Patent Application
20250136753
The present disclosure relates to a polyester polymer that can significantly shorten a polymerization time and increase productivity, while maintaining a state of excellence in physical properties, a method for preparing the same, and a catalyst system.
Polyester polymers are commercially prepared by a two-step reaction including performing an esterification or an ester exchange reaction using a diol, a dicarboxylate and a polyether diol as starting materials, and then performing a polycondensation reaction of the reaction product.
As an example, polybutylene terephthalate (PBT), which is one of the well-known polyester polymers, is prepared through an esterification and a polycondensation reaction using 1,4-butylene glycol (BG), and terephthalic acid (TPA) as starting materials.
Meanwhile, in the polycondensation step, a cocatalyst can be additionally applied in addition to the main catalyst to improve productivity, and alkali metallic salts or alkaline earth metallic salts such as Na-acetate, Mg acetate, and Ca acetate have been mainly used as such cocatalysts.
However, in processes using existing cocatalysts, there was an aspect unsuitable for mass production because it is difficult to sufficiently shorten the polymerization time and the productivity is still low.
Therefore, there is a need to provide a method for preparing a polyester polymer that can sufficiently shorten the polymerization time so as to be suitable for mass production, while preparing a polyester polymer maintaining thermal and mechanical properties of a level equivalent to conventional ones.
The background description provided herein is for the purpose of generally presenting context of the disclosure. Unless otherwise indicated herein, the materials described in this section are not prior art to the claims in this application and are not admitted to be prior art, or suggestions of the prior art, by inclusion in this section.
It is an object of the present disclosure to provide a polyester polymer that can significantly shorten a polymerization time and increase productivity, while maintaining a state of excellence in physical properties.
It is another object of the present disclosure to provide a method for preparing the polyester polymer.
It is yet another object of the present disclosure to provide a catalyst system used in the preparation of the polyester polymer.
In order to achieve the above object, provided herein is a polyester polymer comprising: a polymer matrix containing a polyester repeating unit; and a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid that remain in the polymer matrix.
Also provided herein is a method for preparing a polyester polymer, comprising the steps of: a) an esterification reaction step of reacting a diol, and a dicarboxylic acid or a derivative thereof in the presence of a catalyst and a cocatalyst to obtain a reaction mixture; b) a first polycondensation step of introducing the catalyst to the reaction mixture in which the step a) is completed and performing polycondensation under reduced pressure to prepare a prepolymer; and c) a second polycondensation step of performing polycondensation of the prepolymer under a pressure condition lower than that of the step b), wherein the cocatalyst includes a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid.
Further provided herein is a catalyst system comprising a catalyst and a cocatalyst, wherein the cocatalyst includes a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid.
Now, a polyester polymer, a method for preparing the same and a catalyst system according to specific embodiments of the present disclosure will be described in more detail.
Unless explicitly stated herein, the technical terms used herein are for the purpose of describing specific embodiments only and is not intended to limit the scope of the invention.
The singular forms “a,” “an” and “the” used herein are intended to include plural forms, unless the context clearly indicates otherwise.
It should be understood that the terms “comprise,” “include”, “have”, etc. are used herein to specify the presence of stated feature, region, integer, step, action, element and/or component, but do not preclude the presence or addition of one or more other feature, region, integer, step, action, element, component and/or group.
Further, the terms including ordinal numbers such as “a first”, “a second”, etc. are used only for the purpose of distinguishing one component from another component, and are not limited by the ordinal numbers. For instance, a first component may be referred to as a second component, or similarly, the second component may be referred to as the first component, without departing from the scope of the present disclosure.
In the present disclosure, examples of the substituent groups are described below, but is not limited thereto.
As used herein, the term “substituted” means that another functional group bonds instead of a hydrogen atom in the compound, and a position to be substituted is not limited as long as it is a position at which the hydrogen atom is substituted, namely, a position at which it is substitutable with the substituent. When two or more substituents are substituted, the two or more substituents may be identical to or different from each other.
As used herein, the term “substituted or unsubstituted” means being unsubstituted or substituted with one or more substituents selected from the group consisting of deuterium; a halogen group; a cyano group; a nitro group; a hydroxy group; a carbonyl group; an ester group; an imide group; an amide group; a primary amino group; a carboxy group; a sulfonic acid group; a sulfonamide group; a phosphine oxide group; an alkoxy group; an aryloxy group; an alkylthioxy group; an arylthioxy group; an alkylsulfoxy group; an arylsulfoxy group; a silyl group; a boron group; an alkyl group; a cycloalkyl group; an alkenyl group; an aryl group; an aralkyl group; an aralkenyl group; an alkylaryl group; an alkoxysilylalkyl group; an arylphosphine group; or a heterocyclic group containing at least one of N, O and S atoms, or being unsubstituted or substituted with a substituent to which two or more substituents are linked among the substituents exemplified above. For example, “the substituent to which two or more substituents are connected” may be a biphenyl group. Namely, the biphenyl group may also be an aryl group, and may be interpreted as a substituent to which two phenyl groups are connected.
As used herein, the notation + or —, means a bond linked to another substituent group, and the direct bond means that a separate atom does not exist in a part represented by L.
As used herein, the aromatic is a characteristic that satisfies Huckel's rule, and a compound can be said to be aromatic if it satisfy all of the following three conditions according to Huckel's rule.
1) There must exist 4n+2 electrons which are fully conjugated by vacant p-orbital, unsaturated bond, unpaired electron pair, and so on.
2) 4n+2 electrons must constitute a planar isomer and form a ring structure.
3) All atoms in the ring must be able to participate in the conjugation.
As used herein, the aliphatic may be defined as aliphatic if it does not meet the above-mentioned aromatic requirements.
As used herein, the alkyl group is a monovalent functional group derived from an alkane, and may be linear or branched, and the carbon number of the linear alkyl group is not particularly limited, but preferably 1 to 20. Also, the carbon number of the branched alkyl group is 3 to 20. Specific examples of the alkyl group may include methyl, ethyl, propyl, n-propyl, isopropyl, butyl, n-butyl, isobutyl, tert-butyl, sec-butyl, 1-methyl-butyl, 1-ethyl-butyl, 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-ethyl-propyl, 1,1-dimethyl-propyl, isohexyl, 2-methylpentyl, 4-methylhexyl, 5-methylhexyl, 2,6-dimethylheptan-4-yl, and the like, but are not limited thereto. The alkyl group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.
As used herein, the cycloalkyl group is a monovalent functional group derived from a cycloalkane, which may be monocyclic or polycyclic, and is not particularly limited, but the carbon number thereof may be 3 to 20. According to another exemplary embodiment, the carbon number of the cycloalkyl group is 3 to 10. Specific examples include 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, bicyclo[2,2,1]heptyl, and like, but are not limited thereto. The cycloalkyl group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.
As used herein, the aryl group is a monovalent functional group derived from an arene, and is not particularly limited, but the carbon number thereof is preferably 6 to 20, and it may be a monocyclic aryl group or a polycyclic aryl group. The aryl group may be a phenyl group, a biphenyl group, a terphenyl group or the like as the monocyclic aryl group, but is not limited thereto. The polycyclic aryl group includes a naphthyl group, an anthracenyl group, a phenanthrenyl group, a pyrenyl group, a perylenyl group, a chrysenyl group, or the like, but is not limited thereto. The aryl group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.
As used herein, the alkylene group is a bivalent functional group derived from an alkane, and the description of the alkyl group as defined above can be applied except that it is a divalent functional group. For example, the alkylene group is linear or a branched, and can include methylene group, ethylene group, propylene group, isobutylene group, sec-butylene group, tert-butylene group, pentylene group, hexylene group, or the like. The alkylene group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.
As used herein, the arylene group is a bivalent functional group derived from an arene, and the description of the aryl group as defined above may be applied, except that it is a divalent functional group. For example, it can be a phenylene group, a biphenylene group, a terphenylene group, a naphthalene group, a fluorenyl group, a pyrenyl group, a phenanthrenyl group, a perylene group, a tetracenyl group, an anthracenyl group, or the like. The arylene group may be substituted or unsubstituted, and if substituted, examples of the substituent are as described above.
As used herein, the cycloalkylene group is a bivalent functional group derived from a cycloalkane, and the description of the cycloalkyl group as defined above may be applied, 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.
As used herein, the derivative compound means a compound that has been changed within the limit of not significantly changing the structure and properties of a matrix such as introduction of a functional group, oxidation, reduction, or substitution of atoms when an organic compound is used as a matrix.
Below, the present disclosure will be described in more detail.
According to one embodiment of the present disclosure, there can be provided a polyester polymer comprising: a polymer matrix containing a polyester repeating unit; and a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid that remain in the polymer matrix.
The present inventors have found through experiments that similarly to the polyester polymer of one embodiment, a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid are added as cocatalysts during the synthesis of the polyester polymer, thereby capable of improving the production efficiency of the polyester polymer and maintaining excellent physical properties, and completed the invention.
The mono-metallic salt of the polyvalent inorganic acid and the multi-metallic salt of the polyvalent inorganic acid may be added as cocatalysts together with diol monomers, and dicarboxylic acids or derivatives thereof, and a main catalyst in the process of synthesizing the polyester polymer, and some or all thereof may remain in the finally synthesized polyester copolymer.
Specifically, the polyester polymer may include a polymer matrix including a polyester repeating unit. The polyester polymer may include both a homopolymer and a copolymer depending on the kind of polyester repeating unit. That is, the polymer matrix may include at least one, or two or more polyester repeating units. When one kind of polyester repeating unit is included in the polymer matrix, a polyester homopolymer may be formed, and when two or more kinds of polyester repeating units are included, a polyester polymer may be formed.
The polyester homopolymer may be a polyester polymer synthesized by reacting one kind of diol with one kind of carboxylic acid or a derivative thereof, and the polyester polymer is a polyester polymer synthesized by reacting one kind of diol with two or more kinds of dicarboxylic acids or derivatives thereof, or a polyester polymer synthesized by reacting two or more kinds of diols with one kind of dicarboxylic acid or a derivative thereof, or a polyester polymer synthesized by reacting two or more kinds of diols with two or more kinds of dicarboxylic acids or derivatives thereof.
The polyester repeating unit means a repeating unit containing a polyester functional group in the repeating unit structure, and may specifically have a structure represented by the following Chemical Formula 1:
wherein, in 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, or an arylene group having 6 to 20 carbon atoms, and R2 is an alkylene group having 1 to 10 carbon atoms.
As a more specific example, in Chemical Formula 1, R1 may be an arylene group having 6 to 20 carbon atoms or 6 to 8 carbon atoms, and R2 may be an alkylene group having 1 to 10 carbon atoms or 1 to 5 carbon atoms. As an example, in Chemical Formula 1, R1 may be a phenylene group, and R2 may be a butylene group.
The polyester repeating unit may include a reaction product of a dicarboxylic acid or a derivative thereof and a diol, an example of the dicarboxylic acid or its derivative includes terephthalic acid, which is an aromatic dicarboxylic acid, and an example of the diol includes 1,4-butanediol, which is an aliphatic diol.
Meanwhile, the polyester polymer may include a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid that remain in the polymer matrix. The mono-metallic salt of the polyvalent inorganic acid and the multi-metallic salt of the polyvalent inorganic acid may be added as cocatalysts together with diol monomers, and dicarboxylic acids or derivatives thereof, and a main catalyst in the process of synthesizing the polyester polymer, and some or all thereof may remain in the finally synthesized polyester polymer.
This can be confirmed through inductively coupled plasma (ICP) analysis of the finally synthesized polyester polymer. Specifically, through quantitative analysis of metal elements (e.g., Na and S) using ICP, the presence of two kinds of metallic salt cocatalysts of polyvalent inorganic acids remaining in the polyester polymer can be confirmed. In addition, the content and ratio of the two kinds of metallic salt cocatalysts of the polyvalent inorganic acid can be confirmed through ion chromatography analysis or combination analysis of ICP and Ion Chromatography.
The multi-metallic salt of the polyvalent inorganic acid means a salt obtained by acid-base neutralization reaction between a basic compound containing a metal component and a polyvalent inorganic acid, and particularly, it refers to a case in which di- or higher metallic components are included in the final salt compound. That is, in the chemical formula of a metallic salt of a polyvalent inorganic acid, if the number of metal components is two or more, it is defined as a multi-metallic salt of a polyvalent inorganic acid.
The multi-metallic salt of the polyvalent inorganic acid may include a di-metallic salt of a polyvalent inorganic acid, a tri-metallic salt of a polyvalent inorganic acid, a tetra-metallic salt of a polyvalent inorganic acid, or a penta-metallic salt of a polyvalent inorganic acid, depending on the number of metal components.
An example of the di-metallic salt of a polyvalent inorganic acid among the multi-metallic salt of a polyvalent inorganic acid includes sodium sulfate (Na2SO4), sodium hydrogen phosphate (Na2HPO4), and trisodium phosphate (Na3PO4).
The multi-metallic salt of the polyvalent inorganic acid can act as a cocatalyst in the process of synthesizing the polyester polymer, thereby shortening the polymerization time of the polyester polymer.
Further, the mono-metallic salt of the polyvalent inorganic acid refers to a salt obtained by an acid-base neutralization reaction between a basic compound containing a metal component and a polyvalent inorganic acid, and particularly refers to a case in which one (mono) metal component is included in the final salt compound. Namely, in the chemical formula of a metallic salt of a polyvalent inorganic acid, if the number of metal components is one, it is defined as a mono-metallic salt of a polyvalent inorganic acid. An example of the mono-metallic salt of the polyvalent inorganic acid include sodium bisulfate (NaHSO4) or sodium dihydrogen phosphate (NaH2PO4).
The mono-metallic salt of the polyvalent inorganic acid acts as a cocatalyst in the process of synthesizing the polyester polymer, and assists in shortening the polymerization time of the polyester polymer by the multi-metallic salt of the polyvalent inorganic acid, so that polymerization time can be sufficiently shortened even with a smaller amount of multi-metallic salt of a polyvalent inorganic acid, which can improve the efficiency of the process.
Therefore, when a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid are used in combination, a sufficient effect of shortening the polymerization time can be achieved even with a smaller amount of the multi-metallic salt of the polyvalent inorganic acid due to the mono-metallic salt of the polyvalent inorganic acid. On the other hand, when only one kind of mono-metallic salt of a polyvalent inorganic acid is used, there is a problem that the polymerization time of the polyester polymer is increased to more than 140 minutes and the polymerization time is not sufficiently shortened. When only one kind of multi-metallic salt of a polyvalent inorganic acid is used, an excessive amount of the multi-metallic salt of a polyvalent inorganic acid must be added to shorten the polymerization time to a sufficient level, which makes it difficult to secure process efficiency.
Specifically, the weight ratio of the multi-metallic salt of the polyvalent inorganic acid may be 10 parts by weight or more, or 20 parts by weight or more, or 1000 parts by weight or less, or 500 parts by weight or less, or 100 parts by weight or less, or 50 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 10 parts by weight to 500 parts by weight, or 20 parts by weight to 500 parts by weight, or 10 parts by weight to 100 parts by weight, or 20 parts by weight to 100 parts by weight, or 10 parts by weight to 50 parts by weight, or 20 parts by weight to 50 parts by weight, or 20 parts by weight to 30 parts by weight, or 10 parts by weight to 20 parts by weight, or 10 parts by weight to 15 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid.
When the weight ratio of the multi-metallic salt of a polyvalent inorganic acid is excessively reduced to less than 10 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid, it is difficult to sufficiently realize the effect of shortening the polymerization time of polyester polymers due to the multi-metallic salt of the polyvalent inorganic acid. When the weight ratio of the multi-metallic salt of the polyvalent inorganic acid is excessively increased to more than 1000 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid, there is a problem that an excessive amount of polyvalent inorganic acid multi-metallic salt must be added, which makes it difficult to secure process efficiency.
More specifically, the multi-metallic salt of the polyvalent inorganic acid may be contained in an amount of 10 ppm to 10000 ppm, or 10 ppm to 5000 ppm, or 10 ppm to 4000 ppm, or 10 ppm to 2000 ppm, or 10 ppm to 1500 ppm, or 100 ppm to 10000 ppm, or 100 ppm to 5000 ppm, or 100 ppm to 4000 ppm, or 100 ppm to 2000 ppm, or 100 ppm to 1500 ppm, or 500 ppm to 10000 ppm, or 500 ppm to 5000 ppm, or 500 ppm to 4000 ppm, or 500 ppm to 2000 ppm, or 500 ppm to 1500 ppm, or 1000 ppm to 10000 ppm, or 1000 ppm to 5000 ppm, or 1000 ppm to 4000 ppm, or 1000 ppm to 2000 ppm, or 1000 ppm to 1500 ppm based on the weight of the polyester polymer.
In addition, the mono-metallic salt of the polyvalent inorganic acid may be contained in an amount of 0.1 ppm to 150 ppm, or 1 ppm to 150 ppm, or 10 ppm to 150 ppm, or 50 ppm to 150 ppm, or 100 ppm to 150 ppm, or 0.1 ppm to 100 ppm, or 1 ppm to 100 ppm, or 10 ppm to 100 ppm, or 50 ppm to 100 ppm based on the weight of the polyester polymer.
The polyvalent inorganic acid is a polyprotic acid that can provide more than one hydrogen ion among inorganic acids, and may include a divalent inorganic acid, a trivalent inorganic acid, a tetravalent inorganic acid, a pentavalent inorganic acid, and the like according to the number of hydrogen ions. More specifically, examples of the polyvalent inorganic acid may include sulfuric acid or phosphoric acid.
The metal may include an alkali metal or an alkaline earth metal, and specific examples of the metal include sodium, potassium, calcium, magnesium, or mixtures thereof.
The polyester polymer may have a yellowness index (YI) of 24 or less, or 20 or less, or 15 or less, or 10 or less, or 1 or more, or 1 to 24, or 1 to 20, or 1 to 15, or 1 to 10, as measured using a color meter. When the yellowness index of the polyester polymer is excessively increased to more than 24 as measured using a color meter, there is a problem that it is difficult to secure a high level of transparency due to excessive yellow discoloration.
The polyester polymer may have a melting point (Tm) of 150° C. or more, or 200° C. or more, or 210° C. or more, or 220° C. or more, or 223° C. or more, or 250° C. or less, or 240° C. or less, or 150° C. to 250° C., or 200° C. to 250° C., or 210° C. to 250° C., or 220° C. to 250° C., or 223° C. to 250° C., or 150° C. to 240° C., or 200° C. to 240° C., or 210° C. to 240° C., or 220° C. to 240° C., or 223° C. to 240° C., as measured by differential scanning calorimetry. An example of the differential scanning calorimeter for measuring the melting point includes Differential Scanning calorimetry (device name: DSC 2920, producer: TA Instruments). The melting point can be determined through a temperature-heat flow graph obtained by scanning at a temperature rise rate or a cooling rate of 5° C./min or more and 15° C./min or less in the temperature range of 0° C. or more and 250° C. or less. More specifically, the melting point (Tm) was obtained through peak analysis of a heating curve of heat flow when the second temperature rises.
When the melting point (Tm) of the polyester polymer measured by differential scanning calorimetry is excessively reduced to less than 150° C., there may be a problem that process efficiency is reduced in the molding process for the polyester polymer.
The polyester polymer may have a crystallization temperature of 70° C. or more, or 150° C. or more, or 160° C. or more, or 170° C. or more, or 180° C. or more, or 183° C. or more, or 184° C. or more, or 200° C. or less, or 190° C. or less, or 70° C. to 200° C., or 150° C. to 200° C., or 160° C. to 200° C., or 170° C. to 200° C., or 180° C. to 200° C., or 183° C. to 200° C., or 184° C. to 200° C., or 70° C. to 190° C., or 150° C. to 190° C., or 160° C. to 190° C., or 170° C. to 190° C., or 180° C. to 190° C., or 183° C. to 190° C., or 184° C. to 190° C., as measured by differential scanning calorimetry. Examples of the differential scanning calorimetry for measuring the crystallization temperature include Differential Scanning calorimetry (device name: DSC 2920, producer: TA instruments). The crystallization temperature can be determined through a temperature-heat flow graph obtained by scanning at a temperature rise rate or a cooling rate of 5° C./min or more and 15° C./min or less in the temperature range of 0° C. or more and 250° C. or less. More specifically, the crystallization temperature (Tc) can be obtained through peak analysis of a cooling curve of heat flow during the first cooling.
When the crystallization temperature of the poly(ether ester) copolymer measured by a differential scanning calorimeter is excessively decreased to less than 70° C., there is a possibility that the process efficiency is reduced in the molding process for the polyester copolymer.
The polyester polymer may have a lower limit of intrinsic viscosity of 0.5 dL/g or more, or 0.6 dL/g or more, or 0.7 dL/g or more, or 0.8 dL/g or more, or 0.9 dL/g or more, or 0.95 dL/g or more, or 0.96 dL/g or more, or 0.97 dL/g or more, and an upper limit of 10 dL/g or less, or 5 dL/g or less, or 1 dL/g or less, or 0.98 dL/g or less, as measured in accordance with DIN-53728-3. The upper numerical range and the lower numerical range can be combined to satisfy any numerical range between the lower limit and the upper limit. As an example of a numerical range between the lower limit and the upper limit, the intrinsic viscosity measured in accordance with DIN-53728-3 can be 0.5 dL/g to 10 dL/g.
The use of the polyester polymer is not particularly limited, and the fields of application of thermoplastic polyester polymers known hitherto can be introduced without limitation. However, as an example, it can be used for various applications such as automobile parts, automobile interior materials, automobile exterior materials, cables, wires, hoses, tubes, antenna covers, leisure goods, and sporting goods.
Examples of molding processes for application to such uses are not limited, various thermoplastic polyester polymer molding processes known hitherto can be applied without limitation.
According to another embodiment of the present disclosure, there can be provided a method for preparing a polyester polymer, comprising the steps of: a) an esterification reaction step of reacting a diol, and a dicarboxylic acid or a derivative thereof in the presence of a catalyst and a cocatalyst; b) a first polycondensation step of introducing the catalyst to the reaction mixture in which the step a) is completed and performing polycondensation under reduced pressure to prepare a prepolymer; and c) a second polycondensation step of performing polycondensation of the prepolymer under a lower pressure condition than that of the step b), wherein the cocatalyst includes a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid.
Specifically, the method for preparing a polyester polymer may comprise a) an esterification reaction step of reacting a diol, and a dicarboxylic acid or a derivative thereof in the presence of a catalyst and a cocatalyst.
In the present disclosure, the diol is an aliphatic or alicyclic diol having 2 to 10 carbon atoms, and preferably has a molecular weight of 300 g/mol or less from the viewpoint of realizing the effects of the present disclosure. Specifically, examples of diols that can be used herein include 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-cyclohexane dimethanol, and tricyclodecane dimethanol; and the like, but are not limited thereto. Specifically, in the present disclosure, the diol may be 1,4-butanediol which is an aliphatic diol.
Examples of dicarboxylic acids that can be used herein include terephthalic acid, isophthalic acid, naphthalenedicarboxylic acid, adipic acid, and sebacic acid, but are not limited thereto. Specifically, the dicarboxylic acid may be terephthalic acid. Examples of dicarboxylic acid derivatives that can be used herein include dialkyl terephthalate, dialkyl isophthalate, dialkyl naphthalenedicarboxylate, dialkyl adipic acid ester, and dialkyl sebacic acid ester, but are not limited thereto. Specifically, the dicarboxylic acid or a derivative thereof may be dimethyl terephthalate, which is a derivative of an aromatic dicarboxylic acid.
The esterification reaction of reacting the diol, and dicarboxylic acid or a derivative thereof is performed in the presence of a catalyst (main catalyst) and a cocatalyst, wherein as the catalyst (main catalyst), any material known in the art may be appropriately used. Specifically, the catalyst (main catalyst) may be a catalyst containing titanium or tin as an active metal. More specifically, as the catalyst, titanium-based catalysts such as tetrabutyl titanate (TBT), tetraethyl titanate or tetra(isopropyl) titanate; or 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 can be used. Further, in addition to the above-mentioned catalysts, catalysts such as oxides or acetates containing Mg, Ca, Mn, Zn, Pb, Zr and the like as active metals can be used singly or in combination. Among them, a titanium-based catalyst such as TBT may be preferably used.
Meanwhile, in the present disclosure, the catalyst is introduced in the polycondensation step as well as in the esterification reaction. Generally, when preparing polyester polymers, the catalyst of esterification (or transesterification) and the polycondensation reaction is the same as each other. Since no separation process is included between the two reactions, a predetermined amount of the catalyst is introduced at the beginning of the first esterification (or transesterification) reaction or during the reaction, and then the catalyst may not be further added in the polycondensation step.
The cocatalyst may include a mono-metallic salt of a polyvalent inorganic acid and a di-metallic salt of a polyvalent inorganic acid. The multi-metallic salt of the polyvalent inorganic acid refers to a salt obtained by acid-base neutralization reaction between a basic compound containing a metal component and a polyvalent inorganic acid, and particularly, it refers to a case in which two or more metal components are included in the final salt compound. That is, in the chemical formula of a metallic salt of a polyvalent inorganic acid, if the number of metal components is two or more, it is defined as a multi-metallic salt of a polyvalent inorganic acid.
The multi-metallic salt of the polyvalent inorganic acid may include a di-metallic salt of a polyvalent inorganic acid, a tri-metallic salt of a polyvalent inorganic acid, a tetra-metallic salt of a polyvalent inorganic acid, or a penta-metallic salt of a polyvalent inorganic acid, depending on the number of metal components.
Examples of di-metallic salts of polyvalent inorganic acids among the multi-metallic salts of polyvalent inorganic acids include sodium sulfate (Na2SO4), sodium hydrogen phosphate (Na2HPO4), and trisodium phosphate (Na3PO4).
The multi-metallic salt of the polyvalent inorganic acid may act as a cocatalyst in the process of synthesizing the polyester polymer, and can play a role in shortening the polymerization time of the polyester polymer.
In addition, the mono-metallic salt of the polyvalent inorganic acid means a salt obtained by an acid-base neutralization reaction between a basic compound containing a metal component and a polyvalent inorganic acid, and particularly, it refers to a case in which one (mono) metal component is included in the final salt compound. That is, in the chemical formula of the metallic salt of a polyvalent inorganic acid, if the number of metal components is one, it is defined as a mono-metallic salt of a polyvalent inorganic acid. An example of the mono-metallic salt of the polyvalent inorganic acid include sodium bisulfate (NaHSO4) or sodium dihydrogen phosphate (NaH2PO4).
The mono-metallic salt of the polyvalent inorganic acid acts as a cocatalyst in the process of synthesizing the polyester polymer, and assists in shortening the polymerization time of the polyester polymer due to the multi-metallic salt of the polyvalent inorganic acid, so that polymerization time can be sufficiently shortened even with a smaller amount of multi-metallic salt of a polyvalent inorganic acid, and the efficiency of the process can be improved.
Therefore, when a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid are used in combination, a sufficient effect of shortening the polymerization time can be realized even with a smaller amount of multi-metallic salt of a polyvalent inorganic acid due to the mono-metallic salt of a polyvalent inorganic acid. On the other hand, when only one kind of mono-metallic salt of a polyvalent inorganic acid is used, the polymerization time of the polyester polymer increases to more than 140 minutes, which may cause a problem that the polymerization time is not sufficiently shortened. If only one kind of multi-metallic salt of a polyvalent inorganic acid is used, an excessive amount of multi-metallic salt of a polyvalent inorganic acid must be added in order to shorten the polymerization time to a sufficient level, there is a problem that it is difficult to secure the efficiency of the process.
Specifically, the weight ratio of the multi-metallic salt of a polyvalent inorganic acid may be 10 parts by weight or more, or 20 parts by weight or more, or 1000 parts by weight or less, or 500 parts by weight or less, or 100 parts by weight or less, or 50 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 10 parts by weight to 500 parts by weight, or 20 parts by weight to 500 parts by weight, or 10 parts by weight to 100 parts by weight, or 20 parts by weight to 100 parts by weight, or 10 parts by weight to 50 parts by weight, or 20 parts by weight to 50 parts by weight, or 20 parts by weight to 30 parts by weight, or 10 parts by weight to 20 parts by weight, or 10 parts by weight to 15 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid.
When the weight ratio of the multi-metallic salt of a polyvalent inorganic acid is excessively reduced to less than 10 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid, it is difficult to sufficiently realize the effect of shortening the polymerization time of polyester polymers due to the use of multi-metallic salts of inorganic acids. When the weight ratio of the multi-metallic salt of the polyvalent inorganic acid is excessively increased to more than 1000 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid, there is a problem that an excessive amount of inorganic acid multi-metallic salt must be added, which makes it difficult to secure the efficiency of the process.
More specifically, the multi-metallic salt of the polyvalent inorganic acid may be contained in an amount of 10 ppm to 10000 ppm, or 10 ppm to 5000 ppm, or 10 ppm to 4000 ppm, or 10 ppm to 2000 ppm, or 10 ppm to 1500 ppm, or 100 ppm to 10000 ppm, or 100 ppm to 5000 ppm, or 100 ppm to 4000 ppm, or 100 ppm to 2000 ppm, or 100 ppm to 1500 ppm, or 500 ppm to 10000 ppm, or 500 ppm to 5000 ppm, or 500 ppm to 4000 ppm, or 500 ppm to 2000 ppm, or 500 ppm to 1500 ppm, or 1000 ppm to 10000 ppm, or 1000 ppm to 5000 ppm, or 1000 ppm to 4000 ppm, or 1000 ppm to 2000 ppm, or 1000 ppm to 1500 ppm based on the weight of the reaction mixture in which the step a) is completed.
In addition, the mono-metallic salt of the polyvalent inorganic acid may be contained in an amount of 0.1 ppm to 150 ppm, or 1 ppm to 150 ppm, or 10 ppm to 150 ppm, or 50 ppm to 150 ppm, or 100 ppm to 150 ppm, or 0.1 ppm to 100 ppm, or 1 ppm to 100 ppm, or 10 ppm to 100 ppm, or 50 ppm to 100 ppm based on the weight of the reaction mixture at which the step has been completed.
The polyvalent inorganic acid is a polyprotic acid that can provide more than one hydrogen ion among inorganic acids, and may include divalent inorganic acids, trivalent inorganic acids, tetravalent inorganic acids, pentavalent inorganic acids, etc. according to the number of hydrogen ions. More specifically, examples of the polyvalent inorganic acid may include sulfuric acid or phosphoric acid.
The metal may include an alkali metal or an alkaline earth metal, and specific examples of the metal include sodium, potassium, calcium, magnesium, or mixtures thereof.
Meanwhile, in the present disclosure, a certain amount of the cocatalyst may be added at the start of the first esterification (or transesterification) reaction, at the initial state of the reaction, or at the end of the reaction, and if necessary, it may be additionally added in the polycondensation step.
The reaction temperature in the step a) is preferably in the range of 150° C. or more and 300° C. or less, or 200° C. or more and 240° C. or less, and the reaction pressure may be in the range of 100 torr or more and 760 torr or less. Specifically, after the starting material and the catalyst were added to a reactor, the temperature was raised to 0.1° C./min or more and 10° C./min or less under stirring to reach the above temperature range, and then the esterification reaction can be performed for about 30 minutes to 4 hours, or 1 to 2 hours.
When the step a) is completed, the polycondensation steps b) and c) are then performed. The polycondensation step may be performed in a reactor separate from the esterification reactor, and can be performed without a distillation column. Specifically, the polycondensation step is performed after adding a catalyst of 50 ppm or more based on active metal to the reaction mixture in which the step a) is completed.
In the present disclosure, the polycondensation step is divided into two steps b) and c). The steps b) and c) are performed substantially continuously, but there is a difference in pressure conditions. Specifically, the step b) is a step of removing excess diol, and the step c) is a step of increasing the viscosity of the polyester polymer.
Specifically, the method for preparing the polyester polymer may comprise b) a first polycondensation step of introducing the catalyst to the reaction mixture in which the step a) is completed and performing polycondensation under reduced pressure to prepare a prepolymer.
The step b) of the present disclosure is a first polycondensation step performed under relatively mild conditions, and is a step of adding a catalyst to the reaction mixture in which the step a) is completed, subjecting the reaction mixture to a polycondensation while stirring under reduced pressure to obtain a prepolymer.
The step b) may be performed under the conditions of a temperature of 180° C. to 250° C. and a pressure of 5 torr to 100 torr. Under these conditions, excess diol unreacted in step a) is vaporized and removed. The reaction time of the step b) is not particularly limited, but may be 20 minutes to 1 hour, or 20 minutes to 40 minutes.
If the polycondensation proceeds immediately in a high vacuum of 5 torr or less without performing the step b), vaporization of unreacted diol may occur rapidly to cause a bumping phenomenon in the reactor, and a temperature decrease of the reactant may be intensified. Moreover, there may be a problem that the polyester polymer cannot be obtained with high viscosity. Therefore, in the present disclosure, the first polycondensation step is preliminarily performed under mild conditions before the full-scale polycondensation reaction.
On the other hand, in the step a) or b), in order to improve the reaction efficiency and adjust the physical properties of the polyester polymer produced, one or more commonly used additives can be added together.
Examples of usable additives include a branching agent for increasing the melt strength of polyester polymers (e.g., glycerol, sorbitol, pentaerythritol, 1,1,4,4-tetrakis(hydroxymethyl)cyclohexane, trimethylol propane, pyromellitic acid, 1,1,2,2-ethanetetracarboxylic acid, etc.), a matting agent for improving color characteristics (e.g. TiO2, zinc sulfide or zinc oxide), a colorant (e.g., dye), a stabilizer (e.g., antioxidant, ultraviolet light stabilizer, heat stabilizer, etc.), a filler, a flame retardant, a pigment, an antimicrobial agent, an antistatic agent, an optical brightener, an extender, a processing aid, a viscosity enhancer, or the like, and any one or a mixture of two or more of these can be mentioned, but is not limited thereto. As an example, in order to increase the thermal stability of the polyester polymer, a stabilizer in the form of hindered phenol (e.g., Irganox 1330) can be added.
These additives can be used in an appropriate amount within the range that secures the desired effect and does not deteriorate the physical properties of the polyester polymer produced. Specifically, the additive can be used in an amount of 0.1 to 10% by weight based on 100% by weight in total of the raw material.
In addition, the method for preparing the polyester polymer may comprise c) a second polycondensation step of performing polycondensation of the prepolymer under a lower pressure condition than that of the step b).
The step c) is a reaction continuing with the step b), and is a step of performing polycondensation of the prepolymer in the same reactor in a state where the pressure is further lowered.
In the step c), the time from a point of time at which the reaction starts to a point of time at which a torque value attached to a mechanical stirrer reaches 0.8 Nm to stop the reaction may be 95 minutes or less, or 91 minutes or less, or 90 minutes or less, or 80 minutes or less, or 70 minutes or less, or 50 minutes or more, or 50 minutes to 95 minutes, or 50 minutes to 90 minutes, or 50 minutes to 80 minutes, or 50 minutes to 70 minutes. In the step c), if the time from a point of time at which the reaction starts to a point of time at which a torque value attached to a mechanical stirrer reaches 0.8 Nm to stop the reaction increases excessively, there is a problem that it is difficult to sufficiently shorten the polymerization time, and productivity decreases.
The step c) may be performed under the conditions of a temperature of 180° C. to 250° C. and a pressure of 5 torr or less. Under these conditions, polycondensation is performed for about 30 minutes to 5 hours, or 1 to 3 hours, and the reaction is completed when the torque value reaches the range of 0.5 Nm to 2.0 Nm, thereby finally prepare a polyester polymer.
According to yet another embodiment of the present disclosure, there can be provided a catalyst system comprising a catalyst and a cocatalyst, wherein the cocatalyst includes a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid.
The catalyst system can be applied to the synthesis of various polymers, specific examples of the polymers are not particularly limited thereto, and conventionally known polymers can be applied without limitation. However, as an example, polyester (co) polymer, polyether ester copolymer, polyolefin (co) polymer, polycarbonate (co) polymer, polyurethane (co) polymer, polyamide (co) polymer, polyimide (co) polymer, polysulfone (co) polymer, polyacetal (co) polymer, polyketone (co) polymer, polyacrylic (co) polymers and the like can be used. The (co) polymer is meant to include both homopolymers and copolymers.
As the catalyst (main catalyst), any material known in the art can be appropriately used. Specifically, the catalyst (main catalyst) may be a catalyst containing titanium or tin as an active metal. More specifically, as the catalyst, titanium-based catalysts such as tetrabutyl titanate (TBT), tetraethyl titanate or tetra(isopropyl) titanate; or tin-based catalysts 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 can be used. Further, in addition to the above-mentioned catalysts, catalysts such as oxides or acetates containing Mg, Ca, Mn, Zn, Pb, Zr and the like as active metals can be used singly or in combination. Among them, a titanium-based catalyst such as TBT may be preferably used.
The cocatalyst may include a mono-metallic salt of a polyvalent inorganic acid and a di-metallic salt of a polyvalent inorganic acid. The multi-metallic salt of the polyvalent inorganic acid refers to a salt obtained by acid-base neutralization reaction between a basic compound containing a metal component and a polyvalent inorganic acid, and particularly, it refers to a case in which two (di) or higher metal components are included in the final salt compound. That is, in the chemical formula of a metallic salt of a polyvalent inorganic acid, if the number of metal components is two or more, it is defined as a multi-metallic salt of a polyvalent inorganic acid.
The multi-metallic salt of the polyvalent inorganic acid may include a di-metallic salt of a polyvalent inorganic acid, a tri-metallic salt of a polyvalent inorganic acid, a tetra-metallic salt of a polyvalent inorganic acid, or a penta-metallic salt of a polyvalent inorganic acid, depending on the number of metal components.
Examples of di-metallic salts of polyvalent inorganic acids among the multi-metallic salts of polyvalent inorganic acids include sodium sulfate (Na2SO4), sodium hydrogen phosphate (Na2HPO4), and trisodium phosphate (Na3PO4).
The multi-metallic salt of the polyvalent inorganic acid may act as a cocatalyst in the process of synthesizing the polyester polymer, and can play a role in shortening the polymerization time of the polyester polymer.
In addition, the mono-metallic salt of the polyvalent inorganic acid means a salt obtained by an acid-base neutralization reaction between a basic compound containing a metal component and a polyvalent inorganic acid, and particularly, it refers to a case in which one (mono) metal component is included in the final salt compound. That is, in the chemical formula of the metallic salt of a polyvalent inorganic acid, if the number of metal components is one, it is defined as a mono-metallic salt of a polyvalent inorganic acid. An example of the mono-metallic salt of the polyvalent inorganic acid include sodium bisulfate (NaHSO4) or sodium dihydrogen phosphate (NaH2PO4).
The mono-metallic salt of the polyvalent inorganic acid acts as a cocatalyst in the process of synthesizing the polyester polymer, and assists in shortening the polymerization time of the polyester polymer due to the multi-metallic salt of the polyvalent inorganic acid, so that polymerization time can be sufficiently shortened even with a smaller amount of multi-metallic salt of a polyvalent inorganic acid, and the efficiency of the process can be improved.
Therefore, when a mono-metallic salt of a polyvalent inorganic acid and a multi-metallic salt of a polyvalent inorganic acid are used in combination, a sufficient effect of shortening the polymerization time can be realized even with a smaller amount of multi-metallic salt of a polyvalent inorganic acid due to the mono-metallic salt of a polyvalent inorganic acid. On the other hand, when only one kind of mono-metallic salt of a polyvalent inorganic acid is used, there is a problem that the polymerization time is not sufficiently shortened. If only one kind of multi-metallic salt of a polyvalent inorganic acid is used, an excessive amount of multi-metallic salt of a polyvalent inorganic acid must be added in order to shorten the polymerization time to a sufficient level, there is a problem that it is difficult to secure the efficiency of the process.
Specifically, the weight ratio of the multi-metallic salt of a polyvalent inorganic acid may be 10 parts by weight or more, or 20 parts by weight or more, or 1000 parts by weight or less, or 500 parts by weight or less, or 100 parts by weight or less, or 50 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 10 parts by weight to 500 parts by weight, or 20 parts by weight to 500 parts by weight, or 10 parts by weight to 100 parts by weight, or 20 parts by weight to 100 parts by weight, or 10 parts by weight to 50 parts by weight, or 20 parts by weight to 50 parts by weight, or 20 parts by weight to 30 parts by weight, or 10 parts by weight to 20 parts by weight, or 10 parts by weight to 15 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid.
When the weight ratio of the multi-metallic salt of an polyvalent inorganic acid is excessively reduced to less than 10 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid, it is difficult to sufficiently realize the effect of shortening the polymerization time of polyester polymers due to the use of multi-metallic salts of polyvalent inorganic acids. When the weight ratio of the multi-metallic salt of the polyvalent inorganic acid is excessively increased to more than 1000 parts by weight with respect to 1 part by weight of the mono-metallic salt of the polyvalent inorganic acid, there is a problem that an excessive amount of polyvalent inorganic acid multi-metallic salt must be added, which makes it difficult to secure the efficiency of the process.
More specifically, the multi-metallic salt of the polyvalent inorganic acid may be contained in an amount of 10 ppm to 10000 ppm, or 10 ppm to 5000 ppm, or 10 ppm to 4000 ppm, or 10 ppm to 2000 ppm, or 10 ppm to 1500 ppm, or 100 ppm to 10000 ppm, or 100 ppm to 5000 ppm, or 100 ppm to 4000 ppm, or 100 ppm to 2000 ppm, or 100 ppm to 1500 ppm, or 500 ppm to 10000 ppm, or 500 ppm to 5000 ppm, or 500 ppm to 4000 ppm, or 500 ppm to 2000 ppm, or 500 ppm to 1500 ppm, or 1000 ppm to 10000 ppm, or 1000 ppm to 5000 ppm, or 1000 ppm to 4000 ppm, or 1000 ppm to 2000 ppm, or 1000 ppm to 1500 ppm based on the weight of the reaction mixture in which the step a) is completed.
In addition, the mono-metallic salt of the polyvalent inorganic acid may be contained in an amount of 0.1 ppm to 150 ppm, or 1 ppm to 150 ppm, or 10 ppm to 150 ppm, or 50 ppm to 150 ppm, or 100 ppm to 150 ppm, or 0.1 ppm to 100 ppm, or 1 ppm to 100 ppm, or 10 ppm to 100 ppm, or 50 ppm to 100 ppm based on the weight of the reaction mixture at which the step has been completed.
The polyvalent inorganic acid is a polyprotic acid that can provide more than one hydrogen ion among polyvalent inorganic acids, and may include divalent inorganic acids, trivalent inorganic acids, tetravalent inorganic acids, pentavalent inorganic acids, etc. according to the number of hydrogen ions. More specifically, examples of the polyvalent inorganic acid may include sulfuric acid or phosphoric acid.
The metal may include an alkali metal or an alkaline earth metal, and specific examples of the metal include sodium, potassium, calcium, magnesium, or mixtures thereof.
According to the present disclosure, a polyester polymer that can significantly shorten a polymerization time and increase productivity, while maintaining a state of excellence in physical properties, a method for preparing the same, and a catalyst system can be provided.
Hereinafter, the present disclosure will be described in more detail with reference to examples. However, the following examples are for illustrative purposes only, and are not intended to limit the scope of the present disclosure.
120 g of terephthalic acid, 200 g of 1,4-butanediol, 50 ppm (based on Ti element) of tetrabutyl titanate (TBT) catalyst, and 1,200 ppm (based on total raw material input) of sodium sulfate (Na2SO4) and 50 ppm (based on total raw material input) of sodium bisulfate (NaHSO4) as cocatalysts were introduced into to a 2L glass reactor, and stirred up to 230° C. for 2 hours under a nitrogen atmosphere, and the temperature was raised, and an esterification (ES) reaction was performed under a pressure of 100 to 760 torr.
After the ES reaction, 50 ppm (based on Ti element) of tetrabutyl titanate (TBT) catalyst (based on Ti element) and 3000 ppm of Irganox 1330 as an antioxidant was introduced into the reactor, and then stirred for 10 minutes to remove the liquid by-product generated within a Dean-Stark trap. Then, the pressure was reduced up to 10 torr in the range of 230° C. to 240° C. for 30 minutes to perform a first polycondensation reaction.
Then, the second polycondensation reaction was performed at 240° C. to 250° C. and 1 torr or less. During the PC reaction, the torque value attached to a mechanical stirrer was continuously increased, and after 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 polybutylene terephthalate (PBT).
A PBT was obtained in the same manner as in Example 1, except that the content or kind of sodium sulfate (Na2SO4) and of sodium bisulfate (NaHSO4) as the cocatalysts were changed as shown in Table 1 below.
The physical properties of the polyester polymers obtained in Examples and Comparative Examples were measured by the following method, and the results are shown in Table 1 below.
In Examples and Comparative Examples, the time from a point of time at which the reaction started to a point of time at which a torque value attached to a mechanical stirrer reached 0.8 Nm to stop the reaction was measured.
2. Intrinsic Viscosity (Unit: dL/g)
The polyester polymers obtained in Examples and Comparative Examples were dried in an oven at 80° C. for 2 hours or more, the resulting sample was dissolved in a mixed solvent of o-cresol/1,2-dichlorobenzene (weight ratio 1:1), and then the intrinsic viscosity was measured at 25° C. using an Ubbelohde viscometer in the same manner as DIN-53728-3.
With respect to the polyester polymers obtained in Examples and Comparative Examples, the melting point (Tm) and crystallization temperature (Tc) were measured on a temperature-heat flow graph obtained by scanning twice at a temperature rise rate or a cooling rate of 10° C./min in the temperature range of 0° C. or more and 250° C. or less using Differential Scanning calorimetry (device name: DSC 2920, producer: TA Instruments).
The crystallization temperature (Tc) was obtained through peak analysis of the cooling curve of heat flow during the first cooling, and the melting point (Tm) was obtained through peak analysis of the heating curve of heat flow during the second temperature rise.
The yellowness index of the polyester polymers obtained in Examples and Comparative Examples were measured using Color meter ZE6000 (NIPPON DENSHOKU).
As shown in Table 1, the polyester polymers of Examples 1 to 2 exhibited the intrinsic viscosity, melting point, crystallization temperature, yellowness index physical properties of levels equivalent to Comparative Examples, and at the sample time, the PC reaction time was shortened to 70 minutes, or 91 minutes, thereby being able to increase the process efficiency through a short PC reaction time as compared with Comparative Examples having a PC reaction time of 97 minutes, 112 minutes, or 120 minutes.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10-2022-0168706 | Dec 2022 | KR | national |
| 10-2023-0065848 | May 2023 | KR | national |
This application is a National Phase entry pursuant to 35 U.S.C. § 371 of International Application No. PCT/KR2023/007803, filed on Jun. 8, 2023, and claims the benefit of and priority to Korean Patent Application No. 10-2022-0168706, filed on Dec. 6, 2022 and Korean Patent Application No. 10-2023-0065848, filed on May 22, 2023 in the Korean Intellectual Property Office, the disclosures of which are hereby incorporated by reference in their entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/KR2023/007803 | 6/8/2023 | WO |
