Method for obtaining recycled polyol and polyol obtained thereby

Abstract

The present invention includes recovering high-quality polyol from polyurethane waste using a three-phase glycolysis process by contacting polyurethane with a catalyst and a glycolysis compound to obtain a reaction mixture, reacting the reaction mixture for a predetermined reaction time to form a recycled mixture, separating the recycled mixture into three immiscible phases to obtain a high-quality polyol in the polyol phase, and using the recovered polyol phase as a polyol component in a method for producing another polyurethane product. The present invention further relates to the polyol product obtained by the recovery method.

Description

[Technical Field]

[0001] Technical Field The present invention relates to a method for recovering / reclaiming polyol compounds from polyurethane products, where the reclaimed polyol is useful as a starting material for producing new polyurethane products. [Background technology]

[0002] Background technology Polyurethane polymers are generally produced by the reaction of polyisocyanates, particularly diisocyanates, with glycols and hydroxyl-rich compounds such as polyester and polyether polyols. The chemical nature and functionality of the reagents are selected based on the final desired chemical and physical properties of the polyurethane product. Thus, polyurethane products are widely used in large quantities for flexible, semi-rigid, rigid, and reinforced rigid polyurethane foams in furniture and bedding, cushioning in the automotive industry, and often for the good insulating capacity of rigid foams for thermal insulation in, for example, the construction or low-temperature industries, as well as for shoe soles, coatings, adhesives or sealants, and in wind turbine components, such as transportation equipment and solutions, leading edge protection, and lightning protection system elements.

[0003] Due to the variety of uses and widespread industrial applications of polyurethane polymers, their production has increased over the past few decades, resulting in an increase and accumulation of waste products, and growing concerns about the disposal of accumulated waste and / or scrap polyurethane polymers. Today, the majority of polyurethane waste is disposed of by landfilling and incineration. However, these disposal routes, in addition to creating environmental pollution problems, involve economic losses associated with both the land required for landfilling and the expensive materials used to prepare the foams disposed of in these operations.

[0004] Therefore, there is interest in considering the recovery and eventual reuse of such materials. In particular, recycling of plastics and polyurethane foams has been described, primarily consisting of energy recovery, mechanical regeneration, and chemical depolymerization. While energy recovery is not strictly a recycling process, it is a process in which polyurethane is used as fuel to recover its heat and steam. It is well known that the resulting exhaust gases must be strictly controlled to avoid new pollution problems. Mechanical polyurethane waste recycling processes are limited by the thermosetting nature of polyurethane foam, which leads to product quality issues, such as the inability to melt and remold polyurethane waste. While shredding and embedding polyurethane waste as a filler in new materials is possible, the quality of the final product is significantly reduced.

[0005] On the other hand, it is highly desirable to use the chemical components of polyurethanes in the manufacture of new products. Thus, a general objective of chemical regeneration of polyurethanes is to recover one or more of their components, particularly those of commercial interest, such as polyols, which are useful raw materials that can be used to manufacture new polyurethane polymer products, provided that the desired purity can be obtained.

[0006] Examples of chemical depolymerization of polyurethanes are hydrolysis, hydroglycolysis, aminolysis, and glycolysis.

[0007] Hydrolysis and hydroglycolysis of polyurethanes and polyurea-polyurethanes is the decomposition of polyurethanes by treating the polyurethane material with superheated steam or hot water and a basic compound such as ammonia or ammonium hydroxide. When hydroglycolysis is carried out, it involves the presence of a suitable organic solvent such as a polyol or glycol.

[0008] The aminolysis process involves treating polyurethane with a liquid mixture of alkanolamines and a catalyst such as a metal hydroxide at elevated temperatures to yield both a polyol and an amine.

[0009] Glycolysis (or alcoholysis) involves mixing a polyurethane and / or polyurea-polyurethane product with a compound containing at least two reactive hydroxyl groups. The resulting mixture reacts to produce a liquid product containing a mixture of compounds containing hydroxyl end groups, i.e., recycled polyol. This recycled polyol can be used alone or in combination with virgin polyol to prepare polyurethane compounds, but can also be used in various polyurethane, polyurea-polyurethane, and polyisocyanurate applications. Summary of the Invention [Problem to be solved by the invention]

[0010] However, the recycled polyol phase often contains contaminants, which require further purification after the glycolysis compound reacts with the polyurethane product. Therefore, there remains a need in the art to provide a method for obtaining a less contaminated recycled polyol phase without the need for further purification after the glycolysis compound reacts with the polyurethane product.

[0011] Furthermore, there is a need to obtain a cleaner / less contaminated central phase. [Means for solving the problem]

[0012] overview The present invention solves this problem by obtaining high-quality recycled polyol from a polyurethane product using a three-phase process. The polyurethane product is glycolyzed using a catalyst and a glycolysis compound containing at least two hydroxyl groups, specifically selected from one or more long-chain glycols having a selected molecular weight. The reaction mixture is then divided into a top phase, a middle phase, and a bottom phase. The top phase is formed primarily by the recycled polyol (which may contain a small amount of unreacted glycolysis compound). The middle phase typically contains the solvent (i.e., the glycolysis compound). The middle phase can be further used in another round of the process, i.e., another batch.

[0013] By using a specific glycolysis compound, three phases are obtained according to the present invention, and the difference between the recycled polyol from the polyurethane product and the glycolysis compound used results in good phase separation between these two phases, resulting in less contamination of the polyol phase with the glycolysis compound compared to methods using glycolysis compounds with molecular weights other than that of the recycled polyol. This phase separation can be further optimized by utilizing a glycolysis compound with a density and / or molecular weight different from that of the recycled polyol. In this way, a clearer and better phase separation between the two phases is obtained, and the glycolysis compound, being denser, preferably forms a layer below the recycled polyol, which is less dense. Therefore, it is disclosed herein that the recycled polyol does not need to be completely similar to the glycolysis compound used, and vice versa.

[0014] Typical polyols regenerated by the methods disclosed herein have a concentration of from about 0.98 to about 1.05 g / cm 3 However, it is a higher functionality polyether polyol sucrose based on sucrose and has a density of 1.11 g / cm 3 One glycolysis compound used herein, PEG 400, can have a density of about 1.13 g / cm 3 Glycerol has a density of 1.25 g / cm3 It has a density of

[0015] Furthermore, this combination of polyurethane and glycolysis compound provides better separation between the top and bottom phases by the middle phase, allowing the remaining unreacted glycolysis compound to be reused in another polyol regeneration process without the need for further purification.

[0016] Thus, a method for preparing recycled polyol includes contacting a polyurethane product with a glycolysis compound containing at least two hydroxyl groups and reacting the polyurethane and the glycolysis compound at elevated or elevated temperatures in the presence of a catalyst. By using an excess of the glycolysis compound and a suitable glycolysis compound, the reaction product is divided into three phases, the top layer being mainly formed by the recovered polyol from the polyurethane, the middle layer being formed by the excess glycolysis compound, and the bottom layer being formed by the isocyanate derivatives and aromatic dicarbamates obtained when the polyurethane is hydrolyzed. If necessary, the top layer / phase can be further purified, for example, by liquid-liquid extraction using an aqueous phase, and the excess glycolysis compound in the middle phase can be regenerated and reused in the process by vacuum distillation if higher purity is required.

[0017] The central layer formed by the excess glycolysis compound may also be disclosed herein as the central layer / phase formed by the solvent because the process preferably uses a molar excess of the glycolysis compound as the solvent for the process.

[0018] Thus, in a first aspect, there is provided a method for obtaining recycled polyol from a first polyurethane and using said polyol as a component in a second polyurethane, the method comprising: a. contacting a first polyurethane with a catalyst and a molar excess of a glycolysis compound to obtain a reaction mixture, wherein the glycolysis compound is selected from one or more long-chain glycols containing at least two hydroxyl groups and having a molecular weight of 180 to 1100 g / mol; b. reacting the reaction mixture of step a) at a reaction temperature of 170°C to 220°C for a predetermined reaction time of 30 minutes to 240 minutes to form a regenerated mixture; c. Separating the regenerated mixture of step b) into at least three immiscible phases to obtain at least a recovered polyol phase, a glycolysis compound phase, and a waste phase; d. using the recovered polyol phase as a polyol component in a method for producing a second polyurethane; wherein the glycolysis compound and the first polyurethane are selected such that the glycolysis compound has a higher density than the recycled polyol.

[0019] The present invention thus provides a method in which a specific combination of polyurethane and glycolysis compound results in a phase-split reaction in which the reaction mixture separates into three phases after the final reaction. In this way, the present invention solves the above-mentioned problems by obtaining high-quality recovered polyol from polyurethane products in one phase and residual glycolysis compound in another phase. This results in better phase separation and therefore less contamination of the polyol phase. Furthermore, by having a third phase containing residual isocyanate derivatives and aromatic dicarbamates, the residual glycolysis compound can be directly used in another process cycle for polyol regeneration without further purification. Therefore, in one or more embodiments, the glycolysis compound phase is reused as glycolysis compound in another process to obtain recycled polyol.

[0020] The recycled polyol obtained from the process is less contaminated, and because the recycled polyol is used in-process as a polyol component in a process for producing another polyurethane product, the resulting polyurethane product has better quality compared to using recycled polyol that is more contaminated with glycolysis compounds or other derivatives after the final reaction. Preferably, the recycled polyol is used without further purification in a process for producing another polyurethane product. Thus, in one or more embodiments, the recovered polyol phase is used directly as a polyol component in a process for producing new polyurethane.

[0021] The waste phase disclosed herein may also be referred to as the isocyanate derivative and aromatic dicarbamate phase, since in most cases some of the compounds may be found in this phase. However, depending on the isocyanate derivative and aromatic dicarbamate formed, they may be found in a separate phase, which will not affect the recycling of the polyol. Other components may also be found in the waste phase.

[0022] In a second aspect, disclosed herein is a polyurethane prepared from a polyol mixture and one or more isocyanates, wherein the polyol mixture comprises at least 5 wt.% recovered polyol phase obtained from a process for obtaining recycled polyol according to the first aspect, such as at least 10 wt.%, for example at least 15 wt.%, such as at least 20 wt.%, for example at least 25 wt.%, such as at least 30 wt.%, or such as at least 35 wt.% recovered polyol phase.

[0023] The glycolysis compound may be further defined depending on the starting polyurethane, and thus in one or more embodiments, the glycolysis compound is selected from one or more polyethylene glycols having a molecular weight of 380-420 g / mol, such as PEG 400.

[0024] The polyurethane may be an elastic polyurethane, and thus, in one or more embodiments, the first polyurethane and / or the second polyurethane is a polyurethane elastomer. "Elastomer" refers to a polymer that is viscoelastic (i.e., both viscous and elastic), has weak intermolecular forces relative to other materials, generally a low Young's modulus, and a high strain at break. Alternatively, the polyurethane may be a polyurethane foam, and thus, in one or more embodiments, the first polyurethane and / or the second polyurethane is a polyurethane foam.

[0025] Preferably, when the reaction mixture is at an elevated temperature, either rotating the regenerated mixture or maintaining the reaction mixture for a predetermined period of time can preferably result in clearer phase separation (i.e., fewer contaminants between the two phases). This ensures that most of the remaining unreacted glycolysis compounds separate into the middle phase, while the resulting recycled polyol and isocyanate derivatives and aromatic dicarbamate residues separate into upper and bottom layers, respectively. This further improves the purity of each phase, thereby further enabling reuse of the recycled polyol and / or unreacted glycolysis compounds without further purification. Thus, in one or more embodiments, separation step c) involves rotating the regenerated mixture at at least 3,000 to 10,000 rpm for a predetermined period of time, maintaining or heating the regenerated mixture to at least 30°C, e.g., at least 40°C, for a predetermined period of at least 15 minutes, and / or allowing the regenerated mixture to stand for a predetermined period of at least 30 minutes. In one or more embodiments, the separating step c) comprises leaving the regeneration mixture for a predetermined period of at least 45 minutes, such as a predetermined period of at least 1 hour, such as a predetermined period of at least 6 hours, or for example a predetermined period of 12 to 48 hours.

[0026] The recycled polyol obtained in the upper phase is used in step d) as a component in a process for producing another polyurethane, which may have similar or different properties compared to the polyurethane product being recycled. Due to the high purity of the recycled polyol, the polyol may be used in a greater weight percentage, such as up to 60-70 wt. %, depending on the physical and chemical properties required for the polyurethane product being produced. Thus, in one or more embodiments, the polyol phase is used in an amount of up to 60 wt. %, e.g., 30-50 wt. %, of the total amount of reaction mixture used to produce the second polyurethane. Furthermore, the polyurethane product from which the polyol is recycled may be the same polyurethane product as that produced by the recycled polyol. Thus, in one or more embodiments, the first and second polyurethanes are substantially the same polyurethane.

[0027] After the final reaction, during step c), the method can further cool the reaction mixture by leaving it at room temperature. The reaction can also be actively cooled by cooling the regeneration mixture to a predetermined temperature. Preferably, a temperature higher than room temperature is actively applied to the reaction mixture, such as a temperature of 30°C or higher. Thus, in one or more embodiments, the method further comprises cooling the regeneration mixture before separating the regeneration mixture in step c), the cooling being carried out at a temperature of about 30°C to about 60°C, e.g., about 40°C to about 50°C. The reaction mixture can be maintained at the cooled temperature for a predetermined period of time, as disclosed herein.

[0028] Additionally, various catalysts can be used in the disclosed methods, such as potassium hydroxide or metal acetates, e.g., zinc acetate. In one or more embodiments, the catalyst is selected from metal acetates, such as zinc acetate. The catalyst can be used in various weight percents based on the weight of the polyurethane product from which the polyol is to be regenerated. Such an amount can be, for example, 2-4 weight percent based on 100 weight percent polyurethane. Thus, in one or more embodiments, the catalyst is at a concentration of 2-4 weight percent relative to 100 weight percent of the first polyurethane.

[0029] The ratio between the polyurethane from which the polyol is regenerated and the glycolysis compound can vary. However, a molar excess of the glycolysis compound relative to the polyol compound cleaved in the polyurethane product is preferred. This can be achieved by always having an equivalent or excess amount of glycolysis compound relative to the polyurethane product, measured by weight. Thus, in one or more embodiments, the polyurethane and the glycolysis compound are mixed in a ratio of 1:1 to 1:2. This ratio is the ratio between the weight of the polyurethane and the weight of the glycolysis compound. For example, if 10 kg of polyurethane is processed in this manner, 10 to 20 kg of the glycolysis compound can be used.

[0030] Other parameters of the process, such as reaction temperature and reaction time, can be varied. Thus, in one or more embodiments, the reaction temperature is 180°C to 190°C. In one or more embodiments, the reaction temperature is 170°C to 190°C. In one or more embodiments, the reaction temperature is 180°C to 185°C. In one or more embodiments, the reaction temperature is 180°C to 220°C. In one or more embodiments, the reaction temperature is 190°C to 220°C. In one or more embodiments, the reaction temperature is 190°C to 210°C. In one or more embodiments, the reaction temperature is 195°C to 205°C.

[0031] In one or more embodiments, the predetermined reaction time is 30 minutes to 150 minutes, for example, 60 minutes to 100 minutes. In one or more embodiments, the predetermined reaction time is 60 minutes to 120 minutes, for example, 60 minutes to 80 minutes. In one or more embodiments, the predetermined reaction time is 60 minutes to 240 minutes. In one or more embodiments, the predetermined reaction time is 90 minutes to 220 minutes. In one or more embodiments, the predetermined reaction time is 120 minutes to 200 minutes. In one or more embodiments, the predetermined reaction time is 150 minutes to 200 minutes. In one or more embodiments, the predetermined reaction time is 170 minutes to 190 minutes.

[0032] The reaction time and temperature are optimized to maximize the reaction between the carbamate groups in the regenerated polyurethane and the hydroxyl groups of the glycolysis compound, thereby cleaving the original polyols used to make the polyurethane from the carbamate groups, releasing these polyols. The reaction time and temperature are further optimized to minimize the occurrence of any side reactions.

[0033] Furthermore, step a) of the method may be divided into three steps. In one or more embodiments, step a) comprises: a1) providing a molar excess of a glycolysis compound; a2) adding a first polyurethane to a glycolysis compound to obtain a pre-reaction mixture; a3) adding a catalyst to the pre-reaction mixture of step a2) to obtain a reaction mixture; Includes:

[0034] Furthermore, in a third aspect, there is provided a method for obtaining recycled polyol from a first polyurethane and using said polyol as a component in a second polyurethane, the method comprising: a. contacting a first polyurethane with a catalyst and a molar excess of a glycolysis compound to obtain a reaction mixture, wherein the glycolysis compound is selected from one or more long-chain glycols containing at least two hydroxyl groups and having a molecular weight of 180 to 1100 g / mol; b. reacting the reaction mixture of step a) at a reaction temperature of 170°C to 200°C for a predetermined reaction time of 30 minutes to 150 minutes to form a regenerated mixture; c. Separating the regenerated mixture of step b) into at least three immiscible phases to obtain at least a recovered polyol phase, a glycolysis compound phase, and an isocyanate derivative and aromatic dicarbamate phase; d. using the recovered polyol phase as a polyol component in a method for producing a second polyurethane; Disclosed herein is a method comprising:

[0035] The present disclosure will become apparent from the detailed description set forth below. The detailed description and specific examples disclose preferred embodiments of the present disclosure by way of example only. Those skilled in the art will understand that, with the guidance of the detailed description, changes and modifications are possible within the scope of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0036] Detailed Description Any description herein of any aspect or embodiment of the invention using terms such as "comprise," "have," "include," or "contain," in connection with one or more elements, is intended to support similar aspects or embodiments of the invention that "consist," "consist essentially of," or "substantially comprise" that one or more elements, unless otherwise stated or clearly contradicted by context; for example, a composition described herein as comprising a particular element should be understood to also describe a composition consisting of that element, unless otherwise stated or clearly contradicted by context. It will be further understood that, as used herein, the terms "comprise," "comprising," "including," and / or "comprising" specify the presence of stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0037] As used herein, the singular forms "a," "an," and "the" are intended to include plural forms such as "at least one," unless the content clearly dictates otherwise. "At least one" should not be construed as limiting "a" or "an."

[0038] Unless otherwise specified, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by those skilled in the art to which this invention belongs. Unless expressly defined herein, terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the relevant art, and will be further understood not to be interpreted in an idealized or overly formal sense.

[0039] The effects and features of the second aspect are generally similar to those described above and below in relation to the first aspect, and embodiments mentioned in relation to the first aspect are largely compatible with the second aspect.

[0040] The use of any examples or exemplary language (e.g., "etc.") provided herein is intended merely to further clarify the invention and does not pose a limitation on the scope of the invention unless specifically claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention.

[0041] As mentioned above, the present invention solves the problem of providing a method for obtaining a cleaner recycled polyol phase after reacting a glycolysis compound with a polyurethane product without the need for further purification. The present invention solves this problem by providing a high-quality recycled polyol from a polyurethane product using a three-phase process, in which the polyurethane product is glycolyzed using a catalyst, and the glycolysis compound is selected from one or more long-chain glycols containing at least two hydroxyl groups and having a specifically selected molecular weight. The reaction mixture is then divided into a top phase, a middle phase, and a bottom phase, with the top phase being formed primarily by the recycled polyol (which may contain a small amount of unreacted glycolysis compound). The middle phase can be further used in another round of the process. Accordingly, one aspect of the present invention relates to a method for obtaining recycled polyol from a first polyurethane and using the polyol as a component in a second polyurethane, the method comprising the steps of: a) contacting the first polyurethane with a catalyst and a molar excess of a glycolysis compound to obtain a reaction mixture, wherein the glycolysis compound contains at least two hydroxyl groups and is selected from one or more long-chain glycols having a molecular weight of 180 to 1100 g / mol; b) reacting the reaction mixture of step a) at a reaction temperature of 170°C to 200°C for a predetermined reaction time of 30 to 150 minutes to produce a recycled mixture; c) separating the recycled mixture of step b) into at least three immiscible phases to obtain at least a recycled polyol phase, a glycolysis compound phase, and an isocyanate derivative and aromatic dicarbamate phase; and using the recycled polyol phase as a polyol component in a method for producing the second polyurethane.Another aspect of the present invention relates to a method for obtaining recycled polyol from a first polyurethane and using the polyol as a component in a second polyurethane, the method comprising the steps of: a) contacting the first polyurethane with a catalyst and a molar excess of a glycolysis compound to obtain a reaction mixture, wherein the glycolysis compound is selected from one or more long-chain glycols containing at least two hydroxyl groups and having a molecular weight of 180 to 1100 g / mol; b) reacting the reaction mixture of step a) at a reaction temperature of 170°C to 220°C for a predetermined reaction time of 30 to 240 minutes to produce a recycled mixture; c) separating the recycled mixture of step b) into at least three immiscible phases to obtain at least a recovered polyol phase, a glycolysis compound phase, and a waste phase; and using the recovered polyol phase as a polyol component in a method for producing a second polyurethane, wherein the glycolysis compound and the first polyurethane are selected such that the glycolysis compound has a higher density than the recycled polyol.

[0042] In other words, the present invention particularly relates to a method for glycolysis of polyurethane by contacting scrap polyurethane with a glycolysis compound selected from one or more long-chain glycols containing at least two hydroxyl groups and having a molecular weight of 180 to 1100 g / mol and a catalyst that promotes the glycolysis of polyurethane, and reacting them at high temperature, and then dividing the mixture into at least three phases: an upper phase, a middle phase, and a lower phase, wherein the upper phase is mainly formed by recovered polyol from the polyurethane, the middle phase is formed by the remaining unreacted glycolysis compound, and the lower phase is other by-products.

[0043] The upper phase / recovered polyol phase is used as a further polyol or mixed with fresh polyol in further polyurethane production by incorporating it into the reaction mixture together with an isocyanate in the presence of a suitable catalyst and other commonly used additives.

[0044] In another aspect, the present invention relates to a polyurethane prepared from a polyol mixture and one or more isocyanates, wherein the polyol mixture comprises at least 5 wt.% recovered polyol phase obtained from the process for obtaining recycled polyol disclosed herein, such as at least 10 wt.%, for example at least 15 wt.%, such as at least 20 wt.%, for example at least 25 wt.%, such as at least 30 wt.%, or such as at least 35 wt.% recovered polyol phase.

[0045] The polyurethane can be an elastomeric polyurethane, and thus, in one or more embodiments, the first polyurethane and / or the second polyurethane is a polyurethane elastomer. Alternatively, the polyurethane can be a polyurethane foam, and thus, in one or more embodiments, the first polyurethane and / or the second polyurethane is a polyurethane foam.

[0046] Depending on the physical and chemical properties desired for the new polyurethane, reclaimed polyol can be used in various amounts when preparing the new polyurethane. Thus, in one or more embodiments, the polyol mixture comprises at least 10 wt. % of the reclaimed polyol phase obtained from the process for obtaining recycled polyol disclosed herein. In another embodiment, the polyol mixture comprises at least 15 wt. % of the reclaimed polyol phase obtained from the process for obtaining recycled polyol disclosed herein. In yet another embodiment, the polyol mixture comprises at least 20 wt. % of the reclaimed polyol phase obtained from the process for obtaining recycled polyol disclosed herein. In a further embodiment, the polyol mixture comprises at least 25 wt. % of the reclaimed polyol phase obtained from the process for obtaining recycled polyol disclosed herein. In yet another embodiment, the polyol mixture comprises at least 30 wt. % of the reclaimed polyol phase obtained from the process for obtaining recycled polyol disclosed herein. In a further embodiment, the polyol mixture comprises at least 35 wt. % of the reclaimed polyol phase obtained from the process for obtaining recycled polyol disclosed herein.

[0047] In one or more embodiments, the polyol mixture comprises 70 wt. % or less of a recycled polyol phase obtained from the process for obtaining recycled polyol disclosed herein, such as 60 wt. % or less, e.g., 50 wt. % or less, or, for example, 40 wt. % or less of a recycled polyol phase obtained from the process for obtaining recycled polyol disclosed herein.

[0048] In this regard, weight basis is meant to be compared to the weight of the entire mixture, including both the polyol and the isocyanate, used to make the new polyurethane.

[0049] In one or more embodiments, the glycolysis compound phase is recycled as a glycolysis compound in another process to obtain recycled polyol. Recycling of the glycolysis compound is possible because the recycled mixture is processed into at least three immiscible phases, which results in less contamination of excess spent glycolysis compound after separation. Recycling of the glycolysis compound makes the process more environmentally friendly and less expensive for multiple runs.

[0050] The glycolysis compound may be selected from one or more polyethylene glycols having a molecular weight of 180 to 1100 g / mol, such as PEG 200, PEG 400, PEG 600, PEG 800, or PEG 1000. Thus, in one or more embodiments, the glycolysis compound is selected from one or more polyethylene glycols having a molecular weight of 180 to 1100 g / mol, such as PEG 200, PEG 400, PEG 600, PEG 800, or PEG 1000.

[0051] In one or more embodiments, the glycolysis compound is selected from one or more polyethylene glycols, such as PEG 400, having a molecular weight of 380-420 g / mol.

[0052] In one or more embodiments, the glycolysis compound is selected from PEG 400, PEG 600, and / or PEG 800. In one or more embodiments, the glycolysis compound is PEG 400.

[0053] Phase separation is preferably optimized by utilizing different densities between the compounds to be separated. Thus, in one or more embodiments, the compound for glycolysis has a different density and / or molecular weight than the regenerated polyol obtained by regeneration. In one or more embodiments, the density of the compound for glycolysis is greater than or equal to 1.1 g / cm. 3 In one or more embodiments, the density of the glycolysis compound is 1.2 g / cm or greater (measured at 20°C). 3 In one or more embodiments, the density of the glycolysis compound is 1.15 g / cm or greater (measured at 20°C). 3 In one or more embodiments, the density of the glycolysis compound is 1.20 g / cm or greater (measured at 20°C). 3 In one or more embodiments, the density of the glycolysis compound is 1.13 g / cm or greater (measured at 20°C). 3 or more (measured at 20°C).

[0054] In one or more embodiments, the recycled polyol has a density of 1.1 g / cm 3 or less (measured at 20°C). In one or more embodiments, the density of the recycled polyol is 1.2 g / cm 3 or less (measured at 20°C). In one or more embodiments, the density of the recycled polyol is 1.15 g / cm 3 or less (measured at 20°C). In one or more embodiments, the density of the recycled polyol is 1.20 g / cm 3 or less (measured at 20°C).

[0055] In one or more embodiments, the density of the glycolysis compound is 1.1 g / cm 3 (measured at 20°C), and the density of the recycled polyol is 1.1 g / cm 3In one or more embodiments, the density of the glycolysis compound is less than 1.2 g / cm (measured at 20°C). 3 (measured at 20°C), and the density of the recycled polyol is 1.2 g / cm 3 In one or more embodiments, the density of the glycolysis compound is less than 1.15 g / cm 3 (measured at 20°C), and the density of the recycled polyol is 1.15 g / cm 3 In one or more embodiments, the density of the glycolysis compound is less than 1.20 g / cm (measured at 20°C). 3 (measured at 20°C), and the density of the recycled polyol is 1.20 g / cm 3 In one or more embodiments, the density of the glycolysis compound is less than 1.12 g / cm (measured at 20°C). 3 or more (measured at 20°C), and the density of the recycled polyol is 1.11 g / cm 3 or less (measured at 20°C).

[0056] In one or more embodiments, the recycled polyol is selected from difunctional polyether polyols, trifunctional polyether polyols, glycerin-based trifunctional polyether polyols, sucrose-based higher functionality polyether polyols, and / or polytetramethylene ether glycol (PTMEG).

[0057] After step b) is completed and stopped, the regenerated mixture can be cooled or is cooled, and then the regenerated mixture is divided into at least three phases, which are collected separately by mechanical operations such as decantation or centrifugation. The upper phase obtained is mainly formed by the regenerated / recovered polyol obtained from the reacted polyurethane, the middle phase mainly contains the excess glycolysis compound used, and the lower phase mainly contains by-products such as isocyanate derivatives and aromatic dicarbamates.

[0058] In one or more embodiments, the method further comprises cooling the regenerated mixture prior to separating the regenerated mixture in step c), wherein the cooling is performed at a temperature of about 30°C to about 60°C, for example, about 40°C to about 50°C.

[0059] In one or more embodiments, the method further comprises cooling the regenerated mixture prior to separating the regenerated mixture in step c), wherein the cooling is carried out at a temperature of about 30°C to about 60°C, for example about 40°C to about 50°C, and the separation step c) is carried out by maintaining the temperature obtained by the cooling for a predetermined period of at least 15 minutes, for example for a predetermined period of at least 1 hour, for example for a predetermined period of at least 6 hours, or for example for a predetermined period of 12 to 48 hours.

[0060] In one or more embodiments, the separating step c) is by rotating the regenerated mixture at at least 3000-10000 rpm for a predetermined period of time, and / or by maintaining or heating the regenerated mixture to at least 30°C, e.g., at least 40°C, for a predetermined period of at least 15 minutes, and / or by allowing the regenerated mixture to stand for a predetermined period of at least 30 minutes.

[0061] Rotation of the regeneration mixture at at least 3,000-10,000 rpm for a predetermined period of time can be, for example, 1,200 g force (RCF) at 3,000 RPM for 2 minutes. A different RCF and predetermined period can be selected based on the setup and glycolysis compound used.

[0062] In one or more embodiments, the separating step c) involves rotating the renaturation mixture at at least 3,000-10,000 rpm for a predetermined period of time. Again, the rotation of the renaturation mixture at at least 3,000-10,000 rpm for a predetermined period of time can be, for example, 1,200 g-force (RCF) at 3,000 RPM for 2 minutes. Other RCFs and predetermined periods can be selected based on the setup and glycolysis compound used.

[0063] In one or more embodiments, the separating step c) is by maintaining or heating the refolding mixture to at least 30°C, e.g., at least 40°C, for a predetermined period of at least 15 minutes, e.g., at least 1 hour, e.g., at least 6 hours, or e.g., 12 to 48 hours. This embodiment may preferably be combined with the embodiment of cooling the refolding mixture before separating it in step c), wherein the cooling is at a temperature of about 30°C to about 60°C.

[0064] In one or more embodiments, the separating step c) comprises leaving the regeneration mixture for a predetermined period of at least 30 minutes, such as a predetermined period of at least 45 minutes, such as a predetermined period of at least 1 hour, such as a predetermined period of at least 6 hours, or for example a predetermined period of 12 to 48 hours.

[0065] In one or more embodiments, the regeneration mixture created in step b) is actively or passively cooled to a temperature of 30-60°C and maintained at the set temperature for a period of 12-48 hours to form and separate the at least three immiscible phases in step c).

[0066] In one or more embodiments, the created refolding mixture of step b) is actively or passively cooled to a temperature of 30-60°C and maintained at the set temperature while centrifuging the refolding mixture at 3000-10000 RPM to form and separate the at least three immiscible phases of step c).

[0067] In one or more embodiments, the recovered polyol phase is used directly as the polyol component in a process for making new polyurethanes.

[0068] In one or more embodiments, the polyol phase is used in an amount of up to 60 wt %, e.g., 30-50 wt %, of the total amount of reaction mixture used to prepare the second polyurethane. In one or more embodiments, the polyol phase is used in an amount of up to 40 wt %, e.g., 20-40 wt %, of the total amount of reaction mixture used to prepare the second polyurethane. In one or more embodiments, the polyol phase is used in an amount of up to 35 wt %, e.g., 10-35 wt %, of the total amount of reaction mixture used to prepare the second polyurethane.

[0069] In one or more embodiments, one or more of the recovered polyol phase, and / or the glycolysis compound phase, and / or the isocyanate derivative and aromatic dicarbamate phase are filtered after separation step c).

[0070] In one or more embodiments, the first and second polyurethanes are substantially the same polyurethane.

[0071] In one or more embodiments, the first polyurethane is prepared from at least a virgin polyol mixture and one or more isocyanates, and the second polyurethane is prepared from at least a recycled polyol mixture and one or more isocyanates.

[0072] In one or more embodiments, the first polyurethane is prepared from only a virgin polyol mixture and one or more isocyanates, and the second polyurethane is prepared from a combination of one or more recycled polyol mixtures, one or more virgin polyol mixtures, and one or more isocyanates.

[0073] In one or more embodiments, the first polyurethane is chopped, ground, cut, scraped, and / or granulated prior to contacting the first polyurethane with the catalyst and a molar excess of the glycolysis compound to obtain a reaction mixture.

[0074] In practicing the method of the present invention, the polyurethane obtained for regeneration is preferably ground, scraped, or crushed to particles of relatively small size, preferably having an average diameter of 1 mm to 5 cm, in order to reduce the time required for the reaction to occur.

[0075] In one or more embodiments, prior to contacting the first polyurethane with the catalyst and a molar excess of the glycolysis compound to obtain a reaction mixture, the first polyurethane is chopped, crushed, cut, scraped, and / or granulated to a diameter of 3 mm or less, and in one or more embodiments, the diameter is 2 mm or less, for example, 1 mm or less.

[0076] In one or more embodiments, the first and / or second polyurethane has a Shore A of 50A to 90A. Shore hardness can be measured using a durometer and refers to the value determined by penetrating the durometer indenter foot into the sample being tested. The Shore A hardness scale measures the hardness of mold rubbers, for example. These are generally softer, more flexible materials, but the scale provides an indication of whether they are very soft or harder. In addition to soft rubbers, semi-rigid plastics can also be tested on the Shore A scale, but at a higher level.

[0077] In one or more embodiments, the first and / or second polyurethane has a Shore D hardness of up to 90 D. The Shore D hardness scale measures the hardness of hard rubbers, semi-hard plastics, and hard plastics.

[0078] In one or more embodiments, the first and / or second polyurethane has a Shore of 50A to 90D, such as 60A to 90D, for example 50A to 90D, such as 100A to 90D, or the first and / or second polyurethane has a Shore of 50A to 85D, such as 50A to 80D, for example 50A to 70D, for example 50A to 60D, for example 50A to 50D or for example 50A to 40D.

[0079] In one or more embodiments, the first and / or second polyurethane is formed from at least methylene diphenyl diisocyanate (MDI) and polyether polyol comonomers.

[0080] In one or more embodiments, the catalyst is selected from metal acetates, such as zinc acetate.

[0081] The glycolysis of the polyurethane is carried out in the presence of a catalyst to increase the reaction rate. The catalyst may be present in an amount of 0.001 to 10% by weight, for example, 0.01 to 10% by weight, for example, 0.1 to 10% by weight, for example, 1 to 10% by weight, for example, 1 to 8% by weight, for example, 1 to 6% by weight, preferably 2 to 4% by weight, based on the weight of the polyurethane.

[0082] In one or more embodiments, the catalyst is at a concentration of 2-4% by weight relative to 100% by weight of the first polyurethane.

[0083] In one or more embodiments, the polyurethane and the glycolysis compound are mixed in a ratio of 1:1 to 1:2, where X:Y refers to a weight-to-weight ratio, e.g., if the ratio I is 1:2 and 1 kg of polyurethane is to be regenerated, then 2 kg of glycolysis compound are used in the process for the regeneration of said 1 kg of polyurethane.

[0084] In one or more embodiments, the reaction temperature is 180°C to 190°C. In one or more embodiments, the reaction temperature is 170°C to 190°C. In one or more embodiments, the reaction temperature is 180°C to 185°C. In one or more embodiments, the reaction temperature is 180°C to 220°C. In one or more embodiments, the reaction temperature is 190°C to 220°C. In one or more embodiments, the reaction temperature is 190°C to 210°C. In one or more embodiments, the reaction temperature is 195°C to 205°C.

[0085] In one or more embodiments, the predetermined reaction time is 30 minutes to 150 minutes, for example, 60 minutes to 100 minutes. In one or more embodiments, the predetermined reaction time is 60 minutes to 120 minutes, for example, 60 minutes and 80 minutes. In one or more embodiments, the predetermined reaction time is 60 minutes to 240 minutes. In one or more embodiments, the predetermined reaction time is 90 minutes to 220 minutes. In one or more embodiments, the predetermined reaction time is 120 minutes to 200 minutes. In one or more embodiments, the predetermined reaction time is 150 minutes to 200 minutes. In one or more embodiments, the predetermined reaction time is 170 minutes to 190 minutes.

[0086] In one or more embodiments, step a) comprises: a1) providing a molar excess of a glycolysis compound; a2) adding a first polyurethane to a glycolysis compound to obtain a pre-reaction mixture; a3) adding a catalyst to the pre-reaction mixture of step a2) to obtain a reaction mixture; Includes:

[0087] In one or more embodiments, the step of adding the first polyurethane to the glycolysis compound occurs over a predetermined period of time that is less than 5 minutes.

[0088] In one or more embodiments, the glycolysis compound in step a1) is heated to the reaction temperature before adding the first polyurethane in step a2).

[0089] In one or more embodiments, the first polyurethane is heated to a temperature above 60° C. before adding the first polyurethane to the glycolysis compound in step a2).

[0090] The reaction can be carried out in air. Alternatively, the reaction can be carried out in an inert gas atmosphere. A nitrogen atmosphere can be used. This produces a product with less oxidative decomposition and therefore less color and fewer impurities than when the reaction is carried out in air. In one or more embodiments, the method is carried out under an inert atmosphere, such as under a N2 atmosphere, before separating the regenerated mixture in step c).

[0091] In one or more embodiments, the polyurethane is further prepared from a chain extender, such as butanediol.

[0092] In one or more embodiments, the method further comprises a first further purification step of the recovered polyol phase, the first further purification step comprising extraction with a weakly acidic aqueous solution, water, brine, propylene oxide, or ethylene oxide.

[0093] In one or more embodiments, the method further comprises a second purification step of the glycolysis compound phase, which further comprises distilling under reduced pressure to obtain one or more distillation fractions comprising the glycolysis compound and one or more distillation fractions comprising by-products.

[0094] In one or more embodiments, the reaction temperature for the predetermined reaction time of 30 minutes to 150 minutes to form the refolding mixture is 180°C to 190°C.

[0095] In one or more embodiments, the reaction temperature for the predetermined reaction time of 30 minutes to 150 minutes to form the refolding mixture is between 170°C and 190°C.

[0096] In one or more embodiments, the reaction temperature for the predetermined reaction time of 30 minutes to a minimum of 150 minutes to form the regenerating mixture is between 180°C and 185°C.

[0097] In one or more embodiments, the reaction temperature for the predetermined reaction time of 30 minutes to 120 minutes to form the refolding mixture is 170°C to 190°C.

[0098] In one or more embodiments, the reaction temperature for the predetermined reaction time of 30 minutes to 120 minutes to form the refolding mixture is 180°C to 190°C.

[0099] In one or more embodiments, the reaction temperature for the predetermined reaction time of 30 minutes to a minimum of 120 minutes to form the refolding mixture is 180°C to 185°C.

[0100] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 120 minutes to form the refolding mixture is between 170°C and 190°C.

[0101] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 120 minutes to form the refolding mixture is 180°C to 190°C.

[0102] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to a minimum of 120 minutes to form the regenerating mixture is between 180°C and 185°C.

[0103] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 100 minutes to form the refolding mixture is 170°C to 190°C.

[0104] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 100 minutes to form the refolding mixture is 180°C to 190°C.

[0105] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to a minimum of 100 minutes to form the refolding mixture is 180°C to 185°C.

[0106] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 to 80 minutes to form the refolding mixture is between 170°C and 190°C.

[0107] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 to 80 minutes to form the regenerating mixture is 180°C to 190°C.

[0108] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to a minimum of 80 minutes to form the refolding mixture is 180°C to 185°C.

[0109] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 240 minutes to form the regenerated mixture is between 180°C and 220°C.

[0110] In one or more embodiments, the reaction temperature for the predetermined reaction time of 90 to 220 minutes to prepare the regeneration mixture is 180°C to 220°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 120 to 200 minutes to prepare the regeneration mixture is 180°C to 220°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 150 to 200 minutes to prepare the regeneration mixture is 180°C to 220°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 170 to 190 minutes to prepare the regeneration mixture is 180°C to 220°C.

[0111] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 240 minutes to form the regenerating mixture is between 190°C and 220°C.

[0112] In one or more embodiments, the reaction temperature for the predetermined reaction time of 90 to 220 minutes to prepare the regeneration mixture is 190°C to 220°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 120 to 200 minutes to prepare the regeneration mixture is 190°C to 220°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 150 to 200 minutes to prepare the regeneration mixture is 190°C to 220°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 170 to 190 minutes to prepare the regeneration mixture is 190°C to 220°C.

[0113] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 240 minutes to form the refolding mixture is between 190°C and 210°C.

[0114] In one or more embodiments, the reaction temperature for the predetermined reaction time of 90 to 220 minutes to prepare the regeneration mixture is 190°C to 210°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 120 to 200 minutes to prepare the regeneration mixture is 190°C to 210°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 150 to 200 minutes to prepare the regeneration mixture is 190°C to 210°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 170 to 190 minutes to prepare the regeneration mixture is 190°C to 210°C.

[0115] In one or more embodiments, the reaction temperature for the predetermined reaction time of 60 minutes to 240 minutes to form the refolding mixture is between 195°C and 205°C.

[0116] In one or more embodiments, the reaction temperature for the predetermined reaction time of 90 to 220 minutes to prepare the regeneration mixture is 195°C to 205°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 120 to 200 minutes to prepare the regeneration mixture is 195°C to 205°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 150 to 200 minutes to prepare the regeneration mixture is 195°C to 205°C. In one or more embodiments, the reaction temperature for the predetermined reaction time of 170 to 190 minutes to prepare the regeneration mixture is 195°C to 205°C.

[0117] In one or more embodiments, the glycolysis compound was heated to 170-200°C under stirring and reflux for 30 minutes. After heating, polyurethane was added to the heated glycolysis compound. This polyurethane was shredded polyurethane. After adding the shredded polyurethane, the solution was heated for an additional 15 minutes, followed by the addition of zinc acetate. After the addition of zinc acetate, the solution was heated for an additional 60 minutes, then the heating device was removed and the solution was instead cooled to 120°C while still stirring the solution. When the solution reached a temperature of 120°C, stirring of the solution was stopped and the solution was transferred to a separatory funnel, which allowed it to separate into three phases over a period of four hours. These three phases were then separated into three different containers for further use.

[0118] When describing the embodiments, not all possible combinations and permutations of the embodiments are explicitly described. Nevertheless, the mere fact that certain measures are recited in mutually different dependent claims or described in different embodiments does not indicate that a combination of these measures cannot be used to advantage. The present invention envisages all possible combinations and permutations of the described embodiments. [Example]

[0119] Example The present invention is further illustrated by the following examples, which should not be construed as limiting the scope of protection. The features disclosed in the above description and in the following examples may be important for realizing the invention in diverse forms thereof, both separately or in any combination thereof.

[0120] Example 1 300 mL of glycolysis compound PEG 400 was heated to 185°C for 19 minutes under reflux using a reflux condenser and a mechanical stirrer (300 rpm). After 19 minutes of heating, 200 g of a polyurethane elastomer containing methylene diphenyl diisocyanate (MDI) and a polyether polyol, Shore A 55, was added to the heated PEG 400. The polyurethane elastomer was shredded polyurethane with an average shred size of 0.3 mm. Within 3 minutes of adding the shredded polyurethane, the solution temperature dropped to 143°C. The mixture was then heated to a set temperature of 185°C for an additional 12 minutes, after which 3 g of anhydrous zinc acetate was added to the solution. After the addition of the anhydrous zinc acetate, the solution was maintained at 185°C for an additional 60 minutes, and then the heating device was removed while still stirring the solution. The reaction mixture was then poured into a separatory funnel, which was allowed to separate into three phases at 50°C for 24 hours. These three phases were then separated into three different containers for further use.

[0121] Example 2 The three phases obtained in the experiment described in Example 1, namely, the polyol phase, the glycolysis compound phase, and the isocyanate derivative and aromatic dicarbamate phase, were recovered. The polyol phase was then used to obtain a new polyurethane elastomer by mixing the recycled polyol obtained in Example 1 with the unrecycled polyol and isocyanate in a vortex mixer for 30 seconds. The solution was then transferred to a heated aluminum mold with a narrow 3 mm opening, thereby obtaining a 3 mm thick polyurethane sheet. The aluminum mold was heated to 90°C, and the polyurethane sheet was cured in the aluminum mold for 10 minutes. It was then transferred to an oven, where it was further cured at 100°C for 16 hours.

[0122] Various weight ratios of recycled polyol and non-recycled polyol from Example 1 were mixed in a vortex mixer according to Table 1 below. The polyol and isocyanate contents were measured to achieve a total mass of 70 grams, and are also shown in Table 1.

[0123] [Table 1]

[0124] The ultimate tensile strength is measured according to ISO 37 / 1A / 20.

[0125] The ultimate tensile displacement is measured according to ISO 37 / 1A / 20.

[0126] The coefficient of friction (static) is measured according to ISO 15113.

[0127] Example 3 300 mL of glycolysis compound PEG 400 was heated to 180 or 200°C for 19 minutes under reflux using a reflux condenser under mechanical stirring (300 rpm). After 19 minutes of heating, a Shore A55 polyurethane elastomer containing methylene diphenyl diisocyanate (MDI) and a polyether polyol was added to the heated PEG 400. The polyurethane elastomer was added in weight amounts corresponding to a 1:1 or 1:2 ratio (polyurethane elastomer:glycolysis compound—e.g., 325 g of PEG 400 and 150 g of polyurethane elastomer would be a 1:2 ratio). This polyurethane elastomer was shredded polyurethane with an average shred size of 0.3 mm. The solution temperature decreased to 143°C within 3 minutes of adding the shredded polyurethane. The mixture was then heated to the set temperature of 180 or 200°C for an additional 12 minutes, after which 1 or 4 g of anhydrous zinc acetate was added to the solution. After the anhydrous zinc acetate was added, the solution was maintained at 180 or 200°C for an additional 60 or 180 minutes, and then the heating device was removed while still maintaining stirring of the solution. The reaction mixture was then cooled and poured into a separatory funnel, which was allowed to separate into three phases at 50°C for 24 hours. These three phases were then analyzed for further analysis and to determine the recycled polyol deviation yield. * The resulting solution was divided into three different containers for determination of β-glucan (see Table 2).

[0128] *The polyol deviation yield is calculated based on the theoretical polyol content of the polyurethane elastomer, which means that, for example, when 100 grams of polyol is present in the polyurethane elastomer, if the polyol deviation yield is close to 0, it means that 100 grams of said polyol is present in the upper polyol phase.

[0129] [Table 2]

[0130] Table 2 shows the results of the polyol deviation yield (%) based on five different variables: reaction temperature (°C), ratio, catalyst amount (g), reaction time (min), and atmosphere. Based on statistical analysis (not shown), it can be observed that while ratio, catalyst, and atmosphere all overlap with similar median values ​​(not statistically significant), there is no overlap in the case of reaction temperature and reaction time, as lower polyol deviation yields are obtained at 200°C and 180 min.

[0131] In particular, when a reaction temperature of 180°C is used, the polyol yield deviation is 51.85±27.74 wt% higher than when 200°C is used, while when a reaction time of 60 minutes is used, the polyol yield deviation is 40.66±27.74 wt% higher than when 180 minutes is used.

[0132] Finally, it can be observed that there is a positive synergy between reaction temperatures around 200° C. and reaction times around 180 minutes.

Claims

1. 1. A method for obtaining recycled polyol from a first polyurethane and using the polyol as a component in a second polyurethane, comprising: a. contacting the first polyurethane with a catalyst and a molar excess of a glycolysis compound to obtain a reaction mixture, wherein the glycolysis compound is selected from one or more long-chain glycols containing at least two hydroxyl groups and having a molecular weight of 180 to 1100 g / mol; b. reacting the reaction mixture of step a) at a reaction temperature of 170°C to 220°C for a predetermined reaction time of 30 minutes to 240 minutes to form a regenerated mixture; c. Separating the regenerated mixture of step b) into at least three immiscible phases to obtain at least a recovered polyol phase, a glycolysis compound phase, and a waste phase; d. using the recovered polyol phase as a polyol component in the process for producing the second polyurethane; wherein the glycolysis compound and the first polyurethane are selected such that the glycolysis compound has a higher density than the recycled polyol.

2. 10. The method of claim 1, wherein the glycolysis compound phase is reused as the glycolysis compound in another process to obtain recycled polyol.

3. 3. The method according to claim 1 or 2, wherein the glycolysis compound is selected from one or more polyethylene glycols, such as PEG 400, having a molecular weight of 380 to 420 g / mol.

4. 4. The method of any one of claims 1 to 3, wherein the separating step c) is by rotating the regenerated mixture at at least 3000-10000 rpm for a predetermined period of time, and / or by maintaining or heating the regenerated mixture to at least 30°C, such as at least 40°C, for a predetermined period of at least 15 minutes, and / or by allowing the regenerated mixture to stand for a predetermined period of at least 30 minutes.

5. 5. The method of any one of claims 1 to 4, wherein the recovered polyol phase is used directly as a polyol component in a process for producing new polyurethane.

6. 6. A method according to any one of claims 1 to 5, wherein the polyol phase is used in an amount of up to 60% by weight, for example 30 to 50% by weight, of the total amount of reaction mixture used to prepare the second polyurethane.

7. 7. The method of any one of claims 1 to 6, further comprising cooling the regenerated mixture before separating the regenerated mixture in step c), wherein the cooling is carried out at a temperature of from about 30°C to about 60°C, for example from about 40°C to about 50°C.

8. The method of any one of claims 1 to 7, wherein the first and second polyurethanes are substantially the same polyurethane.

9. A method according to any one of claims 1 to 8, wherein the catalyst is selected from metal acetates, such as zinc acetate.

10. The method of any one of claims 1 to 9, wherein the catalyst is at a concentration of 2 to 4% by weight relative to 100% by weight of the first polyurethane.

11. The method according to any one of claims 1 to 10, wherein the polyurethane and the glycolysis compound are mixed in a ratio of 1:1 to 1:

2.

12. 12. The process of any one of claims 1 to 11, wherein the reaction temperature is from 180°C to 220°C, such as from 190°C to 220°C, such as from 190°C to 210°C or such as from 195°C to 205°C.

13. 13. The method according to any one of claims 1 to 12, wherein the predetermined reaction time is between 60 and 240 minutes, such as between 90 and 220 minutes, for example between 120 and 200 minutes, such as between 150 and 200 minutes or such as between 170 and 190 minutes.

14. Step a) comprises: a1) providing said molar excess of said glycolysis compound; a2) adding said first polyurethane to said glycolysis compound to obtain a pre-reaction mixture; a3) adding said catalyst to said pre-reaction mixture of step a2) to obtain said reaction mixture; The method according to any one of claims 1 to 13, comprising:

15. 15. A polyurethane prepared from a polyol mixture and one or more isocyanates, the polyol mixture comprising at least 5 wt.% of recovered polyol phase obtained from the process for obtaining recycled polyol according to any one of claims 1 to 14, such as at least 10 wt.%, for example at least 15 wt.%, such as at least 20 wt.%, for example at least 25 wt.%, such as at least 30 wt.% or such as at least 35 wt.% of recovered polyol phase.

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