Depolymerization of polyisocyanurates using organic amine bases.

Abstract

The present invention relates to a process for the depolymerization of polyisocyanurates, in particular flexible and rigid polyisocyanurate foams, under mild conditions and low salt concentrations in the reaction mixture, which allows the valuable raw material of polyisocyanurates to be recovered in high yield and in good quality, i.e. in a quality that allows the use of the recycled raw material for the production of new polyurethanes, preferably polyurethane foams, or polyisocyanurates, preferably polyisocyanurate foams.

Description

[Technical Field]

[0001] The present invention relates to a process for the depolymerization of polyisocyanurates, in particular rigid polyisocyanurate foams, under mild conditions and low salt concentrations in the reaction mixture, which allows the valuable raw material of polyisocyanurates to be recovered in high yield and in good quality, i.e. in a quality that allows the use of the recycled raw material for the production of new chemicals, in particular new polyurethanes, preferably polyurethane foams or polyisocyanurates, preferably polyisocyanurate foams.

[0002] Polyurethanes are highly useful materials in the production of rigid and flexible foams, curable and microcellular elastomers, sealants, coatings, and adhesives. Their versatility, relatively low cost, and excellent properties have led to rapid growth of the polyurethane industry over the past 50 years. Currently, thousands of tons of polyurethane are produced annually worldwide, and various methods have been developed for chemical recycling of polyurethanes, including glycolysis, ammonolysis, aminolysis, acidolysis, and hydrolysis. These methods have in common that they cleave not only primarily urethane and urea groups, but also adjacent uretdione, carbodiimide, allophanate, and biuret groups.

[0003] Polyisocyanurate polymers differ from polyurethanes in that they contain isocyanurate groups, which, due to their ring structure, are more stable and less reactive than the functional groups that are cleaved during the chemical degradation of polyurethanes. Another difference between polyurethanes and polyisocyanurates is that polyurethanes are typically formed by the reaction of polyisocyanates with polyether polyols, whereas polyisocyanurates are obtained by the reaction of polyisocyanates with polyester polyols. In contrast to polyether groups, polyester groups are also cleaved during chemical degradation. Therefore, chemical methods developed and used for polyurethane recycling cannot be applied to polyisocyanurates.

[0004] Due to their higher chemical stability, polyisocyanurate foams are used as insulating boards in applications with particularly high demands on strength and flame retardancy. Those skilled in the art have long known that the high chemical stability of polyisocyanurates can be achieved by a large number of isocyanurate groups. The prevailing view in the art has been that in chemical recycling to recover raw materials for polyisocyanurate foams, especially in recycling processes based on hydrolysis, polyisocyanurate foams cannot be cut and the isocyanurate structure is largely preserved.

[0005] PNGribkova et al., "Degradation of a polyisocyanurate obtained by polycyclotrimerization of 4,4'-di-isocyanatodiphenylmethan," Polymer Science USSR, Vol. 22, pp. 299-304, compares the thermal decomposition, thermohydrolysis, and thermooxidative decomposition of isocyanurates. Under all conditions, homolytic decomposition and the formation of CO and H2 were observed, and it was found that high yields of raw materials could not be obtained. This confirms the prevailing view in the art that polyisocyanurates cannot be recycled into monomers that can be reused to produce new polyisocyanurates or polyurethanes.

[0006] As a result of the high chemical stability of polyisocyanurates, the development of chemical recycling methods to date has focused on polyurethane foams containing polyether polyols and having an isocyanate index of less than 150.

[0007] Resource scarcity, climate change, environmental impacts, and growing awareness of eco-friendly products are leading to an increased demand for new technologies to recycle plastics. This not only applies to polyurethanes, but also to polyisocyanurates, due to the large amounts present on the market.

[0008] There is therefore a strong need to provide an efficient and sustainable method for recycling polyisocyanurates in order to recover valuable raw materials in good yield and in good quality, i.e., preferably in a quality that allows their reuse as raw material for new polyurethanes and polyisocyanurates.

[0009] It was therefore an object of the present invention to provide a new process for the depolymerization of polyisocyanurates and a process for isolating and recovering the recycled hydrolysis product, preferably for reuse in producing chemicals. In particular, it is an object of the present invention to provide a new process for the depolymerization of polyisocyanurates, in which ring cleavage of the polyisocyanurates and urethane bond scission occurs.

[0010] A particular object of the present invention was to provide a process that can be carried out in standard equipment, i.e. a steel reactor.

[0011] Another particular problem of the present invention was to provide a process that can be carried out at lower temperatures and with good yields.

[0012] Another particular object of the present invention was to provide a method that allows for easy separation of the hydrolysis reactants and catalyst from the recovered raw materials. Separation should be possible under mild conditions.

[0013] Another particular object of the present invention was to provide a method with good yield and almost no side reactions. The method of the present invention should enable the cleavage of more than 85%, preferably more than 90%, particularly preferably more than 95%, and even more preferably 100% of the existing isocyanurate groups of the raw material. In this context, cleavage of isocyanurate groups means that the first bond of the isocyanurate group is cleaved and ring opening occurs.

[0014] The method of the present invention should be applicable to polyisocyanurates having a high isocyanate index of preferably 150 or more, preferably >150, more preferably >250.

[0015] A further specific problem to be solved by the present invention was to provide a method that allows for the recovery of polyols and / or amines and / or polyamines in a quality very close to that of the raw materials used to produce the polyisocyanurates that were subjected to hydrolysis. It should be possible to use a high proportion of the recovered polyols and / or amines and / or polyamines for the production of new chemicals, preferably isocyanates, polyurethanes, polyisocyanurates or polyureas, or for reuse in other applications, such as as epoxy curing agents or crosslinking agents for other polymers.

[0016] Another particular subject of the present invention was to provide a method that is advantageous compared to the prior art in terms of sustainability, in particular in terms of reducing or avoiding inorganic salt waste.

[0017] Further problems solved by the present invention but not mentioned above can be derived from the ensuing description, examples and claims.

[0018] The inventors have surprisingly discovered a method for hydrolyzing polyisocyanurates, which comprises the steps of: the polyisocyanurate is produced by reacting one or more polyols selected from the group consisting of polyester polyols, mixtures of polyester polyols, and mixtures of polyester polyols and polyether polyols with an excess of one or more isocyanates selected from the group consisting of organic isocyanates, mixtures of organic isocyanates, organic polyisocyanates, mixtures of organic polyisocyanates, and mixtures of organic isocyanate(s) and organic polyisocyanate(s); and contacting the polyisocyanurate with water in the presence of an organic amine base; one or more carboxylic acids containing two or more carboxylic acid groups per molecule and corresponding to the carboxylic acid(s) used to prepare the polyester polyol(s) used to prepare the polyisocyanurate; one or more polyols corresponding to the polyol(s) used to prepare the polyester polyol(s) used to prepare the polyisocyanurate; one or more organic amines and / or polyamines corresponding to the organic isocyanates or polyisocyanates used to prepare the polyisocyanurates; generating and The reaction mixture comprising the polyisocyanurate, water, and an organic amine base is a stirred homogeneous or heterogeneous mixture, preferably a solution, emulsion, or dispersion, or a combination thereof, during hydrolysis, the method comprising: It has been found that this method makes it possible to recover the raw materials used to prepare the polyisocyanurates, i.e., the carboxylic acid(s) and / or polyol(s) and / or organic amine(s) and / or organic polyamine(s), in high yield and purity.

[0019] The process of the present invention provides a particularly high cleavage rate of the existing isocyanurate groups, of more than 85%, preferably more than 90%, particularly preferably more than 95%, and even more preferably 100%, based on the initial amount of isocyanurate groups present in the raw material. The cleavage percentage is measured using TMS as a standard. 13 It can be determined by the disappearance of a signal at about 150 ppm in C NMR.

[0020] In addition to the ring cleavage of the existing isocyanurate groups, the method of the present invention also results in the cleavage of the polyester polyol used to prepare the polyisocyanurate into its raw materials, i.e., the corresponding carboxylic acid(s) and polyol(s) can be recovered. These reaction products can be easily separated from the resulting amine formed as a further reaction product. This will allow the recovery of recycled raw materials with high purity.

[0021] The recycled amine component of the isocyanurate, preferably the aromatic amine component, can be recovered in a purity that allows for, for example, phosgenation to polyisocyanates. The polyol(s) and carboxylic acid(s) are obtained in a purity that allows reuse for polyurethane or polyisocyanurate production or use in other applications such as polyesters. In particular, the recycled product can be used to produce fine-celled, uniform, and low-interference foams that meet all market requirements, for example, in terms of density, strength, insulation performance, or emissions. Advantageously, the recycled product of the present invention can be used to prepare new polyurethane or polyisocyanurate foams without adversely affecting the foam's properties.

[0022] The method of the present invention is particularly advantageous because it enables the recycling of polyester polyol-based polyisocyanurate foams having a high Isocyanate Index of 150 or greater, preferably >150, and more preferably >250, which was not previously possible.

[0023] A wide variety of organic amine bases that can be easily separated from the reaction products, i.e., the carboxylic acid, polyol, and polyamine components, preferably by distillation or extraction, can be used in the process of the present invention to effectively depolymerize the polyisocyanurate.

[0024] The organic amine bases used in the present invention are non-ionic organic bases, i.e., they are not in salt form, and therefore the amount of salt in the reaction solution that needs to be separated and disposed of is small.

[0025] The present inventors have surprisingly found that the organic amine base used in the present invention can be used without the addition of a phase transfer catalyst. This reduces the salt load of the reaction mixture and therefore reduces the effort required to separate and recover the reaction product. This further provides ecological and economic benefits due to the smaller amount of salt that must be disposed of.

[0026] Although the process of the present invention can be carried out without a phase transfer catalyst, the use of a phase transfer catalyst has been shown to accelerate the process in some systems compared to processes without a phase transfer catalyst. Phase transfer catalysts that can be added to the reaction mixture during hydrolysis are preferably selected from the group consisting of quaternary ammonium salts containing 6 to 30 carbon atoms and organic sulfonates containing at least 7 carbon atoms. Quaternary ammonium salts containing 6 to 30 carbon atoms are most preferred.

[0027] Depending on preference, lower salt loading or shorter reaction times are possible, making the process of the present invention very flexible. The inventors have found that when a phase transfer catalyst is used, it is preferable to use an ammonium cation. Ammonium cations with a low number of carbon atoms, i.e., less than 15, can be used as effectively as those with a higher number of carbon atoms, i.e., 15 to 30. The use of such a phase transfer catalyst allows for increased yields and increased flexibility regarding reaction temperatures.

[0028] The organic amine bases used in the present invention are non-corrosive, and therefore the process of the present invention can be carried out under less corrosive or non-corrosive conditions in standard equipment.

[0029] Further advantages will become apparent from the ensuing description, examples, claims and drawings.

[0030] MODE FOR CARRYING OUT THE INVENTION Before describing the present invention in more detail, some important terms are defined below.

[0031] As used in this specification, examples, and claims, the verb "to comprise" and its conjugations are used in an open-ended sense to mean that the items following the word are included, but items not specifically mentioned are not excluded. In its preferred embodiment, "comprising" includes "consisting of," which means that the items following the word "comprising" are included without additional items not specifically mentioned.

[0032] A reference to an element with the indefinite article "a" or "an" does not exclude the possibility that more than one element is present, unless the context clearly requires that one and only one element is present. Thus, the indefinite article "a" or "an" normally means "one or more."

[0033] The terms "catalyst" and "activator" are used interchangeably in this invention.

[0034] In the context of the present invention, polyurethane (PU) is understood to mean a product obtainable by the reaction of a polyisocyanate and a polyol, or a compound having an isocyanate-reactive group. Polyurethanes can be prepared from active hydrogen-containing polyethers and polyisocyanates. This type of polyurethane is well known and is described, for example, in Ulrich, "Urethane Polymers," in Encyclopedia of Chemical Technology, Vol. 23, pp. 576-608 (1983) and Backus et al., "Polyurethanes," in Encyclopedia of Polymer Science and Technology, Vol. 13, pp. 243-303 (1988).

[0035] In the context of the present invention, polyisocyanurate (PIR) is understood to mean a product obtainable by reacting a polyol component with an excess of a polyisocyanate component, the polyol component comprising a polyester polyol or a mixture of polyester and polyether polyols. Preferably, the isocyanate index of the PIR is 150 or greater. During the reaction of the polyol component with the excess of the polyisocyanate component, urethane structures are formed as a result of the reaction of isocyanates with compounds of the polyol component that have reactive hydrogen atoms, and through the reaction of the isocyanate groups themselves, there is the formation of isocyanurate structures or further structures resulting from the reaction of isocyanate groups with other groups, such as polyurethane groups. Polyisocyanurates have likewise been known for a long time and are described in the prior art.

[0036] Isocyanate Index as used herein should be understood as the molar ratio of polyisocyanate component to polyol component multiplied by 100, or in other words, the molar ratio of isocyanate groups to isocyanate-reactive groups multiplied by 100.

[0037] Preferably, rigid PIR foams are used in the present invention. "Rigid foam" is a well-established technical term. The well-known and fundamental difference between flexible and rigid foams is that flexible foams exhibit elastic behavior and therefore deformation is reversible. Rigid foams, on the other hand, are permanently deformed. Further information on rigid foams can also be found in "Kunststoff-handbuch, Band 7, Polyurethane", Carl Hanser Verlag, 3rd edition 1993, chapter 6. The terms "Hartfoam" or "rigid foam" are treated synonymously within the meaning of the present invention.

[0038] The method of the present invention is a method for hydrolyzing a polyisocyanurate, comprising the steps of: the polyisocyanurate is produced by reacting one or more polyols selected from the group consisting of polyester polyols, mixtures of polyester polyols, and mixtures of polyester polyols and polyether polyols with an excess of one or more isocyanates selected from the group consisting of organic isocyanates, mixtures of organic isocyanates, organic polyisocyanates, mixtures of organic polyisocyanates, and mixtures of organic isocyanate(s) and organic polyisocyanate(s); and contacting the polyisocyanurate with water in the presence of an organic amine base; one or more carboxylic acids containing two or more carboxylic acid groups per molecule and corresponding to the carboxylic acid(s) used to prepare the polyester polyol(s) used to prepare the polyisocyanurate; one or more polyols corresponding to the polyol(s) used to prepare the polyester polyol(s) used to prepare the polyisocyanurate; one or more organic amines and / or polyamines corresponding to the organic isocyanates or polyisocyanates used to prepare the polyisocyanurates; generating and The reaction mixture containing the polyisocyanurate, water, and organic amine base is a stirred homogeneous or heterogeneous mixture, preferably a solution, emulsion, dispersion, or a combination thereof, during hydrolysis. The method is characterized by:

[0039] Preferred PIR, more preferably PIR foam, even more preferably rigid PIR foam to be used in the method of the present invention is a) one or more polyols selected from the group consisting of polyester polyols or mixtures of polyester polyols or mixtures of polyester polyols and polyether polyols, and containing isocyanate-reactive groups selected from OH groups, SH groups, NH groups, NH groups and mixtures thereof, preferably OH groups, b) an excess of one or more isocyanates selected from the group consisting of organic isocyanates, mixtures of organic isocyanates, organic polyisocyanates, mixtures of organic polyisocyanates, and mixtures of organic isocyanate(s) and organic polyisocyanate(s); c) a catalyst that catalyzes the reaction of isocyanate-reactive groups with isocyanate groups and / or with each other, provided that at least one trimerization catalyst is included; d) optionally, a foam stabilizer e) optionally a propellant f) optionally further additives is prepared by reacting

[0040] Preferably, at least one polyol contains two or more isocyanate-reactive groups, preferably OH groups, selected from the group consisting of OH groups, SH groups, NH groups, NH groups, and mixtures thereof. More preferably, the polyol or mixture of polyols used in step a) has a total of an average of 1.8 to 8, preferably 1.9 to 5, more preferably 2 to 3, and most preferably 2, said isocyanate-reactive groups, and an average of 2 to 12, preferably 2 to 10, more preferably 2 to 6 carbon atoms. A functionality that is not an integer, such as 1.8, may result from the fact that at least one polyol having a higher functionality, such as 2 or more, is mixed with at least one polyol having a functionality of 1, for example.

[0041] The polyol(s) may contain ether and / or carbonate functionality, preferably polyether polyols or polyether carbonate polyols.

[0042] Preferred polyester polyols are based on esters of polybasic aliphatic or aromatic carboxylic acids or mixtures of aromatic and aliphatic carboxylic acids, in which carboxylic acid(s) having 2 to 12, preferably 4 to 10, and more preferably 6 to 10 carbon atoms per molecule are used in step a). Preferred aliphatic carboxylic acids are succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, and fumaric acid. Preferred aromatic carboxylic acids are phthalic acid, preferably (ortho)phthalic acid, isophthalic acid, terephthalic acid, and the isomeric naphthalenedicarboxylic acids. Polyester polyols are obtained by condensation of these polybasic carboxylic acids with polyols, i.e., polyhydric alcohols, preferably diols or triols having 2 to 12, more preferably 2 to 6 carbon atoms. Diols based on glycols and / or glycol ethers having a molecular weight of less than 180 g / mol, preferably less than 140 g / mol, are particularly preferred, with monoethylene glycol and / or diethylene glycol being most preferred. Preferably, the polyester polyol used to prepare the PIR contains an excess of polyhydric alcohol so that the polyhydric alcohol can also be present in an unbound form in the polyol component. Particularly preferred polyester polyols contain a high content of aromatic monomers. PIR made from such polyester polyols exhibit very high flame retardancy.

[0043] In a preferred embodiment, at least 90% by weight, preferably at least 95% by weight, more preferably at least 98% by weight of the polyol component used to prepare the polyisocyanurate is a polyester polyol having a hydroxyl number, measured according to DIN 53240, of 100 to 450 mg KOH / g, preferably 120 to 400 mg KOH / g, more preferably 140 to 350 mg KOH / g.

[0044] In addition to polyester polyols, one or more polyols selected from the group consisting of polyether polyols, polyether polycarbonate polyols, natural oil-based polyols (NOP; as described in WO 2005 / 033167, U.S. Patent Application Publication Nos. 2006 / 0293400, 2006 / 094227, 2004 / 096882, U.S. Patent Application Publication Nos. 2002 / 0103091, 2006 / 116456, and EP 1678232), filled polyols, and prepolymer-based polyols can be used in step a).

[0045] As the isocyanate b), any isocyanate or polyisocyanate containing at least two isocyanate groups can be used. Suitable isocyanates and polyisocyanates for the present invention are all organic isocyanates having two or more isocyanate groups. In general, aliphatic, cycloaliphatic, arylaliphatic, and mixtures thereof having two or more, preferably 2 to 4, isocyanate groups can be used. Such aromatic polyfunctional isocyanates are known per se. Preferably, alkylene diisocyanates having 4 to 12 carbon atoms in the alkylene group, such as dodecane 1,12-diisocyanate, 2-ethyltetramethylene 1,4-diisocyanate, 2-methylpentamethylene 1,5-diisocyanate, tetramethylene 1,4-diisocyanate, pentamethylene diisocyanate (PDI) and preferably hexamethylene 1,6-diisocyanate (HMDI), cyclohexane 1,3- and 1,4-diisocyanate and any mixtures of these isomers, 4,4'-methylenedicyclohexyl diisocyanate (H12MDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethylcyclohexane (isophorone diisocyanate), Cycloaliphatic diisocyanates, such as toluene 2,4- and 2,6-diisocyanate (IPDI for short), hexahydrotolylene 2,4- and 2,6-diisocyanate and the corresponding isomer mixtures, and preferably aromatic diisocyanates and polyisocyanates, such as toluene 2,4- and 2,6-diisocyanate (TDI) and the corresponding isomer mixtures, naphthalene diisocyanate, diethyltoluene diisocyanate, mixtures of diphenylmethane 4,4', 2,4'- and 2,2'-diisocyanate (MDI), and polyphenylpolymethylene polyisocyanate (PMDI, also known as polymeric and crude MDI) and their higher condensed analogues with an average functionality of 2 to 4, are used. A further example is a mixture of crude MDI with toluene diisocyanate (TDI). The organic diisocyanates and polyisocyanates can be used individually or in the form of their mixtures.It is also possible to use the corresponding "oligomers" of diisocyanates (IPDI trimers based on isocyanurates, biurets, and uretdione). Furthermore, prepolymers based on the above isocyanates can be used. It is also possible to use isocyanates modified by incorporating urethane, uretdione, isocyanurate, allophanate, and other groups, so-called modified isocyanates. Examples of particularly suitable isocyanates are listed, for example, in EP 1712578, EP 1161474, WO 00 / 58383, U.S. Patent Application Publication No. 2007 / 0072951, EP 1678232, and WO 2005 / 085310, which are incorporated by reference in their entirety.

[0046] Most preferred are the organic polyisocyanate isomers of toluene diisocyanate (toluene 2,4- and 2,6-diisocyanate (TDI) in pure form or as isomeric mixtures of varying composition), diphenylmethane 4,4'-diisocyanate (MDI), "crude MDI" or "polymeric MDI" (which includes the 4,4' isomer of MDI, but also the 2,4' and 2,2' isomers and products with three or more rings), and the two-ring products referred to as "pure MDI", which consist primarily of a mixture of the 2,4' and 4,4' isomers, and prepolymers derived therefrom. Examples of particularly suitable isocyanates are detailed, for example, in EP 1712578, EP 1161474, WO 00 / 58383, U.S. Patent Application Publication No. 2007 / 0072951, EP 1678232 and WO 2005 / 085310, which are hereby incorporated by reference in their entirety.

[0047] As catalyst c), any compound capable of accelerating the reaction of isocyanates with OH, NH or other isocyanate-reactive groups and with isocyanates themselves can be used.Here, conventional catalysts known in the art can be preferably used, including, for example, amines (cyclic, acyclic; monoamines, diamines, oligomers with one or more amino groups), ammonium compounds, organometallic compounds and metal salts, preferably salts of potassium, tin, iron, zinc or bismuth.It is also preferred to use a mixture of two or more of these catalysts.

[0048] Foam stabilizers (d) and their use in the production of PIR foams are known to those skilled in the art. As foam stabilizers, particularly surface-active compounds (surfactants) can be used. Although the use of foam stabilizers is optional, foam stabilizers are preferably used in the production of PIR foams. Foam stabilizers can be used to optimize the desired cell structure and foaming process. These compounds are well known in the art. Siloxanes are described, for example, in the following patent specifications, but their use is only described in classic PU foams (e.g., as molded foams, mattresses, insulating materials, building foams, etc.): CN 103665385, CN 103657518, CN 103055759, CN 103044687, US Patent Application Publication No. 2008 / 0125503, US Patent Application Publication No. 2015 / 0057384, EP 1520870, EP 1211279, EP 0867464, EP 0867465, EP 0275563. In addition to surface-active Si-containing compounds, Si-free surfactants can also be used. For example, EP 2295485 describes the use of lecithin, and US Patent 3746663 describes the use of vinylpyrrolidone-based structures as foam stabilizers, but only for the production of PU rigid foams. Further Si-free foam stabilizers are described, for example, in EP 2511328, DE 1020011007479, DE 3724716, EP 0734404, EP 1985642, DE 2244350 and US Patent 5236961.

[0049] The use of blowing agents to produce PIR foams is also well known in the art. It is possible to work with chemical and physical blowing agents. The choice of blowing agent strongly depends on the nature of the system. Depending on the amount of blowing agent used, foams with higher or lower densities are produced. Thus, a density of 5 kg / m is often used. 3 ~900kg / m 3 , preferably 5 to 350, more preferably 8 to 200 kg / m3 , especially 8 to 150 kg / m 3 Foams having densities of 0.1 to 1.0 can be prepared.

[0050] The preferred physical blowing agent used can be the corresponding compound with a suitable boiling point.Examples of blowing agents include liquefied CO2, nitrogen, air, volatile liquids, such as hydrocarbons with 3, 4 or 5 carbon atoms, preferably cyclo-, iso- and n-pentane, hydrofluorocarbons, preferably HFC245fa, HFC134a and HFC365mfc, hydrochlorofluorocarbons, preferably HCFC141b, hydrofluoroolefins (HFOs) or hydrohaloolefins, such as 1234ze, 1234yf, 1233zd(E) or 1336mzz, methyl formate, ketones, preferably acetone, ethers, preferably oxygen-containing compounds such as dimethoxymethane, or chlorinated hydrocarbons, preferably dichloromethane and 1,2-dichloroethane.

[0051] Likewise, it is possible to use chemical blowing agents, such as water or formic acid, which react with the NCO groups to liberate a gas, such as water or formic acid. As chemical blowing agents, one or more compounds can be used which react with the NCO groups by releasing a gas, such as water or formic acid, or which release a gas upon increasing the temperature during the reaction, such as sodium bicarbonate.

[0052] Optional additives f) which may be contained in the PIR include all substances known from the prior art and used in the production of polyisocyanurates, in particular polyisocyanurate foams, such as crosslinkers and chain extenders, stabilizers against oxidative degradation (known as antioxidants), flame retardants, surfactants, biocides, cell-refining additives, cell openers, solid fillers, antistatic additives, nucleating agents, thickeners, dyes, pigments, color pastes, fragrances and emulsifiers.

[0053] The process for producing rigid PIR foams can be carried out by known methods, for example by hand mixing, or preferably by means of a foaming machine. When the process is carried out by using a foaming machine, it is possible to use high-pressure or low-pressure machines.

[0054] Preferably, the polyisocyanurates used in the process of the present invention have an isocyanate index of 150 or greater, preferably >180, more preferably >250, and most preferably >250-500. Such polyisocyanurates are particularly stable and have very high chemical and / or flame resistance. Therefore, such polyisocyanurates exhibit the highest market potential for the PIR recycling process of the present invention.

[0055] In the process of the present invention, the polyisocyanurate is contacted with water in the presence of an organic amine base.

[0056] Preferred organic amine bases are selected from the group consisting of aliphatic amines, aromatic amines, heteroaromatic amines and mixtures thereof, more preferably the organic amine base is an aliphatic amine containing one or more tertiary nitrogen atoms and / or having a boiling point lower than that of at least one, preferably two or more, more preferably all of the organic amines obtained as products of polyisocyanurate hydrolysis.

[0057] A wide variety of organic amine bases that can be easily separated from the reaction products of PIR hydrolysis, preferably by distillation or extraction, can be used in the process of the present invention to effectively depolymerize PIR.

[0058] Preferably, the organic amine base is used as a non-ionic organic base in the method of the present invention. "Non-ionic" means that the base is not in the form of a salt, i.e., does not contain anions or cations, before being added to the reaction mixture. "Organic amine base" is a compound that contains nitrogen in addition to carbon and hydrogen and reacts with acids to form salt-like compounds. Preferably, the "organic amine base" contains one or more C-H bonds.

[0059] The organic amine base used in the present invention contains one or more nitrogen atoms. The nitrogen atoms can be primary, i.e., NHR, secondary, i.e., NHR, and / or tertiary, i.e., NR, where R is an alkyl group. Preferably, the organic base contains one or more tertiary nitrogen atoms. Without being bound by any theory, the applicants believe that the tertiary nitrogen atoms do not form urea when reacting with polyurethane, and therefore catalyze the direct hydrolysis of polyisocyanurate compared to primary or secondary amino groups.

[0060] In contrast to the use of inorganic bases, the use of such organic amine bases in the present invention significantly reduces the amount of salt in the reaction solution that needs to be separated and disposed of, increasing the sustainability of the method. The inventors have surprisingly found that the organic amine bases used in the present invention can be used without adding a phase transfer catalyst, for example, without adding a quaternary ammonium salt as a phase transfer catalyst. This allows for a further reduction in the salt load of the reaction mixture, providing additional ecological and economic benefits.

[0061] The organic amine base used in the present invention is preferably an aliphatic amine having a boiling point lower than that of at least one, preferably two or more, and more preferably all, of the organic polyamines produced as products of PIR hydrolysis.

[0062] The use of an aliphatic organic amine base allows for shorter reaction times and lower temperatures without a decrease in polyol yield.

[0063] Preferred organic amine base(s) are: - a base according to formula (1) (((R 3 )2N-R 2 )-(OR 1 ) x ) y -N(R 4 ) z (1) During the ceremony, R in the molecule 1 The groups can be the same or different and R 2 The groups can be the same or different and R 3 The groups can be the same or different, and the R 4 The groups can be the same or different, R 1 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, most preferably ethylene, propylene or isopropylene. R 2 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene or hydroxyalkylene groups having 1 to 20, preferably 1 to 18, more preferably 2 to 6, and even more preferably 2 to 4 carbon atoms; R 2 is hydroxyalkylene, R 2 contain 1 to 5, preferably 1, 2 or 3, more preferably 1 or 2, most preferably 1 hydroxy group, and are most preferably selected independently from the group consisting of ethylene, propylene, butylene, hexamethylene, 2-hydroxypropylene or isopropylene. R 3 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO)u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl, R 4 are the same or different and are selected from hydrogen, a straight-chain or branched, cyclic or alicyclic alkyl group having 1 to 20, preferably 1 to 18, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, and more preferably 1, 2 or 3 carbon atoms, and a cycloalkyl residue having 6 to 18, preferably 6 to 12, more preferably 6 to 10, and even more preferably 6 or 7 carbon atoms, (CHCHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably selected independently from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, cyclohexyl, isopropyl, tertbutyl, cyclohexyl, methylcyclohexyl, 2-cyclohexyl-ethyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 6-hydroxyhexyl and 2-hydroxyisopropyl, u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 x=0 or 1 y=0~3 z=0 to 3, provided that when z=3, one, preferably two, and more preferably all three R 4 is not hydrogen, y+z=3 - a base according to formula (2) (((R 6 )2N-R5 ) a (H) b N) d -CZ-(N(R 7 )2) c (2) During the ceremony, R in the molecule 5 The groups may be the same or different and may be separated by a residue R 6 The groups may be the same or different and the residues R 7 The groups can be the same or different, R 5 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, in which one or more CH groups may be replaced by O to form an ether bond, and preferably R 5 is ethylene, propylene or isopropylene R 6 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably independently selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; R 7 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) vH and (CHCH(CH)CHO) w H, most preferably independently selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl; Z=O or NH, u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 a=0, 1 or 2 b=0, 1 or 2 a+b=2 c=0, 1 or 2 d=0, 1 or 2 c+d=2 - a cyclic or bicyclic, aromatic or non-aromatic nitrogen-containing organic base containing 4 to 20 carbon atoms, preferably 5 to 14, more preferably 5 to 12 and most preferably 6 to 10 carbon atoms and 1 to 4 nitrogen atoms, preferably 1 to 3, more preferably 1, 2 or 3 nitrogen atoms, optionally the cyclic or bicyclic, aromatic or non-aromatic nitrogen-containing organic base containing one or more O atoms and / or a linear or branched alkyl or alkenyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a linear or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl or one or more N- and / or O-containing functional groups, and / or two or more cyclic or bicyclic, non-aromatic nitrogen-containing organic rings are bonded to each other via alkylene or ether alkylene linkages having 1 to 12, preferably 1 to 6, carbon atoms, - and mixtures thereof is selected from the group consisting of:

[0064] The most preferred organic amine base(s) are: - trialkylamines according to formula (3), as preferred embodiments of formula (1) NR 4 R 4’ R 4” (3) R 4 , R 4’ , R 4” are the same or different and are selected from hydrogen, a straight-chain or branched, cyclic or alicyclic alkyl group having 1 to 20, preferably 1 to 18, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, and more preferably 1, 2 or 3 carbon atoms, and a cycloalkyl residue having 6 to 18, preferably 6 to 12, more preferably 6 to 10, and even more preferably 6 or 7 carbon atoms, (CHCHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, cyclohexyl, isopropyl, tertbutyl, cyclohexyl, methylcyclohexyl, 2-cyclohexyl-ethyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 6-hydroxyhexyl and 2-hydroxyisopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 However, R 4 , R 4’ and R 4” One, preferably two, more preferably all three of are not hydrogen. - polyamines according to formula (4), as another preferred embodiment of formula (1) ((R 3)2N-R 2 )3N(4), During the ceremony, R 2 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene or hydroxyalkylene groups having 1 to 20, preferably 1 to 18, more preferably 2 to 6, and even more preferably 2 to 4 carbon atoms; R 2 When R is hydroxyalkyl, 2 contain 1 to 5, preferably 1, 2 or 3, more preferably 1 or 2, most preferably 1 hydroxy group, and are most preferably selected independently from the group consisting of ethylene, propylene or isopropylene. R 3 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl, u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 - polyamines according to formula (5) as a further preferred embodiment of formula (1) (((R 3 )2N-R 2 )-(OR 1 ) x ) y -N(R 4 ) z (5) In the formula, x=0 or 1, y=1 or 2 and z=1 or 2 and y+z=3 R1 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, most preferably ethylene, propylene or isopropylene. R 2 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene or hydroxyalkylene groups having 1 to 20, preferably 1 to 18, more preferably 2 to 6, more preferably 2 to 4 carbon atoms; R 2 When R is hydroxyalkyl, 2 contain 1 to 5, preferably 1, 2 or 3, more preferably 1 or 2, most preferably 1 hydroxy group, and are most preferably selected independently from the group consisting of ethylene, propylene, butylene, hexamethylene, 2-hydroxypropylene or isopropylene; R 3 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably selected independently from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl; R 4 are the same or different and are hydrogen, a straight-chain or branched, cyclic or alicyclic alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) wH, most preferably selected independently from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, cyclohexyl, isopropyl, tertbutyl, cyclohexyl, methylcyclohexyl, 2-cyclohexyl-ethyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 6-hydroxyhexyl and 2-hydroxyisopropyl. u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 - polyaminoalkylureas according to formula (6), as a preferred embodiment of formula (2) (((R 6 )2N-R 5 ) a (H) b N) d -CO-(N(R 7 )2) c (6) During the ceremony, R 5 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, in which one or more CH groups may be replaced by O to form an ether bond, and preferably R 5 is ethylene, propylene or isopropylene R 6 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) wH, most preferably independently selected from the group consisting of methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; R 7 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably independently selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 a=0, 1 or 2 b=0, 1 or 2 a+b=2 c=0, 1 or 2 d=0, 1 or 2 c+d=2, In a further preferred embodiment of formula (2), the organic base is a guanidino group according to formula (7) (((R6)2N-R5) a (H) b N) d -C(NH)-(N(R7)2) c (7) During the ceremony, R 5 are the same or different and are independently selected from the group consisting of straight or branched chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, in which one or more CH groups may be replaced by O to form an ether bond, and preferably R 5is ethylene, propylene or isopropylene R 6 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably independently selected from the group consisting of methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; R 7 are the same or different and are hydrogen, a straight-chain or branched-chain alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched-chain hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH2CHO) u H, (CH2CH2CH2O) v H and (CHCH(CH)CHO) w H, most preferably independently selected from the group consisting of methyl, ethyl, propyl, isopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 a=0, 1 or 2 b=0, 1 or 2 a+b=2 c=0, 1 or 2, preferably 0 or 1, more preferably 0 d=0, 1 or 2, preferably 1 or 2, more preferably 2 c+d=2, - and mixtures thereof is selected from the group consisting of:

[0065] The most preferred organic amine bases are triethylamine, tripropylamine, N,N-dimethyl-N-propylamine, N,N-dimethyl-N-butylamine, N,N-dimethyl-N-pentylamine, N,N-dimethyl-N-hexylamine, N,N-dimethyl-N-cyclohexylamine, N,N-dimethyl-N-heptylamine, N,N-dimethyl-N-octylamine, N,N-diethyl-N-propylamine, N,N-diethyl-N-butylamine, N,N-diethyl-N-pentylamine, N,N-diethyl-N-hexylamine, N,N-diethyl-N-cyclohexylamine, N,N-diethyl-N-heptylamine, N,N-diethyl-N-octylamine, tetramethylethylenediamine (TMEDA), tetramethyl-1,3-propylenediamine (TMPDA), tetramethyl- 1,4-butylenediamine (TMBDA), tetramethyl-1,6-hexa-methylenediamine (TMHMDA), pentamethyldiethylenetriamine (PMDETA), N,N,N'N'-tetramethyl-bis(aminoethyl)ether, N,N'-dimethyl-piperazine, 1,4-diazabicyclo(2,2,2)octane (TEDA), trimethyl-triaza-cyclononane (TACN); dimethylethanolamine, dimethylaminoethoxyethanol, N,N-dimethyl-aminoethyl-N'-methyl-ethanolamine, tetramethylguanidine, N,N-bis(3-dimethylamino-propyl)-N-(2-hydroxypropyl)amine, N,N-dimethyl-N',N'-bis(2-hydroxypropyl)-1,3-propylenediamine, dimethyl-aminopropylamine (DMAPA);N-Methyl-N-2-hydroxypropyl-piperazine, Bis(dimethylaminopropyl)-amine, Dimethylaminopropylurea, N,N'-Bis(3-dimethylaminopropyl)urea, 1,3-Bis(dimethylamino)-2-propanol, 6-Dimethylamino-1-hexanol, N,N'-Bis(2-hydroxypropyl)piperazine, N-(2-hydroxypropyl)-morpholine, 1,2-Dimethylimidazole, 1-Ethylimidazole, N N-methyl-pyrrolidine, N-ethyl-pyrrolidine, N-(2-hydroxyethyl)-pyrrolidine, N-(2-hydroxypropyl)-pyrrolidine, N-propyl-pyrrolidine, N-allyl-pyrrolidine, N-methyl-piperidine, N-ethyl-piperidine, N-(2-hydroxyethyl)-piperidine, N-(2-hydroxypropyl)-piperidine, N-propyl-piperidine, N-allyl-piperidine and mixtures thereof;

[0066] Instead of aliphatic amines, aromatic amines can be used in the present invention. Preferably, an aromatic amine corresponding to the isocyanate used to prepare the PIR is used. This method is advantageous because the amine used as the hydrolysis catalyst is the same as the amine recovered from the PIR and does not need to be separated from each other. The amine formed during hydrolysis can function as a cocatalyst with the amine base added to the reaction mixture. This allows for a reduction in the amount of amine base that must be added to the reaction mixture. Furthermore, the amine recovered from the method of the present invention can be reused as a hydrolysis catalyst in the method of the present invention.

[0067] More preferably, the following aromatic amine catalysts can be used, selected from the group consisting of anilines, preferably dimethylaniline and 4,4'-methylenedianiline (MDA), pyridines, and imidazolines, such as 1,3-dimethyl-2-imidazolidinone (DMI). These aromatic amine catalysts are less susceptible to oxidation than aliphatic amines. There is less likelihood of by-products, such as DMF or formaldehyde, being formed due to the oxidation process.

[0068] The use of the aforementioned amine bases makes it possible to carry out the process of the present invention in standard equipment, preferably in steel reactors, without special corrosion protection, thus contributing significantly to reducing the investment costs of the plant. It is also possible to use very cheap bases, which contributes to reducing operating costs.

[0069] The amount of organic amine base in the reaction mixture must be sufficient to catalyze the desired hydrolysis of the polyisocyanurate at a practically acceptable rate. Preferably, the amine is used in a stoichiometric amount relative to the polyisocyanurate, or an excess of amine is used. More preferably, the weight ratio of the total organic amine base to the polyisocyanurate is in the range of 1:100 to 50:1, preferably 1:50 to 25:1, more preferably 1:10 to 20:1, even more preferably 1:5 to 10:1, and most preferably 1:2 to 3:1. Preferably, the base is used in the form of a base solution containing the base and water, even more preferably as a saturated base solution.

[0070] In the method of the present invention, PIR can be reacted with an amine and water, or the polyisocyanurate can be contacted with water in the presence of an organic amine base and a phase transfer catalyst, preferably selected from the group consisting of quaternary ammonium salts containing ammonium cations and having 6 to 30 carbon atoms and organic sulfonates containing at least 7 carbon atoms. The use of a phase transfer catalyst has been shown to increase the yield of the reaction product and allow the reaction to be carried out at lower temperatures and in shorter reaction times.

[0071] Preferred quaternary ammonium salts for use as phase transfer catalysts preferably have the general structure R1R2R3R4NX, where R1, R2, R3 and R4 are the same or different and are hydrocarbyl groups selected from alkyl, aryl and arylalkyl, and X is selected from the group consisting of halides, preferably chloride and / or bromide, hydrogen sulfate, alkyl sulfates, preferably methyl sulfate and ethyl sulfate, carbonate, hydrogen carbonate, carboxylate, preferably acetate, or hydroxide.

[0072] More preferably, R1, R2, R3 and R4 and X are defined as follows: - R1 and R2 are the same or different and are alkyl groups having 1 to 12, preferably 1 to 10, more preferably 1 to 7, even more preferably 1 to 6, particularly preferably 1 to 5, and most preferably 1 to 4 carbon atoms, which alkyl groups may be linear, branched, cyclic, saturated or unsaturated, and are most preferably linear, saturated alkyl groups; R3 is selected from the group consisting of alkyl groups having 1 to 12, preferably 1 to 10, more preferably 1 to 7, even more preferably 1 to 6, particularly preferably 1 to 5, and most preferably 1 to 4 carbon atoms, aryl groups having 6 to 14, preferably 6 to 12, and most preferably 6 to 10 carbon atoms, and aralkyl groups having 7 to 14, preferably 7 to 12, and most preferably 7 to 10 carbon atoms, wherein the alkyl groups may be linear, branched, cyclic, saturated or unsaturated, and are most preferably linear; R4 is selected from the group consisting of alkyl groups having 3 to 12, preferably 3 to 10, more preferably 3 to 7, and most preferably 4 to 6 carbon atoms, aryl groups having 6 to 14, preferably 6 to 12, and most preferably 6 to 10 carbon atoms, and aralkyl groups having 7 to 14, preferably 7 to 12, and most preferably 7 to 10 carbon atoms, wherein the alkyl groups may be linear, branched, cyclic, saturated or unsaturated, and are most preferably linear and saturated; X is selected from the group consisting of halides, preferably chloride and / or bromide, hydrogen sulfate, alkyl sulfate, preferably methyl sulfate and ethyl sulfate, carbonate, hydrogen carbonate, acetate or hydroxide.

[0073] Even more preferable R1 to R4 are the total number of carbon atoms in the quaternary ammonium cation is 6 to 14, preferably 7 to 14, and more preferably 8 to 13; or The total number of carbon atoms in the quaternary ammonium cation is 15 to 30, preferably 15 to 28, more preferably 15 to 24, even more preferably 16 to 22, and most preferably 16 to 20. are selected from the definitions given above.

[0074] Particularly preferably, R1 to R4 and X are selected so that the total number of carbon atoms in the quaternary ammonium salt is 6 to 14, preferably 7 to 14, more preferably 8 to 13; or R1 to R4 and X are selected so that the total number of carbon atoms in the quaternary ammonium salt is 15 to 30, preferably 15 to 28, more preferably 15 to 24, even more preferably 16 to 22, and most preferably 16 to 20.

[0075] Although the addition of even trace amounts of phase transfer catalyst will accelerate the rate of hydrolysis, it is preferred to use at least 0.5 weight percent of catalyst, based on the weight of the polyisocyanurate, more preferably 0.5 to 15 weight percent, even more preferably 1 to 10 weight percent, especially more preferably 1 to 8 weight percent, very preferably 1 to 7 weight percent, and most preferably 2 to 6 weight percent.

[0076] In another preferred embodiment, one or more inorganic bases containing alkali metal cations, preferably one or more inorganic bases containing alkali metal cations, are added to the reaction mixture during or after hydrolysis to obtain alkali metal or alkaline earth metal or mixed alkali metal and alkaline earth metal salts of one or more carboxylic acids containing two or more carboxylic acid groups per molecule and corresponding to the carboxylic acid(s) used to prepare the polyester polyol(s) formed during hydrolysis and used to prepare the polyisocyanurate. It has been shown that such alkali metal or alkaline earth metal or mixed alkali metal and alkaline earth metal salts, preferably alkali metal salts, of one or more carboxylic acids can be more easily separated from other components of the reaction solution than the ammonium salts that would otherwise form during the hydrolysis reaction. Without being bound by any theory, the inventors believe that the higher solubility of such alkali metal or alkaline earth metal or mixed alkali metal and alkaline earth metal salts in water contributes to this improvement.

[0077] Preferably, an alkali metal base is used selected from the group consisting of alkali metal phosphates, alkali metal hydrogen phosphates, alkali metal carbonates, alkali metal silicates, alkali metal hydrogen carbonates, alkali metal acetates, alkali metal sulfites, ammonium hydroxide, and mixtures thereof. More preferably, the alkali metal is selected from the group consisting of Na, K, and Li, and mixtures thereof, most preferably Na and K, and mixtures thereof.

[0078] Preferred weight ratios of the total inorganic base to the polyisocyanurate range from 5:1 to 1:120, preferably 4:1 to 1:80, more preferably 3:1 to 1:40, even more preferably 2:1 to 1:20, and most preferably 1:1 to 1:10. More preferably, the amount of inorganic base is selected to quantitatively convert one or more carboxylic acids to alkali metal or alkaline earth metal or mixed alkali metal and alkaline earth metal salts, preferably alkali metal salts.

[0079] The inorganic base can be added to the reaction mixture as a solid material or in an aqueous solution. Preferably, the inorganic base is used in the form of a saturated aqueous base solution.

[0080] Water functions as a reactant in the hydrolysis reaction of the present invention, and therefore need not be present in stoichiometric excess relative to the isocyanurate functional groups in the polymer being hydrolyzed; it is generally desirable to utilize a substantial amount of water, as it can conveniently serve as a reaction medium and solvent or carrier for the strong base and activator. For these reasons, water is preferably present in condensed (liquid) form. Typically, the weight ratio of PIR to water is 3:1 to 1:15.

[0081] Preferably, the polyisocyanurate is reacted with water and an organic amine base, or with water, an organic amine and a phase transfer catalyst. At a temperature of 80°C to 220°C, preferably 100°C to 200°C, more preferably 120°C to 190°C, and most preferably 140°C to 180°C and / or 1 minute to 48 hours, preferably 1 minute to 40 hours, more preferably 5 minutes to 35 hours, even more preferably 10 minutes to 30 hours, particularly preferably 20 minutes to 24 hours, very preferably 30 minutes to 18 hours, and most preferably 30 minutes to 16 hours and / or At atmospheric pressure or a pressure of 1 to 30 bar, 2 to 20 bar, more preferably 3 to 15 bar These reaction conditions provide economic benefits in terms of energy consumption and space-time yield. If the temperature is too low, the conversion may be incomplete or the reaction time may be too long. If the reaction temperature is too high or the reaction time is extended outside the aforementioned range, increased formation of by-products is observed, and energy consumption increases to unacceptable levels. The formation of by-products may result in undesirable coloration of the recovered product, which creates the need for additional purification steps. It has been found that conducting the reaction under elevated pressure shortens the reaction time and allows operation at lower temperatures.

[0082] To facilitate handling of the PIR, preferably a PIR foam, it is desirable to chop, powder, pulverize, or otherwise comminute the PIR so that it is in the form of relatively small particles or granules. If the PIR is a foam, it can be partially or fully compressed before contacting with water and the organic amine base. If the PIR is in solid form, an initial powdering step is highly advantageous for maximizing the surface area available for reaction (thereby shortening the reaction time required to achieve the desired level of hydrolysis).

[0083] The process of the present invention results in efficient hydrolytic cleavage of the isocyanurate linkages present in the PIR being treated. Under these reaction conditions, the polyester polyol obtained after ring cleavage of the isocyanurate linkages is further hydrolyzed to give the corresponding carboxylic acid and polyol.

[0084] Therefore, in the method of the present invention, one or more carboxylic acids containing two or more carboxylic acid groups per molecule and corresponding to the carboxylic acid(s) used to prepare the polyester polyol(s) used to prepare the polyisocyanurate, and one or more polyols corresponding to the polyol(s) used to prepare the polyester polyol(s) used to prepare the polyisocyanurate, and one or more organic amines and / or polyamines corresponding to the organic isocyanates or polyisocyanates used to prepare the polyisocyanurates is obtained.

[0085] Preferably, the one or more carboxylic acids obtained after hydrolysis are selected from the group consisting of phthalic acid, preferably (ortho)phthalic acid, isophthalic acid, terephthalic acid and the isomeric naphthalenedicarboxylic acids, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, fumaric acid and mixtures thereof.

[0086] Also preferred polyol(s) obtained after hydrolysis are diols based on glycols and / or glycol ethers having a molecular weight of less than 180 g / mol, preferably less than 140 g / mol, particularly preferred are monoethylene glycol and / or diethylene glycol.

[0087] More preferably, the one or more organic amines and / or polyamines obtained after hydrolysis are dodecane 1,12-diamine, 2-ethyltetramethylene 1,4-diamine, 2-methylpentamethylene 1,5-diamine, tetramethylene 1,4-diamine, pentamethylene diamine (PDA) and preferably hexamethylene 1,6-diamine (HMDA), cyclohexane 1,3- and 1,4-diamine and any mixtures of these isomers, 4,4'-methylenedicyclohexyl diisocyanate (H12MDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl Cycloaliphatic diamines such as cyclohexane (isophorone diamine or IPDA for short), hexahydrotolylene 2,4- and 2,6-diamine and the corresponding isomeric mixtures, and preferably aromatic diamines and polyamines, such as toluene 2,4- and 2,6-diamine (TDA) and the corresponding isomeric mixtures, naphthalenediamine, diethyltoluenediamine, mixtures of diphenylmethane 4,4',2,4'- and 2,2'-diamine (MDA) and polyphenylpolymethylenepolyamines and their more highly condensed analogues with an average functionality of 2 to 4.

[0088] The hydrolysis reaction can be carried out as a batch, continuous, or semi-continuous process in any suitable vessel or other apparatus (e.g., a stirred tank reactor or a screw extruder). Agitation or stirring of the reaction components is generally preferred to ensure intimate contact, a rapid rate of hydrolysis, and adequate temperature control.

[0089] The method of the present invention is advantageous over prior art processes because the hydrolysis reaction can be carried out as a one-step process. Preferably, the PIR is not subjected to reaction with pure amine or pure water before being subjected to hydrolysis with water and an organic amine base, or with water, an organic amine base, and a phase transfer catalyst.

[0090] It is further preferred that the method of the present invention does not include the step of isolating the reaction product of the organic amine base and PIR followed by subsequent hydrolysis of the isolated reaction product.

[0091] After completion of the hydrolysis step, the reaction products are preferably separated from each other and, optionally, subjected to a purification step. Preferred separation and purification methods are selected from the group consisting of filtration, membrane separation, phase separation, chromatographic methods, distillation, extraction, and combinations of the above methods. Preferably, the amine components, i.e., the amine bases and / or amines obtained as reaction products of the hydrolysis, are separated from the other components by distillation or extraction, more preferably by distillation.

[0092] The recovered products of the process of the present invention, particularly one or more carboxylic acids and / or polyols and / or organic amines and / or polyamines, can be reused for the production of new chemicals, preferably polyurethanes, preferably polyurethane foams, or polyisocyanurates, preferably polyisocyanurate foams. The inventors have found that the recovered products of the process of the present invention can be used to produce high-quality PIR polyurethane foams, even without the addition of virgin polyols. This is a significant achievement.

[0093] The recovered amines can be converted to organic polyisocyanates by conventional processes and similarly used as components of polyurethanes or PIRs.

[0094] Without further elaboration, it is believed that one skilled in the art can, using the preceding description, utilize the present invention to its fullest extent. The following examples, therefore, should be construed as merely illustrative, and not limitative of the claims or the remainder of the disclosure in any way whatsoever.

[0095] Example Preparation of recycled PIR foam The formulations listed in Table 1 were used to prepare the PIR foams used in the hydrolysis tests described in Example 1 below. The PIR foams were prepared by manual mixing. For this purpose, the polyol, flame retardant, catalyst, water, foam stabilizer, and blowing agent were weighed into a beaker and mixed with a disk stirrer (6 cm diameter) at 1000 rpm for 30 seconds. The amount of blowing agent evaporated during the mixing operation was determined by reweighing and replenished. Subsequently, the isocyanate (MDI) was added, and the reaction mixture was stirred with the described stirrer at 3000 rpm for 5 seconds. In the case of pour-in-place foaming, foaming was carried out in the beaker itself; otherwise, the mixture was transferred to a paper-lined box with a base area of ​​27 × 14 cm.

[0096] [Table 1] * Stepanpol® PS 3152 from Stepan, OH value 315 mg KOH / g ** POLYCAT® 5 (pentamethyldiethylenetriamine) from Evonik Operations GmbH *** KOSMOS® 70LO from Evonik Operations GmbH **** TEGOSTAB® B8411 from Evonik Operations GmbH ***** Fyrol® PCF from ICL Industrial Products ****** Polymeric MDI, 200mPa*s, 31.5% NCO, functionality 2.7.

[0097] Example 1 The PIR foam prepared as described above was milled. 120 g of the milled PIR foam was transferred to a 5 L pressure reactor along with 862 g of DABCO® BL19 (bis-(2-dimethylaminoethyl) ether) and 218 g of water. The mixture was heated to 170°C and stirred for 5 hours. A pressure of approximately 11 bar was built up. A cloudy, brownish, completely liquid product was obtained, which showed phase separation after standing for 12 hours. C-NMR showed only traces of urethane, urea, and isocyanurate groups, indicating >98% conversion.

[0098] Example 2 The PIR foam prepared as described above was milled. 100 g of the milled PIR foam was transferred into a 2 L pressure reactor along with 718 g of 1,2-dimethylimidazole and 182 g of water. The mixture was heated to 170 °C and stirred for 5 h. A pressure of approximately 8-10 bar was created. A cloudy, brownish, completely liquid product was obtained. C-NMR showed only traces of urethane, urea, and isocyanurate groups, indicating >98% conversion.

[0099] Example 3 The PIR foam prepared as described above was milled. 100 g of the milled PIR foam was transferred into a 2 L pressure reactor along with 718 g of POLYCAT® 206 (a tertiary amine catalyst) and 182 g of water. The mixture was heated to 170°C and stirred for 5 hours. A pressure of approximately 15-17 bar was created. A cloudy, yellowish, completely liquid product was obtained, which showed phase separation after standing. C-NMR showed only traces of urethane, urea, and isocyanurate groups, indicating >98% conversion.

Claims

1. 1. A method for hydrolyzing a polyisocyanurate, comprising: the polyisocyanurate is prepared by reacting one or more polyols selected from the group consisting of polyester polyols, mixtures of polyester polyols, and mixtures of polyester polyols and polyether polyols with an excess of one or more isocyanates selected from the group consisting of organic isocyanates, mixtures of organic isocyanates, organic polyisocyanates, mixtures of organic polyisocyanates, and mixtures of organic isocyanates and organic polyisocyanates; and contacting the polyisocyanurate with water in the presence of an organic amine base, one or more carboxylic acids containing two or more carboxylic acid groups per molecule and corresponding to the carboxylic acids used to prepare the polyester polyols used to prepare the polyisocyanurates; one or more polyols corresponding to the polyols used to prepare the polyester polyols used to prepare the polyisocyanurates; one or more organic amines and / or polyamines corresponding to the organic isocyanates or polyisocyanates used to prepare the polyisocyanurates; to obtain and The reaction mixture containing the polyisocyanurate, water, and the organic amine base is a stirred homogeneous or heterogeneous mixture, preferably a solution, emulsion, dispersion, or a combination thereof, during hydrolysis. A method characterized by:

2. contacting the polyisocyanurate with water in the presence of an organic amine base and a phase transfer catalyst, preferably selected from the group consisting of quaternary ammonium salts containing ammonium cations containing 6 to 30 carbon atoms and organic sulfonates containing at least 7 carbon atoms; The method of claim 1.

3. the organic amine base is selected from the group consisting of aliphatic amines, aromatic amines, heteroaromatic amines and mixtures thereof, preferably the organic amine base is an aliphatic amine containing one or more tertiary nitrogen atoms and / or having a boiling point lower than that of at least one, preferably two or more, more preferably all of the organic amines obtained as a product of polyisocyanurate hydrolysis, 3. The method according to claim 1 or 2.

4. The organic amine base is a base according to formula (1) (((R ３ ) ２ N-R ２ )-(O-R １ ) ｘ ) ｙ -N(R ４ ) ｚ (1) During the ceremony, The R in the molecule １ The groups may be the same or different, and the R ２ The groups may be the same or different, and the R ３ The groups may be the same or different, and the R ４ The groups can be the same or different, R １ are the same or different and are independently selected from the group consisting of straight or branched chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, most preferably ethylene, propylene or isopropylene. R ２ are the same or different and are independently selected from the group consisting of straight or branched chain alkylene or hydroxyalkylene groups having 1 to 20, preferably 1 to 18, more preferably 2 to 6, and even more preferably 2 to 4 carbon atoms; R ２ is hydroxyalkylene, R ２ contain 1 to 5, preferably 1, 2 or 3, more preferably 1 or 2, most preferably 1 hydroxy group, and are most preferably selected independently from the group consisting of ethylene, propylene, butylene, hexamethylene, 2-hydroxypropylene or isopropylene. R ３ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; R ４ are the same or different and are selected from the group consisting of hydrogen, straight-chain or branched, cyclic or alicyclic alkyl groups having 1 to 20, preferably 1 to 18, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1, 2 or 3 carbon atoms, straight-chain or branched hydroxyalkyl groups having 1 to 6, preferably 1 to 4, and more preferably 1, 2 or 3 carbon atoms, and cycloalkyl residues having 6 to 18, preferably 6 to 12, more preferably 6 to 10, and even more preferably 6 or 7 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably selected independently from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, cyclohexyl, isopropyl, tertbutyl, cyclohexyl, methylcyclohexyl, 2-cyclohexyl-ethyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 6-hydroxyhexyl and 2-hydroxyisopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 x=0 or 1 y=0 to 3 z=0 to 3, provided that when z=3, one, preferably two, and more preferably all three R ４ is not hydrogen, y + z = 3 a base according to formula (2) (((R ６ ) ２ N-R ５ ) ａ (H) ｂ N) ｄ -CZ-(N(R ７ ) ２ ) ｃ (2) During the ceremony, The R in the molecule ５ The groups may be the same or different and the residues R ６ The groups may be the same or different, and the residues R ７ The groups can be the same or different, R ５ are the same or different and are independently selected from the group consisting of straight-chain or branched-chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, and ２ The group may be substituted by O to form an ether bond, preferably R ５ is ethylene, propylene or isopropylene R ６ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably independently selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; R ７ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably independently selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl; Z=O or NH, u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 a=0, 1 or 2 b=0, 1 or 2 a + b = 2 c=0, 1 or 2 d=0, 1 or 2 c + d = 2 - a cyclic or bicyclic, aromatic or non-aromatic nitrogen-containing organic base containing 4 to 20 carbon atoms, preferably 5 to 14, more preferably 5 to 12 and most preferably 6 to 10 carbon atoms and 1 to 4 nitrogen atoms, preferably 1 to 3, more preferably 1, 2 or 3 nitrogen atoms, optionally said cyclic or bicyclic, aromatic or non-aromatic nitrogen-containing organic base containing one or more O atoms and / or a linear or branched alkyl or alkenyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a linear or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl or one or more N- and / or O-containing functional groups, and / or two or more cyclic or bicyclic, non-aromatic nitrogen-containing organic rings are bonded to each other via alkylene or ether alkylene linkages having 1 to 12, preferably 1 to 6, carbon atoms; - and mixtures thereof The method according to any one of claims 1 to 3, characterized in that the compound is selected from the group consisting of:

5. The organic amine base is - a trialkylamine according to formula (3) NR ４ R ４’ R ４” (3) R ４ , R ４’ , R ４” are the same or different and are selected from the group consisting of hydrogen, straight-chain or branched, cyclic or alicyclic alkyl groups having 1 to 20, preferably 1 to 18, more preferably 1 to 6, even more preferably 1 to 4, and most preferably 1, 2 or 3 carbon atoms, straight-chain or branched hydroxyalkyl groups having 1 to 6, preferably 1 to 4, and more preferably 1, 2 or 3 carbon atoms, and cycloalkyl residues having 6 to 18, preferably 6 to 12, more preferably 6 to 10, and even more preferably 6 or 7 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably independently selected from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, cyclohexyl, isopropyl, tertbutyl, cyclohexyl, methylcyclohexyl, 2-cyclohexyl-ethyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 6-hydroxyhexyl and 2-hydroxyisopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 However, R ４ , R ４’ and R ４” is not hydrogen, - a polyamine according to formula (4) ((R ３ ) ２ N-R ２ ) ３ N(4)、 During the ceremony, R ２ are the same or different and are independently selected from the group consisting of straight or branched chain alkylene or hydroxyalkylene groups having 1 to 20, preferably 1 to 18, more preferably 2 to 6, and even more preferably 2 to 4 carbon atoms; R ２ is hydroxyalkyl, R ２ contain 1 to 5, preferably 1, 2 or 3, more preferably 1 or 2, most preferably 1 hydroxy group, and are most preferably selected independently from the group consisting of ethylene, propylene, butylene, hexamethylene, 2-hydroxypropylene or isopropylene. R ３ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably hydrogen, methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 - a polyamine according to formula (5) (((R ３ ) ２ N-R ２ )-(O-R １ ) ｘ ) ｙ -N(R ４ ) ｚ (5) wherein x=0 or 1, y=1 or 2 and z=1 or 2 and y+z=3 R １ are the same or different and are independently selected from the group consisting of straight or branched chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, most preferably ethylene, propylene or isopropylene. R ２ are the same or different and are independently selected from the group consisting of straight or branched chain alkylene or hydroxyalkylene groups having 1 to 20, preferably 1 to 18, more preferably 2 to 6, more preferably 2 to 4 carbon atoms; R ２ is hydroxyalkyl, R ２ contain 1 to 5, preferably 1, 2 or 3, more preferably 1 or 2, most preferably 1 hydroxy group, and are most preferably selected independently from the group consisting of ethylene, propylene, butylene, hexamethylene, 2-hydroxypropylene or isopropylene; R ３ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably hydrogen, methyl, ethyl, propyl, isopropyl; R ４ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched, cyclic or alicyclic alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably selected independently from the group consisting of methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, octyl, cyclohexyl, isopropyl, tertbutyl, cyclohexyl, methylcyclohexyl, 2-cyclohexyl-ethyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 6-hydroxyhexyl and 2-hydroxyisopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 - a polyaminoalkylurea according to formula (6) (((R ６ ) ２ N-R ５ ) ａ (H) ｂ N) ｄ -A--(N(R ７ ) ２ ) ｃ (6) During the ceremony, R ５ are the same or different and are independently selected from the group consisting of straight-chain or branched-chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, and ２ The group may be substituted by O to form an ether bond, preferably R ５ is ethylene, propylene or isopropylene R ６ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably independently selected from the group consisting of methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; R ７ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably independently selected from the group consisting of hydrogen, methyl, ethyl, propyl, isopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 a=0, 1 or 2 b=0, 1 or 2 a + b = 2 c=0, 1 or 2 d=0, 1 or 2 c+d=2, an organic base containing a guanidino group according to formula (7) (((R ６ ) ２ N-R ５ ) ａ (H) ｂ N) ｄ -C(NH)-(N(R ７ ) ２ ) ｃ (7) During the ceremony, R ５ are the same or different and are independently selected from the group consisting of straight-chain or branched-chain alkylene groups having 1 to 10, preferably 2 to 6, more preferably 2 to 4 carbon atoms, and ２ The group may be substituted by O to form an ether bond, preferably R ５ is ethylene, propylene or isopropylene R ６ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably independently selected from the group consisting of methyl, ethyl, propyl, isopropyl, hydroxymethyl, 2-hydroxyethyl, 3-hydroxypropyl, 2-hydroxypropyl, 2-hydroxyisopropyl; R ７ are the same or different and are selected from the group consisting of hydrogen, a straight-chain or branched alkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, a straight-chain or branched hydroxyalkyl group having 1 to 6, preferably 1 to 4, more preferably 1, 2 or 3 carbon atoms, (CH ２ CH ２ O) ｕ H, (CH ２ CH ２ CH ２ O) ｖ H and (CH ２ CH (CH ３ ) CH ２ O) ｗ H, most preferably independently selected from the group consisting of methyl, ethyl, propyl, isopropyl; u=1 to 14, preferably 1 to 6 v=1 to 14, preferably 1 to 6 w=1 to 14, preferably 1 to 6 a=0, 1 or 2 b=0, 1 or 2 a + b = 2 c=0, 1 or 2, preferably 0 or 1, more preferably 0 d=0, 1 or 2, preferably 1 or 2, more preferably 2 c+d=2, - and mixtures thereof 5. The method of claim 4, wherein the compound is selected from the group consisting of:

6. The phase transfer catalyst has the general structure R １ R ２ R ３ R ４ NX, wherein R １ , R ２ , R ３ and R ４ are the same or different and are hydrocarbyl groups selected from alkyl, aryl and arylalkyl, and X is selected from the group consisting of halides, preferably chloride and / or bromide, hydrogen sulfate, alkyl sulfates, preferably methyl sulfate and ethyl sulfate, carbonate, hydrogen carbonate, carboxylates, preferably acetate, or hydroxide, The method according to any one of claims 2 to 5.

7. -R １ and R ２ are the same or different and are alkyl groups having 1 to 12, preferably 1 to 10, more preferably 1 to 7, even more preferably 1 to 6, particularly preferably 1 to 5, and most preferably 1 to 4 carbon atoms, said alkyl groups may be linear, branched, cyclic, saturated or unsaturated, most preferably linear, saturated alkyl groups; -R ３ is selected from the group consisting of alkyl groups having 1 to 12, preferably 1 to 10, more preferably 1 to 7, even more preferably 1 to 6, particularly preferably 1 to 5, and most preferably 1 to 4 carbon atoms, aryl groups having 6 to 14, preferably 6 to 12, and most preferably 6 to 10 carbon atoms, and aralkyl groups having 7 to 14, preferably 7 to 12, and most preferably 7 to 10 carbon atoms, said alkyl groups may be linear, branched, cyclic, saturated or unsaturated, and are most preferably linear; -R ４ is selected from the group consisting of alkyl groups having 3 to 12, preferably 3 to 10, more preferably 3 to 7, and most preferably 4 to 6 carbon atoms, aryl groups having 6 to 14, preferably 6 to 12, and most preferably 6 to 10 carbon atoms, and aralkyl groups having 7 to 14, preferably 7 to 12, and most preferably 7 to 10 carbon atoms, said alkyl groups may be linear, branched, cyclic, saturated or unsaturated, and are most preferably linear and saturated; X is selected from the group consisting of halides, preferably chloride and / or bromide, hydrogen sulfate, alkyl sulfate, preferably methyl sulfate and ethyl sulfate, carbonate, hydrogen carbonate, acetate or hydroxide; 7. The method according to claim 6.

8. R １ ~R ４ is selected so that the total number of carbon atoms in said quaternary ammonium cation is 6 to 14, preferably 7 to 14, more preferably 8 to 13; or R １ ~R ４ is selected so that the total of carbon atoms in said quaternary ammonium cation is from 15 to 30, preferably from 15 to 28, more preferably from 15 to 24, even more preferably from 16 to 22, and most preferably from 16 to 20.

9. R １ ~R ４ and X is selected so that the total number of carbon atoms in said quaternary ammonium salt is 6 to 14, preferably 7 to 14, more preferably 8 to 13; or R １ ~R ４ and X is selected such that the total number of carbon atoms in said quaternary ammonium salt is from 15 to 30, preferably from 15 to 28, more preferably from 15 to 24, even more preferably from 16 to 22, and most preferably from 16 to 20.

10. The polyisocyanurate is a) OH group, SH group, NH group, NH ２ a polyester polyol or a mixture of polyester polyols or a mixture of polyester polyols and polyether polyols, containing isocyanate-reactive groups, preferably OH groups, selected from groups and mixtures thereof, b) an excess of one or more isocyanates selected from the group consisting of organic isocyanates, mixtures of organic isocyanates, organic polyisocyanates, mixtures of organic polyisocyanates, and mixtures of organic isocyanate(s) and organic polyisocyanate(s); c) a catalyst that catalyzes the reaction of said isocyanate-reactive groups with said isocyanate groups and / or with each other, provided that at least one trimerization catalyst is included. d) optionally, a foam stabilizer e) optionally, a propellant f) Optionally, further additives The method according to any one of claims 1 to 9, characterized in that the compound is produced by reacting in the presence of

11. The polyester polyol is one or more aromatic or aliphatic carboxylic acids or mixtures of aromatic and aliphatic carboxylic acids, said carboxylic acids having 2 or 3, more preferably 2, carboxylic acid groups and having from 2 to 12, preferably from 4 to 10, more preferably from 6 to 10 carbon atoms per molecule, A polyol or a mixture of polyols, at least one of which contains OH, SH, NH, NH groups. ２ 11. The method according to any one of claims 1 to 10, characterized in that the polyol or mixture of polyols has two or more isocyanate-reactive groups, preferably OH groups, selected from the group consisting of groups consisting of OH groups and mixtures thereof, and the polyol or mixture of polyols has in total an average of 1.8 to 8, preferably 1.9 to 5, more preferably 2 to 3 and most preferably 2, said isocyanate-reactive groups, and the polyol(s) has an average of 2 to 12, preferably 2 to 10, more preferably 2 to 6 carbon atoms, and the polyol(s) may comprise ether and / or carbonate functional groups, preferably polyether polyols or polyether carbonate polyols.

12. The aromatic carboxylic acid is selected from the group consisting of phthalic acid, preferably (ortho)-phthalic acid, isophthalic acid, terephthalic acid and the isomeric naphthalenedicarboxylic acids. and / or The aliphatic carboxylic acid is selected from the group consisting of succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, and fumaric acid.

12. The method according to claim 11 .

13. 13. The method according to any one of claims 1 to 12, characterized in that at least 90% by weight, preferably at least 95% by weight, more preferably at least 98% by weight of the polyol component used to prepare the polyisocyanurate is a polyester polyol having a hydroxyl number of 100 to 450 mg KOH / g, preferably 120 to 400 mg KOH / g, more preferably 140 to 350 mg KOH / g.

14. 14. The method according to any one of claims 1 to 13, characterized in that the organic isocyanate and / or polyisocyanate(s) is / are selected from the group consisting of monomeric, oligomeric or polymeric, aliphatic, cycloaliphatic, arylaliphatic or aromatic isocyanates having two or more, preferably two to four, isocyanate groups and mixtures thereof.

15. 15. The method of claim 14, wherein the polyisocyanurate has an isocyanate index of 150 or more, preferably >180, more preferably >250, most preferably >250-500.

16. the one or more carboxylic acids obtained after the hydrolysis are selected from the group consisting of phthalic acid, preferably (ortho)-phthalic acid, isophthalic acid, terephthalic acid and the isomeric naphthalenedicarboxylic acids, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decanedicarboxylic acid, maleic acid, fumaric acid and mixtures thereof, and / or the one or more polyols obtained after the hydrolysis are diols based on glycols and / or glycol ethers, particularly preferably monoethylene glycol and / or diethylene glycol, having a molecular weight of less than 180 g / mol, preferably less than 140 g / mol; and / or The one or more organic amines and / or polyamines obtained after the hydrolysis are selected from the group consisting of dodecane 1,12-diamine, 2-ethyltetramethylene 1,4-diamine, 2-methylpentamethylene 1,5-diamine, tetramethylene 1,4-diamine, pentamethylene diamine (PDA) and preferably hexamethylene 1,6-diamine (HMDA), cyclohexane 1,3- and 1,4-diamine and any mixtures of their isomers, 4,4'-methylenedicyclohexyl diisocyanate (H12MDI), 1-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl silane (MDI), methyl ... cycloaliphatic diamines such as cyclohexane (isophoronediamine or IPDA for short), hexahydrotolylene 2,4- and 2,6-diamine and the corresponding isomeric mixtures, and preferably aromatic diamines and polyamines, for example toluene 2,4- and 2,6-diamine (TDA) and the corresponding isomeric mixtures, naphthalenediamine, diethyltoluenediamine, mixtures of diphenylmethane 4,4', 2,4'- and 2,2'-diamine (MDA) and polyphenylpolymethylenepolyamines and their more highly condensed analogues having an average functionality of 2 to 4. The method according to any one of claims 1 to 15, characterized in that

17. the reaction products of the hydrolysis are separated from one another and optionally purified; 17. The method according to any one of claims 1 to 16, characterized in that the preferred separation and purification methods are selected from the group consisting of filtration, membrane separation, phase separation, chromatographic methods, distillation, extraction and combinations of said methods.

18. The polyisocyanurate is foamed, preferably a rigid foam. The method according to any one of claims 1 to 17, characterized in that

19. the polyisocyanurate with water and the organic amine base, or with water, the organic amine and the phase transfer catalyst; At a temperature of 80°C to 220°C, preferably 100°C to 200°C, more preferably 120°C to 190°C, most preferably 140°C to 180°C and / or 1 minute to 48 hours, preferably 1 minute to 40 hours, more preferably 5 minutes to 35 hours, even more preferably 10 minutes to 30 hours, particularly preferably 20 minutes to 24 hours, very preferably 30 minutes to 18 hours, most preferably 30 minutes to 16 hours and / or At atmospheric pressure or at a pressure of 1 to 30 bar, 2 to 20 bar, more preferably 3 to 15 bar The method according to any one of claims 1 to 18, characterized in that the method comprises contacting.

20. 20. The method according to any one of claims 2 to 19, characterized in that at least 0.5 weight percent of catalyst is used, more preferably 0.5 to 15 weight percent, even more preferably 1 to 10 weight percent, especially more preferably 1 to 8 weight percent, very preferably 1 to 7 weight percent, and most preferably 2 to 6 weight percent, based on the weight of the polyisocyanurate.

21. 21. The method according to any one of claims 1 to 20, characterized in that the weight ratio of the sum of the organic amine base to the polyisocyanurate is in the range of from 1:100 to 50:1, preferably from 1:50 to 25:1, more preferably from 1:10 to 20:1, even more preferably from 1:5 to 10:1, and most preferably from 1:2 to 3:

1.

22. 22. The method according to any one of claims 1 to 21, wherein the hydrolysis results in a cleavage rate of existing isocyanurate groups of more than 85%, preferably more than 90%, particularly preferably more than 95%, even more preferably 100%.

23. 23. Use of one or more carboxylic acids and / or polyols and / or organic amines and / or polyamines obtainable by the process according to any one of claims 1 to 22 for the production of new chemical entities, preferably polyurethanes, preferably polyurethane foams, or polyisocyanurates, preferably polyisocyanurate foams.

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