Polyester copolymer comprising recycled raw materials

Abstract

The present invention relates to a polyester copolymer having excellent physical properties and biodegradability while having a high content of recycled raw materials. Specifically, the present invention relates to a polyester copolymer, which comprises a repeating unit derived from recycled raw materials, repeating units derived from a dicarboxylic acid component, and repeating units derived from a diol component, the dicarboxylic acid component comprising cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof, is environmentally friendly because of the high content of recycled raw materials, and has excellent physical properties and biodegradability.

Description

Polyester copolymer containing recycled materials

[0001] The present invention relates to a polyester copolymer having a high content of recycled raw materials and excellent physical properties and biodegradability.

[0002] Polyvinyl chloride (PVC) is transparent, has excellent strength, and is used in various industrial fields because its desired physical properties can be easily controlled depending on the type of additives incorporated during processing. For example, by adding plasticizers to PVC with controlled amounts, it is possible to obtain soft PVC, which is used in the manufacture of flexible products such as packaging films and shower curtains, or rigid PVC, which is used in the manufacture of hard products such as plumbing materials.

[0003] However, due to controversy regarding the harmfulness of phthalate-based materials used as plasticizers to the environment and human health, the use of PVC has recently been restricted. Furthermore, since PVC generates dioxins, which are toxic substances, upon combustion, there is no disposal method other than landfilling. Therefore, there is a demand for the development of materials that can replace PVC.

[0004] Polyester is widely used as a material for beverage filling containers, packaging films, audio and video films, etc., because of its excellent mechanical strength, heat resistance, transparency, and gas barrier properties. It is also widely produced globally as an industrial material, such as medical fibers and tire cords. Polyester sheets and plates have good transparency and excellent mechanical strength, so they are widely used as materials for cases, boxes, partitions, store shelves, protective panels, blister packaging, building materials, and interior and exterior materials.

[0005] Meanwhile, waste plastics, which account for about 70% of marine pollution, have recently emerged as a serious social problem. Consequently, countries are regulating the use of single-use plastics while simultaneously promoting the reuse of waste plastics. Recycling methods for waste plastics can be broadly classified into two categories: one involves collecting, crushing, and washing waste plastics, then melt-extruding them to form pellets for re-pelletization, which are then used as raw materials; the other involves depolymerizing waste plastics to obtain materials which are then used as monomers for plastic synthesis. In the latter case, depolymerizing PET or PETG among waste plastics can yield bis-2-hydroxyethyl terephthalate, and research is underway to use this as a monomer for polyester copolymers.

[0006] While researching polyester synthesis using recycled raw materials, we confirmed that introducing a cyclohexyl structure polymerizes polyester with improved flexibility, thereby completing this study.

[0007] [Prior Art Literature]

[0008] [Patent Literature]

[0009] (Patent Document 1) Republic of Korea Registered Patent No. 10-2583652

[0010] To solve the above-mentioned problems, the present invention aims to provide a polyester copolymer having a high content of recycled raw materials while possessing softness and biodegradability.

[0011] To solve the above problems, the present invention provides a polyester copolymer comprising a repeating unit (A) derived from a recycled raw material; a repeating unit (B) derived from a dicarboxylic acid component; and a repeating unit (C) derived from a diol component, wherein the dicarboxylic acid component comprises cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof.

[0012] In addition, the present invention ensures that the content of the repeating unit (A) derived from the recycled raw material is 10 mol% to 90 mol% based on the total molar amount of the repeating unit (AB) derived from the recycled raw material and the dicarboxylic acid component.

[0013] The polyester copolymer according to the present invention has excellent physical properties and biodegradability while increasing the content of recycled materials through a combination of recycled materials and constituent components.

[0014] The present invention will be described in detail below with reference to the drawings.

[0015] The present invention will be described in detail below. Hereinafter, the present invention is not limited to the contents described below, but may be modified in various forms as long as the essence of the invention is not altered.

[0016] In this specification, when a part is described as "comprising" a certain component, this means that, unless specifically stated otherwise, it does not exclude other components but may include additional components.

[0017] All numbers and expressions indicating the amounts of components, reaction conditions, etc. described in this specification should be understood as being modified by the term "about" in all cases unless otherwise specified.

[0018] In this specification, terms such as "first," "second," etc. are used to describe various components, and said components are not limited by said terms. These terms are used solely for the purpose of distinguishing one component from another.

[0019] Where a numerical range with a limited upper limit and a numerical range with a limited lower limit are described in this specification to exemplify the size, physical properties, etc. of a component, it should be understood that a numerical range combining these upper and lower limits is also included within the exemplary scope of the present invention.

[0020] In this specification, singular expressions should be interpreted to include the singular or plural as interpreted in context unless otherwise specified.

[0021] The present invention is not limited to the contents disclosed below, but can be modified in various forms as long as the essence of the invention is not altered.

[0022]

[0023] Polyester copolymer

[0024] The polyester copolymer according to the present invention comprises a repeating unit (A) derived from a recycled raw material; a repeating unit (B) derived from a dicarboxylic acid component; and a repeating unit (C) derived from a diol component.

[0025] In this case, the dicarboxylic acid component comprises cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof.

[0026] The above polyester copolymer may have a glass transition temperature measured by differential scanning calorimetry (DSC) of 1 ℃ or higher, 2 ℃ or higher, 3 ℃ or higher, 4 ℃ or higher, 5 ℃ or higher, 10 ℃ or higher, 15 ℃ or higher, or 20 ℃ or higher, and may have a glass transition temperature of 90 ℃ or lower, 60 ℃ or lower, 55 ℃ or lower, 50 ℃ or lower, or 45 ℃ or lower. For example, the above polyester copolymer may have a glass transition temperature measured by differential scanning calorimetry (DSC) of 1 ℃ to 90 ℃, 1 ℃ to 60 ℃, or 5 ℃ to 45 ℃.

[0027] The above polyester copolymer may not have a melting temperature (Tm) measured by differential scanning calorimetry (DSC), or if the melting temperature (Tm) is measured by differential scanning calorimetry (DSC), the melting temperature (Tm) measured by differential scanning calorimetry (DSC) may be 240 ℃ or lower. Specifically, the melting temperature (Tm) of the polyester resin may be 240 ℃ or lower, 230 ℃ or lower, 220 ℃ or lower, 210 ℃ or lower, 200 ℃ or lower, 190 ℃ or lower, 185 ℃ or lower, 180 ℃ or lower, 179 ℃ or lower, 178 ℃ or lower, 177 ℃ or lower, or 176 ℃ or lower. Meanwhile, the above polyester copolymer may have a melting temperature (Tm) measured by differential scanning calorimetry (DSC) of 40 ℃ or higher, 45 ℃ or higher, 50 ℃ or higher, 60 ℃ or higher, 70 ℃ or higher, 80 ℃ or higher, 90 ℃ or higher, 100 ℃ or higher, 110 ℃ or higher, 120 ℃ or higher, 130 ℃ or higher, 140 ℃ or higher, 150 ℃ or higher, 160 ℃ or higher, 161 ℃ or higher, 162 ℃ or higher, 163 ℃ or higher, 164 ℃ or higher, or 165 ℃ or higher. For example, the melting temperature (Tm) of the polyester copolymer may not be measured by differential scanning calorimetry (DSC), or when the melting temperature (Tm) is measured by differential scanning calorimetry (DSC), the melting temperature (Tm) measured by differential scanning calorimetry (DSC) may be 40 ℃ to 240 ℃, 45 ℃ to 190 ℃, 50 ℃ to 180 ℃, 60 ℃ to 180 ℃, 70 ℃ to 185 ℃, 160 ℃ to 180 ℃, 163 ℃ to 178 ℃, or 165 ℃ to 176 ℃.

[0028] The polyester copolymer may have a hardness of 30 shore D or higher, 35 shore D or higher, 40 shore D or higher, 45 shore D or higher, or 50 shore D or higher, and may have a hardness of 90 shore D or lower, 85 shore D or lower, or 80 shore D or lower. For example, the polyester copolymer may have a hardness of 30 shore D to 90 shore D, 45 shore D to 85 shore D, or 50 shore D to 80 shore D.

[0029] The above polyester copolymer may have a biodegradability of 2% or more, 3% or more, 4% or more, or 5% or more after 90 days in accordance with UNI EN ISO 14855-1:2013, and may have a biodegradability of 40% or less, 35% or less, 30% or less, or 25% or less. For example, the above polyester copolymer may have a biodegradability of 2% to 40%, 2% to 35%, 3% to 30%, or 5% to 25% after 90 days in accordance with UNI EN ISO 14855-1:2013.

[0030]

[0031] Renewable materials

[0032] The polyester copolymer according to the present invention comprises repeating units (A) derived from recycled raw materials.

[0033] At this time, the content of repeating units (A) derived from the recycled raw material can be defined based on the total number of moles of repeating units (AB) derived from the recycled raw material and the dicarboxylic acid component.

[0034] The content of the repeating unit (A) derived from the above-mentioned recycled raw material may be 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total molar amount of the repeating unit (AB) derived from the above-mentioned recycled raw material and the dicarboxylic acid component, and may be 99.9 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the repeating unit (A) derived from the above-mentioned recycled raw material may be 10 mol% to 90 mol% based on the total number of moles of the repeating unit (AB) derived from the recycled raw material and the dicarboxylic acid component.

[0035] The above recycled raw material may be produced through a depolymerization reaction of waste polyester resin. Specifically, the above recycled raw material may include bis(2-hydroxyethyl)terephthalate (BHET) or BHET oligomer.

[0036] The above bis(2-hydroxyethyl)terephthalate (BHET) is an ester of two ethylene glycols and one terephthalic acid, and is a compound formed as an intermediate in the process of producing polyesters such as polyethylene terephthalate (PET) through a polymerization reaction between ethylene glycols and terephthalic acid or their esters.

[0037] Meanwhile, bis(2-hydroxyethyl)terephthalate regenerated through the depolymerization of waste polyester resin contains oligomeric materials such as dimers and trimers, as well as byproducts derived from diethylene glycol (DEG) generated at high depolymerization temperatures. For example, during the manufacturing process of bis(2-hydroxyethyl)terephthalate, compounds other than BHET, specifically BHET analogs and BHET oligomers (e.g., dimers, trimers), as well as other esters and acetates, are generated. The BHET oligomer may be a dimer of bis(2-hydroxyethyl)terephthalate (BHET), a trimer of bis(2-hydroxyethyl)terephthalate (BHET), or a combination thereof.

[0038] The content of the repeating unit derived from the above BHET may be 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total molar amount of the repeating unit (A) derived from the recycled raw material, and may be 99.9 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the above BHET may be 0.1 mol% to 100 mol% based on the total molar amount of the repeating unit (A) derived from the recycled raw material.

[0039] The content of the repeating unit derived from the above BHET oligomer may be 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total molar amount of the repeating unit (A) derived from the recycled raw material, and may be 99.9 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the above BHET oligomer may be 0.1 mol% to 100 mol% based on the total molar amount of the repeating unit (A) derived from the recycled raw material.

[0040] Meanwhile, the polyester copolymer according to the present invention has an economic advantage as it utilizes oligomers (20-40% generated during BHET production using dimers, trimers, etc.) generated during BHET production, resulting in a high recycling content and the benefit of using by-products. In addition, the polyester copolymer according to the present invention is environmentally friendly as it can reduce the amount of petroleum-based ethylene glycol input by using recycled raw materials and reduce the amount of greenhouse gases by recycling waste.

[0041]

[0042] Dicarboxylic acid component

[0043] The polyester copolymer according to the present invention comprises repeating units (B) derived from a dicarboxylic acid component.

[0044] At this time, the content of repeating units (B) derived from the dicarboxylic acid component can be defined based on the total number of moles of repeating units (AB) derived from the regenerated raw material and the dicarboxylic acid component.

[0045] The content of the repeating unit (B) derived from the above dicarboxylic acid component may be 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total molar amount of the regenerated raw material and the repeating unit (AB) derived from the dicarboxylic acid component, and may be 99.9 mol% or less, 99 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the repeating unit (B) derived from the dicarboxylic acid component may be 10 mol% to 90 mol% based on the total number of moles of the regenerated raw material and the repeating unit (AB) derived from the dicarboxylic acid component.

[0046] The above dicarboxylic acid component may include a first dicarboxylic acid component. Additionally, the above dicarboxylic acid component may include a first dicarboxylic acid component and a second dicarboxylic acid component.

[0047] The first dicarboxylic acid component comprises cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof. The first dicarboxylic acid component may comprise a dicarboxylic acid component derived from dimethylcyclohexanedicarboxylate (DMCD) or cyclohexanedicarboxylic acid (CHDA).

[0048] Meanwhile, the content of the repeating unit (B-1) derived from the first dicarboxylic acid component may be 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total moles of the repeating unit (B) derived from the dicarboxylic acid component, and may be 100 mol% or less, 99.9 mol% or less, 99 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the repeating unit (B-1) derived from the first dicarboxylic acid component may be 0.1 mol% to 100 mol% based on the total number of moles of the repeating unit (B) derived from the dicarboxylic acid component.

[0049] The above second dicarboxylic acid component is C6-C 20 Aromatic dicarboxylic acid, C6-C 20 Aliphatic dicarboxylic acid, C6-C 20 It may include one or more selected from the group consisting of cycloaliphatic dicarboxylic acids.

[0050] For example, the above C6-C 20 Examples of aromatic dicarboxylic acid components include isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, dimethyl isophthalate, diethyl isophthalate, dibutyl isophthalate, diphenyl dicarboxylic acid, 4,4'-stilbendicarboxylic acid, 2,5-furandicarboxylic acid, 2,5-thiophene dicarboxylic acid, etc., but are not limited thereto.

[0051] For example, the above C6-C 20Examples of aliphatic dicarboxylic acid components include succinic acid, adipic acid, sebacic acid, azeraic acid, dodecanoic acid, isodecylic succinic acid, maleic acid, fumaric acid, glutaric acid, etc., but are not limited thereto.

[0052] For example, the above C6-C 20 Examples of cycloaliphatic dicarboxylic acid components include tetrahydrophthalic anhydride, but are not limited to these.

[0053] The above second dicarboxylic acid component may include one or more selected from the group consisting of succinic acid, adipic acid, sebacic acid, azeraic acid, dodecanoic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, dimethyl isophthalate, diethyl isophthalate, and dibutyl isophthalate.

[0054] Meanwhile, the content of the repeating unit (B-2) derived from the second dicarboxylic acid component may be 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total moles of the repeating unit (B) derived from the dicarboxylic acid component, and may be 99.9 mol% or less, 99 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the repeating unit (B-2) derived from the second dicarboxylic acid component may be 0.1 mol% to 99.9 mol% based on the total number of moles of the repeating unit (B) derived from the dicarboxylic acid component.

[0055]

[0056] Dior ingredients

[0057] The polyester copolymer according to the present invention comprises a diol component.

[0058] The above diol component is C2-C 10 It may include diol, polyethylene glycol (PEG), polytrimethylene ether glycol (PO3G), polypropylene glycol (PPG), or polytetramethylene glycol (PTMG).

[0059] For example, the above C2-C 10 The diol may include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,6-hexanediol, 2,3-hexanediol, 2,4-hexanediol, 2,5-hexanediol, 2,6-hexanediol, 3,4-hexanediol, 1,2-cyclohexanedimethanol, 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, neopentylene glycol, etc. As a more specific example, the above C2-C 10 The diol may include one or more selected from the group consisting of ethylene glycol, 1,4-butanediol, neopentylene glycol, cyclohexanedimethanol, 1,2-propanediol, 1,3-propanediol, and 1,6-hexanediol.

[0060] The above diol component may include one or more selected from the group consisting of ethylene glycol (EG) and derivatives thereof or 1,4-butanediol (1,4-BD) and derivatives thereof. More specifically, the above diol component may include one or more selected from the group consisting of ethylene glycol (EG) or 1,4-butanediol (1,4-BD).

[0061] The content of repeating units (C) derived from the above diol component can be defined based on the total number of moles of repeating units (AB) derived from the recycled raw material and the dicarboxylic acid component.

[0062] Meanwhile, the content of the repeating unit (C) derived from the above diol component may be 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, or 65 mol% or more, based on the total molar amount of the repeating unit (AB) derived from the above regenerated raw material and the dicarboxylic acid component, and may be 400 mol% or less, 350 mol% or less, 300 mol% or less, 250 mol% or less, 200 mol% or less, 150 mol% or less, 105 mol% or less, 100 mol% or less, 95 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, or 75 mol% or less. For example, the content of the repeating unit (C) derived from the above diol component may be 50 mol% to 250 mol% based on the total number of moles of the repeating unit (AB) derived from the above regenerated raw material and the dicarboxylic acid component.

[0063] The content of the repeating unit derived from the above ethylene glycol (EG) may be 0 mol% or more, 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total molar amount of the repeating unit (C) derived from the diol component, and may be 100 mol% or less, 99.9 mol% or less, 99 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the repeating unit derived from the ethylene glycol (EG) may be 10 mol% to 100 mol% based on the total number of moles of the repeating unit (C) derived from the diol component.

[0064] The content of the repeating unit derived from the above 1,4-butanediol (1,4-BD) may be 0 mol% or more, 0.1 mol% or more, 1 mol% or more, 5 mol% or more, 10 mol% or more, 20 mol% or more, 30 mol% or more, 40 mol% or more, 50 mol% or more, 60 mol% or more, 70 mol% or more, 80 mol% or more, or 85 mol% or more, based on the total number of moles of the repeating unit (C) derived from the diol component, and may be 100 mol% or less, 99.9 mol% or less, 99 mol% or less, 90 mol% or less, 85 mol% or less, 80 mol% or less, 70 mol% or less, 60 mol% or less, 50 mol% or less, 40 mol% or less, 30 mol% or less, 20 mol% or less, or 15 mol% or less. For example, the content of the repeating unit derived from the above 1,4-butanediol (1,4-BD) may be 10 mol% to 100 mol% based on the total number of moles of the repeating unit (C) derived from the diol component.

[0065]

[0066] Method for manufacturing a polyester copolymer

[0067] A method for manufacturing a polyester copolymer according to another embodiment of the present invention comprises the steps of: mixing a recycled raw material, a dicarboxylic acid component, and a diol component; esterifying the mixture; and polycondensing the product of the esterification reaction, wherein the polyester copolymer contains a repeating unit (A) derived from the recycled raw material in an amount of 10 mol% to 90 mol% based on the total molar amount of repeating units (AB) derived from the recycled raw material and the dicarboxylic acid component.

[0068] The polyester copolymer produced according to the above method for producing the polyester copolymer has substantially the same composition and characteristics as the polyester copolymer described above.

[0069] In addition, the final polyester copolymer produced according to the above method for manufacturing the polyester copolymer can have its composition and process conditions adjusted to satisfy mechanical properties such as softness and elasticity, optical properties such as transparency and UV stability, and processability, as described above.

[0070]

[0071] First, the recycled raw material, dicarboxylic acid component, and diol component are mixed.

[0072] The descriptions of the above-mentioned regenerated raw material, the above-mentioned dicarboxylic acid component, and the above-mentioned diol component are as previously stated. Specifically, the above-mentioned regenerated raw material, the above-mentioned dicarboxylic acid component, and the above-mentioned diol component are mixed to produce a mixture.

[0073] According to another embodiment of the present invention, one or more additives selected from the group consisting of a colorant, a crystallizing agent, an oxidation stabilizer, and a branching agent may be additionally added to the mixture of the regenerated raw material, the dicarboxylic acid component, and the diol component.

[0074] The above-mentioned colorant is an additive for improving the color characteristics of the polyester copolymer. As long as it does not impede the effects of the present invention, commonly used colorants such as cobalt acetate, cobalt propionate, etc. may be used as the colorant.

[0075] Specifically, the above-mentioned colorant may be cobalt acetate, cobalt propionate, anthraquinone-based compounds, perinone-based compounds, azo-based compounds, methine-based compounds, etc., and commercially available products may include toners such as Clarient’s Polysynthren Blue RLS or Clarient’s Solvaperm Red BB.

[0076] In addition, the polyester copolymer may contain the colorant in an amount of 0.1 ppm to 30 ppm based on the total weight of the polyester copolymer. For example, the colorant 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 above ranges for the content of the colorant, color characteristics can be sufficiently improved without degrading the mechanical properties of the polyester copolymer.

[0077] The above crystallizing agent may include one or more selected from the group consisting of a crystallization nucleating agent, a UV absorber, a polyolefin resin, a polyamide resin, a polyester resin, a polyester elastomer resin, and a polyalkylene resin.

[0078] In addition, the polyester copolymer may contain the crystallizing agent in an amount of 0.1 ppm to 20 weight% based on the total weight of the polyester copolymer. For example, the crystallizing agent may be added in an amount of 0.2 ppm to 20 weight%, 0.5 ppm to 15 weight%, 1 ppm to 10 weight%, 2 ppm to 8 weight%, 3 ppm to 5 weight%, or 4 ppm to 1 weight% based on the total weight of the mixture. By satisfying the above ranges for the content of the crystallizing agent, mechanical properties such as heat resistance and impact strength can be improved.

[0079] The above oxidation stabilizer may include one or more selected from the group consisting of phosphorus-based, hindered phenol-based, phosphite-based, and thioether-based agents.

[0080] In addition, the polyester copolymer may contain the oxidation stabilizer in an amount of 50 ppm to 2,500 ppm based on the total weight of the polyester copolymer. 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 above ranges for the content of the oxidation stabilizer, not only can the decrease in intrinsic viscosity that may occur during subsequent processing be effectively prevented, but the deterioration of physical properties such as impact strength can also be prevented.

[0081] The above branching agent may include one or more selected from the group consisting of trimellitic anhydride, trimethylol propane, trimellitic acid, and glycerol.

[0082] In addition, the polyester copolymer may contain the branching agent in an amount of 10 ppm to 5000 ppm based on the total weight of the polyester copolymer. 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 above range, the intrinsic viscosity can be controlled more effectively within a specific range, thereby improving physical properties such as impact strength.

[0083]

[0084] Afterwards, the above mixture is subjected to an esterification reaction.

[0085] Specifically, a mixture of the above-mentioned recycled raw material, dicarboxylic acid component, and diol component is subjected to an esterification reaction.

[0086] The above esterification reaction is carried out at atmospheric pressure or 0.1 kg / cm² relative to atmospheric pressure. 2 up to 3.0 kg / cm² 2 It can be performed for 2 to 12 hours under high pressure conditions and a temperature condition of 245 ℃ to 275 ℃.

[0087] Specifically, the above pressurized state is 0.1 kg / cm² relative to atmospheric pressure. 2 up to 3.0 kg / cm² 2 , 0.2 kg / cm 2 up to 2.5 kg / cm² 2 or 0.3 kg / cm² 2 Up to 2.0 kg / cm² 2 It can be as high as that. In addition, the esterification reaction can be carried out for 2 to 12 hours, 2 to 11 hours, or 2.5 to 10 hours under temperature conditions of 150 ℃ to 275 ℃, 155 ℃ to 275 ℃, or 160 ℃ to 270 ℃.

[0088] For example, the above esterification reaction is at atmospheric pressure or 0.1 kg / cm² relative to atmospheric pressure. 2 up to 3.0 kg / cm² 2 This can be performed by increasing the temperature from room temperature to 150°C to 275°C or 155°C to 270°C over 30 minutes to 110 minutes or 30 minutes to 100 minutes under high pressure, maintaining it for 0.5 hours to 3 hours or 0.5 hours to 2.5 hours, and then increasing the temperature continuously or in steps from room temperature to 150°C to 275°C or 155°C to 270°C over 2 hours to 12 hours.

[0089] Once the above esterification reaction is completed, the pressure of the pressurized reactor can be lowered to room temperature, and then the following polycondensation reaction can be performed.

[0090]

[0091] Finally, the product of the above esterification reaction is subjected to a polycondensation reaction.

[0092] The above polycondensation reaction may be carried out for 1 hour to 12 hours under pressure conditions of 0.00001 mmHg to 400 mmHg and temperature conditions of 240 ℃ to 300 ℃. For example, the above polycondensation reaction may be carried out for 1 hour to 12 hours or 1 hour to 10 hours under pressure conditions 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 temperature conditions of 240 ℃ to 300 ℃ or 245 ℃ to 295 ℃.

[0093] For example, the polycondensation reaction may be carried out by reducing the pressure of the product of the esterification 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, increasing the temperature to 240 ℃ to 300 ℃ or 245 ℃ to 295 ℃ over 0.5 to 2 hours or 0.7 to 1.2 hours, and then maintaining a pressure of 0.01 mmHg to 400 mmHg.

[0094] In the initial stages of the polycondensation reaction, the stirring speed is set to a high speed, and as the polycondensation reaction proceeds, the stirring force may weaken due to an increase in the viscosity of the reactants or the temperature of the reactants may rise above the set temperature, at which point the stirring speed can be appropriately adjusted accordingly.

[0095] The intrinsic viscosity (IV) of the melt produced by the above polycondensation reaction may be 0.5 dl / g to 1.3 dl / g. For example, the polycondensation reaction may be carried out until the intrinsic viscosity (IV) of the melt produced by the above polycondensation reaction becomes 0.5 dl / g to 1.2 dl / g, or 0.6 dl / g to 1.15 dl / g.

[0096] In addition, a catalyst and / or stabilizer may be additionally added in the above esterification reaction and the above polycondensation reaction.

[0097] For example, the esterification reaction catalyst may be a methylate of sodium or magnesium; an acetate, borate, fatty acid, or carbonate of Zn, Cd, Mn, Co, Ca, Ba, etc.; a metal Mg; or an oxide of Pb, Zn, Sb, Ge, etc.

[0098] In addition, the polycondensation reaction catalyst may be a titanium-based catalyst such as, for example, tetraethyl titanate, acetyltripropyl titanate, tetrapropyl titanate, tetrabutyl titanate, polybutyl titanate, 2-ethylhexyl titanate, octylene glycol titanate, lactate titanate, triethanolamine titanate, acetylacetonate titanate, ethylacetoacetic 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, monobutylhydroxy tin oxide, etc.

[0099] In addition, the above stabilizer may be a phosphorus-based compound such as phosphoric acid, trimethyl phosphate, or triethyl phosphate, but is not limited thereto.

[0100] The above stabilizer may be added in an amount of 10 ppm to 2,500 ppm based on the total weight of the polycondensation reactants. For example, the above 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 reactants.

[0101]

[0102] The above contents will be explained in more detail by the following examples. However, the following examples are merely for illustrating the present invention, and the scope of the examples is not limited to these.

[0103]

[0104] [Example]

[0105] Preparation of polyester copolymer

[0106] Example 1

[0107] (1) Esterification reaction

[0108] 781 g (3.08 mol) of BHET (bis(2-hydroxyethyl) terephthalate), 2,462 g (12.30 mol) of dimethylcyclohexane dicarboxylate (DMCD), and 954 g (15.37 mol) of ethylene glycol (EG) were added to a 10 L reactor connected to a column and a condenser that can be cooled by water.

[0109] Subsequently, 0.853 g of tetrabutyl titanate (TBT) as a catalyst, 0.235 g of phosphoric acid as a stabilizer, and 1.47 g of trimellitic anhydride as a branching agent were added and stirred.

[0110] Subsequently, nitrogen is injected into the reactor so that the pressure in the reactor is 1.0 kgf / cm² relative to atmospheric pressure. 2The reactor was subjected to a high pressurization state (absolute pressure: 1495.6 mmHg). Then, the temperature of the reactor was raised from room temperature to 200 ℃ over 60 minutes, maintained at 200 ℃ for 2 hours, and then raised again to 245 ℃ over 5 hours. Subsequently, the esterification reaction was carried out at a temperature of 245 ℃ for 0.5 hours. During this process, byproducts were discharged through a column and a condenser. Once the esterification reaction was completed, the nitrogen inside the pressurized reactor was purged to lower the reactor pressure to atmospheric pressure, and the product of the esterification reaction inside the reactor was transferred to a 7L volume reactor capable of vacuum reaction.

[0111] (2) Polycondensation reaction

[0112] The pressure of the reactor into which the product obtained through the above esterification reaction was introduced 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 ℃ over 1 hour, and then the pressure of the reactor was maintained at 1.0 Torr (absolute pressure: 1.0 mmHg) or lower to carry out the polycondensation reaction. At this time, the stirring speed was set fast at the beginning of the polycondensation reaction, but as the polycondensation reaction proceeded, if the stirring force weakened due to the increase in viscosity of the reactants or if the temperature of the reactants rose above the set temperature, the stirring speed was appropriately adjusted accordingly. The above polycondensation reaction was carried out until the intrinsic viscosity (IV) of the mixture (molten material) in the reactor was 1.0 dl / g or higher, after which the mixture was discharged out of the reactor and formed into strands, and then solidified with a cooling liquid and granulated to have an average weight of about 12 mg to 14 mg to produce a polyester copolymer.

[0113]

[0114] Examples 2 to 6

[0115] A polyester copolymer was prepared in the same manner as in Example 1, except that the raw material components and their content were adjusted as shown in the table below.

[0116]

[0117] Comparative Examples 1 to 2

[0118] The amount of raw materials was adjusted as shown in the table below, and a sample was prepared by polymerizing in the same manner as in the example.

[0119] Classification Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Content of repeating units (AB) relative to total moles of repeating units (AB) derived from recycled raw materials and dicarboxylic acid components (Moll%) BHET204060--80--BHET oligomer---7060--- Content of repeating units relative to total moles of (AB) (Moll%) TPA------4060DMCD8060403040206040 Content of repeating units relative to total moles of (AB) (Moll%) EG1008050200020001,4-BD003050100880150PTMG00000200NPG002000000CHDM00000000

[0120] Preparation Example: Preparation of a specimen for hardness measurement

[0121] For the polyester copolymers prepared in Examples 1 to 6 and Comparative Examples 1 and 2 above, flat specimens with a thickness of 1 mm were prepared in a press equipped with a heating device. For Examples 1 to 6 and Comparative Example 2, specimens were prepared at 220 ℃, and for Comparative Example 1, specimens were prepared at 250 ℃.

[0122]

[0123] Experimental Example 1. Measurement of Physical Properties

[0124] Measurement of physical properties using Differential Scanning Calorimetry (DSC)

[0125] For the specimens prepared according to Examples 1 to 6 and Comparative Examples 1 and 2 above, the glass transition temperature (Tg) was measured using a differential scanning calorimeter (DSC). In addition, for the specimens prepared according to Example 5, Example 6 and Comparative Example 2, the melting temperature (Tc) was measured using a differential scanning calorimeter (DSC).

[0126] Specifically, for the copolymer, a first scan was obtained using a differential scanning calorimeter by increasing the temperature from -40 ℃ to 280 ℃ by 10 ℃ and maintaining it at 280 ℃ for 2 minutes, then decreasing the temperature from 280 ℃ to -20 ℃ to -300 ℃ and maintaining it for 15 minutes, and then increasing the temperature again from -40 ℃ to 280 ℃ by 10 ℃ to obtain a second scan. The glass transition temperature (Tg) and melting temperature (Tm) were measured from the heat flow curves obtained during the above process.

[0127]

[0128] Shore hardness measurement

[0129] Shore D hardness was measured for the polyester copolymers of Examples 1 to 6 and Comparative Examples 1 and 2 according to ASTM D2240-05.

[0130] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Glass Transition Temperature (°C) 25 40 31 35 9 20 40 9 Melting Temperature (°C) ---- 165 176 - 160 Hardness (Shore D) 50 80 77 78 75 68 79 75

[0131] As shown in the table above, it was confirmed that Examples 1 to 6 have a glass transition temperature of 9°C to 40°C, and Comparative Examples 1 to 2 have a glass transition temperature of 9°C to 40°C. In addition, it was confirmed that Examples 5 and 6 have a melting temperature of 165°C to 176°C, and Comparative Example 2 has a melting temperature of 160°C.

[0132] Meanwhile, it was confirmed that Examples 1 to 6 have a hardness of 50 shore D to 80 shore D, and Comparative Examples 1 to 2 have a hardness of 75 shore D to 79 shore D.

[0133]

[0134] Experimental Example 2. Measurement of Biodegradability

[0135] The biodegradability of specimens prepared using the polymer resin compositions of Examples 1 to 6 and Comparative Examples 1 and 2 was measured over a period of 90 days in accordance with UNI EN ISO 14855-1:2013. UNI EN ISO 14855-1:2013 is a method for measuring the aerobic biodegradability and disintegration of plastics, which are organic compounds, by measuring the amount of carbon dioxide generated under composting conditions. This test is basically conducted for 90 days, in which the test material is cultured with a compost inoculum, and the percentage of biodegradability is obtained by measuring the rate at which the organic carbon of the test material is converted into inorganic carbon in the form of CO2 in the gaseous phase. Specifically, a polyester copolymer sample was freeze-ground to form particles of 20 μm or less, and then the particles were mixed into a culture medium composed of urea, starch, inorganic materials, etc., according to a standard method. The amount of carbon dioxide released over 90 days was measured while maintaining a constant temperature of 58 ℃, and the biodegradability was calculated based on the change in weight.

[0136] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Comparative Example 1 Comparative Example 2 Biodegradability (%) 1487 152 224822

[0137] As shown in the table above, Example 2 has a composition similar to Comparative Example 1 except that BHET was used instead of TPA, and showed a biodegradability value comparable to Comparative Example 1 using TPA. Meanwhile, Example 5 has a composition similar to Comparative Example 2 except that BHET oligomer was used instead of TPA, and showed a biodegradability value comparable to Comparative Example 2 using TPA.

Claims

1. Repeating unit (A) derived from recycled materials; Repeating unit (B) derived from a dicarboxylic acid component; and It includes repeating units (C) derived from a diol component, and The above dicarboxylic acid component is a polyester copolymer comprising cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof.

2. In Paragraph 1, A polyester copolymer in which the content of the repeating unit (A) derived from the above-mentioned recycled raw material is 10 mol% to 90 mol% based on the total molar amount of the repeating unit (AB) derived from the above-mentioned recycled raw material and the dicarboxylic acid component.

3. In Paragraph 1, The above recycled material is a polyester copolymer produced through the depolymerization reaction of waste polyester resin.

4. In Paragraph 1, The above recycled material is a polyester copolymer comprising bis(2-hydroxyethyl)terephthalate (BHET) or BHET oligomer.

5. In Paragraph 4, The above BHET oligomer is a polyester copolymer comprising a dimer of bis(2-hydroxyethyl)terephthalate (BHET), a trimer of bis(2-hydroxyethyl)terephthalate (BHET), or a combination thereof.

6. In Paragraph 1, A polyester copolymer in which the content of the repeating unit (B) derived from the above dicarboxylic acid component is 10 mol% to 90 mol% based on the total molar amount of the regenerated raw material and the repeating unit (AB) derived from the dicarboxylic acid component.

7. In Paragraph 1, The above-mentioned dicarboxylic acid component comprises a derivative derived from dimethylcyclohexanedicarboxylate (DMCD) or cyclohexanedicarboxylic acid (CHDA), a polyester copolymer.

8. In Paragraph 1, The above dicarboxylic acid component includes a first dicarboxylic acid component and a second dicarboxylic acid component, and The first dicarboxylic acid component comprises cyclohexanedicarboxylic acid (CHDA), dimethylcyclohexanedicarboxylate (DMCD), or a combination thereof, and The above second dicarboxylic acid component is C6-C 20 Aromatic dicarboxylic acid, C6-C 20 aliphatic dicarboxylic acids and C6-C 20 A polyester copolymer comprising one or more selected from the group consisting of cycloaliphatic dicarboxylic acids.

9. In Paragraph 1, The above diol component is C2-C 10 A polyester copolymer comprising one or more selected from the group consisting of a diol, polyethylene glycol (PEG), polytrimethylene ether glycol (PO3G), polypropylene glycol (PPG), and polytetramethylene glycol (PTMG).

10. In Paragraph 1, The above diol component is a polyester copolymer comprising ethylene glycol (EG), 1,4-butanediol (1,4-BD), or a combination thereof.

11. In Paragraph 1, The above polyester copolymer is a polyester copolymer having a glass transition temperature of 1°C to 60°C as measured by differential scanning calorimetry (DSC).

12. In Paragraph 1, The above polyester copolymer is a polyester copolymer having a hardness of 30 shore D to 90 shore D.

13. In Paragraph 1, The above polyester copolymer is a polyester copolymer having a biodegradability of 2% or more as measured by UNI EN ISO 14855-1:2013.

14. In Paragraph 1, The above polyester copolymer is a polyester copolymer having a biodegradability of 2% to 40% as measured by UNI EN ISO 14855-1:2013.