inorganic acid, thereby improving process efficiency.

[0060] Therefore, when a mixture of a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid is used, a sufficient polymerization time reduction effect can be achieved with a smaller amount of the inorganic multimetallic salt due to the monometallic salt of the inorganic acid. In contrast, when only one monometallic salt of an inorganic acid is used, the polymerization time of the polyetherester copolymer increases to more than 140 minutes, which is a problem in that the polymerization time is not reduced sufficiently. When only one multimetallic salt of an inorganic acid is used, an excess of the inorganic multimetallic salt must be added to reduce the polymerization time sufficiently, which is a problem in that it is difficult to ensure process efficiency.

[0061] Specifically, the weight ratio of the multi-metal salt of an inorganic acid to 1 part by weight of the mono-metal salt of an inorganic acid may be 10 parts by weight or more, or 20 parts by weight or more, or 50 parts by weight or more, or 100 parts by weight or more, or 1000 parts by weight or less, or 200 parts by weight or less, or 10 parts by weight to 1000 parts by weight, or 20 parts by weight to 1000 parts by weight, or 50 parts by weight to 1000 parts by weight, or 100 parts by weight to 1000 parts by weight, or 10 parts by weight to 200 parts by weight, or 20 parts by weight to 200 parts by weight, or 50 parts by weight to 200 parts by weight, or 100 parts by weight to 200 parts by weight.

[0062] If the weight ratio of the inorganic acid multimetal salt to 1 part by weight of the inorganic acid monometal salt is too low, such as less than 10 parts by weight, the effect of shortening the polymerization time of the polyetherester copolymer by the inorganic acid multimetal salt is difficult to fully achieve.If the weight ratio of the inorganic acid multimetal salt to 1 part by weight of the inorganic acid monometal salt is too high, such as more than 1,000 parts by weight, an excess of the inorganic acid multimetal salt must be added, which makes it difficult to ensure process efficiency.

[0063] More specifically, the inorganic acid multiple metal salt is contained in an amount of 10 ppm to 10,000 ppm, or 10 ppm to 5,000 ppm, or 10 ppm to 4,000 ppm, or 100 ppm to 10,000 ppm, or 100 ppm to 5,000 ppm, or 100 ppm to 4,000 ppm, or 500 ppm to 10,000 ppm, or 500 ppm to 5,000 ppm, or 500 ppm to 4,000 ppm, or 1,000 ppm to 10,000 ppm, or 1,000 ppm to 5,000 ppm, or 1,000 ppm to 4,000 ppm.

[0064] The inorganic acid monometal salt is contained in a content of 0.1 ppm to 150 ppm, or 0.1 ppm to 100 ppm, or 0.1 ppm to 80 ppm, or 0.1 ppm to 50 ppm, or 1 ppm to 150 ppm, or 1 ppm to 100 ppm, or 1 ppm to 80 ppm, or 1 ppm to 50 ppm, or 10 ppm to 150 ppm, or 10 ppm to 100 ppm, or 10 ppm to 80 ppm, or 10 ppm to 50 ppm, based on the weight of the polyetherester copolymer.

[0065] The inorganic acid may include a polyvalent inorganic acid. The polyvalent inorganic acid is a polyprotic acid that can release more than one hydrogen ion among inorganic acids, and may include divalent inorganic acids, trivalent inorganic acids, tetravalent inorganic acids, pentavalent inorganic acids, etc. depending on the number of hydrogen ions. More specifically, examples of the inorganic acid include sulfuric acid and phosphoric acid.

[0066] The metal may include an alkali metal or an alkaline earth metal, and specific examples of the metal include sodium, potassium, calcium, magnesium, or a mixture thereof.

[0067] The polyetherester copolymer may have a yellowness index (YI) measured using a color meter of 24 or less, or 23 or less, or 22 or less, or 1 or more, or 1 to 24, or 1 to 23, or 1 to 22. If the yellowness index of the polyetherester copolymer measured using a color meter is excessively increased to exceed 24, there is a problem that it is difficult to ensure a high level of transparency due to excessive yellowing.

[0068] The polyetherester copolymer has a melting point (T m) may be 150°C or higher, or 200°C or higher, or 201°C or higher, or 202°C or higher, or 203°C or higher, or 250°C or lower, or 210°C or lower, or 150°C to 250°C, or 200°C to 250°C, or 201°C to 250°C, or 202°C to 250°C, or 203°C to 250°C, or 200°C to 210°C, or 201°C to 210°C, or 202°C to 210°C, or 203°C to 210°C. An example of a differential scanning calorimeter for measuring the melting point is a Differential Scanning Calorimetry (Device name: DSC2920, Manufacturer: TA Instrument). The melting point can be determined from a temperature-heat flow graph obtained by scanning in a temperature range of 0°C to 250°C at a heating rate or cooling rate of 5°C / min to 15°C / min. More specifically, the melting point (T m ) was obtained by peak analysis of the heat flow heating curve during the second temperature rise.

[0069] The polyetherester copolymer has a melting point (T m If the temperature is too low below 150°C, the efficiency of the molding process for the polyether ester copolymer may decrease.

[0070] The polyether ester copolymer may have a crystallization temperature measured by a differential scanning calorimeter of 70°C or higher, or 151°C or higher, or 152°C or higher, or 153°C or higher, or 154°C or higher, or 155°C or higher, or 156°C or higher, or 200°C or lower, or 160°C or lower, or 70°C to 200°C, or 151°C to 200°C, or 152°C to 200°C, or 153°C to 200°C, or 154°C to 200°C, or 155°C to 200°C, or 156°C to 200°C, or 70°C to 160°C, or 151°C to 160°C, or 152°C to 160°C, or 153°C to 160°C, or 154°C to 160°C, or 155°C to 160°C, or 156°C to 160°C. An example of a differential scanning calorimeter for measuring the crystallization temperature is a Differential Scanning Calorimetry, device name: DSC2920, manufactured by TA Instrument. The crystallization temperature can be determined from a temperature-heat flow graph obtained by scanning at a heating rate of 5°C / min to 15°C / min in a temperature range of 0°C to 250°C or at a cooling rate of 5°C / min to 15°C / min. More specifically, the crystallization temperature (T c ) is determined by peak analysis of the cooling curve of the heat flow during the first cooling.

[0071] If the crystallization temperature of the polyetherester copolymer measured by a differential scanning calorimeter is too low, below 70° C., the efficiency of the molding process for the polyetherester copolymer may decrease.

[0072] The polyetherester copolymer may have a melt index of 30 g / 10 min or less, or 29 g / 10 min or less, or 28 g / 10 min or less, or 27 g / 10 min or less, or 26 g / 10 min or less, or 10 g / 10 min or more, or 10 g / 10 min to 30 g / 10 min, or 10 g / 10 min to 29 g / 10 min, or 10 g / 10 min to 28 g / 10 min, or 10 g / 10 min to 27 g / 10 min, or 10 g / 10 min to 26 g / 10 min, as measured according to ASTM D1238 at 230°C under a load of 2.16 kg for 4 minutes. The melt index is measured using a dried sample of the polyetherester copolymer in the same manner as ASTM D1238 (230°C under a load of 2.16 kg for 4 minutes). The drying conditions for the polyetherester copolymer are not particularly limited, but for example, drying can be carried out at a temperature of 50° C. or higher and 100° C. or lower for 6 hours or longer.

[0073] The applications of the polyether ester copolymer are not particularly limited, and it can be used in any of the application fields of conventionally known thermoplastic polyester elastomers (TPEEs) without any restrictions, but for example, it can be used in a variety of applications such as automobile parts, automobile interior materials, automobile exterior materials, cables, wires, hoses, tubes, antenna covers, leisure goods, and sporting goods.

[0074] There is no limitation on the molding process for such applications, and various conventionally known molding processes for thermoplastic polyester elastomers (TPEEs) can be applied without limitation.

[0075] 2. Method for producing polyetherester copolymer According to another embodiment of the present invention, there is provided a method for producing a polyether ester copolymer, comprising: a) an esterification reaction step of reacting a diol, a dicarboxylic acid or a derivative thereof, and a polyether diol in the presence of a catalyst and a co-catalyst; b) a first condensation polymerization step of adding a catalyst to the reaction mixture obtained after the completion of step a) and carrying out condensation polymerization under reduced pressure to produce a prepolymer; and c) a second condensation polymerization step of condensing the prepolymer under a pressure condition lower than that of step b); wherein the co-catalyst comprises a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid.

[0076] Specifically, the method for producing the polyetherester copolymer may include a) an esterification reaction step of reacting a diol, a dicarboxylic acid or a derivative thereof, and a polyetherdiol in the presence of a catalyst and a cocatalyst.

[0077] In the present invention, the diol is preferably an aliphatic or alicyclic diol having 2 to 10 carbon atoms and a molecular weight of 300 g / mol or less, in terms of achieving the effects of the present invention. Specific examples of diols that can be used in the present invention include, but are not limited to, aliphatic diols such as 1,4-butylene glycol (1,4-butanediol), monoethylene glycol, diethylene glycol, propylene glycol, and neopentyl glycol; and alicyclic diols such as 1,1-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, and tricyclodecanedimethanol. Specifically, in the present invention, the diol may be 1,4-butanediol, which is an aliphatic diol.

[0078] Examples of dicarboxylic acids that can be used in the present invention include, but are not limited to, terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, adipic acid, and sebacic acid. Specifically, the dicarboxylic acid may be terephthalic acid. Examples of dicarboxylic acid derivatives that can be used in the present invention include, but are not limited to, dialkyl terephthalate, dialkyl isophthalate, dialkyl naphthalenedicarboxylate, dialkyl adipate, and dialkyl sebacate. Specifically, the dicarboxylic acid or its derivative may be dimethyl terephthalate, which is a derivative of an aromatic dicarboxylic acid.

[0079] The polyether diol usable in the present invention may be in the form of a homopolymer or copolymer, and specific examples include, but are not limited to, one or more selected from the group consisting of polytetramethylene glycol, polyethylene glycol, polypropylene glycol, polyethylene glycol-polypropylene glycol-polyethylene glycol, and polyhexamethylene glycol. Specifically, the polyether diol may be polytetramethylene glycol.

[0080] The number average molecular weight (Mn) of the polyether diol is not particularly limited, but may be from 500 g / mol to 3000 g / mol, or from 500 g / mol to 2000 g / mol, or from 500 g / mol to 1500 g / mol. The number average molecular weight can be determined, for example, by gel permeation chromatography (GPC), an end titration method (a method comprising acetylating the ends of a polyether diol using acetic anhydride, decomposing unreacted acetic anhydride into acetic acid, measuring the OH value of the acetylated polyether diol by back titration with an alkali, and determining the number average molecular weight of the polyether diol from the OH value), or an -OH end group analysis method using H NMR analysis.

[0081] The esterification reaction of the diol, dicarboxylic acid or its derivative, and polyether diol is carried out in the presence of a catalyst (main catalyst) and a co-catalyst. The catalyst (main catalyst) can be any suitable catalyst known in the art. Specifically, the catalyst (main catalyst) can be a catalyst containing titanium or tin as an active metal. More specifically, the catalyst can be a titanium-based catalyst such as tetrabutyl titanate (TBT), tetraethyl titanate, or tetra(isopropyl)titanate; or a tin-based catalyst such as n-butylstannoic acid, octylstannoic acid, dimethyltin oxide, dibutyltin oxide, dioctyltin oxide, diphenyltin oxide, tri-n-butyltin acetate, tri-n-butyltin chloride, or tri-n-butyltin fluoride. In addition to the above-mentioned catalysts, oxides or acetates containing Mg, Ca, Mn, Zn, Pb, Zr, or the like as active metals can be used alone or in combination. Of these, titanium-based catalysts such as TBT are preferably used.

[0082] Meanwhile, in the present invention, the catalyst is added not only in the esterification reaction but also in the polycondensation step. Generally, when producing a polyetherester copolymer, the catalyst for the esterification (or transesterification) reaction and the polycondensation reaction is the same, and no separation step is required between the two reactions. Therefore, after adding a certain amount of catalyst at the start or during the initial esterification (or transesterification) reaction, it is not necessary to add additional catalyst in the polycondensation step.

[0083] The co-catalyst can include monometallic salts of inorganic acids and dimetallic salts of inorganic acids. The multimetallic salts of inorganic acids refer to salts obtained by the acid-base neutralization reaction between a base compound containing a metal component and an inorganic acid, and particularly refer to salts containing two or more metal components in the final salt compound. In other words, if the number of metal components in the chemical formula of a metal salt of an inorganic acid is two or more, it is defined as a multimetallic salt of an inorganic acid.

[0084] The multi-metal salt of an inorganic acid may include a di-metal salt of an inorganic acid, a tri-metal salt of an inorganic acid, a tetra-metal salt of an inorganic acid, or a penta-metal salt of an inorganic acid, depending on the number of metal components.

[0085] Examples of dimetal salts of inorganic acids among the multiple metal salts of inorganic acids include sodium sulfate (Na2SO4), disodium hydrogen phosphate (Na2HPO4), and trisodium phosphate (Na3PO4).

[0086] The inorganic acid multimetal salt acts as a co-catalyst during the synthesis of the polyetherester copolymer, thereby shortening the polymerization time of the polyetherester copolymer.

[0087] The monometallic salt of an inorganic acid refers to a salt obtained by an acid-base neutralization reaction between a base compound containing a metal component and an inorganic acid, particularly when the final salt compound contains a single metal component. In other words, if the chemical formula of a metal salt of an inorganic acid contains a single metal component, it is defined as a monometallic salt of an inorganic acid. Examples of monometallic salts of inorganic acids include sodium bisulfate (NaHSO4) and sodium dihydrogen phosphate (NaH2PO4).

[0088] The monometallic salt of an inorganic acid acts as a co-catalyst during the synthesis of the polyetherester copolymer, helping to shorten the polymerization time of the polyetherester copolymer by the multimetallic salt of an inorganic acid. This allows the polymerization time to be sufficiently shortened even with a smaller amount of the multimetallic salt of an inorganic acid, thereby improving process efficiency.

[0089] Therefore, when a mixture of a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid is used, a sufficient polymerization time reduction effect can be achieved with a smaller amount of the inorganic multimetallic salt due to the monometallic salt of the inorganic acid. In contrast, when only one monometallic salt of an inorganic acid is used, the polymerization time of the polyetherester copolymer increases to more than 140 minutes, which is a problem in that the polymerization time is not reduced sufficiently. When only one multimetallic salt of an inorganic acid is used, an excess of the inorganic multimetallic salt must be added to reduce the polymerization time sufficiently, which is a problem in that it is difficult to ensure process efficiency.

[0090] Specifically, the weight ratio of the multi-metal salt of an inorganic acid to 1 part by weight of the mono-metal salt of an inorganic acid may be 10 parts by weight or more, or 20 parts by weight or more, or 50 parts by weight or more, or 100 parts by weight or more, or 1000 parts by weight or less, or 200 parts by weight or less, or 10 parts by weight to 1000 parts by weight, or 20 parts by weight to 1000 parts by weight, or 50 parts by weight to 1000 parts by weight, or 100 parts by weight to 1000 parts by weight, or 10 parts by weight to 200 parts by weight, or 20 parts by weight to 200 parts by weight, or 50 parts by weight to 200 parts by weight, or 100 parts by weight to 200 parts by weight.

[0091] If the weight ratio of the inorganic acid multimetal salt to 1 part by weight of the inorganic acid monometal salt is too low, such as less than 10 parts by weight, the effect of shortening the polymerization time of the polyetherester copolymer by the inorganic acid multimetal salt is difficult to fully achieve.If the weight ratio of the inorganic acid multimetal salt to 1 part by weight of the inorganic acid monometal salt is too high, such as more than 1,000 parts by weight, an excess of the inorganic acid multimetal salt must be added, which makes it difficult to ensure process efficiency.

[0092] More specifically, the inorganic acid multiple metal salt is contained in a content of 10 ppm to 10,000 ppm, or 10 ppm to 5,000 ppm, or 10 ppm to 4,000 ppm, or 100 ppm to 10,000 ppm, or 100 ppm to 5,000 ppm, or 100 ppm to 4,000 ppm, or 500 ppm to 10,000 ppm, or 500 ppm to 5,000 ppm, or 500 ppm to 4,000 ppm, or 1,000 ppm to 10,000 ppm, or 1,000 ppm to 5,000 ppm, or 1,000 ppm to 4,000 ppm.

[0093] The monometal salt of an inorganic acid may be present in an amount of 0.1 ppm to 150 ppm, or 0.1 ppm to 100 ppm, or 0.1 ppm to 80 ppm, or 0.1 ppm to 50 ppm, or 1 ppm to 150 ppm, or 1 ppm to 100 ppm, or 1 ppm to 80 ppm, or 1 ppm to 50 ppm, or 10 ppm to 150 ppm, or 10 ppm to 100 ppm, or 10 ppm to 80 ppm, or 10 ppm to 50 ppm, based on the weight of the reaction mixture after step a).

[0094] The inorganic acid may include a polyvalent inorganic acid. The polyvalent inorganic acid is a polyprotic acid that can release more than one hydrogen ion among inorganic acids, and may include divalent inorganic acids, trivalent inorganic acids, tetravalent inorganic acids, pentavalent inorganic acids, etc. depending on the number of hydrogen ions. More specifically, examples of the inorganic acid include sulfuric acid and phosphoric acid.

[0095] The metal may include an alkali metal or an alkaline earth metal, and specific examples of the metal include sodium, potassium, calcium, magnesium, or a mixture thereof. Meanwhile, in the present invention, a certain amount of the co-catalyst may be added at the start of the initial esterification (or transesterification) reaction, at the initial stage of the reaction, or at the final stage of the reaction, and may also be added additionally in the polycondensation step, if necessary.

[0096] The reaction temperature in step a) is suitably in the range of 150°C to 300°C or 200°C to 240°C, and the reaction pressure may be in the range of 100 torr to 760 torr. Specifically, the starting materials and the catalyst are charged into a reactor, and the temperature is increased at a rate of 0.1°C / min to 10°C / min with stirring until the temperature reaches the above range, and the esterification reaction can be carried out for about 30 minutes to 4 hours, or 1 to 2 hours.

[0097] After step a) is completed, the polycondensation steps b) and c) are carried out. The polycondensation step is carried out in a reactor separate from the esterification reactor and may be carried out without a distillation column. Specifically, the polycondensation step is carried out after adding an active metal-based catalyst of 50 ppm or more to the reaction mixture after step a) is completed.

[0098] In the present invention, the polycondensation step is divided into two steps, b) and c). Steps b) and c) are carried out substantially continuously, but differ in pressure conditions. Specifically, step b) is a process for removing excess diol, and step c) is a process for increasing the viscosity of the polyetherester copolymer.

[0099] Specifically, the method for preparing the polyetherester copolymer may include a first condensation polymerization step of preparing a prepolymer by adding a catalyst to the reaction mixture obtained by the step a) and condensing the mixture under reduced pressure.

[0100] Step b) of the present invention is a first polycondensation step carried out under relatively mild conditions, in which a catalyst is additionally added to the reaction mixture after step a), and the mixture is stirred under reduced pressure to carry out polycondensation to obtain a prepolymer.

[0101] Step b) is carried out at a temperature of 180°C to 250°C and a pressure of 5 to 100 torr. Under these conditions, the excess diol that has not reacted in step a) is vaporized and removed. The reaction time for step b) is not particularly limited, but may be 20 minutes to 1 hour, or 20 minutes to 40 minutes.

[0102] If the polycondensation is carried out immediately under a high vacuum of 5 torr or less without carrying out step b), the unreacted diol may be rapidly vaporized, causing bumping in the reactor and a significant drop in the temperature of the reactants. Furthermore, the polyetherester copolymer may have a high viscosity and may not be obtained. Therefore, in the present invention, a preliminary first polycondensation step is carried out under relaxed conditions before the full polycondensation reaction.

[0103] Meanwhile, in step a) or b), one or more commonly used additives may be added to improve the reaction efficiency and adjust the physical properties of the polyetherester copolymer to be produced.

[0104] Examples of additives that can be used include, but are not limited to, branching agents (e.g., glycerol, sorbitol, pentaerythritol, 1,1,4,4-tetrakis(hydroxymethyl)cyclohexane, trimethylolpropane, pyromellitic acid, 1,1,2,2-ethanetetracarboxylic acid, etc.) to increase the melt strength of the polyetherester copolymer, photoabsorbers (e.g., TiO, zinc sulfide, or zinc oxide) to improve color properties, colorants (e.g., dyes), stabilizers (e.g., antioxidants, ultraviolet light stabilizers, heat stabilizers, etc.), fillers, flame retardants, pigments, antimicrobial agents, antistatic agents, optical brighteners, extenders, processing aids, or viscosity enhancers, any one or mixtures of two or more of these. For example, a stabilizer in the form of a hindered phenol (e.g., Irganox 1330) can be incorporated to enhance the thermal stability of the polyetherester copolymer.

[0105] These additives can be used in an appropriate content within a range that ensures the intended effect and does not deteriorate the physical properties of the polyetherester copolymer produced; specifically, they can be used in an amount of 0.1 to 10% by weight relative to 100% by weight of the total raw materials.

[0106] The method for preparing the polyetherester copolymer may also include a second polycondensation step of polycondensing the prepolymer under a pressure condition lower than that of steps c) and b).

[0107] Step c) is a reaction subsequent to step b), in which the prepolymer is polycondensed in the same reactor, only at a lower pressure.

[0108] In step c), the time from the start of the reaction to the point at which the torque value attached to the mechanical stirrer reaches 0.8 Nm and the reaction is terminated may be 100 minutes or less, or 95 minutes or less, or 94 minutes or less, or 90 minutes or less, or 50 minutes or more, or 50 to 100 minutes, or 50 to 95 minutes, or 50 to 94 minutes, or 50 to 90 minutes. If the time from the start of the reaction to the point at which the torque value attached to the mechanical stirrer reaches 0.8 Nm and the reaction is terminated is excessively long, the polymerization time may not be sufficiently shortened, resulting in a problem of reduced productivity.

[0109] Step c) is carried out at a temperature of 180°C to 250°C and a pressure of 5 torr or less. Polycondensation is carried out under these conditions for about 30 minutes to 5 hours, or 1 to 3 hours, and the reaction is completed when the torque value reaches a range of 0.5 Nm to 2.0 Nm, finally producing a polyetherester copolymer. [Effects of the Invention]

[0110] According to the present invention, there are provided a polyetherester copolymer which maintains excellent physical properties of the copolymer and can significantly reduce the polymerization time to increase productivity, and a method for producing the same. DETAILED DESCRIPTION OF THE INVENTION

[0111] The present invention will be described in more detail in the following examples, but the following examples are merely illustrative of the present invention and are not intended to limit the scope of the present invention.

[0112] <Examples, Comparative Examples, and Reference Examples: Production of Polyetherester Copolymer> Example 1 A 2-L glass reactor was charged with 120 g of terephthalic acid, 200 g of 1,4-butanediol, and poly(tetramethylene ether) glycol (PTMG, Mn=1,000). g / mol 80g of tetrabutyl titanate (TBT) catalyst 50ppm (Ti element basis), sodium sulfate (Na2SO4) 800ppm (based on total raw material input) and sodium bisulfate (NaHSO4) 30ppm (based on total raw material input) as co-catalysts were added, and the mixture was stirred under nitrogen for 2 hours at 230°C, and the temperature was increased and the esterification (ES) reaction was carried out at a pressure of 100 to 760 torr.

[0113] After the ES reaction, 50 ppm (Ti element basis) of tetrabutyl titanate (TBT) catalyst and 3000 ppm of Irganox 1330 as an antioxidant were added to the reactor, followed by stirring for 10 minutes. After removing the liquid by-products generated in the Dean-Stark trap, the pressure was reduced to 10 torr at a temperature of 230°C for 30 minutes, and the first polycondensation (PP) reaction was carried out.

[0114] The second polycondensation (PC) reaction was then carried out at 240°C and 1 torr or less. During the PC reaction, the torque attached to the mechanical stirrer continuously increased, and when the torque reached 0.8 Nm, the reaction was stopped, pressurized, and discharged into cold water. The product was cooled and dried to obtain a PBT-PTMG copolymer.

[0115] (Examples 2-3, Comparative Examples 1-4, Reference Examples 1-2) As shown in Table 1 below, a PBT-PTMG copolymer was obtained in the same manner as in Example 1, except that the contents of the co-catalysts sodium sulfate (NaSO) 800 ppm (based on the total amount of raw materials) and sodium bisulfate (NaHSO) 30 ppm (based on the total amount of raw materials) were changed.

[0116] <Experimental example: Measurement of physical properties of polyether ester copolymer> The physical properties of the polyether ester copolymers obtained in the above examples and comparative examples were measured by the following methods, and the results are shown in Table 1.

[0117] 1. Secondary Polycondensation (PC) Reaction Time (unit: minutes) In the examples and comparative examples, the time from the start of the second polycondensation (PC) reaction to the time when the torque value attached to the mechanical stirrer reached 0.8 Nm and the reaction was stopped was measured.

[0118] 2. Melting index (unit: g / 10 min) The polyetherester copolymers obtained in the examples and comparative examples were vacuum dried in an oven at 60°C for 6 hours or more, and the melt index of each sample was measured in the same manner as ASTM D1238 (230°C, 2.16 kg load, 4 minutes).

[0119] 3. Melting point, crystallization temperature (unit: °C) The polyether ester copolymers obtained in the examples and comparative examples were scanned twice using a differential scanning calorimeter (DSC2920, manufactured by TA Instrument) in the temperature range of 0°C to 250°C at a heating rate or cooling rate of 10°C / min. The melting points (T m ) and crystallization temperature (T c ) was measured.

[0120] The crystallization temperature (T c ) is obtained by peak analysis of the cooling curve of the heat flow during the first cooling stage, and the melting point (T m ) was obtained by peak analysis of the heat flow heating curve during the second temperature rise.

[0121] 4.Yellow index The polyetherester copolymers obtained in the above examples and comparative examples were measured using a color meter ZE6000 (NIPPON DENSHOKU).

[0122] [Table 1]

[0123] As shown in Table 1, the polyetherester copolymers of Examples 1 to 3 exhibited the same levels of melt index, melting point, crystallization temperature, and yellow index properties as the Comparative Examples and Reference Examples, but had PC reaction times of 87 to 95 minutes, which were shorter than those of Comparative Examples 1, 2, 3, and 4 and Reference Examples 1 and 2, which had PC reaction times of 100 minutes or more, thereby improving process efficiency.

Claims

1. a polymeric matrix comprising polyether-based repeating units and polyester-based repeating units; and monometallic salts of inorganic acids and multimetallic salts of inorganic acids that remain in the polymer matrix; A polyetherester copolymer, wherein the weight ratio of the multimetal salt of an inorganic acid to 1 part by weight of the monometal salt of an inorganic acid is 10 parts by weight or more.

2. 2. The polyetherester copolymer according to claim 1, wherein the polyetherester copolymer has a yellowness index of 24 or less as measured using a color meter.

3. The polyetherester copolymer according to claim 1, wherein the polyetherester copolymer has a melting point of 150°C or higher as measured by a differential scanning calorimeter.

4. The polyetherester copolymer according to claim 1, wherein the polyetherester copolymer has a crystallization temperature of 70°C or higher as measured by a differential scanning calorimeter.

5. The polyetherester copolymer of claim 1 , wherein the inorganic acid comprises sulfuric acid or phosphoric acid.

6. 2. The polyetherester copolymer of claim 1, wherein the metal of the monometallic salt of an inorganic acid or the metal of the multimetallic salt of an inorganic acid comprises an alkali metal or an alkaline earth metal.

7. the multimetal salt of an inorganic acid is sodium sulfate; 2. The polyetherester copolymer of claim 1, wherein the monometallic salt of an inorganic acid is sodium hydrogen sulfate.

8. 2. The polyetherester copolymer according to claim 1, wherein the multimetal salt of an inorganic acid is contained in an amount of 10 ppm to 10,000 ppm based on the weight of the polyetherester copolymer.

9. 2. The polyetherester copolymer according to claim 1, wherein the monometallic salt of an inorganic acid is contained in an amount of 0.1 ppm to 150 ppm based on the weight of the polyetherester copolymer.

10. The polyether ester copolymer according to claim 1, wherein the polyether repeating unit has a structure represented by the following chemical formula 1: 【Chemical 1】 In the above Chemical Formula 1, R 1 is one of an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 3 to 10 carbon atoms, or an arylene group having 6 to 20 carbon atoms, R 2 is an alkylene group having 1 to 10 carbon atoms, n is an integer from 1 to 100.

11. The polyetherester copolymer according to claim 1, wherein the polyester repeating unit has a structure represented by the following chemical formula 2: 【Chemistry 2】 In the above Chemical Formula 2, R 3 is one of an alkylene group having 1 to 10 carbon atoms, a cycloalkylene group having 3 to 10 carbon atoms, or an arylene group having 6 to 20 carbon atoms, R 4 is an alkylene group having 1 to 10 carbon atoms.

12. a) an esterification reaction step in which a diol, a dicarboxylic acid or a derivative thereof, and a polyether diol are reacted in the presence of a catalyst and a cocatalyst; b) a first polycondensation step in which a catalyst is added to the reaction mixture obtained after the step a) and polycondensed under reduced pressure to prepare a prepolymer; and c) a second polycondensation step in which the prepolymer is polycondensed under a pressure condition lower than that in step b); The co-catalyst comprises a monometallic salt of an inorganic acid and a multimetallic salt of an inorganic acid.

13. 13. The method for producing a polyetherester copolymer according to claim 12, wherein in step c), the time from the start of the reaction to the time when the torque value attached to a mechanical stirrer reaches 0.8 Nm and the reaction is terminated is 100 minutes or less.

14. The method for producing a polyetherester copolymer according to claim 12, wherein the weight ratio of the multimetal salt of an inorganic acid to 1 part by weight of the monometal salt of an inorganic acid is 10 parts by weight or more.

15. The method for producing a polyetherester copolymer according to claim 12, wherein the inorganic acid multimetal salt is added in an amount of 10 ppm to 10,000 ppm based on the weight of the reaction mixture after step a).

16. The method for producing a polyetherester copolymer according to claim 12, wherein the monometallic salt of an inorganic acid is added in an amount of 0.1 ppm to 150 ppm based on the weight of the reaction mixture after step a) is completed.

17. the multimetal salt of an inorganic acid is sodium sulfate; The method for producing a polyetherester copolymer according to claim 12, wherein the monometallic salt of an inorganic acid is sodium hydrogen sulfate.

18. 13. The method for producing a polyetherester copolymer according to claim 12, wherein step b) is carried out at a temperature of 180°C to 250°C and a pressure of 0.67 kPa to 13.33 kPa (5 torr to 100 torr).

19. The method for producing a polyetherester copolymer according to claim 12, wherein step c) is carried out at a temperature of 180°C to 250°C and a pressure of 0.67 kPa (5 torr or less).

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