Renewable molded articles from blends of copolyesters and regenerated PET

Abstract

The present disclosure relates to a renewable molded article made from a blend of a renewable PET and a copolyester composition comprising residues of terephthalic acid, neopentyl glycol (NPG), 1, 4-cyclohexanedimethanol (CHDM), ethylene glycol (EG), and / or 2, 2, 4, 4-tetramethyl-1, 3-cyclobutanediol in specific compositional ranges, the renewable extrusion blow molded article being thick walled (> 4 mm), and having a cross-linked structure, the PET film has a high level of regenerated PET content, has low haze and can be regenerated in the PET process.

Description

[0001] This application is a divisional application, and the filing date of its parent application is May 8, 2020, the application number is 202080034850.7, and the invention title is "Renewable Moldings from Blends of Copolyester and Recycled PET". Technical Field

[0002] The present disclosure relates to renewable moldings made from blends of recycled PET and copolyester compositions having certain advantages and improved properties, the copolyester compositions comprising residues of terephthalic acid, neopentyl glycol (NPG), 1,4-cyclohexanedimethanol (CHDM), ethylene glycol (EG), and / or 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues within specific compositional ranges. Background Art

[0003] There is a commercial need for transparent, clear, strong, and chemically resistant renewable moldings made from copolyester thermoplastics.

[0004] A product must be convertible back into a usable polymeric material at the end of its life to be considered renewable. Currently, poly(ethylene terephthalate) (PET) is the most abundant thermoplastic with a well-established mechanical recycling process.

[0005] The recycling of post-consumer PET is a complex process involving the separation of opaque, colored, and transparent components from each other and from containers made of different materials (such as polyethylene, polypropylene, PVC, etc.). Proper separation is crucial because these materials can each contaminate the PET process and degrade the quality of the final sorted product. After separation, the transparent PET bottles are ground into flakes, cleaned, and dried at a temperature of 140°C to 180°C. The flakes can be used directly (e.g., for strapping and fiber extrusion) or further processed into pellets for film, sheet, or bottle applications. For some applications, the pellets can be further crystallized and solid-state polymerized at a temperature of 200°C to 220°C before use. Due to the well-established nature of this process, it is desirable for copolyester-based moldings and containers to be compatible with existing PET recycling streams.

[0006] There is also a desire to incorporate recycled PET (rPET) back into new molded or extruded articles. The use of rPET reduces the environmental footprint of the products provided and improves the overall life cycle analysis. Finally, it may be desirable for rPET to be used in more durable consumer-oriented product applications with longer useful lives. For example, one such industry is the cosmetics and personal care industry, where the packaging itself is often an important part of the product's appeal. Other industries include, but are not limited to, durable consumer goods, appliances and components, furniture components, electronic devices or peripherals, and durable packaging. In these industries, the use of rPET provides economic advantages and will reduce the total amount of packaging-related products sent to landfills or that may ultimately pollute the oceans or other bodies of water. Thus, incorporating more rPET into more durable product markets and applications where currently used resins lack similar renewable or recycled content options provides a compelling solution. However, historically, rPET has had limitations that have hindered its use in many of these types of applications.

[0007] This disclosure addresses this long-felt commercial need for durable molded articles made from copolyester thermoplastic materials that are transparent, clear, strong, and chemical-resistant, contain significant levels of rPET, and are also recyclable in PET processes. SUMMARY OF THE INVENTION

[0008] One embodiment of the disclosure is a renewable thick-walled article comprising an rPET / copolyester blend, the blend comprising: (1) 15-50 wt% recycled polyethylene terephthalate (rPET) and (2) 50-85 wt% of at least one copolyester, comprising: (a) a dicarboxylic acid component, comprising: i) 70 to 100 mol% terephthalic acid residues; ii) 0 to 30 mol% aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a glycol component, comprising: i) 0 to 35 mol% 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues; ii) 0 to 50 mol% 1,4-cyclohexanedimethanol residues, iii) 0 to 50 mol% neopentyl glycol residues; iv) 0 to 35 mol% other modified glycol residues; v) up to 98 mol% ethylene glycol residues; where the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the glycol component is 100 mol%; and wherein the blend has a total comonomer content of 5-15 wt% of diols and acids other than ethylene glycol (EG), terephthalic acid (TPA) or dimethyl terephthalate (DMT); wherein the intrinsic viscosity of the copolyester, as measured at 25 °C at a concentration of 0.5 g / 100 ml in 60 / 40 (wt / wt) phenol / tetrachloroethane, is 0.50 to 0.9 dL / g; wherein the copolyester has a Tg of 70 to 115 °C; wherein the article has a melting temperature (Tm) of 225-255 °C or 235-250 °C; wherein the article has a haze value of 20% or less; and wherein the article has a thickness of 4-25 mm; wherein the article has a semi-crystallization time of about 3 minutes to about 20 minutes or about 3 to about 12 minutes or about 5 to about 15 minutes at 180 °C; wherein the article is recyclable in a PET recycling process.

[0009] One embodiment of the present disclosure is a renewable thick-walled article comprising an rPET / copolyester blend, the blend comprising: (1) 15-50 wt% of recycled polyethylene terephthalate (rPET) and (2) 50-85 wt% of a copolyester, which comprises: (a) a dicarboxylic acid component, which comprises: i) 70 to 100 mol% of terephthalic acid residues; ii) 0 to 30 mol% of aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a diol component, which comprises: i) 0 to 35 mol% of 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues; ii) 0 to 50 mol% of 1,4-cyclohexanedimethanol residues, iii) 0 to 50 mol% of neopentyl glycol residues; iv) 0 to 35 mol% of other modified diol residues; v) up to 98 mol% of ethylene glycol residues; wherein the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the diol component is 100 mol%; and wherein the blend has a total comonomer content of 5-15 wt% of diols and acids other than ethylene glycol (EG), terephthalic acid (TPA) or dimethyl terephthalate (DMT); wherein the intrinsic viscosity of the copolyester as measured at 25 °C at a concentration of 0.5 g / 100 ml in 60 / 40 (wt / wt) phenol / tetrachloroethane is from 0.50 to 0.9 dL / g; wherein the copolyester has a Tg of from 70 to 115 °C; wherein the article has a melt temperature (Tm) of 225 - 255 °C or 235 - 250 °C; wherein the article has a haze value of 20% or less; and wherein the article has a thickness of 4 - 25 mm; wherein the article has a semi-crystallization time of about 3 minutes to about 20 minutes or about 3 to about 12 minutes or about 5 to about 15 minutes at 180 °C; wherein the article is recyclable in a PET recycling process.

[0010] In one embodiment, the recyclable thick-walled article has a melting enthalpy (Hm) greater than 0.20 cal / g.

[0011] In one embodiment, the polyester has an intrinsic viscosity of 0.58 to 0.70 dL / g as measured at 25 °C at a concentration of 0.5 g / 100 ml in 60 / 40 (wt / wt) phenol / tetrachloroethane.

[0012] One aspect of the present disclosure is a method of making a recyclable thick-walled molded article, comprising: (A) compounding an rPET / copolyester blend, the blend comprising: (1) 15 - 50 wt% of recycled polyethylene terephthalate (rPET); and (2) 50 - 85 wt% of at least one copolyester, comprising: (a) a dicarboxylic acid component comprising: i) 70 to 100 mol% of terephthalic acid residues, dimethyl terephthalate and / or isophthalic acid; and ii) 0 to 30 mol% of aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a glycol component comprising: i) 0 to 35 mol% of 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues; ii) 0 to 50 mol% of 1,4-cyclohexanedimethanol residues; iii) 0 to 50 mol% of neopentyl glycol residues; iv) 0 to 35 mol% of other modified glycol residues; and v) up to 98 mol% of ethylene glycol residues; wherein the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the glycol component is 100 mol%; and wherein the blend has a total comonomer content of 5-15 wt% of diols and acids other than ethylene glycol (EG), terephthalic acid (TPA) or dimethyl terephthalate (DMT); (B) pelletizing the compounded blend; (C) drying the compounded blend at a temperature of 60-160 °C; (D) melting and injecting the compounded blend into a mold; and (E) ejecting the resulting molded article from the mold.

[0013] In one aspect, the articles of the present disclosure can be recycled in a PET recycling process.

[0014] In one embodiment, the blend composition of the present disclosure can be used as a manufactured article selected from at least one of: molded articles, bottles, films, sheets, containers, medical containers, personal care containers or cosmetic containers.

[0015] In one embodiment, the articles of the present disclosure can be used as films, containers, packaging articles, electrical components, cosmetic jars, bottles, medical containers, personal care containers, cosmetic containers, molded articles, caps, perfume bottle caps, tools, tool handles, toothbrushes, toothbrush handles, housings for electronic and / or acoustic devices, medical devices, medical packaging, health care products, commercial food service products, trays, containers, food trays, drums, storage bins, bottles, food processors, blender and mixer bowls, utensils, water bottles, crisper trays, washing machine components, refrigerator components, vacuum cleaner components, ophthalmic lenses and frames or toys. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 : Figure 1 Showing melt temperature data from the first heating DSC scan vs weight percentage (wt%) comonomer content (from monomers other than EG, TPA and DMT) in the molded article. DETAILED DESCRIPTION

[0017] The present disclosure may be more readily understood with reference to the following detailed description of certain embodiments and working examples of the present disclosure. Certain embodiments of the present disclosure are described in the Summary of the Invention and further described herein below in accordance with one or more objects of the present disclosure. Other embodiments of the present disclosure are also described herein.

[0018] The present disclosure relates to specific rPET / copolyesters blends that can be made into molded articles having the following properties, all of which are becoming increasingly important to market demands: (1) the composition contains a high level of post-consumer recycled (PCR) material in the form of rPET; (2) the articles are thick-walled (about 4-25 mm) and transparent (low haze); and (3) the composition has a melt temperature (Tm) of 225-255 °C, so they are eligible as PET for recycled use and can be recycled at the end of life with existing well-established PET recycling processes.

[0019] In one aspect, the molded articles of the present disclosure relate to environmentally friendly and sustainable articles based on copolyesters for durable and consumer-oriented product applications having two key properties. First, the articles of the present disclosure enable the ability to mold strong and transparent articles at thicknesses (about >4 mm) that are not currently achievable with homopolymer PET or rPET. Second, the articles of the present disclosure are compatible in PET recycling processes, i.e., they can be processed under conditions used for homopolymer PET recycling.

[0020] Regarding the first aspect, it is the crystallization rate of homopolymer PET (virgin or recycled) that significantly limits its utility for producing clear thick-walled articles. rPET typically crystallizes during processing and produces opaque white articles. Generally, it is difficult to produce clear articles and components from rPET at wall thicknesses of about 4 mm or greater.

[0021] Generally, the crystallization rate can be reduced by incorporating additional monomers into the PET polyester to produce modified copolyesters. An alternative to rPET or PET for such applications is a slower crystallizing PET copolyester. For example, copolymers are available in which the diol component in the copolymer is a mixture of ethylene glycol and a second diol such as 1,4-cyclohexanedimethanol (CHDM).

[0022] Generally, clear thick-walled cans and other molded articles can be produced from these copolymers. Although clear components are produced, the slow crystallization rate and lack of a discernible melting point at 225-250 °C of these copolyesters prevent these articles from being recycled in PET recycling processes. Generally, copolyesters can meet the first of the two properties discussed above, but typically fail the second.

[0023] For example, ground fragments from copolyesters can stick to the walls of the dryer or agglomerate with PET container fragments in a dryer set at 140-180 °C. Mixing ground fragments from copolyester articles into rPET fragments can also result in cloudy films, sheets, or bottles. These problems can occur at copolyester levels as low as 0.1%. But the present disclosure provides an ideal composition that is clear, can be injection molded into thick (>4 mm) transparent articles, and is not a problem in PET recycling processes.

[0024] In 2017, California Assembly Bill No. 906 - Beverage containers: polyethylene terephthalate was signed into law, and for the purpose of resin code classification, it defined "polyethylene terephthalate" (PET) as a plastic meeting certain conditions, including restrictions on the chemical composition of the polymer and a melting peak temperature within a specified range. AB - 906 added Section 18013 to California’s Public Resources Code, which reads in part: "Polyethylene terephthalate (PET)" means a plastic derived from the reaction between terephthalic acid or dimethyl terephthalate and monoethylene glycol, which meets the following two conditions: a. The terephthalic acid or dimethyl terephthalate and monoethylene glycol that react constitute at least 90% of the monomer mass that reacts to form the polymer.

[0025] b. The plastic exhibits a melting peak temperature between 225°C and 255°C, as determined during a second heat scan at a sample heating rate of 10°C / min using Procedure 10.1 described in ASTM International (ASTM) D3418.

[0026] Thus, copolyesters and the above blends that meet these two conditions outlined in AB - 906 can be accepted as "PET", and thus such materials are also compatible in existing PET recycling processes. The melting points of the blend compositions in the present disclosure render them acceptable under this definition of PET and thus compatible in existing PET recycling processes.

[0027] Accordingly, in one aspect of the present disclosure, "compatible with a PET recycling process" is defined as exhibiting a melting temperature of 225 - 255°C during the first heating DSC scan of a molded part (at a scan rate of 10 - 20°C / min), while also containing 15 wt% or less of diols and / or acids other than EG, TPA, or DMT (referred to herein as the total weight% of the comonomer content).

[0028] In the present disclosure, it has been found that blends of certain combinations of recycled PET and copolyesters can be made into thick - walled molded articles having (1) a high level of recycled PET content; (2) low haze (transparent); and (3) compatibility in a PET recycling process.

[0029] These molded articles in the present disclosure are also recyclable, and they can be processed with a PET recycling process and ultimately become components in the recyclable PET flakes leaving the recycling process. The optimized rPET / copolyester blend compositions of the present disclosure have a unique crystallization distribution based on the melting point of the copolyester to enable the molded articles to be recycled. Thus, they exhibit good properties as molded articles, but they have a high melting point, so they provide excellent performance in the recycling process. The molded articles of the present disclosure have a melting temperature and a weight % comonomer content loading consistent with the definition in the Assembly Bill, so it is expected that the molded articles of the present disclosure can be processed in a standard PET recycling process and they do not have to be removed during the recycling process because they will not affect the process.

[0030] In one aspect of the present disclosure, the presence of a melting temperature peak is crucial for functional selection as an acceptable recycled PET material. The articles of the present disclosure surprisingly exhibit a melting temperature of 225 - 255 °C, despite having a total comonomer content in the range of 5 - 15 weight %.

[0031] One embodiment of the present disclosure is a recyclable thick-walled article comprising an rPET / copolyester blend, the blend comprising: (1) 15 - 50 weight % of recycled polyethylene terephthalate (rPET) and (2) 50 - 85 weight % of at least one copolyester, which comprises: (a) a dicarboxylic acid component, which comprises: i) 70 to 100 mol % of terephthalic acid residues; ii) 0 to 30 mol % of aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a diol component, which comprises: i) 0 to 35 mol % of 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues; ii) 0 to 50 mol % of 1,4-cyclohexanedimethanol residues, iii) 0 to 15 mol % of neopentyl glycol residues; iv) 0 to 35 mol % of other modified diol residues; v) up to 98 mol % of ethylene glycol residues; wherein the total mol % of the dicarboxylic acid component is 100 mol %, and the total mol % of the diol component is 100 mol %; and wherein the blend has a total comonomer content of 5 - 15 weight % from diols and acids other than ethylene glycol (EG), terephthalic acid (TPA) or dimethyl terephthalate (DMT); wherein the intrinsic viscosity of the copolyester, as measured at 25 °C at a concentration of 0.5 g / 100 ml in 60 / 40 (wt / wt) phenol / tetrachloroethane, is from 0.50 to 0.9 dL / g; wherein the copolyester has a Tg of from 70 to 115 °C; wherein the article has a melting temperature (Tm) of 225 - 255 °C; wherein the article has a haze value of 20% or less; and wherein the article has a thickness of 4 - 25 mm; wherein the article has a semi-crystallization time of from about 3 minutes to about 20 minutes at 180 °C; wherein the article is recyclable in a PET recycling process.

[0032] In one embodiment, the article has a melting temperature (Tm) of 230 - 250 °C. In another embodiment, the article has a melting temperature (Tm) of 235 - 245 °C. In another embodiment, the article has a melting temperature (Tm) of 230 - 240 °C.

[0033] There is no restriction on the recycled polyethylene terephthalate (rPET) that can be used in the blend compositions of the present disclosure. In one embodiment, the rPET is mechanically recycled. In one embodiment, the rPET is made from chemically recycled monomers (made by any known depolymerization method). In one embodiment, the rPET may be slightly modified, such as with up to 5 mol% isophthalic acid and / or up to 5 mol% CHDM or other diols. In one embodiment, the recycled PET (rPET) can be almost any "waste" industrial PET or post-consumer PET. In one embodiment, the rPET that can be used in the blend compositions of the present disclosure can be post-consumer recycled PET. In one embodiment, the rPET is post-industrial recycled PET. In one embodiment, the rPET is post-consumer PET from soft drink bottles. In one embodiment, discarded PET fibers, discarded PET films, and low-quality PET polymers are also suitable sources of rPET. In one embodiment, the recycled PET substantially comprises PET, although other copolyesters may also be used, especially when they have a structure similar to PET, such as PET copolymers, etc. In one embodiment, the rPET is clean. In one embodiment, the rPET is substantially free of contaminants. In one embodiment, the rPET can be in the form of flakes.

[0034] In one embodiment, up to about 50 wt% rPET can be incorporated into the blend compositions of the present disclosure. In one embodiment, the rPET / copolyester blend is 15 - 50 wt% rPET. In one embodiment, the rPET / copolyester blend is 25 - 40 wt% recycled polyethylene terephthalate (rPET). In one embodiment, the rPET / copolyester blend is 20 - 30 wt% recycled polyethylene terephthalate (rPET). In one embodiment, the rPET / copolyester blend is 15 - 50 wt% recycled polyethylene terephthalate (rPET) and 50 - 85 wt% of at least one copolyester.

[0035] As used herein, the term "polyester" is intended to include "copolyester" and is understood to refer to a synthetic polymer made by the reaction of one or more difunctional carboxylic acids and / or polyfunctional carboxylic acids with one or more difunctional hydroxy compounds and / or polyfunctional hydroxy compounds, such as a branching agent. Generally, the difunctional carboxylic acid can be a dicarboxylic acid, and the difunctional hydroxy compound can be a dihydroxy alcohol, such as glycols and diols. As used herein, the term "glycol" includes, but is not limited to, diols, glycols, and / or polyfunctional hydroxy compounds, such as a branching agent. Alternatively, the difunctional carboxylic acid can be a hydroxycarboxylic acid, such as p-hydroxybenzoic acid, and the difunctional hydroxy compound can have an aromatic nucleus with 2 hydroxy substituents, such as hydroquinone. As used herein, the term "residue" refers to any organic structure incorporated into a polymer from the corresponding monomer by a polycondensation and / or esterification reaction. As used herein, the term "repeating unit" refers to an organic structure having a dicarboxylic acid residue and a glycol residue bonded via an ester group. Thus, for example, the dicarboxylic acid residue can be derived from a dicarboxylic acid monomer or its related acyl halide, ester, salt, anhydride, and / or mixtures thereof. In addition, as used herein, the term "diacid" includes polyfunctional acids, such as a branching agent. Thus, the term "dicarboxylic acid" as used herein is intended to include dicarboxylic acids and any derivatives of dicarboxylic acids that can be used in a reaction process for preparing a polyester with a diol, including its related acyl halide, ester, half-ester, salt, half-salt, anhydride, mixed anhydride, and / or mixtures thereof. As used herein, the term "terephthalic acid" is intended to include terephthalic acid itself and its residues that can be used in a reaction process for preparing a polyester with a diol, as well as any derivatives of terephthalic acid, including its related acyl halide, ester, half-ester, salt, half-salt, anhydride, mixed anhydride, and / or mixtures thereof or their residues.

[0036] The polyesters for the present disclosure can generally be prepared from dicarboxylic acids and diols that react substantially in equimolar proportions and are incorporated into the polyester polymer as the corresponding residues of the dicarboxylic acids and diols. The polyesters of the present disclosure can thus contain substantially equimolar proportions of acid residues (100 mol%) and diol (and / or polyfunctional hydroxy compound) residues (100 mol%) such that the total molar amount of the repeating units equals 100 mol%. Thus, the mole percentages provided in the present disclosure can be based on the total molar amount of the acid residues, the total molar amount of the diol residues, or the total molar amount of the repeating units. For example, a polyester containing 10 mol% isophthalic acid based on the total acid residues means that the polyester contains 10 mol% isophthalic acid residues in a total of 100 mol% acid residues. Thus, there are 10 moles of isophthalic acid residues per 100 moles of acid residues. In another example, a polyester containing 25 mol% 1,4-cyclohexanedimethanol based on the total diol residues means that the polyester contains 25 mol% 1,4-cyclohexanedimethanol residues in a total of 100 mol% diol residues. Thus, there are 25 moles of 1,4-cyclohexanedimethanol residues per 100 moles of diol residues.

[0037] In certain embodiments, terephthalic acid or its esters, such as dimethyl terephthalate or a mixture of terephthalic acid residues and their esters, can form part or all of the dicarboxylic acid component used to form the polyesters useful in the present disclosure. In certain embodiments, terephthalic acid residues can form part or all of the dicarboxylic acid component used to form the polyesters useful in the present disclosure. For the present disclosure, the terms "terephthalic acid" and "dimethyl terephthalate" can be used interchangeably herein. In one embodiment, dimethyl terephthalate is part or all of the dicarboxylic acid component used to make the polyesters useful in the present disclosure. In embodiments, a range of 70 to 100 mol%; or 80 to 100 mol%; or 90 to 100 mol%; or 99 to 100 mol%; or 100 mol% of terephthalic acid and / or dimethyl terephthalate and / or mixtures thereof can be used.

[0038] In addition to terephthalic acid, the dicarboxylic acid component that can be used for polyester of the present disclosure can include up to 30 mol %, up to 20 mol %, up to 10 mol %, up to 5 mol % or up to 1 mol % of one or more modified aromatic dicarboxylic acids.Another embodiment contains 0 mol % modified aromatic dicarboxylic acid.Therefore, if present, the amount of one or more modified aromatic dicarboxylic acids is expected to start from any of these aforementioned endpoint values, including, for example, 0.01 to 30 mol %, 0.01 to 20 mol %, 0.01 to 10 mol %, 0.01 to 5 mol % and 0.01 to 1 mol %.In one embodiment, the modified aromatic dicarboxylic acids that can be used for the present disclosure include but are not limited to those with up to 20 carbon atoms, and it can be linear, para-oriented or symmetrical. Examples of modified aromatic dicarboxylic acids useful in the present disclosure include, but are not limited to, isophthalic acid, 4,4′-biphenyl dicarboxylic acid, 1,4-, 1,5-, 2,6-, 2,7-naphthalene dicarboxylic acid, and trans-4,4′-stilbene dicarboxylic acid, and esters thereof. In one embodiment, the modified aromatic dicarboxylic acid is isophthalic acid.

[0039] The carboxylic acid component of the polyester useful in the present disclosure can be further modified with up to 30 mol%, up to 20 mol%, up to 10 mol%, up to 5 mol%, or up to 1 mol% of one or more aliphatic dicarboxylic acids containing 2-20 carbon atoms, such as cyclohexanedicarboxylic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, and / or dodecanedicarboxylic acid. Certain embodiments can also contain 0.01 to 30 mol%, 0.01 to 20 mol%, 0.01 to 10 mol%, such as 0.1 to 30 mol%, 1 to 30 mol%, 5 to 30 mol%, or 0.1 to 20 mol%, 1 to 20 mol%, 5 to 20 mol%, or 0.1 to 10 mol%, 1 or 10 mol%, 5 to 10 mol% of one or more modified aliphatic dicarboxylic acids. Yet another embodiment contains 0 mol% modified aliphatic dicarboxylic acids. The total mole % of the dicarboxylic acid component is 100 mole %. In one embodiment, adipic acid and / or glutaric acid are provided in the modifying aliphatic dicarboxylic acid component of the polyester and can be used in the present disclosure.

[0040] Can use esters of terephthalic acid and other modified dicarboxylic acids or their corresponding esters and / or salts to replace dicarboxylic acids. Suitable examples of dicarboxylic acid esters include but are not limited to dimethyl ester, diethyl ester, dipropyl ester, diisopropyl ester, dibutyl ester and diphenyl ester. In one embodiment, the ester is selected from at least one of the following: methyl ester, ethyl ester, propyl ester, isopropyl ester and phenyl ester.

[0041] In one embodiment, the diol component of the copolyester that can be used in the blend compositions of the present disclosure can include 1,4-cyclohexanedimethanol. In another embodiment, the diol component of the copolyester that can be used in the blend compositions of the present disclosure includes 1,4-cyclohexanedimethanol and 1,3-cyclohexanedimethanol. The molar ratio of cis / trans 1,4-cyclohexanedimethanol can be in the range of 50 / 50 to 0 / 100, for example, varying between 40 / 60 and 20 / 80.

[0042] In one embodiment, the diol component of the copolyester that can be used in the blend compositions of the present disclosure can include 2,2,4,4-tetramethyl-1,3-cyclobutanediol. In another embodiment, the molar ratio of cis / trans 2,2,4,4-tetramethyl-1,3-cyclobutanediol can vary from their respective pure forms to their mixtures. In certain embodiments, the molar percentage of cis and / or trans 2,2,4,4-tetramethyl-1,3-cyclobutanediol is more than 50 mole % cis and less than 50 mole % trans; or more than 55 mole % cis and less than 45 mole % trans; or 50 to 70 mole % cis and 50 to 30 mole % trans; or 60 to 70 mole % cis and 30 to 40 mole % trans; or more than 70 mole % cis and less than 30 mole % trans; wherein the total molar percentage of cis- and trans-2,2,4,4-tetramethyl-1,3-cyclobutanediol is equal to 100 mole %. In another embodiment, the molar ratio of cis / trans 2,2,4,4-tetramethyl-1,3-cyclobutanediol can be in the range of 50 / 50 to 0 / 100, for example, varying between 40 / 60 and 20 / 80.

[0043] In one embodiment, the total comonomer content from diols and acids other than ethylene glycol (EG), terephthalic acid (TPA) or dimethyl terephthalate (DMT) in the rPET / copolyester blend compositions that can be used in the present disclosure is 5 to 15 wt%, or 5 to 10 wt%, or 10 to 15 wt%, or 2 to 15 wt%, or 2 to 10 wt%, or 3 to 15 wt%, or 3 to 10 wt%, or 4 to 15 wt%, or 4 to 10 wt%, or 6 to 15 wt%, or 6 to 10 wt%, or 7 to 15 wt%, or 7 to 10 wt%, or 8 to 15 wt%, or 8 to 10 wt%, or 9 to 15 wt%, or 9 to 10 wt%, or 11 to 15 wt%, 12 to 15 wt%, or 13 to 15 wt%, 14 to 15 wt%, or 12 to 16 wt%.

[0044] In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 50 mol% of neopentyl glycol based on 100 mol% of the total diol component. In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 25 mol% of neopentyl glycol based on 100 mol% of the total diol component. In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 15 mol% of neopentyl glycol based on 100 mol% of the total diol component. In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 50 mol% of neopentyl glycol based on 100 mol% of the total diol component. In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 5 to 50 mol% of neopentyl glycol based on 100 mol% of the total diol component. In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 10 to 30 mol% of neopentyl glycol based on 100 mol% of the total diol component. In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 10 to 15 mol% of neopentyl glycol based on 100 mol% of the total diol component. In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 15 to 45 mol% of neopentyl glycol.

[0045] In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 50 mol%, or 0 to 40 mol%, or 0 to 30 mol%, or 0 to 20 mol%, or 0 to 10 mol%, or 0.01 to 50 mol%, or 0.01 to 40 mol%, or 0.01 to 30 mol%, or 0.01 to 20 mol%, or 0.01 to 15 mol%, or 0.01 to 14 mol%, or 0.01 to 13 mol%, or 0.01 to 12 mol%, or 0.01 to 11 mol%, or 0.01 to 10 mol%, or 0.01 to 9 mol%, or 0.01 to 8 mol%, or 0.01 to 7 mol%, or 0.01 to 6 mol%, or 0.01 to 5 mol%, or 0.1 to 50 mol%, or 0.1 to 40 mol%, or 0.1 to 30 mol%, or 0.1 to 20 mol%, or 0.1 to 10 mol%, or 5 to 50 mol%, 10 to 50 mol%, or 20 to 50 mol%, or 30 to 50 mol%, or 40 to 50 mol%, or 20 to 40 mol%, or 30 to 40 mol%, or 10 to 40 mol%, 10 to 30 mol%, or 10 to 20 mol%, or 20 to 30 mol%, or 2 to 50 mol%, or 2 to 40 mol%, or 2 to 30 mol%, or 2 to 20 mol%, 3 to 15 mol%, or 3 to 14 mol%, or 3 to 13 mol%, or 3 to 12 mol%, or 3 to 11 mol%, or 3 to 10 mol%, or 3 to 9 mol%, or 3 to 8 mol%, or 3 to 7 mol%, or 2 to 10 mol%, or 2 to 9 mol%, or 2 to 8 mol%, or 2 to 7 mol%, or 2 to 5 mol%, or 1 to 7 mol%, or 1 to 5 mol%, or 1 to 3 mol% of neopentyl glycol residues, based on 100 mol% of the total diol component.

[0046] In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 50 mol% of 1,4-cyclohexanedimethanol based on 100 mol% of the total mol% of the diol component. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0.01 to less than 50 mol% of 1,4-cyclohexanedimethanol based on 100 mol% of the total mol% of the diol component. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0 to 15 mol% of 1,4-cyclohexanedimethanol based on 100 mol% of the total mol% of the diol component. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0.01 to less than 15 mol% of 1,4-cyclohexanedimethanol based on 100 mol% of the total mol% of the diol component. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0.01 to 5 mol% of 1,4-cyclohexanedimethanol based on 100 mol% of the total mol% of the diol component. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0 to less than 5 mol% of 1,4-cyclohexanedimethanol based on 100 mol% of the total mol% of the diol component.

[0047] In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 50 mole percent, or from 0 to 40 mole percent, or from 0 to 30 mole percent, or from 0 to 20 mole percent, or from 0 to 10 mole percent, or from 0.01 to 50 mole percent, or from 0.01 to 40 mole percent, or from 0.01 to 30 mole percent, or from 0.01 to 20 mole percent, or from 0.01 to 15 mole percent, or from 0.01 to 14 mole percent, or from 0.01 to 13 mole percent, or from 0.01 to 12 mole percent, or from 0.01 to 11 mole percent, or from 0.01 to 10 mole percent, or from 0.01 to 9 mole percent, or from 0.01 to 8 mole percent, or from 0.01 to 7 mole percent, or from 0.01 to 6 mole percent, or from 0.01 to 5 mole percent, or from 0.1 to 50 mole percent, or from 0.1 to 40 mole percent, or from 0.1 to 30 mole percent, or from 0.1 to 20 mole percent, or from 0.1 to 10 mole percent, or from 5 to 50 mole percent, 10 to 50 mole percent, or 20 to 50 mole percent, or 30 to 50 mole percent, or 40 to 50 mole percent, or 20 to 40 mole percent, or 30 to 40 mole percent, or 10 to 40 mole percent, 10 to 30 mole percent, or 10 to 20 mole percent, or 20 to 30 mole percent, or from 2 to 50 mole percent, or from 2 to 40 mole percent, or from 2 to 30 mole percent, or from 2 to 20 mole percent, from 3 to 15 mole percent, or from 3 to 14 mole percent, or from 3 to 13 mole percent, or from 3 to 12 mole percent, or from 3 to 11 mole percent, or from 3 to 10 mole percent, or from 3 to 9 mole percent, or from 3 to 8 mole percent, or from 3 to 7 mole percent, or from 2 to 10 mole percent, or from 2 to 9 mole percent, or from 2 to 8 mole percent, or from 2 to 7 mole percent, or from 2 to 5 mole percent, or from 1 to 7 mole percent, or from 1 to 5 mole percent, or from 1 to 3 mole percent of 1,4-cyclohexanedimethanol residues, based on 100 mole percent of the diol component.

[0048] In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure can contain from 0 to 35 mol%, or 0 to 30 mol%, or 0 to 25 mol%, or 0 to 20 mol%, or 0 to 10 mol%, or 0.01 to 35 mol%, or 0.01 to 30 mol%, or 0.01 to 25 mol%, or 0.01 to 20 mol%, or 0.01 to 15 mol%, or 0.01 to 14 mol%, or 0.01 to 13 mol%, or 0.01 to 12 mol%, or 0.01 to 11 mol%, or 0.01 to 10 mol%, or 0.01 to 9 mol%, or 0.01 to 8 mol%, or 0.01 to 7 mol%, or 0.01 to 6 mol%, or 0.01 to 5 mol%, or 0.1 to 35 mol%, or 0.1 to 30 mol%, or 0.1 to 25 mol%, or 0.1 to 20 mol%, or 0.1 to 10 mol%, or 5 to 35 mol%, 10 to 35 mol%, or 20 to 35 mol%, or 25 to 35 mol%, 10 to 30 mol%, or 10 to 20 mol%, or 20 to 30 mol%, or 2 to 35 mol%, or 2 to 25 mol%, or 2 to 30 mol%, or 2 to 20 mol%, 3 to 15 mol%, or 3 to 14 mol%, or 3 to 13 mol%, or 3 to 12 mol%, or 3 to 11 mol%, or 3 to 10 mol%, or 3 to 9 mol%, or 3 to 8 mol%, or 3 to 7 mol%, or 2 to 10 mol%, or 2 to 9 mol%, or 2 to 8 mol%, or 2 to 7 mol%, or 2 to 5 mol%, or 1 to 7 mol%, or 1 to 5 mol%, or 1 to 3 mol% of 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues, based on 100 mol% of the total diol component.

[0049] In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend composition of the present disclosure may contain from 0 to 35 mol%, based on 100 mol% of the total mol% of the diol component, of 2,2,4,4-tetramethyl-1,3-cyclobutanediol. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0.01 to less than 35 mol%, based on 100 mol% of the total mol% of the diol component, of 2,2,4,4-tetramethyl-1,3-cyclobutanediol. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0 to 30 mol%, based on 100 mol% of the total mol% of the diol component, of 2,2,4,4-tetramethyl-1,3-cyclobutanediol. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0.01 to less than 30 mol%, based on 100 mol% of the total mol% of the diol component, of 2,2,4,4-tetramethyl-1,3-cyclobutanediol. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0.01 to 25 mol%, based on 100 mol% of the total mol% of the diol component, of 2,2,4,4-tetramethyl-1,3-cyclobutanediol. In one embodiment, the diol component of the copolyester composition that can be used in the present disclosure may contain from 0 to less than 25 mol%, based on 100 mol% of the total mol% of the diol component, of 2,2,4,4-tetramethyl-1,3-cyclobutanediol.

[0050] It should be understood that some other diol residues may be formed in situ during processing. For example, in one embodiment, the total amount of diethylene glycol residues present in the copolyester that can be used in the present disclosure (whether formed in situ during processing or intentionally added or both) can be any amount, such as from 1 to 15 mol%, or 2 to 12 mol%, or 2 to 11 mol%, or 2 to 10 mol%, or 2 to 9 mol%, or 3 to 12 mol%, or 3 to 11 mol%, or 3 to 10 mol%, or 3 to 9 mol%, or 4 to 12 mol%, or 4 to 11 mol%, or 4 to 10 mol%, or 4 to 9 mol%, or 5 to 12 mol%, or 5 to 11 mol%, or 5 to 10 mol%, or 5 to 9 mol% of diethylene glycol residues, based on 100 mol% of the total mol% of the diol component.

[0051] In one embodiment, the total amount of diethylene glycol (DEG) residues present in the copolyesters useful in the present disclosure (whether formed in situ during processing or intentionally added or both) can be 5 mole % or less, or 4 mole % or less, or 3.5 mole % or less, or 3.0 mole % or less, or 2.5 mole % or less, or 2.0 mole % or less, or 1.5 mole % or less, or 1.0 mole % or less, or 1 to 4 mole %, or 1 to 3 mole %, or 1 to 2 mole % of diethylene glycol residues, based on 100 mole % of the total molar % of the glycol component, or 2 to 8 mole %, or 2 to 7 mole %, or 2 to 6 mole %, or 2 to 5 mole %, or 3 to 8 mole %, or 3 to 7 mole %, or 3 to 6 mole %, or 3 to 5 mole %, or in some embodiments, no intentionally added diethylene glycol residues. In certain embodiments, the copolyester does not contain added modified glycols. In certain embodiments, the diethylene glycol residues in the copolyester can be 5 mole % or less. It should be noted that any low levels of DEG formed in situ are not included in the total comonomer content from glycols and acids other than EG, TPA or DMT.

[0052] For all embodiments, the remaining glycol component can contain any amount of ethylene glycol residues, based on 100 mole % of the total molar % of the glycol component. In one embodiment, the copolyesters useful in the present disclosure can contain 50 mole % or more, or 55 mole % or more, or 60 mole % or more, or 65 mole % or more, or 70 mole % or more, or 75 mole % or more, or 80 mole % or more, or 85 mole % or more, or 90 mole % or more, or 95 mole % or more, or 98 mole % or more, or 50 to 90 mole %, or 55 to 90 mole %, or 50 to 80 mole %, or 55 to 80 mole %, or 60 to 80 mole %, or 50 to 75 mole %, or 55 to 75 mole %, or 60 to 75 mole %, or 65 to 75 mole % of ethylene glycol residues, based on 100 mole % of the total molar % of the glycol component.

[0053] In one embodiment, the diol component of the copolyester that can be used in the rPET / copolyester blend compositions of the present disclosure can contain up to 35 mol%, up to 30 mol%, up to 25 mol%, up to 20 mol%, or up to 19 mol%, or up to 18 mol%, or up to 17 mol%, or up to 16 mol%, or up to 15 mol%, or up to 14 mol%, or up to 13 mol%, or up to 12 mol%, or up to 11 mol%, or up to 10 mol%, or up to 9 mol%, or up to 8 mol%, or up to 7 mol%, or up to 6 mol%, or up to 5 mol%, or up to 4 mol%, or up to 3 mol%, or up to 2 mol%, or up to 1 mol% or less of one or more other modified diols (other modified diols are defined as diols that are not ethylene glycol, diethylene glycol, neopentyl glycol, 1,4-cyclohexanedimethanol, or 2,2,4,4-tetramethyl-1,3-cyclobutanediol). In certain embodiments, the copolyester that can be used in the present disclosure can contain 35 mol% or less of one or more other modified diols; 30 mol% or less of one or more other modified diols; 25 mol% or less of one or more other modified diols; 20 mol% or less of one or more other modified diols; 15 mol% or less of one or more other modified diols; 10 mol% or less of one or more other modified diols. In certain embodiments, the copolyester that can be used in the present disclosure can contain 5 mol% or less of one or more other modified diols. In certain embodiments, the copolyester that can be used in the present disclosure can contain 3 mol% or less of one or more other modified diols. In another embodiment, the copolyester that can be used in the present disclosure can contain 0 mol% of other modified diols. However, it is expected that some other diol residues can be formed in situ such that the in situ formed residual amount is also an embodiment of the present disclosure.

[0054] In an embodiment, other modified diols (if used) as defined herein for the copolyester contain 2 to 16 carbon atoms. Examples of other modified diols include but are not limited to 1,2-propanediol, 1,3-propanediol, isosorbide, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, p-xylene glycol, polytetramethylene glycol, and mixtures thereof. In one embodiment, isosorbide is the other modified diol. In another embodiment, the other modified diols include but are not limited to at least one of 1,3-propanediol and 1,4-butanediol. In one embodiment, 1,3-propanediol and / or 1,4-butanediol can be excluded. If 1,4- or 1,3-butanediol is used, in one embodiment more than 4 mol% or more than 5 mol% can be provided. In one embodiment, at least one other modified diol is 1,4-butanediol present in an amount of 5 to 35 mol%.

[0055] In some embodiments, the copolyester compositions according to the present disclosure may comprise from 0 to 10 mole percent, such as from 0.01 to 5 mole percent, from 0.01 to 1 mole percent, from 0.05 to 5 mole percent, from 0.05 to 1 mole percent, or from 0.1 to 0.7 mole percent, or from 0.05 to 2.0 mole percent, 0,05 to 1.5 mole percent, 0.05 to 1.0 mole percent, 0.05 to 0.8 mole percent, 0.05 to 0.6 mole percent, 0.1 to 2.0 mole percent, 0.1 to 1.5 mole percent, 0.1 to 1.0 mole percent, 0.1 to 0.8 mole percent, 0.1 to 0.6 mole percent, 0.2 to 2.0 mole percent, 0.2 to 1.5 mole percent, 0.2 to 1.0 mole percent, 0.2 to 0.8 mole percent, 0.2 to 0.6 mole percent, 0.3 to 2.0 mole percent, 0.3 to 1.5 mole percent, 0.3 to 1.0 mole percent, 0.3 to 0.8 mole percent, 0.3 to 0.6 mole percent, 0.5 to 2.0 mole percent, 0.5 to 1.5 mole percent, 0.5 to 1.0 mole percent, or 0.5 to 0.8 mole percent, based on the total mole percent of diol or diacid residues, of one or more branching monomer residues having three or more carboxyl substituents, hydroxyl substituents, or a combination thereof (also referred to herein as branching agents). In certain embodiments, the branching monomer or branching agent may be added before and / or during and / or after the polymerization of the copolyester. In some embodiments, one or more copolyesters useful in the present disclosure may thus be linear or branched.

[0056] Examples of branching monomers include, but are not limited to, polyfunctional acids or polyfunctional alcohols such as trimellitic acid, trimellitic anhydride, pyromellitic dianhydride, trimethylolpropane, glycerol, pentaerythritol, citric acid, tartaric acid, 3-hydroxyglutaric acid, etc. In one embodiment, the branching monomer residues may comprise from 0.1 to 0.7 mole percent of one or more residues selected from at least one of the following: trimellitic anhydride, pyromellitic dianhydride, glycerol, sorbitol, 1,2,6-hexanetriol, pentaerythritol, trimethylolethane, and / or trimellitic acid. The branching monomer may be added to the copolyester reaction mixture in concentrate form or blended with the copolyester as described, for example, in U.S. Patent Nos. 5,654,347 and 5,696,176, the disclosures of which regarding the branching monomer are incorporated herein by reference.

[0057] In one embodiment, the branching monomer or branching agent useful for preparing the copolyesters formed in the context of the present disclosure can be a branching monomer or branching agent that provides branching in the acid unit portion or in the diol unit portion of the copolyester, or it can be a hybrid. In some embodiments, some examples of branching agents are polyfunctional acids, polyfunctional anhydrides, polyfunctional diols, and acid / diol hybrids. Examples include tri- or tetracarboxylic acids and their corresponding anhydrides, such as trimellitic acid, pyromellitic acid, and their lower carbon alkyl esters, etc., and tetraols, such as pentaerythritol. Triols such as trimethylolpropane or dihydroxycarboxylic acids and hydroxy dicarboxylic acids and derivatives, such as dimethyl hydroxyterephthalate, etc. can also be used in the context of the present disclosure. In one embodiment, trimellitic anhydride is the branching monomer or branching agent.

[0058] The copolyester composition useful for the present disclosure can comprise at least one chain extender. Suitable chain extenders include, but are not limited to, polyfunctional (including but not limited to bifunctional) isocyanates, polyfunctional epoxides, including for example epoxidized novolak resins and phenoxy resins. In one embodiment, the chain extender has an epoxide dependent group. In one embodiment, the chain extending additive can be one or more styrene-acrylate copolymers having an epoxy functional group. In one embodiment, the chain extending additive can be one or more copolymers of glycidyl methacrylate and styrene.

[0059] In certain embodiments, the chain extender can be added at the end of the polymerization process or after the polymerization process. If added after the polymerization process, it can be incorporated by compounding or by addition during a conversion process, such as an injection molding or extrusion process. In certain embodiments, the chain extender can be added to rPET, added to the copolyester, or added to the blend during or after the blending process. In some embodiments, it can be incorporated by compounding or by addition during a conversion process, such as an injection molding or extrusion process.

[0060] The amount of chain extender used can vary depending on the specific monomer composition used and the desired physical properties, but is typically from about 0.05 wt% to about 10 wt% based on the total weight of the rPET / copolyester blend composition, such as from about 0.1 to about 10 wt% or 0.1 to about 5 wt%, 0.1 to about 2 wt%, or 0.1 to about 1 wt% based on the total weight of the copolyester blend composition. In one embodiment, the copolyester composition comprises 0.05 to 5 wt% of chain extender based on the total weight of the rPET / copolyester blend composition.

[0061] In some embodiments, chain extenders can also be added during melt processing to build molecular weight by "reactive extrusion" or "reactive chain coupling" or any other process known in the art.

[0062] In one embodiment, certain copolyester blend compositions useful in the present disclosure can exhibit a melt viscosity (MV) at a shear rate of 1 radian / second greater than 10,000 poise, or greater than 20,000 poise, or greater than 30,000 poise, or greater than 40,000 poise, or greater than 50,000 poise, or greater than 60,000 poise, or greater than 70,000 poise, or greater than 80,000 poise, or greater than 90,000 poise, or greater than 100,000 poise, where the melt viscosity is measured using a rotational viscometer, such as a Rheometrics Dynamic Analyzer (RDA II) at 260 °C and 1 radian / second. In one embodiment, certain copolyester blend compositions useful in the present disclosure can exhibit a melt viscosity (MV) at a shear rate of 1 radian / second of from 10,000 poise to 120,000 poise, or from 20,000 poise to 80,000 poise, where the melt viscosity is measured using a rotational viscometer, such as a Rheometrics Dynamic Analyzer (RDA II) at 260 °C and 1 radian / second.

[0063] Unless otherwise specified, copolyester compositions useful in the present disclosure are expected to have at least one intrinsic viscosity range as described herein and at least one monomer range of the copolyester compositions as described herein. Unless otherwise specified, copolyester compositions useful in the present disclosure are further expected to have at least one Tg range as described herein and at least one monomer range of the copolyester compositions as described herein. Unless otherwise specified, copolyester compositions useful in the present disclosure are further expected to have at least one intrinsic viscosity range as described herein, at least one Tg range as described herein, and at least one monomer range of the copolyester compositions as described herein.

[0064] For embodiments of the present disclosure, the copolyester compositions useful in the present disclosure may exhibit at least one of the following intrinsic viscosities as measured at 25 °C at a concentration of 0.25 g / 50 ml in 60 / 40 (wt / wt) phenol / tetrachloroethane: 0.50 to 1.2 dL / g; 0.50 to 1.0 dL / g; 0.50 to 0.90 dL / g; 0.50 to 0.80 dL / g; 0.55 to 1.2 dL / g; 0.55 to 1.0 dL / g; 0.55 to 0.90 dL / g; 0.55 to 0.80 dL / g; 0.58 to 1.2 dL / g; 0.58 to 1.0 dL / g; 0.58 to 0.90 dL / g; 0.58 to 0.80 dL / g; 0.60 to 0.90 dL / g; 0.60 to 0.80 dL / g; 0.65 to 0.90 dL / g; 0.60 to 0.80 dL / g; 0.70 to 0.80 dL / g; 0.50 to 0.75 dL / g; 0.55 to 0.75 dL / g; 0.58 to 0.75 dL / g; 0.60 to 0.75 dL / g; 0.60 to 0.70 dL / g; 0.58 to 0.70 dL / g; or 0.55 to 0.70 dL / g.

[0065] The glass transition temperature (Tg) of the copolyester of the rPET / copolyester blend composition was measured using a TA DSC 2920 from Thermal Analyst Instrument at a scan rate of 20 °C / min. The value of the glass transition temperature was measured during the second heating.

[0066] In certain embodiments, the molded articles of the present disclosure comprise an rPET / copolyester blend composition, wherein the copolyester has a Tg of 70 to 115 °C; 70 to 80 °C; 70 to 85 °C; or 70 to 90 °C; or 70 to 95 °C; 70 to 100 °C; 70 to 105 °C; 70 to 110 °C; 80 to 115 °C; 80 to 85 °C; or 80 to 90 °C; or 80 to 95 °C; 80 to 100 °C; 80 to 105 °C; 80 to 110 °C; 90 to 115 °C; 90 to 100 °C; 90 to 105 °C; 90 to 110 °C.

[0067] In one embodiment, the rPET / copolyester blend compositions useful in the present disclosure are clear or visually clear. The term "visually clear" is defined herein as being visibly free of cloudiness, haziness, and / or muddiness upon visual inspection. In one embodiment, the rPET / copolyester blend compositions useful in the present disclosure are transparent. The term "transparent" is defined herein as being visibly free of cloudiness, haziness, and / or muddiness such that the material can be seen through upon visual inspection. These terms are used interchangeably herein. In one aspect, the terms clear and / or transparent are defined as having a low haze. In one embodiment, clear and / or transparent is defined as having a haze value of 20% or less. In one embodiment, clear and / or transparent is defined as having a haze value of 15% or less. In one embodiment, clear and / or transparent is defined as having a haze value of 12% or less. In one embodiment, clear and / or transparent is defined as having a haze value of 10% or less. In one embodiment, clear and / or transparent is defined as having a haze value of 5% or less.

[0068] Any amorphous or substantially amorphous copolyester is suitable for use in the present disclosure. In one embodiment, the copolyester of the present disclosure is amorphous. In one embodiment, the copolyester of the present disclosure is amorphous or slowly crystallizing. In one embodiment, the copolyester of the present disclosure is substantially amorphous. In one embodiment, any copolyester may be used in the present disclosure so long as they are substantially amorphous and have a minimum half-crystallization time of at least about 10 minutes or greater. In one embodiment, the copolyester of the present disclosure has a half-crystallization time of at least about 20 minutes or greater. The half-crystallization time can be, for example, at least 30 minutes or greater, at least 50 minutes or greater, at least 60 minutes or greater. The amorphous copolyesters in the present disclosure can have a half-crystallization time up to infinity in some embodiments.

[0069] The rPET / copolyester blends in the present disclosure crystallize rapidly to render them compatible with PET recycling processes. For example, in one embodiment, the rPET / copolyester blend has a half-crystallization time of from about 1 minute to about 20 minutes. For example, in another embodiment, the rPET / copolyester blend has a half-crystallization time of from about 3 minutes to about 20 minutes. In one embodiment, the rPET / copolyester blend has a half-crystallization time of at most about 20 minutes, or at most about 15 minutes or at most about 10 minutes or at most about 5 minutes. In one embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is about 3 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is about 5 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is about 10 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is about 15 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is about 20 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is less than about 20 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is less than about 15 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is less than about 10 minutes. In another embodiment, an rPET / copolyester blend can be used so long as its half-crystallization time is less than about 5 minutes.

[0070] The half-crystallization time of the copolyesters or rPET / copolyester blends as used herein can be measured using conventional methods. For example, in one embodiment, a differential scanning calorimeter (DSC) is used to measure the half-crystallization time. In these cases, the sample is ramped (20 °C / min) to 285 °C and held isothermally for 2 minutes. Subsequently, the polymer is rapidly dropped to a set-point temperature (180 °C) and held until crystallization is complete, as indicated by a fully endothermic heat flow curve. The half-crystallization time is reported as the time from the start of crystallization to half of the peak formation.

[0071] In one embodiment, the copolyester can be produced by a method in a homogeneous solution, by a transesterification method in the melt, and by a two-phase interfacial method. Suitable methods include, but are not limited to, the step of reacting one or more dicarboxylic acids with one or more diols at a temperature of 100°C to 315°C and a pressure of 0.1 to 760 mm Hg for a time sufficient to form the copolyester. Regarding the method for producing copolyesters, see U.S. Patent No. 3,772,405, the disclosure of which is hereby incorporated by reference. In one embodiment, the copolyester can be made from chemically recycled monomers (made by any known depolymerization method).

[0072] As described in more detail in U.S. Patent No. 2,720,507, which is incorporated herein by reference, the copolyester can generally be prepared by condensing a dicarboxylic acid or a dicarboxylic acid ester with a diol in an inert atmosphere in the presence of a catalyst at an elevated temperature (which is gradually increased to a temperature of up to about 225°C to 310°C during the condensation process) and carrying out the condensation at a low pressure in the later stage of the condensation.

[0073] In some embodiments, during the process of making the copolyester that can be used in the present disclosure, certain reagents that color the polymer can be added to the melt, including toners or dyes. In one embodiment, a bluing toner is added to the melt to reduce the b* of the resulting copolyester polymer melt phase product. Such bluing agents include one or more inorganic and organic blue toners and / or dyes. In addition, one or more red toners and / or dyes can also be used to adjust the a* color. One or more organic toners can be used, such as one or more organic toners of blue and red, such as those described in U.S. Patent Nos. 5,372,864 and 5,384,377 (which are incorporated by reference in their entirety). One or more organic toners can be fed as a premixed composition. The premixed composition can be a pure blend of red and blue compounds, or the composition can be pre-dissolved or slurried in one of the raw materials of the copolyester, such as ethylene glycol.

[0074] The total amount of the added toner components can depend on the amount of yellow inherent in the base copolyester and the potency of the toner. In one embodiment, a combined organic toner component concentration of up to about 15 ppm can be used, and a minimum concentration of about 0.5 ppm. In one embodiment, the total amount of the bluing additive can be 0.5 to 10 ppm. In one embodiment, one or more toners can be added to the esterification zone or the polycondensation zone. It is preferred to add one or more toners to the esterification zone or to the early stage of the polycondensation zone, such as adding to a prepolymer reactor.

[0075] The rPET / copolyester blend composition can be prepared by conventional processing techniques known in the art, such as melt blending, melt mixing, compounding by single-screw extrusion, compounding by twin-screw extrusion, batch melt mixing equipment, or combinations of the above. In one embodiment, the rPET / copolyester blend composition is compounded at a temperature of 220 - 320 °C. In one embodiment, the rPET / copolyester blend composition is compounded at a temperature of 220 - 300 °C. In one embodiment, the rPET / copolyester blend components can be pre-dried at 60 - 160 °C. In one embodiment, the rPET / copolyester blend components are not pre-dried. In one embodiment, the compounding can be carried out under vacuum. In one embodiment, the compounding is not carried out under vacuum.

[0076] In some embodiments, the rPET / copolyester blend copolyester composition can also contain amounts of common additives required for the intended application. In some embodiments, the rPET / copolyester blend copolyester composition can contain from 0.01 to 25 wt% or from 0.01 to 10 wt% of the total composition of common additives such as colorants, one or more toners, dyes, mold release agents, flame retardants, extenders, reinforcing agents or materials, fillers, antistatic agents, antimicrobial agents, antifungal agents, self-cleaning or low surface energy agents, scents or fragrances, antioxidants, extrusion aids, slip agents, release agents, carbon black and other pigments, plasticizers, glass bubbles, nucleating agents, stabilizers including but not limited to UV stabilizers, heat stabilizers and / or their reaction products, fillers and impact modifiers, etc., and mixtures thereof, which are known in the art for their utility in copolyester blends. Examples of commercially available impact modifiers include but are not limited to ethylene / propylene terpolymers, functionalized polyolefins such as those containing methyl acrylate and / or glycidyl methacrylate, styrene-based block copolymer impact modifiers, and various acrylic core / shell type impact modifiers. Residues of these additives are also expected to be part of the copolyester composition.

[0077] Reinforcing materials can be added to the compositions useful in the present disclosure. The reinforcing materials can include but are not limited to carbon filaments, silicates, mica, clay, talc, titanium dioxide, wollastonite, glass flakes, glass beads and fibers, and polymer fibers and combinations thereof. In one embodiment, the reinforcing material includes glass, such as fiberglass filaments, mixtures of glass and talc, mixtures of glass and mica, and mixtures of glass and polymer fibers.

[0078] In one aspect of the present disclosure, the rPET / copolyester blend composition of the present disclosure can be used as one or more films and / or one or more sheets that are thermoformable and / or heat formable. The present disclosure also relates to a manufactured article incorporating one or more thermoformed films and / or one or more sheets of the present disclosure. In one embodiment, the rPET / copolyester blend composition of the present disclosure can be used as films and sheets that are easily formed into formed articles or molded articles. In one embodiment, one or more films and / or one or more sheets of the present disclosure can be thermoformed into molded articles or components. The rPET / copolyester blend composition of the present disclosure can be used in a variety of molding and extrusion applications.

[0079] One aspect of the present disclosure is a method of using thermoforming to manufacture molded or formed components and articles. Any thermoforming technique or method known to those skilled in the art can be used to produce the molded or formed articles of the present disclosure.

[0080] In one embodiment, the films and sheets for use in the molding or thermoforming process can be made by any conventional method known to those skilled in the art. In one embodiment, the sheet or film is formed by extrusion. In one embodiment, the sheet or film is formed by calendering.

[0081] In one embodiment, the heat-set component can be ejected from the mold cavity by known ejection means. For example, in one embodiment, reverse blowing is used and it involves disrupting the vacuum established between the mold and the formed film or sheet by introducing compressed air. In some embodiments, the molded article or component is subsequently trimmed, and the scrap is ground and recycled.

[0082] In one embodiment, the compositions of the present disclosure can be used as plastics, films, fibers, and sheets. The compositions of the present disclosure can be used as molded or formed articles, molded or formed parts, or solid plastic objects. In one embodiment, the compositions of the present disclosure can be used as molded parts or molded articles. The compositions are suitable for any application that requires a clear rigid plastic. Examples of such parts and articles include tableware, disposable tableware, tableware handles, disposable knives, forks, spoons, plates, cups, straws, cans, cosmetic packaging, caps, decorative caps, personal care product packaging, eyeglass frames, ophthalmic lenses, toothbrushes, toothbrush handles, toys, utensils, tools, tool handles, camera parts, parts of electronic devices, razor parts, ink pen barrels, disposable syringes, bottles, bottle caps, shelves, shelf spacers, electronic device housings, electronic device cases, computer monitors, printers, keyboards, pipes, automotive parts, automotive interior parts, automotive trim, signs, outdoor signs, skylights, thermoformed letters, siding, toys, toy parts, thermally conductive plastics, medical devices, dental trays, dental appliances, containers, food containers, shipping containers, packaging, furniture components, multiwall films, multilayer films, insulation parts, insulation products, insulated containers, trays, food trays, food plates, drums, storage bins, food processors, blender and mixer bowls, water bottles, fry pans, washing machine parts, refrigerator parts, vacuum cleaner parts, thermally conductive plastics, health care products, commercial foodservice products, boxes, films for graphic arts applications, plastic films for plastic-glass laminates, point-of-purchase displays, exhaust vents, laminated cards, window and door layouts, insulated glass, spacers, ceiling panels, lighting fixtures, machine guards, graphic arts, lenses, extruded laminated sheets or films, decorative laminates, office furniture, face masks, medical packaging, signholders on point of display shelving, and shelf price holds, etc.

[0083] The present disclosure further relates to a manufactured article comprising one or more films and / or one or more sheets containing the rPET / copolyester blend compositions described herein. In an embodiment, the films and / or sheets of the present disclosure can be of any thickness required for the intended application.

[0084] The present disclosure further relates to one or more films and / or one or more sheets described herein. The method of forming the rPET / copolyester blend composition into one or more films and / or one or more sheets includes any method known in the art. Examples of one or more films and / or one or more sheets of the present disclosure include, but are not limited to, extruded one or more films and / or one or more sheets, calendered one or more films and / or one or more sheets, compression molded one or more films and / or one or more sheets, and methods of making films and / or sheets include, but are not limited to, extrusion, calendering, and compression molding.

[0085] The present disclosure further relates to molded or formed articles described herein. The method of forming the rPET / copolyester blend composition into a molded or formed article includes any known method in the art. Examples of the molded or formed articles of the present disclosure include, but are not limited to, thermoformed or thermoformable articles, injection molded articles, extrusion molded articles, injection blow molded articles, injection stretch blow molded articles, and extrusion blow molded articles. Methods of making molded articles include, but are not limited to, thermoforming, injection molding, extrusion, injection blow molding, injection stretch blow molding, and extrusion blow molding. The methods of the present disclosure may include any thermoforming method known in the art. The methods of the present disclosure may include any blow molding method known in the art, including, but not limited to, extrusion blow molding, extrusion stretch blow molding, injection blow molding, and injection stretch blow molding.

[0086] The present disclosure includes any injection blow molding manufacturing method known in the art. Although not limited thereto, a typical description of an injection blow molding (IBM) manufacturing method includes: 1) melting the composition in a reciprocating screw extruder; 2) injecting the molten composition into an injection mold to form a partially cooled tube closed at one end (i.e., a preform); 3) moving the preform into a blow mold surrounding the preform and having the desired finished shape, and closing the blow mold surrounding the preform; 4) blowing air into the preform to stretch and expand the preform to fill the mold; 5) cooling the molded article; 6) ejecting the article from the mold.

[0087] The present disclosure includes any injection stretch blow molding manufacturing method known in the art. Although not limited thereto, a typical description of an injection stretch blow molding (ISBM) manufacturing method includes: 1) melting the composition in a reciprocating screw extruder; 2) injecting the molten composition into an injection mold to form a partially cooled tube closed at one end (i.e., the preform); 3) moving the preform into a blow mold surrounding the preform and having the desired finished shape, and closing the blow mold surrounding the preform; 4) stretching the preform using an internal stretching rod and blowing air into the preform to stretch and expand the preform to fill the mold; 5) cooling the molded article; 6) ejecting the article from the mold.

[0088] The present disclosure includes any extrusion blow molding manufacturing method known in the art. Although not limited thereto, a typical description of an extrusion blow molding manufacturing method includes: 1) melting the composition in an extruder; 2) extruding the molten composition through a die to form a tube of molten polymer (i.e., a parison); 3) closing a mold having the desired finished shape around the parison; 4) blowing air into the parison to stretch and expand the extrudate to fill the mold; 5) cooling the molded article; 6) ejecting the article from the mold; and 7) removing excess plastic (commonly referred to as flash) from the article.

[0089] In one embodiment, the molded articles and components of the present disclosure can be of any thickness required for the intended end-use application. In one embodiment, the molded articles and components of the present disclosure have a thickness greater than about 4 mm. In one embodiment, the thickness of the molded articles and components is about 4 - 25 mm. In one embodiment, the thickness of the molded articles and components is about 7 - 25 mm. In one embodiment, the thickness of the molded articles and components is about 10 - 20 mm.

[0090] The following examples further illustrate how the rPET / copolyester blend compositions of the present disclosure can be prepared and evaluated, and they are intended to be exemplary only and not to limit their scope. Unless otherwise specified, parts are parts by weight, temperatures are in °C (degrees Celsius) or at room temperature, and pressures are equal to or near atmospheric pressure. Examples

[0091] The present disclosure can be further illustrated by the following examples of its preferred embodiments, but it is understood that these examples are included for illustrative purposes only and are not intended to limit the scope of the present disclosure unless otherwise expressly specified.

[0092] Description of Materials & Test Methods Materials for compounding: Table 1 is a summary of the various copolyester resins used to compound the blend compositions. Sample C31 and Sample E31 are amorphous copolyester materials modified with 31 mol% (15.9 wt%) from 1,4-cyclohexanedimethanol (CHDM) but having different intrinsic viscosities (IhV). Sample E4 is a semi-crystalline copolyester material with a lower CHMD modification of 4.5 mol% CHDM. Sample E12 is a semi-crystalline copolyester material with 12 mol% CHDM. Sample C50 has the highest CHDM loading, 50 mol%. Sample G23 material is another amorphous copolyester material modified with 23 mol% (12.1 wt%) from 2,2,4,4-tetramethyl-1,3-cyclobutanediol (TMCD). In all cases, the acid component is from dimethyl terephthalate (DMT) and the primary diol is ethylene glycol (EG). These resin samples are available from Eastman Chemical Company.

[0093] A blended blend composition is made using recycled PET from two sources (clean and clear bottle flakes). rPET1 is supplied by Recycling Solutions (Richmond, Indiana) and rPET2 is supplied by Polyquest Incorporated (Wilmington, NC). In both cases, the composition was measured by NMR to have an isophthalic acid (IPA) content of approximately 2 mol% (or 1.3 wt%), with the balance being EG and DMT or terephthalic acid (TPA). Additionally, the IhV measured in both cases was 0.75 (±0.02).

[0094] It should be noted that the total weight percentage (wt%) comonomer content mentioned in Table 1 and throughout this application reflects the total amount of comonomers from components intentionally added for the production of the polymer (other than EG, IPA, or DMT (or TPA)), which does not include in-situ formed by-products. When converting from known and measured mol% to wt%, the molecular weights of each monomer are used as follows: EG = 62, CHDM = 144, TMCD = 144, DMT = 194, IPA = 166, TPA = 194 (in all cases g / mol).

[0095] Table 1

[0096] Twin-screw extrusion of the blend composition: The recycled PET was blended with various amorphous copolyester resins using a co-rotating 26 mm twin-screw extruder. The extruder model used was a Coperion ZSK 26MC, 2016. This extruder has 11 different barrel zones. A general screw setting was employed. The production rate was typically about 40 - 60 pounds per hour, and all materials were fed into the extruder at the feed throat. The extruder RPM was typically 250 - 350. A Brabender type gravimetric feeder was used to meter the copolyester pellets and rPET flakes separately into the feed throat. A vacuum was pulled near the die exit to prevent material degradation. The barrel temperature was controlled at 270 - 280 °C. Prior to blending, the rPET was dried at 150 °C for 4 - 6 hours and the various copolyester resins were dried at 65 °C for 4 - 6 hours.

[0097] Injection molding of discs Miniature discs were injection molded using 300 grams of material dried in a convection oven at 170 °C for 2 hours. The material was placed in a Miniature Plastic Molding Mini-Jector Model #55-1 molding machine with a temperature profile of 277 °C at the feed throat and 288 °C at the injection nozzle. Approximately 275 grams of material was forced through the instrument and then injected into a mold that was 4 cm in diameter and 0.317 cm thick.

[0098] Measurement of haze Haze and total transmittance were measured using a BYK-Gardner Haze-Gard Plus instrument, and these values were reported as percentages (%). ASTM D1003, Standard Test Method for Haze and Luminous Transmittance of Transparent Plastics, was used.

[0099] Measurement of intrinsic viscosity (IhV) The term intrinsic viscosity (or IhV) as used herein is the viscosity of a 60 / 40 (wt / wt) phenol / tetrachloroethane solution of 0.25 grams of copolyester per 50 milliliters of solution measured at a temperature of 25 °C or 30 °C. This viscosity is a measure of the molecular weight of the polymer and is reported as dL / g. When reported herein, these values may be taken as (±0.02 dL / g).

[0100] Measurement of polymer thermal properties The melting point temperature (T m ), glass transition temperature (T g ), crystallization enthalpy (H c ), and melting enthalpy (H m ) and peak crystallization temperature (T c ) of the molded discs were determined using a TA Q2000 DSC instrument from Thermal Analyst Instruments according to ASTM D3418 at a scan rate of 20 °C / min. In a standard aluminum 40 μL sample pan purchased from TA Instruments, the sample weight was approximately 6 - 7 mg. Nitrogen was used to purge at 50 mL / min. The sample was heated from 23 °C to 285 °C (20 °C / min) in the first heating step and then cooled to -5 °C at 20 °C / min. For the second heating step, the sample was heated to 285 °C again at 20 °C / min. The reported melting point temperature (T m ) is the peak minimum of the endothermic heat flow curve of the second thermal melt scan. The reported glass transition temperature (T g ) was determined from the midpoint of the step change in enthalpy in the scan before the melting temperature.

[0101] In some cases, when reported, the molded disks were annealed prior to undergoing DSC to pre-crystallize the samples to generate a measurable melting temperature. These samples were placed in aluminum pans in an oven at 150 °C for intervals of 15 minutes, 30 minutes, 1 hour, and 2 hours. Samples were removed at each time interval to determine if crystallization had occurred (as confirmed by the sample becoming opaque and white). Once the sample had crystallized, no further annealing was performed.

[0102] Injection Molding of Thick Wall Plates To evaluate the ability to mold clear and thick parts, wedge plates of variable thickness were molded on a 200-ton TOYO injection molding machine with a 46 mm general-purpose screw. The wedge plate was a plate with variable thickness (4.5” x 4.5”) where the thickness varied linearly from 0.40” to 0.10”. The onset of crystallization-induced haze in the plate was roughly judged as the thickness at which printed matter was no longer distinguishable through the plate. The compositions were molded at processing temperatures of 249 - 266 °C and mold temperatures of 16 - 32 °C to create four different molding conditions for crystallization evaluation. The screw speed appropriate for each material was determined, but was typically 60 - 120 RPM. The cycle time was based on the output of the above process conditions, but was typically 60 - 90 s, depending on the specific composition and conditions being tested.

[0103] Reactor-Grade Polymerization Process To compare the compounded compositions of the present disclosure with reactor-grade formulations having the same general polymer composition, flask-scale syntheses were conducted to create four formulations.

[0104] Table 2 summarizes the initial charges and final compositions for the flask-scale syntheses. A 500 ml polymerization flask was connected to a nitrogen inlet, a stainless-steel stirrer, and glassware conducive to condensation polymerization. The contents were vacuum purged twice under nitrogen to inertize, and then immersed in a molten metal bath at 200 °C until the metal level was slightly above the melt level in the flask. The nitrogen flow rate was then set to 0.4 SCFH to sweep away volatiles generated during the reaction. Slow stirring was initiated until the solids were completely molten. Once molten, the stirring speed was increased to 150 - 200 rpm.

[0105] For CX1 and CX2: The flask and its contents were maintained at 200 °C for 1 hour, at 215 °C for 1 hour, and then completely immersed in a metal bath while the temperature was ramped to 265 °C over 20 minutes. Once at 265 °C, a phosphorus catalyst was added to the flask via a septum port, the nitrogen flow was stopped, and the internal pressure was reduced from atmospheric pressure to 130 torr over a 20-minute period. The temperature was then raised to 275 °C while the pressure was reduced to 15 torr over a 10-minute period and then further reduced to 3 torr over a 5-minute period, where it was held for 20 minutes. Thereafter, the pressure was reduced to 0.6 torr (for CX1) or 0.7 torr (for CX2) and held at 275 °C for 45 minutes, and then held at 278 °C for an additional 60 minutes (for CX1) or 45 minutes (for CX2).

[0106] For CX3 and CX4: The bath temperature was ramped from 200 °C to 275 °C over a 150-minute period. The phosphorus catalyst was added 5 minutes before the end of the ramp period. Thereafter, the nitrogen flow was stopped, and the internal pressure was reduced from atmospheric pressure to 0.5 torr within 20 minutes. The pressure was held at 0.5 torr and the temperature was held at 275 °C for 180 minutes (for CX3) or 165 minutes (for CX4).

[0107] As the polymer melt viscosity increased, the stirring speed was phased down from an initial speed of 150 - 200 rpm to a final speed of 50 rpm. The resulting polymer was clear and yellow in color. The polymer melt was allowed to cool for 40 minutes and then removed from the flask. Approximately 5 polymers of each composition were prepared in the manner described above and cryogenically ground and blended to pass through a 6 mm sieve, yielding approximately 1 lb of material. The final compositions and IhV values are listed in Table 2.

[0108] Table 2

[0109] Description of Results Embodiments of the present disclosure are compounded blends containing post-consumer recycled PET content. The blends were molded into thick parts without crystallization-induced haze (<20% haze on 1 / 8” injection molded plaques), and the blend compositions are compatible with PET recycling processes as defined herein. In the present disclosure, "compatible with PET recycling processes" is defined as exhibiting a melting temperature of 225 - 255 °C in the first heating DSC scan of the molded part, while also containing 15 wt% or less of diols and / or acids other than EG, TPA, or DMT (referred to herein as the total wt% of comonomer content).

[0110] Table 3 shows 17 examples (EX1 - EX17) of compounding formulations incorporating two different recycled PETs at loadings of 15 - 50 wt% in various copolyester resins. The reported IhV and thermal properties were measured on molded micro - disks. The specifically reported thermal properties were from the first - heating DSC scan and were the melting temperature (T m ), the melting enthalpy (H m ), and the glass transition temperature (T g ). In all cases, these blends surprisingly exhibited melting temperatures of 235 - 250 °C and melting enthalpies (Hm) greater than 0.20 cal / g. This means that the samples had sufficient crystallinity and the ability to crystallize fast enough during the DSC scan such that these formulations were considered acceptable for compatibility in the PET recycling process. In all cases, the resulting IhV was 0.58 - 0.70. However, it should be noted that lower and higher IhVs (in the range of 0.50 - 0.9 dL / g) of these blends would also be suitable in the present disclosure. The haze reported on 1 / 8” (3.175 mm) thick molded parts was <20% in all cases. It should be noted that the haze value of EX16 was higher than all other samples. This is because EX16 was compounded under cold conditions (260 - 270 °C), while all other materials were compounded at 270 - 280 °C and produced haze values <12%. Therefore, in some applications, the rPET / copolyester blends should be compounded at 270 - 280 °C or higher temperatures to ensure optimal visual appearance and extremely low haze. Table 3 also shows that rPETs from different sources perform well in the blends of the present disclosure.

[0111] CX5 in Table 3 is shown as a comparative example. This material was compounded with a higher CHDM polymer such that the final formulation contained a total comonomer content of 20.9 wt%. Although this sample exhibited a melting temperature, the haze was extremely high (40.2%), which was mostly attributed to the high comonomer content of the blend. Therefore, this sample indicates that the total comonomer content from diols and acids other than EG, DMT, and TPA should be ≤15%.

[0112] Table 4 contains several comparative examples. The examples in Table 4 are not compounded formulations containing rPET. The examples in Table 4 are compositions made by the previously described polycondensation method, which contain comonomer contents similar to the compounded blend compositions (CX1-CX4) in Table 3 or commercially produced PET (CX7 and CX8) or commercially produced copolyesters (CX6). This study shows that, unlike the uncompounded formulations made in reactors different from Table 4, the compounded blend compositions of the present disclosure exhibit unexpected melting temperatures and crystallization rates (EX1-EX17). The first observation is that both CX1-CX4 and CX6 exhibit melting temperatures that are completely outside the range (205-222 °C) considered to be compatible with the PET recycling process. This is in sharp contrast to the compounded blend compositions in Table 3 (melting temperatures 234-244 °C). This difference is also shown in Figure 1 . It should also be noted that the samples CX1-CX4 did not crystallize quickly enough in the DSC thermal scan to exhibit a measurable melting temperature. The melting temperature could only be measured even after annealing at 150 °C for a specified time (forcing the sample to crystallize before the DSC scan). This indicates that these reactor formulations (although having comonomer contents within the range of many samples in Table 3 but) simply crystallize too slowly and have too low a melting temperature to be considered suitable for incorporation into the PET recycling process. Therefore, the blend compositions of the present disclosure compounded with rPET (Table 3) exhibit unique properties.

[0113] Table 4

[0114] Table 3 summarizes the haze values on 1 / 8” (3.175 mm) plates. At such thicknesses, most of the haze is attributed to contamination present in the rPET material itself or to compounding at cold temperatures (poor mixing, as shown by the high haze of sample CX5). However, crystallinity can be another source of haze, especially in thick injection molded articles. In thick articles, if the part cools slowly, it allows the polymer in the core of the part time to crystallize. To successfully mold a clear thick article, the haze from crystallization must be minimized or eliminated. The compositions of the present disclosure provide a solution to this problem. Table 5 shows the results of molding several examples from Table 3 in the wedge plate test described above. All samples tested were clear up to at least 7 mm (0.28”) thickness or greater. For four samples, no crystallization haze was observed even at the thickest end of the plate. This finding is quite surprising because materials considered recyclable in the PET process typically crystallize too quickly to mold thick parts. All samples in Table 5 are considered suitable for compatibility with the PET process and also show molded thick parts in which no crystallization has occurred. It should be noted that the reported thickness values are the average of four molding conditions studied, and the reported values can be taken as ±1 mm.

[0115] Table 5

[0116] In summary, these experiments have confirmed a unique rPET / copolyester blend made by compounding, which provides molded articles containing 15 - 50% rPET, having low haze (<20% or even <10%), thick walls (4 - 25 mm) and being compatible with existing PET recycling processes - as determined by its acceptable crystallization rate and melting temperature in the range of 225 - 250 °C. The data also show that the compositions made by compounding rPET with a copolyester composition have surprising thermal properties (melting temperature, crystallization rate) compared to reactor-made products having a similar total weight % comonomer content in the range of 5 - 15%.

Claims

1. A renewable thick-walled article comprising an rPET / copolyester blend, said rPET / copolyester blend comprising: (1) 15 - 50% by weight of recycled polyethylene terephthalate (rPET) and (2) 50 - 85% by weight of at least one copolyester, which comprises: (a) A dicarboxylic acid component, which comprises: i) 70 - 100 mol% of terephthalic acid residues; ii) 0 - 30 mol% of aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) A diol component, which comprises: i) 10 - 35 mol% of 2,2,4,4 - tetramethyl - 1,3 - cyclobutanediol residues; ii) 65 - 90 mol% of ethylene glycol residues; wherein the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the diol component is 100 mol%; or said copolyester comprises: (a) A dicarboxylic acid component, which comprises: i) 70 - 100 mol% of terephthalic acid residues; ii) 0 - 30 mol% of aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) A diol component, which comprises: i) 10 to 40 mol% of 1,4 - cyclohexanedimethanol residues; ii) 60 to 90 mol% of ethylene glycol residues; wherein the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the diol component is 100 mol%; wherein said blend has a total comonomer content of 5 - 15% by weight from diols and acids other than ethylene glycol (EG), terephthalic acid (TPA) or dimethyl terephthalate (DMT); wherein the intrinsic viscosity of said copolyester as measured at 25 °C at a concentration of 0.5 g / 100 ml in 60 / 40 (wt / wt) phenol / tetrachloroethane is 0.50 - 0.9 dL / g; wherein the Tg of said copolyester is 70 - 115 °C; wherein said article has a melting temperature (Tm) of 225 - 255 °C; wherein said article has a haze value of 20% or less; and wherein said article has a thickness of 4 - 25 mm; wherein said article has a semi - crystallization time of about 3 minutes to about 20 minutes at 180 °C; wherein said article has a melting enthalpy (Hm) greater than 0.20 cal / g; wherein said article is transparent and wherein said article can be recycled in a PET recycling process.

2. The renewable thick - walled article according to claim 1, wherein said article has a semi - crystallization time of about 3 minutes to about 12 minutes at 180 °C, or about 5 minutes to about 15 minutes at 180 °C.

3. The renewable thick - walled article according to claim 1, wherein said article has a melting temperature (Tm) of 235 - 250 °C and / or has a melting enthalpy (Hm) greater than 0.20 cal / g.

4. The renewable thick-walled article according to claim 1, wherein the intrinsic viscosity of the copolyester, as measured in 60 / 40 (wt / wt) phenol / tetrachloroethane at a concentration of 0.5 g / 100 ml at 25 °C, is 0.58 - 0.70 dL / g.

5. A method for manufacturing a renewable thick-walled molded article, comprising: (A) compounding an rPET / copolyester blend, which comprises: (1) 15 - 50 wt% of recycled polyethylene terephthalate (rPET); and (2) 50 - 85 wt% of at least one copolyester, which comprises: (a) a dicarboxylic acid component, which comprises: i) 70 - 100 mol% of terephthalic acid residues; ii) 0 - 30 mol% of aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a diol component, which comprises: i) 10 - 35 mol% of 2,2,4,4-tetramethyl-1,3-cyclobutanediol residues; ii) 65 - 90 mol% of ethylene glycol residues; wherein the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the diol component is 100 mol%; or (a) a dicarboxylic acid component, which comprises: i) 70 - 100 mol% of terephthalic acid residues; ii) 0 - 30 mol% of aromatic and / or aliphatic dicarboxylic acid residues having up to 20 carbon atoms; and (b) a diol component, which comprises: i) 10 to 40 mol% of 1,4-cyclohexanedimethanol residues; ii) 60 to 90 mol% of ethylene glycol residues; wherein the total mol% of the dicarboxylic acid component is 100 mol% and the total mol% of the diol component is 100 mol%; wherein the blend has a total comonomer content of 5 - 15 wt% from diols and acids other than ethylene glycol (EG), terephthalic acid (TPA), or dimethyl terephthalate (DMT); (B) pelletizing the compounded blend; (C) drying the compounded blend at a temperature of 60 - 160 °C; (D) melting and injecting the compounded blend into a mold; and (E) ejecting the resulting molded article from the mold.

6. The method according to claim 5, wherein the blend is compounded at a temperature of 270 - 280 °C or at a temperature of 265 - 295 °C.

7. The method according to claim 5, wherein the method further optionally comprises drying rPET at a temperature of at most 150 °C and drying the copolyester at a temperature of at most 65 °C before compounding.

8. The method according to claim 5, wherein rPET and the copolyester are premixed and then the mixture is fed into an extruder for compounding.

9. The method according to claim 5, wherein rPET and the copolyester are fed separately into an extruder for compounding.

10. The method according to claim 5, wherein the molded article is transparent, or has a haze value of less than 20%, or has a haze value of less than 10%.

11. The method according to claim 5, wherein the melting temperature (Tm) of the article is 235 - 250 °C.

12. The method according to claim 5, wherein the article has a melting enthalpy (Hm) greater than 0.20 cal / g.

13. The method according to claim 5, wherein the intrinsic viscosity of the copolyester as measured at 25 °C at a concentration of 0.5 g / 100 ml in 60 / 40 (wt / wt) phenol / tetrachloroethane is 0.50 - 0.9 dL / g or 0.58 - 0.70 dL / g.

14. The method according to claim 8, wherein the article has a thickness of 4 - 25 mm.

15. The method according to claim 5, wherein the Tg of the copolyester is 70 - 115 °C.

16. The method according to claim 5, wherein the article has a semi-crystallization time of about 3 minutes to about 20 minutes.

17. The method according to claim 5, wherein the article is recyclable in a PET recycling process.

18. The renewable thick-walled article according to claim 1, wherein the article is a manufactured article selected from at least one of the following: film, sheet, container, packaging article, electrical component, cosmetic jar, bottle, medical container, personal care container, cosmetic container, molded article, lid, perfume bottle cap, tool handle, toothbrush, toothbrush handle, electronic or acoustic device housing, molded article, medical device, medical packaging, health care product, commercial food service product, tray, container, food tray, drum, storage box, bottle, food processor, blender and mixer bowl, appliance, water bottle, fry pan, washing machine component, refrigerator component, vacuum cleaner component, ophthalmic lens and frame or toy.

Images