Polyester-based polymer having improved cold resistance, chemical resistance, and elasticity

Abstract

A polyester-based polymer according to the present invention contains 30 mol% or more of cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof as a dicarboxylic acid component, and thus is environmentally friendly, has controlled softness, and has excellent quality and processability. In addition, the polyester-based polymer includes a linear C3-C6 alkanediol or the like as a diol component, thereby improving cold resistance, chemical resistance, and elasticity while having softness.

Description

Polyester polymer with improved cold resistance, chemical resistance, and elasticity

[0001] The present invention relates to a polyester polymer that is environmentally friendly and has improved cold resistance, chemical resistance, and elasticity.

[0002] Polyvinyl chloride (PVC) is colorless and transparent, has excellent strength, and its properties can be easily adjusted depending on the type of additives used during processing. Therefore, it is widely used in various industries. For example, by adding a certain amount of plasticizer, a softening agent, to PVC, soft PVC can be produced, enabling the production of flexible products such as packaging films and shower curtains. By adding less than 10% by weight of plasticizer, rigid PVC can be produced, enabling the production of products such as plumbing materials. Thus, PVC boasts excellent productivity and processability, as its softness and rigidity can be easily controlled simply by adjusting the plasticizer content without additional processing. However, recent controversy surrounding the environmental and human hazards of phthalic and adipic acid-based plasticizers has led to restrictions on their use. Furthermore, PVC produces toxic dioxins when burned, making landfill disposal the only viable option. Therefore, the development of alternative materials to PVC is urgently needed.

[0003] Meanwhile, polyester boasts excellent mechanical properties, such as durability and heat resistance, and optical properties, such as transparency. This makes it widely used as a raw material for fibers, films, packaging materials, molded products, building materials, interior and exterior finishes, and various industrial materials, such as display devices. Furthermore, polyester is more environmentally friendly than PVC, as it can be recycled through mechanical and chemical recycling methods. Furthermore, it boasts superior mechanical and optical properties, making it a promising alternative to PVC. However, controlling flexibility and rigidity remains challenging. Therefore, research into polyesters that can effectively control flexibility and rigidity continues.

[0004] For example, Korean Patent Publication No. 2013-0122746 discloses a copolyester resin capable of controlling softness or hardness by attaching soft segments or hard segments.

[0005] (Patent Document 1) Korean Patent Publication No. 2013-0122746

[0006] Although existing amorphous soft polyesters offer excellent flexibility, they lack satisfactory cold resistance, chemical resistance, and elasticity. Therefore, the inventors of the present invention have conducted research to control the polymerization composition of amorphous soft polyesters, resulting in a polymer that possesses both flexibility and improved cold resistance, chemical resistance, and elasticity.

[0007] Accordingly, the present invention aims to provide a polyester polymer that is environmentally friendly and has excellent properties as polyester, and in particular, has softness while improving cold resistance, chemical resistance, and elasticity.

[0008] According to one aspect of the present invention, a polyester polymer is provided, which comprises a residue of a dicarboxylic acid component and a residue of a diol component, wherein the dicarboxylic acid component comprises a combination of a first dicarboxylic acid component and a second dicarboxylic acid component or a second dicarboxylic acid component, wherein the first dicarboxylic acid component comprises terephthalic acid, dimethyl terephthalate, or a combination thereof, wherein the second dicarboxylic acid component comprises cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof, wherein the content of the second dicarboxylic acid component is 30 mol% or more based on 100 mol% of the dicarboxylic acid component, and wherein the diol component comprises a linear C3-C6 alkanediol.

[0009] The polyester polymer according to the present invention is environmentally friendly, has controlled softness, and has excellent quality and processability, and can be used in the manufacture of various products including sheets and films by being applied to calendaring or T-die processes.

[0010] Specifically, the polyester polymer according to the present invention contains cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof in an amount of 30 mol% or more as a dicarboxylic acid component, and is thus environmentally friendly and has excellent mechanical properties such as softness and elasticity, optical properties such as transparency and UV stability, and processability.

[0011] In addition, while existing non-crystalline soft polyesters were not satisfactory in terms of cold resistance, chemical resistance, and elasticity, the polyester polymer according to the present invention contains linear C3-C6 alkanediol as a diol component, and thus can have improved cold resistance, chemical resistance, and elasticity while maintaining softness.

[0012] The present invention is described in detail below. The present invention is not limited to the details disclosed below and may be modified in various ways without altering the spirit of the invention.

[0013] In this specification, when a part is said to "include" a certain component, this does not mean that it excludes other components, but rather that it may include other components, unless otherwise specifically stated.

[0014] All numbers and expressions indicating the amounts of components, reaction conditions, etc. described in this specification should be understood to be modified by the term “about” in all cases unless otherwise specified.

[0015] In this specification, the terms "first," "second," etc. are used to describe various components, and the components are not limited by the terms. The terms are used only to distinguish one component from another.

[0016] The terms used herein to refer to each component are used to distinguish it from other components and are not intended to limit the embodiments. Furthermore, the singular expressions used herein include the plural expressions unless the context clearly dictates otherwise.

[0017] In the numerical ranges that limit the size, physical properties, etc. of the components described in this specification, if a numerical range limited only to the upper limit and a numerical range limited only to the lower limit are separately exemplified, it should be understood that a numerical range in which these upper and lower limits are combined is also included in the exemplary range of the present invention.

[0018]

[0019] polyester polymer

[0020] The polyester polymer comprises a residue of a dicarboxylic acid component and a residue of a diol component. The polyester polymer is formed by a polymerization reaction of the dicarboxylic acid component and the diol component, and as a result, the residue of the dicarboxylic acid component and the residue of the diol component exist within the chain of the polyester polymer.

[0021] The dicarboxylic acid component includes a combination of a first dicarboxylic acid component and a second dicarboxylic acid component or a second dicarboxylic acid. As an example, the polyester polymer may be a block copolymer or a random copolymer of a combination of the first dicarboxylic acid component and a second dicarboxylic acid component and a diol component, and including a residue of the first dicarboxylic acid component, a residue of the second dicarboxylic acid component, and a residue of the diol component. As another example, the polyester polymer may be a homopolymer in which the second dicarboxylic acid component is polymerized with the diol component, and including a residue of the second dicarboxylic acid component and a residue of the diol component.

[0022] In one embodiment, the dicarboxylic acid component essentially includes a second dicarboxylic acid component, and specifically, the dicarboxylic acid component includes a combination of the first dicarboxylic acid component and the second dicarboxylic acid component or the second dicarboxylic acid component.

[0023] The first dicarboxylic acid component comprises terephthalic acid (TPA), dimethyl terephthalate (DMT), or a combination thereof.

[0024] The first dicarboxylic acid component may comprise terephthalic acid, dimethyl terephthalate, or a combination thereof in an amount of at least 80 mol%, at least 85 mol%, at least 90 mol%, at least 95 mol%, at least 98 mol%, at least 99 mol%, or at least 100 mol%. As a specific example, the first dicarboxylic acid component may comprise terephthalic acid, dimethyl terephthalate, or a combination thereof in an amount of from 80 mol% to 100 mol%, from 85 mol% to 100 mol%, from 90 mol% to 100 mol%, or from 95 mol% to 100 mol%.

[0025] Additionally, the polyester polymer may contain the first dicarboxylic acid component in an amount of 5 mol% to 70 mol%, 8 mol% to 65 mol%, 10 mol% to 60 mol%, 13 mol% to 55 mol%, or 15 mol% to 50 mol% based on the total dicarboxylic acid component.

[0026] The content of the second dicarboxylic acid component is 30 mol% or more based on 100 mol% of the dicarboxylic acid component. When the content of the second dicarboxylic acid component satisfies the above range, the softness of the polyester polymer can be further improved. In one specific example, the content of the second dicarboxylic acid component may be 50 mol% or more based on 100 mol% of the dicarboxylic acid component. For example, the content of the second dicarboxylic acid component may be 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, or 70 mol% or more based on 100 mol% of the dicarboxylic acid component, and may also be 95 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, or 75 mol% or less. As a more specific example, the content of the second dicarboxylic acid component may be 30 mol% to 95 mol%, 40 mol% to 90 mol%, 50 mol% to 85 mol%, or 60 mol% to 80 mol% based on 100 mol% of the dicarboxylic acid component.

[0027] The second dicarboxylic acid component comprises cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof. More specifically, the second dicarboxylic acid component may be 1,4-cyclohexanedicarboxylic acid, dimethyl 1,4-cyclohexanedicarboxylate, or a combination thereof. Specifically, the second dicarboxylic acid component may comprise cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof in an amount of 80 mol% or more, 85 mol% or more, 90 mol% or more, 95 mol% or more, 98 mol% or more, 99 mol% or more, or 100 mol%.

[0028] A polyester polymer according to one embodiment of the present invention comprises a first dicarboxylic acid component including terephthalic acid, dimethyl terephthalate, or a combination thereof as a dicarboxylic acid component, and a second dicarboxylic acid component including cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof, thereby improving mechanical properties such as hardness and elasticity, optical properties such as transparency and UV stability, and processability while being environmentally friendly. In particular, since softness can be effectively controlled by adjusting the content of the second dicarboxylic acid component, productivity and processability are very excellent.

[0029] In one specific example, the second dicarboxylic acid component may include dimethylcyclohexanedicarboxylate. For example, the content of the dimethylcyclohexanedicarboxylate may be 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, or 70 mol% or more, based on 100 mol% of the dicarboxylic acid component, and may also be 95 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, or 75 mol% or less, and specifically, may be 30 mol% to 95 mol%, 40 mol% to 90 mol%, 50 mol% to 85 mol%, or 60 mol% to 80 mol%. When the content of the dimethylcyclohexanedicarboxylate satisfies the above range, the softness of the polyester copolymer can be further improved.

[0030] In another specific example, the second dicarboxylic acid component may include cyclohexanedicarboxylic acid. For example, the content of the cyclohexanedicarboxylic acid may be 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, or 70 mol% or more, based on 100 mol% of the dicarboxylic acid component, and may also be 95 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, or 75 mol% or less, and specifically, may be 30 mol% to 95 mol%, 40 mol% to 90 mol%, 50 mol% to 85 mol%, or 60 mol% to 80 mol%.

[0031] According to another embodiment of the present invention, the dicarboxylic acid component may additionally include a third dicarboxylic acid component.

[0032] Specifically, the third dicarboxylic acid component may be a dicarboxylic acid component different from the first and second dicarboxylic acid components. More specifically, the third dicarboxylic acid component may include at least one selected from the group consisting of succinic acid, adipic acid, sebacic acid, azelaic acid, dodecanoic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, dimethyl isophthalate, diethyl isophthalate, and dibutyl isophthalate.

[0033] The content of the third dicarboxylic acid component may be 30 mol% or less, 25 mol% or less, 15 mol% or less, 10 mol% or less, 5 mol% or less, 3 mol% or less, or 1 mol% or less based on 100 mol% of the dicarboxylic acid component.

[0034] The above diol component includes a linear alkanediol having 3 to 6 carbon atoms. The linear C3-C6 alkanediol may be, for example, at least one selected from the group consisting of propanediol, butanediol, pentanediol, and hexanediol. Specifically, the linear C3-C6 alkanediol may be a compound having hydroxyl groups at both terminals of a linear alkane. More specifically, the linear C3-C6 alkanediol may be, for example, at least one selected from the group consisting of 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. As a specific example, the linear C3-C6 alkanediol may be at least one selected from the group consisting of 1,3-propanediol, 1,4-butanediol, and 1,5-pentanediol. As another specific example, the linear C3-C6 alkanediol may be at least one selected from 1,3-propanediol and 1,4-butanediol. As another specific example, the linear C3-C6 alkanediol may be 1,4-butanediol.

[0035] The content of the linear C3-C6 alkanediol may be, for example, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, 85 mol% or more, 90 mol% or more, or 95 mol% or more, based on 100 mol% of the diol component, and may also be 100 mol% or less, 99 mol% or less, or 98 mol% or less. In one specific example, the content of the linear C3-C6 alkanediol may be 50 mol% or more, based on 100 mol% of the diol component. More specifically, the diol component may include 50 mol% to 100 mol%, 80 mol% to 100 mol%, 80 mol% to 99 mol%, or 90 mol% to 99 mol% of the linear C3-C6 alkanediol.

[0036] According to another embodiment of the present invention, the diol component may additionally include polyether glycol.

[0037] The polyether glycol may have, for example, 2 or more, 3 or more, or 4 or more carbon atoms in the repeating unit, and may also have 10 or less, 8 or less, or 6 or less, and specifically, 2 to 8 or 3 to 5.

[0038] In one specific example, the polyether glycol may include polytetramethylene glycol (PTMG).

[0039] In addition, the number average molecular weight of the polyether glycol may be, for example, 200 or more, 250 or more, 300 or more, 400 or more, or 500 or more, and may also be 5000 or less, 3000 or less, 2500 or less, 2000 or less, 1500 or less, or 1000 or less, and specifically, may be 200 to 5000, or 250 to 3000. As is well known, the molecular weight of the compound or the molecular weight of the polymer described herein is a relative mass based on carbon-12 and does not indicate a unit, but may be understood as a molar mass (g / mol) or Dalton (Da) of the same numerical value, if necessary.

[0040] The content of the above polyether glycol may be 0.1 mol% or more, 0.5 mol% or more, 1 mol% or more, 2 mol% or more, or 3 mol% or more, and may also be 20 mol% or less, 15 mol% or less, 10 mol% or less, 8 mol% or less, 6 mol% or less, or 5 mol% or less, based on 100 mol% of the above diol component.

[0041] In one specific example, the content of the polyether glycol may be 0.1 mol% to 50 mol% based on 100 mol% of the diol component. Within the above preferred range, the polyester polymer may be more advantageous in having softness while improving cold resistance, chemical resistance, and elasticity. More specifically, the content of the polyether glycol may be 1 mol% to 30 mol%, 1 mol% to 20 mol%, or 1 mol% to 10 mol% based on 100 mol% of the diol component.

[0042] According to another embodiment of the present invention, the diol component may further comprise an additional diol component other than linear C3-C6 alkanediol and polyether glycol.

[0043] Specifically, the additional diol component may include at least one selected from the group consisting of ethylene glycol, branched C3-C6 alkane diols, cyclohexanedimethanol, neopentyl glycol, and triethylene glycol. For example, the additional diol component may include at least one selected from the group consisting of ethylene glycol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, and 1,4-cyclohexanedimethanol.

[0044] The content of the above additional diol component may be 0.1 mol% or more, 0.5 mol% or more, 1 mol% or more, or 2 mol% or more, and may also be 15 mol% or less, 10 mol% or less, 8 mol% or less, 6 mol% or less, or 5 mol% or less, based on 100 mol% of the above diol component.

[0045]

[0046] Characteristics of polyester polymers

[0047] The polyester polymer may have an intrinsic viscosity (IV) of, for example, 0.5 dl / g or more, 0.55 dl / g or more, 0.6 dl / g or more, 0.65 dl / g or more, 0.7 dl / g or more, 0.75 dl / g or more, or 0.8 dl / g or more, and may also be 1.3 dl / g or less, 1.2 dl / g or less, 1.15 dl / g or less, or 1.1 or less. For example, the intrinsic viscosity (IV) of the polyester polymer may be 0.5 dl / g to 1.3 dl / g, 0.55 dl / g to 1.2 dl / g, or 0.6 dl / g to 1.15 dl / g.

[0048] The polyester polymer may have a specific gravity of, for example, 1.2 or more, 1.21 or more, or 1.22 or more, and may also have a specific gravity of 1.7 or less, 1.5 or less, or 1.3 or less, and specifically, may be from 1.2 to 1.5, or from 1.21 to 1.3.

[0049] The polyester polymer may have a Shore D hardness of, for example, 20 or more, 25 or more, 30 or more, or 35 or more, and may also have a Shore D hardness of 95 or less, 90 or less, 85 or less, or 80 or less. Specifically, the Shore D hardness of the polyester polymer may be 23 to 93, 25 to 81, 30 to 90, 32 to 78, or 35 to 75. Shore D hardness indicates the degree of hardness and is a measure of softness, so when the Shore D hardness is within the above range, it can be considered to have appropriate softness.

[0050] In one embodiment, the polyester polymer may have a specific gravity of 1.2 or greater and a Shore D hardness of 20 to 95.

[0051] The above polyester polymer has a tensile strength of, for example, 100 kgf / cm. 2 Above, 200 kgf / cm 2 Above, 300 kgf / cm 2 Above, 335 kgf / cm 2 or more than 350 kgf / cm 2 It can be more than 700 kgf / cm 2 Below 600 kgf / cm 2 Below 500 kgf / cm 2 or less, or 450 kgf / cm 2 It may be less than or equal to. For example, the tensile strength of the polyester polymer may be 150 kgf / cm. 2 Up to 700 kgf / cm 2 , 150 kgf / cm 2 Up to 300 kgf / cm 2 , 300 kgf / cm 2 Up to 600 kgf / cm 2 , 335 kgf / cm 2 Up to 600 kgf / cm 2 , 350 kgf / cm 2 Up to 600 kgf / cm 2 , or 300 kgf / cm 2Up to 450 kgf / cm 2 The above tensile strength may be the maximum stress that can be withstood when the polyester polymer is made into a specimen during tension.

[0052] The polyester polymer may have a tensile elongation of, for example, 200% or more, 300% or more, 400% or more, 500% or more, 600% or more, 700% or more, or 800% or more, and may also have a tensile elongation of 3000% or less, 2000% or less, 1600% or less, 1500% or less, 1400% or less, 1300% or less, or 1200% or less. For example, the tensile elongation of the polyester polymer may be 200% to 3,000%, 200% to 1600%, 200% to 1200%, or 800% to 1600%. The tensile elongation may be the maximum elongation when the polyester polymer is made into a specimen and stretched to break.

[0053] The above polyester polymer may have a melting temperature (Tm) measured by differential scanning calorimetry (DSC) of, for example, 100°C or higher, 120°C or higher, 130°C or higher, 140°C or higher, or 150°C or higher, and may also have a melting temperature (Tm) of 200°C or lower, 180°C or lower, 170°C or lower, or 160°C or lower. In one embodiment, the polyester polymer may have a melting temperature (Tm) measured by differential scanning calorimetry (DSC) of 130°C to 190°C. Within the above preferred range, the polyester polymer may be more advantageous in terms of softness and cold resistance. In addition, when the polyester polymer is amorphous or has very low crystallinity, it may be difficult to measure the melting temperature (Tm) by differential scanning calorimetry (DSC). Accordingly, the melting temperature (Tm) of the polyester polymer may not be measured by differential scanning calorimetry (DSC) or may be measured as 130°C to 190°C.

[0054] The polyester polymer may have a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of, for example, -50°C or higher, -40°C or higher, -30°C or higher, -20°C or higher, -10°C or higher, or 0°C or higher, and may also have a glass transition temperature (Tg) of 30°C or lower, 25°C or lower, 20°C or lower, 15°C or lower, 10°C or lower, 5°C or lower, 0°C or lower, -5°C or lower, -10°C or lower, -15°C or lower, or -20°C or lower. Specifically, the polyester polymer may have a glass transition temperature (Tg) measured by differential scanning calorimetry (DSC) of -50°C to 30°C, -40°C to 25°C, -40°C to 0°C, or -20°C to 25°C. In one specific example, the polyester polymer may have a glass transition temperature of -40°C to 25°C as measured by differential scanning calorimetry (DSC). The glass transition temperature is the temperature at which some polymer chains begin to move and is related to softness. When the glass transition temperature is within the above range, the softness is excellent even at low temperatures, and cold resistance can be further improved.

[0055] The heat of fusion of the polyester polymer may be, for example, 5 J / g or more, 10 J / g or more, 15 J / g or more, or 20 J / g or more, and may also be 40 J / g or less, 35 J / g or less, or 30 J / g or less. Specifically, the heat of fusion of the polyester polymer may be 10 J / g to 50 J / g, or 20 J / g to 40 J / g. The heat of fusion is the amount of heat applied when a crystal of a crystalline resin melts, and is related to the size of the crystal. When the heat of fusion is within the above range, the crystallinity of the polyester polymer is controlled, so that heat resistance, etc. can be improved.

[0056] In one embodiment, the polyester polymer may have a glass transition temperature of -40°C to 25°C and a heat of fusion of 10 J / g to 50 J / g as measured by differential scanning calorimetry (DSC). Within the preferred range, the polyester polymer may be more advantageous in terms of softness and cold resistance. In addition, when the polyester polymer is amorphous or has very low crystallinity, it may be difficult to measure the heat of fusion. Therefore, the polyester polymer may have a glass transition temperature of -40°C to 25°C as measured by differential scanning calorimetry (DSC), and a heat of fusion that is not measured or is measured as 10 J / g to 50 J / g.

[0057] The above polyester polymer may have a crystallization temperature (Tc) measured by a differential scanning calorimeter (DSC) of, for example, 20°C or higher, 25°C or higher, 30°C or higher, 35°C or higher, or 40°C or higher, and may also have a crystallization temperature of 70°C or lower, 65°C or lower, 60°C or lower, 55°C or lower, 50°C or lower, or 45°C or lower. Specifically, the polyester polymer may have a crystallization temperature (Tc) measured by a differential scanning calorimeter (DSC) of 30°C to 60°C. In addition, when the polyester polymer is amorphous or has very low crystallinity, it may be difficult to measure the crystallization temperature (Tc) by a differential scanning calorimeter (DSC). Accordingly, the polyester polymer may have a crystallization temperature (Tc) that is not measured by differential scanning calorimetry (DSC) or may be measured as 30°C to 60°C.

[0058] The above polyester polymer may have a Vicat softening temperature of 80°C or higher, 90°C or higher, 100°C or higher, 110°C or higher, 120°C or higher, or 130°C or higher, and may also have a Vicat softening temperature of 160°C or lower, 150°C or lower, 140°C or lower, or 130°C or lower. The Vicat softening temperature may be, for example, a temperature of 100°C or lower when the cross section is 1 mm. 2The Vicat softening temperature may be measured by measuring the temperature at which a flat-tipped needle of a circular or square shape penetrates the specimen to a depth of 1 mm under a constant load. In addition, the Vicat softening temperature may be measured according to ASTM D1525.

[0059] In one embodiment, the polyester polymer may have a Vicat softening temperature of 100°C to 150°C as measured according to ASTM D1525. Within this preferred range, the polyester polymer may be more advantageous in improving cold resistance, chemical resistance, and elasticity while maintaining softness.

[0060] In addition, the polyester polymer may have an injection molding shrinkage rate below a certain level. For example, the polyester polymer may have an injection molding shrinkage of 7,200 mm. 3 After filling a mold having a cavity of a certain volume by injection at a temperature of 170°C to 230°C, the volume of the shrunken specimen is measured by cooling to 7°C, and the shrinkage ratio can be calculated according to the following equation.

[0061] Injection molding shrinkage (%) = [(cavity volume - shrunken specimen volume) / cavity volume] x 100.

[0062] For example, the shrinkage rate of the injection-molded specimen according to the above formula may be 15% or less, 10% or less, or 5% or less. More specifically, the shrinkage rate of the injection-molded specimen according to the above formula may be 4% or less. Within the above preferred range, the cold resistance and elasticity of the polyester polymer may be more advantageously improved. In a specific example, the shrinkage rate calculated according to the above formula may be 0% to 4%, or 1% to 4%.

[0063] The above polyester polymer may have softness at room temperature.

[0064] The polyester polymer may have a storage modulus measured at 25°C using a dynamic mechanical analyzer (DMA) of, for example, 100 MPa or more, 300 MPa or more, 500 MPa or more, 700 MPa or more, 900 MPa or more, or 1100 MPa or more, and may also have a storage modulus of 1900 MPa or less, 1700 MPa or less, 1500 MPa or less, 1300 MPa or less, 1100 MPa or less, or 900 MPa or less. As a specific example, the polyester polymer may have a storage modulus measured at 25°C using DMA of 100 MPa to 1500 MPa, 100 MPa to 1000 MPa, or 600 MPa to 1500 MPa.

[0065] In addition, the polyester polymer may have a difference (△E') between a storage modulus measured at 25°C (E'@25°C) and a storage modulus measured at -10°C (E'@-10°C) using a dynamic mechanical analyzer (DMA) of, for example, 300 MPa or more, 400 MPa or more, 500 MPa or more, 600 MPa or more, or 700 MPa or more, and may also be 1700 MPa or less, 1500 MPa or less, 1300 MPa or less, 1100 MPa or less, or 900 MPa or less, and specifically, may be 300 MPa to 1700 MPa, 400 MPa to 1500 MPa, 500 MPa to 1000 MPa, or 1000 MPa to 1300 MPa.

[0066] In addition, the polyester polymer may have a difference (△E') between a storage modulus measured at 25°C (E'@25°C) and a storage modulus measured at -20°C (E'@-20°C) using a dynamic mechanical analyzer (DMA) of, for example, 200 MPa or more, 300 MPa or more, 400 MPa or more, 500 MPa or more, 600 MPa or more, or 700 MPa or more, and may also be 1600 MPa or less, 1500 MPa or less, 1400 MPa or less, 1300 MPa or less, 1100 MPa or less, or 900 MPa or less, and specifically, may be 200 MPa to 1600 MPa, 300 MPa to 1500 MPa, 300 MPa to 900 MPa, or 700 MPa to 1600 MPa.

[0067] Meanwhile, in general, the lower the temperature, the higher the storage modulus, and the softness at room temperature can be estimated by measuring the temperature at a specific storage modulus. For example, the temperature at which the polyester polymer has a storage modulus (E') of 1000 MPa measured using a dynamic mechanical analyzer (DMA) may be -30°C or higher, -20°C or higher, -10°C or higher, 0°C or higher, 5°C or higher, 10°C or higher, 15°C or higher, or 20°C or higher, and may also be 40°C or lower, 35°C or lower, 30°C or lower, or 25°C or lower. Specifically, the temperature at which the polyester polymer has a storage modulus (E') of 1000 MPa measured using a dynamic mechanical analyzer (DMA) may be -20°C to 40°C, -20°C to 20°C, or 20°C to 40°C.

[0068] Tanδ (tan delta) is defined as the loss modulus (E') divided by the storage modulus (E') (i.e. tanδ = E'' / E'), and can be an important indicator of the softness of a polymer, like the glass transition temperature. The loss modulus represents viscous behavior and indicates the degree to which energy is lost, while the storage modulus represents elastic behavior and indicates the degree to which energy is stored.

[0069] Tanδ can be measured, for example, using a dynamic mechanical analysis (DMA) device. First, a specimen is cut to an appropriate size and mounted in a DMA clamp or holder. The specimen is then subjected to cyclic stress or strain while being heated or cooled. The phase difference between the cyclic stress and the response is measured in the DMA, from which the specimen's loss modulus and storage modulus are derived, and tanδ is then calculated.

[0070] Specifically, the heat-shrinkable film is cut in the main shrinkage direction, mounted on a tensile clamp, and a tanδ curve can be obtained using a dynamic mechanical analyzer (DMA) under a temperature increase condition of 3℃ / min from 30℃ to 150℃ at a frequency of 1 Hz. In one embodiment, the maximum peak temperature in the tanδ curve may be -10℃ or higher, -5℃ or higher, 0℃ or higher, 10℃ or higher, 20℃ or higher, or 25℃ or higher, and may also be 60℃ or lower, 50℃ or lower, 40℃ or lower, or 30℃ or lower, and specifically, may be -10℃ to 60℃, -5℃ to 30℃, or 25℃ to 50℃. In addition, the onset temperature of the peak in the tanδ curve may be -50°C or higher, -40°C or higher, -30°C or higher, -20°C or higher, -10°C or higher, 0°C or higher, or 10°C or higher, and may also be 30°C or lower, 25°C or lower, 20°C or lower, 15°C or lower, or 10°C or lower, and specifically may be -50°C to 30°C, -40°C to 25°C, -40°C to 10°C, or 10°C to 25°C.

[0071] In one embodiment, the polyester polymer may have an onset temperature of a peak in a tanδ curve obtained by measuring with a dynamic mechanical analyzer (DMA) of -40°C to 25°C. Within the preferred range, the polyester polymer may be more advantageous in improving cold resistance, chemical resistance, and elasticity while maintaining softness.

[0072]

[0073] Method for producing polyester polymer

[0074] The method for producing a polyester polymer according to the present invention includes a step of producing a polyester polymer through a polymerization reaction of a dicarboxylic acid component and a diol component.

[0075] The polyester polymer manufactured by the above method has substantially the same composition and properties as the polyester polymer described above. Preferably, the raw materials and process conditions can be adjusted so that the polyester polymer finally manufactured by the above method satisfies the composition and properties described above.

[0076] According to one embodiment, the step of preparing the polyester polymer includes the steps of mixing a dicarboxylic acid component and a diol component; subjecting the mixture to an esterification or transesterification reaction; and subjecting the product of the esterification or transesterification reaction to a polycondensation reaction.

[0077] First, mix the dicarboxylic acid component and the diol component.

[0078] The dicarboxylic acid component includes a first dicarboxylic acid component, a second dicarboxylic acid component, or a combination thereof. Specifically, the first dicarboxylic acid component, the second dicarboxylic acid component, or a combination thereof is mixed with the diol component to produce a mixture. The descriptions of the first dicarboxylic acid component, the second dicarboxylic acid component, and the diol component are as described above.

[0079] Specifically, the first dicarboxylic acid component includes terephthalic acid, dimethyl terephthalate, or a combination thereof, the second dicarboxylic acid component includes cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof, and the content of the second dicarboxylic acid component is 30 mol% or more based on 100 mol% of the dicarboxylic acid component.

[0080] Additionally, the above diol component includes a linear C3-C6 alkane diol and may additionally include polytetramethylene glycol (PTMG).

[0081] According to another embodiment, one or more additives selected from the group consisting of a coloring agent, a crystallizing agent, an oxidation stabilizer, and a branching agent may be additionally added to the mixture of the first dicarboxylic acid component, the second dicarboxylic acid component, and the diol component.

[0082] The above coloring agent is an additive for improving the color characteristics of the polyester polymer. As long as the coloring agent does not impede the effects of the present invention, any commonly used coloring agent, such as cobalt acetate or cobalt propionate, may be used.

[0083] Specifically, the coloring agent may be cobalt acetate, cobalt propionate, anthraquionone-based compound, perinone-based compound, azo-based compound, methine-based compound, etc., and commercially available products include toners such as Clarient's Polysynthren Blue RLS or Clarient's Solvaperm Red BB.

[0084] In addition, the polyester polymer may contain the coloring agent in an amount of 0.1 ppm to 30 ppm based on the total weight of the polyester polymer. For example, the coloring agent may be added in an amount of 0.2 ppm to 30 ppm, 0.5 ppm to 25 ppm, 0.6 ppm to 23 ppm, or 0.8 ppm to 20 ppm based on the total weight of the mixture. By satisfying the content of the coloring agent within the above range, the color characteristics of the polyester polymer can be sufficiently improved without deteriorating the mechanical properties.

[0085] The above crystallizer may include at least one selected from the group consisting of a crystal nucleating agent, an ultraviolet absorber, a polyolefin resin, a polyamide resin, a polyester resin, a polyester elastomer resin, and a polyalkylene resin.

[0086] In addition, the polyester polymer may contain the crystallizer at 0.1 ppm to 20 wt% based on the total weight of the polyester polymer. For example, the crystallizer may be added at 0.2 ppm to 20 wt%, 0.5 ppm to 15 wt%, 1 ppm to 10 wt%, 2 ppm to 8 wt%, 3 ppm to 5 wt%, or 4 ppm to 1 wt% based on the total weight of the mixture. By satisfying the content of the crystallizer within the above range, mechanical properties such as heat resistance and impact strength can be improved.

[0087] The above oxidation stabilizer may include at least one selected from the group consisting of phosphorus-based, hindered phenol-based, phosphite-based, and thioether-based.

[0088] In addition, the polyester polymer may contain the oxidation stabilizer in an amount of 50 ppm to 2,500 ppm based on the total weight of the polyester polymer. For example, the oxidation stabilizer may be added in an amount of 50 ppm to 2,300 ppm, 60 ppm to 2,200 ppm, 80 ppm to 2,100 ppm, 100 ppm to 2,000 ppm, or 100 ppm to 1,500 ppm based on the total weight of the mixture. By satisfying the content of the oxidation stabilizer within the above range, not only can a decrease in intrinsic viscosity that may occur during subsequent processing or other processes be effectively prevented, but also a decrease in physical properties such as impact strength can be prevented.

[0089] The above-mentioned branching agent may include at least one selected from the group consisting of trimellitic anhydride, trimellitic propane, trimellitic acid, and glycerol.

[0090] In addition, the polyester polymer may contain the branching agent in an amount of 10 ppm to 5000 ppm based on the total weight of the polyester polymer. For example, the branching agent may be added in an amount of 20 ppm to 4000 ppm or 30 ppm to 3000 ppm based on the total weight of the mixture. By satisfying the content of the branching agent within the above range, the intrinsic viscosity can be more effectively controlled within a specific range, thereby improving physical properties such as impact strength.

[0091] Afterwards, the mixture is subjected to an esterification or transesterification reaction.

[0092] Specifically, a mixture of the first dicarboxylic acid component, the second dicarboxylic acid component, and the diol component is subjected to an esterification or ester exchange reaction.

[0093] The above esterification or transesterification reaction is at atmospheric pressure or 0.1 kg / cm compared to atmospheric pressure. 2 3.0 kg / cm 2 It can be performed for 2 to 12 hours under high pressure conditions and temperature conditions of 245°C to 275°C.

[0094] Specifically, the pressurized state is 0.1 kg / cm compared to normal pressure. 2 3.0 kg / cm 2 , 0.2 kg / cm 2 2.5 kg / cm 2 or 0.3 kg / cm 2 2.0 kg / cm 2 It can be as high as that. In addition, the esterification or ester exchange reaction can be performed at a temperature condition of 150°C to 275°C, 155°C to 275°C, or 160°C to 270°C for 2 to 12 hours, 2 to 11 hours, or 2.5 to 10 hours.

[0095] For example, the esterification or transesterification reaction is carried out at 0.1 kg / cm2 at normal pressure or at normal pressure. 2 3.0 kg / cm 2 The temperature can be increased from room temperature to 150°C to 275°C or from 155°C to 270°C over 30 to 110 minutes or 30 to 100 minutes under high pressure, maintained for 0.5 to 3 hours or 0.5 to 2.5 hours, and then continuously or stepwise increased from room temperature to 150°C to 275°C or from 155°C to 270°C over 2 to 12 hours.

[0096] When the above esterification or ester exchange reaction is completed, the pressure of the pressurized reactor can be lowered to room temperature and the following polycondensation reaction can be performed.

[0097] Finally, the product of the above esterification or transesterification reaction is subjected to a polycondensation reaction.

[0098] The polycondensation reaction may be carried out under conditions of a pressure of 0.00001 mmHg to 400 mmHg and a temperature of 240°C to 300°C for 1 to 12 hours. For example, the polycondensation reaction may be carried out under conditions of a pressure of 0.00001 mmHg to 200 mmHg, 0.0001 mmHg to 100 mmHg, 0.001 mmHg to 50 mmHg, 0.002 mmHg to 10 mmHg, 0.005 mmHg to 3 mmHg, 0.01 mmHg to 1.5 mmHg, or 0.01 mmHg to 1.2 mmHg, and a temperature of 240°C to 300°C or 245°C to 295°C for 1 to 12 hours or 1 to 10 hours.

[0099] For example, the polycondensation reaction may be performed by reducing the pressure of the product of the esterification or transesterification reaction to 4.0 mmHg to 6.0 mmHg or 4.5 mmHg to 5.5 mmHg over 20 to 40 minutes or 25 to 35 minutes, and then heating the product to 240°C to 300°C or 245°C to 295°C over 0.5 to 2 hours or 0.7 to 1.2 hours, and then maintaining the pressure at 0.01 mmHg to 400 mmHg.

[0100] At the beginning of the polycondensation reaction, the stirring speed is set to high, and as the polycondensation reaction progresses, the stirring force becomes weak due to the increase in the viscosity of the reactants, or the temperature of the reactants rises above the set temperature, the stirring speed can be appropriately adjusted accordingly.

[0101] The intrinsic viscosity (IV) of the melt produced by the polycondensation reaction may be 0.5 dl / g to 1.3 dl / g. For example, the polycondensation reaction may be performed until the intrinsic viscosity (IV) of the melt produced by the polycondensation reaction becomes 0.5 dl / g to 1.2 dl / g, 0.6 dl / g to 1.15 dl / g, or 0.7 dl / g to 1.2 dl / g.

[0102] Additionally, a catalyst and / or stabilizer may be additionally added in the esterification or ester exchange reaction and the condensation polymerization reaction.

[0103] For example, the catalyst in the esterification or transesterification reaction may be a methylate of sodium or magnesium; an acetate, borate, fatty acid salt, or carbonate of Zn, Cd, Mn, Co, Ca, Ba, etc.; an oxide of metal Mg; an oxide of Pb, Zn, Sb, Ge, etc.

[0104] In addition, the polycondensation reaction catalyst may be, for example, a titanium-based catalyst such as tetraethyl titanate, acetyltripropyl titanate, tetrapropyl titanate, tetrabutyl titanate, polybutyl titanate, 2-ethylhexyl titanate, octylene glycol titanate, lactate titanate, triethanolamine titanate, acetyl acetonate titanate, ethyl acetoacetic ester titanate, isostearyl titanate, titanium dioxide, titanium dioxide / silicon dioxide copolymer, titanium dioxide / zirconium dioxide copolymer, etc.; a germanium-based catalyst such as germanium dioxide and copolymers using the same; or a tin-based catalyst such as monobutyl tin oxide, dibutyl tin oxide, monobutyl hydroxy tin oxide, etc.

[0105] Additionally, the stabilizer may be a phosphorus compound such as phosphoric acid, trimethyl phosphate, or triethyl phosphate, but is not limited thereto.

[0106] The stabilizer may be added in an amount of 10 ppm to 2,500 ppm based on the total weight of the polycondensation reactant. For example, the stabilizer may be added in an amount of 150 ppm to 2,300 ppm, 200 ppm to 2,000 ppm, 300 ppm to 1,500 ppm, 50 ppm to 400 ppm, 70 ppm to 350 ppm, or 100 ppm to 300 ppm based on the total weight of the polycondensation reactant.

[0107] The polyester polymer according to the present invention can be processed into various products including sheets and films by being applied to a calendaring or T-die process, and can replace conventional soft PVC to improve heat resistance and improve roll release properties in a calendaring process.

[0108]

[0109] [Example]

[0110] The above contents are explained in more detail with the following examples. However, the following examples are only for illustrating the present invention, and the scope of the examples is not limited to these examples.

[0111]

[0112] Reference Example 1: Preparation of polyester polymer

[0113]

[0114] (1) Esterification reaction

[0115] In a 10 L reactor connected to a column and a condenser that can be cooled by water, 761 g (4.58 mol) of terephthalic acid (TPA), 2,141 g (10.69 mol) of dimethylcyclohexanedicarboxylate (DMCD), and 1,896 g (30.54 mol) of ethylene glycol (EG) were charged. At this time, G / A (total diol / total diacid, molar ratio of diol component to dicarboxylic acid component) was 2.0.

[0116] Afterwards, 0.853 g of tetrabutyl titanate (TBT) as a catalyst, 0.235 g of phosphoric acid as an oxidation stabilizer, and 1.47 g of trimellitic anhydride as a branching agent were added and stirred.

[0117] Afterwards, nitrogen was injected into the reactor containing the mixture so that the pressure of the reactor was 1.0 kgf / cm compared to the atmospheric pressure. 2The reactor was pressurized to a high pressure (absolute pressure: 1495.6 mmHg). Then, the temperature of the reactor was increased from room temperature to 200°C over 60 minutes, maintained at 200°C for 2 hours, and then increased again to 245°C over 5 hours. Afterwards, the esterification reaction was carried out at 245°C for 0.5 hours. During this process, by-products were discharged through the column and condenser. When the esterification reaction was completed, the nitrogen inside the pressurized reactor was purged to the outside to lower the pressure of the reactor to ambient pressure, and the product of the esterification reaction inside the reactor was transferred to a 7 L reactor capable of vacuum reaction.

[0118]

[0119] (2) Condensation polymerization reaction

[0120] Afterwards, the pressure of the reactor containing the product of the esterification reaction was reduced from atmospheric pressure to 5.0 Torr (absolute pressure: 5 mmHg) over 30 minutes, and at the same time, the temperature of the reactor was increased to 270°C over 1 hour, and the pressure of the reactor was maintained at 1.0 Torr (absolute pressure: 1.0 mmHg) or less to carry out the polycondensation reaction. At this time, the stirring speed was set to be fast at the beginning of the polycondensation reaction, but as the polycondensation reaction progressed, the stirring force weakened due to the increase in the viscosity of the reactants, or when the temperature of the reactants rose above the set temperature, the stirring speed was appropriately adjusted accordingly.

[0121]

[0122] Example 1: Preparation of polyester polymer

[0123]

[0124] (1) Ester exchange reaction

[0125] In a 10 L reactor connected to a column and a condenser that could be cooled by water, 2,212 g (11.05 mol) of dimethylcyclohexanedicarboxylate (DMCD) and 1,311 g (14.92 mol) of 1,4-butanediol (1,4-BD) were charged. At this time, G / A (total diol / total dicarboxylate, molar ratio of diol component to dicarboxylate component) was 1.35.

[0126] Afterwards, 0.853 g of tetrabutyl titanate (TBT) as a catalyst, 0.235 g of phosphoric acid as an oxidation stabilizer, and 1.47 g of trimellitic anhydride as a branching agent were added and stirred.

[0127] Afterwards, the temperature of the reactor was increased from room temperature to 200°C over 30 minutes under atmospheric pressure, maintained at 200°C for 1 hour, and then increased again to 210°C over 30 minutes. Afterwards, the transesterification reaction was performed at 210°C for 1 hour. During this process, by-products were discharged through the column and condenser. When the transesterification reaction was completed, the product of the transesterification reaction in the reactor was transferred to a 7 L reactor capable of vacuum reaction.

[0128]

[0129] (2) Condensation polymerization reaction

[0130] Afterwards, the pressure of the reactor containing the product of the transesterification reaction was reduced from atmospheric pressure to 5.0 Torr (absolute pressure: 5 mmHg) over 30 minutes, and at the same time, the temperature of the reactor was increased to 245°C over 1 hour, and the pressure of the reactor was maintained at 1.0 Torr (absolute pressure: 1.0 mmHg) or less to perform the polycondensation reaction. At this time, the stirring speed was set to be fast in the initial stage of the polycondensation reaction, but as the polycondensation reaction progressed, the stirring force weakened due to the increase in the viscosity of the reactants, or when the temperature of the reactants rose above the set temperature, the stirring speed was appropriately adjusted accordingly.

[0131]

[0132] Examples 2 to 4: Preparation of polyester polymers

[0133]

[0134] A polyester polymer was manufactured in the same manner as in Example 1, except that the components and contents were different as shown in Table 1 below.

[0135]

[0136] Example 5: Preparation of polyester polymer

[0137]

[0138] (1) Ester exchange reaction

[0139] In a 10 L reactor connected to a column and a water-cooled condenser, 1,209 g (6.23 mol) of dimethyl terephthalate (DMT), 831 g (4.15 mol) of dimethylcyclohexanedicarboxylate (DMCD), 1,244 g (13.81 mol) of 1,4-butanediol (1,4-BD), and 208 g (0.21 mol) of polytetramethylene glycol (PTMG) were charged. At this time, G / A (total diol / total dicarboxylate, molar ratio of diol component to dicarboxylate component) was 1.35.

[0140] Afterwards, 0.853 g of tetrabutyl titanate (TBT) as a catalyst, 0.235 g of phosphoric acid as an oxidation stabilizer, and 1.47 g of trimellitic anhydride as a branching agent were added and stirred.

[0141] Afterwards, the temperature of the reactor was increased from room temperature to 200°C over 30 minutes under atmospheric pressure, maintained at 200°C for 1 hour, and then increased again to 210°C over 30 minutes. Afterwards, the transesterification reaction was performed at 210°C for 1 hour. During this process, by-products were discharged through the column and condenser. When the transesterification reaction was completed, the product of the transesterification reaction in the reactor was transferred to a 7 L reactor capable of vacuum reaction.

[0142]

[0143] (2) Condensation polymerization reaction

[0144] Afterwards, the pressure of the reactor containing the product of the transesterification reaction was reduced from atmospheric pressure to 5.0 Torr (absolute pressure: 5 mmHg) over 30 minutes, and at the same time, the temperature of the reactor was increased to 245°C over 1 hour, and the pressure of the reactor was maintained at 1.0 Torr (absolute pressure: 1.0 mmHg) or less to perform the polycondensation reaction. At this time, the stirring speed was set to be fast in the initial stage of the polycondensation reaction, but as the polycondensation reaction progressed, the stirring force weakened due to the increase in the viscosity of the reactants, or when the temperature of the reactants rose above the set temperature, the stirring speed was appropriately adjusted accordingly.

[0145]

[0146] Examples 6 to 8: Preparation of polyester polymers

[0147]

[0148] A polyester polymer was manufactured in the same manner as in Example 5, except that the components and contents were different as shown in Table 2 below.

[0149]

[0150] The monomer compositions of the above reference examples and examples are summarized in the table below.

[0151] Monomer Reference Example 1 Example 1 Example 2 Example 3 Example 4 Dicarboxylic acid TPA 30 mol%----DMT--30 mol%60 mol%70 mol%DMCD 70 mol%100 mol%70 mol%40 ​​mol%30 mol%Diol EG 100 mol%----1,4-BD-100 mol%100 mol%100 mol%100 mol%PTMG-----

[0152] Monomer Reference Example 1 Example 5 Example 6 Example 7 Example 8 Dicarboxylic acid TPA 30 mol%----DMT-60 mol% 70 mol% 70 mol% 70 mol% DMCD 70 mol% 40 mol% 30 mol% 30 mol% 30 mol% Diol EG 100 mol%----1,4-BD-98 mol% 98 mol% 96 ​​mol% 94 mol% PTMG-2 mol% 2 mol% 4 mol% 6 mol%

[0153]

[0154] Exam example

[0155] The polyester polymers obtained in the above reference examples and examples were tested as follows.

[0156]

[0157] (1) Intrinsic viscosity (IV)

[0158] After dissolving a polyester polymer in orthochlorophenol (OCP) at 150°C at a concentration of 0.12%, the intrinsic viscosity (IV, dl / g) was measured using a Ubbelrod viscometer in a constant temperature bath at 35°C.

[0159]

[0160] (2) Tg, Tc, Tm and heat of fusion

[0161] For polyester polymers, the glass transition temperature (Tg), crystallization temperature (Tc), melting temperature (Tm), and heat of fusion were measured using differential scanning calorimetry (DSC).

[0162] Specifically, the polyester polymer was processed at 270°C using an injection molding machine to obtain an injection molded flat specimen having a thickness of 6 mm, and then the first scan was obtained by increasing the temperature from -20°C to 280°C at 10°C / min using a differential scanning calorimeter and maintaining it at 280°C for 2 minutes, then decreasing the temperature from 280°C to -20°C at -300°C / min, maintaining it for 15 minutes, and then increasing the temperature from -20°C to 280°C at 10°C / min again to obtain a second scan. The glass transition temperature (Tg), crystallization temperature (Tc), melting temperature (Tm), and heat of fusion were measured from the heat flow curve obtained in the above process.

[0163]

[0164] (3) Specific gravity

[0165] The specific gravity of polyester polymers was measured according to ASTM D 256.

[0166]

[0167] (4) Shore D hardness

[0168] According to ASTM D2240-05, a polyester polymer specimen was injection-molded into a flat specimen with a thickness of 6 mm or more, and then the Shore D hardness was measured.

[0169]

[0170] (5) Tensile strength and tensile elongation

[0171] The tensile strength and tensile elongation of polyester polymers were measured according to ASTM D 638. Specifically, a flat specimen with a thickness of 2 mm was obtained at 170-230℃ using an injection molding machine, and then cut into pieces with a length of 100 mm and a width of 15 mm. The specimen was mounted on an INSTRON universal testing machine (4206-001, manufacturer: UTM) with a chuck spacing of 50 mm and tested at a tensile speed of 50 mm / min. The tensile strength (maximum stress withstood during tension) was measured using a program built into the equipment.

[0172] In addition, the above-mentioned injection molded product was cut into pieces of 100 mm in length and 15 mm in width, and the maximum deformation just before fracture was measured at a speed of 500 mm / min using a universal testing machine (4206-001, manufacturer: UTM) from INSTRON. Then, the tensile elongation (maximum elongation at fracture under tension) was measured by calculating the ratio of the maximum deformation to the initial length.

[0173]

[0174] (6) VICAT softening temperature

[0175] Flat injection molded specimens with a thickness of 6 mm, a width of 12 mm, and a cross-section of 1 mm were manufactured from polyester polymer. 2 The temperature at which a flat-tipped needle penetrated 1 mm deep was measured while maintaining a load of 10 N and pressing the needle against the specimen. The temperature was increased from 20°C to 150°C at a rate of 50°C / min.

[0176]

[0177] (7) Shrinkage of injection molded specimen

[0178] A rectangular cavity with a width of 60 mm, a height of 60 mm, and a thickness of 2 mm (volume of 7,200 mm) 3 ) was prepared. A polyester polymer was injected into the cavity of the mold at a temperature of 170 to 230°C and filled, and then cooled to 7°C to obtain a shrunken specimen. The degree of shrinkage relative to the cavity volume was calculated according to the following equation: Injection specimen shrinkage rate (%) = [(cavity volume - shrunken specimen volume) / cavity volume] x 100.

[0179]

[0180] (8) DMA

[0181] A flat specimen with a thickness of 2 mm was manufactured from a polyester polymer and cut into pieces with a length of 30 mm and a width of 10 mm.

[0182] The specimen was mounted on a tension clamp and a dynamic mechanical analyzer (DMA, TA Q800) was used to obtain a tanδ (tan delta) curve (calculated as tanδ = E' / E", where E' is the storage modulus and E'' is the loss modulus) under a temperature increase condition of 3℃ / min from -50℃ to 50℃ at a frequency of 1 Hz. The tanδ curve was analyzed to obtain the maximum peak temperature and onset temperature.

[0183] In addition, using the same method, the storage modulus (E') at 25℃, -10℃, and -20℃ was measured under the temperature increasing condition of 3℃ / min from -50℃ to 50℃ under the frequency condition of 1 Hz using DMA. In addition, based on this, the difference in storage modulus at 25℃ and -10℃, i.e., △E' (@25℃ vs @-10℃), and the difference in storage modulus at 25℃ and -20℃, i.e., △E' (@25℃ vs @-20℃), were calculated.

[0184] Additionally, the temperature at the point where the storage modulus (E') is 1000 MPa was measured.

[0185]

[0186] (9) Swelling

[0187] Injection-molded bending specimens measuring 3 mm in thickness and 10 mm in width were prepared from polyester polymers and cut to 30 mm in length. The specimens were immersed in a solvent (acetone, toluene, or ethanol) at 25°C for 12 hours. The test results were classified according to the following criteria.

[0188] - Severe swelling: Volume increase due to swelling of 40% or more or partial melting

[0189] - Slight swelling: Volume increase due to swelling of 5% or more but less than 40%

[0190] - No swelling: Volume increase due to swelling is less than 5%

[0191]

[0192] (10) Damage

[0193] Tensile specimens (dog bones) were fabricated from polyester polymers according to ISO standards. To apply stress, the specimens were bent at a 1% curvature in the middle and immersed in a solvent (acetone, toluene, or ethanol) for 3 hours. The test results were classified according to the following criteria.

[0194] - Damaged: Visible deformation, cracks, or breaks

[0195] - No damage: No visible deformation, cracks, or breaks

[0196]

[0197] The results of the above test examples are summarized in the table below.

[0198] Classification Unit Reference Example 1 Example 1 Example 2 Example 3 Example 4 Characteristics Tg℃ 30-7.8 1.89 16 IV dl / g 0.7-1.2 0.7-1.2 0.7-1.2 0.7-1.2 0.7-1.2 Specific gravity 1.26 1.22 1.23 1.24 1.25 Hardness Shore D 60 4 2 4 5 6 0 6 8 Tensile strength kgf / cm 2330230190340500Tensile Elongation%165094010301210720Thermal PropertiesTm℃---150170Heat of FusionJ / g---2529Tc℃---5043VICAT Softening Temperature℃35128.3129.4131.4136.2Shrinkage of Injection Molded Specimen%20-401-4%1-4%1-4%1-4%Cold ResistanceGlass Transition Temperature℃30-7.81.8916tan delta (onset)℃24.6-1.58.614.418.6tan delta (peak)℃36.97.529.43544SoftnessDMA E'(@25℃)MPa1,0666627501,1901,391DMA E'(@-10℃)MPa1,6351,4401,5801,8301,673DMA E'(@-20℃)MPa1,7361,6501,6901,8601,713△E'(@25℃ vs @-10℃)MPa569778830640382△E'(@25℃ vs @-20℃)MPa670988940670322E'=1000MPaTemperature℃25.9-3.319.227.633.7HardnessShore D6042456068Chemical ResistanceSwellingSevereNoneNoneNoneDamageNoneNoneNoneNone

[0199] Classification Unit Reference Example 1 Example 5 Example 6 Example 7 Example 8 Characteristics Tg℃ 300-2-16-33 IV dl / g 0.7-1.2 0.7-1.2 0.7-1.2 0.7-1.2 0.7-1.2 Specific gravity 1.26 1.21 1.23 1.22 1.19 Hardness Shore D 6 0 5 2 5 3 5 0 4 8 Tensile strength kgf / cm 2330425440480450Tensile Elongation%165081572011001200Thermal PropertiesTm℃-146166160155Heat of FusionJ / g-25342429Tc℃-38---VICAT Softening Temperature℃35113.1133.9123120Shrinkage of Injection Molding Specimen%20-402%Less than 2%Less than 2%Less than 2%Less than 2%Cold ResistanceGlass Transition Temperature℃300-2-16-33tan delta (onset)℃24.69.8-13.2-26.6-33.8tan delta (peak)℃36.922.420.67.6-3.2SoftnessDMA E'(@25℃)MPa1,066447547299193DMA E'(@-10℃)MPa1,635167318411331716DMA E'(@-20℃)MPa1,7361790199517451146△E' (@25℃ vs @-10℃)MPa5691,2261,2941,032523△E' (@25℃ vs @-20℃)MPa6701,3431,4481,446953E'=1000MPaTemperature℃25.910.812.4-3-16.8HardnessShore D6052535048Chemical ResistanceSwellingSevereNoneNoneNoneDamageSlightNoneNoneNoneNone

[0200]

[0201] As shown in Tables 3 and 4 above, it can be confirmed that the polyester polymer of the example according to the present invention contains dimethylcyclohexanedicarboxylate as a dicarboxylic acid component in an amount of 30 mol% or more and linear C3-C6 alkane diol as a diol component, thereby having improved cold resistance, chemical resistance, and elasticity while maintaining softness.

Claims

Contains a residue of a dicarboxylic acid component and a residue of a diol component, The above dicarboxylic acid component comprises a combination of a first dicarboxylic acid component and a second dicarboxylic acid component, or a second dicarboxylic acid component, The first dicarboxylic acid component comprises terephthalic acid, dimethyl terephthalate, or a combination thereof, The second dicarboxylic acid component comprises cyclohexanedicarboxylic acid, dimethylcyclohexanedicarboxylate, or a combination thereof, The content of the second dicarboxylic acid component is 30 mol% or more based on 100 mol% of the dicarboxylic acid component, The above diol component is a polyester polymer containing a linear C3-C6 alkanediol. In the first paragraph, A polyester polymer in which the content of the second dicarboxylic acid component is 50 mol% or more based on 100 mol% of the dicarboxylic acid component. In the first paragraph, A polyester polymer wherein the second dicarboxylic acid component comprises dimethylcyclohexanedicarboxylate. In the first paragraph, The above dicarboxylic acid component additionally includes a third dicarboxylic acid component, A polyester polymer, wherein the third dicarboxylic acid component comprises at least one selected from the group consisting of succinic acid, adipic acid, sebacic acid, azelaic acid, dodecanoic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, dimethyl isophthalate, diethyl isophthalate, and dibutyl isophthalate. In the first paragraph, A polyester polymer having a content of the linear C3-C6 alkanediol of 50 mol% or more based on 100 mol% of the diol component. In the first paragraph, The above diol component is a polyester polymer additionally containing polyether glycol. In paragraph 6, The above polyether glycol is a polyester polymer containing polytetramethylene glycol (PTMG). In paragraph 6, A polyester polymer having a content of the polyether glycol of 0.1 mol% to 50 mol% based on 100 mol% of the diol component. In the first paragraph, The above polyester polymer is a polyester polymer having a specific gravity of 1.2 or more and a Shore D hardness of 20 to 95. In the first paragraph, The above polyester polymer is a polyester polymer whose melting temperature (Tm) is not measured by differential scanning calorimetry (DSC) or is measured as 130°C to 190°C. In the first paragraph, The polyester polymer has a glass transition temperature of -40°C to 25°C as measured by differential scanning calorimetry (DSC), and a heat of fusion of no measurement or 10 J / g to 50 J / g. In the first paragraph, The above polyester polymer is a polyester polymer having a Vicat softening temperature of 100°C to 150°C as measured according to ASTM D1525. In the first paragraph, The above polyester polymer is 7,200 mm 3 A polyester polymer having an injection molding shrinkage rate of 4% or less according to the following formula when the volume of a shrinkage specimen is measured by filling the mold with a cavity of a volume at a temperature of 170°C to 230°C and then cooling to 7°C: Injection molding shrinkage (%) = [(cavity volume - shrunken specimen volume) / cavity volume] x 100. In the first paragraph, The above polyester polymer is a polyester polymer having a peak onset temperature of -40°C to 25°C in a tanδ curve obtained by measuring with a dynamic mechanical analyzer (DMA).