Method for removing plasticizers from polymer materials

Abstract

A first aspect of the present invention relates to a method for removing a plasticizer from a polymeric material, the method comprising: (a) providing a polymeric material, the polymeric material comprising a polymer and a plasticizer, and providing a solvent comprising gamma-valerolactone; and (b) contacting the polymeric material with the solvent comprising gamma-valerolactone, thereby obtaining a liquid mixture comprising the solvent, dissolved polymer and dissolved plasticizer. In a second aspect, the invention relates to a polymer obtained or obtainable from the method according to the first aspect. A third aspect of the invention relates to a plasticizer obtained or obtainable by the method according to the first aspect. In a fourth aspect, the invention relates to the use of polymers obtained or obtainable by the method according to the first aspect for producing polymer products, and in a fifth aspect of the invention relates to the use of plasticizers obtained or obtainable by the method according to the first aspect for producing soft polymers. A sixth aspect of the invention relates to a method for further processing plasticizers comprising one or more post-treatment steps selected from the group consisting of hydrolysis, hydrogenation and transesterification.

Description

[0001] A first aspect of the present invention relates to a method for removing a plasticizer from a polymeric material, the method comprising: (a) providing a polymeric material that comprises a polymer and a plasticizer, and providing a solvent that comprises γ-valerolactone; and (b) contacting the polymeric material with the solvent that comprises γ-valerolactone to obtain a liquid mixture that comprises the solvent, dissolved polymer, and dissolved plasticizer. In a second aspect, the present invention relates to a polymer obtainable or obtained by the method according to the first aspect. A third aspect of the present invention relates to a plasticizer obtainable or obtained by the method according to the first aspect. In a fourth aspect, the present invention relates to the use of a polymer obtainable or obtained by the method according to the first aspect for the preparation of a polymeric product, wherein a fifth aspect of the present invention relates to the use of a plasticizer obtainable or obtained by the method according to the first aspect for the preparation of a flexible polymer. A sixth aspect of the present invention relates to a method for further processing a plasticizer, the method comprising one or more steps selected from the group consisting of hydrolysis, hydrogenation, and transesterification.

[0002] Synthetic polymers are generally used in two different forms, namely in a rigid form or in a flexible form (so-called soft form). Softening is usually achieved by adding a plasticizer to the polymer material, and the most widely used is phthalate. Considering the increasing use of polymer materials, considering the saving of raw materials and considering the reduction of plastic waste, there is also a need for recycling polymer materials. However, for recycling, it is also necessary to separate the polymer material from the incorporated plasticizer, especially considering the fact that several plasticizers are toxic or associated with other environmental or health-related problems, especially since sometimes the recycled polymer material is intended for different application fields - for example, the polymer used for window profiles will be reused for toys. Therefore, in most cases, recycling is only possible after extracting the plasticizer, and a mild method for separating the polymer material and the plasticizer would be highly desirable. "Mild" preferably means, firstly, using harmless chemicals, and secondly, the polymer and / or the plasticizer are recovered undamaged. However, so far, the methods known in the art use at least partially toxic fossil-based chemicals, and the methods for plasticizer extraction are complex and require complex solvent systems. For example, WO 01 / 70865A1 discloses a method for recycling plastic materials, where the plastic material can be a polar polymer such as a vinyl chloride polymer (PVC). The method includes dissolving the plastic material, where a solvent having a solubility parameter close to that of the plastic to be dissolved is used; only methyl ethyl ketone (MEK) is given as a suitable solvent. Water is used to precipitate the dissolved plastic material. In addition to being flammable and moderately explosive, MEK also has health-related problems because it can cause, for example, severe eye irritation. WO 02 / 14413A1 discloses a method for separating and recovering a target polymer and its additives from a material containing the polymer, where the target polymer and at least one additive are dissolved in a solvent, and the dissolved target polymer and additive are mixed with an anhydrous solvent II (precipitant) miscible with solvent I in such a way that the target polymer precipitates. Solvent I is selected from the group consisting of: low molecular weight alcohols (C1-C5), cyclic ethers (such as tetrahydrofuran), aliphatic ketones (such as acetone, methyl ethyl ketone), cyclic ketones (such as cyclohexanone), binary ester mixtures (such as DBE - a mixture of dimethyl esters of glutaric acid, succinic acid and adipic acid) and mixtures of these solvents, and solvent II is a low molecular weight alcohol (C1-C5). Additionally, here, the solvent used for dissolving the polymer is dangerous and associated with several health problems, such as those indicated above for MEK. US 4,071,479A relates to a method for recovering a reusable substantially pure vinyl chloride polymer resin from a polymer mixture, the method including dissolving the vinyl chloride polymer and then using a non-solvent, which is miscible with the solvent in substantially all proportions to precipitate the substantially pure vinyl chloride polymer resin.The solvents indicated for dissolving the polymer are methyl ethyl ketone, tetrahydrofuran, and dimethylformamide, and the anti-solvent can be selected from methanol, isopropyl alcohol, n-butanol, or an azeotrope of methyl ethyl ketone and methanol. Additionally, herein, the solvents used for dissolving the polymer are hazardous and are associated with several health issues, such as those indicated above for MEK.

[0003] Accordingly, an object of the present invention is to provide an improved method that enables the simple extraction of one or more plasticizers from a polymeric material while avoiding or at least reducing the use of harmful solvents, and enables the recovery of the polymer and / or plasticizer without damage.

[0004] First aspect - Method for removing plasticizer

[0005] In a first aspect, the problem is solved by providing a method for removing a plasticizer from a polymeric material, the method comprising:

[0006] (a) providing a polymeric material that comprises a polymer and a plasticizer, and providing a solvent that comprises γ-valerolactone;

[0007] (b) contacting the polymeric material with the solvent that comprises γ-valerolactone, thereby obtaining a liquid mixture that comprises the solvent, dissolved polymer, and dissolved plasticizer.

[0008] γ-Valerolactone (C5H8O2; IUPAC: 5-methyloxolan-2-one, abbreviation: GVL) is obtainable from carbohydrate-based biomass, for example, it is readily obtainable from sugars and is thus a "green" solvent. To date, it has been described at most as being able to dissolve polymeric materials. The GVL used in the context of the present invention is preferably a bio-renewable solvent (bio-renewable GVL), preferably a GVL that has been tested in accordance with ASTM standard D6866-16 as containing bio-based carbon. It has now surprisingly been found that, especially for polymeric materials that comprise one or more polymers as described below, especially for polymeric materials that comprise polyvinyl chloride (PVC, hereinafter TP.30), γ-valerolactone enables the removal of plasticizers from the polymeric material without having an adverse effect on the polymeric material, i.e., the obtained polymeric material (which is plasticizer-depleted compared to the polymeric material provided in (a)) has at least the same number-average molecular weight Mn and has a substantially the same weight-average molecular weight Mw as the polymeric material provided in (a). That is, the use of GVL enables the recovery of the polymer in an undamaged form. Additionally, it has surprisingly been found that GVL is excellent compared to other solvents with respect to the removal of plasticizers from polymeric materials, since it removes significantly more plasticizers from the polymeric material than other solvents.

[0009] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the method further comprises:

[0010] (c) precipitating the polymer from the mixture obtained in (b) by adding an anti-solvent, thereby obtaining a solid residue comprising the polymer and a liquid phase comprising the solvent, the anti-solvent, and the dissolved plasticizer.

[0011] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the polymer is preferably a thermoplastic polymer selected from the group consisting of

[0012] - a thermoplastic copolymer comprising at least two different monomers in polymerized form, the monomers being selected from the group consisting of: C2 to C 10 monoolefins (which are preferably selected from the group consisting of ethylene, propylene, 1,3-butadiene, 2-chloro-1,3-butadiene, and mixtures of two or more of these olefins), vinyl alcohol, C2 to C 10 - alkyl esters of vinyl alcohol, vinyl acetate, vinyl chloride, vinylidene chloride, vinylidene fluoride, tetrafluoroethylene, glycidyl acrylate, glycidyl methacrylate, acrylates of alcohol components having branched or unbranched C1 to C10 alcohols, methacrylates of alcohol components having branched or unbranched C1 to C10 alcohols, vinyl aromatic compounds (preferably styrene), (meth)acrylonitrile, ethylenically unsaturated monocarboxylic or dicarboxylic acids, and maleic anhydride (TP.1);

[0013] - polyvinyl esters (TP.2);

[0014] - polycarbonates (TP.3);

[0015] - polyethers (TP.4);

[0016] - polyether ketones (TP.5);

[0017] - thermoplastic polyurethanes (TP.6);

[0018] - polysulfides (TP.7);

[0019] - polysulfones (TP.8);

[0020] - polyesters (TP.9);

[0021] - polyalkylene terephthalates (TP.10);

[0022] - polyhydroxyalkanoates (TP.11);

[0023] - polybutylene succinate (TP.12);

[0024] - Poly(butylene succinate adipate) (TP.13);

[0025] - Polyacrylates with the same or different alcohol residues from the group of C4 to C8 alcohols, preferably selected from butanol, hexanol, octanol and 2 - ethylhexanol (TP.14);

[0026] - Polymethyl methacrylate (TP.15);

[0027] - Methyl methacrylate - butyl acrylate copolymer (TP.16);

[0028] - Acrylonitrile - butadiene - styrene copolymer (TP.17);

[0029] - Ethylene - propylene copolymer (TP.18);

[0030] - Ethylene - propylene - diene copolymer (TP.19);

[0031] - Polystyrene (TP.20);

[0032] - Styrene - acrylonitrile copolymer (TP.21);

[0033] - Acrylonitrile - styrene acrylate (TP.22);

[0034] - Styrene - butadiene - methyl methacrylate copolymer (TP.23);

[0035] - Styrene - maleic anhydride copolymer (TP.24);

[0036] - Styrene - methacrylic acid copolymer (TP.25);

[0037] - Polyoxymethylene (TP.26);

[0038] - Polyvinyl alcohol (TP.27);

[0039] - Polyvinyl acetate (TP.28);

[0040] - Polyvinyl butyral (TP.29);

[0041] - Polyvinyl chloride (TP.30);

[0042] - Polycaprolactone (TP.31);

[0043] - Polyhydroxybutyric acid (TP.32);

[0044] - Polyhydroxyvaleric acid (TP.33);

[0045] - Polylactic acid (TP.34);

[0046] - Ethyl cellulose (TP.35);

[0047] - Cellulose acetate (TP.36);

[0048] - Cellulose propionate (TP.37);

[0049] - Cellulose acetate / butyrate (TP.38)

[0050] and blends of two or more of these polymers.

[0051] In some preferred embodiments, polyethylene terephthalate (PET) is excluded from the list of polymers from TP.1 to TP.38. In some further preferred embodiments, the polymer is preferably a thermoplastic polymer selected from the group consisting of TP.1 to TP.9 and TP.11 to TP.38 and blends of two or more of these polymers. In some preferred embodiments, the polymer is preferably a thermoplastic polymer selected from the group consisting of TP.1 to TP.8 and TP.11 to TP.38 and blends of two or more of these polymers.

[0052] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the polymer is selected from the group consisting of: a copolymer that comprises vinyl chloride in polymeric form and at least one additional monomer selected from the group (TP.1.1) indicated for TP.1 in Example 3; polyvinyl acetate (TP.28); polyvinyl butyral (TP.29); polyvinyl chloride (TP.30); polycaprolactone (TP.31); and blends of two or more of these polymers.

[0053] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the polymer comprises polyvinyl chloride (TP.30), wherein preferably, based on the total weight of the polymer comprised in the polymeric material at 100 weight-%, at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 98 weight-% of the polymer comprised in the polymeric material is polyvinyl chloride.

[0054] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, at least 20 weight-% of the polymeric material consists of polymer, more preferably in the range of 20 to 90 weight-% of the polymeric material consists of polymer, the total weight of the polymeric material being 100 weight-%.

[0055] Generally speaking, polyvinyl chloride is obtained by homopolymerization of vinyl chloride. Polyvinyl chloride is prepared, for example, by (micro) suspension polymerization or bulk polymerization. The production of polyvinyl chloride by polymerization of vinyl chloride and the production and composition of plasticized polyvinyl chloride are described, for example, in "Becker / Braun, Kunststoff-Handbuch, Band 2 / 1: Polyvinylchlorid [Plastic Handbook, Volume 2, Part 1, Polyvinyl Chloride]", 2nd Edition, Carl Hanser Verlag [Carl Hanser Publishing House], Munich.

[0056] In some preferred embodiments, the polymeric material is a flexible PVC which preferably has a Shore stiffness in the range of 35 Shore A to 70 Shore D as determined according to DIN 53505:2000 - 08.

[0057] In some embodiments, the polymeric material contains a plasticizer distributed in the polymer, or in alternative embodiments, the polymer (preferably in powder form) is optionally dispersed in a liquid plasticizer (plasticized sol) together with pigments, fillers, and additives such as blowing agents. The plasticizer is not chemically bonded to the polymer but is embedded in the polymer or the polymer is dispersed in the (liquid) plasticizer.

[0058] In some preferred embodiments of the method for removing the plasticizer from the polymeric material, the solvent containing γ-valerolactone contains γ-valerolactone and optionally one or more solvents selected from the group consisting of water and organic solvents having a logK in the range of -1.6 to +1.6 OW and the one or more solvents are preferably selected from the group consisting of: water, C5 to C12 alkanes, aliphatic C1 to C10 alcohols, C3 to C10 ketones, C2 to C10 cyclohexanones, HO-[C1 to C10 alkyl - O-] n -H (where n is an integer in the range of 2 to 1000), C1 to C10 alkyl - O - C3 to C10 alkyl ethers, C3 to C10 cyclic ethers (optionally substituted by one or more C1 to C6 alkyl groups), C6 to C10 aromatic hydrocarbons (optionally substituted by one or more C1 to C6 alkyl groups), C2 to C10 aliphatic esters, C8 to C11 aromatic esters, C5 to C10 cyclic carboxylic esters (lactones), C3 to C12 amides, preferably R 1 R 2 N - C(=O) - R 3 (where R 1 、R 2 are independently C1 to C4 alkyl groups and R 3selected from the group consisting of C1-C9 alkyl, C1-C10 ester, and C1-C6 ether groups), C3-C6 lactams (optionally substituted by one or more substituents selected from C1-C6 alkyl, C1-C6 ester, and C1-C6 ether groups), and C5 imidazolidines (optionally substituted by one or more C1-C6 alkyl groups), C5-C7 imidazolidinones (optionally substituted by one or more C1-C6 alkyl groups).

[0059] Preferably, based on the total weight of 100 weight-% of the solvent, at least 1 weight-%, more preferably at least 5 weight-%, more preferably at least 10 weight-%, more preferably at least 20 weight-%, more preferably at least 30 weight-%, more preferably at least 40 weight-%, 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 95 weight-%, more preferably at least 96 weight-%, more preferably at least 97 weight-%, more preferably at least 98 weight-%, more preferably at least 99 weight-% of the solvent consists of γ-valerolactone.

[0060] Suitable solvents and the decimal logarithm of the octanol-water partition coefficient (log K OW ) are known to the person skilled in the art. The octanol-water partition coefficient K OW of a given compound is defined as the ratio of the chemical concentration of the compound in the octanol phase to the chemical concentration of the compound in the aqueous phase in a two-phase system of 1-octanol and water at a temperature of 25 °C (298 K). The method for determining the octanol-water partition coefficient K OW of a given compound is known to the person skilled in the art. For example, the octanol-water partition coefficient K OW of a given compound is determined using the shake-flask method, which involves dissolving the compound in a certain volume of high-purity 1-octanol and deionized water (previously mixed and calibrated for at least 24 h) and measuring the concentration of the compound in each octanol phase and aqueous phase by a method precise enough, preferably via UV / VIS spectroscopy. This method is described in OECD Test Guideline No. 107 adopted on July 27, 1995. The K OW values of various substances are known and can be easily found, for example, in the Dortmund (DDB, accessible at http: / / www.ddbst.com / ddb-search) database.

[0061] Regarding suitable solvents, for example, aliphatic C1 to C10 alcohols are preferably C1 to C6 monohydric alcohols, more preferably one or more selected from the group consisting of methanol, ethanol, and butanol. C3 to C10 ketones are preferably acetone or methyl ethyl ketone or a mixture of acetone and methyl ethyl ketone. C2 to C10 cyclo ketones are preferably cyclohexanone. C3 to C10 cyclic ethers optionally substituted with one or more C1 to C3 alkyl groups are preferably tetrahydrofuran or 2-methyltetrahydrofuran or a mixture of tetrahydrofuran and 2-methyltetrahydrofuran. C6 to C10 aromatic hydrocarbons optionally substituted with one or more C1 to C3 alkyl groups are preferably one or more selected from the group consisting of benzene, toluene, ethylbenzene, xylene (ortho or para), and mesitylene. C1 to C10 esters are preferably one or more selected from the group consisting of esters of C1 to C6 aliphatic monohydric alcohols and C2 to C5 aliphatic acids. C5 to C10 cyclic carboxylic acid esters (lactones) are preferably one or more selected from the group consisting of δ-valerolactone, methylated γ-butyrolactone, ethylated γ-butyrolactone, propylated γ-butyrolactone, and β-propiolactone. C3 to C6 lactams optionally substituted with one or more C1 to C3 alkyl groups are preferably selected from the group consisting of 2-pyrrolidone, 3-pyrrolidone, and mixtures thereof, each optionally substituted with one or more C1 to C3 alkyl groups preferably at the nitrogen atom, more preferably N-methyl-2-pyrrolidone. Imidazolidinones optionally substituted with one or more C1 to C3 alkyl groups are preferably 1,3-dimethyl-2-imidazolidinone.

[0062] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the plasticizer is selected from the group consisting of

[0063] - Dialkyl cyclohexane-1,2-dicarboxylates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups;

[0064] - Dialkyl cyclohexane-1,3-dicarboxylates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups;

[0065] - Dialkyl cyclohexane-1,4-dicarboxylates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups;

[0066] - Dialkyl phthalates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups;

[0067] - Alkyl aryl phthalates, wherein the alkyl group is selected from C4-C13 alkyl groups and the aryl group is selected from benzyl and phenyl;

[0068] - Dialkyl terephthalates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups;

[0069] - Trialkyl trimellitates;

[0070] - Alkyl benzoates;

[0071] - Dibenzoates of diols;

[0072] - Pentaerythritol esters;

[0073] - Alkyl esters of saturated monocarboxylic acids;

[0074] - Esters of unsaturated monocarboxylic acids;

[0075] - Diesters of saturated dicarboxylic acids;

[0076] - Diesters of unsaturated dicarboxylic acids;

[0077] - Aromatic sulfonic acid esters;

[0078] - Alkyl sulfonic acid esters;

[0079] - Glycerol esters;

[0080] - Isosorbide esters;

[0081] - Phosphate esters;

[0082] - Tricitrate esters;

[0083] - Acetylated tricitrate esters;

[0084] - Alkyl pyrrolidone derivatives;

[0085] - Dialkyl 2,5-furandicarboxylates;

[0086] - Dialkyl 2,5-tetrahydrofurandicarboxylates;

[0087] - Polyesters of aliphatic and / or aromatic polycarboxylic acids and at least dihydric alcohols;

[0088] - Epoxidized vegetable oils;

[0089] - Epoxidized fatty acid monoalkyl esters;

[0090] And mixtures of two or more thereof.

[0091] The dialkyl cyclohexane-1,2-dicarboxylates have C atoms in the range of 4 to 14 in the alkyl chain. The alkyl chains of the dialkyl cyclohexane-1,2-dicarboxylates independently of one another have the same or different numbers of C atoms. The dialkyl cyclohexane-1,2-dicarboxylates are preferably selected from the group consisting of: bis-(2-ethylhexyl)-1,2-cyclohexanedicarboxylate, bis-(isononyl)-1,2-cyclohexanedicarboxylate, or bis-(2-propylheptyl)-1,2-cyclohexanedicarboxylate and mixtures of two or more thereof. The dialkyl cyclohexane-1,3-dicarboxylates have C atoms in the range of 4 to 14 in the alkyl chain. The alkyl chains of the dialkyl cyclohexane-1,3-dicarboxylates independently of one another have the same or different numbers of C atoms. The dialkyl cyclohexane-1,4-dicarboxylates have 4 to 13 C atoms in the alkyl chain. The alkyl chains of the dialkyl cyclohexane-1,4-dicarboxylates independently of one another have the same or different numbers of C atoms. The dialkyl cyclohexane-1,4-dicarboxylates are preferably selected from the group consisting of: bis-(2-ethylhexyl) cyclohexane-1,4-dicarboxylate, bis-(isononyl)-1,4-cyclohexanedicarboxylate, or bis-(2-propylheptyl)-1,4-cyclohexanedicarboxylate and mixtures of two or more thereof. The dialkyl phthalates have 4 to 13 C atoms in the alkyl chain. The alkyl chains independently of one another have the same or different numbers of C atoms. The dialkyl phthalate can be diisononyl phthalate. The dialkyl terephthalates have 4 to 13 C atoms in the alkyl chain. The alkyl chains independently of one another have the same or different numbers of C atoms. The trialkyl trimellitates have 4 to 13 C atoms in the alkyl chain. The alkyl chains of the trialkyl trimellitates independently of one another have the same or different numbers of C atoms. The alkyl benzoates have 7 to 13 C atoms in the alkyl chain.

[0092] The alkyl benzoates are preferably selected from the group consisting of isononyl benzoate, isodecyl benzoate, 2-propylheptyl benzoate, and mixtures of two or more thereof. The dibenzoates are preferably selected from the group consisting of diethylene glycol dibenzoate, dipropylene glycol dibenzoate, tripropylene glycol dibenzoate, dibutylene glycol dibenzoate, and mixtures of two or more thereof. The saturated monocarboxylic acid esters are preferably selected from the group consisting of esters of acetic acid, butyric acid, valeric acid, lactic acid, and mixtures of two or more thereof. In an alternative embodiment, the saturated monocarboxylic acid esters are preferably selected from the group consisting of esters of monocarboxylic acids and polyols. For example, valeric acid can be esterified with pentaerythritol. The unsaturated monocarboxylic acid esters are preferably esters of acrylic acid. The unsaturated dicarboxylic acid diesters are preferably esters of maleic acid. The alkyl sulfonates have 8 to 22 C atoms in the alkyl chain. The alkyl sulfonates are preferably phenyl or tolyl esters of pentadecylsulfonic acid. The isosorbide esters are generally diisosorbide esters esterified with C8 to C13 carboxylic acids. The diisosorbide esters have different or identical C8 to C13 alkyl chains. The phosphate esters are preferably selected from the group consisting of tris-2-ethylhexyl phosphate, trioctyl phosphate, triphenyl phosphate, isodecyl diphenyl phosphate, bis-2(2-ethylhexyl)phenyl phosphate, 2-ethylhexyl diphenyl phosphate, and mixtures of two or more thereof. In the case of the citrate esters, the OH groups are free or in carboxylated form, such as in acetylated form. The alkyl chains of the citrate esters or acetylated citrate esters independently contain 4 to 8 C atoms. The alkyl pyrrolidone derivatives have 4 to 18 C atoms in the alkyl chain. The dialkyl 2,5-furandicarboxylates have 5 to 13 C atoms in the alkyl chain. The alkyl chains of the dialkyl 2,5-furandicarboxylates independently have different numbers of C atoms. The dialkyl 2,5-tetrahydrofurandicarboxylates have 5 to 13 C atoms in the alkyl chain. The alkyl chains of the dialkyl 2,5-tetrahydrofurandicarboxylates independently have different numbers of C atoms. The polyesters with aromatic or aliphatic polycarboxylic acids are preferably polyesters based on adipic acid and polyols, such as dialkylene glycol adipates having 2 to 6 C atoms in the alkylene units. Examples can include polyester adipates, polyglycol adipates, and polyester phthalates.

[0093] In some preferred embodiments of the method for removing plasticizers from polymeric materials, the plasticizer at least comprises a cyclohexane-1,2-dicarboxylic acid dialkyl ester of formula (I)

[0094]

[0095] , wherein R 1 and R 2Independently selected from the group consisting of branched C4 to C13 alkyl and straight-chain C1 to C13 alkyl, preferably selected from the group consisting of branched C7 to C11 alkyl and straight-chain C7 to C11 alkyl, more preferably R 1 and R 2 are each independently a branched or straight-chain C9 alkyl residue, and more preferably the plasticizer comprises at least diisononyl cyclohexane-1,2-dicarboxylate (DINCH).

[0096] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the polymeric material comprises an amount of plasticizer in the range of 20 phr to 490 phr. "phr" means "parts per 100 parts" and indicates the amount of plasticizer per 100 parts of polymeric material.

[0097] In some specific embodiments, the polymer comprised in the polymeric material provided in (a) comprises at least polyvinyl chloride (TP.30), and the plasticizer comprised in the polymeric material provided in (a) comprises at least DINCH. In these specific embodiments, the method for removing a plasticizer from a polymeric material comprises:

[0098] (a) providing a polymeric material which comprises at least polyvinyl chloride (TP.30) as the polymer and a plasticizer which comprises at least DINCH, and providing a solvent comprising γ-valerolactone;

[0099] (b) contacting the polymeric material with the solvent comprising γ-valerolactone so as to obtain a liquid mixture which comprises the solvent, dissolved polyvinyl chloride and dissolved DINCH.

[0100] Preferably, based on the total weight of the polymer comprised in the polymeric material provided in (a) of 100 weight-%, at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 98 weight-% of the polymer comprised in the polymeric material provided in (a) is polyvinyl chloride, and the polymeric material comprises an amount of plasticizer in the range of 20 to 490 phr, preferably at least DINCH, wherein more preferably at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 98 weight-% of the plasticizer comprised in the polymeric material provided in (a) is DINCH, and the total amount of plasticizer comprised in the polymeric material is 100 weight-%.

[0101] In addition to the plasticizer, the polymeric material may further contain additional additives, preferably additives selected from the group consisting of: stabilizers, slip agents, fillers, colorants (dyes and / or optical brighteners and / or pigments), flame retardants, light stabilizers, blowing agents, polymer processing aids, impact modifiers, antistatic agents, biostabilizers, or mixtures of two or more thereof. Stabilizers are conventional polyvinyl chloride stabilizers in solid and liquid form, preferably selected from the group consisting of: Ca / Zn, Ba / Zn, Pb, Sn stabilizers, acid-binding layered silicates, carbonates (preferably hydrotalcite), and mixtures of two or more thereof. Based on the total weight of the polymeric material of 100 weight-%, the polymeric material preferably contains a stabilizer content in the range of 0.05 to 7 weight-%. Preferably, the content of the stabilizer is in the range of 0.1 to 5 weight-%, more preferably in the range of 0.5 to 3 weight-%. Lubricants are generally used to reduce the adhesion between the disclosed molding composition or the disclosed plastisol and the surface, and are intended to reduce, for example, the frictional force during mixing, plasticization, or molding. All common lubricants used in plastic processing can be used as lubricants in the polymeric material. Commonly used lubricants in plastic processing are, for example, hydrocarbons (such as oils, kerosene, PE waxes, or mixtures thereof), fatty alcohols containing 6 to 20 carbon atoms, ketones, carboxylic acids (such as fatty acids, montanic acids, or mixtures thereof), oxidized PE waxes, metal salts of carboxylic acids, carboxylic acid amides, carboxylic acid esters (produced by the esterification of alcohols such as ethanol, fatty alcohols, glycerol, ethylene glycol, or pentaerythritol with long-chain carboxylic acids). Based on the total weight of the polymeric material of 100 weight-%, the polymeric material preferably contains a lubricant content in the range of 0.01 to 10 weight-%. Preferably, the lubricant content is in the range of 0.05 to 5 weight-%, more preferably in the range of 0.2 to 2 weight-%. Fillers are generally used to positively affect the compressive strength, tensile strength, and / or flexural strength, stiffness, and / or heat distortion temperature of the polymeric material. For example, carbon black and / or inorganic fillers are preferably present as fillers in the disclosed polymeric material. Inorganic fillers are preferably selected from the group consisting of: natural calcium carbonate (such as chalk, limestone, marble), synthetic calcium carbonate, dolomite, silicates, silica, sand, diatomaceous earth, aluminosilicates (such as kaolin, mica, feldspar), and any mixture of two or more of the previously mentioned fillers. Based on the total weight of the molding compound or plastisol, the polymeric material preferably contains a filler content in the range of 0.01 to 80 weight-%. Preferably, the content of the filler is in the range of 0.01 to 60 weight-%, more preferably 1 to 40 weight-%. Thus, the disclosed polymeric material preferably contains a filler content in the range of 2, 5, 8, 10, 12, 15, 18, 20, 22, 25, 27, 30, 33, 36, or 39 weight-%. Colorants can be used to adapt the disclosed molding composition or the disclosed plastisol to different applications. Colorants can be, for example, pigments or dyes.The pigment can be, for example, an inorganic and / or organic pigment contained in the polymeric material. The inorganic pigment can be a cobalt pigment such as CoO / Al2O3 and / or a chromium pigment such as Cr2O3. The organic pigment can be a monoazo pigment, a condensed azo pigment, a azomethine pigment, an anthraquinone pigment, quinacridone, a phthalocyanine pigment, and / or a dioxazine pigment. Based on the total weight of 100 weight-% of the polymeric material, the disclosed molding composition or the disclosed plastisol preferably contains a colorant content in the range of 0.01 to 10 weight-%. Preferably, the colorant content is in the range of 0.05 to 5 weight-%, more preferably 0.1 to 3 weight-%. A flame retardant can be used to reduce the flammability of the disclosed molding compound or the disclosed plastisol and to reduce the smoke formation during combustion. The flame retardant preferably present in the disclosed polymeric material is preferably selected from the group consisting of antimony trioxide, chlorinated kerosene, phosphate esters, aluminum hydroxide, boron compounds, and mixtures of two or more of these compounds. Based on the total weight of 100 weight-% of the polymeric material, the polymeric material preferably contains a flame retardant content in the range of 0.01 to 10 weight-%. Preferably, the flame retardant content is in the range of 0.2 to 5 weight-%, more preferably in the range of 0.5 to 2 weight-%. A light stabilizer (such as a UV absorber) can be used to protect the disclosed molding composition or the disclosed plastisol from damage caused by the influence of light. The light stabilizer is preferably selected from the group consisting of hydroxybenzophenone, hydroxyphenylbenzotriazole, cyanoacrylate, hindered amine light stabilizers (such as derivatives of 2,2,6,6-tetramethylpiperidine), and mixtures of two or more of these compounds. Based on the total weight of 100 weight-% of the polymeric material, the polymeric material preferably contains a light stabilizer content in the range of 0.01 to 7 weight-%. Preferably, the light stabilizer content is in the range of 0.02 to 4 weight-%, more preferably in the range of 0.05 to 3 weight-%.

[0102] Contact

[0103] In some preferred embodiments of the method for removing the plasticizer from the polymeric material, contacting the polymeric material with the solvent containing γ-valerolactone in (b) is carried out at a temperature T1 below 190 °C, preferably below 180 °C, more preferably below 170 °C, more preferably at a temperature T1 in the range of 90 °C to <170 °C, more preferably in the range of 95 °C to 165 °C, more preferably in the range of 100 °C to 150 °C.

[0104] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, in (b) the polymeric material is contacted with the solvent comprising γ-valerolactone for a period of at least 0.1 h, preferably for a period in the range of 0.1 to 10 h, preferably for a period in the range of 0.1 to 6 h, more preferably for a period in the range of 0.1 to 4 h. In some preferred embodiments of the method for removing a plasticizer from a polymeric material, in (b) the contacting of the polymeric material with the solvent comprising γ-valerolactone is carried out at a pressure in the range of 800 to 200,000 hPa. In some preferred embodiments of the method for removing a plasticizer from a polymeric material, in (b) the contacting of the polymeric material with the solvent comprising γ-valerolactone is carried out at a polymer material: solvent ratio by mass in the range of 1:1 to 1:100, more preferably in the range of 1:1 to 1:20, more preferably in the range of 1:1 to 1:10.

[0105] "Contacting" preferably means that the polymer is at least partially immersed in the solvent. Preferably, the polymer is at least partially immersed in the solvent because 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 polymer is in contact with the solvent, based on the total surface of the 100% polymeric material.

[0106] Anti-solvent

[0107] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, step (c) comprises:

[0108] (c.1) adjusting the temperature to a temperature T2 below T1, preferably a temperature in the range of 10 °C to 100 °C, preferably a temperature in the range of 15 °C to 90 °C, more preferably a temperature in the range of 20 °C to 80 °C;

[0109] (c.2) precipitating the polymer from the mixture obtained in (b) by adding an anti-solvent at T2;

[0110] Thereby obtaining a solid residue comprising the polymer and a liquid phase comprising the solvent, the anti-solvent and the dissolved plasticizer.

[0111] According to Ullmann's Encyclopedia of Industrial Chemistry (Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, 2012, Vol. 33, Chapter "Solvents", pp. 619 - 688, especially p. 626; DOI: 10.1002 / 14356007.a24_437), a solvent is defined as a substance that can dissolve a given substance such as a polymer (solute) at room temperature; the solubility parameters of the solvent and the solute are similar. A non-solvent (also known as an anti-solvent) is defined as a substance that cannot dissolve the substance under discussion. The solubility parameter and hydrogen bond parameter of the anti-solvent are outside the solubility region of the polymer but within the solubility region of the substance to be dissolved, especially within the solubility region of the plasticizer.

[0112] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the anti-solvent used in step (c) or (c.2) is selected from the group consisting of water, C1 - C5 monohydric alcohols, C1 - C6 dihydric alcohols, and mixtures of two or more of these solvents, preferably selected from the group consisting of water, C1 - C5 monohydric alcohols, C1 - C5 dihydric alcohols, and mixtures of two or more of these solvents, more preferably selected from the group consisting of water, C1 - C3 monohydric alcohols, and mixtures of two or more of these solvents, more preferably the anti-solvent used in step (c) or (c.2) contains isopropyl alcohol, and more preferably at least 95 weight-% of the anti-solvent used in step (c) or (c.2) consists of isopropyl alcohol. As GVL, the isopropyl alcohol used is preferably a bio-renewable solvent (bio-renewable isopropyl alcohol), i.e., obtained from carbohydrate-based biomass and thus a "green" solvent. Bio-renewable solvents are derived from renewable and sustainable bio-based materials, thus significantly reducing their environmental impact. Bio-renewable solvents are preferably tested to contain bio-based carbon according to ASTM standard D6866 - 16.

[0113] In some specific embodiments, the polymer contained in the polymeric material provided in (a) contains at least polyvinyl chloride (TP.30), and the plasticizer contained in the polymeric material provided in (a) contains at least DINCH, and further, the anti-solvent used in step (c) or (c.2) contains at least isopropyl alcohol. In these specific embodiments, the method for removing a plasticizer from a polymeric material comprises:

[0114] (a) providing a polymeric material that contains at least polyvinyl chloride (TP.30) as the polymer and a plasticizer that contains at least DINCH, and providing a solvent that contains γ-valerolactone;

[0115] (b) contacting the polymeric material with a solvent comprising γ-valerolactone to obtain a liquid mixture comprising the solvent, dissolved polyvinyl chloride, and dissolved DINCH; and

[0116] (c) precipitating at least the polyvinyl chloride from the mixture obtained in (b) by adding an anti-solvent, the anti-solvent comprising isopropanol; or (instead of only (c))

[0117] (c.1) adjusting the temperature to a temperature T2 below T1, preferably a temperature in the range of 10 °C to 100 °C, preferably a temperature in the range of 15 °C to 90 °C, more preferably a temperature in the range of 20 °C to 80 °C; and

[0118] (c.2) precipitating the polyvinyl chloride from the mixture obtained in (b) at T2 by adding an anti-solvent, the anti-solvent comprising isopropanol, preferably bio-renewable isopropanol;

[0119] to obtain a solid residue comprising polyvinyl chloride and a liquid phase comprising the solvent, (bio-renewable) isopropanol, and dissolved DINCH.

[0120] In these specific embodiments, based on the total weight of the polymer in the polymeric material provided in (a) at 100 weight-%, at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 98 weight-% of the polymer in the polymeric material provided in (a) is polyvinyl chloride, and the polymeric material comprises an amount of plasticizer in the range of 20 to 490 phr, preferably at least DINCH, wherein more preferably at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 98 weight-% of the plasticizer in the polymeric material provided in (a) is DINCH, the total amount of plasticizer comprised in the polymeric material is 100 weight-%, and preferably at least 95 weight-% of the anti-solvent used in step (c) or (c.2) consists of isopropanol.

[0121] Preferably, the anti-solvent is added in step (c) or (c.2) at a weight-based anti-solvent:polymeric material ratio in the range of 4:1 to 75:1, more preferably in the range of 5:1 to 50:1, more preferably in the range of 5:1 to 10:1. The weight of the polymeric material is the weight of the polymeric material comprising the polymer and plasticizer initially provided in (a).

[0122] The amount of residual plasticizer

[0123] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the polymer of the solid residue obtained in (c) or (c.2) comprises < 5%, preferably < 1%, of the amount of plasticizer already present in the polymeric material provided in (a).

[0124] Post-treatment step

[0125] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the method further comprises:

[0126] (d) separating the solid residue comprising the polymer obtained in (c) or (c.2) from the liquid phase comprising the solvent, the anti-solvent and the dissolved plasticizer, thereby obtaining the solid residue comprising the polymer and the liquid phase comprising the solvent, the anti-solvent and the dissolved plasticizer;

[0127] (e) optionally washing the solid residue obtained in (d) with an anti-solvent;

[0128] (f) drying the solid residue obtained in (d) or the washed solid residue obtained in (e).

[0129] The separation in (d) is carried out by methods and means known to the person skilled in the art, in particular solid-liquid separation methods such as filtration, for example, hot pressure filtration, sedimentation or centrifugation (see Handbuch der mechanischen Fest-Flüssig-Trennung Taschenbuch [Handbook of Mechanical Solid-Liquid Separation] - 29 April 2004 by Klaus Luckert (editor)).

[0130] In some preferred embodiments of the method for removing a plasticizer from a polymeric material, the method comprises one or more post-treatment steps, wherein the one or more post-treatment steps preferably comprise

[0131] (g) separating the solvent and the anti-solvent by distillation and / or separating the solvent from the dissolved plasticizer by distillation, thereby obtaining a liquid fraction preferably comprising the plasticizer and one or more liquid fractions comprising the solvent and / or the anti-solvent.

[0132] The plasticizer obtained in (g) is preferably in liquid form. However, due to the higher molar mass of the plasticizer compared to the solvent and the anti-solvent and the resulting higher boiling point temperature, the plasticizer is not removed in the distillation.

[0133] In some preferred embodiments of the method for removing plasticizer from a polymeric material, the method further comprises at least partially recycling the separated solvent obtained in (g) to (b) and / or at least partially recycling the separated anti-solvent obtained in (g) to (c).

[0134] Second aspect - Polymer obtainable or obtained by the method

[0135] In a second aspect, the invention relates to a polymer obtainable or obtained by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect. All the details, embodiments and preferred embodiments described in the part related to the first aspect above also apply to the second aspect.

[0136] Third aspect – Plasticizer obtainable or obtained by the method

[0137] In a third aspect, the invention relates to a plasticizer obtainable or obtained by the method according to the first aspect, preferably by (g). All the details, embodiments and preferred embodiments described in the part related to the first aspect above also apply to the third aspect.

[0138] Fourth aspect - Use of the polymer

[0139] According to a fourth aspect, the invention relates to the use of a polymer obtainable or obtained by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect, for the preparation of a polymeric product, preferably a soft polymeric product comprising at least one plasticizer, wherein the at least one plasticizer is preferably REACH-approved. All the details, embodiments and preferred embodiments described in the part related to the first aspect above also apply to the fourth aspect.

[0140] A REACH-approved plasticizer means a plasticizer registered in accordance with Regulation (EC) No. 1907 / 2006 "Registration, Evaluation, Authorization and Restriction of Chemicals (REACH)" and not listed in Annex XVII of the Regulation.

[0141] In some preferred embodiments, as indicated above, the polymer obtainable or obtained by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect, is used for the preparation of a soft polymeric product.

[0142] In one aspect of the said preferred embodiment, the invention also relates to a method for preparing a product, the method comprising

[0143] (I) Provide a polymer obtained as by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect;

[0144] (II) Prepare a polymer product, preferably a soft polymer product, from the polymer provided in (I) by adding at least one plasticizer, wherein the at least one plasticizer is preferably REACH-approved.

[0145] In some alternative preferred embodiments, a polymer obtained or obtainable by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect, is used to prepare a rigid polymer product without adding one or more plasticizers.

[0146] In one aspect of the said alternative preferred embodiment, the invention also relates to a method for preparing a rigid polymer product, the method comprising

[0147] (I) Provide a polymer obtained as by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect;

[0148] (II) Prepare a rigid polymer product from the polymer provided in (I), the preparation preferably being carried out by molding,

[0149] wherein no plasticizer is added in both (I) and (II).

[0150] "No plasticizer added" and "no plasticizer added in both (I) and (II)" mean that even if there is a certain amount of plasticizer, the amount is too low to affect the rigid properties of the rigid polymer product.

[0151] The obtained rigid polymer product, i.e., a rigid polymer material made of a polymer obtained or obtainable by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect, is used for, for example, producing sheets, tubes, pipes, profiles, blisters, records, windows, window profiles, traffic management parts, floor coverings or thermoformed sheets.

[0152] Fifth aspect - Use of the plasticizer

[0153] According to a fifth aspect, the invention relates to the use of a plasticizer obtained or obtainable by the method according to the first aspect, preferably by (g) of the method according to the first aspect, optionally after one or more post-treatment steps, for the preparation of a flexible polymer. All details, examples and preferred examples described above in the part related to the first aspect also apply to the fifth aspect. This also applies to the REACH-based definitions given above in the part related to the fourth aspect of the invention.

[0154] In some preferred embodiments, the invention also relates to a method for preparing a flexible polymer product, the method comprising

[0155] (I) providing a plasticizer obtained or obtainable by the method according to the first aspect, preferably by (g) of the method according to the first aspect, and a polymer;

[0156] (II) preparing a flexible polymer material from the polymer and the plasticizer provided in (I).

[0157] Preferably, the polymer provided in (I) is a (fresh or recycled) polymer as defined as TP.1 to TP.38 in the part related to the first aspect.

[0158] The flexible polymer material obtained as described in the parts related to the fourth and fifth aspects contains a plasticizer which, in some embodiments, is distributed in the polymer, or in alternative embodiments, the polymer (preferably in powdered form) is optionally dispersed in a liquid plasticizer (plasticized sol) together with pigments, fillers and additives (such as blowing agents). The plasticizer is not chemically bonded to the polymer but is embedded in the polymer or the polymer is dispersed in the (liquid) plasticizer.

[0159] The obtained flexible polymer material, i.e., the flexible polymer material made from the polymer obtained or obtainable by the method according to the first aspect, preferably by (e) and / or (f) of the method according to the first aspect, or the flexible polymer material made from the plasticizer obtained or obtainable by the method according to the first aspect, preferably by (g) of the method according to the first aspect, is used, for example, for the production of molded bodies, gloves, films, wallpapers, or heterogeneous flooring, or for textile coating.

[0160] The molded articles are, for example, containers, devices or foaming devices. The containers are, for example, the housings of electrical appliances (such as kitchen appliances) or computer housings, pipes, hoses such as water or irrigation hoses, industrial rubber hoses, chemical hoses, sheaths for electrical wires or cables, sheaths for tools, bicycle, scooter or trolley handles, metal coatings, or packaging containers. The devices are, for example, tools, furniture such as chairs, shelves, tables, record discs, profiles such as window profiles, ground profiles for outdoor use or profiles for conveyor belts, parts for vehicle construction such as body parts, chassis protection devices or shock absorbers, or dampers. The foaming devices are, for example, cushions, mattresses, foams or insulating materials. The films are, for example, tarpaulins such as truck tarpaulins, roof tarpaulins, geomembrane tarpaulins, stadium roofs or tent tarpaulins, gaskets, laminated films such as films for laminated safety glass, self-adhesive films, laminated films, shrink films, outdoor floor coverings, tape films, coatings, swimming pool films, ornamental pool films, tablecloths or artificial leathers. The molding compound is used for producing molded articles or films that come into direct contact with humans or food. The molded articles or films that come into direct contact with humans or food are, for example, medical products, hygiene products, food packaging, indoor products, baby and children's products, baby care products, sports or leisure products, clothing, fibers or fabrics. The medical products made using the molding compound are, for example, enteral feeding tubes or hemodialysis tubes, ventilation tubes, drainage tubes, infusion tubes, infusion bags, blood bags, catheters, tracheal intubation tubes, disposable syringes, gloves or breathing masks. The food packaging products made using the molding compound are, for example, food wrap, food pipes, drinking water pipes, food storage or freezing containers, lid seals, caps, bottle caps or artificial wine corks. The indoor products made using the molding compound are, for example, floor coverings, which are uniform or composed of multiple layers including at least one foam layer, such as floor coverings, mudguard mats, sports floors, luxury vinyl tiles (LVT), artificial leathers, wall coverings, foam or non-foam wallpapers in buildings, interior trims or console coverings in vehicles. The baby and children's products made using the molding compound are, for example, toys such as dolls, play figures or modeling clay, inflatable toys such as balls or rings, non-slip socks, swimming aids, stroller coverings, diaper changing pads, thermos flasks, teething rings or bottles. The sports or leisure products made using the molding compound are, for example, sports balls, sports mats, seat cushions, massage balls or rollers, shoes, soles, balls, air cushions, protective glasses, gloves or water bottles. The clothing made using the molding compound is, for example, latex clothing, protective clothing, rain jackets or rubber boots.

[0161] In a preferred embodiment, in the case where the obtained soft polymer material is a plastisol, the plastisol is generally used as follows:

[0162] Plasticized sols are usually shaped into the shape of a finished product by different processes, such as coating, casting (such as shell casting or rotational molding), dipping, printing (such as screen printing), spraying, etc. Subsequently, gelling is carried out by heating, and after cooling, a homogeneous and somewhat flexible product is obtained. Plasticized sols are used for the production of films, wallpapers, seamless hollow bodies, gloves, heterogeneous floors or for applications in the textile industry such as textile coatings. Films are, for example, truck tarpaulins, roof tarpaulins, general covers such as marine covers, pram covers or stadium roofs, tent tarpaulins, geomembranes, tablecloths, coatings, swimming pool films, artificial leathers or ornamental pond films. Gloves are, for example, gardening gloves, medical gloves, chemical protective gloves, protective gloves or disposable gloves. In addition, plasticized sols are used for manufacturing, for example, gaskets, lid seals, interior trim or console covers in vehicles, dolls, role-playing figures or modeling clay, inflatable toys such as balls or rings, non-slip socks, swimming aids, diaper changing pads, sports balls, sports mats, seat cushions, vibrators, massage balls or massage rollers, latex clothing, protective clothing, rain jackets or rubber boots.

[0163] Sixth aspect - Further processing of the plasticizer

[0164] According to a fifth aspect, the invention relates to a method for further processing the following: a plasticizer, preferably a plasticizer obtainable or obtained by the method according to the first aspect, preferably by (g) of the method according to the first aspect, the method comprising one or more steps selected from the group consisting of hydrolysis, hydrogenation and transesterification.

[0165] All details, embodiments and preferred embodiments described above in the part related to the first aspect or the fifth aspect also apply to the sixth aspect.

[0166] In some preferred embodiments of the method for further processing, hydrolysis comprises contacting the plasticizer with water and optionally with a base or an acid and / or optionally in the presence of electromagnetic radiation, preferably light.

[0167] In some preferred embodiments of the method for further processing, hydrogenation comprises contacting the plasticizer with a hydrogen-containing (H2) gas under hydrogenation conditions, preferably hydrogenation conditions allowing the core hydrogenation of an aromatic ring system, more preferably under the conditions disclosed in WO99 / 032427A1.

[0168] Regarding plasticizers, isosorbide esters are excluded with respect to transesterification.

[0169] In some preferred embodiments of the method for further processing, the transesterification comprises contacting the plasticizer with an alcohol having a higher boiling point than the alcohol contained in the alcohol moiety of the plasticizer, optionally in the presence of an acidic or basic catalyst, wherein the acidic catalyst preferably comprises a Bronsted acid and a Lewis acid, and the basic catalyst preferably comprises NaHCO3, more preferably NaHCO3.

[0170] The present invention is further illustrated by the following examples and combinations of examples as indicated by the respective dependencies and backward references. In particular, it should be noted that in each case where a series of examples is mentioned, for example in the context of terms such as "a method as described in any one of Examples 1 to 4", each example in this series is intended to be clearly disclosed to the person skilled in the art, i.e., the wording of this term should be understood by the person skilled in the art as being synonymous with "a method as described in any one of Examples 1, 2, 3 and 4".

[0171] 1. A method for removing a plasticizer from a polymeric material, the method comprising:

[0172] (a) providing a polymeric material that comprises a polymer and a plasticizer, and providing a solvent that comprises γ-valerolactone;

[0173] (b) contacting the polymeric material with the solvent that comprises γ-valerolactone, thereby obtaining a liquid mixture that comprises the solvent, the dissolved polymer, and the dissolved plasticizer.

[0174] 2. The method according to Example 1, further comprising:

[0175] (c) precipitating the polymer from the mixture obtained in (b) by adding an anti-solvent, thereby obtaining a solid residue that comprises the polymer and a liquid phase that comprises the solvent, the anti-solvent, and the dissolved plasticizer.

[0176] 3. The method according to Example 1 or 2, wherein the polymer is preferably a thermoplastic polymer, more preferably a thermoplastic polymer selected from the group consisting of: a copolymer that comprises at least two different monomers in polymerized form, the at least two monomers being selected from the group consisting of: C2 to C 10 monoolefins (which are preferably selected from the group consisting of ethylene, propylene, 1,3-butadiene, 2-chloro-1,3-butadiene, and mixtures of two or more of these olefins), vinyl alcohol, C2 to C of vinyl alcohol 10- alkyl esters, vinyl acetate, vinyl chloride, vinylidene chloride, vinylidene fluoride, tetrafluoroethylene, glycidyl acrylate, glycidyl methacrylate, acrylates of alcohol components having branched or unbranched C1 to C10 alcohols, methacrylates of alcohol components having branched or unbranched C1 to C10 alcohols, vinyl aromatic compounds (preferably styrene), (meth)acrylonitrile, ethylenically unsaturated monocarboxylic or dicarboxylic acids, and maleic anhydride (TP.1); polyvinyl esters (TP.2); polycarbonates (TP.3); polyethers (TP.4); polyether ketones (TP.5); thermoplastic polyurethanes (TP.6); polysulfides (TP.7); polysulfones (TP.8); polyesters (TP.9); alkylene polyesters terephthalate (TP.10); polyhydroxyalkanoates (TP.11); polybutylene succinate (TP.12); polybutylene succinate adipate (TP.13); polyacrylates having the same or different alcohol residues from the group of C4 to C8 alcohols, preferably selected from butanol, hexanol, octanol and 2-ethylhexanol (TP.14); polymethyl methacrylate (TP.15); methyl methacrylate-butyl acrylate copolymer (TP.16); acrylonitrile-butadiene-styrene copolymer (TP.17); ethylene-propylene copolymer (TP.18); ethylene-propylene-diene copolymer (TP.19); polystyrene (TP.20); styrene-acrylonitrile copolymer (TP.21); acrylonitrile-styrene acrylate (TP.22); styrene-butadiene-methyl methacrylate copolymer (TP.23); styrene-maleic anhydride copolymer (TP.24); styrene-methacrylic acid copolymer (TP.25); polyoxymethylene (TP.26); polyvinyl alcohol (TP.27); polyvinyl acetate (TP.28); polyvinyl butyral (TP.29); polyvinyl chloride (TP.30); polycaprolactone (TP.31); polyhydroxybutyric acid (TP.32); polyhydroxyvaleric acid (TP.33); polylactic acid (TP.34); ethyl cellulose (TP.35); cellulose acetate (TP.36); cellulose propionate (TP.37); and cellulose acetate / butyrate (TP.38) and blends of two or more of these polymers.

[0177] 4. The method according to any one of Examples 1 to 3, wherein the polymer is selected from the group consisting of: a copolymer comprising vinyl chloride in polymerized form and at least one additional monomer selected from the group indicated for TP.1 in Example 3; polyvinyl acetate (TP.28); polyvinyl butyral (TP.29); polyvinyl chloride (TP.30); polycaprolactone (TP.31); and blends of two or more of these polymers.

[0178] 5. The method according to any one of embodiments 1 to 4, wherein the polymer comprises polyvinyl chloride (TP.30), and preferably, based on the total weight of the polymer contained in the polymer material of 100 weight-%, at least 90 weight-%, more preferably at least 95 weight-%, even more preferably at least 98 weight-% of the polymer contained in the polymer material is polyvinyl chloride.

[0179] 6. The method according to any one of embodiments 1 to 5, wherein at least 20 weight-% of the polymer material consists of the polymer, and more preferably, the polymer material in the range of 20 to 90 weight-% consists of the polymer, and the total weight of the polymer material is 100 weight-%.

[0180] 7. The method according to any one of embodiments 1 to 6, wherein the solvent containing γ-valerolactone comprises γ-valerolactone and optionally one or more solvents selected from the group consisting of water and organic solvents having a log K in the range of -1.6 to +1.6 OW The one or more solvents are preferably selected from the group consisting of: water, C5 to C12 alkanes, aliphatic C1 to C10 alcohols, C3 to C10 ketones, C2 to C10 cyclohexanones, HO-[C1 to C10 alkyl - O -] n -H--where n is an integer in the range of 2 to 1000, C1 to C10 alkyl - O - C3 to C10 alkyl ethers, C3 to C10 cyclic ethers - optionally substituted by one or more C1 to C6 alkyl groups, C6 to C10 aromatic hydrocarbons - optionally substituted by one or more C1 to C6 alkyl groups, C2 to C10 aliphatic esters, C8 to C11 aromatic esters, C5 to C10 cyclic carboxylic esters (lactones), C3 to C12 amides, preferably R 1 R 2 N - C(=O) - R 3 --where R 1 、R 2 are independently C1 to C4 alkyl groups and R 3 is selected from the group consisting of C1 to C9 alkyl groups, C1 to C10 ester groups and C1 to C6 ether groups, C3 to C6 lactams - optionally substituted by one or more substituents selected from C1 to C6 alkyl groups, C1 to C6 ester groups and C1 to C6 ether groups, and C5 imidazolidines - optionally substituted by one or more C1 to C6 alkyl groups, C5 to C7 imidazolidinones - optionally substituted by one or more C1 to C6 alkyl groups.

[0181] 8. The method according to any one of embodiments 1 to 7, wherein the plasticizer is selected from the group consisting of:

[0182] - Dialkyl cyclohexane - 1,2 - dicarboxylates, wherein the alkyl groups are independently selected from C4 - C13 alkyl groups;

[0183] - Dialkyl cyclohexane-1,3-dicarboxylates, wherein these alkyl groups are independently selected from C4-C13 alkyl groups;

[0184] - Dialkyl cyclohexane-1,4-dicarboxylates, wherein these alkyl groups are independently selected from C4-C13 alkyl groups;

[0185] - Dialkyl phthalates, wherein these alkyl groups are independently selected from C4-C13 alkyl groups;

[0186] - Alkyl aryl phthalates, wherein the alkyl group is selected from C4-C13 alkyl groups and the aryl group is selected from benzyl and phenyl;

[0187] - Dialkyl terephthalates, wherein these alkyl groups are independently selected from C4-C13 alkyl groups;

[0188] - Trialkyl trimellitates;

[0189] - Alkyl benzoates;

[0190] - Dibenzoates of diols;

[0191] - Pentaerythritol esters;

[0192] - Alkyl esters of saturated monocarboxylic acids;

[0193] - Esters of unsaturated monocarboxylic acids;

[0194] - Diesters of saturated dicarboxylic acids;

[0195] - Diesters of unsaturated dicarboxylic acids;

[0196] - Aromatic sulfonic acid esters;

[0197] - Alkyl sulfonic acid esters;

[0198] - Glycerides;

[0199] - Isosorbide esters;

[0200] - Phosphate esters;

[0201] - Tricitrates;

[0202] - Acetylated tricitrates;

[0203] - Alkyl pyrrolidone derivatives;

[0204] - Dialkyl 2,5-furandicarboxylates;

[0205] - Dialkyl 2,5-tetrahydrofurandicarboxylates;

[0206] - Polyesters of aliphatic and / or aromatic polycarboxylic acids and at least diols;

[0207] - Epoxidized vegetable oil;

[0208] - Monoalkyl epoxidized fatty acid esters;

[0209] And mixtures of two or more thereof.

[0210] 9. The method according to any one of Examples 1 to 8, wherein the plasticizer comprises at least cyclohexane-1,2-dicarboxylic acid dialkyl ester having the formula (I)

[0211]

[0212] , wherein R 1 and R 2 are independently selected from the group consisting of branched C4 to C13 alkyl groups and straight-chain C1 to C13 alkyl groups, preferably selected from the group consisting of branched C7 to C11 alkyl groups and straight-chain C7 to C11 alkyl groups, and more preferably R 1 and R 2 are each independently a branched or straight-chain C9 alkyl residue, and more preferably the plasticizer comprises at least diisononyl cyclohexane-1,2-dicarboxylate (DINCH).

[0213] 10. The method according to any one of Examples 1 to 9, wherein the polymer material comprises the plasticizer in an amount in the range of 20 to 490 phr.

[0214] 11. The method according to any one of Examples 1 to 10, wherein contacting the polymer material with the solvent containing γ-valerolactone in (b) is carried out at a temperature T1 below 190 °C, preferably below 180 °C, more preferably below 170 °C, and more preferably at a temperature T1 in the range of 90 °C to <170 °C, more preferably in the range of 95 °C to 165 °C, and more preferably in the range of 100 °C to 150 °C.

[0215] 12. The method according to any one of Examples 1 to 11, wherein contacting the polymer material with the solvent containing γ-valerolactone in (b) is carried out for a period of at least 0.1 h, preferably for a period in the range of 0.1 to 10 h, preferably for a period in the range of 0.1 to 6 h, and more preferably for a period in the range of 0.1 to 4 h.

[0216] 13. The method according to any one of Examples 1 to 12, wherein contacting the polymer material with the solvent containing γ-valerolactone in (b) is carried out at a pressure in the range of 800 to 200,000 hPa.

[0217] 14. The method according to any one of embodiments 1 to 13, wherein in (b), the contacting of the polymeric material with the solvent comprising γ-valerolactone is carried out at a polymer material: solvent ratio by mass in the range of 1:1 to 1:100, more preferably in the range of 1:1 to 1:20, and even more preferably in the range of 1:1 to 1:10.

[0218] 15. The method according to any one of embodiments 2 to 14, wherein step (c) comprises:

[0219] (c.1) adjusting the temperature to a temperature T2 lower than T1, preferably a temperature in the range of 10 °C to 100 °C, more preferably a temperature in the range of 15 °C to 90 °C, and even more preferably a temperature in the range of 20 °C to 80 °C;

[0220] (c.2) precipitating the polymer from the mixture obtained in (b) by adding an anti-solvent at T2;

[0221] Thereby obtaining a solid residue comprising the polymer and a liquid phase comprising the solvent, the anti-solvent, and the dissolved plasticizer.

[0222] 16. The method according to any one of embodiments 2 to 15, wherein the anti-solvent used in step (c) or (c.2) is selected from the group consisting of water, C1-C5 monohydric alcohols, C1-C6 dihydric alcohols, and mixtures of two or more of these solvents, preferably selected from the group consisting of water, C1-C5 monohydric alcohols, C1-C5 dihydric alcohols, and mixtures of two or more of these solvents, more preferably selected from the group consisting of water, C1-C3 monohydric alcohols, and mixtures of two or more of these solvents, and more preferably the anti-solvent used in step (c) or (c.2) contains isopropanol, and even more preferably at least 95 wt-% of the anti-solvent used in step (c) or (c.2) consists of isopropanol.

[0223] 17. The method according to any one of embodiments 2 to 16, wherein the anti-solvent is added in step (c) or (c.2) at an anti-solvent:polymer material ratio by weight in the range of 4:1 to 75:1, preferably in the range of 5:1 to 50:1, and more preferably in the range of 5:1 to 10:1.

[0224] 18. The method according to any one of embodiments 1 to 17, wherein the polymer in the solid residue obtained in (c) or (c.2) contains <5%, preferably <1%, of the amount of plasticizer already present in the polymer material provided in (a).

[0225] 19. The method according to any one of embodiments 1 to 18, which further comprises:

[0226] (d) Separating the solid residue containing the polymer obtained in (c) or (c.2) from the liquid phase containing the solvent, the anti-solvent and the dissolved plasticizer, thereby obtaining the solid residue containing the polymer and the liquid phase containing the solvent, the anti-solvent and the dissolved plasticizer;

[0227] (e) Optionally washing the solid residue obtained in (d) with an anti-solvent;

[0228] (f) Drying the solid residue obtained in (d) or the washed solid residue obtained in (e).

[0229] 20. The method according to any one of Examples 1 to 19, which comprises one or more post-treatment steps, wherein the one or more post-treatment steps preferably comprise

[0230] (g) Separating the solvent and the anti-solvent by distillation and / or separating the solvent from the dissolved plasticizer by distillation, thereby obtaining a liquid fraction preferably containing the plasticizer and one or more liquid fractions containing the solvent and / or the anti-solvent.

[0231] 21. The method according to Example 20, which further comprises at least partially recycling the separated solvent obtained in (g) to (b) and / or at least partially recycling the separated anti-solvent obtained in (g) to (c).

[0232] 22. A polymer obtained or obtainable by the method according to any one of Examples 1 to 21, preferably obtained by (e) and / or (f), and / or a polymer according to Example 18.

[0233] 23. A plasticizer obtained or obtainable by the method according to any one of Examples 1 to 21, preferably obtained by (g).

[0234] 24. Use of a polymer obtained or obtainable by the method according to any one of Examples 1 to 21, preferably obtained by (e) and / or (f), and / or a polymer according to Example 22 for the preparation of a polymer product, preferably a soft polymer product containing at least one plasticizer, wherein the at least one plasticizer is preferably REACH-approved.

[0235] 25. Use of a plasticizer obtained or obtainable by the method according to any one of Examples 1 to 21, preferably obtained by (g), and / or a plasticizer according to Example 23, optionally after one or more post-treatment steps, for the preparation of a soft polymer.

[0236] 26. A method for preparing a product, the method comprising

[0237] (I) Provide the polymer as described in Example 22;

[0238] (II) Prepare a polymer product, preferably a soft polymer product, from the polymer provided in (I) by adding at least one plasticizer, wherein the at least one plasticizer is preferably REACH-approved.

[0239] 27. A method for preparing a soft polymer product, the method comprising

[0240] (I) Provide a plasticizer as described in Example 23, and a polymer;

[0241] (II) Prepare a soft polymer material from the polymer and the plasticizer provided in (I).

[0242] 28. The method as described in Example 27, wherein the polymer provided in (I) is the polymer as defined in any one of Examples 3 to 5.

[0243] 29. A method for further processing: a plasticizer, preferably the plasticizer as described in Example 23, more preferably a plasticizer obtained or obtainable by the method as described in any one of Examples 1 to 21, preferably obtained from (g), the method comprising one or more post-treatment steps selected from the group consisting of hydrolysis, hydrogenation, and transesterification.

[0244] 30. The method for further processing as described in Example 29, wherein hydrolysis comprises contacting the plasticizer with water and optionally with a base or an acid and / or optionally in the presence of electromagnetic radiation, preferably light.

[0245] 31. The method for further processing as described in Example 29, wherein hydrogenation comprises contacting the plasticizer with a gas containing hydrogen (H2) under hydrogenation conditions, preferably hydrogenation conditions that allow the core hydrogenation of an aromatic ring system.

[0246] 32. The method for further processing as described in Example 29, wherein transesterification comprises contacting the plasticizer with an alcohol having a higher boiling point than the alcohol contained in the alcohol moiety of the plasticizer, optionally in the presence of an acidic or basic catalyst.

[0247] The present invention is further illustrated by the following reference examples, comparative examples, and examples.

[0248] Examples

[0249] Method

[0250] Hazen color index:

[0251] The Hazen color index (APHA color number) is determined according to DIN EN ISO 6271:2016-05 (Pt / Co, APHA, ASTM D1209, D5386).

[0252] GPC:

[0253] Sample preparation

[0254] Dissolve approximately 20 mg of the sample in 10 ml of eluent (THF) overnight. Before injection, filter all sample solutions through Macherey-Nagel PTFE (0.2 μm). Place the sealed sample vials in an autosampler.

[0255] Experimental conditions

[0256] Use an Agilent 1200 HPLC system, which consists of an isocratic pump, a vacuum degasser, an autosampler, and a column oven (35 °C). Use a differential refractive index (DRI) and a variable ultraviolet (UVW) detector as detectors. Data acquisition and data processing of conventional SEC data are performed by WinGPC Unichrom, Build 9666 of PSS (Polymer Standards Service). Place in series a combination of an Agilent Plgel 10 μ Guard (7.5 x 50 mm) column and three PLgel MIXED-B columns (7.5 x 300 mm, 10 μ). As the eluent, use THF at a flow rate of 1 mL / min. Inject 100 μL of each sample solution. Obtain calibration with polystyrene standards (Polymer Standards Service) with a narrow molar mass distribution in the molar mass range from M = 580 to M = 6,870,000 g / mol. Extrapolate molar masses outside this range. Set the lowest possible integration limit at 25 ml (approx. M(1800)). Lower molar masses cannot be obtained due to possible polymer additives or solvent impurities.

[0257] GC area %:

[0258] Analyze the sample by gas chromatography (GC), where the method detects the individual components according to their individual retention times in the sample. The concentration of the individual components in the sample is given as their percentage peak area as GC-area %.

[0259] Chemicals

[0260]

[0261] Reference Example 1: General procedure for extracting plasticizers from flexible PVC

[0262] The flexible PVC sample is cut / shredded into pieces and placed in a reaction vessel (e.g., flask, tube, reaction container). GVL is added (at a polymer material:GVL ratio based on mass in the range of 1:1 to 1:100, preferably in the range of 1:1 to 1:10), and the mixture is heated to a temperature in the range of 100 °C to 150 °C by using a suitable heating system (e.g., oil bath, heating block, small equipment container). After 0.1 to 4 h, the mixture is cooled to 80 °C, 60 °C or room temperature, and iPrOH is added at the given temperature to precipitate the PVC. The mixture is filtered at room temperature, thereby obtaining a plasticizer-rich liquid phase containing iPrOH and GVL, and a solid residue containing PVC. The PVC residue is washed with a small amount of iPrOH. The thus obtained PVC residue is dried (e.g., in a vacuum chamber dryer).

[0263] Example 1: Removal of plasticizer from flexible PVC

[0264] The flexible PVC samples are treated as described in Reference Example 1. All of these samples contain a known amount of the same plasticizer Hexamoll DINCH (60 phr, i.e., 36.9 wt-%, based on the total weight of the flexible PVC sample containing 100 wt-% of PVC and plasticizer). After treatment, the plasticizer-rich liquid phase containing iPrOH and GVL is analyzed by GC. The PVC residue is further extracted by a conventional extraction method (using methylal) to determine the residual amount of the plasticizer. The treatment conditions for GVL extraction and the residual amount of Hexamoll DINCH in PVC after GVL extraction, i.e., the amount extracted by using methylal in the subsequent step, are indicated in Table 1 below.

[0265] Table 1

[0266] Experimental results of Examples 1 - 7

[0267]

[0268]

[0269] The molecular weight and dispersity of the polymer before and after treatment are listed in Table 2 below:

[0270] Table 2

[0271] Molecular weight and dispersity

[0272]

[0273] Recycling the solvent GVL and obtaining the plasticizer

[0274] To recycle the solvents used, first iPrOH is distilled off, and then GVL is distilled off. For the distillation of GVL, the following parameters are applied: a temperature in the range of 50 °C to 200 °C, a pressure in the range of 2 hPa to ambient pressure (1013 hPa). Preferably, a temperature in the range of 70 °C to 110 °C and a pressure in the range of 5 to 30 hPa are applied. After evaporation of the solvent, the remaining liquid is Hexamoll DINCH.

[0275] The GVL obtained has a purity of >99% according to GC. For GLV, the Hazen color number after distillation is determined to be 15. For isopropanol, the Hazen color number after distillation is determined to be zero.

[0276] Comparative Example 1: Removal of plasticizers from flexible PVC using different solvents

[0277] The flexible PVC sample is cut / shredded into pieces and placed in a reaction vessel (e.g., flask, tube, reaction vessel). iPrOH is added, and the mixture is stirred for two (2) hours under reflux (about 82 °C), where it is seen that the PVC does not dissolve upon visual inspection - different from Reference Example 1 / Examples 1 - 7, no iPrOH is added to precipitate the PVC. The mixture is cooled to room temperature and then filtered, thereby obtaining a plasticizer-rich liquid phase containing the corresponding solvent and a solid residue containing PVC. The PVC residue is washed with a small amount of iPrOH. The PVC thus obtained is dried (e.g., in a vacuum chamber dryer).

[0278] The dry PVC residue thus obtained is further extracted by a conventional extraction method - the same as in Example 1 (using methylal) - to determine the residual amount of plasticizer. The processing conditions of the solvent extraction and the residual amount of Hexamoll DINCH in the PVC after the solvent extraction, i.e., the amount extracted by using methylal in the subsequent step, are indicated in Table 3 below.

[0279] Comparative Examples 2 and 3: Removal of plasticizers from flexible PVC using different solvents with extended extraction

[0280] The flexible PVC sample is cut / shredded into pieces and placed in a reaction vessel (e.g., flask, tube, reaction vessel). The corresponding solvent is added, and the mixture is stirred for four (4) hours under reflux at an ambient pressure in the range of 1000 to 1050 hPa, where it is seen that the PVC does not dissolve upon visual inspection for both MeOH and the mixture MeOH + methyl propionate - different from Reference Example 1 / Examples 1 - 7, no iPrOH is added to precipitate the PVC. The mixture is cooled to room temperature and then filtered, thereby obtaining a plasticizer-rich liquid phase containing the corresponding solvent and a solid residue containing PVC. The PVC thus obtained is dried (e.g., in a vacuum chamber dryer).

[0281] The dry PVC residue thus obtained was further extracted by a conventional extraction method - the same as in Example 1 (using methylal) - to determine the residual amount of the plasticizer. The processing conditions for the solvent extraction and the residual amount of Hexamoll DINCH in the PVC after the solvent extraction, i.e., the amount extracted by using methylal in the subsequent step, are indicated in Table 3 below.

[0282] Table 3

[0283] Experimental conditions and results for Comparative Examples 1, 2, and 3

[0284]

[0285] Results

[0286] As can be seen when considering Examples 1 - 7 and Comparative Examples 1 - 3, the use of GVL for plasticizer extraction enables a significantly higher removal of plasticizers from flexible PVC, as compared to when using iPrOH, MeOH, or a mixture of MeOH + methyl propionate - more than 95% of the plasticizer is removed when using GVL, while the different solvents give at most 81.6%.

[0287] Cited literature

[0288] WO 01 / 70865A1

[0289] WO 02 / 14413A1

[0290] US 4,071,479 A

[0291] Becker / Braun, Kunststoff-Handbuch, Band 2 / 1: Polyvinylchlorid", 2nd edition, Carl Hanser Verlag, Munich

[0292] ULLMANN'S Encyclopedia of Industrial Chemistry (Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, 2012, Vol. 33, Chapter,, Solvents“, pages 619 to 688; DOI: 10.1002 / 14356007.a24_43

[0293] Handbook of Mechanical Solid-Liquid Separation Pocket Book - April 29, 2004 by Klaus Luckert (Editor)

Claims

1. A method for removing a plasticizer from a polymeric material, the method comprising: (a) providing a polymeric material that comprises a polymer and a plasticizer, and providing a solvent comprising γ-valerolactone; (b) contacting the polymeric material with the solvent comprising γ-valerolactone to obtain a liquid mixture that comprises the solvent, dissolved polymer, and dissolved plasticizer.

2. The method according to claim 1, further comprising: (c) precipitating the polymer from the mixture obtained in (b) by adding an anti-solvent to obtain a solid residue that comprises the polymer and a liquid phase that comprises the solvent, the anti-solvent, and the dissolved plasticizer.

3. The method according to claim 1 or 2, wherein The polymer is a thermoplastic polymer, preferably a thermoplastic polymer selected from the group consisting of: a copolymer that comprises at least two different monomers in polymerized form, the at least two monomers being selected from the group consisting of: C2 to C 10 monoolefins (which are preferably selected from the group consisting of ethylene, propylene, 1,3-butadiene, 2-chloro-1,3-butadiene, and mixtures of two or more of these olefins), vinyl alcohol, C2 to C 10 -alkyl esters of vinyl alcohol, vinyl acetate, vinyl chloride, vinylidene chloride, vinylidene fluoride, tetrafluoroethylene, glycidyl acrylate, glycidyl methacrylate, acrylates of an alcohol component having a branched or unbranched C1 to C10 alcohol, methacrylates of an alcohol component having a branched or unbranched C1 to C10 alcohol, vinyl aromatic compounds (preferably styrene), (meth)acrylonitrile, ethylenically unsaturated monocarboxylic or dicarboxylic acids, and maleic anhydride (TP.1); polyvinyl esters (TP.2); polycarbonates (TP.3); polyethers (TP.4); polyether ketones (TP.5); thermoplastic polyurethanes (TP.6); polysulfides (TP.7); polysulfones (TP.8); polyesters (TP.9); polyalkylene terephthalates (TP.10); polyhydroxyalkanoates (TP.11); polybutylene succinate (TP.12); polybutylene succinate adipate (TP.13); polyacrylates having the same or different alcohol residues from the group of C4 to C8 alcohols, preferably selected from butanol, hexanol, octanol, and 2-ethylhexanol (TP.14); polymethyl methacrylate (TP.15); methyl methacrylate-butyl acrylate copolymer (TP.16); acrylonitrile-butadiene-styrene copolymer (TP.17); ethylene-propylene copolymer (TP.18); ethylene-propylene-diene copolymer (TP.19); polystyrene (TP.20); styrene-acrylonitrile copolymer (TP.21); acrylonitrile-styrene acrylate (TP.22); styrene-butadiene-methyl methacrylate copolymer (TP.23); styrene-maleic anhydride copolymer (TP.24); styrene-methacrylic acid copolymer (TP.25); polyoxymethylene (TP.26); polyvinyl alcohol (TP.27); polyvinyl acetate (TP.28); polyvinyl butyral (TP.29); polyvinyl chloride (TP.30); polycaprolactone (TP.31); polyhydroxybutyric acid (TP.32); polyhydroxyvaleric acid (TP.33); polylactic acid (TP.34); ethyl cellulose (TP.35); cellulose acetate (TP.36); cellulose propionate (TP.37); and cellulose acetate / butyrate (TP.38) and blends of two or more of these polymers.

4. The method according to any one of claims 1 to 3, wherein The polymer is selected from the group consisting of: a copolymer that comprises polymerized vinyl chloride and at least one additional monomer selected from the group indicated for TP.1 in claim 3; polyvinyl acetate (TP.28); polyvinyl butyral (TP.29); polyvinyl chloride (TP.30); polycaprolactone (TP.31); and blends of two or more of these polymers; wherein the polymer preferably comprises polyvinyl chloride (TP.30), and wherein more preferably, based on the total weight of the polymer comprised in the polymeric material at 100 weight-%, at least 90 weight-%, more preferably at least 95 weight-%, more preferably at least 98 weight-% of the polymer comprised in the polymeric material is polyvinyl chloride.

5. The method according to any one of claims 1 to 4, wherein The solvent containing γ-valerolactone contains γ-valerolactone and optionally one or more solvents selected from the group consisting of water and organic solvents having a log K in the range of -1.6 to +1.6 OW The one or more solvents are preferably selected from the group consisting of: water, C5 to C12 alkanes, aliphatic C1 to C10 alcohols, C3 to C10 ketones, C2 to C10 cyclo ketones, HO-[C1 to C10 alkyl - O -] n -H--where n is an integer in the range of 2 to 1000, C1 to C10 alkyl - O - C3 to C10 alkyl ethers, C3 to C10 cyclo ethers - optionally substituted by one or more C1 to C6 alkyl groups, C6 to C10 aromatic hydrocarbons - optionally substituted by one or more C1 to C6 alkyl groups, C2 to C10 aliphatic esters, C8 to C11 aromatic esters, C5 to C10 cyclic carboxylic esters (lactones), C3 to C12 amides, preferably R 1 R 2 N - C(=O) - R 3 --where R 1 、R 2 are independently C1 to C4 alkyl groups and R 3 is selected from the group consisting of C1 to C9 alkyl groups, C1 to C10 ester groups and C1 to C6 ether groups, C3 to C6 lactams - optionally substituted by one or more substituents selected from C1 to C6 alkyl groups, C1 to C6 ester groups and C1 to C6 ether groups, and C5 imidazolidine - optionally substituted by one or more C1 to C6 alkyl groups, C5 to C7 imidazolidinones - optionally substituted by one or more C1 to C6 alkyl groups.

6. The method according to any one of claims 1 to 5, wherein The plasticizer is selected from the group consisting of: - dialkyl cyclohexane-1,2-dicarboxylates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups; - dialkyl cyclohexane-1,3-dicarboxylates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups; - dialkyl cyclohexane-1,4-dicarboxylates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups; - dialkyl phthalates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups; - alkyl aryl phthalates, wherein the alkyl group is selected from C4-C13 alkyl groups and the aryl group is selected from benzyl and phenyl; - dialkyl terephthalates, wherein the alkyl groups are independently selected from C4-C13 alkyl groups; - trialkyl trimellitates; - alkyl benzoates; - dibenzoates of diols; - pentaerythritol esters; - alkyl esters of saturated monocarboxylic acids; - esters of unsaturated monocarboxylic acids; - diesters of saturated dicarboxylic acids; - diesters of unsaturated dicarboxylic acids; - aromatic sulfonates; - alkyl sulfonates; - glycerol esters; - isosorbide esters; - phosphates; - citrate triesters; - acetylated citrate triesters; - alkyl pyrrolidone derivatives; - dialkyl 2,5-furandicarboxylates; - dialkyl 2,5-tetrahydrofurandicarboxylates; - polyesters of aliphatic and / or aromatic polycarboxylic acids with at least diols; - epoxidized vegetable oils; - monoalkyl epoxidized fatty acid esters; and mixtures of two or more thereof.

7. The method according to any one of claims 1 to 6, wherein Contacting the polymeric material with the solvent comprising γ-valerolactone in (b) is carried out at a temperature T1 below 190 °C; and / or wherein, Contacting the polymeric material with the solvent comprising γ-valerolactone in (b) for a period of at least 0.1 h; and / or wherein contacting the polymeric material with the solvent comprising γ-valerolactone in (b) is carried out at a pressure in the range of 800 to 200,000 hPa.

8. The method according to any one of claims 2 to 7, wherein Step (c) comprises: (c.1) Adjusting the temperature to a temperature T2 below T1, preferably a temperature in the range of 10 °C to 100 °C, preferably a temperature in the range of 15 °C to 90 °C, more preferably a temperature in the range of 20 °C to 80 °C; (c.2) Precipitating the polymer from the mixture obtained in (b) by adding an anti-solvent at T2; Thereby obtaining a solid residue comprising the polymer and a liquid phase comprising the solvent, the anti-solvent and the dissolved plasticizer.

9. The method according to any one of claims 2 to 8, wherein The anti-solvent used in step (c) or (c.2) is selected from the group consisting of water, C1-C5 monohydric alcohols, C1-C6 dihydric alcohols and mixtures of two or more of these solvents, preferably selected from the group consisting of water, C1-C5 monohydric alcohols, C1-C5 dihydric alcohols and mixtures of two or more of these solvents, more preferably selected from the group consisting of water, C1-C3 monohydric alcohols and mixtures of two or more of these solvents, more preferably the anti-solvent used in step (c) or (c.2) comprises isopropanol, more preferably at least 95 wt-% of the anti-solvent used in step (c) or (c.2) consists of isopropanol.

10. The method according to any one of claims 1 to 9, further comprising: (d) Separating the solid residue comprising the polymer obtained in (c) or (c.2) from the liquid phase comprising the solvent, the anti-solvent and the dissolved plasticizer, thereby obtaining the solid residue comprising the polymer and the liquid phase comprising the solvent, the anti-solvent and the dissolved plasticizer; (e) Optionally washing the solid residue obtained in (d) with an anti-solvent; (f) Drying the solid residue obtained in (d) or the washed solid residue obtained in (e); wherein the method preferably comprises one or more post-treatment steps, wherein the one or more post-treatment steps preferably comprise (g) Separating the solvent and the anti-solvent by distillation and / or separating the solvent from the dissolved plasticizer by distillation, thereby obtaining a liquid fraction preferably comprising the plasticizer and one or more liquid fractions comprising the solvent and / or the anti-solvent.

11. A polymer obtained or obtainable by the method according to any one of claims 1 to 10, preferably by (e) and / or (f) according to claim 10.

12. A plasticizer obtained or obtainable by the method according to any one of claims 1 to 10, preferably by (g).

13. Use of a polymer obtained or obtainable by the method according to any one of claims 1 to 10, preferably by (e) and / or (f) according to claim 10, and / or a polymer according to claim 11, for the preparation of a polymer product, preferably a soft polymer product comprising at least one plasticizer, wherein the at least one plasticizer is preferably REACH-approved.

14. Use of a plasticizer obtained or obtainable by the method according to any one of claims 1 to 10, preferably by (g) according to claim 10, and / or a plasticizer according to claim 12, optionally after one or more post-treatment steps, for the preparation of a soft polymer.

15. A method for further processing the following: a plasticizer, preferably a plasticizer according to claim 12, more preferably a plasticizer obtained or obtainable by the method according to any one of claims 1 to 10, preferably by (g), the method comprising one or more steps selected from the group consisting of hydrolysis, hydrogenation, and transesterification.

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