Method for recovering polyester from an article without pre-preprocessing

Abstract

In a first aspect, the invention relates to a method for recovering polyester from an article, which comprises (i) a polyester; (ii) a part comprising a further polymer selected from polyacetal, polyvinyl chloride, and mixtures thereof.

Description

[0001] Method for recovering polyester from an article without pre-preprocessing

[0002] In a first aspect, the invention relates to a method for recovering polyester from an article, which comprises (i) a polyester; (ii) a part comprising a further polymer selected from polyacetal, polyvinyl chloride, and mixtures thereof; the method comprising: (a) providing the article and providing a solvent system comprising gamma valerolactone; (b) optionally contacting the article with the solvent system at a temperature T1 of < 170 °C, thereby obtaining a solvent system, which is enriched in dissolved further polymer of (ii), and a residue of the article, which is depleted of said further polymer and comprises the polyester; (c) contacting the article provided in (a) or the residue of the article optionally obtained in (b) with a solvent system at a temperature T2 of > 170 °C, thereby obtaining a solvent system, which is enriched in dissolved polyester compared to the solvent system provided in (a); (d) precipitating the polyester from the solvent system, which is enriched in dissolved polyester, obtained in (c), thereby obtaining a precipitated polyester and a solvent system, which is depleted in dissolved polyester. A second aspect of the invention is related to a polyester obtained or obtainable from the process of the first aspect; and a third aspect relates to the use of the polyester of the second aspect for textile applications, fiber applications, packaging applications, plastic applications, automotive applications, and / or electronic applications. A fourth aspect is directed to a method for preparing a product comprising (I) providing polyester of the first aspect; and (II) preparing a textile, a fiber, a packaging, a plastic, an automotive part, an electronic part from the polyester provided in (I). A fifth aspect relates to a method of the first aspect, focused on obtaining a separated fraction comprising the further polymer of (ii) and optionally the second polymer. A sixth aspect is directed to a method comprising the further step of converting the re-obtained polyester obtained by the process according to the first aspect to obtain a polymer product; and a seventh aspect relates to a method comprising the further step of converting a residue obtainable by or obtained by the process according to the first or the fifth aspect to obtain one or more monomer, polymer or polymer product.

[0003] State of the art

[0004] The demand for polymeric materials has drastically increased over the last decades. However, the poor biodegradability has led to large amounts of plastic waste which is in Europe usually incinerated thereby losing valuable materials and generating huge CO2 emissions. Even worse is landfill due to the poor biodegradability. Polymeric materials based on polyesters have been used extensively in the packaging sector, for example, in beverage packaging or food packaging. The vast majority of food and drink today is packaged within plastic bottles and containers, made from, for example, polyester materials comprising polyethylene terephthalate (PET). PET is also a main component of clothing nowadays. As these materials typically have poor biodegradability and are also still valuable products, it is desirable for these plastics to be recovered and recycled.

[0005] Although recycling processes have been adopted to convert the waste materials into new production materials, there are still many problems associated with recycling and recovery of polymeric materials. Waste polymeric material often includes a mixture of different polymeric materials as well as metal containing parts or non-textile parts containing still different polymers, for example, buttons, or decorative applications. Thus, in order to recycle polymeric materials, it is common to pre-process polymeric materials, i.e. to separate the different pieces, materials by sorting. However, this sorting process is labor intensive and / or requires the use of sorting machines. Even if many recycling attempts are known, it is still not possible to avoid such a preprocessing.

[0006] The technical problem underlying the present invention was thus the provision of a method for recovery of a polyester from a polymeric material, which overcomes these disadvantages, and which especially enables obtaining polyester from materials, which contain metal parts and / or non-textile parts, without a pre-processing, while obtaining the polyester material undamaged.

[0007] In a first aspect the invention relates to a method for recovering polyester from an article, which comprises

[0008] (i) a polyester;

[0009] (ii) a metal containing part and / or a part comprising a further polymer selected from polyacetal, polyvinyl chloride, and mixtures thereof; the method comprising:

[0010] (a) providing the article and providing a solvent system;

[0011] (b) optionally contacting the article with the solvent system at a temperature T1 of < 170 °C, thereby obtaining a solvent system, which is enriched in dissolved further polymer of (ii), and a residue of the article, which is depleted of said further polymer and comprises the polyester and optionally the metal containing part of (ii);

[0012] (c) contacting the article provided in (a) or the residue of the article optionally_obtained in (b) with a solvent system at a temperature T2 of > 170 °C, thereby obtaining a solvent system, which is enriched in dissolved polyester compared to the solvent system provided in (a), and optionally a residue of the article, which is depleted of polyester and comprises the metal containing part of (ii);

[0013] (d) precipitating the polyester from the solvent system, which is enriched in dissolved polyester, obtained in (c), thereby obtaining a precipitated polyester and a solvent system, which is depleted in dissolved polyester. It was surprisingly found that the inventive method allows to obtain polyester from an article comprising metal containing parts and / or non-textile parts, without any pre-processing needed, especially without any separation by sorting. Furthermore, the polyester as well as polymers from non-textile parts could be re-obtained in undamaged form with Mw values, which were at least equal to the Mw values of the starting materials.

[0014] The “part comprising a further polymer” of (ii) may besides polyacetal and / or polyvinyl chloride also contain polyester parts. This polyester, if present, is preferably the same polyester as the polyester of (a). In these cases, if such polyester is present, the precipitated polyester obtained in (d) comprises the polyester of (a) and the polyester of part comprising a further polymer.

[0015] “Contacting” in optional step (b) and in step (c) preferably means that the article provided in (a) or the residue of the article optionally obtained in (b) is at least partially immersed in the solvent system. Preferably, article provided in (a) or the residue of the article optionally obtained in (b) is at least partially immersed in the solvent system in that at least 60 %, more preferably at least 70 %, more preferably at least 80 %, more preferably at least 90 %, more preferably at least 95 %, more preferably at least 99 % of the surface of the article provided in (a) or of the residue of the article optionally obtained in (b) are in contact with the solvent system, based on the total surface of the f the article provided in (a) or of the residue of the article optionally obtained in (b) being 100%.

[0016] Regarding optional step (b), “enriched in further polymer” means that at least 50 weight-%, preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, more preferably at least 95 weight-%, of the further polymer -if present- comprised in the article provided in (a), are dissolved in the solvent system, based on 100 weight-% of further polymer - if present - comprised in the article provided in (a). “Depleted of said further polymer” regarding the residue (optionally) obtained in (b) means that < 50 weight-%, preferably < 40 weight-%, more preferably < 30 weight-%, more preferably < 20 weight-%, more preferably < 10 weight-%, more preferably < 5 weight-%, of the further polymer - if present - comprised in the article provided in (a), are still present in the residue, based on 100 weight-% of the further polymer- if present - comprised in the article provided in (a).

[0017] Regarding step (c), “solvent system, which is enriched in dissolved polyester compared to the solvent system provided in (a)” means that at least 50 weight-%, preferably at least 60 weight- %, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, more preferably at least 95 weight-%, of the polyester comprised in the article provided in (a), are dissolved in the solvent system, based on 100 weight-% of the polyester comprised in the article provided in (a). Regarding the optionally obtained residue of the polymer blend of step (c), “depleted of polyester and comprises optionally the metal containing part of (ii)” means that < 50 weight-%, preferably < 40 weight-%, more preferably < 30 weight-%, more preferably < 20 weight-%, more preferably < 10 weight-%, more preferably < 5 weight-%, of the polyester comprised in the material provided in (a), are still present in the residue, based on 100 weight-% of the polyester comprised in the article provided in (a), wherein still at least 50 weight-%, preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, more preferably at least 95 weight-%, of the metal part -if present- comprised in the article provided in (a), are present in the residue, based on 100 weight-% of the metal part - if present - comprised in the article provided in (a).

[0018] Regarding step (d), “solvent system, which is depleted in dissolved polyester” means that compared to 100 weight-% of polyester comprised in the solvent system obtained in (c), at least 50 weight-%, preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, are precipitated and no longer dissolved in the solvent system.

[0019] Metal containing parts and / or a parts comprising a further polymer

[0020] In some embodiments of the method, the metal containing part and / or part comprising a further polymer is / are closing and / or decoration means, more preferably selected from the group consisting of zipper, ribbon, cramp, button, sequin, patch, hook, eyelet, grommet, buckle, clasp and mixtures of two or more thereof, preferably from the group consisting of zipper, button, sequin and mixtures of two or more thereof.

[0021] In some embodiments of the method, the metal of the metal part is selected from the group consisting of brass, silver, nickel silver, aluminum, gold, old brass, nickel and mixtures of two or more thereof.

[0022] Preferably, the article comprises

[0023] (i) a polyester;

[0024] (ii) a part comprising a further polymer selected from polyacetal, polyvinyl chloride, and mixtures thereof, which preferably at least comprises polyvinyl chloride. Preferably, the part comprising a further polymer is / are closing and / or decoration means, more preferably selected from the group consisting of zipper, ribbon, cramp, button, sequin, patch, hook, eyelet, grommet, buckle, clasp and mixtures of two or more thereof, preferably from the group consisting of zipper, button, sequin and mixtures of two or more thereof. Preferably, the further polymer comprises or is polyvinyl chloride (PVC) and the closing and / or decoration means, preferably selected from the group consisting of zipper, ribbon, cramp, button, sequin, patch, hook, eyelet, grommet, buckle, clasp and mixtures of two or more thereof comprise or consist of PVC.

[0025] Especially for parts comprising a further polymer, which comprise or consists of PVC, the method is advantageous as it allows to dissolve the PVC from the article at low temperatures below 170°C, which in turn avoids that hydrochloric acid (HCI) is set free from PVC, which can happen at higher temperatures (see Dietrich Braun, Manfred Thallmaier, Journal of Polymer Science: Polymer Symposia, 16, 4, 1967, 2351-2364). Avoidance of HCI is favorable as HCI causes decomposition of the polyester. Furthermore, the method allows separating PVC quantitatively from the polyester, Dissolving PVC first in step (b) and maintaining the polyester in nondissolved form until step (c) is conducted offers also the advantage that entraining of parts of PVC when precipitation polyester can be reduced or even avoided, which could not be avoided if the PVC would be dissolved together with polyesterin step (c).

[0026] In some embodiments of the method, the polyacetal of the part comprising a further polymer is selected from the group consisting of polyoxymethylene homopolymer, polyoxymethylene copolymer and mixtures of polyoxymethylene homopolymer and polyoxymethylene copolymer, wherein polyoxymethylene copolymer is preferably polyoxymethylene, wherein in the range of from 0.1 to 1.5 % of the -CH2O- groups are replaced by -CH2CH2O- groups.

[0027] In some embodiments of the method, neither between (a) and (b) nor between (b) and (c), nor - in the absence of (b)- between (a) and (c) a separation of metal containing part and / or part comprising a further polymer from the polyester (i) of the article is done (no pre-processing).

[0028] In some embodiments of the method, neither between (a) and (b) nor -in the absence of (b)- between (a) and (c), a mechanical pre-treatment, more preferably a shredding, is done.

[0029] Second polymer / third polymer / colorant / filler

[0030] In some embodiments of the method, the article further comprises

[0031] (iii) one or more component(s) selected from the group consisting of a second polymer, a third polymer, a colorant and a filler, wherein second polymer and third polymer are different from each other and different from the polyester of (i) and from the further polymer of the parts comprising a further polymer of (ii).

[0032] In some embodiments of the method, second polymer and / or colorant, if present, is / are dissolved in optional step (b) so that the obtained solvent system, which is enriched in dissolved further polymer of the parts comprising a further polymer of (ii) is also enriched in second polymer and / or in colorant, and the residue of the article obtained in (b), which is depleted of said further polymer and comprises the polyester and optionally the metal containing part of the closing and / or decoration means (ii) is also depleted of the second polymer and / or the colorant.

[0033] In some embodiments of the method, the third polymer, if present, is not dissolved in optional step (b) and not dissolved in step (c), so that the residue of the article obtained in (b), which is depleted of further polymer and comprises the polyester and optionally the metal containing part of (ii) also comprises the third polymer; and preferably the residue of the article obtained in (c), which is depleted of polyester and comprises the metal containing parts of (ii) also comprises the third polymer.

[0034] In some embodiments of the method, the filler if present, is optionally partially or completely dissolved in optional step (b) and / or optionally partially or completely dissolved in step (c), so that the residue of the article obtained in (b), which is depleted of further polymer and comprises the polyester and optionally the metal containing part of (ii) also optionally comprises the filler or a part of the filler; and preferably the residue of the article obtained in (c), which is depleted of polyester and which optionally comprises the metal containing parts of (ii), optionally also comprises the filler or a part of the filler.

[0035] The expressions “(optionally) partially or completely dissolved” regarding the filler for step (b) and / or (c) and “(optionally) comprising the filler or a part of the filler” regarding the residue obtained in (b) and / or the residue obtained in (c) mean that, if a filler is present in the polymer blend provided in (a), which is soluble in a solvent system at a temperature T1 , said soluble filler is also dissolved in the solvent, which is enriched in dissolved further polymer of (ii) in (b). In case that not (only) a filler soluble at T1 is present in the article provided in (a) but (also) a filler, which is not soluble in a solvent system at a temperature T2, said insoluble filler remains in the residue of the article, which is depleted of polyester and comprises the metal containing part of (ii) obtained in (c). In cases where the article provided in (a) comprises only filler(s) soluble in in a solvent system at a temperature T1 , no filler remains in the residue obtained in (b) and, consequently, in the residue obtained in (c). In cases where only filler(s) insoluble in in a solvent system at a temperature T2 are contained in the particle provided in (a), all filler(s) remain(s) in the residue of the article obtained in (b) and also in the residue obtained in (c). Regarding “depleted” and “enriched” in the context of second polymer, third polymer, and filler, the same applies as outlined above in detail. Regarding colorant, “enriched in colorant” with respect to optional step (b) means that at least 50 weight-%, preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight- %, more preferably at least 95 weight-%, of the colorant - if present comprised in the polyester of the material provided in (a) are dissolved in the solvent system, based on 100 weight-% of the colorant - if present - comprised in the polyester comprised in the material provided in (a). “Depleted of said colorant” regarding the residue (optionally) obtained in (b) means that < 50 weight-%, preferably < 40 weight-%, more preferably < 30 weight-%, more preferably < 20 weight-%, more preferably < 10 weight-%, more preferably < 5 weight-%, of the colorant - if present - comprised in the polyester comprised in the material provided in (a), are still present in the residue, based on 100 weight-% of the colorant - if present - comprised in the polyester comprised in the material provided in (a). This means that colorant, which is comprised in the polyester (i), is comparatively easy removed in step (c), i.e. is dissolved together with the polyester in the solvent system in step (c), whereas colorant being comprised in third polymer - if present- is not easily dissolved but rather remains to a large extend in the third polymer and thus also in the residue comprising said third polymer.

[0036] In some embodiments of the method, the article is a textile article, preferably a baggage or a clothing or a part of a baggage or a clothing, a clothing preferably being selected from the group consisting of swim wear, shirt, trousers, pullover, blouse, under wear, sock, jacket, skirt, top, sweater, short, overall, coverall, jumpsuit, romper, suits, pajama, lingerie, coat, glove, and vest; a baggage preferably being selected from the group consisting of hip bag, backpack, bag, pouche, and suitcase.

[0037] In some embodiments of the method, the article is selected from the group consisting of a toying article, a sport equipment article, an outdoor equipment article or combined articles thereof. A toying article is, for example, a ball or an air mattress. An outdoor equipment article is, for example, a camping stool, and a sport equipment article is, for example, a paddle.

[0038] Intermediate steps

[0039] In some embodiments, the method comprises, if (b) is conducted, after (b) and before (c) (u) separating solvent system, which is enriched in dissolved further polymer of (ii), and the residue of the article, which is depleted of said further polymer and comprises the polyester provided in (a), thereby obtaining a separated solvent being enriched in further polymer and a separated residue of the article, which is depleted of said further polymer and comprises the polyester. Separation in (u) is preferably done by methods and means known to the skilled person, especially solid-liquid separation methods such as filtration, for example, heated pressure filtration, sedimentation or centrifugation (see Handbuch der mechanischen Fest-Flussig-Tren- nung Taschenbuch - 29. April 2004 von Klaus Luckert (Herausgeber)).

[0040] In some embodiments, the method comprises, if (b) is conducted, after (b) and before (c):

[0041] (v) washing the residue of the article obtained in (b) with a washing solvent, thereby obtaining a washed residue, which is depleted of said further polymer and comprises the polyester and optionally the metal containing part of (ii) provided in (a);

[0042] (w) optionally drying the washed residue obtained in (v).

[0043] In some embodiments, the method comprises, if (b) is conducted, after (b), preferably after (u), and before (c):

[0044] (v) washing the (separated) residue of the article obtained in (b) or in (u), with a washing solvent, thereby obtaining a washed residue, which is depleted of said further polymer and comprises the polyester provided in (a);

[0045] (w) optionally drying the washed residue obtained in (v).

[0046] Washing in optional step (v) is preferably done with a solvent system having features (s.1 ), (s.2) and (s.3) as defined herein, preferably with a solvent system comprising one or more of the solvents) of any one of the groups defined herein. Preferably, washing in optional step (v) is done with the same solvent system as used for (b). In some embodiments, washing is done with a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, acetonitrile, ethyl acetate, acetone, water or a mixture of two or more of these solvents. In some embodiments, the washing in optional step (v) is done with a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, acetonitrile, ethyl acetate, acetone, water, GVL, or a mixture of two or more of these solvents. Drying in optional step (w) is preferably done under one or more conditions selected from the group consisting of a pressure in the range of from 1 to 1013 mbar; a temperature in the range of from 50 to 210 °C, preferably in the range of from 60 to 180°C, more preferably in the range of from 80 to 160 °C; drying time in the range of from 30 minutes to 24 hours; drying in an atmosphere comprising nitrogen, preferably in an atmosphere having at least 90 volume-%, more preferably 95 volume-%, more preferably at least 98 volume-% nitrogen. Drying is done by one or more methods selected from the group consisting of contact drying, convection drying and radiation drying. Contacting in step (c) is then done based on the washed (and optionally dried) residue obtained in (b). In some embodiments, the method comprises after (c), if a residue is present, and before step (d)

[0047] (x.1) separating the solvent system, which is enriched in dissolved polyester and comprises optionally the filler or a part of the filler obtained in (c), from the residue of the polymer blend, wherein the separation is preferably done by heated filtration, more preferably by heated filtration at a temperature T3 in the range of from T2 minus 20 °C to T2 plus 20 °C (T3 = T2 ± 20°C), more preferably at a temperature T3 in the range of from T2 minus 10 °C to T2 plus 10 °C (T3 = T2 ± 10°C), thereby obtaining the solvent system, which is enriched in dissolved polyester and comprises optionally the filler or a part of the filler, and a separated residue;

[0048] (x.2) optionally contacting said separated residue of the polymer blend obtained in (x.1) with solvent system, preferably at a temperature T3 as defined above in (x.1), followed by filtration, preferably heated filtration at a temperature T3 as defined above in (x.1), thereby obtaining a residue of the polymer blend, which is further depleted of polyester and comprises one or more of the third polymer, the filler or a part of the filler; and a solvent system, which contains further amount of the polyester and comprises optionally the filler or a part of the filler;

[0049] (x.3) optionally combining the solvent system, which contains the further amount of the polyester and comprises optionally the filler or a part of the filler obtained in (x.2) with the solvent system, which is enriched in dissolved polyester and comprises optionally the filler or a part of the filler, separated in (x.1); wherein precipitation in (d) is done based on the separated solvent system obtained in (x.1) or based on the combined solvent system obtained in (x.3).

[0050] In heated filtration, the solution, filter, and funnel are heated, preferably heated so that each has temperature T3. Other means and methods for the separation in (x.1) are known to the skilled person such as non-heated filtration. In some embodiments, it is preferred that the heated filtration is done under a pressure of >1 bar, more preferably at a pressure in the range of from 1 bar to 30 bar, preferably in the range of from 1 to 10 bar, more preferably in the range of from 1 to 6 bar (heated pressure filtration). Preferably, the filter used in heated filtration is stable, especially does not dissolve or degrade, at the respective conditions and in connection with the respective solvent system. For example, the filter may be made of polyetheretherketone.

[0051] Preferably, the contacting in (x.2) is done in that, especially in cases where heated filtration is used in (x.1), the residue of the polymer blend obtained in (x.1) remains on the filter and is there brought into contact with solvent system, wherein the solvent system, which contains the remaining amount of the polyester and comprises optionally the filler or a part of the filler obtained in (x.2), is separated thereof due to filtration. In some embodiments, the solvent system, which contains the remaining amount of the polyester and comprises optionally the filler or a part of the filler obtained in (x.2) is combined with the solvent system, which is enriched in dissolved polyester and comprises optionally the filler or a part of the filler, obtained in (x.1).

[0052] In some embodiments, the method comprises after (d)

[0053] (y.1) separating the precipitated polyester obtained in (d) from the solvent system, which is depleted in dissolved polyester and comprises optionally the filler or a part of the filler, thereby obtaining a precipitated polyester and the solvent system, which is depleted in dissolved polyester and which optionally comprises the filler or a part of the filler;

[0054] (y.2) optionally washing the precipitated polyester obtained in (y.1);

[0055] (y.3) drying the precipitated polyester obtained in (y.1) or the washed precipitated polyester obtained in (y.2), thereby obtaining a dried (washed) precipitated polyester.

[0056] The separation in (y.1) is done by methods and means known to the skilled person, especially solid-liquid separation methods such as filtration, for example, heated pressure filtration, sedimentation or centrifugation (see Handbuch der mechanischen Fest-Flussig-Trennung Taschen- buch - 29. April 2004 von Klaus Luckert (Herausgeber)). Washing in optional step (y.1) is preferably done with a solvent system having features (s.1 ), (s.2) and (s.3) as defined herein, preferably with a solvent system comprising one or more of the solvent(s) of any one of the groups defined herein. In some embodiments, a subsequent washing of the washed residue is done with a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, acetonitrile, ethyl acetate, acetone, water or a mixture of two or more of these solvents or with a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, acetonitrile, ethyl acetate, acetone, water, GVL, or a mixture of two or more of these solvents. In some embodiments, washing in optional step (y.2) is preferably done with a solvent system having features (s.1 ), (s.2) and (s.3) as defined herein, preferably with a solvent system comprising one or more of the solvent(s) of any one of the groups defined herein. In some embodiments, a subsequent washing of the washed residue is done with a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, acetonitrile, ethyl acetate, acetone, water or a mixture of two or more of these solvents or with a solvent selected from the group consisting of methanol, ethanol, propanol, isopropanol, acetonitrile, ethyl acetate, acetone, water, GVL, or a mixture of two or more of these solvents. Drying in step (y.3) is preferably done under one or more conditions selected from the group consisting of a pressure in the range of from 1 to 1013 mbar; a temperature in the range of from 50 to 210 °C, preferably in the range of from 60 to 180°C, more preferably in the range of from 80 to 160 °C; drying time in the range of from 30 minutes to 24 hours; drying in an atmosphere comprising nitrogen, preferably in an atmosphere having at least 90 volume-%, more preferably 95 volume-%, more preferably at least 98 vol- ume-% nitrogen. Drying is done by one or more methods selected from the group consisting of contact drying, convection drying and radiation drying.

[0057] In some embodiments, the method comprises

[0058] (y.4) pelletizing the dried (washed) precipitated polyester obtained in (y.3), thereby obtaining a pelletized polyester.

[0059] “Pelletizing” is the process of compressing or molding a material into the shape of a pellet. Pelletizing can be done as known in the art, for example, by extruding and subsequently pelletizing under water or by strand granulation.

[0060] In some embodiments, the method comprises after (d) or after (y.3) or after (y.4), preferably after (y.3) or after (y.4)

[0061] (z) increasing the intrinsic viscosity of the precipitated polyester obtained in (d) or of the dried (washed) precipitated polyester obtained in (y.3) or of the pelletized polyester obtained in (y.4).

[0062] Increasing the intrinsic viscosity according to (z) is done in solid state and / or wherein at least a part of the precipitated polyester is in molten state, wherein increasing the intrinsic viscosity enables to increase molecular weight of the polyester.

[0063] Increasing the intrinsic viscosity is preferably done at a temperature in the range of from 200 to 230 °C, more preferably in the range of from 200 to 220 °C; and / or, preferably and, for a period of time in the range of from 1 to 80 hour(s), preferably 10 to 50 hours; and / or, preferably and, at a pressure in the range of from 5 to 1013 mbar.

[0064] Precipitation in (d) - cooling

[0065] In some embodiments of the method, precipitation in (d) comprises cooling the solvent system obtained in (c), which is enriched in dissolved polyester compared to the solvent system provided in (a), from T2 to a temperature below 140°C, wherein the cooling is done so that the temperature of the solvent system, which is enriched in dissolved polyester, is within the temperature range of from 160 to 145 °C for a period of time of at least 5 minutes, preferably at least 10 minutes, more preferably in the range from 5 to 120 minutes, more preferably in the range of from 10 to 100 minutes, more preferably in the range of from 15 to 100 minutes. In some embodiments of the method, cooling in (d) is done so that the solvent system, which is enriched in dissolved polyester, has within the temperature range of from 160 to 145 °C a viscosity in the range of from 1 to 12 Pa s, more preferably in the range of from 1 to 10 Pa s, determined according to DIN EN ISO 2555 (2018-09).

[0066] In some embodiments of the method, cooling is done with a cooling rate of < 3.0 °C / min, more preferably < 1.5 °C / min, more preferably in the range of from 0.05 to 3.0 C / min, more preferably in the range of from 0.13 to 3.0 °C / min, more preferably in the range of from 0.15 to 1.5 °C / min, more preferably in the range of from 0.15 to 1.0 °C / min.

[0067] In some embodiments of the method, cooling of the solvent system in (d) is done from T2 to a temperature below 100°C.

[0068] In some embodiments of the method, the cooling of the solvent system in (d) is done from T2 to a temperature below 100°C with a cooling rate of < 3.0 °C / min, preferably < 1.5 °C / min, more preferably in the range of from 0.05 to 3.0 °C / min, more preferably in the range of from 0.13 to 3.0 °C / min, more preferably in the range of from 0.15 to 1.5 °C / min, more preferably in the range of from 0.15 to 1.0 °C / min.

[0069] In some embodiments of the method, the cooling of the solvent system in (d) is done without addition of an anti-solvent. An “antisolvent” is a solvent having a solubility regarding the polyester < 1 g / kg at a temperature in the range of from 20 to 25 °C. In some embodiments, only a small amount of one or more antisolvent(s) is / are added to and / or is / are present in the solvent system in step (d), wherein a small amount means that less than 5 weight-%, preferably less than 4 weight-%, more preferably less than 3 weight-%, more preferably less than 2 weight-%, more preferably less than 1 weight-% of antisolvent(s) is / are added and / or is / are present based on the total weight of the solvent system including the antisolvent(s) being 100 weight-%.

[0070] Solvent system

[0071] In some embodiments of the method, the solvent system comprises one or more solvent(s), wherein

[0072] (s.1) the solvent system has Hansen solubility parameters with respect to energy from dispersion forces between molecules (5DSS), energy from dipolar intermolecular force between molecules (5PSS) and energy from hydrogen bonds between molecules (5HSS), which fullfill equitation 1

[0073] (8.8)2> 4(6Dss-20)2+ (5PSS-11.8)2+ (5Hss-4.5)2 [equitation 1];

[0074] (s.2) each solvent of the solvent system has a boiling point at 1013 hPa of at least 160 °C; and (s.3) solvents having a functional group selected from the group consisting of hydroxyl (OH), amino (NH2), carboxyl (COOH), and thiol (SH) are excluded.

[0075] The boiling point of a solvent is understood as the boiling point of the solvent at the respective pressure. Any solvent system for which 4(5Dss-20)2+ (5PSS-11.8)2+ (5Hss-4.5)2is larger than (8.8)2(i.e. 77.44) is not suited to dissolve polyalkylene terephthalate based polymer properly and any solvent system for which 4(5Dss-20)2+ (5PSS-11.8)2+ (5Hss-4.5)2is equal to or smaller than (8.8)2(i.e. 77.44) is suitable for dissolving polyalkylene terephthalate based polymer. In case of two or more solvents being part of the solvent system, i.e. n solvents with n being an integer with n>2 and i=1 ... n, the Hansen solubility parameters of the resulting mixture with respect to each of 5DSS, 5HSSand 5PSSare calculated, knowing the percentage part of each solvent in the solvent system, as the weighted arithmetic mean from 5DSj, 5HSiand 5PSj Of each of the n solvents S(i). The Hansen parameters of solvents are to be found in in BIOVIA COSMOquick 2022.

[0076] Considering the three-dimensional form given by equitation 1 in the three-dimensional Hansen space, a sphere is formed which has its center at 5DC= 20, 5PC= 11.8 and 5HC= 4.5 and a radius r of 8.8. The doubling of the dispersion parameter value is required, according to Charles Hansen, for achieving a spherical form. A Hansen sphere, since there are no negative values possible for 5H, can also be considered as a dome, i.e. a half-sphere. PET has Hansen parameters according to the 5thEdition 5.1.03 (2008) of the HANSEN Solubility Parameters in Practice (HSPiP) of 5D = 18.2, 5P = 6.4 and 5H = 6.6 and lies within the sphere but not at its center.

[0077] In some embodiments of the method, at least 90 weight-%, more preferably at least 95 weight- %, more preferably at least 98 weight-%, more preferably at least 99 weight-%, of the solvent system consist of one solvent system, which fulfills equitation 1 , wherein in cases where the solvent system consists of only one solvent system, the temperature T is a temperature at least 7K below the boiling temperature of said one solvent.

[0078] In some embodiments of the method, at least 90 weight-%, more preferably at least 95 weight- %, more preferably at least 98 weight-%, more preferably at least 99 weight-%, of the solvent system consist of two or more solvent(s), wherein the respective mixture fulfill(s) equitation 1.

[0079] In some embodiments of the method, the one or more solvent(s) is / are selected from the group consisting of N,N-dimethylbenzamide, N,N-dimethylphenylacetamide, 1 ,4-benzoquinone, acetophenone, dimethyl terephthalate, 1 ,3,5-trimethoxybenzene, 2-phenylacetophenone, N- methylcaprolactam, methylbenzoate, methyl-4-methoxybenzoate, butylene carbonate, N- ethylpyrrolidone, benzophenone, di-benzyl malonate, N-ethyl-caprolactam, methyl 2-(5-oxotet- rahydrofuran-3-yl)acetate (FAME), methyl 2-(5-oxotetrahydrofuran-2-yl)acetate, propiophenone, N-methoxypropyl-pyrrolidone, 1 ,4-cyclohexanedione, cyclohexane-carbonate, N-methoxyethyl- pyrrolidone, N,N-diethylphenylacetamide, phenyl acetate, 1-(2-hydroxyethyl)pyrrolidin-2-one acetate (HEPAc), N,N-diethylbenzamide, isopropyl-benzoate, cyclohexyl phenyl ketone, phenylacetic acid ethylester, phenylacetat.N-methyl-morpholine, benzyl-propionate, benzylacetate, Ne- opentyl-glycol-dibenzoate, tetrahydrofurfuryl acetate, N-methyl-imidazole, benzyl butyrate, 2- pyrrolidone, 2-phenoxyethanol propionate, 2-phenoxyethyl isobutyrate, N,N-dipropylbenzamide, N,N-dimethylacetamide, N,N-diethylacetamide, dihydrolevoglucosenon (Cyrene), propylenecarbonate, caprolactone, dimethylisosorbide, N-butylpyrrolidone, t-butylpyrrolidone, methyl-1-me- thyl-5-oxopyrrolidine-3-carboxylate (MMOC), gamma-valerolactone (GVL), delta-valerolactone, gamma butyrolactone, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv Polar- clean), caprolactam, phen ethyl acetate, methyl phenylacetate, benzyl benzoate, N,N-dimethyl- lactamide (Agnique AMD 3L), 1 ,3-dimethyl-2-imidazolidinone (DMI), and dimethyl sulfoxide (DMSO). In some embodiments of the method, the one or more solvent(s) is / are selected from the group consisting of dihydrolevoglucosenon (Cyrene), propylenecarbonate, caprolactone, dimethylisosorbide, N-butylpyrrolidone, t-butylpyrrolidone, methyl-1-methyl-5-oxopyrrolidine-3-car- boxylate (MMOC), gamma-valerolactone (GVL), Delta-valerolactone, gamma butyrolactone, dimethylsulfoxide, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (RhodiasolvOPolarclean), caprolactam, phen ethyl acetate, methyl phenylacetate, benzyl benzoate, phenyl benzoate, methyl benzoate, propyl benzoate, and dimethyl sulfoxide (DMSO). In some embodiments of the method, the one or more solvent(s) of the solvent system is / are selected from the group consisting of propylenecarbonate, N-butylpyrrolidone, t-butylpyrrolidone, methyl-1-methyl-5-oxopyrroli- dine-3-carboxylate (MMOC), Delta-valerolactone, gamma butyrolactone, methyl 5-(dimethyla- mino)-2-methyl-5-oxopentanoate (RhodiasolvOPolarclean), caprolactam, phenethyl acetate, methyl phenylacetate, benzyl benzoate, phenyl benzoate, methyl benzoate, propyl benzoate and GVL. In some embodiments of the method, the one or more solvent(s) is / are selected from the group consisting of propylenecarbonate, N-butylpyrrolidone, t-butylpyrrolidone, methyl-1- methyl-5-oxopyrrolidine-3-carboxylate (MMOC), Delta-valerolactone, gamma butyrolactone, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (RhodiasolvOPolarclean), caprolactam, phen ethyl acetate, methyl phenylacetate, benzyl benzoate, phenyl benzoate, methyl benzoate, and propyl benzoate. In some embodiments of the method, the one or more solvent(s) of the solvent system is / are selected from the group consisting of propylenecarbonate, N-butylpyrrolidone, t- butylpyrrolidone, methyl-1-methyl-5-oxopyrrolidine-3-carboxylate (MMOC), methyl 5-(dimethyla- mino)-2-methyl-5-oxopentanoate (RhodiasolvOPolarclean), phenethyl acetate, and GVL. In some embodiments of the method, the one or more solvent(s) is / are selected from the group consisting of propylenecarbonate, N-butylpyrrolidone, t-butylpyrrolidone, methyl- 1-methyl-5-ox- opyrrolidine-3-carboxylate (MMOC), methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (Rho- diasolvOPolarclean), and phen ethyl acetate.

[0080] In some embodiments of the method, ethyl benzoate and butyl benzoate are excluded as solvents).

[0081] In some embodiments of the method,

[0082] (s.3a) solvents having a functional group selected from the group consisting of hydroxyl (OH), amino (NH2), secondary amine (-NH-), carboxyl (COOH), and thiol (SH) are excluded.

[0083] In some embodiments of the method, the solvent system comprises gamma-valerolactone, wherein more preferably at least 50 weight-%, more preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 99 weight-% of the solvent system consists of gamma-valerolactone, based on the total weight of the solvent system being 100 weight-%.

[0084] In some embodiments of the method, in optional step (b) the same solvent system as in (c) is used.

[0085] Polyester

[0086] In some embodiments of the method, the polyester is based on 1,4-butanediol or 1,2-ethandiol, more preferably the polyester according to (i) is selected from the group consisting of a polymer based on 1,4-butanediol and terephthalic acid (polybutylene terephthalate, PBT), a polymer based on 1,2-ethanediol and terephthalic acid (polyethylene terephthalate, PET), a copolymer of 1 ,4-butanediol, adipic acid and terephthalic acid (polybutylenadipat-terephthalat, PBAT), a polymer of 1,2-ethanediol and 2,5-furandicarboxylic acid (polyethylene furanoate, PEF) and mixtures of two or more of these (co)polymers, more preferably, the polyester comprises at least PET and / or PBT, more preferably the polyester is PET or PBT or a mixture of PET and PBT. More preferably the polyalkylene terephthalate based polymer comprises or is PET.

[0087] Colorant In some embodiments of the method, the colorant is selected from the group consisting of dye and optical brightener and mixtures of dye and optical brightener.

[0088] A “colorant” is a substance that cause the change of color impression of material. This comprises dyes, which absorb wavelength intervals of visible light (400 to 780 nm) and optical brighteners, which amplify the light emission of a material through UV light adsorption and emittance of visible light (through fluorescence), i.e. an optical brightener converts radiation that is not visible to the human eye (<400nm) into visible fluorescence radiation of the blue-red spectral range (400 to 600 nm). Colorants usable or used for changing the color impression of polymeric materials are known to the skilled person. In the context of the present invention, the term “dye” means any kind of dye such as dye, pigment, dispersion, wherein a dye is, for example, one or more selected from the group consisting of acid dye, basic dye, direct dye, disperse dye, azoic dye, food dye, solvent dye, organic dye, organic pigment, sulfur dye, mordant dye and vat dye. The term “optical brightener” comprises optical brightening agents, fluorescent brightening agents, and fluorescent whitening agents.

[0089] Overviews of colorants for polymeric materials can be found, for example, in “Dyes and Pigments” Metin Agikyildiz, Kubra Gunes, Ahmet Gurses Springer, 2016 (ISBN: 10 : 3319338900); Industrial Organic Pigments - Klaus Hunger, Thomas Heber, Martin II. Schmidt, Friedrich Reisinger, Stefan Wanne Wiley-VCH, 4thedition, 2018 (ISBN: 978-3-527-32608-2); Chemistry and Technology of Natural and Synthetic Dyes and Pigments - Ashis Kumar Samanta, Nasser Awwad, IntechOpen, 2020 (ISBN: 9781789859980, 9781789859973, 9781839687587); Encyclopedia of Color, Dyes, Pigments - Volume 1, Gerhard Pfaff, de Gruyter, 2021 (ISBN: 311058588X); Heinrich Zollinger: Color Chemistry: Syntheses, Properties, and Applications of Organic Dyes and Pigments. 3rdedition. WILEY-VCH Verlag, Weinheim 2003 (ISBN: 3-906390- 23-3); Klaus Hunger (Ed.): Industrial Dyes: Chemistry, Properties, Applications. WILEY-VCH Verlag, Weinheim 2003 (ISBN: 3-662-01950-7); Hermann Rath: Lehrbuch der Textilchemie. ein- schl. der textilchemischen Technologie. 2nd edition. Springer-Verlag, Berlin, Heidelberg 1963 (ISBN: 978-3-662-00065-6); Wilfried Kratzert, Rasmus Peichert: Farbstoffe. Quelle & Meyer, Heidelberg 1981 (ISBN: 3-494-01021-8); Ullmann’s Encyclopedia of industrial chemistry, Wiley- VCH, 2000, sections “dyes and pigments” and “dyes, general survey” (ISBN: 9783527303854).

[0090] Preferably, in step b) only colorant(s) is / are removed from the polymer blend and transferred into the solvent system, which is / are non-covalently bonded to the polyester.

[0091] Second polymer In some embodiments of the method, the second polymer is selected from the group consisting of polyurethane (Pll), polyethylene glycol (PEG), polytetrahydrofuran (pTHF), mixtures of these polymers and copolymers of these polymers, wherein the second polymer is more preferably Pll or a copolymer of Pll and PEG and / or pTHF, more preferably spandex. “Spandex” is preferably a copolymer of polyurethane and polyethylene glycol and / or polytetrahydrofurane, more preferably Spandex is a copolymer of polyurethane and polyethylene glycol or a copolymer of polyurethane with polytetrahydrofurane.

[0092] Third polymer

[0093] In some embodiments of the method, the third polymer is selected from polypropylene (PP), polyethylene (PE), polyamide (PA), natural polymer (such as cotton, viscose, linen) and mixtures of two or more thereof. PA comprises preferably PA6 and PA66; however, in some embodiments PA6 is excluded as third polymer, i.e. the third polymer when being PA is PA66.

[0094] Filler

[0095] In some embodiments of the method, the filler is selected from the group consisting of glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, disodium carbonate), adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent.

[0096] In some embodiments of the method, wherein the polyester comprises, preferably is PBT and the filler is one or more selected from the group consisting of glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, disodium carbonate), adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent, preferably the filler is one or more selected from glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, Na2CO3).

[0097] In some embodiments of the method, wherein the polyester comprises, preferably is PET and the filler is one or more selected from the group consisting of glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, disodium carbonate), adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent, preferably the filler one or more selected from adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent.

[0098] In some embodiments, the article provided in (a) comprises titanium dioxide (TiCh). In these preferred embodiments, said TiC>2 is absent in the precipitated polyester obtained in (d) or is present in the precipitated polyester obtained in (d) in an amount in the range of from 0.001 to 1.0 weight-%, based on the total precipitated polyester obtained in (d) being 100 weight-%. In these preferred embodiments, said TiC>2, if present, is also present in the fiber prepared in (e).

[0099] Process conditions

[0100] In some embodiments of the method, T1 is a temperature in the range of from 110 to < 170°C, more preferably a temperature in the range of from 110 to 165 °C, more preferably a temperature in the range of from 120 to 160 °C, more preferably a temperature in the range of from 120 to 150 °C, more preferably in the range of from 151 to 160 °C.

[0101] In some embodiments of the method, T2 is a temperature in the range of from > 170°C to 200 °C, more preferably a temperature in the range of from 175 to 190 °C, more preferably a temperature in the range of from 180 to 190 °C.

[0102] In some embodiments of the method, (a), optionally (b), (c) and optionally (d) are done at a pressure in the range of from 800 to 200,000 hPa.

[0103] In some embodiments of the method, the contacting in (b) is done for a period of time of at least 5 minutes, more preferably in the range of from 5 minutes to 10 hours, more preferably in the range of from 5 minutes to 5 hours, more preferably in the range of from 5 minutes to 4 hours.

[0104] In some embodiments of the method, the contacting in (c) is done for a period of time of at least 0.1 hours, more preferably in the range of from 1 minute to 10 hours, more preferably in the range of from 1 minute to 2 hours, more preferably in the range of from 5 minutes to 1 hour.

[0105] In some embodiments of the method, the contacting in (b) and / or (c) is done with a in mass based ratio solvent system : polymer blend provided in (a) or residue obtained in (b) in the range of 1 : 1 to 100: 1 , more preferably in the range of from 1 :1 to 20: 1. In some embodiments of the method, at least steps (b) and (c), more preferably all steps, are done in an inert atmosphere, more preferably in the presence of an inert gas, wherein the inert gas is preferably selected from the group consisting of argon, helium, neon, nitrogen and mixtures of two or more of these inert gases, preferably comprises at least nitrogen, more preferably the inert gas is nitrogen.

[0106] In some embodiments of the method, at least steps (b) and (c), more preferably all steps, are done batch-wise or continuous.

[0107] In some embodiments, the method comprises

[0108] (I) providing polyester obtained from step (d), (y.1 ), (y.2), (y.3), (y.4) or (z), preferably from step (y.3), (y.4) or (z);

[0109] (II) preparing a food packaging, a beverage packaging, a clothing, a foot wear, a wire, or a cable from the polyester provided in (I).

[0110] 2ndaspect - Polyester

[0111] A second aspect of the invention is directed to a polyester obtained or obtainable from the process of the first aspect, more preferably obtained or obtainable from step (d), (y.1 ), (y.2), (y.3), y(.4) or (z), more preferably from step (y.3), (y.4) or (z). All details, embodiments and preferred embodiments disclosed above in the section related to the first aspect apply also for the second aspect.

[0112] 3rdaspect - Use

[0113] In a third aspect, the invention is related to the use of the polyester of the second aspect for textile applications, fiber applications, packaging applications, plastic applications, automotive applications, electronic applications, preferably for the production of food packaging, beverage packaging, clothing, foot wear, wire, cable, wherein preferably for textile applications, fiber applications, packaging applications, plastic applications, more preferably for the production of food packaging, beverage packaging, clothing and foot wear. All details, embodiments and preferred embodiments disclosed above in the section related to the first aspect or in the section related to the second aspect apply also for the third aspect.

[0114] 4thaspect - method for preparing a product

[0115] A fourth aspect of the invention is directed to a method for preparing a product comprising (I) providing polyester of the second aspect;

[0116] (II) preparing a textile, a fiber, a packaging, a plastic, an automotive part, an electronic part from the polyester provided in (I).

[0117] All details, embodiments and preferred embodiments disclosed above in the section related to the first aspect or in the section related to the second aspect apply also for the fourth aspect.

[0118] Preferably, in (II) a part of a car; preferably cylinder head cover, engine cover, housing for charge air cooler, charge air cooler flap, intake pipe, intake manifold, connector, gear wheel, fan wheel, cooling water box, housing, housing part for heat exchanger, coolant cooler, charge air cooler, thermostat, water pump, radiator, fastening part, part of battery system for electromobility, dashboard, steering column switch, seat, headrest, center console, transmission component, door module, cover for car A, B, C or D pillar, spoiler, door handle, exterior mirror, windscreen wiper, windscreen wiper protection housing, decorative grill, cover strip, roof rail, window frame, sunroof frame, antenna panel, headlight and taillight, engine cover, cylinder head cover, intake manifold, airbag, cushion, or coating; a cloth; preferably shirt, trousers, pullover, boot, shoe, shoe sole, tight or jacket; an electrical part; preferably electrical or electronic passive or active component, circuit board, printed circuit board, housing component, foil, line, switch, plug, socket, distributor, relay, resistor, capacitor, inductor, bobbin, lamp, diode, LED, transistor, connector, regulator, integrated circuit (IC), processor, controller, memory, sensor, microswitch, microbutton, semiconductor, reflector housing for light-emitting diodes (LED), fastener for electrical or electronic component, spacer, bolt, strip, slide-in guide, screw, nut, film hinge, snap hook (snap-in), or spring tongue; a consumer, agricultural product or pharmaceutical product; preferably tennis string, climbing rope, bristle, brush, artificial grass, 3D printing filament, grass trimmer, zipper, hook and loop fastener, paper machine clothing, extrusion coating, fishing line, fishing net, offshore line and rope, vial, syringe, ampoule, bottle, sliding element, spindle nut, chain conveyor, plain bearing, roller, wheel, gear, roller, ring gear, screw and spring dampers, hose, pipeline, cable sheathing, socket, switch, cable tie, fan wheel, carpet, box or bottle for cosmetics, mattress, cushion, insulation, detergent, dishwasher tabs or powder, shampoo, body wash, shower gel, soap, fertilizer, fungicide, or pesticide; a packaging for the food industry; preferably mono- or multi-layer blown film, cast film (mono- or multi-layer), biaxially stretched film, or laminating film; or a part of a construction; preferably a rotor blade, insulating material, frame, housing, wall, coating, or separating wall, is prepared. All details, embodiments and preferred embodiments disclosed above in the section related to the first to third aspect apply also for the fourth aspect.

[0119] 5thaspect - Method focused on obtaining a separated fraction comprising the further polymer of and optionally the second polymer

[0120] A fifth aspect of the invention relates to the method of the first aspect, wherein (b) comprises: (b.1) contacting the article with the solvent system at a temperature T1 of < 170 °C, thereby obtaining a solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer, and optionally in filler or part of the filler; and a residue of the article, which is depleted of said further polymer, optionally of colorant, optionally of second polymer and optionally of filler or part of the filler and comprises the polyester, optionally the metal containing part of (ii), optionally the filler or a part of the filler and optionally the third polymer;

[0121] (b.2) separating the solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer and optionally in filler or part of the filler, obtained in (b.1) from the residue, preferably by a physical separation method, thereby obtaining a separated solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer, and optionally in filler or part of the filler, compared to the solvent system provided in (a); and

[0122] (b.3) separating at least the further polymer of (ii) and optionally the second polymer from the solvent system, thereby obtaining a separated fraction comprising the further polymer of (ii) and optionally the second polymer.

[0123] All details, embodiments and preferred embodiments disclosed above in the section related to the first to fourth aspect apply also for the fifth aspect.

[0124] 6thaspect - conversion of the re-obtained polyester

[0125] A sixth aspect relates to a method, preferably according to according to the first or the fifth aspect, comprising the further step: converting the re-obtained polyester obtained by the method according to the first or the firth aspect to obtain a polymer product.

[0126] All details, embodiments and preferred embodiments disclosed above in the section related to the first to fifth aspect apply also for the sixth aspect.

[0127] 7thaspect - Method focused on conversion of a residue

[0128] A seventh aspect relates to a method, preferably according to the first or the fifth aspect, comprising the further step: converting a residue obtainable by or obtained by the method according to the first or the fifth aspect, preferably obtained or obtainable from step (d), more preferably the residue comprising at least third polymer obtainable by or obtained by the method according to according to a the first or the fifth aspect, preferably obtained or obtainable from step (d), or the further polymer of (ii) and optionally the second polymer obtained in (b.3), to obtain one or more monomer, polymer or polymer product.

[0129] All details, embodiments and preferred embodiments disclosed above in the section related to the first to sixth aspect apply also for the seventh aspect.

[0130] Preferably, the monomer is a di- or polyol; more preferably butandiol; aldehyde; preferably formaldehyde; di- or polyisocyanate; preferably methylene diphenyl diisocyanate (MDI), polymeric methylene diphenyl diisocyanate (pMDI), toluene diisocyanate (TDI), hexamethylenediisocyanate (HDI) or isophoronediisocyanate (IPDI); amide; preferably caprolactam; alkene; preferably styrene, ethene and norbornene; alkyne, (di)ester; preferably methyl methacrylate; mono or diacid; preferably adipic acid or terephthalic acid; diamine; preferably hexamethylenediamine, nonanediamine; or sulfones; preferably 4, 4'-dichlorodiphenyl sulfone.

[0131] Preferably, the polymer is and / or the polymer product comprises polyamide (PA); preferably PA 6 or PA 66; polyisocyanate polyaddition product; preferably polyurethane (Pll), thermoplastic polyurethane (TPU), polyurea or polyisocyanurate (PIR); low-density polyethylene (LDPE), high- density polyethylene (HDPE), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinyl acetate (PVA), polystyrene (PS), poly acrylonitrile butadiene styrene (ABS), poly styrene acrylonitrile (SAN), poly acrylate styrene acrylonitrile (ASA), polytetrafluoroethylene (PTFE), poly(methyl acrylate) (PMA), poly(methyl methacrylate) (PMMA), polybutadiene (BR, PBD), poly(cis-1 ,4-isoprene), poly(trans-1 ,4-isoprene), polyoxymethylene (POM), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polybutylene adipate coterephthalate (PBAT), polyester (PES), polyether sulfone (PESLI), polyhydroxyalkanoate (PHA), poly-3-hy- droxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), polyhydroxyoctanoate (PHO), polylactic acid (PLA), polysulfone (PSU), polyphenylene sulfone (PPSLI), polycarbonate (PC), polyether ether ketone (PEEK), poly(p-phe- nylene oxide) (PPO), poly(p-phenylene ether) (PPE); or copolymer or mixture thereof.

[0132] Preferably, the polymer and / or the polymer product is / are or is / are a part of: a part of a car; preferably cylinder head cover, engine cover, housing for charge air cooler, charge air cooler flap, intake pipe, intake manifold, connector, gear wheel, fan wheel, cooling water box, housing, housing part for heat exchanger, coolant cooler, charge air cooler, thermostat, water pump, radiator, fastening part, part of battery system for electromobility, dashboard, steering column switch, seat, headrest, center console, transmission component, door module, cover for car A, B, C or D pillar, spoiler, door handle, exterior mirror, windscreen wiper, windscreen wiper protection housing, decorative grill, cover strip, roof rail, window frame, sunroof frame, antenna panel, headlight and taillight, engine cover, cylinder head cover, intake manifold, airbag, cushion, or coating; a cloth; preferably shirt, trousers, pullover, boot, shoe, shoe sole, tight or jacket; an electrical part; preferably electrical or electronic passive or active component, circuit board, printed circuit board, housing component, foil, line, switch, plug, socket, distributor, relay, resistor, capacitor, inductor, bobbin, lamp, diode, LED, transistor, connector, regulator, integrated circuit (IC), processor, controller, memory, sensor, microswitch, microbutton, semiconductor, reflector housing for light-emitting diodes (LED), fastener for electrical or electronic component, spacer, bolt, strip, slide-in guide, screw, nut, film hinge, snap hook (snap-in), or spring tongue; a consumer, agricultural product or pharmaceutical product; preferably tennis string, climbing rope, bristle, brush, artificial grass, 3D printing filament, grass trimmer, zipper, hook and loop fastener, paper machine clothing, extrusion coating, fishing line, fishing net, offshore line and rope, vial, syringe, ampoule, bottle, sliding element, spindle nut, chain conveyor, plain bearing, roller, wheel, gear, roller, ring gear, screw and spring dampers, hose, pipeline, cable sheathing, socket, switch, cable tie, fan wheel, carpet, box or bottle for cosmetics, mattress, cushion, insulation, detergent, dishwasher tabs or powder, shampoo, body wash, shower gel, soap, fertilizer, fungicide, or pesticide; a packaging for the food industry; preferably mono- or multi-layer blown film, cast film (mono- or multi-layer), biaxially stretched film, or laminating film; or a part of a construction; preferably a rotor blade, insulating material, frame, housing, wall, coating, or separating wall.

[0133] Preferably, the content of the third polymer and / or the further polymer and / or the second polymer in the monomer, polymer and / or polymer product is 1 weight-% or more, preferably 2 weight-% or more, more preferably 5 weight-% or more, more preferably 15 weight-% or more, more preferably 30 weight-% or more, more preferably 40 weight-% or more, more preferably 60 weight-% or more, more preferably 80 weight-% or more, more preferably 90 weight-% or more, more preferably 95 weight-% or more; and / or wherein the content of the third polymer and / or the further polymer and / or the second polymer in the monomer, polymer and / or polymer product is 100 weight-% or less, preferably 95 weight- % or less, more preferably 90 weight-% or less, more preferably 50 weight-% or less, more preferably 25 weight-% or less, more preferably 10 weight-% or less; and preferably wherein the content is determined based on identity preservation and / or segregation and / or mass balance and / or book and claim chain of custody models, preferably based on mass balance, preferably the International Sustainability and Carbon Certification (ISCC) standard.

[0134] The present invention is further illustrated by the following set of embodiments and combinations of embodiments resulting from the dependencies and back-references as indicated. In particular, it is noted that in each instance where a range of embodiments is mentioned, for example in the context of a term such as "The method of any one of embodiments 1 to 4", every embodiment in this range is meant to be explicitly disclosed for the skilled person, i.e. the wording of this term is to be understood by the skilled person as being synonymous to "The method of any one of embodiments 1 , 2, 3 and 4". Further, it is explicitly noted that the following set of embodiments represents a suitably structured part of the general description directed to preferred aspects of the present invention, and, thus, suitably supports, but does not represent the claims of the present invention.

[0135] 1 . A method for recovering polyester from an article, which comprises

[0136] (i) a polyester;

[0137] (ii) a metal containing part and / or a part comprising a further polymer selected from polyacetal, polyvinyl chloride, and mixtures thereof; the method comprising:

[0138] (a) providing the article and providing a solvent system;

[0139] (b) optionally contacting the article with the solvent system at a temperature T1 of < 170 °C, thereby obtaining a solvent system, which is enriched in dissolved further polymer of (ii), and a residue of the article, which is depleted of said further polymer and comprises the polyester and optionally the metal containing part of (ii);

[0140] (c) contacting the article provided in (a) or the residue of the article optionally_obtained in (b) with a solvent system at a temperature T2 of > 170 °C, thereby obtaining a solvent system, which is enriched in dissolved polyester compared to the solvent system provided in (a), and optionally a residue of the article, which is depleted of polyester and comprises the metal containing part of (ii);

[0141] (d) precipitating the polyester from the solvent system, which is enriched in dissolved polyester, obtained in (c), thereby obtaining a precipitated polyester and a solvent system, which is depleted in dissolved polyester.

[0142] 2. The method of embodiment 1 , wherein the metal containing part and / or part comprising a further polymer is / are closing and / or decoration means, preferably selected from the group consisting of zipper, ribbon, cramp, button, sequin, patch, hook, eyelet, grommet, buckle, clasp and mixtures of two or more thereof, preferably from the group consisting of zipper, button, sequin and mixtures of two or more thereof.

[0143] 3. The method of embodiment 1 or 2, wherein the metal of the metal part is selected from the group consisting of brass, silver, nickel silver, aluminum, gold, old brass, nickel and mixtures of two or more thereof.

[0144] 4. The method of any one of embodiments 1 to 3, wherein the polyacetal of the part comprising a further polymer is selected from the group consisting of polyoxymethylene homopolymer, polyoxymethylene copolymer and mixtures of polyoxymethylene homopolymer and polyoxymethylene copolymer, wherein polyoxymethylene copolymer is preferably polyoxymethylene, wherein in the range of from 0.1 to 1.5 % of the -CH2O- groups are replaced by -CH2CH2O- groups.

[0145] 5. The method of any one of embodiments 1 to 4, wherein neither between (a) and (b) nor between (b) and (c), nor -in the absence of (b)- between (a) and (c) a separation of metal containing part and / or part comprising a further polymer from the polyester (i) of the article is done (no pre-processing).

[0146] 6. The method of any one of embodiments 1 to 5, wherein neither between (a) and (b) nor - in the absence of (b)- between (a) and (c), a mechanical pre-treatment, preferably a shredding, is done.

[0147] 7. The method of any one of embodiments 1 to 6, wherein the article further comprises

[0148] (iii) one or more component(s) selected from the group consisting of a second polymer, a third polymer, a colorant and a filler, wherein second polymer and third polymer are different from each other and different from the polyester of (i) and from the further polymer of the parts comprising a further polymer of (ii).

[0149] 8. The method of embodiment 7, wherein second polymer and / or colorant, if present, is / are dissolved in optional step (b) so that the obtained solvent system, which is enriched in dissolved further polymer of the parts comprising a further polymer of (ii) is also enriched in second polymer and / or in colorant, and the residue of the article obtained in (b), which is depleted of said further polymer and comprises the polyester and optionally the metal containing part of the closing and / or decoration means (ii) is also depleted of the second polymer and / or the colorant. 9. The method of embodiment 7 or 8, wherein the third polymer, if present, is not dissolved in optional step (b) and not dissolved in step (c), so that the residue of the article obtained in (b), which is depleted of further polymer and comprises the polyester and optionally the metal containing part of (ii) also comprises the third polymer; and preferably the residue of the article obtained in (c), which is depleted of polyester and comprises the metal containing parts of (ii) also comprises the third polymer.

[0150] 10. The method of any one of embodiments 7 to 9, wherein the filler if present, is optionally partially or completely dissolved in optional step (b) and / or optionally partially or completely dissolved in step (c), so that the residue of the article obtained in (b), which is depleted of further polymer and comprises the polyester and optionally the metal containing part of (ii) also optionally comprises the filler or a part of the filler; and preferably the residue of the article obtained in (c), which is depleted of polyester and which optionally comprises the metal containing parts of (ii), optionally also comprises the filler or a part of the filler.

[0151] 11. The method of any one of embodiments 1 to 10, wherein the article is a textile article, preferably a baggage or a clothing or a part of a baggage or a clothing, a clothing preferably being selected from the group consisting of swim wear, shirt, trousers, pullover, blouse, under wear, sock, jacket, skirt, top, sweater, short, overall, coverall, jumpsuit, romper, suits, pajama, lingerie, coat, glove, and vest; a baggage preferably being selected from the group consisting of hip bag, backpack, bag, pouche, and suitcase.

[0152] 12. The method of any one of embodiments 1 to 11 , wherein the article is selected from the group consisting of a toying article, a sport equipment article, an outdoor equipment article or combined articles thereof.

[0153] 13. The method of any one of embodiments 1 to 12, comprising, if (b) is conducted, after (b) and before (c):

[0154] (v) washing the residue of the article obtained in (b) with a washing solvent, thereby obtaining a washed residue, which is depleted of said further polymer and comprises the polyester and optionally the metal containing part of (ii) provided in (a);

[0155] (w) optionally drying the washed residue obtained in (v).

[0156] 14. The method of any one of embodiments 1 to 13, comprising after (c), if a residue is present, and before step (d)

[0157] (x.1) separating the solvent system, which is enriched in dissolved polyester and comprises optionally the filler or a part of the filler obtained in (c), from the residue of the polymer blend, wherein the separation is preferably done by heated filtration, more preferably by heated filtration at a temperature T3 in the range of from T2 minus 20 °C to T2 plus 20 °C (T3 = T2 ± 20°C), more preferably at a temperature T3 in the range of from T2 minus 10 °C to T2 plus 10 °C (T3 = T2 ± 10°C), thereby obtaining the solvent system, which is enriched in dissolved polyester and comprises optionally the filler or a part of the filler, and a separated residue;

[0158] (x.2) optionally contacting said separated residue of the polymer blend obtained in (x.1) with solvent system, preferably at a temperature T3 as defined above in (x.1), followed by filtration, preferably heated filtration at a temperature T3 as defined above in (x.1), thereby obtaining a residue of the polymer blend, which is further depleted of polyester and comprises one or more of the third polymer, the filler or a part of the filler; and a solvent system, which contains further amount of the polyester and comprises optionally the filler or a part of the filler;

[0159] (x.3) optionally combining the solvent system, which contains the further amount of the polyester and comprises optionally the filler or a part of the filler obtained in (x.2) with the solvent system, which is enriched in dissolved polyester and comprises optionally the filler or a part of the filler, separated in (x.1); wherein precipitation in (d) is done based on the separated solvent system obtained in (x.1) or based on the combined solvent system obtained in (x.3).

[0160] 15. The method of any one of embodiments 1 to 14 comprising after (d)

[0161] (y.1) separating the precipitated polyester obtained in (d) from the solvent system, which is depleted in dissolved polyester and comprises optionally the filler or a part of the filler, thereby obtaining a precipitated polyester and the solvent system, which is depleted in dissolved polyester and which optionally comprises the filler or a part of the filler;

[0162] (y.2) optionally washing the precipitated polyester obtained in (y.1);

[0163] (y.3) drying the precipitated polyester obtained in (y.1) or the washed precipitated polyester obtained in (y.2), thereby obtaining a dried (washed) precipitated polyester:

[0164] (y.4) optionally pelletizing the dried (washed) precipitated polyester obtained in (y.3), thereby obtaining a pelletized polyester.

[0165] 16. The method of any one of embodiments 1 to 15 comprising after (d) or after (y.3) or after (y.4), preferably after (y.3) or after (y.4)

[0166] (z) increasing the intrinsic viscosity of the precipitated polyester obtained in (d) or of the dried (washed) precipitated polyester obtained in (y.3) or of the pelletized polyester obtained in (y.4). The method of any one of embodiments 1 to 16, wherein precipitation in (d) comprises cooling the solvent system obtained in (c), which is enriched in dissolved polyester compared to the solvent system provided in (a), from T2 to a temperature below 140°C, wherein the cooling is done so that the temperature of the solvent system, which is enriched in dissolved polyester, is within the temperature range of from 160 to 145 °C for a period of time of at least 5 minutes, preferably at least 10 minutes, more preferably in the range from 5 to 120 minutes, more preferably in the range of from 10 to 100 minutes, more preferably in the range of from 15 to 100 minutes. The method of embodiment 17, wherein cooling in (d) is done so that the solvent system, which is enriched in dissolved polyester, has within the temperature range of from 160 to 145 °C a viscosity in the range of from 1 to 12 Pa s, preferably in the range of from 1 to 10 Pa s, determined according to DIN EN ISO 2555 (2018-09). The method of embodiment 17 or 18, wherein cooling is done with a cooling rate of < 3.0 °C / min, preferably < 1.5 °C / min, more preferably in the range of from 0.05 to 3.0 C / min, more preferably in the range of from 0.13 to 3.0 °C / min, more preferably in the range of from 0.15 to 1.5 °C / min, more preferably in the range of from 0.15 to 1.0 °C / min. The method of any one of embodiments 17 to 19, wherein the cooling of the solvent system in (d) is done from T2 to a temperature below 100°C. The method of any one of embodiments 17 to 20, wherein the cooling of the solvent system in (d) is done without addition of an anti-solvent. The method of any one of embodiments 1 to 21 , wherein the solvent system comprises one or more solvent(s), wherein

[0167] (s.1) the solvent system has Hansen solubility parameters with respect to energy from dispersion forces between molecules (5DSS), energy from dipolar intermolecular force between molecules (5PSS) and energy from hydrogen bonds between molecules (5HSS), which fullfill equitation 1

[0168] (8.8)2> 4(6Dss-20)2+ (5PSS-11.8)2+ (5Hss-4.5)2

[0169] [equitation 1];

[0170] (s.2) each solvent of the solvent system has a boiling point at 1013 hPa of at least 160 °C; and (s.3) solvents having a functional group selected from the group consisting of hydroxyl (OH), amino (NH2), carboxyl (COOH), and thiol (SH) are excluded.

[0171] 23. The method of any one of embodiments 1 to 22, wherein at least 90 weight-%, preferably at least 95 weight-%, more preferably at least 98 weight-%, more preferably at least 99 weight-%, of the solvent system consist of one solvent system, which fulfills equitation 1 , wherein in cases where the solvent system consists of only one solvent system, the temperature T is a temperature at least 7K below the boiling temperature of said one solvent.

[0172] 24. The method of any one of embodiments 1 to 23, wherein at least 90 weight-%, preferably at least 95 weight-%, more preferably at least 98 weight-%, more preferably at least 99 weight-%, of the solvent system consist of two or more solvent(s), wherein the respective mixture fulfill(s) equitation 1.

[0173] 25. The method of any one of embodiments 1 to 24, wherein the one or more solvent(s) is / are selected from the group consisting of N,N-dimethylbenzamide, N,N-dimethylphenyla- cetamide, 1,4-benzoquinone, acetophenone, dimethyl terephthalate, 1,3,5-trimethoxyben- zene, 2-phenylacetophenone, N-methylcaprolactam, methylbenzoate, methyl-4-methox- ybenzoate, butylene carbonate, N-ethylpyrrolidone, benzophenone, di-benzyl malonate, N-ethyl-caprolactam, methyl 2-(5-oxotetrahydrofuran-3-yl)acetate (FAME), methyl 2-(5- oxotetrahydrofuran-2-yl)acetate, propiophenone, N-methoxypropyl-pyrrolidone, 1 ,4-cyclo- hexanedione, cyclohexane-carbonate, N-methoxyethyl-pyrrolidone, N,N-diethylphenyla- cetamide, phenyl acetate, 1-(2-hydroxyethyl)pyrrolidin-2-one acetate (HEPAc), N,N-dieth- ylbenzamide, isopropyl-benzoate, cyclohexyl phenyl ketone, phenylacetic acid ethylester, phenylacetat.N-methyl-morpholine, benzyl-propionate, benzylacetate, Neopentyl-glycol- dibenzoate, tetrahydrofurfuryl acetate, N-methyl-imidazole, benzyl butyrate, 2-pyrrolidone, 2-phenoxyethanol propionate, 2-phenoxyethyl isobutyrate, N,N-dipropylbenzamide, N,N- dimethylacetamide, N,N-diethylacetamide, dihydrolevoglucosenon (Cyrene), propylenecarbonate, caprolactone, dimethylisosorbide, N-butylpyrrolidone, t-butylpyrrolidone, me- thyl-1-methyl-5-oxopyrrolidine-3-carboxylate (MMOC), gamma-valerolactone (GVL), delta- valerolactone, gamma butyrolactone, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodiasolv Polarclean), caprolactam, phen ethyl acetate, methyl phenylacetate, benzyl benzoate, N,N-dimethyllactamide (Agnique AMD 3L), 1,3-dimethyl-2-imidazolidinone (DMI), and dimethyl sulfoxide (DMSO).

[0174] 26. The method of any one of embodiments 1 to 25, wherein the one or more solvent(s) is / are selected from the group consisting of dihydrolevoglucosenon (Cyrene), propylenecarbonate, caprolactone, dimethylisosorbide, N-butylpyrrolidone, t-butylpyrrolidone, methyl-1- methyl-5-oxopyrrolidine-3-carboxylate (MMOC), gamma-valerolactone (GVL), Delta- valerolactone, gamma butyrolactone, dimethylsulfoxide, methyl 5-(dimethylamino)-2-me- thyl-5-oxopentanoate (RhodiasolvOPolarclean), caprolactam, phen ethyl acetate, methyl phenylacetate, benzyl benzoate, phenyl benzoate, methyl benzoate, propyl benzoate, and dimethyl sulfoxide (DMSO).

[0175] 27. The method of any one of embodiments 1 to 26, wherein the one or more solvent(s) of the solvent system is / are selected from the group consisting of propylenecarbonate, N-bu- tylpyrrolidone, t-butylpyrrolidone, methyl-1-methyl-5-oxopyrrolidine-3-carboxylate (MMOC), Delta-valerolactone, gamma butyrolactone, methyl 5-(dimethylamino)-2-methyl- 5-oxopentanoate (RhodiasolvOPolarclean), caprolactam, phenethyl acetate, methyl phenylacetate, benzyl benzoate, phenyl benzoate, methyl benzoate, propyl benzoate and GVL.

[0176] 28. The method of any one of embodiments 1 to 27, wherein the one or more solvent(s) is / are selected from the group consisting of propylenecarbonate, N-butylpyrrolidone, t-butylpyr- rolidone, methyl-1-methyl-5-oxopyrrolidine-3-carboxylate (MMOC), Delta-valerolactone, gamma butyrolactone, methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (Rhodi- asolvOPolarclean), caprolactam, phen ethyl acetate, methyl phenylacetate, benzyl benzoate, phenyl benzoate, methyl benzoate, and propyl benzoate.

[0177] 29. The method of any one of embodiments 1 to 28, wherein the one or more solvent(s) of the solvent system is / are selected from the group consisting of propylenecarbonate, N-bu- tylpyrrolidone, t-butylpyrrolidone, methyl-1-methyl-5-oxopyrrolidine-3-carboxylate (MMOC), methyl 5-(dimethylamino)-2-methyl-5-oxopentanoate (RhodiasolvOPolarclean), phenethyl acetate, and GVL.

[0178] 30. The method of any one of embodiments 1 to 29, wherein the one or more solvent(s) is / are selected from the group consisting of propylenecarbonate, N-butylpyrrolidone, t-butylpyr- rolidone, methyl-1-methyl-5-oxopyrrolidine-3-carboxylate (MMOC), methyl 5-(dimethyla- mino)-2-methyl-5-oxopentanoate (RhodiasolvOPolarclean), and phen ethyl acetate.

[0179] 31 . The method of any one of embodiments 1 to 30, wherein ethyl benzoate and butyl benzoate are excluded as solvent(s).

[0180] 32. The method of any one of embodiments 1 to 31 , wherein (s.3a) solvents having a functional group selected from the group consisting of hydroxyl (OH), amino (NH2), secondary amine (-NH-), carboxyl (COOH), and thiol (SH) are excluded.

[0181] 33. The method of any one of embodiments 1 to 32, wherein the solvent system comprises gamma-valerolactone, wherein more preferably at least 50 weight-%, more preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least

[0182] 80 weight-%, more preferably at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 99 weight-% of the solvent system consists of gamma-valerolactone, based on the total weight of the solvent system being 100 weight-%.

[0183] 34. The method of any one of embodiments 1 to 33, wherein in optional step (b) the same solvent system as in (c) is used.

[0184] 35. The method of any one of embodiments 1 to 34, wherein the polyester is based on 1,4- butanediol or 1,2-ethandiol, more preferably the polyester according to (i) is selected from the group consisting of a polymer based on 1,4-butanediol and terephthalic acid (polybutylene terephthalate, PBT), a polymer based on 1,2-ethanediol and terephthalic acid (polyethylene terephthalate, PET), a copolymer of 1,4-butanediol, adipic acid and terephthalic acid (polybutylenadipat-terephthalat, PBAT), a polymer of 1,2-ethanediol and 2,5- furandicarboxylic acid (polyethylene furanoate, PEF) and mixtures of two or more of these (co)polymers, more preferably, the polyester comprises at least PET and / or PBT, more preferably the polyester is PET or PBT or a mixture of PET and PBT, more preferably the polyalkylene terephthalate based polymer comprises or is PET.

[0185] 36. The method of any one of embodiments 7 to 35, wherein the colorant is selected from the group consisting of dye and optical brightener and mixtures of dye and optical brightener.

[0186] 37. The method of any one of embodiments 7 to 36, wherein the second polymer is selected from the group consisting of polyurethane (Pll), polyethylene glycol (PEG), polytetrahydrofuran (pTHF), mixtures of these polymers and copolymers of these polymers, wherein the second polymer is more preferably Pll or a copolymer of Pll and PEG and / or pTHF, more preferably spandex.

[0187] 38. The method of any one of embodiments 1 to 37, wherein the third polymer is selected from polypropylene (PP), polyethylene (PE), polyamide (PA), natural polymer (such as cotton, viscose, linen) and mixtures of two or more thereof. 39. The method of any one of embodiments 7 to 38, wherein the filler is selected from the group consisting of glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, disodium carbonate), adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent.

[0188] 40. The method of embodiment 39, wherein the polyester comprises, preferably is PBT and the filler is one or more selected from the group consisting of glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, disodium carbonate), adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent, preferably the filler is one or more selected from glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, Na2COs).

[0189] 41. The method of embodiment 40, wherein the polyester comprises, preferably is PET and the filler is one or more selected from the group consisting of glass fiber, coal fiber, carbon black, inorganic salts (for example, talc, disodium carbonate), adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent, preferably the filler one or more selected from adhesive, thickener, antifoam agent, finishing agent (for example water / oil / stain repellent, flame retardant, anticrease agent, biocide), binder, surfactant (for example, softener, scouring agent, antistatic agent), desizing agent, bleaching agent, oxidant, UV filter, emulsionant, fixing agent, washing dispersant, profiling agent.

[0190] 42. The method of any one of embodiments 1 to 41 , wherein T1 is a temperature in the range of from 110 to < 170°C, preferably a temperature in the range of from 110 to 165 °C, more preferably a temperature in the range of from 120 to 160 °C, more preferably a temperature in the range of from 120 to 150 °C, more preferably in the range of from 151 to

[0191] 160 °C.

[0192] 43. The method of any one of embodiments 1 to 42, wherein T2 is a temperature in the range of from > 170°C to 200 °C, preferably a temperature in the range of from 175 to 190 °C, more preferably a temperature in the range of from 180 to 190 °C. The method of any one of embodiments 1 to 43, wherein (a), optionally (b), (c) and optionally (d) are done at a pressure in the range of from 800 to 200,000 hPa. The method of any one of embodiments 1 to 44, wherein the contacting in (b) is done for a period of time of at least 5 minutes, preferably in the range of from 5 minutes to 10 hours, more preferably in the range of from 5 minutes to 5 hours, more preferably in the range of from 5 minutes to 4 hours. The method of any one of embodiments 1 to 45, wherein the contacting in (c) is done for a period of time of at least 0.1 hours, preferably in the range of from 1 minute to 10 hours, more preferably in the range of from 1 minute to 2 hours, more preferably in the range of from 5 minutes to 1 hour. The method of any one of embodiments 1 to 46, wherein the contacting in (b) and / or (c) is done with a in mass based ratio solvent system : polymer blend provided in (a) or residue obtained in (b) in the range of 1:1 to 100:1 , preferably in the range of from 1 :1 to 20:1. The method of any one of embodiments 1 to 47, wherein at least steps (b) and (c), preferably all steps, are done in an inert atmosphere, preferably in the presence of an inert gas, wherein the inert gas is preferably selected from the group consisting of argon, helium, neon, nitrogen and mixtures of two or more of these inert gases, preferably comprises at least nitrogen, more preferably the inert gas is nitrogen. The method of any one of embodiments 1 to 48, wherein at least steps (b) and (c), preferably all steps, are done batch-wise or continuous. The method according to any one of embodiments 1 to 49 comprising

[0193] (I) providing polyester obtained from step (d), (y.1 ), (y.2), (y.3), (y.4) or (z), preferably from step (y.3), (y.4) or (z);

[0194] (II) preparing a food packaging, a beverage packaging, a clothing, a foot wear, a wire, or a cable from the polyester provided in (I). Polyester obtained or obtainable from the process of any one of embodiments 1 to 49, preferably obtained or obtainable from step (d), (y.1), (y.2), (y.3), (y.4) or (z), more preferably from step (y.3) or (y.4) or (z). Use of the polyester of embodiment 51 for textile applications, fiber applications, packaging applications, plastic applications, automotive applications, electronic applications, preferably for the production of food packaging, beverage packaging, clothing, foot wear, wire, cable, wherein preferably for textile applications, fiber applications, packaging applications, plastic applications, more preferably for the production of food packaging, beverage packaging, clothing and foot wear. A method for preparing a product comprising

[0195] (I) providing polyester of embodiment 51 ;

[0196] (II) preparing a textile, a fiber, a packaging, a plastic, an automotive part, an electronic part from the polyester provided in (I). The method of embodiment 53, wherein in (II) a part of a car; preferably cylinder head cover, engine cover, housing for charge air cooler, charge air cooler flap, intake pipe, intake manifold, connector, gear wheel, fan wheel, cooling water box, housing, housing part for heat exchanger, coolant cooler, charge air cooler, thermostat, water pump, radiator, fastening part, part of battery system for electromobility, dashboard, steering column switch, seat, headrest, center console, transmission component, door module, cover for car A, B, C or D pillar, spoiler, door handle, exterior mirror, windscreen wiper, windscreen wiper protection housing, decorative grill, cover strip, roof rail, window frame, sunroof frame, antenna panel, headlight and taillight, engine cover, cylinder head cover, intake manifold, airbag, cushion, or coating; a cloth; preferably shirt, trousers, pullover, boot, shoe, shoe sole, tight or jacket; an electrical part; preferably electrical or electronic passive or active component, circuit board, printed circuit board, housing component, foil, line, switch, plug, socket, distributor, relay, resistor, capacitor, inductor, bobbin, lamp, diode, LED, transistor, connector, regulator, integrated circuit (IC), processor, controller, memory, sensor, microswitch, microbutton, semiconductor, reflector housing for light-emitting diodes (LED), fastener for electrical or electronic component, spacer, bolt, strip, slide-in guide, screw, nut, film hinge, snap hook (snap-in), or spring tongue; a consumer, agricultural product or pharmaceutical product; preferably tennis string, climbing rope, bristle, brush, artificial grass, 3D printing filament, grass trimmer, zipper, hook and loop fastener, paper machine clothing, extrusion coating, fishing line, fishing net, offshore line and rope, vial, syringe, ampoule, bottle, sliding element, spindle nut, chain conveyor, plain bearing, roller, wheel, gear, roller, ring gear, screw and spring dampers, hose, pipeline, cable sheathing, socket, switch, cable tie, fan wheel, carpet, box or bottle for cosmetics, mattress, cushion, insulation, detergent, dishwasher tabs or powder, shampoo, body wash, shower gel, soap, fertilizer, fungicide, or pesticide; a packaging for the food industry; preferably mono- or multi-layer blown film, cast film (mono- or multi-layer), biaxially stretched film, or laminating film; or a part of a construction; preferably a rotor blade, insulating material, frame, housing, wall, coating, or separating wall, is prepared. The method of any one of embodiment 1 to 50, wherein (b) comprises:

[0197] (b.1) contacting the article with the solvent system at a temperature T1 of < 170 °C, thereby obtaining a solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer, and optionally in filler or part of the filler; and a residue of the article, which is depleted of said further polymer, optionally of colorant, optionally of second polymer and optionally of filler or part of the filler and comprises the polyester, optionally the metal containing part of (ii), optionally the filler or a part of the filler and optionally the third polymer;

[0198] (b.2) separating the solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer and optionally in filler or part of the filler, obtained in (b.1) from the residue, preferably by a physical separation method, thereby obtaining a separated solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer, and optionally in filler or part of the filler, compared to the solvent system provided in (a); and

[0199] (b.3) separating at least the further polymer of (ii) and optionally the second polymer from the solvent system, thereby obtaining a separated fraction comprising the further polymer of (ii) and optionally the second polymer. Method, preferably according to any one of embodiments 1 to 50 or 55, comprising the further step: converting the re-obtained polyester obtained by the Method according to any one of embodiments 1 to 46 or 50 to obtain a polymer product. Method, preferably according to any one of embodiments 1 to 50 or 55 or 56, comprising the further step: converting a residue obtainable by or obtained by the method according to any one of embodiments 1 to 49 or 54 or 55, preferably obtained or obtainable from step (d), more preferably the residue comprising at least third polymer obtainable by or obtained by the method according to according to any one of embodiments 1 to 49 or 54 or 55, preferably obtained or obtainable from step (d), or the further polymer of (ii) and optionally the second polymer obtained in (b.3), to obtain one or more monomer, polymer or polymer product.

[0200] 58. Method according to embodiment 57, wherein the monomer is a di- or polyol; preferably butandiol; aldehyde; preferably formaldehyde; di- or polyisocyanate; preferably methylene diphenyl diisocyanate (MDI), polymeric methylene diphenyl diisocyanate (pMDI), toluene diisocyanate (TDI), hexamethylenediisocyanate (HDI) or isophoronediisocyanate (IPDI); amide; preferably caprolactam; alkene; preferably styrene, ethene and norbornene; alkyne, (di)ester; preferably methyl methacrylate; mono or diacid; preferably adipic acid or terephthalic acid; diamine; preferably hexamethylenediamine, nonanediamine; or sulfones; preferably 4, 4'-dichlorodiphenyl sulfone.

[0201] 59. Method according to embodiment 57 or 58, wherein the polymer is and / or the polymer product comprises polyamide (PA); preferably PA 6 or PA 66; polyisocyanate polyaddition product; preferably polyurethane (Pll), thermoplastic polyurethane (TPU), polyurea or polyisocyanurate (PIR); low-density polyethylene (LDPE), high-density polyethylene (HDPE), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinyl acetate (PVA), polystyrene (PS), poly acrylonitrile butadiene styrene (ABS), poly styrene acrylonitrile (SAN), poly acrylate styrene acrylonitrile (ASA), polytetrafluoroethylene (PTFE), poly(methyl acrylate) (PMA), poly(methyl methacrylate) (PMMA), polybutadiene (BR, PBD), poly(cis-1 ,4-isoprene), poly(trans-1 ,4-iso- prene), polyoxymethylene (POM), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polybutylene adipate coterephthalate (PBAT), polyester (PES), polyether sulfone (PESLI), polyhydroxyalkanoate (PHA), poly-3-hydroxybutyrate (P3HB), poly-4-hy- droxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), polyhydroxyoctanoate (PHO), polylactic acid (PLA), polysulfone (PSU), polyphenylene sulfone (PPSLI), polycarbonate (PC), polyether ether ketone (PEEK), poly(p-phenylene oxide) (PPO), poly(p-phenylene ether) (PPE); or copolymer or mixture thereof.

[0202] 60. Method according to any one of embodiments 57 to 59, wherein the polymer and / or the polymer product is / are or is / are a part of: a part of a car; preferably cylinder head cover, engine cover, housing for charge air cooler, charge air cooler flap, intake pipe, intake manifold, connector, gear wheel, fan wheel, cooling water box, housing, housing part for heat exchanger, coolant cooler, charge air cooler, thermostat, water pump, radiator, fastening part, part of battery system for electromobility, dashboard, steering column switch, seat, headrest, center console, transmission component, door module, cover for car A, B, C or D pillar, spoiler, door handle, exterior mirror, windscreen wiper, windscreen wiper protection housing, decorative grill, cover strip, roof rail, window frame, sunroof frame, antenna panel, headlight and taillight, engine cover, cylinder head cover, intake manifold, airbag, cushion, or coating; a cloth; preferably shirt, trousers, pullover, boot, shoe, shoe sole, tight or jacket; an electrical part; preferably electrical or electronic passive or active component, circuit board, printed circuit board, housing component, foil, line, switch, plug, socket, distributor, relay, resistor, capacitor, inductor, bobbin, lamp, diode, LED, transistor, connector, regulator, integrated circuit (IC), processor, controller, memory, sensor, microswitch, microbutton, semiconductor, reflector housing for light-emitting diodes (LED), fastener for electrical or electronic component, spacer, bolt, strip, slide-in guide, screw, nut, film hinge, snap hook (snap-in), or spring tongue; a consumer, agricultural product or pharmaceutical product; preferably tennis string, climbing rope, bristle, brush, artificial grass, 3D printing filament, grass trimmer, zipper, hook and loop fastener, paper machine clothing, extrusion coating, fishing line, fishing net, offshore line and rope, vial, syringe, ampoule, bottle, sliding element, spindle nut, chain conveyor, plain bearing, roller, wheel, gear, roller, ring gear, screw and spring dampers, hose, pipeline, cable sheathing, socket, switch, cable tie, fan wheel, carpet, box or bottle for cosmetics, mattress, cushion, insulation, detergent, dishwasher tabs or powder, shampoo, body wash, shower gel, soap, fertilizer, fungicide, or pesticide; a packaging for the food industry; preferably mono- or multi-layer blown film, cast film (mono- or multi-layer), biaxially stretched film, or laminating film; or a part of a construction; preferably a rotor blade, insulating material, frame, housing, wall, coating, or separating wall. Method according to any one of embodiments 57 to 60, wherein the content of the third polymer and / or the further polymer and / or the second polymer in the monomer, polymer and / or polymer product is 1 weight-% or more, preferably 2 weight-% or more, more preferably 5 weight-% or more, more preferably 15 weight-% or more, more preferably 30 weight-% or more, more preferably 40 weight-% or more, more preferably 60 weight-% or more, more preferably 80 weight-% or more, more preferably 90 weight-% or more, more preferably 95 weight-% or more; and / or wherein the content of the third polymer in the monomer, polymer and / or polymer product is 100 weight-% or less, preferably 95 weight-% or less, more preferably 90 weight-% or less, more preferably 50 weight-% or less, more preferably 25 weight-% or less, more preferably 10 weight-% or less; and preferably wherein the content is determined based on identity preservation and / or segregation and / or mass balance and / or book and claim chain of custody models, preferably based on mass balance, preferably the International Sustainability and Carbon Certification (ISCC) standard.

[0203] The present invention is further illustrated by the following reference examples, comparative examples, and examples.

[0204] Examples

[0205] Methods

[0206] XRF Screening Analysis

[0207] XRF screening was performed directly on the sample material without preparation. The sample material was weighed into measurement cuvettes and the semi-quant program on a WD-XRF instrument was started after insertion of the cuvettes. The screening method serves as a rough clustering method, assigning elements to concentration ranges.

[0208] Infrared spectroscopy (IR):

[0209] FTIR-ATR spectra were obtained by FTIR spectrometers equipped with ATR units (Thermo Ni- colet iS50)

[0210] For measurement the samples were placed directly onto the ATR crystal without further preparation and were fixed with the unit’s stamp. All measurements were performed at room temperature (25 °C) using 32 scans and a resolution of 4 cm-1.

[0211] GPC (Gel-Permeation Chromatography):

[0212] Sample preparation:

[0213] Approximately 6 mg sample was dissolved in 5 ml eluent (hexafluorisopropanol + 0.05 weight-% trifluoro potassium acetate) over night. All sample solutions were filtered by a Millipore Millex FG (0.2 pm) filtered prior to injection. Sealed sample vials were placed into the auto sampler.

[0214] Experimental conditions:

[0215] An Agilent 1100 HPLC system, consisting of an isocratic pump, vacuum degasser, auto sampler and a column oven (35°C) was used. Furthermore, the Agilent system contained as detectors a Differential Refractive Index (DRI) and a variable Ultra Violet (UVW) Detector. Data acquisition and data processing of conventionally SEC data were done by WinGPC Unichrom, of PSS (Polymer Standard Services). A combination of a PL-HFIP guard (7.5 x 50 mm) column and 2 PL- HFIP Gel columns (7.5 x 300 mm, 9p) of Agilent were put in series. As an eluent, hexafluorisopropanol + 0.05 weight-% trifluoro potassium acetate was used as a flow rate of 1 ml / min. Of each sample solution 50pl was injected. The calibration was obtained by narrow molar mass distributed PMMA standards (Polymer Standard Services) having a molar mass range of M = 800 till M = 2.200.000 g / mol or M= 600 till M = 2.050.000 g / mol. Molar masses outside this range were extrapolated.

[0216] Chemicals

[0217] PET having Hansen parameters according to the 5thEdition 5.1.03 (2008) of the HANSEN

[0218] Solubility Parameters in Practice (HSPiP) of 5D = 18.2, 5P = 6.4 and 5H = 6.6

[0219] Hansen parameter GVL: 3D: 18.50, 8P: 14.17, 8H: 7.93 (from BIOVIA COSMOquick 2022)

[0220] Example 1 : Separation of PET from POM-based buttons a) Dissolution of POM-based buttons in GVL

[0221] POM-based buttons were placed in a reaction vessel (e.g. flask, tube, vessel). GVL was added (in mass-based ratio solvent : polymeric material 100:1 to 1 :1 , preferred 10:1-1 :1) and the mixture was heated by use of a suitable heating system (e.g. oil bath, heating blocks, mini-plant vessels) under inert gas atmosphere to a temperature at which the POM-based buttons dissolved upon visual inspection (about 140 °C). After 1-60 min, and the mixture was filtered (e.g. heated pressure filtration). The filtrate was allowed to cool-down to room temperature (20- 30 °C) wherein POM precipitated. The precipitated POM was filtrated and washed with a small amount of GVL. For an easy removal of GVL and a faster drying process of re-obtained POM powder, small amounts of acetone were optionally used in a second washing step. The thus obtained solid was dried (for example in a vacuum compartment dryer). b) Separation of POM-based buttons and PET textile in GVL

[0222] PET textile was cut / shredded into pieces and placed in a reaction vessel (e.g. flask, tube, vessel) together with POM-based buttons (1 :1 , w:w). GVL was added (in mass-based ratio solvent : polymeric material 100:1 to 1 :1 , preferred 10:1-1 :1) and the mixture was heated by use of a suitable heating system (e.g. oil bath, heating blocks, mini-plant vessels) under inert gas atmosphere to 140 °C. After 1-60 min, the POM-based buttons were completely dissolved upon visual inspection and the mixture was filtered (e.g. heated pressure filtration) whereby GVL enriched with POM was obtained as filtrate and undissolved PET textile pieces as filter cake. The filter cake was optionally further washed with a small amount of hot GVL. The filtrate was allowed to cool-down wherein POM precipitated. The precipitated POM was filtrated and washed with a small amount of GVL. The PET textile pieces were optionally also washed with a small amount of GVL. For an easy removal of GVL and a faster drying process of re-obtained POM powder and the PET textile pieces, small amounts of acetone were optionally used in a second washing step. The thus obtained POM solid and PET textile pieces were dried (for example in a vacuum compartment dryer). The IR spectra of obtained POM solid and PET textile pieces in comparison to reference spectra of virgin POM and PET are shown in Fig. 1. It was shown based on IR spectroscopy that both POM and PET were re-obtained in unamended form.

[0223] Example 2: Separation of PET from PVC-based sequins a) Dissolution of PVC-based sequins in GVL

[0224] PVC-based sequins were placed in a reaction vessel (e.g. flask, tube, vessel). GVL was added (in mass-based ratio solvent : polymeric material 100:1 to 1 :1 , preferred 10:1-1 :1) and the mixture was heated by use of a suitable heating system (e.g. oil bath, heating blocks, mini-plant vessels) under inert gas atmosphere to a temperature at which the PVC-based sequins dissolved upon visual inspection (about 120 °C). After 1-60 min, the mixture was filtered (e.g. heated pressure filtration). The filtrate was allowed to cool-down to room temperature (20- 30 °C). The PVC was either obtained by addition of iPrOH to the filtrate and subsequent filtration or via distillation of GVL. The reobtained PVC (of both options) was washed with a small amount of iPrOH. The obtained PVC (of both options) was dried (for example in a vacuum compartment dryer). b) Separation of PVC-based sequins and PET textile in GVL

[0225] PET textile was cut / shredded into pieces and placed in a reaction vessel (e.g. flask, tube, vessel) together with PVC-based sequins (3:1 , w:w). GVL was added (in mass-based ratio solvent : polymeric material 100:1 to 1 :1 , preferred 10:1-1 :1) and the mixture was heated by use of a suit- able heating system (e.g. oil bath, heating blocks, mini-plant vessels) under inert gas atmosphere to 120 °C. After 1-60 min, the PVC-based sequins were dissolved upon visual inspection and the mixture was filtered (e.g. heated pressure filtration) whereby GVL enriched with PVC was obtained as filtrate and PET textile pieces as filter cake. The filter cake was optionally further washed with a small amount of hot GVL. The PVC was either obtained by addition of iPrOH to the filtrate and subsequent filtration or via distillation of GVL. The reobtained PVC (of both options) was washed with a small amount of iPrOH. The PET textile pieces were optionally washed with a small amount of GVL. For an easy removal of GVL and a faster drying process, small amounts of acetone were optionally used in a second washing step. The obtained products PVC (from both options) and PET textile pieces were dried (for example in a vacuum compartment dryer). The IR spectra of obtained PVC and PET textile pieces are shown in Fig. 2 (PVC precipitated with iPrOH) and Fig. 3 (PVC obtained after distillation). It was shown based on IR spectroscopy that both PVC and PET were re-obtained in unamended form. The reobtained PVC (obtained after distillation) still had residuals amounts of left-over solvent GVL and residual amounts of PET (illustrated with arrows in Fig. 3). The later was due to the fact, that the oligomers of the starting material PET dissolved at the same temperature as the PVC. The reobtained PVC was not precipitated from GVL by addition of an anti-solvent (e.g. iPrOH), but was obtained by removing the GVL via distillation. Thus, the dissolved PET oligomers were detected in the PVC.

[0226] Example 3: Separation of PET from metal buttons

[0227] PET textile was cut / shredded into pieces and placed in a reaction vessel (e.g. flask, tube, vessel) together with metal-based buttons (2:1 , w:w). GVL was added (in mass-based ratio solvent : polymeric material and metal button 100:1 to 1 :1 , preferred 10:1-1 :1) and the mixture was heated by use of a suitable heating system (e.g. oil bath, heating blocks, mini-plant vessels) under inert gas atmosphere to 185 °C. After 1-60 min, the PET textile was dissolved upon visual inspection and the mixture was filtered (e.g. heated pressure filtration) whereby GVL enriched with PET was obtained as filtrate and undissolved metal-based buttons as filter cake. The filter cake was optionally further washed with a small amount of hot GVL. The filtrate was allowed to cool-down to room temperature (20-30 °C) wherein PET precipitated. The precipitated PET was filtrated and washed with a small amount of GVL. The metal buttons were optionally washed with a small amount of GVL. For an easy removal of GVL and a faster drying process of re-ob- tained PET powder, small amounts of acetone were optionally used in a second washing step. The thus obtained PET powder was dried (for example in a vacuum compartment dryer). With the use of x-ray fluorescence spectrometry it could be shown that the metal button did not leach any metals that are now enriched in the re-obtained PET powder. The only metal-based element that was found was Ti (<0.1 %), which derived from TiC>2 present in the initial article.

[0228] Example 4: Recovery of PET from textile and PET containing applications

[0229] PET textile was cut / shredded into pieces and placed in a reaction vessel (e.g. flask, tube, vessel) together with zipper pieces (ribbon inclusive cramps) (3:1 , w:w). GVL was added (in massbased ratio solvent : polymeric material and zipper 100:1 to 1 :1 , preferred 10:1-1 :1) and the mixture was heated by use of a suitable heating system (e.g. oil bath, heating blocks, mini-plant vessels) under inert gas atmosphere to 185 °C. After 1-60 min, the PET textile was dissolved upon visual inspection and the mixture was filtered (e.g. heated pressure filtration) whereby GVL enriched with PET was obtained as filtrate. The filter cake was optionally further washed with a small amount of hot GVL. The filtrate was allowed to cool-down to room temperature (20- 30 °C) wherein PET precipitated. The precipitated PET was filtrated and washed with a small amount of GVL. For an easy removal of GVL and a faster drying process of re-obtained PET powder, small amounts of acetone were optionally used in a second washing step. The thus obtained PET powder was dried (for example in a vacuum compartment dryer) and analyzed via GPC-HPLC. The results are shown in Table 1 below.

[0230] Table 1

[0231] Mn and Mw values from GPC-HPLC analysis of starting materials and of re-obtained PET

[0232] It was shown that the number average molecular weight Mn of the re-obtained PET was higher than that of the starting textile material and as that of the PET contained in the ribbon. The mass average molecular weight Mw was as expected lower than that of the starting textile material since the PET contained in the ribbon had already a lower Mw.

[0233] Short description of Figures Fig. 1 : shows the IR spectra of obtained POM solid and PET textile pieces in comparison to reference spectra of fresh POM and PET of Example 1.

[0234] Fig. 2 : shows the IR spectra of obtained PVC and PET textile pieces of Example 2 (PVC precipitated with iPrOH), each in comparison to a reference spectrum of fresh PVC and PET respectively.

[0235] Fig. 3 : shows the IR spectra of obtained PVC and PET textile pieces of Example 2 (PVC obtained after distillation), each in comparison to a reference spectrum of fresh PVC and PET respectively.

[0236] Cited Literature

[0237] “Dyes and Pigments” Metin Agikyildiz, Kubra Gunes, Ahmet Gurses Springer, 2016 (ISBN: 10 : 3319338900)

[0238] Industrial Organic Pigments - Klaus Hunger, Thomas Heber, Martin U. Schmidt, Friedrich Reisinger, Stefan Wanne Wiley-VCH, 4th edition, 2018 (ISBN: 978-3-527-32608-2) Chemistry and Technology of Natural and Synthetic Dyes and Pigments - Ashis Kumar Samanta, Nasser Awwad, IntechOpen, 2020 (ISBN: 9781789859980, 9781789859973, 9781839687587)

[0239] Encyclopedia of Color, Dyes, Pigments - Volume 1 , Gerhard Pfaff, de Gruyter, 2021 (ISBN: 311058588X)

[0240] Heinrich Zollinger: Color Chemistry: Syntheses, Properties, and Applications of Organic Dyes and Pigments. 3rd edition. WILEY-VCH Verlag, Weinheim 2003 (ISBN: 3-906390- 23-3)

[0241] Klaus Hunger (Ed.): Industrial Dyes: Chemistry, Properties, Applications. WILEY-VCH Verlag, Weinheim 2003 (ISBN: 3-662-01950-7)

[0242] Hermann Rath: Lehrbuch der Textilchemie. einschl. der textilchemischen Technologie. 2nd edition. Springer-Verlag, Berlin, Heidelberg 1963 (ISBN: 978-3-662-00065-6); Wilfried Kratzert, Rasmus Peichert

[0243] Farbstoffe. Quelle & Meyer, Heidelberg 1981 (ISBN: 3-494-01021-8)

[0244] Ullmann’s Encyclopedia of industrial chemistry, Wiley-VCH, 2000, sections “dyes and pigments” and “dyes, general survey” (ISBN: 9783527303854)

[0245] Dietrich Braun, Manfred Thallmaier, Journal of Polymer Science: Polymer Symposia, 16, 4, 1967, 2351-2364

Claims

Claims1 . A method for recovering polyester from an article, which comprises(i) a polyester;(ii) a part comprising a further polymer selected from polyacetal, polyvinyl chloride, and mixtures thereof; the method comprising:(a) providing the article and providing a solvent system comprising gamma valerolactone;(b) contacting the article with the solvent system at a temperature T1 of < 170 °C, thereby obtaining a solvent system, which is enriched in dissolved further polymer of (ii), and a residue of the article, which is depleted of said further polymer and comprises the polyester;(c) contacting the residue of the article obtained in (b) with a solvent system at a temperature T2 of > 170 °C, thereby obtaining a solvent system, which is enriched in dissolved polyester compared to the solvent system provided in (a);(d) precipitating the polyester from the solvent system, which is enriched in dissolved polyester, obtained in (c), thereby obtaining a precipitated polyester and a solvent system, which is depleted in dissolved polyester.

2. The method of claim 1 , wherein the part comprising a further polymer is / are closing and / or decoration means, preferably selected from the group consisting of zipper, ribbon, cramp, button, sequin, patch, hook, eyelet, grommet, buckle, clasp and mixtures of two or more thereof, preferably from the group consisting of zipper, button, sequin and mixtures of two or more thereof.

3. The method of claim 1 or 2, wherein neither between (a) and (b) nor between (b) and (c), nor -in the absence of (b)- between (a) and (c) a separation of part comprising a further polymer from the polyester (i) of the article is done (no pre-processing); and / or wherein neither between (a) and (b) nor -in the absence of (b)- between (a) and (c), a mechanical pre-treatment, preferably a shredding, is done.

4. The method of any one of claims 1 to 3, wherein the article further comprises(iii) one or more component(s) selected from the group consisting of a second polymer, a third polymer, a colorant and a filler, wherein second polymer and third polymer are different from each other and different from the polyester of (i) and from the further polymer of the parts comprising afurther polymer of (ii).

5. The method of any one of claims 1 to 4, wherein the article is a textile article or an article selected from the group consisting of a toying article, a sport equipment article, an outdoor equipment article or combined articles thereof.

6. The method of any one of claims 1 to 5, wherein at least 50 weight-%, preferably at least 60 weight-%, more preferably at least 70 weight-%, more preferably at least 80 weight-%, more preferably at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 99 weight-% of the solvent system consists of gamma-valerolactone, based on the total weight of the solvent system being 100 weight-%7. The method of any one of claims 1 to 6, wherein the polyester is based on 1 ,4-butanediol or 1 ,2-ethandiol, more preferably the polyester according to (i) is selected from the group consisting of a polymer based on 1 ,4-butanediol and terephthalic acid (polybutylene terephthalate, PBT), a polymer based on 1 ,2-ethanediol and terephthalic acid (polyethylene terephthalate, PET), a copolymer of 1 ,4-butanediol, adipic acid and terephthalic acid (poly- butylenadipat-terephthalat, PBAT), a polymer of 1 ,2-ethanediol and 2,5-furandicarboxylic acid (polyethylene furanoate, PEF) and mixtures of two or more of these (co)polymers, more preferably, the polyester comprises at least PET and / or PBT, more preferably the polyester is PET or PBT or a mixture of PET and PBT, more preferably the polyester comprises or is PET.

8. The method of any one of claims 4 to 7, wherein the second polymer is selected from the group consisting of polyurethane (Pll), polyethylene glycol (PEG), polytetrahydrofuran (pTHF), mixtures of these polymers and copolymers of these polymers, wherein the second polymer is more preferably Pll or a copolymer of Pll and PEG and / or pTHF, more preferably spandex; and / or wherein the third polymer is selected from polypropylene (PP), polyethylene (PE), polyamide (PA), natural polymer (such as cotton, viscose, linen) and mixtures of two or more thereof.

9. The method of any one of claims 4 to 8 comprising after (d)(y.1) separating the precipitated polyester obtained in (d) from the solvent system, which is depleted in dissolved polyester and comprises optionally the filler or a part of thefiller, thereby obtaining a precipitated polyester and the solvent system, which is depleted in dissolved polyester and which optionally comprises the filler or a part of the filler;(y.2) optionally washing the precipitated polyester obtained in (y.1);(y.3) drying the precipitated polyester obtained in (y.1) or the washed precipitated polyester obtained in (y.2), thereby obtaining a dried (washed) precipitated polyester.

10. The method of any one of claims 4 to 9 comprising after (d) or after (y.3), preferably after (y.3)(z) increasing the intrinsic viscosity of the precipitated polyester obtained in (d) or of the dried (washed) precipitated polyester obtained in (y.3).

11. Polyester obtained or obtainable from the process of any one of claims 1 to 10, preferably obtained or obtainable from step (d), (y.1), (y.2), (y.3) or (z), more preferably from step (y.3) or (z).

12. A The method according to any one of claims 1 to 10 comprising(I) providing polyester obtained from step (d), (y.1), (y.2), (y.3) or (z), preferably from step (y.3) or (z);(II) preparing a food packaging, a beverage packaging, a clothing, a foot wear, a wire, or a cable from the polyester provided in (I).

13. The method of any one of claim 1 to 12, wherein (b) comprises:(b.1) contacting the article with the solvent system at a temperature T1 of < 170 °C, thereby obtaining a solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer, and optionally in filler or part of the filler; and a residue of the article, which is depleted of said further polymer, optionally of colorant, optionally of second polymer and optionally of filler or part of the filler and comprises the polyester, optionally the metal containing part of (ii), optionally the filler or a part of the filler and optionally the third polymer;(b.2) separating the solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer and optionally in filler or part of the filler, obtained in (b.1) from the residue, preferably by a physical separation method, thereby obtaining a separated solvent system, which is enriched in dissolved further polymer of (ii), optionally in colorant, optionally in second polymer, and optionally in filler or part of the filler, compared to the solvent system provided in (a); and(b.3) separating at least the further polymer of (ii) and optionally the second polymer from the solvent system, thereby obtaining a separated fraction comprising the further polymer of (ii) and optionally the second polymer.

14. The method according to any one of claims 1 to 10, or 12 or 13, comprising the further step: converting the re-obtained polyester obtained by the process according to any one of claims 1 to 10, or 12 or 13 to obtain a polymer product.

15. The method according to any one of claims 1 to 10 or 12 or13 or 14, comprising the further step: converting a residue obtainable by or obtained by the process according to any one of claims 1 to 10, or 12 or 13 or 14, preferably obtained or obtainable from step (d), more preferably the residue comprising at least third polymer obtainable by or obtained by the process according to according to any one of claims 1 to 10, or 12 or 13 or 14, preferably obtained or obtainable from step (d), or the further polymer of (ii) and optionally the second polymer obtained in (b.3), to obtain one or more monomer, polymer or polymer product; wherein preferably, the monomer is a di- or polyol; preferably butandiol; aldehyde; preferably formaldehyde; di- or polyisocyanate; preferably methylene diphenyl diisocyanate (MDI), polymeric methylene diphenyl diisocyanate (pMDI), toluene diisocyanate (TDI), hexamethylenediisocyanate (HDI) or isophoronediisocyanate (IPDI); amide; preferably caprolactam; alkene; preferably styrene, ethene and norbornene; alkyne, (di)ester; preferably methyl methacrylate; mono or diacid; preferably adipic acid or terephthalic acid; diamine; preferably hexamethylenediamine, nonanediamine; or sulfones; preferably 4,4'-di- chlorodiphenyl sulfone; and / or wherein preferably the polymer is and / or the polymer product comprises polyamide (PA); preferably PA 6 or PA 66; polyisocyanate polyaddition product; preferably polyurethane (Pll), thermoplastic polyurethane (TPU), polyurea or polyisocyanurate (PIR); low-density polyethylene (LDPE), high-density polyethylene (HDPE), polyethylene (PE), polypropylene (PP), polyvinyl chloride (PVC), polyvinyl acetate (PVA), polystyrene (PS), poly acrylonitrile butadiene styrene (ABS), poly styrene acrylonitrile (SAN), poly acrylate styrene acrylonitrile (ASA), polytetrafluoroethylene (PTFE), poly(methyl acrylate) (PMA), poly(methyl methacrylate) (PMMA), polybutadiene (BR, PBD), poly(cis-1 ,4-isoprene), poly(trans-1 ,4- isoprene), polyoxymethylene (POM), polyethylene terephthalate (PET), polybutylene terephthalate (PBT), polybutylene adipate coterephthalate (PBAT), polyester (PES), polyether sulfone (PESLI), polyhydroxyalkanoate (PHA), poly-3-hydroxybutyrate (P3HB), poly-4-hydroxybutyrate (P4HB), polyhydroxyvalerate (PHV), polyhydroxyhexanoate (PHH), polyhydroxyoctanoate (PHO), polylactic acid (PLA), polysulfone (PSU), polyphenylene sulfone (PPSLI), polycarbonate (PC), polyether ether ketone (PEEK), poly(p-phenylene oxide) (PPO), poly(p-phenylene ether) (PPE); or copolymer or mixture thereof.

16. Method according to any one of claims 1 to 10, or 12 or 13 to 15, wherein the polymer and / or the polymer product is / are or is / are a part of: a part of a car; preferably cylinder head cover, engine cover, housing for charge air cooler, charge air cooler flap, intake pipe, intake manifold, connector, gear wheel, fan wheel, cooling water box, housing, housing part for heat exchanger, coolant cooler, charge air cooler, thermostat, water pump, radiator, fastening part, part of battery system for electromobility, dashboard, steering column switch, seat, headrest, center console, transmission component, door module, cover for car A, B, C or D pillar, spoiler, door handle, exterior mirror, windscreen wiper, windscreen wiper protection housing, decorative grill, cover strip, roof rail, window frame, sunroof frame, antenna panel, headlight and taillight, engine cover, cylinder head cover, intake manifold, airbag, cushion, or coating; a cloth; preferably shirt, trousers, pullover, boot, shoe, shoe sole, tight or jacket; an electrical part; preferably electrical or electronic passive or active component, circuit board, printed circuit board, housing component, foil, line, switch, plug, socket, distributor, relay, resistor, capacitor, inductor, bobbin, lamp, diode, LED, transistor, connector, regulator, integrated circuit (IC), processor, controller, memory, sensor, microswitch, microbutton, semiconductor, reflector housing for light-emitting diodes (LED), fastener for electrical or electronic component, spacer, bolt, strip, slide-in guide, screw, nut, film hinge, snap hook (snap-in), or spring tongue; a consumer, agricultural product or pharmaceutical product; preferably tennis string, climbing rope, bristle, brush, artificial grass, 3D printing filament, grass trimmer, zipper, hook and loop fastener, paper machine clothing, extrusion coating, fishing line, fishing net, offshore line and rope, vial, syringe, ampoule, bottle, sliding element, spindle nut, chain conveyor, plain bearing, roller, wheel, gear, roller, ring gear, screw and spring dampers, hose, pipeline, cable sheathing, socket, switch, cable tie, fan wheel, carpet, box or bottle for cosmetics, mattress, cushion, insulation, detergent, dishwasher tabs or powder, shampoo, body wash, shower gel, soap, fertilizer, fungicide, or pesticide; a packaging for the food industry; preferably mono- or multi-layer blown film, cast film (mono- or multi-layer), biaxially stretched film, or laminating film; or a part of a construction; preferably a rotor blade, insulating material, frame, housing, wall, coating, or separating wall.