Solvent removal in process for recycling one or more polymers, such as polyurethanes, contained in solid material

Abstract

The present invention relates to a solvent-efficient process for recycling one or more polymers selected from the group consisting of polyurethanes, polyurethane ureas, polyisocyanurate and mixtures of two or more thereof, said one or more polymers being contained in a solid material W. The invention also relates to a solvent-efficient process for recycling one or more polymers selected from the group consisting of polyurethanes, polyurethane ureas, polyisocyanurate and mixtures of two or more thereof.

Description

[0001] The present invention relates to a solvent efficient method for recycling one or more polymers selected from the group consisting of polyurethanes, polyurethaneureas, polyisocyanurates and mixtures of two or more thereof, the one or more polymers being contained in a solid material W.

[0002] Polyurethanes belong to the class of polycondensation polymers. They are usually produced from one or more polyols and one or more di- or polyisocyanates.

[0003] In terms of sustainability, polyurethanes should be recycled as much as possible. In general, polyurethanes can be recycled in a variety of ways. One of the most interesting ways is to re-monomerize polyurethanes or polyurethane waste by recovering polyol and isocyanate components or corresponding precursors. For this purpose, the prior art proposes to cleave polyurethanes by, for example, hydrolysis, glycolysis, alcoholysis and aminolysis to form isocyanate derivatives (amines, carbamates, ureas) and polyols.

[0004] For example, WO 2008 / 014988 A1 relates to the re-cleavage of polyurethanes. Specifically, a method for the cleavage of polyurethanes and polyurethane ureas is described, in which the polymers are first reacted with gaseous or liquid aliphatic or cycloaliphatic secondary amines, and the secondary ureas formed are cleaved into isocyanates after removal together with hydrogen chloride. In addition, the polyols or polyamines also formed in the reaction are processed and purified.

[0005] One of the biggest challenges of prior art recycling methods is the separation of polyols from isocyanate derivatives, which is mainly based on phase decay. However, this may only be applicable to selected polyurethanes and may be prone to failure due to possible contamination in polyurethane waste. Therefore, prior art recycling methods are typically severely limited in their applicability.

[0006] Therefore, there is a need for an improved process for recycling polymers such as polyurethanes, polyurethaneureas and polyisocyanurates. It is therefore an object of the present invention to provide an improved process for recycling polymers such as polyurethanes, polyurethaneureas and polyisocyanurates, in particular for decomposing said polymers into monomers in order to produce new polymers.

[0007] Surprisingly, it has been found that the process of the present invention allows recycling of various polyurethanes, polyurethaneureas, polyisocyanurates from solid wastes such as end-of-life foams by decomposing the polymers which can then be used in different applications such as the production of new monomers. Furthermore, the process of the present invention allows a reduction in the total solvent consumption compared to known processes for recycling polymers, which reduction also allows a reduction in costs. Thus, the use of a solvent efficient process for recycling polymers such as polyurethanes, polyurethaneureas and polyisocyanurates allows a reduction in the CO2 footprint.

[0008] Therefore, the present invention relates to a solvent-efficient method for recycling one or more polymers selected from the group consisting of polyurethanes, polyurethaneureas, polyisocyanurates and mixtures of two or more thereof, said one or more polymers being contained in a solid material W, the method comprising

[0009] (i) preparing a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols, comprising:

[0010] (i.1) providing a solid material W comprising one or more polymers selected from the group consisting of polyurethane, polyurethaneurea, polyisocyanurate and a mixture of two or more thereof;

[0011] (i.2) In the reactor unit R A Introducing the solid material W provided in (i.1) and one or more primary amines as a first solvent to obtain a mixture;

[0012] (i.3) subjecting the mixture obtained according to (i.2) to R A subjecting the mixture M to aminolysis reaction conditions to obtain a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols and one or more primary amines;

[0013] (i.4) From R A removing the mixture M obtained according to (i.3);

[0014] (ii) feeding the second solvent S and the mixture M obtained according to (i) to an evaporation unit EU, from which a vapor mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L ;

[0015] (iii) from M obtained according to (ii) L Separating the one or more polyurea-containing compounds from the mixture to obtain a mixture U comprising the one or more polyurea-containing compounds and a mixture P comprising the one or more polyols;

[0016] (iv) subjecting the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds to a reaction unit R C subjecting the mixture to cleavage reaction conditions to obtain one or more corresponding polyamines or one or more corresponding polyisocyanates;

[0017] (v) in a purification unit PU from the M obtained according to (ii) VSeparating the one or more primary amines from the steam to obtain a vapor mixture A depleted in S and containing the one or more primary amines;

[0018] (vi) recycling at least a portion of A obtained from PU according to (v) to R in (i.2) A as the first solvent.

[0019] Preferably, the method further comprises, before (i), subjecting the solid material W to a pretreatment, more preferably a mechanical pretreatment, wherein the mechanical pretreatment more preferably comprises one or more of grinding, crushing, chopping and cutting, more preferably grinding or chopping the solid material W.

[0020] Preferably, the method further comprises, before (i), more preferably after subjecting the solid material W to a pretreatment as defined above, drying the solid material W, wherein the drying is more preferably carried out at a temperature in the range of 40°C to 100°C, more preferably in the range of 50°C to 85°C, and wherein the drying is more preferably carried out in a gas atmosphere comprising one or more of nitrogen and oxygen, more preferably in air.

[0021] Preferably, the water content of the solid material W, more preferably after drying as defined above, is below 1000 ppm-weight-%, below 100 ppm-weight-%.

[0022] Preferably, the solid material W is waste solid material.

[0023] Preferably, the waste material is end-of-life material, such as one or more of end-of-life foam, end-of-life flexible foam, end-of-life rigid foam, end-of-life dense elastomer and end-of-life dense duromer. In the context of the present invention, end-of-life material is material at the end of a product's life cycle.

[0024] Preferably, in addition to one or more polymers, the solid material W further comprises impurities, which may be one or more of glass, sand, wood, metal, paper, inorganic solids and polymers other than polyurethane, polyurethane urea, polyisocyanurate. The polymers other than polyurethane, polyurethane urea, polyisocyanurate may be, for example, one or more of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET) or polystyrene (PS).

[0025] Preferably, the solid material W is one or more of a powder, a foam block, a pellet, a granule and a flake, more preferably one or more of a powder, a pellet, a granule and a flake.

[0026] Preferably, the average particle size of the solid material W provided in (i) is between 10 -6 Up to 10 -1m, preferably within the range of 10 -6 Up to 10 -2 The average particle size is determined by laser diffraction or optical microscopy in the range of 100 to 200 m. The skilled person adjusts these methods to the particle size range. Therefore, particle sieve analysis can also be used to determine the average particle size.

[0027] Preferably, the one or more polymers contained in the solid material W are one or more polyurethanes, more preferably the one or more polyurethanes are thermosetting materials or elastomers.

[0028] According to the present invention, there is no particular limitation on the polyurethane of W used in the method of the present invention. However, preferably, the polyurethane of W is prepared by a process in which a polyisocyanate is reacted with a polyol in the presence of one or more catalysts as known in the art.

[0029] Suitable polyisocyanate components for the production of polyurethanes of W include any polyisocyanate known for the production of polyurethanes. These include aliphatic, alicyclic and aromatic difunctional or polyfunctional isocyanates known from the prior art, as well as any desired mixtures thereof. Examples are diphenylmethane 2,2'-, 2,4'- and 4,4'-diisocyanates, mixtures of monomeric diphenylmethane diisocyanates with diphenylmethane diisocyanate homologues having a greater number of rings (polymeric MDI), isophorone diisocyanate (IPDI) and its oligomers, toluene 2,4- and 2,6-diisocyanates (TDI), and mixtures of these, tetramethylene diisocyanate and its oligomers, hexamethylene diisocyanate (HDI) and its oligomers, naphthylene diisocyanate (NDI) and mixtures thereof.

[0030] Preference is given to toluene 2,4- and / or 2,6-diisocyanate (TDI) or mixtures thereof, monomeric diphenylmethane diisocyanate, and / or diphenylmethane diisocyanate homologues with a greater number of rings (polymeric MDI), and mixtures of these. Other possible isocyanates are mentioned, for example, in "Kunststoffhandbuch [Plastics handbook] [Plastics Handbook], Volume 7, Polyurethane [Polyurethanes] Polyurethane [Polyurethane]", Carl Hanser Verlag, 3rd edition, 1993, Chapters 3.2 and 3.3.2.

[0031] Suitable polyols for producing the polyurethane of W are selected from the group consisting of polyether polyols, polyester polyols, polyetherester polyols and mixtures thereof.

[0032] The polyether alcohols are produced, for example, from epoxides, such as propylene oxide and / or ethylene oxide, or from tetrahydrofuran and starting compounds which exhibit hydrogen activity, such as fatty alcohols, phenols, amines, carboxylic acids, water, or compounds based on natural substances, such as sucrose, sorbitol or mannitol, using catalysts. Mention may be made here of basic catalysts and double metal cyanide catalysts, as described, for example, in WO 2006 / 034800, EP 0090444, or WO 2005 / 090440.

[0033] Polyesterols are produced, for example, from aliphatic or aromatic dicarboxylic acids and polyols, polythioether polyols, polyesteramides, hydroxylated polyacetals, and / or hydroxylated aliphatic polycarbonates, preferably in the presence of an esterification catalyst. Other possible polyols are mentioned, for example, in "Kunststoffhandbuch [Plastics handbook] [Plastics Handbook], Volume 7, Polyurethane [Polyurethanes] Polyurethane [Polyurethane]", Carl Hanser Verlag, 3rd edition, 1993, Chapter 3.1.

[0034] Alternatively, preferably, the one or more polymers contained in the solid material W are one or more polyurethane ureas. According to the present invention, there are no particular restrictions on the polyurethane ureas used in the method of the present invention. However, preferably, the polyurethane urea of ​​W is prepared by a process in which a polyisocyanate is reacted with a polyol in the presence of a catalyst as is well known in the art. Suitable polyisocyanates and suitable polyols, preferably polyether polyols, are as defined above and are known in the art.

[0035] Alternatively, preferably, the one or more polymers contained in the solid material W are one or more polyisocyanurates. According to the present invention, there are no particular restrictions on the polyisocyanurates used in the method of the present invention. However, preferably, the polyisocyanurates of W are prepared by a method in which polyisocyanates react with polyols in the presence of at least one catalyst as known in the art. Suitable polyisocyanates are those listed above. Other possible isocyanates are, for example, mentioned in "Kunststoffhandbuch [Plastics handbook] [Plastics Handbook], Vol. 7, Polyurethane [Polyurethanes] Polyurethane [Polyurethane]", Carl Hanser Verlag, 1993, 3rd edition, Chapters 3.2 and 3.3.2. Preferably, polyisocyanates are toluene 2,4- and / or 2,6-diisocyanate (TDI) or mixtures thereof, monomeric diphenylmethane diisocyanate, and / or diphenylmethane diisocyanate homologues (polymer MDI) with more rings, and mixtures of these. Suitable polyols for producing the polyisocyanurates of W are those known in the art, for example those listed in "Kunststoffhandbuch [Plastics handbook] [Plastics Handbook], Volume 7, Polyurethane [Polyurethanes] Polyurethane [Polyurethane]", Carl Hanser Verlag, 3rd edition 1993, Chapters 3.2 and 3.3.2. Preferably, the polyols for producing the polyisocyanurates of W are polyester polyols, such as branched polyester polyols based on terephthalic acid and having an OH number of 245 mg KOH / g.

[0036] In the context of the present invention, it is also conceivable that as another alternative, the one or more polymers contained in the solid material W are preferably a mixture of one or more of polyurethanes, polyisocyanurates and polyurethaneureas.

[0037] Preferably, the reactor unit R A It comprises, more preferably consists of: one or more reactors, more preferably at least two reactors, more preferably two reactors, wherein preferably at least two reactors are arranged in parallel.

[0038] Preferably, each of the one or more reactors is a stirred reactor, preferably a stirred tank reactor.

[0039] Preferably, each of the one or more reactors is a heated reactor, an adiabatic reactor or an autoclave.

[0040] Preferably, the one or more primary amines used in (i.2) do not contain hydroxyl groups.

[0041] Preferably, the one or more primary amines used in (i.2) contain no hydroxyl groups and no aldehyde groups. More preferably, the one or more primary amines used in (i.2) contain no hydroxyl groups, no aldehyde groups and no ketone groups.

[0042] In other words, preferably, the atoms forming the one or more primary amines used in (i.2) are C, H and N.

[0043] Preferably, the one or more primary amines used as the first solvent in (i.2) are selected from the group consisting of aliphatic monoamines, aliphatic polyamines, aromatic monoamines, aromatic polyamines and mixtures of two or more thereof, more preferably selected from the group consisting of aliphatic monoamines, aliphatic polyamines, aromatic monoamines and mixtures of two or more thereof, more preferably selected from the group consisting of aliphatic monoamines, aromatic monoamines and mixtures of two of them.

[0044] More preferably, the one or more primary amines are of the formula H2NR 1 The aliphatic monoamines

[0045] Where R 1 Choose from (C3-C 25 ) alkyl, phenyl, (C7-C 25 )aralkyl and (C7-C 25 )alkylaryl group, preferably selected from (C3-C 20 ) alkyl, (C8-C 22 )aralkyl and (C8-C 22 )alkylaryl, more preferably selected from the group consisting of (C3-C 10 ) alkyl, phenyl, (C 10 -C 20 )aralkyl and (C 10 -C 20 ) alkylaryl. More preferably, the aliphatic monoamine is selected from the group consisting of n-butylamine, cyclohexylamine, n-octylamine, n-hexylamine, n-propylamine, n-dodecylamine, n-tridecylamine, n-octadecylamine and a mixture of two or more thereof, more preferably selected from the group consisting of n-butylamine, n-octylamine, n-hexylamine and n-propylamine, wherein more preferably the aliphatic monoamine is n-butylamine.

[0046] Alternatively, more preferably, the one or more primary amines are aromatic monoamines, wherein the aromatic monoamines are selected from the group consisting of aniline, toluidine, naphthylamine, and mixtures of two or more thereof, wherein the aromatic monoamine is more preferably aniline.

[0047] Alternatively, more preferably, the one or more primary amines are aliphatic polyamines, wherein the aliphatic polyamine is selected from the group consisting of hexamethylenediamine, ethylenediamine, propylenediamine (such as propane-1,3-diamine, propane-1,2-diamine), isophoronediamine, butanediamine (such as butane-1,4-diamine, butane-1,3-diamine), pentanediamine (such as pentane-1,5-diamine), diaminocyclohexane (such as 1,2-diaminocyclohexane) and a mixture of two or more thereof, more preferably selected from the group consisting of hexamethylenediamine, ethylenediamine, propylenediamine and butanediamine, more preferably selected from the group consisting of hexamethylenediamine, ethylenediamine and propylenediamine. More preferably, the aliphatic polyamine is selected from the group consisting of ethylenediamine and propylenediamine.

[0048] In the context of the present invention, all isomers of the above-mentioned aliphatic polyamines are envisaged. Preferably, the propylenediamine is propane-1,3-diamine or propane-1,2-diamine.

[0049] Alternatively, more preferably, the one or more primary amines are of the formula H2N-R 2 -NH2 aromatic polyamines,

[0050] Where R 2 Choose from (C3-C 25 ) alkylene, (C6-C 25 )aralkylene and (C6-C 25 )alkylene aryl group, preferably selected from the group consisting of (C8-C 22 ) alkylene, (C8-C 22 )aralkylene and (C8-C 22 ) alkylene aryl group, more preferably selected from the group consisting of (C 10 -C 20 ) alkylene, (C 10 -C 20 ) aralkylene and (C 10 -C 20 ) alkylene aryl group. More preferably, the aromatic polyamine is selected from the group consisting of diaminotoluene, phenylenediamine and diaminodiphenylmethane, more preferably selected from the group consisting of diaminotoluene, phenylenediamine and 4,4'-diaminodiphenylmethane, more preferably diaminotoluene, more preferably 2,4-diaminotoluene.

[0051] In the context of the present invention, more preferably, the one or more primary amines are aromatic monoamines or aliphatic monoamines. More preferably, the one or more primary amines used in (i.2) are aniline or n-butylamine.

[0052] Preferably, the introduction of R A The weight of the solid material W introduced in R AThe weight ratio of the one or more primary amines in the formula (I) is in the range of 1:100 to 1:1, more preferably in the range of 1:40 to 1:3, more preferably in the range of 1:10 to 1:5.

[0053] Preferably, the aminolysis reaction according to (i.3) is carried out at a temperature in the range of 50°C to 250°C, more preferably in the range of 80°C to 200°C, more preferably in the range of 100°C to 220°C, more preferably in the range of 140°C to 200°C.

[0054] Preferably, the aminolysis reaction according to (i.3) is carried out at a pressure in the range of 1.0 to 25.0 bar (absolute pressure), more preferably in the range of 1.0 to 20.0 bar (absolute pressure), more preferably in the range of 1.0 to 18.0 bar (absolute pressure).

[0055] Preferably, the aminolysis reaction according to (i.3) is carried out for a duration in the range of 1 to 600 min, more preferably in the range of 20 to 450 min, more preferably in the range of 60 to 300 min.

[0056] Preferably, at most 0.1 wt-%, more preferably 0 to 0.01 wt-%, more preferably 0 to 0.001 wt-% of the mixture M obtained according to (i) consists of polymers selected from the group consisting of polyurethanes, polyurethaneureas and polyisocyanurates.

[0057] In other words, it is preferred that the mixture M is substantially free, more preferably free of polymers selected from the group consisting of polyurethanes and polyisocyanurates, meaning substantially free, more preferably free of polyurethanes and polyisocyanurates. This is determined by analyzing the mixture M by IR spectroscopy: the mixture M has a relative humidity of 200-2400 cm -1 No NCO-stretching vibrations were present, which means that the reaction (aminolysis) was complete.

[0058] Preferably, the method further comprises, after (i.4) and before (ii), converting the R A The mixture M taken out from the solid-liquid separation unit is sent to obtain a liquid mixture M containing one or more polyurea-containing compounds and one or more polyols. SLS and solid mixtures containing impurities.

[0059] Preferably, the impurities are one or more of glass, sand, wood, metal, paper, inorganic solids and polymers other than polyurethane, polyurethane urea and polyisocyanurate. The polymers other than polyurethane, polyurethane urea and polyisocyanurate may be, for example, one or more of polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET) or polystyrene (PS).

[0060] Preferably, the solid-liquid separation unit is a filtration unit or a centrifuge, more preferably a filtration unit, more preferably a filter, more preferably a bag filter, a bag filter, a membrane filter, a candle filter, an agitated pressure filter, a vacuum belt filter, a plate and frame filter, or a suction filter.

[0061] Preferably, according to (i.4) from R A The mixture M taken out is sent to a solid-liquid separation unit at a temperature in the range of 50°C to 250°C, more preferably in the range of 80°C to 200°C, more preferably in the range of 100°C to 220°C, more preferably in the range of 140°C to 200°C.

[0062] Preferably, the solid-liquid separation is performed at a pressure in the range of 1.0 to 20.0 bar (absolute), more preferably in the range of 1.0 to 20.0 bar (absolute), more preferably in the range of 1.0 to 18.0 bar (absolute).

[0063] Preferably, (ii) comprises

[0064] The second solvent S and the liquid mixture M SLS sent to an evaporation unit EU from which a vapor mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L .

[0065] Preferably, S has a water content in the range of 0 to 1000 ppm, more preferably in the range of 0 to 500 ppm, more preferably in the range of 0 to 100 ppm. In the context of the present invention, the solvent is therefore preferably an anhydrous solvent.

[0066] Preferably, S used in (ii) is selected from the group consisting of hydrocarbons, ketones and ethers, more preferably selected from the group consisting of xylene, toluene, n-heptane, methyl ethyl ketone (MEK), dioxane, benzene, hept-2-one and a mixture of two or more thereof, more preferably selected from the group consisting of xylene, toluene, n-heptane, benzene and a mixture of two or more thereof, more preferably xylene or toluene or benzene.

[0067] Preferably, for (ii), the amount of S added is calculated based on the weight ratio of the second solvent S relative to the one or more polymers of W provided according to (i.1), which weight ratio is in the range of 0.1:1 to 50:1, more preferably in the range of 1:1 to 20:1, more preferably in the range of 1:1 to 15:1, more preferably in the range of 1:1 to 10:1.

[0068] Preferably, the evaporation unit EU used in (ii) is one or more of a reactor equipped with a filter, a fractional distillation column and a flash drum, more preferably a reactor equipped with a filter, more preferably a stirred tank reactor equipped with a filter.

[0069] Preferably, the evaporation in the EU according to (ii) is carried out under a pressure difference, which is the difference between the pressure before the evaporation unit and the pressure at the evaporation unit, which is in the range of 0 to 30 bar (absolute pressure), more preferably in the range of 0.1 to 25 bar (absolute pressure), more preferably in the range of 0.2 to 20 bar (absolute pressure).

[0070] Preferably, the liquid mixture M L Contains liquid based mixture M L At most 10 wt-%, more preferably at most 8 wt-%, more preferably at most 5 wt-% of one or more primary amines by weight.

[0071] Preferably, (iii) comprises

[0072] (iii.1) adding a solvent, more preferably S, to the liquid mixture M obtained according to (ii) L allowing the one or more polyurea-containing compounds to precipitate to obtain a mixture comprising the one or more precipitated polyurea-containing compounds;

[0073] (iii.2) passing the mixture comprising the one or more precipitated polyurea-containing compounds obtained according to (iii.1) through a solid-liquid separation unit SLU to obtain a liquid mixture P comprising the one or more polyols and a solid mixture U comprising the one or more polyurea-containing compounds.

[0074] Preferably, the present invention relates to a solvent efficient method for recycling one or more polymers selected from the group consisting of polyurethanes, polyurethaneureas, polyisocyanurates and mixtures of two or more thereof, said one or more polymers being contained in a solid material W, the method comprising

[0075] (i) preparing a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols, comprising:

[0076] (i.1) providing a solid material W comprising one or more polymers selected from the group consisting of polyurethane, polyurethaneurea, polyisocyanurate and a mixture of two or more thereof;

[0077] (i.2) In the reactor unit R A Introducing the solid material W provided in (i.1) and one or more primary amines as a first solvent to obtain a mixture;

[0078] (i.3) subjecting the mixture obtained according to (i.2) to R A subjecting the mixture M to aminolysis reaction conditions to obtain a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols and one or more primary amines;

[0079] (i.4) From R A removing the mixture M obtained according to (i.3);

[0080] (ii) feeding the second solvent S and the mixture M obtained according to (i) to an evaporation unit EU, from which a vapor mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L ;

[0081] (iii) from M obtained according to (ii) L The one or more polyurea-containing compounds are separated from the mixture, wherein (iii) comprises

[0082] (iii.1) adding a solvent, more preferably S, to the liquid mixture M obtained according to (ii) L allowing the one or more polyurea-containing compounds to precipitate to obtain a mixture comprising the one or more precipitated polyurea-containing compounds;

[0083] (iii.2) passing the mixture comprising the one or more precipitated polyurea-containing compounds obtained according to (iii.1) through a solid-liquid separation unit SLU to obtain a liquid mixture P comprising the one or more polyols and a solid mixture U comprising the one or more polyurea-containing compounds;

[0084] (iv) subjecting the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds to a reaction unit R C subjecting the mixture to cleavage reaction conditions to obtain one or more corresponding polyamines or one or more corresponding polyisocyanates;

[0085] (v) in a purification unit PU from the M obtained according to (ii) V Separating the one or more primary amines from the steam to obtain a vapor mixture A depleted in S and containing the one or more primary amines;

[0086] (vi) recycling at least a portion of A obtained from PU according to (v) to R in (i.2) AMore preferably, the present invention relates to a solvent-efficient method for recycling one or more polymers selected from the group consisting of polyurethane, polyurethane urea, polyisocyanurate and mixtures of two or more thereof, the one or more polymers being contained in a solid material W, the method comprising

[0087] (i) preparing a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols, comprising:

[0088] (i.1) providing a solid material W comprising one or more polymers selected from the group consisting of polyurethane, polyurethaneurea, polyisocyanurate and a mixture of two or more thereof;

[0089] (i.2) In the reactor unit R A introducing the solid material W provided in (i.1) and one or more primary amines as a first solvent to obtain a mixture, wherein the atoms forming the one or more primary amines are C, H and N;

[0090] (i.3) subjecting the mixture obtained according to (i.2) to R A subjecting the mixture M to aminolysis reaction conditions to obtain a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols and one or more primary amines;

[0091] (i.4) From R A removing the mixture M obtained according to (i.3);

[0092] (ii) feeding a second solvent S and the mixture M obtained according to (i), wherein S has a water content in the range of 0 to 1000 ppm, more preferably in the range of 0 to 500 ppm, more preferably in the range of 0 to 100 ppm, to an evaporation unit EU, from which a vapour mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L ;

[0093] (iii) from M obtained according to (ii) L The one or more polyurea-containing compounds are separated from the mixture, wherein (iii) comprises

[0094] (iii.1) adding a solvent, more preferably S, to the liquid mixture M obtained according to (ii) L allowing the one or more polyurea-containing compounds to precipitate to obtain a mixture comprising the one or more precipitated polyurea-containing compounds;

[0095] (iii.2) passing the mixture comprising the one or more precipitated polyurea-containing compounds obtained according to (iii.1) through a solid-liquid separation unit SLU to obtain a liquid mixture P comprising the one or more polyols and a solid mixture U comprising the one or more polyurea-containing compounds;

[0096] (iv) subjecting the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds to a reaction unit R C subjecting the mixture to cleavage reaction conditions to obtain one or more corresponding polyamines or one or more corresponding polyisocyanates;

[0097] (v) in a purification unit PU from the M obtained according to (ii) V Separating the one or more primary amines from the steam to obtain a vapor mixture A depleted in S and containing the one or more primary amines;

[0098] (vi) recycling at least a portion of A obtained from PU according to (v) to R in (i.2) A as the first solvent.

[0099] In the context of the present invention, preferably, the solvent used in (iii.1) is selected from the group consisting of hydrocarbons, ketones and ethers, more preferably selected from the group consisting of xylene, toluene, n-heptane, methyl ethyl ketone (MEK), dioxane, benzene, hept-2-one and a mixture of two or more thereof, preferably selected from the group consisting of xylene, toluene, n-heptane, benzene and a mixture of two or more thereof, more preferably xylene or toluene or benzene.

[0100] Preferably, the solvent used in (iii) is the same as the solvent used in (ii), ie S.

[0101] Preferably, for (iii.1), the amount of solvent added is calculated based on the weight ratio of the solvent relative to the one or more polymers of W provided according to (i.1), which weight ratio is in the range of 0.1:1 to 50:1, more preferably in the range of 1:1 to 20:1, more preferably in the range of 1:1 to 15:1, and more preferably in the range of 1:1 to 10:1.

[0102] Preferably, the solid-liquid separation unit SLU in (iii.2) is a filter.

[0103] Preferably, at most 0.1 wt.-%, preferably 0 to 0.01 wt.-%, more preferably 0 to 0.001 wt.-%, of the mixture U consists of polyols.

[0104] In other words, it is preferred that the mixture U contains essentially no, more preferably no, polyols. This can be achieved, for example, by 13 C_NMR or HPLC.

[0105] Preferably, the process further comprises sending the mixture P comprising the one or more polyols obtained according to (iii.2) into a storage tank T4.

[0106] In the context of the present invention, the one or more polyols obtained as described above can be used for every conceivable use in industrial and consumer applications, including but not limited to polyurethane compounds, which in turn can be used for uses including but not limited to the following:

[0107] - Foam cushioning, e.g. for furniture, bedding and packaging

[0108] - Rigid foam insulation, e.g. for buildings and refrigeration

[0109] -Flexible foams, e.g. for upholstery, mattresses, footwear and seals

[0110] - Elastomers, e.g. for automotive and industrial parts such as suspension bushings, gaskets and seals

[0111] - Adhesives, sealants and coatings

[0112] -Rollers and drive belts, e.g. for conveyors, power transmissions and agricultural equipment

[0113] -Medical devices and implants, such as prosthetic and artificial heart valves

[0114] -Fibers, nonwovens and textiles

[0115] -Paints, coatings and inks

[0116] -Electronic components such as housings, gaskets and vibration dampers.

[0117] Preferably, the process further comprises, after (iii) and before (iv), washing the mixture U obtained according to (ii) on the SLU with a solvent, more preferably the same solvent as used in (iii.1), more preferably S. Preferably, the solvent is selected from the group consisting of hydrocarbons, ketones and ethers, more preferably selected from the group consisting of benzene, xylene, toluene, n-heptane, methyl ethyl ketone (MEK), dioxane, hept-2-one and mixtures of two or more thereof, preferably selected from the group consisting of xylene, toluene, n-heptane, benzene and mixtures of two or more thereof, more preferably benzene, xylene or toluene.

[0118] Preferably, the solvent has a water content in the range of 0 to 1000 ppm, more preferably in the range of 0 to 500 ppm, more preferably in the range of 0 to 100 ppm. In the context of the present invention, the solvent is therefore preferably an anhydrous solvent.

[0119] Preferably, the ratio of the weight of the solvent relative to the weight of the solid mixture U is in the range of 0.01:1 to 100:1, more preferably in the range of 0.1:1 to 10:1, more preferably in the range of 1:1 to 5:1.

[0120] Preferably, the method further comprises sending the filtrate obtained after washing U into a storage tank T4.

[0121] Preferably, the reactor unit R C It comprises one or more reactors, more preferably at least two reactors, more preferably in the range of 2 to 5 reactors, more preferably two reactors, and at least two reactors are more preferably arranged in parallel.

[0122] Preferably, R C is one or more of an evaporation unit EU and a solid-liquid separation unit SLU, preferably an evaporation unit EU and a solid-liquid separation unit SLU. Thus, preferably, (ii), (iv) and (v) are carried out in the same unit, which is more preferably a stirred tank reactor equipped with a filter. This configuration is possible if it is a batch process.

[0123] Alternatively, it is preferred that R C , EU and SLU are three unique units, among which EU is located upstream of SLU, which is located upstream of Rc.

[0124] Preferably, the cleavage reaction conditions according to (iv) are hydrolysis reaction conditions.

[0125] Preferably, (iv) comprises

[0126] Mixing water with the mixture U obtained according to (iii) comprising one or more polyurea-containing compounds in R C The method comprises mixing a polyamine with water, wherein the weight ratio of water to the one or more polyurea-containing compounds is in the range of 1:1 to 50:1, more preferably in the range of 5:1 to 20:1, more preferably in the range of 10:1 to 18:1, to obtain one or more corresponding polyamines.

[0127] Preferably, the hydrolysis is carried out at a temperature in the range of 150°C to 350°C, more preferably in the range of 210°C to 290°C, more preferably in the range of 230°C to 270°C.

[0128] Preferably, the hydrolysis is carried out for a duration in the range of 0.1 to 15 h, more preferably in the range of 0.25 to 10 h, more preferably in the range of 0.5 to 8 h.

[0129] Preferably, the hydrolysis is carried out at a pressure in the range of 20 to 70 bar (absolute), more preferably in the range of 25 to 65 bar (absolute), more preferably in the range of 30 to 60 bar (absolute).

[0130] Alternatively, preferably, the cleavage reaction conditions according to (iv) are acidic cleavage conditions. More preferably, (iv) comprises

[0131] The Bronsted acid is mixed with a mixture U comprising one or more polyurea-containing compounds obtained according to (iii) in R C and mixing with a bromoacetate, wherein more preferably the Bronsted acid is selected from the group consisting of hydrochloric acid, sulfonic acid and a mixture thereof, to obtain one or more corresponding polyisocyanates.

[0132] In the context of the present invention, the one or more polyisocyanates obtained as described above can be used for every conceivable use in industrial and consumer applications, including but not limited to polyurethane compounds, which in turn can be used for uses including but not limited to the following:

[0133] - Foam cushioning, e.g. for furniture, bedding and packaging

[0134] - Rigid foam insulation, e.g. for buildings and refrigeration

[0135] -Flexible foams, e.g. for upholstery, mattresses, footwear and seals

[0136] - Elastomers, e.g. for automotive and industrial parts such as suspension bushings, gaskets and seals

[0137] - Adhesives, sealants and coatings

[0138] -Rollers and drive belts, e.g. for conveyors, power transmissions and agricultural equipment

[0139] -Medical devices and implants, such as prosthetic and artificial heart valves

[0140] -Fibers, nonwovens and textiles

[0141] -Paints, coatings and inks

[0142] -Electronic components such as housings, gaskets and vibration dampers.

[0143] Preferably, the sulfonic acid is one or more of methanesulfonic acid, toluenesulfonic acid and trifluoromethanesulfonic acid.

[0144] Alternatively, preferably, the cleavage reaction conditions according to (iv) are alkaline cleavage conditions. More preferably, (iv) comprises

[0145] The Brønsted base is mixed with a solid mixture U obtained according to (iii) comprising one or more polyurea-containing compounds in R C The Brønsted base is mixed with water, wherein the Brønsted base has a pH value in the range of 8 to 12 in water, to obtain a mixture comprising one or more corresponding polyisocyanates.

[0146] Examples of bases for the cleavage reaction are alkali metal hydroxides, alkaline earth metal hydroxides, 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU), 1,4-diazabicyclo[2.2.2]octane (DABCO), triethylamine and primary amines as defined above for the aminolysis reaction.

[0147] Preferably, (iv) comprises

[0148] (iv.1) subjecting the mixture U comprising the one or more polyurea-containing compounds obtained according to (iii) to cleavage reaction conditions, more preferably hydrolysis reaction conditions, to obtain a mixture comprising one or more corresponding polyamines;

[0149] (iv.2) passing the mixture obtained according to (iv.1) through an evaporation unit EU1, obtaining from EU1 a vapor mixture M comprising water and at least a portion of the one or more primary amines V1 , and a liquid mixture M comprising the one or more polyamines EU1 ;

[0150] (iv.3) making the vapor mixture M obtained according to (iv.2) V1 Passing through a heat exchanger for condensation, obtaining a liquid mixture comprising water and at least a portion of the one or more primary amines, more preferably sending said obtained liquid mixture to a tank unit or a stripping column for removing carbon dioxide;

[0151] (iv.4) feeding the liquid mixture obtained according to (iv.3) to the PU used according to (v) to obtain a water-depleted vapor mixture comprising the one or more primary amines;

[0152] (iv.5) recycling at least a portion of the vapor mixture obtained from the PU according to (iv.4) to R in (i.2) A as the first solvent.

[0153] Preferably, the evaporation unit EU1 used in (iv.2) is one or more of a flash tank and a stripping column, more preferably a flash tank or a stripping column.

[0154] Preferably, the method further comprises

[0155] The liquid mixture M comprising the one or more polyamines obtained according to (iv.2)EU1 feeding a heat exchanger and introducing the mixture obtained into a decanter D, obtaining a lower phase comprising the one or more polyamines and an upper phase comprising water and at least a portion of the one or more primary amines;

[0156] More preferably, the upper phase is passed through a compressor and subsequently through the purification unit PU, more preferably PU2 as defined below.

[0157] Preferably, the method further comprises

[0158] introducing the lower phase into a purification unit PUA, more preferably into a distillation column, obtaining a liquid mixture comprising the one or more polyamines, wherein more preferably 99 to 100 wt-%, more preferably 99.5 to 100 wt-%, more preferably 99.9 to 100 wt-% of said mixture consists of the one or more polyamines, and obtaining a vaporous mixture comprising at least a portion of the one or more primary amines;

[0159] More preferably, the vapour mixture is introduced into a PU, more preferably PU2 as defined below.

[0160] Preferably, before (v), the method further comprises: V Stored in tank T3.

[0161] Preferably, the purification unit PU comprises a first purification subunit PU1 and a second purification subunit PU2, more preferably, PU1 and PU2 are subunits connected in series.

[0162] Preferably, the purification subunit PU1 is a distillation column. Preferably, the purification subunit PU2 is a distillation column.

[0163] Preferably, (v) comprises

[0164] (v.1) The M obtained according to (ii) V Introducing into PU1, obtaining a vapor mixture A1 comprising the one or more primary amines and a liquid mixture comprising S;

[0165] (v.2) introducing the vapor mixture A1 obtained according to (v.1) into PU2 to obtain a vapor mixture A comprising the one or more primary amines, wherein the concentration of the primary amines in A is greater than the concentration of the primary amines in A1.

[0166] Preferably, the method further comprises

[0167] The liquid mixture comprising S obtained according to (v.1) is stored in tank T2 and then recycled and used as solvent in (ii) and / or (iii.1), more preferably in (ii) and (iii.1).

[0168] Preferably, (iv) comprises

[0169] (iv.1) subjecting the mixture U comprising the one or more polyurea-containing compounds obtained according to (iii) to cleavage reaction conditions to obtain a mixture comprising one or more corresponding polyamines;

[0170] (iv.2) feeding the mixture obtained according to (iv.1) to an evaporation unit EU1, from which a vapor mixture M comprising water and at least a portion of the one or more primary amines is obtained V1 , and a liquid mixture comprising the one or more polyamines;

[0171] (iv.3) making the vapor mixture M obtained according to (iv.2) V1 obtaining, by means of a heat exchanger for condensation, a liquid mixture comprising water and at least a portion of the one or more primary amines, preferably sending said obtained liquid mixture to a tank unit or a stripping column for removing carbon dioxide;

[0172] (iv.4) feeding the liquid mixture obtained according to (iv.3) to the PU2 used according to (v) to obtain a water-depleted vapor mixture comprising the one or more primary amines;

[0173] (iv.5) recycling at least a portion of the vapor mixture obtained from PU2 according to (iv.4) to R in (i.2) A as the first solvent.

[0174] Preferably, the method further comprises

[0175] The mixture P obtained according to (iii) is sent to a purification unit PUP to separate the one or more polyols from the liquid mixture P, obtaining a mixture comprising the one or more polyols, reduced by at least a portion of compounds other than polyols.

[0176] Alternatively, preferably, (iv) comprises

[0177] The liquid mixture P obtained according to (ii) is sent to a purification unit PUP to obtain a liquid mixture comprising one or more polyols, reduced by at least a portion of the solvent S, and a vapor mixture V comprising at least a portion of S. S Preferably, the purification unit PUP comprises a distillation column, more preferably a distillation column.

[0178] More preferably, (iv) further comprises

[0179] The vapor mixture V comprising at least a portion of the solvent S and water Ssent to the purification unit PU1 to obtain a liquid mixture containing the solvent;

[0180] The liquid mixture obtained is introduced into tank T2, more preferably before being used as S in (ii.1) and / or (ii.2).

[0181] Preferably, the process is a semi-batch process.

[0182] The present invention is further illustrated by the following groups of embodiments and the combination of embodiments obtained by the dependencies and back-references as shown. In particular, it should be noted that in each case where a series of embodiments is mentioned, for example, in the context of a term such as "a method as described in any one of embodiments 1 to 4", each embodiment in this series is intended to be clearly disclosed to the technician, that is, the wording of this term should be understood by the technician as synonymous with "a method as described in any one of embodiments 1, 2, 3 and 4". In addition, it should be clearly pointed out that the following group of embodiments represents a suitable structural part of the general description of the preferred aspects of the present invention, and therefore appropriately supports but does not represent the claims of the present invention.

[0183] 1. A solvent-efficient method for recycling one or more polymers selected from the group consisting of polyurethanes, polyurethaneureas, polyisocyanurates, and mixtures of two or more thereof, said one or more polymers being contained in a solid material W, the method comprising

[0184] (i) preparing a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols, comprising:

[0185] (i.1) providing a solid material W comprising one or more polymers selected from the group consisting of polyurethane, polyurethaneurea, polyisocyanurate and a mixture of two or more thereof;

[0186] (i.2) In the reactor unit R A Introducing the solid material W provided in (i.1) and one or more primary amines as a first solvent to obtain a mixture;

[0187] (i.3) subjecting the mixture obtained according to (i.2) to R A subjecting the mixture M to aminolysis reaction conditions to obtain a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols and one or more primary amines;

[0188] (i.4) From R A removing the mixture M obtained according to (i.3);

[0189] (ii) feeding the second solvent S and the mixture M obtained according to (i) to an evaporation unit EU, from which a vapor mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L ;

[0190] (iii) from M obtained according to (ii) L Separating the one or more polyurea-containing compounds from the mixture to obtain a mixture U comprising the one or more polyurea-containing compounds and a mixture P comprising the one or more polyols;

[0191] (iv) subjecting the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds to a reaction unit R C subjecting the mixture to cleavage reaction conditions to obtain one or more corresponding polyamines or one or more corresponding polyisocyanates;

[0192] (v) in a purification unit PU from the M obtained according to (ii) V Separating the one or more primary amines from the steam to obtain a vapor mixture A depleted in S and containing the one or more primary amines;

[0193] (vi) recycling at least a portion of A obtained from PU according to (v) to R in (i.2) A as the first solvent.

[0194] 2. The method as described in Example 1 further comprises, before (i), subjecting the solid material W to pretreatment, preferably mechanical pretreatment, wherein the mechanical pretreatment preferably comprises grinding, crushing, chopping and cutting, preferably grinding or chopping the solid material W. One or more.

[0195] 3. The method as described in Example 1 or 2 further comprises, before (i), preferably after subjecting the solid material W to the pretreatment as defined in Example 2, drying the solid material W, wherein the drying is preferably carried out at a temperature in the range of 40°C to 100°C, more preferably in the range of 50°C to 85°C, and wherein the drying is more preferably carried out in a gas atmosphere comprising one or more of nitrogen and oxygen, more preferably in air.

[0196] 4. The method of any one of embodiments 1 to 3, wherein the solid material W is waste solid material.

[0197] 5. The method of any one of embodiments 1 to 4, wherein the one or more polymers contained in the solid material W are one or more polyurethanes, preferably the one or more polyurethanes are thermosetting materials or elastomers.

[0198] 6. The method of any one of embodiments 1 to 4, wherein the one or more polymers contained in the solid material W are one or more polyurethane ureas.

[0199] 7. The method of any one of embodiments 1 to 4, wherein the one or more polymers contained in the solid material W are one or more polyisocyanurates.

[0200] 8. The method according to any one of embodiments 1 to 7, wherein the reactor unit R A It comprises, preferably consists of: one or more reactors, preferably at least two reactors, more preferably two reactors, wherein preferably the at least two reactors are arranged in parallel.

[0201] 9. The method of embodiment 8, wherein each of the one or more reactors is a stirred reactor, preferably a stirred tank reactor.

[0202] 10. The method of embodiment 8 or 9, wherein each of the one or more reactors is a heated reactor, an adiabatic reactor, or an autoclave.

[0203] 11. The method of any one of embodiments 1 to 10, wherein the one or more primary amines used in (i.2) do not contain hydroxyl groups, preferably wherein the atoms forming the one or more primary amines used in (i.2) are C, H and N.

[0204] 12. A method as described in any one of Examples 1 to 11, wherein the one or more primary amines used as the first solvent in (i.2) are selected from the group consisting of aliphatic monoamines, aliphatic polyamines, aromatic monoamines, aromatic polyamines, and mixtures of two or more thereof, preferably selected from the group consisting of aliphatic monoamines, aliphatic polyamines, aromatic monoamines, and mixtures of two or more thereof, and more preferably selected from the group consisting of aliphatic monoamines, aromatic monoamines, and mixtures of two of them.

[0205] 13. The method of embodiment 12, wherein the one or more primary amines are of the formula H2NR 1 The aliphatic monoamines

[0206] Where R 1 Choose from (C3-C 25 ) alkyl, phenyl, (C7-C 25 )aralkyl and (C7-C 25 )alkylaryl group, preferably selected from (C3-C 20 ) alkyl, (C8-C 22 )aralkyl and (C8-C 22)alkylaryl, more preferably selected from the group consisting of (C3-C 10 ) alkyl, phenyl, (C 10 -C 20 )aralkyl and (C 10 -C 20 ) a group consisting of an alkylaryl group,

[0207] Wherein more preferably the aliphatic monoamine is selected from the group consisting of n-butylamine, cyclohexylamine, n-octylamine, n-hexylamine, n-propylamine, n-dodecylamine, n-tridecylamine, n-octadecylamine and a mixture of two or more thereof, more preferably selected from the group consisting of n-butylamine, n-octylamine, n-hexylamine and n-propylamine, wherein more preferably the aliphatic monoamine is n-butylamine.

[0208] 14. The method of embodiment 12, wherein the one or more primary amines are aromatic monoamines, wherein the aromatic monoamines are selected from the group consisting of aniline, toluidine, naphthylamine, and mixtures of two or more thereof, wherein the aromatic monoamine is preferably aniline.

[0209] 15. A method as described in Example 12, wherein the one or more primary amines are aliphatic polyamines, wherein the aliphatic polyamine is selected from the group consisting of hexamethylenediamine, ethylenediamine, propylenediamine, isophoronediamine, butanediamine, pentamethylenediamine, diaminocyclohexane and a mixture of two or more thereof, more preferably selected from the group consisting of hexamethylenediamine, ethylenediamine, propylenediamine and butanediamine, more preferably selected from the group consisting of hexamethylenediamine, ethylenediamine and propylenediamine; wherein the aliphatic polyamine is more preferably selected from the group consisting of ethylenediamine and propylenediamine.

[0210] 16. The method of embodiment 12, wherein the one or more primary amines are of the formula H2N-R 2 -NH2 aromatic polyamines,

[0211] Where R 2 Choose from (C3-C 25 ) alkylene, (C6-C 25 )aralkylene and (C6-C 25 )alkylene aryl group, preferably selected from the group consisting of (C8-C 22 ) alkylene, (C8-C 22 )aralkylene and (C8-C 22 ) alkylene aryl group, more preferably selected from the group consisting of (C 10 -C 20 ) alkylene, (C 10 -C 20 ) aralkylene and (C 10 -C 20 ) a group consisting of alkylene aryl groups,

[0212] Among them, the aromatic polyamine is more preferably selected from the group consisting of diaminotoluene, phenylenediamine and diaminodiphenylmethane, more preferably selected from the group consisting of diaminotoluene, phenylenediamine and 4,4'-diaminodiphenylmethane, more preferably diaminotoluene, and more preferably 2,4-diaminotoluene.

[0213] 17. The method of any one of embodiments 1 to 16, wherein R A The weight of the solid material W in R A The ratio by weight of the one or more primary amines in the formula (I) is in the range of 1:100 to 1:1, preferably in the range of 1:40 to 1:3, more preferably in the range of 1:10 to 1:5.

[0214] 18. A method as described in any one of Examples 1 to 17, wherein the aminolysis reaction according to (i.3) is carried out at a temperature in the range of 50°C to 250°C, preferably in the range of 80°C to 200°C, more preferably in the range of 100°C to 220°C, more preferably in the range of 140°C to 200°C.

[0215] 19. A method as described in any one of embodiments 1 to 18, wherein the aminolysis reaction according to (i.3) is carried out at a pressure in the range of 1.0 to 25.0 bar (absolute pressure), preferably in the range of 1.0 to 20.0 bar (absolute pressure), and more preferably in the range of 1.0 to 18.0 bar (absolute pressure).

[0216] 20. The method of any one of embodiments 1 to 19, wherein the aminolysis reaction according to (i.3) is carried out for a duration in the range of 1 to 600 min, preferably in the range of 20 to 450 min, more preferably in the range of 60 to 300 min.

[0217] 21. The process of any one of embodiments 1 to 20, wherein at most 0.1 wt.-%, preferably 0 to 0.01 wt.-%, more preferably 0 to 0.001 wt.-% of the mixture M obtained according to (i) consists of a polymer selected from the group consisting of polyurethanes, polyurethane ureas and polyisocyanurates.

[0218] 22. The method of any one of embodiments 1 to 21, further comprising, after (i.4) and before (ii), converting the product obtained from R A The mixture M taken out from the solid-liquid separation unit is sent to obtain a liquid mixture M containing the one or more polyurea-containing compounds and the one or more polyols. SLS and solid mixtures containing impurities.

[0219] 23. The method of embodiment 22, wherein theA The mixture M taken out is sent to a solid-liquid separation unit at a temperature in the range of 50°C to 250°C, preferably in the range of 80°C to 200°C, more preferably in the range of 100°C to 220°C, and more preferably in the range of 140°C to 200°C.

[0220] 24. The method of embodiment 22 or 23, wherein (ii) comprises

[0221] The second solvent S and the liquid mixture M SLS sent to an evaporation unit EU from which a vapor mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L .

[0222] 25. A method as described in any one of embodiments 1 to 24, wherein S used in (ii) is selected from the group consisting of hydrocarbons, ketones and ethers, more preferably selected from the group consisting of xylene, toluene, n-heptane, methyl ethyl ketone (MEK), dioxane, benzene, hept-2-one and mixtures of two or more thereof, preferably selected from the group consisting of xylene, toluene, n-heptane, benzene and mixtures of two or more thereof, more preferably xylene or toluene or benzene; and / or wherein S has a water content in the range of 0 to 1000 ppm, preferably in the range of 0 to 500 ppm, more preferably in the range of 0 to 100 ppm.

[0223] 26. A method as described in any of embodiments 1 to 25, wherein for (ii), the amount of S added is calculated based on the weight ratio of the second solvent S to the one or more polymers W provided according to (i.1), and the weight ratio is in the range of 0.1:1 to 50:1, preferably in the range of 1:1 to 20:1, more preferably in the range of 1:1 to 15:1, and more preferably in the range of 1:1 to 10:1.

[0224] 27. The method of any one of embodiments 1 to 26, wherein the evaporation in EU according to (ii) is carried out under a pressure difference, the pressure difference being the difference between the pressure before the evaporation unit and the pressure at the evaporation unit, in the range of 0 to 30 bar (absolute), preferably in the range of 0.1 to 25 bar (absolute), more preferably in the range of 0.2 to 20 bar (absolute).

[0225] 28. The method of any one of embodiments 1 to 27, wherein the liquid mixture M L Contains a liquid mixture based on M LAt most 10 wt-%, preferably at most 8 wt-%, more preferably at most 5 wt-% of the one or more primary amines by weight.

[0226] 29. The method of any one of embodiments 1 to 28, wherein (iii) comprises

[0227] (iii.1) adding a solvent, preferably S, to the liquid mixture M obtained according to (ii) L allowing the one or more polyurea-containing compounds to precipitate to obtain a mixture comprising the one or more precipitated polyurea-containing compounds;

[0228] (iii.2) passing the mixture comprising the one or more precipitated polyurea-containing compounds obtained according to (iii.1) through a solid-liquid separation unit SLU to obtain a liquid mixture P comprising the one or more polyols and a solid mixture U comprising the one or more polyurea-containing compounds.

[0229] 30. A method as described in Example 29, wherein the solvent used in (iii.1) is selected from the group consisting of hydrocarbons, ketones and ethers, more preferably selected from the group consisting of xylene, toluene, n-heptane, methyl ethyl ketone (MEK), dioxane, benzene, hept-2-one and a mixture of two or more thereof, preferably selected from the group consisting of xylene, toluene, n-heptane, benzene and a mixture of two or more thereof, more preferably xylene or toluene or benzene.

[0230] 31. A method as described in Example 29 or 30, wherein for (iii.1), the amount of the solvent added is calculated based on the weight ratio of the solvent relative to the one or more polymers of W provided according to (i.1), and the weight ratio is in the range of 0.1:1 to 50:1, preferably in the range of 1:1 to 20:1, more preferably in the range of 1:1 to 15:1, and more preferably in the range of 1:1 to 10:1.

[0231] 32. The process of any one of embodiments 1 to 31, wherein at most 0.1 wt-%, preferably 0 to 0.01 wt-%, more preferably 0 to 0.001 wt-% of the mixture U consists of polyols.

[0232] 33. The method of any one of embodiments 1 to 32, wherein the cleavage reaction conditions according to (iv) are hydrolysis reaction conditions.

[0233] 34. The method of embodiment 33, wherein (iv) comprises

[0234] water and the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds in R CThe method comprises mixing a polyamine with water, wherein the weight ratio of water to the one or more polyurea-containing compounds is in the range of 1:1 to 50:1, preferably in the range of 5:1 to 20:1, more preferably in the range of 10:1 to 18:1, to obtain one or more corresponding polyamines.

[0235] 35. The method of embodiment 33 or 34, wherein the hydrolysis is carried out at a temperature in the range of 150°C to 350°C, preferably in the range of 210°C to 290°C, more preferably in the range of 230°C to 270°C;

[0236] Therein preferably the hydrolysis is carried out for a duration in the range of 0.1 to 15 h, more preferably in the range of 0.25 to 10 h, more preferably in the range of 0.5 to 8 h.

[0237] 36. The process of any one of claims 33 to 35, wherein the hydrolysis is carried out at a pressure in the range of 20 to 70 bar (absolute), preferably in the range of 25 to 65 bar (absolute), more preferably in the range of 30 to 60 bar (absolute).

[0238] 37. The method of any one of embodiments 1 to 32, wherein the cleavage reaction conditions according to (iv) are acidic cleavage conditions.

[0239] 38. The method of embodiment 37, wherein (iv) comprises

[0240] The Bronsted acid is mixed with the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds in R C The Brønsted acid is preferably selected from the group consisting of hydrochloric acid, sulfonic acid and mixtures thereof to obtain one or more corresponding polyisocyanates.

[0241] 39. The method of any one of embodiments 1 to 38, insofar as embodiment 39 is dependent upon any one of embodiments 33 to 36, wherein (iv) comprises

[0242] (iv.1) subjecting the mixture U comprising the one or more polyurea-containing compounds obtained according to (iii) to cleavage reaction conditions, preferably hydrolysis reaction conditions, to obtain a mixture comprising one or more corresponding polyamines;

[0243] (iv.2) passing the mixture obtained according to (iv.1) through an evaporation unit EU1, obtaining from EU1 a vapor mixture M comprising water and at least a portion of the one or more primary amines V1 , and a liquid mixture M comprising the one or more polyamines EU1 ;

[0244] (iv.3) making the vapor mixture M obtained according to (iv.2) V1 obtaining, by means of a heat exchanger for condensation, a liquid mixture comprising water and at least a portion of the one or more primary amines, preferably sending said obtained liquid mixture to a tank unit or a stripping column for removing carbon dioxide;

[0245] (iv.4) passing the liquid mixture obtained according to (iv.3) through the PU used according to (v) to obtain a water-depleted vapor mixture comprising the one or more primary amines;

[0246] (iv.5) recycling at least a portion of the vapor mixture obtained from the PU according to (iv.4) to R in (i.2) A as the first solvent.

[0247] 40. The method of embodiment 39, wherein the evaporation unit EU1 used in (iv.2) is one or more of a flash tank and a stripping tower, preferably a flash tank or a stripping tower.

[0248] 41. The method of embodiment 39 or 40, further comprising

[0249] The liquid mixture M comprising the one or more polyamines obtained according to (iv.2) EU1 feeding a heat exchanger and introducing the mixture obtained into a decanter D, obtaining a lower phase comprising the one or more polyamines and an upper phase comprising water and at least a portion of the one or more primary amines;

[0250] The upper phase is preferably passed through a compressor and subsequently through the purification unit PU, more preferably PU2 as defined in Example 44.

[0251] 42. The method of embodiment 41, further comprising

[0252] introducing the lower phase into a purification unit PUA, preferably a distillation column, obtaining a liquid mixture comprising the one or more polyamines, wherein preferably 99 to 100 wt-%, more preferably 99.5 to 100 wt-%, more preferably 99.9 to 100 wt-% of said mixture consists of the one or more polyamines, and obtaining a vaporous mixture comprising at least a portion of the one or more primary amines;

[0253] Preferably the vapour mixture is introduced into PU, more preferably PU2 as defined in Example 44.

[0254] 43. The method of any one of embodiments 1 to 42, wherein, prior to (v), the method further comprises treating the M obtained according to (ii) V Stored in tank T3.

[0255] 44. The method of any one of embodiments 1 to 43, wherein the purification unit PU comprises a first purification subunit PU1 and a second purification subunit PU2, preferably PU1 and PU2 are subunits connected in series.

[0256] 45. The method of embodiment 44, wherein (v) comprises

[0257] (v.1) The M obtained according to (ii) V Introducing into PU1, obtaining a vapor mixture A1 comprising the one or more primary amines and a liquid mixture comprising S;

[0258] (v.2) introducing the vapor mixture A1 obtained according to (v.1) into PU2 to obtain a vapor mixture A comprising the one or more primary amines, wherein the concentration of the primary amines in A is greater than the concentration of the primary amines in A1.

[0259] 46. ​​The method of embodiment 45, further comprising

[0260] The liquid mixture comprising S obtained according to (v.1) is stored in tank T2 and then recycled and used as the solvent in (ii) and / or (iii.1), preferably in (ii) and (iii.1).

[0261] 47. The method of any one of embodiments 44 to 46, wherein (iv) comprises

[0262] (iv.1) subjecting the mixture U comprising the one or more polyurea-containing compounds obtained according to (iii) to cleavage reaction conditions to obtain a mixture comprising one or more corresponding polyamines;

[0263] (iv.2) feeding the mixture obtained according to (iv.1) to an evaporation unit EU1, from which a vapor mixture M comprising water and at least a portion of the one or more primary amines is obtained V1 , and a liquid mixture comprising the one or more polyamines;

[0264] (iv.3) making the vapor mixture M obtained according to (iv.2) V1 obtaining, by means of a heat exchanger for condensation, a liquid mixture comprising water and at least a portion of the one or more primary amines, preferably sending said obtained liquid mixture to a tank unit or a stripping column for removing carbon dioxide;

[0265] (iv.4) feeding the liquid mixture obtained according to (iv.3) to the PU2 used according to (v) to obtain a water-depleted vapor mixture comprising the one or more primary amines;

[0266] (iv.5) recycling at least a portion of the vapor mixture obtained from the PU according to (iv.4) to R in (i.2) A as the first solvent.

[0267] 48. The method of any one of embodiments 1 to 47, further comprising

[0268] The mixture P obtained according to (iii) is sent to a purification unit PUP to separate the one or more polyols from the liquid mixture P, obtaining a mixture comprising the one or more polyols, reduced by at least a portion of compounds other than polyols.

[0269] 49. The method of embodiment 48, wherein the purification unit PUP comprises a distillation column, more preferably a distillation column.

[0270] 50. The method of embodiment 46 or 47, insofar as embodiment 48 or 49 is dependent upon embodiment 24, wherein (iv) comprises

[0271] The liquid mixture P obtained according to (ii) is sent to a purification unit PUP to obtain a liquid mixture comprising one or more polyols, reduced by at least a portion of the solvent S, and a vapor mixture V comprising at least a portion of S. S .

[0272] 51. The method of embodiment 50, wherein (iv) further comprises

[0273] The vapor mixture V comprising at least a portion of the solvent S and water S sent to the purification unit PU1 to obtain a liquid mixture containing the solvent;

[0274] The liquid mixture obtained is introduced into tank T2, preferably before being used as S in (ii.1) and / or (ii.2).

[0275] 52. The method of any one of embodiments 1 to 51 which is a semi-batch method.

[0276] In the context of the present invention, polyurethane may be abbreviated as PUR or PU and refers to a class of polymers containing urethane (urethane) bonds. In addition, polyisocyanurate may be abbreviated as PIR and refers to polymers containing isocyanurate groups.

[0277] In the context of the present invention, urea is an organic compound of formula (RR'N)2CO, wherein R and R' are independently hydrogen or an organic residue, such as an alkyl residue or an aryl residue. Thus, this definition includes the specific compound ((H2N)2CO).

[0278] In addition, in the context of the present invention, PMDI refers to polymeric diphenylmethane diisocyanate, also referred to as industrial MDI, which is a mixture of methylene diphenyl isocyanate and homologous aromatic polyisocyanates. Therefore, it is a mixture of compounds with several (usually up to 6) phenylene groups, each of which has an isocyanate group.

[0279] Furthermore, in the context of the present invention, the term "polyurea-containing compound" refers to a compound, preferably a polymer, comprising at least two urea groups. In particular, in the context of the present invention, a polyurea-containing compound, preferably a polyurea-containing polymer, is preferably a compound derived from a polyurethane subjected to aminolysis.

[0280] In the context of the present invention, the term "primary amine" includes "primary monoamine" and "primary polyamine". As is well known in the art, primary amine refers to a compound having one or more amino groups, wherein the nitrogen atom is directly bonded to only one C atom.

[0281] In the context of the present invention, an alkyl group consists of carbon atoms and hydrogen atoms.

[0282] Furthermore, in the context of the present invention, the term "X is (or comprises) one or more of A, B and C", where X is a given feature and each of A, B and C represents a specific implementation of the feature, should be understood as disclosing that X is (or comprises) A, or B, or C, or A and B, or A and C, or B and C, or A and B and C. In this regard, it should be noted that a skilled person is able to convert the above abstract terms into specific examples, for example, where X is a chemical element and A, B and C are specific elements such as Li, Na and K, or X is a temperature and A, B and C are specific temperatures such as 10°C, 20°C and 30°C. In this regard, it is further noted that the skilled person is able to expand the above terms to less specific implementations of the features, such as “X is (or includes) one or more of A and B”, which discloses that X is (or includes) A, or B, or A and B, or to more specific implementations of the features, such as “X is (or includes) one or more of A, B, C, and D”, which discloses that X is A, or B, or C, or D, or A and B, or A and C, or A and D, or B and C, or B and D, or C and D, or A and B and C, or A and B and D, or B and C and D.

[0283] The present invention is further illustrated by the following examples.

[0284] Examples

[0285] Reference Example 1: Determination of FTIR spectrum

[0286] IR spectroscopy was performed to determine the conversion of the amination and aminolysis reactions.

[0287] For urea synthesis, at 2200-2400cm -1 The absence of NCO stretching vibrations indicates complete conversion of the corresponding isocyanate component (eg M20S).

[0288] For aminolysis, the urethane vibration (1700-1750 cm -1 ) is related to the conversion rate.

[0289] For the solubility test, the solubility of polyurea is characterized by the presence of characteristic carbonyl vibrations (1600-1700 cm -1 ). The area of ​​this vibration is related to the mass fraction of urea. In order to determine that the carbonyl vibration is characteristic of the solubility of urea, the IR instrument was calibrated with 1 wt-% solutions of dibutylamine and n-butylamine.

[0290] Reference Example 2: 13 C-NMR spectrum determination

[0291] In order to evaluate the purity of the synthesized urea, 13 C-NMR spectroscopy. The absence of peaks in the 50 to 80 ppm chemical shift range indicates the absence of polyols. The sample was dissolved in DMSO. As a reference standard, tetramethylsilane was used.

[0292] Reference Example 3: Appliance and structural foam and its composition

[0293] a) PUR appliance foam: Model foams were prepared by mixing 56 wt.% Lupranat M20S (Lupranat M20S is a commercial product of BASF with a typical NCO content of 31.5 g / 100 g and a viscosity of about 200 mPas at 25° C.) and 35% by weight of polyols (a mixture of polyols 1, 2 and 3) and additionally contains additives required for foaming, such as catalysts, surfactants, blowing agents.

[0294] b) PIR-structural foam: A model foam was prepared by mixing 71.4 wt.-% Lupranat M50S (Lupranat M50S is a commercial product of BASF, having a typical NCO content of 31.5 g / 100 g and a viscosity of about 550 mPas at 25° C.) and 18.4 wt.-% of polyol (polyol 4 is the main polyol), and further comprising additives required for foaming, such as catalysts, surfactants, blowing agents.

[0295] c) Polyols (see Figure 2 ):

[0296] Polyol 1 is a polyether-polyol synthesized from ortho-TDA (toluenediamine) as an initiator and PEO and PPO side chains, with an OH value of 160 mg KOH / g

[0297] Polyol 2 is a polyether-polyol synthesized from ortho-TDA (toluenediamine) as an initiator and PPO side chains; its OH-value is 400 mg KOH / g

[0298] Polyol 3 is a mixture of two polyether-polyols, one of which is synthesized from sorbitol as a starter and PPO side chains, and the other polyether-polyol is synthesized from glycerol as a starter and PPO side chains, and its OH-value is 430 mg KOH /

[0299] Polyol 4 is a slightly branched polyester polyol based on terephthalic acid and having an OH number of 245 mg KOH / g.

[0300] d) Surfactant: silicone oil;

[0301] e) Blowing agent: water, cyclopentane;

[0302] f) Catalyst: Lupragen N100, Lupragen N206, Lupragen N600 (all commercially available from BASF); These catalysts are generally tertiary amines of the general formula R1R2R3N. The fragments R1R2R3 are alkyl side chains with a chain length of 3 to 10 carbon atoms.

[0303] Reference Example 4: End-of-Life Foam

[0304] a) PUR - End of Life (EoL) foam: Foam powder obtained from refrigerator disassembly company (MDI based)

[0305] b) PU-flexible conventional foam from a mattress disassembly company, TDI based);

[0306] c) Polyols:

[0307]

[0308]

[0309] Reference Example 5: Solubility Test

[0310] Four different model systems were prepared for solubility testing of the corresponding resulting ureas in the presence of polyether / polyester-polyols.

[0311] 5.1. Synthesis of model systems

[0312] 5.1.a Polyurea derived from PMDI (using secondary amines)

[0313] In a 2L round flask, 50g of anhydrous dibutylamine (DBA) and 300g of monochlorobenzene (MCB) were mixed and stirred continuously. 17g of polymeric isocyanate (Lupranat) was added through a dropping funnel. A solution consisting of M20S (M20S, with a typical NCO content of 31.5 g / 100 g and a viscosity of about 200 mPas at 25° C.; BASF) and 281 g of monochlorobenzene was added dropwise over a period of 1 h. During the reaction, the reaction temperature was increased from 22.7° C. to 30.1° C. Afterwards, the reaction mixture was stirred overnight. The product obtained was analyzed using FTIR spectroscopy. At 2200-2400 cm -1 The absence of NCO stretching vibrations in the range indicated complete conversion of the isocyanate groups. Monochlorobenzene and excess dibutylamine were evaporated under vacuum and a highly viscous residue was obtained. The yield was 33.9 g, corresponding to 98%.

[0314] 5.1.b Polyurea derived from PMDI (using primary amines)

[0315] In a 2L round flask, 50g of anhydrous n-octylamine and 450g of monochlorobenzene were mixed and stirred continuously. 16g of polymeric isocyanate (Lupranat) was added through a dropping funnel. A solution consisting of M20S (M20S, with a typical NCO content of 31.5 g / 100 g and a viscosity of about 200 mPas at 25° C.; BASF) and 307 g of monochlorobenzene was added dropwise over a period of 1 h. During the reaction, the reaction temperature was increased from 22.7° C. to 50.8° C. Afterwards, the reaction mixture was stirred overnight. The product obtained was analyzed using FTIR spectroscopy. At 2200-2400 cm -1 The absence of NCO stretching vibrations in the range indicated complete conversion of the isocyanate groups. Monochlorobenzene and excess n-octylamine were evaporated under vacuum and a crystalline solid was obtained. The yield was 32.0 g, corresponding to 98%.

[0316] 5.1.c Polyurea derived from PMDI (using primary amines)

[0317] In a 2L round flask, 41g of anhydrous n-butylamine and 364g of monochlorobenzene were mixed and stirred continuously. 22g of polymeric isocyanate (Lupranat) was added through a dropping funnel. A solution consisting of M20S (M20S, with a typical NCO content of 31.5 g / 100 g and a viscosity of about 200 mPas at 25° C.; BASF) and 406 g of monochlorobenzene was added dropwise over a period of 1 h. During the reaction, the reaction temperature was increased from 21.7° C. to 31.4° C. Afterwards, the reaction mixture was stirred overnight. The product obtained was analyzed using FTIR spectroscopy. At 2200-2400 cm -1 The absence of NCO stretching vibrations in the range indicated complete conversion of the isocyanate groups. Monochlorobenzene and excess n-butylamine were evaporated under vacuum and a crystalline solid was obtained. The yield was 34.1 g, corresponding to 98%.

[0318] 5.1.d Polyureas derived from PMDI (using primary amines)

[0319] In a 2L round flask, 84g of anhydrous aniline and 762g of monochlorobenzene were mixed and stirred continuously. 36g of polymeric isocyanate (Lupranat) was added through a dropping funnel. A solution consisting of M20S (M20S, with a typical NCO content of 31.5 g / 100 g and a viscosity of about 200 mPas at 25° C.; BASF) and 652 g of monochlorobenzene was added dropwise over a period of 1 h. Afterwards, the reaction mixture was stirred overnight. The product obtained was analyzed using FTIR spectroscopy. At 2200-2400 cm -1 The absence of NCO stretching vibrations in the range indicated complete conversion of the isocyanate groups. Monochlorobenzene and excess aniline were evaporated under vacuum and a crystalline solid was obtained. The yield was 61.2 g, corresponding to 98%.

[0320] 5.1.e Polyureas derived from PMDI (using primary amines)

[0321] In a 2L round flask, 33.1g of anhydrous toluenediamine (TDA - aromatic polyamine) and 1100g of monochlorobenzene were mixed and stirred continuously. 3.6g of polymeric isocyanate (Lupranat) was added through a dropping funnel. A solution of 1,2-dichloro-1-(2-nitro-2-yl)-1-nitro-2-ol (1,2-dichloro ... -1 The absence of NCO stretching vibrations indicated complete conversion of the isocyanate groups. Monochlorobenzene and excess TDA were evaporated under vacuum and a crystalline solid (6.9 g) was obtained. The yield was 99%.

[0322] 5.1.f Polyurea derived from PMDI (using primary amines)

[0323] In a 2L round flask, 33g of anhydrous ethylenediamine (aliphatic polyamine) and 300g of monochlorobenzene were mixed and stirred continuously. 22g of polymeric isocyanate (Lupranat) was added through a dropping funnel. A solution of 1,4-dichlorobenzene (340 g) and 1,4-dichlorobenzene (3,4-dichlorobenzene) was added dropwise over 1 h. The reaction mixture was then stirred overnight. The product obtained was analyzed using FTIR spectroscopy. The FTIR spectrum was 2200-2400 cm -1 The absence of NCO stretching vibrations indicated complete conversion of the isocyanate groups. Monochlorobenzene and excess ethylenediamine were evaporated under vacuum and a crystalline solid (29.8 g) was obtained. The yield was 93%.

[0324] 5.2. Evaluation of polyurea solubility

[0325] 5.2.a Solubility screening

[0326] About 5 g of polyurea according to the corresponding model system, 2.5 g of a polyether-polyol mixture containing TDA, glycerol and sucrose-derived polyether-polyol and 25 g of the corresponding solvent were mixed at room temperature. After stirring for 90 min, the polyether-polyol was added and an IR sample was taken, diluted with chloroform and analyzed. At 1600-1700 cm -1 The carbonyl vibration area in the range 1.0 Å is related to the amount of urea dissolved. Detection limit < 1.0 wt-%. The results of the solubility tests of the model system prepared according to 1.ad are shown in Table 1 below.

[0327] Table 1 Solubility test results of the model system prepared according to 5.1.af.

[0328]

[0329]

[0330] Solubility test result (table 1) shows, the polyurea derived from the reaction of secondary amine (particularly dibutylamine) and PMDI is soluble in the solvent of test, and the polyurea derived from the reaction of primary amine and PMDI is actually insoluble.Especially, find that 9.1 weight-% of the polyurea derived from the reaction of dibutylamine and PMDI can be dissolved in toluene.Therefore, can expect that in dimethylbenzene, comparable solubility will be realized.In contrast, be less than 1.0 weight-% derived from primary amine, particularly the polyurea of ​​the reaction of n-octylamine, n-butylamine and aniline used in reference example 1.b-1.d can be dissolved in dimethylbenzene.Therefore, think that the polyurea of ​​these examples is insoluble in the solvent of test.

[0331] Example 1: Ammonolysis of PUR appliance foam with n-butylamine

[0332] 30 g of PUR-appliance foam according to reference example 3a) were ground using a coffee grinder and dried overnight at 100° C. in a nitrogen-purged atmosphere at atmospheric pressure. The dried foam and 150 g of n-butylamine were then charged into a stirred autoclave. The aminolysis reaction was carried out at 140° C. and about 5 bar (depending on the vapor pressure of n-butylamine) for 75 min. After the reaction, the mixture was cooled to room temperature and about 120 mL of n-butylamine was evaporated. 150 g of xylene were added to the resulting residue and the precipitation of the polyurea began. To complete the precipitation, the remaining n-butylamine was evaporated. Subsequently, the precipitated polyurea was filtered out and washed several times with xylene. With the help of 13 C-NMR- and IR-spectroscopy were used to record the conversion and purity of the precipitate. Figure 2 As can be seen from the IR spectrum shown, no characteristic urethane vibrations of polyurea were detected. The conversion rate was about 95% and only a small amount of ether groups were detected, such as from Figure 3 shown 13 The C-NMR spectrum showed that the purity was higher than 90%, and 16.1 g of the corresponding polyurea-containing compound was obtained (yield: 61%).

[0333] Example 2: Aniline hydrolysis of PUR appliance foam

[0334] 10 g of PUR-appliance foam according to reference example 3a) was ground using a coffee grinder and dried overnight at 100 ° C in a nitrogen-purged atmosphere at atmospheric pressure. Afterwards, the dried foam and 110 g of aniline were loaded into a 0.5 L round flask. The aminolysis reaction was carried out at 180 ° C under reflux for 1 h. During the aminolysis reaction, all compounds were completely dissolved in the aniline. After the reaction, the mixture was cooled to room temperature and the formed polyurea began to precipitate. After 12 h, the precipitate was filtered out. The solid was washed several times with xylene and dried overnight to obtain 3.5 g of polyurea, equivalent to 40%. Excess aniline was evaporated from the filtrate, and 250 g of xylene was added to the residue. The solution was stirred overnight. The newly formed precipitate was filtered, washed and dried to obtain 2.1 g of polyurea, equivalent to 24%. With the aid of 13C-NMR- and IR-spectroscopy, the aminolysis conversion and purity of the precipitate were recorded. The conversion rate was about 98% and no ether groups were detected. The purity was higher than 95%. 5.6 g of the corresponding polyurea-containing compound were obtained (yield: 64%).

[0335] Example 3: Ammonolysis of PUR-End-of-Life (EoL) Foam with n-Butylamine

[0336] 24 g of PUR-appliance end-of-life (EoL) foam according to reference example 4a) and 120 g of n-butylamine were charged into a stirred autoclave. The aminolysis reaction was carried out at 140° C. and about 5 bar (depending on the vapor pressure of n-butylamine) for 75 min. After the reaction, the mixture was cooled to room temperature. After the pressure was relaxed, the mixture was heated to 60° C. and filtered through a nylon filter to remove insoluble inorganic and organic impurities (m 杂质 =2.0 g). Then, about 120 mL of n-butylamine were evaporated. 150 g of xylene were added to the resulting residue and after a while the precipitation of the polyurea began. To complete the precipitation, the remaining n-butylamine was evaporated. Subsequently, the precipitated polyurea was filtered off and washed several times with xylene. 13 The precipitate was analyzed for conversion and purity of the aminolysis by C-NMR and IR spectroscopy. The conversion was about 98% and no ether groups were detected. The purity was above 95%. 8.6 g of the corresponding polyurea-containing compound were obtained.

[0337] Example 4: Ammonialysis of PUR-End-of-Life (EoL) Foam with Aniline

[0338] 25 g of PUR-appliance end-of-life (EoL) foam according to reference example 4a) and 250 g of aniline were added to a 0.5 L round flask. The aminolysis reaction was carried out at 180° C. under reflux for 1 h. During the aminolysis reaction, inorganic impurities precipitated. After the reaction, the mixture was filtered using a nylon filter and the filtrate was cooled to room temperature (m 杂质 =2.1 g). Then, the formed polyurea began to precipitate. After 12 h, the precipitate was filtered off. The solid was washed several times with xylene and dried overnight (m 聚脲，1 =10.3 g). Excess aniline was evaporated from the filtrate, and 250 g of xylene was added to the residue. The solution was stirred overnight. The resulting precipitate was filtered off, washed, and dried. (m 聚脲，2 =1.8 g, yield = 24%). 13 The precipitate was analyzed for conversion and purity by C-NMR- and IR-spectroscopy. The conversion was about 90% and no ether groups were detected. The purity was above 95%. 12.1 g of the corresponding polyurea-containing compound were obtained.

[0339] Example 5: Ammonolysis of PU soft foam with n-butylamine

[0340] 15 g of PU flexible foam according to reference example 4b) was mixed with liquid nitrogen, then ground using a coffee grinder and dried overnight at 100° C. in a nitrogen-purged atmosphere at atmospheric pressure. The dried foam and 150 g of n-butylamine were then added to a stirred autoclave. The aminolysis reaction was carried out at 140° C. and about 5 bar (depending on the vapor pressure of n-butylamine) for 75 min. After the reaction, the mixture was filtered under pressure at 140° C. to remove solid impurities. Then, the n-butylamine was evaporated under vacuum and the remaining residue was washed several times with n-heptane. Use 13 The conversion and purity of the precipitated polyurea were analyzed by C-NMR- and IR-spectroscopy. The conversion was about 90% and no ether groups were detected. The purity was above 80%. 6.1 g of the corresponding polyurea-containing compound were obtained.

[0341] Example 6: Decomposition of polyisocyanurate (PIR) structural foam using aniline

[0342] 15 g of dried and chopped PIR-structural foam according to reference example 3b) polyisocyanurate structural foam and 400 g of aniline were charged into a round flask equipped with a reflux condenser. The aminolysis reaction was carried out at 180°C for 60 min until the foam components were completely dissolved in the aniline. The mixture was cooled to room temperature and polyurea began to precipitate. The precipitated polyurea was filtered and the filtrate was concentrated by evaporation to remove the aniline. The remaining solid was also filtered out and washed several times with acetone. Use 13 The precipitate was analyzed for conversion and purity by C-NMR- and IR-spectroscopy. The conversion was about 90% and no ether groups were detected. The purity was above 95%. 12.2 g of the corresponding polyurea-containing compound were obtained (yield: 60%).

[0343] Example 7: Hydrolysis of polyurea-containing compounds (polymers) with water

[0344] 5.1 g of the polyurea obtained from Example 3 and 75 g of water were charged into a pressure autoclave. The mixture was heated to 250° C. and the temperature was maintained for 5 h, whereby the pressure was about 40 bar (absolute). After cooling, the mixture was analyzed using GC to assess the amount of PMDA. The purity was determined based on the area ratio of the GC peaks, and was therefore 85% (m 残余物 =4.3g). BRIEF DESCRIPTION OF THE DRAWINGS

[0345] Figure 1 is a schematic diagram of a production unit for a method according to a preferred embodiment of the present invention. The production unit comprises a zone Z, in which the aminolysis and cleavage reactions are carried out batchwise, said zone comprising, among other things, a reaction unit R Aand evaporation unit EU. The other components of this zone are defined in the present invention in the foregoing and are not shown in the figure. In addition, the production unit comprises four different storage tanks T1, T2, T3 and T4. T1 is a storage tank for one or more primary amines, preferably aniline or n-butylamine, T2 is a storage tank for solvent S, preferably xylene, T3 is a vapor mixture M containing solvent and primary amine V and T4 is a storage tank for the polyol formed in Z, said tank containing a mixture of polyol and S. At the beginning of the process, solid material W, preferably waste (foam), is introduced into R together with one or more primary amines from T1. A This allows obtaining a mixture M comprising one or more polyols and one or more polyurea-containing compounds. Further processing, such as adding a solvent S, preferably xylene, to the mixture M for subsequent flashing in EU. The vapor mixture M V The mixture containing one or more polyols and one or more polyurea-containing compounds is further precipitated by adding S, and the polyols and polyurea-containing compounds are separated. These steps are Figure 1 Furthermore, the polyurea-containing compound is subjected to cleavage reaction conditions, in this particularly preferred embodiment to hydrolysis, to obtain the corresponding polyamines. The polyamine mixture is removed from Z and introduced into the evaporating EU1 to obtain M V1 and M EU1 . M V1 and M EU1 As defined above. Preferably, M V1 Containing aniline or n-butylamine and M EU1 Contains one or more of polyamine, water, aniline or n-butylamine. Then, M V1 Through the heat exchanger for condensation and into the purification subunit PU2. A mixture A comprising, preferably consisting of, a primary amine (aniline or n-butylamine) is taken out of PU2 and introduced into T1. Thus, the primary amine is recycled. In addition, M EU1 By means of a heat exchanger and a decanter D, an upper phase comprising water and one or more polyamines and a lower phase comprising polyamines are obtained. The lower phase is then introduced into a purification unit PUA to obtain the final polyamine (product 1). The upper phase is optionally passed through a compressor and then enters PU2 to recover the primary amines as mixture A. As for the recycling of S, preferably xylene, the M after storage in T3 is VThe primary amines are recovered as mixture A by passing through purification unit PU1 and the fraction A1 rich in primary amines is further passed through PU2. The solvent, preferably xylene, is taken out at the bottom of PU1 and recycled to T2 for further use in the process. Finally, the mixture P containing polyols is stored in tank T4 and then passed through purification unit PUP to obtain the final polyols (product 2) and a mixture V containing solvent S, preferably xylene. S , and the mixture is further passed through PU1.

[0346] Figure 2 Shown are spectra of an IR analysis of a model foam and of a polyurea derived from PMDI (pMDI-urea) according to Example 1. On the abscissa, the wavenumber is in cm -1 , and on the ordinate, the absorbance is given in arbitrary units.

[0347] Figure 3 Shown is the 13C-NMR spectrum of the polyurea derived from PMDI according to Example 1. On the abscissa, the chemical shift is given in ppm and on the ordinate, the absorbance is given in arbitrary units.

[0348] References

[0349] - WO 2008 / 014988 A1

[0350] - Kunststoffhandbuch [Plastics handbook] [Plastics handbook], Volume 7, Polyurethane [Polyurethanes] Polyurethane [Polyurethane]", Carl Hanser Verlag, 3rd edition, 1993, Chapters 3.4.4 and 3.4.6 to 3.4.1

[0351] - WO 2006 / 034800

[0352] -EP 0090444

[0353] - WO 2005 / 090440

Claims

1. A solvent-efficient method for recycling one or more polymers selected from the group consisting of polyurethanes, polyurethaneureas, polyisocyanurates, and mixtures of two or more thereof, said one or more polymers being contained in a solid material W, the method comprising (i) preparing a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols, comprising: (i.1) providing a solid material W comprising one or more polymers selected from the group consisting of polyurethane, polyurethaneurea, polyisocyanurate and a mixture of two or more thereof; (i.2) In the reactor unit R A Introducing the solid material W provided in (i.1) and one or more primary amines as a first solvent to obtain a mixture; (i.3) subjecting the mixture obtained according to (i.2) to R A subjecting the mixture M to aminolysis reaction conditions to obtain a mixture M comprising one or more polyurea-containing compounds and further comprising one or more polyols and one or more primary amines; (i.4) From R A removing the mixture M obtained according to (i.3); (ii) feeding the second solvent S and the mixture M obtained according to (i) to an evaporation unit EU, from which a vapor mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L ; (iii) from M obtained according to (ii) L Separating the one or more polyurea-containing compounds from the mixture to obtain a mixture U comprising the one or more polyurea-containing compounds and a mixture P comprising the one or more polyols; (iv) subjecting the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds to a reaction unit R C subjecting the mixture to cleavage reaction conditions to obtain one or more corresponding polyamines or one or more corresponding polyisocyanates; (v) in a purification unit PU from the M obtained according to (ii) V Separating the one or more primary amines from the steam to obtain a vapor mixture A depleted in S and containing the one or more primary amines; (vi) recycling at least a portion of A obtained from PU according to (v) to R in (i.2) A as the first solvent.

2. The method of claim 1, wherein: The one or more primary amines used as the first solvent in (i.2) are selected from the group consisting of aliphatic monoamines, aliphatic polyamines, aromatic monoamines and mixtures of two or more thereof, preferably selected from the group consisting of aliphatic monoamines, aromatic monoamines and mixtures of two thereof.

3. The method of claim 2, wherein: The one or more primary amines are of the formula H2NR 1 The aliphatic monoamines Where R 1 Choose from (C3-C 25 ) alkyl, phenyl, (C7-C 25 )aralkyl and (C7-C 25 )alkylaryl group, preferably selected from (C3-C 20 ) alkyl, (C8-C 22 )aralkyl and (C8-C 22 )alkylaryl, more preferably selected from the group consisting of (C3-C 10 ) alkyl, phenyl, (C 10 -C 20 )aralkyl and (C 10 -C 20 ) a group consisting of an alkylaryl group, wherein more preferably the aliphatic monoamine is selected from the group consisting of n-butylamine, cyclohexylamine, n-octylamine, n-hexylamine, n-propylamine, n-dodecylamine, n-tridecylamine, n-octadecylamine and a mixture of two or more thereof, more preferably selected from the group consisting of n-butylamine, n-octylamine, n-hexylamine and n-propylamine, wherein more preferably the aliphatic monoamine is n-butylamine; or Wherein the one or more primary amines are aromatic monoamines, wherein the aromatic monoamine is selected from the group consisting of aniline, toluidine, naphthylamine and mixtures of two or more thereof, wherein the aromatic monoamine is preferably aniline.

4. The method according to any one of claims 1 to 3, wherein: The atoms forming the one or more primary amines used in (i.2) are C, H and N; Preferably the second solvent S used in (ii) has a water content in the range of 0 to 1000 ppm, more preferably in the range of 0 to 500 ppm, more preferably in the range of 0 to 100 ppm.

5. The method according to any one of claims 1 to 4, wherein: Introducing R A The weight of the solid material W in R A The ratio by weight of the one or more primary amines in the formula (I) is in the range of 1:100 to 1:1, preferably in the range of 1:40 to 1:3, more preferably in the range of 1:10 to 1:

5.

6. The method according to any one of claims 1 to 5, wherein: At most 0.1 wt-%, preferably 0 to 0.01 wt-%, more preferably 0 to 0.001 wt-% of the mixture M obtained according to (i) consists of polymers selected from the group consisting of polyurethanes, polyurethaneureas and polyisocyanurates.

7. The method of any one of claims 1 to 6, further comprising, after (i.4) and before (ii), converting the product obtained from R according to (i.4) to A The mixture M taken out from the solid-liquid separation unit is sent to obtain a liquid mixture M containing the one or more polyurea-containing compounds and the one or more polyols. SLS and solid mixtures containing impurities; Preferably, according to (i.4) A The mixture M taken out from the solid-liquid separation unit is sent to a solid-liquid separation unit at a temperature in the range of 50°C to 250°C, preferably in the range of 80°C to 200°C, more preferably in the range of 100°C to 220°C, more preferably in the range of 140°C to 200°C; Preferably (ii) includes The second solvent S and the liquid mixture M SLS sent to an evaporation unit EU from which a vapor mixture M comprising S and at least a portion of the one or more primary amines is obtained V , and a liquid mixture M comprising the one or more polyurea-containing compounds and the one or more polyols L .

8. The method according to any one of claims 1 to 7, wherein: The S used in (ii) is selected from the group consisting of hydrocarbons, ketones and ethers, more preferably selected from the group consisting of xylene, toluene, n-heptane, methyl ethyl ketone (MEK), dioxane, benzene, hept-2-one and mixtures of two or more thereof, preferably selected from the group consisting of xylene, toluene, n-heptane, benzene and mixtures of two or more thereof, more preferably xylene or toluene or benzene; and / or wherein S has a water content in the range of 0 to 1000 ppm, preferably in the range of 0 to 500 ppm, more preferably in the range of 0 to 100 ppm.

9. The method according to any one of claims 1 to 8, wherein: (iii) including (iii.1) adding a solvent, preferably S, to the liquid mixture M obtained according to (ii) L allowing the one or more polyurea-containing compounds to precipitate to obtain a mixture comprising the one or more precipitated polyurea-containing compounds; (iii.2) passing the mixture comprising the one or more precipitated polyurea-containing compounds obtained according to (iii.1) through a solid-liquid separation unit SLU to obtain a liquid mixture P comprising the one or more polyols and a solid mixture U comprising the one or more polyurea-containing compounds, wherein preferably at most 0.1 wt.-%, more preferably 0 to 0.01 wt.-%, more preferably 0 to 0.001 wt.-% of the mixture U consists of polyols; Wherein, in this method, preferably, the atoms forming the one or more primary amines used in (i.2) are C, H and N, and the second solvent S used in (ii), preferably (ii) and (iii) has a water content in the range of 0 to 1000 ppm, more preferably in the range of 0 to 500 ppm, more preferably in the range of 0 to 100 ppm.

10. The method according to any one of claims 1 to 9, wherein: The cleavage reaction conditions according to (iv) are hydrolysis reaction conditions.

11. The method of claim 10, wherein: (iv) including Mixing water with the mixture U obtained according to (iii) comprising the one or more polyurea-containing compounds in R C The method comprises mixing a polyamine with water, wherein the weight ratio of water to the one or more polyurea-containing compounds is in the range of 1:1 to 50:1, preferably in the range of 5:1 to 20:1, more preferably in the range of 10:1 to 18:1, to obtain one or more corresponding polyamines.

12. A method as claimed in any one of claims 1 to 11, insofar as claim 12 is dependent on claim 10 or 11, wherein (iv) including (iv.1) subjecting the mixture U comprising the one or more polyurea-containing compounds obtained according to (iii) to cleavage reaction conditions to obtain a mixture comprising one or more corresponding polyamines; (iv.2) feeding the mixture obtained according to (iv.1) to an evaporation unit EU1, from which a vapor mixture M comprising water and at least a portion of the one or more primary amines is obtained V1 , and a liquid mixture M comprising the one or more polyamines EU1 ; (iv.3) making the vapor mixture M obtained according to (iv.2) V1 obtaining, by means of a heat exchanger for condensation, a liquid mixture comprising water and at least a portion of the one or more primary amines, preferably sending said obtained liquid mixture to a tank unit or a stripping column for removing carbon dioxide; (iv.4) feeding the liquid mixture obtained according to (iv.3) to the PU used according to (v) to obtain a water-depleted vapor mixture comprising the one or more primary amines; (iv.5) recycling at least a portion of the vapor mixture obtained from the PU according to (iv.4) to R in (i.2) A as the first solvent.

13. The method of claim 12, further comprising The liquid mixture M comprising the one or more polyamines obtained according to (iv.2) EU1 feeding a heat exchanger and introducing the mixture obtained into a decanter D, obtaining a lower phase comprising the one or more polyamines and an upper phase comprising water and at least a portion of the one or more primary amines; The upper phase is preferably passed through a compressor and subsequently through the purification unit PU, more preferably PU2.

14. The method of claim 13, further comprising introducing the lower phase into a purification unit PUA, preferably a distillation column, obtaining a liquid mixture comprising the one or more polyamines, and obtaining a vapor mixture comprising at least a portion of the one or more primary amines; The vapor mixture is preferably introduced into the PU.

15. The method according to any one of claims 1 to 14, wherein: The purification unit PU comprises a first purification subunit PU1 and a second purification subunit PU2, preferably PU1 and PU2 are subunits connected in series.

16. The method of claim 15, wherein: (v) include (v.1) The M obtained according to (ii) V Introducing into PU1, obtaining a vapor mixture A1 comprising the one or more primary amines and a liquid mixture comprising S; (v.2) introducing the vapor mixture A1 obtained according to (v.1) into PU2 to obtain a vapor mixture A comprising the one or more primary amines; wherein (v) preferably further comprises The liquid mixture comprising S obtained according to (v.1) is stored in tank T2 and then recycled and used as the solvent in (ii) and / or (iii.1), more preferably in (ii) and (iii.1).

17. The method according to claim 15 or 16, wherein: (iv) including (iv.1) subjecting the mixture U comprising the one or more polyurea-containing compounds obtained according to (iii) to cleavage reaction conditions, preferably hydrolysis reaction conditions, to obtain a mixture comprising one or more corresponding polyamines; (iv.2) feeding the mixture obtained according to (iv.1) to an evaporation unit EU1, from which a vapor mixture M comprising water and at least a portion of the one or more primary amines is obtained V1 , and a liquid mixture comprising the one or more polyamines; (iv.3) making the vapor mixture M obtained according to (iv.2) V1 obtaining, by means of a heat exchanger for condensation, a liquid mixture comprising water and at least a portion of the one or more primary amines, preferably sending said obtained liquid mixture to a tank unit or a stripping column for removing carbon dioxide; (iv.4) feeding the liquid mixture obtained according to (iv.3) to PU2 used according to (v) to obtain a water-depleted vapor mixture A comprising the one or more primary amines; (iv.5) recycling at least a portion of the vapor mixture A obtained from PU according to (iv.4) to R in (i.2) A as the first solvent.

18. The method according to claim 16 or 17, wherein: (iv) including The liquid mixture P obtained according to (ii) is sent to a purification unit PUP to obtain a liquid mixture comprising one or more polyols, reduced by at least a portion of the solvent S, and a vapor mixture V comprising at least a portion of S. S ; Where (iv) further includes The vapor mixture V comprising at least a portion of the solvent S and water S sent to the purification unit PU1 to obtain a liquid mixture containing the solvent; The liquid mixture obtained is introduced into tank T2, preferably before being used as S in (ii.1) and / or (ii.2).

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