Dispersant for producing polyol dispersions from polyurethane waste and use thereof

Abstract

The invention relates to dispersants obtained by polymerizing ethylenically unsaturated acids or anhydrides onto mercapto-functionalized polyether polyols, to the use thereof for producing polyol dispersions by acidolysis of polyurethane waste, and to the use of the resulting polyol dispersions for producing polyurethanes.

Description

Technical Field

[0001] The present invention relates to polymers obtained by polymerizing ethylenically unsaturated acids or anhydrides onto mercapto-functionalized polyether polyols, to their use for producing polyol dispersions by acid hydrolysis of polyurethane waste, and to the use of the resulting polyol dispersions for producing polyurethanes. Background Art

[0002] Very large amounts of polyurethane waste from the post-consumer industry (mattresses, car seats, sofas, cushions, interior decoration, etc.) are disposed of every year. Furthermore, during the processing of polyurethane slabstock foam, polyurethane waste is also generated which sometimes has to be disposed of.

[0003] It is therefore desirable to recover these materials as far as possible and return them to the raw material loop in an ecological and economical way.

[0004] Chemical conversion of polyurethanes by water (hydrolysis), amines (ammonolysis), alcohols (alcoholysis), and acids or anhydrides (acidolysis) has been proposed to convert polyurethanes into recycled polyols.

[0005] DE 19512778 C1 relates to the acidolysis of polyurethane waste with dicarboxylic acids or anhydrides. This document discloses the use of polyether polyols grafted with ethylenically unsaturated monomers containing carbonyl groups in order to obtain stable polyol dispersions.

[0006] DE 102013106364 A1 also discloses the acid hydrolysis of polyurethane foams in the presence of grafted polyether polyols. In this document, the use of specific dual-phase steels is proposed in order to produce high-quality recycled polyols.

[0007] WO 2018 / 091568 A1 relates to a process for the acidolysis of polyurethane waste, wherein the resulting polyols are subjected to a reaction with short-chain diols or triols to increase their hydroxyl number and reduce their acid number.

[0008] Mercapto-functional polyether polyols grafted with ethylenically unsaturated monomers have been reported in the prior art (eg GB1031039, US4016332, EP0213701, WO9637520). However, these polyols have not been disclosed as suitable dispersants or stabilizers for producing polyols from the acidolysis of polyurethanes.

[0009] Despite the prior art disclosures of methods for preparing recycled polyols, there is still room for improvement. In this regard, further efficient methods for preparing polyol dispersions from waste polyurethanes are desired. Summary of the invention

[0010] The authors of the present invention have found that polymers obtained by (i) functionalizing some of the hydroxyl groups of a polyether polyol with mercapto-containing groups to provide mercapto-terminated polyols and (ii) grafting an ethylenically unsaturated acid or anhydride onto the mercapto-terminated polyols can be advantageously used as dispersants or stabilizers for (recycled) polyols obtained by acidolysis of (waste) polyurethanes.

[0011] In fact, as disclosed in the prior art, it has been found that these polymers provide polyol dispersions with improved particle size and / or viscosity compared to polyol dispersions obtained by acid hydrolysis of polyurethanes using polymers produced by direct grafting of ethylenically unsaturated acids onto polyether polyols (without prior functionalization with mercapto groups). For the subsequent use of these polyol dispersions as raw materials for the preparation of polyurethanes, they exhibit very good stability and particle size.

[0012] For the subsequent use of the obtained polyol dispersion in the manufacture of new polyurethanes, in addition to very good stability and particle size, it also has a suitable (low) viscosity. In particular, the viscosity allows it to be subsequently handled, pumped and blended with other components to prepare new polyurethanes. In contrast, when polyol dispersions with very high viscosities are obtained, they do not have suitable processability for their use in the industrial manufacture of polyurethanes. In addition, since it is not necessary to further dilute the polyol dispersion to achieve a viscosity suitable for its processability when manufacturing polyurethanes, this will allow the incorporation of larger amounts of recovered polyols in new polyurethanes.

[0013] Furthermore, it has been found that the polymers of the present invention are very effective dispersants for polyols of this type and can therefore be used in very low amounts during the acid hydrolysis process. Thus, they provide a very efficient and economical method for recycling large amounts of polyurethane into stable polyol dispersions using small amounts of dispersants.

[0014] In particular, it has been found that even when the polymer of the present invention is used as a dispersant in an amount of about 2% by weight based on the total mass of all components (starting materials) used in the acidolysis, a stable polyol dispersion is obtained. In contrast, DE 19512778 C1 and WO 2018 / 091568 A1 disclose the use of a dispersant (non-thiol functionalized before grafting) in an amount of greater than 20% by weight based on the total mass of all components used in the acidolysis. This large amount of dispersant increases the process costs and also greatly reduces the amount of polyurethane waste that can be recovered per reaction, which results in a less economical process.

[0015] Thus, in a first aspect, the invention relates to the use of a polymer according to the invention as a dispersant or stabilizer in the acid hydrolysis of polyurethanes.

[0016] In a second aspect, the invention relates to the use of a polymer according to the invention for preparing a polyol dispersion by acidolysis of a polyurethane.

[0017] The polymer of the present invention is a polymer obtainable by a process comprising:

[0018] i) reacting a polyether polyol having a hydroxyl functionality of 2 to 6 and a number average molecular weight of 300 Da to 15,000 Da with a compound of formula (I) at a molar ratio of the compound of formula (I) to the polyether polyol of 0.05:1 to x:1 to provide a mercapto-functionalized polyether polyol, wherein x is the hydroxyl functionality of the polyether polyol minus 1,

[0019]

[0020] in

[0021] R 1 Selected from H and linear or branched C1 to C 10 Alkyl, and

[0022] R 2 It is a linear or branched C1 to C 10 Alkylene; and

[0023] ii) reacting a mercapto-functional polyether polyol with an ethylenically unsaturated acid or anhydride monomer in the presence of a free radical initiator.

[0024] In a third aspect, the present invention relates to a process for producing a polyol dispersion from a polyurethane, wherein the process comprises reacting a polyurethane with a dicarboxylic acid or anhydride in the presence of a polymer of the present invention at a temperature of 150°C to 250°C.

[0025] In a fourth aspect, the present invention relates to a polyol dispersion obtainable by the process defined in the third aspect.

[0026] In a fifth aspect, the present invention relates to the use of the polyol dispersion according to the fourth aspect for the manufacture of polyurethane.

[0027] In a sixth aspect, the present invention relates to a process for preparing a polyurethane comprising reacting the polyol dispersion according to the fourth aspect with a polyisocyanate.

[0028] In another aspect, the present invention relates to a polyurethane obtainable by the process of the seventh aspect.

[0029] In another aspect, the present invention relates to a polymer obtainable by a process comprising:

[0030] i) reacting a polyether polyol having a hydroxyl functionality of 3 to 6 and a number average molecular weight of 3,000 Da to 15,000 Da with a compound of formula (I) at a molar ratio of the compound of formula (I) to the polyether polyol of 0.05:1 to x:1 to provide a mercapto-functionalized polyether polyol, wherein x is the hydroxyl functionality of the polyether polyol minus 1,

[0031]

[0032] in

[0033] R 1 Selected from H and linear or branched C1 to C 10 Alkyl, and

[0034] R 2 It is a linear or branched C1 to C 10 Alkylene; and

[0035] ii) reacting a mercapto-functional polyether polyol with an ethylenically unsaturated acid or anhydride monomer in the presence of a free radical initiator. DETAILED DESCRIPTION

[0036] Unless otherwise defined, all technical terms and scientific terms used herein have the same meanings as those generally understood by those of ordinary skill in the art to which the present disclosure belongs. As used herein, nouns modified with quantifiers represent one / kind and more / kind unless the context clearly indicates otherwise.

[0037] The terms "comprising", "including" and variations thereof encompass the terms "consisting essentially of" and "consisting of. Therefore, each time the terms "comprising", "including" and variations thereof appear in this application, they may be replaced with the terms "consisting essentially of" and "consisting of.

[0038] When a range is indicated in this document, both the lower limit and the upper limit are included in the stated range.

[0039] When the amount of a component is given by a range with a lower limit of 0 or 0.0, this means that the component may not be present, or it may be present in an amount not higher than the specified upper limit of the range.

[0040] As used herein, the term "wt%" means weight-weight percentage (w / w).

[0041] As used herein, the term "mol %" means mole-to-mole percent (mol / mol).

[0042] When the amount or ratio of a specific component is disclosed herein, the amount or ratio is based on the total amount of the component. For example, if a mixture of two or more ethylenically unsaturated acids or anhydrides is used, the amount or ratio of the ethylenically unsaturated acid or anhydride disclosed herein is based on the total amount of all ethylenically unsaturated acids or anhydrides used.

[0043] The skilled person will readily appreciate that when a composition is defined by weight percentage values ​​of all the components it comprises, these values ​​can never add up to a value greater than 100%. The composition comprises all components in amounts that add up to 100% by weight of the composition.

[0044] For the purpose of the present invention, the expressions "available", "obtained" and equivalent expressions are used interchangeably, and in any case, the expression "available" encompasses the expression "obtained".

[0045] Unless otherwise specifically stated, or unless all embodiments disclosed in connection with one aspect of the present invention are clearly incompatible with other aspects, all embodiments disclosed in connection with one aspect of the present invention are also applicable to other aspects. In addition, unless otherwise stated herein or otherwise clearly contradictory to the context, the present invention encompasses any combination of the embodiments and preferred embodiments described herein.

[0046] It will be understood that the scope of the present disclosure includes all possible combinations of the embodiments disclosed herein belonging to the same aspect of the invention or belonging to different aspects of the invention.

[0047] The polymer of the present invention can be obtained by a process comprising:

[0048] i) reacting a polyether polyol having a hydroxyl functionality of 2 to 6 and a number average molecular weight of 300 Da to 15,000 Da with a compound of formula (I) in a molar ratio of compound of formula (I):polyether polyol of 0.05:1 to x:1, wherein x is the hydroxyl functionality of the polyether polyol minus 1,

[0049]

[0050] in

[0051] R 1 selected from H and linear or branched C1 to C 10 Alkyl, and

[0052] R 2 It is a linear or branched C1 to C 10 Alkylene; and

[0053] ii) reacting the resulting mercapto-functionalized polyether polyol with an ethylenically unsaturated acid or anhydride monomer in the presence of a free radical initiator.

[0054] In one aspect, the invention relates to a polymer of the invention obtained by a process comprising:

[0055] i) reacting a polyether polyol having a hydroxyl functionality of 3 to 6 and a number average molecular weight of 3,000 Da to 15,000 Da with a compound of formula (I) in a molar ratio of compound of formula (I):polyether polyol of 0.05:1 to x:1, wherein x is the hydroxyl functionality of the polyether polyol minus 1,

[0056]

[0057] in

[0058] R 1 Selected from H and linear or branched C1 to C 10 Alkyl, and

[0059] R 2 It is a linear or branched C1 to C 10 Alkylene; and

[0060] ii) reacting the resulting mercapto-functionalized polyether polyol with an ethylenically unsaturated acid or anhydride monomer in the presence of a free radical initiator.

[0061] Unless expressly stated otherwise, or unless they are clearly incompatible, the following embodiments relating to the polymers of the invention apply to all aspects of the invention.

[0062] The polyether polyols used to prepare the polymers of the present invention are polyols having ether groups within the polymer chain, having a hydroxyl functionality of 2 to 6 and a number average molecular weight of 300 Da to 15,000 Da, also commonly referred to as polyalkylene polyether polyols.

[0063] In one embodiment, the polyether polyol is the product of polymerization of an alkylene oxide having 2 to 4 carbon atoms (eg, ethylene oxide, propylene oxide, butylene oxide, and mixtures thereof) in the presence of a starting compound having 2 to 6 active hydrogen atoms.

[0064] Suitable starting compounds for obtaining polyether polyols include, for example, polyhydroxy compounds such as ethylene glycol, propylene glycol, 1,3-dihydroxypropane, 1,3-dihydroxybutane, 1,4-dihydroxybutane, 1,4-dihydroxyhexane, 1,5-dihydroxyhexane, 1,6-dihydroxyhexane, 1,2-dihydroxyoctane, 1,3-dihydroxyoctane, 1,4-dihydroxyoctane, 1,6-dihydroxyoctane, 1,8-dihydroxyoctane, 1,10-dihydroxydecane, 1,2,4-trihydroxybutane, 1,2,6-trihydroxyhexane, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol, sorbitol, pentaerythritol, xylitol, arabitol, mannitol, glucose, sucrose, etc. Suitable polyether polyols can be formed by alkoxylation of the starting materials. The alkoxylation reaction can be catalyzed using any conventional catalyst including, for example, potassium hydroxide or a double metal cyanide (DMC) catalyst.

[0065] Thus, polyether polyols suitable for preparing the polymers of the present invention include ethylene glycol, propylene glycol, 1,3-dihydroxypropane, 1,3-dihydroxybutane, 1,4-dihydroxybutane, 1,4-dihydroxyhexane, 1,5-dihydroxyhexane, 1,6-dihydroxyhexane, 1,2-dihydroxyoctane, 1,3-dihydroxyoctane, 1,4-dihydroxyoctane, 1,6-dihydroxyoctane, 1,8-dihydroxyoctane, 1,10-dihydroxydecane, 1,2,4-trihydroxybutane, 1,2,6-trihydroxyhexane, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol, sorbitol, pentaerythritol, xylitol, arabitol, mannitol, alkylene oxide adducts of glucose, sucrose, and the like; in particular, adducts of alkylene oxides having 2 to 4 carbon atoms.

[0066] According to one embodiment, when the polyether polyol is a product of polymerization of two or more, for example two or three, alkylene oxides, the alkylene oxides may be added simultaneously or sequentially so that the polyether polyol has inner blocks, terminal blocks or random distribution of different oxyalkylene groups.

[0067] Examples of suitable polyether polyols include: polyoxyethylene diol, polyoxyethylene triol, polyoxyethylene tetrol, polyoxyethylene pentol, and polyoxyethylene hexol; polyoxypropylene diol, polyoxypropylene triol, polyoxypropylene tetrol, polyoxypropylene pentol, and polyoxypropylene hexol; and mixtures thereof.

[0068] When a mixture of ethylene oxide and propylene oxide is used to produce the polyether polyol, the ethylene oxide and propylene oxide may be added simultaneously or sequentially so that the polyether polyol has internal blocks, terminal blocks or random distribution of oxyethylene and / or oxypropylene groups.

[0069] In one embodiment, the polyether polyol is composed of propylene oxide units, ethylene oxide units or mixtures thereof. That is, the polymer part of the polyether polyol (i.e. excluding the starting compound) consists only of propylene oxide units, ethylene oxide units or mixtures thereof. Therefore, it is poly(ethylene oxide and / or propylene oxide).

[0070] In another embodiment, the polyether polyol is composed of propylene oxide units and ethylene oxide units; that is, it is a propylene oxide-ethylene oxide copolymer. In one embodiment, the polyether polyol is a random or block propylene oxide-ethylene oxide copolymer with or without ethylene oxide terminal (end) groups.

[0071] In another embodiment, the polyether polyol is a propylene oxide polymer having ethylene oxide terminal groups.

[0072] Thus, the polyether polyol may be a propylene oxide homopolymer or an ethylene oxide homopolymer, or a random or block propylene oxide-ethylene oxide copolymer with or without ethylene oxide terminal groups.

[0073] In a particular embodiment, the polyether polyol is a poly(ethylene oxide and / or propylene oxide) adduct of a polyol, in particular the polyol is selected from the group consisting of ethylene glycol, propylene glycol, 1,3-dihydroxypropane, 1,3-dihydroxybutane, 1,4-dihydroxybutane, 1,4-dihydroxyhexane, 1,5-dihydroxyhexane, 1,6-dihydroxyhexane, 1,2-dihydroxyoctane, 1,3-dihydroxyoctane, 1,4-dihydroxyoctane, 1,6-dihydroxyoctane, 1,8-dihydroxyoctane, 1,10-dihydroxydecane, glycerol, sorbitol, 1,1,1-trimethylolpropane, 1,2,4-trihydroxybutane, 1,2,6-trihydroxyhexane, 1,1,1-trimethylolethane, pentaerythritol, xylitol, arabitol, mannitol, glucose and sucrose; more particularly, selected from the group consisting of glycerol and sorbitol.

[0074] In one embodiment, the polyether polyol is composed of propylene oxide monomers and 0 to 95 wt %, or even 0 to 75 wt %, of ethylene oxide monomers, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether polyol is composed of propylene oxide and 0 to 50 wt %, or even 0 to 30 wt %, of ethylene oxide, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether is a propylene oxide homopolymer, i.e., the polyether is composed of propylene oxide units or monomers.

[0075] In another embodiment, the polyether polyol is composed of ethylene oxide monomers and 0 to 95 wt %, or even 0 to 75 wt %, of propylene oxide monomers, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In another embodiment, the polyether polyol is composed of ethylene oxide and 0 to 50 wt %, or even 0 to 30 wt %, of propylene oxide, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether polyol is an ethylene oxide homopolymer, i.e., the polyether polyol is composed of ethylene oxide units or monomers.

[0076] In one embodiment, the polyether polyol is composed of propylene oxide and ethylene oxide, and contains 5% to 95% by weight of propylene oxide monomers and 5% to 95% by weight of ethylene oxide monomers, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether polyol is composed of propylene oxide and ethylene oxide, and contains 5% to 50% by weight, or even 8% to 30% by weight of ethylene oxide, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In a specific embodiment, the polyether polyol is a propylene oxide polymer containing 5% to 50% by weight, or even 8% to 30% by weight of polyethylene oxide end groups, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In another embodiment, the polyether polyol is a propylene oxide adduct of glycerol or sorbitol containing 5 to 50 wt %, or even 8 to 30 wt % of polyethylene oxide end groups, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In some embodiments, the ethylene oxide content in the poly(ethylene oxide and propylene oxide) polymer is 10 to 25 wt %, based on the weight of the monomers. The ethylene oxide and propylene oxide content can be determined, for example, by 13 C-NMR confirmed.

[0077] The hydroxyl functionality of the polyether polyol may be 2, 3, 4, 5 or 6. In one embodiment, it has a functionality of 3 to 6, for example a functionality of 3 or 6. In a particular embodiment, it has a functionality of 3. In another embodiment, it has a functionality of 6.

[0078] According to one embodiment, the polyether polyol has a molecular weight ranging from 1,000 Da to 15,000 Da, or even from 2,000 Da to 15,000 Da. In one embodiment, its molecular weight ranges from 3,000 Da to 14,000 Da, or even from 4,000 Da to 13,000 Da.

[0079] In other embodiments, the hydroxyl number of the polyether polyol is in the range of 15 mgKOH / g to 100 mgKOH / g, or even 20 mgKOH / g to 60 mgKOH / g.

[0080] According to some specific embodiments, the viscosity of the polyether polyol is from 200 mPa s to 8,000 mPa s. In other embodiments, its viscosity is from 400 mPa s to 5,000 mPa s, or even from 500 mPa s to 2,000 mPa s.

[0081] In a particular embodiment, the polyether polyol has a hydroxyl functionality of 3 to 6 and a molecular weight of 2,000 Da to 15,000 Da.

[0082] According to one embodiment, the polyether polyol is a poly(ethylene oxide and / or propylene oxide) polymer having a hydroxyl functionality of 3 to 6.

[0083] In another embodiment, the polyether polyol is a poly(ethylene oxide and / or propylene oxide) polymer having a hydroxyl functionality of 3 to 6 and a molecular weight of 3,000 Da to 15,000 Da.

[0084] In a particular embodiment, the polyether polyol is a poly(ethylene oxide and / or propylene oxide) adduct having a hydroxyl number of 15 to 100 mgKOH / g selected from the group consisting of glycerol, sorbitol, 1,1,1-trimethylolpropane, 1,2,4-trihydroxybutane, 1,2,6-trihydroxyhexane, 1,1,1-trimethylolethane, pentaerythritol, xylitol, arabitol, mannitol, glucose and sucrose.

[0085] In the compound of formula (I), R 2 is a linear or branched alkylene group, i.e. a linear or branched saturated divalent hydrocarbon chain having 1 to 10 carbon atoms. The term hydrocarbon chain refers to a chain radical consisting of hydrogen atoms and carbon atoms. In a specific embodiment, R 2 is a C1-C6 linear or branched alkylene group. 2 is a C1-C4 linear or branched alkylene group, such as a methylene group, an ethylene group, a propylene group or a butylene group.

[0086] In one embodiment, R 1 is selected from H and linear or branched C1-C6 alkyl, or is selected from H and linear or branched C1-C4 alkyl, for example methyl, ethyl, propyl or butyl.

[0087] In a particular embodiment, the compound of formula (I) is selected from 2-mercaptoacetic acid, 2-mercaptopropionic acid, 3-mercaptopropionic acid, 2-mercaptobutyric acid, 3-mercaptobutyric acid, 4-mercaptobutyric acid, 2-mercapto-4-methyl-pentanoic acid, 2-mercaptopentanoic acid, 3-mercaptopentanoic acid, 5-mercaptopentanoic acid, 6-mercaptohexanoic acid, 7-mercaptoheptanoic acid, 8-mercaptooctanoic acid, 9-mercaptononanoic acid, 10-mercaptodecanoic acid, 3-mercapto-2-(mercaptomethyl)propionic acid and C1-C 10 Alkyl, preferably C1-C6 alkyl, its esters such as methyl 2-mercaptoacetate, ethyl 2-mercaptoacetate or propyl 2-mercaptoacetate, methyl 2-mercaptopropionate, ethyl 2-mercaptopropionate, or propyl 2-mercaptopropionate, methyl 3-mercaptopropionate, ethyl 3-mercaptopropionate, or propyl 3-mercaptopropionate, methyl 2-mercaptobutyrate, ethyl 2-mercaptobutyrate, or propyl 2-mercaptobutyrate, methyl 3-mercaptobutyrate, ethyl 3-mercaptobutyrate, or propyl 3-mercaptobutyrate, methyl 4-mercaptobutyrate, ethyl 4-mercaptobutyrate, or propyl 4-mercaptobutyrate and mixtures thereof.

[0088] According to one embodiment, the compound of formula (I) is selected from 2-mercaptoacetic acid, 2-mercaptopropionic acid and 3-mercaptopropionic acid. In a specific embodiment, the compound of formula (I) is 2-mercaptoacetic acid. In another embodiment, the compound of formula (I) is 3-mercaptopropionic acid.

[0089] The mercapto-functionalized polyether polyol obtained after step i) retains one or more non-functionalized hydroxyl (-OH) groups on average, which is particularly suitable. Therefore, the molar ratio of the compound of formula (I) to the polyether polyol in step i) is from 0.05:1 to x:1, wherein x is the hydroxyl functionality of the polyether polyol minus 1 (f-1).

[0090] In a particular embodiment, the molar ratio of the compound of formula (I) to the polyether polyol in step i) is from 0.1:1 to x:1, or even from 0.5:1 to x:1. In another embodiment, it is from 0.8:1 to x:1, wherein x is the hydroxyl functionality of the polyether polyol minus 1. In another embodiment, the ratio is from 1:1 to x:1.

[0091] In one particular embodiment, x is the hydroxyl functionality of the polyether polyol minus 1.5.

[0092] According to one embodiment, the molar ratio of the compound of formula (I) to the polyether polyol in step i) is from 0.05:1 to 4:1, or even from 0.1:1 to 3:1 (provided that it is equal to or less than x:1, x being the hydroxyl functionality of the polyether polyol minus 1). In another embodiment, the molar ratio is from 0.5:1 to 3:1, or even from 0.8:1 to 3:1 (provided that it is equal to or less than x:1, x being the hydroxyl functionality of the polyether polyol minus 1). In another embodiment, the ratio is from 1:1 to 3:1.

[0093] According to one embodiment, the molar ratio of the compound of formula (I) to the polyether polyol in step i) is from 0.05:1 to 2:1, or even from 0.1:1 to 2:1 (provided that it is equal to or less than x:1, x is the hydroxyl functionality of the polyether polyol minus 1). In another embodiment, the molar ratio is from 0.5:1 to 1.8:1, or even from 0.8:1 to 1.5:1 (provided that it is equal to or less than x:1, x is the hydroxyl functionality of the polyether polyol minus 1).

[0094] In a particular embodiment, when the functionality of the polyether polyol is 2, the molar ratio of compound of formula (I):polyether polyol is from 0.05:1 to 1:1. In another embodiment, it is from 0.05:1 to 0.8:1, or even from 0.1:1 to 0.8:1. In another embodiment, it is from 0.5:1 to 1:1, or even from 0.5:1 to 0.8:1.

[0095] In a particular embodiment, when the functionality of the polyether polyol is 3, the molar ratio of compound of formula (I):polyether polyol is from 0.05:1 to 2:1, or from 0.1:1 to 2:1. In another embodiment, it is from 0.05:1 to 1.5:1, or even from 0.05:1 to 1.3:1. In one embodiment, it is from 0.1:1 to 1.5:1, or even from 0.1:1 to 1.3:1. In another embodiment, it is from 0.5:1 to 2:1, or even from 0.5:1 to 1.5:1. According to a particular embodiment, the ratio is from 0.8:1 to 1.5:1.

[0096] In a particular embodiment, when the functionality of the polyether polyol is 4, the molar ratio of compound of formula (I):polyether polyol is from 0.05:1 to 3:1, or from 0.1:1 to 3:1. In another embodiment, it is from 0.05:1 to 2.5:1, or even from 0.05:1 to 2:1. In one embodiment, it is from 0.1:1 to 2.5:1, or even from 0.1:1 to 2:1. In another embodiment, it is from 0.5:1 to 3:1, or even from 0.5:1 to 2.5:1. According to a particular embodiment, the ratio is from 0.8:1 to 2.5:1.

[0097] In a particular embodiment, when the functionality of the polyether polyol is 5, the molar ratio of compound of formula (I):polyether polyol is from 0.05:1 to 4:1, or from 0.1:1 to 4:1. In another embodiment, it is from 0.05:1 to 3:1, or even from 0.05:1 to 2:1. In one embodiment, it is from 0.1:1 to 3:1, or even from 0.1:1 to 2:1. In another embodiment, it is from 0.5:1 to 4:1, or even from 0.5:1 to 3:1. According to a particular embodiment, the ratio is from 0.8:1 to 3:1.

[0098] In a particular embodiment, when the functionality of the polyether polyol is 6, the molar ratio of compound of formula (I): polyether polyol is from 0.05:1 to 5:1, or from 0.1:1 to 5:1. In another embodiment, it is from 0.05:1 to 4:1, or even from 0.05:1 to 3:1. In one embodiment, it is from 0.1:1 to 4:1, or even from 0.1:1 to 3:1. In another embodiment, it is from 0.05:1 to 2:1. In another embodiment, it is from 0.5:1 to 5:1, or even from 0.5:1 to 3:1. According to a particular embodiment, the ratio is from 0.8:1 to 3:1.

[0099] In a particular embodiment, when the functionality of the polyether polyol is 6, the molar ratio of compound of formula (I): polyether polyol is from 1: 1 to 5: 1. In another embodiment, it is from 1.5: 1 to 4: 1, or even from 2: 1 to 4: 1. In another embodiment, it is from 1: 1 to 4: 1, or even from 1: 1 to 3: 1.

[0100] The reaction between the polyether polyol and the compound of formula (I) in step i) can be carried out by means known in the art. In one embodiment, step i) is carried out in the presence of a catalyst, for example in an amount of 0.5 mol% to 30 mol%, or even 1 mol% to 10 mol%, relative to the polyether polyol, to accelerate the esterification reaction between the hydroxyl groups in the polyether polyol and the carboxylic acid groups or ester groups in the compound of formula (I).

[0101] Suitable esterification catalysts include sulfuric acid, p-toluenesulfonic acid, methanesulfonic acid, phosphoric acid, tin oxides (e.g. di(n-butyl)tin oxide, n-butyltin acid), phosphorus oxides, tin alkanoates (e.g. tin dioctoate, tin di-(2-ethylhexanoate), butyltin tri-(2-ethylhexanoate), tin tetraoctoate, tin tetra(2-ethylhexanoate), tetraalkyl titanate / ester (e.g. tetra(n-butyl) titanate, tetra(isopropyl) titanate). In one embodiment, the catalyst is an acid catalyst, such as sulfuric acid or p-toluenesulfonic acid. In a particular embodiment, step i) is carried out in the presence of sulfuric acid, preferably concentrated sulfuric acid, as a catalyst.

[0102] Step i) may be carried out at a temperature of 50°C to 200°C, such as 100°C to 150°C.

[0103] The reaction of the polyether polyol with the compound of formula (I) in step i) can be carried out for 0.5 to 24 hours, or even for 2 to 24 hours. In a particular embodiment, step i) is carried out for 3 to 15 hours, or even for 5 to 10 hours.

[0104] The reaction in step i) can be carried out in the presence of a solvent or diluent, such as monoalcohols (ie, monohydric alcohols), polyols, hydrocarbons, ethers and mixtures thereof. In a particular embodiment, the reaction is carried out without adding a solvent or diluent.

[0105] The reaction in step i) can be carried out under vacuum to remove by-products of the reaction (e.g., water). In another embodiment, the reaction in step i) can be carried out under azeotropic distillation conditions, e.g., in the presence of toluene, so that the water produced in the reaction is removed by azeotropic distillation with toluene.

[0106] After step i), a thiol-functionalized (or thiol-terminated) polyether polyol is obtained. According to some specific embodiments, the viscosity of the thiol-functionalized polyether polyol is 500 mPa s to 8,000 mPa s. In other embodiments, its viscosity is 500 mPa s to 5,000 mPa s, or even 500 mPa s to 3,000 mPa s.

[0107] In a particular embodiment, the thiol-functionalized polyether polyol contains on average 0.05 to 4.0 moles of thiol groups per mole of thiol-functionalized polyether polyol (provided that the value is equal to or less than x, where x is the hydroxyl functionality of the starting polyether polyol minus 1); i.e., the starting polyether polyol is reacted with 0.05 to 4.0 moles of the compound of formula (I). In one embodiment, it contains on average 0.1 to 3.0 moles, or even 0.5 to 3.0 moles of thiol groups per mole of thiol-functionalized polyether polyol (provided that the value is equal to or less than x, where x is the hydroxyl functionality of the starting polyether polyol minus 1).

[0108] The amount of thiol groups associated with the thiol-functionalized polyether polyol is intended to be the average thiol group and refers to the number of moles of thiol groups per mole of the polyether polyol (by reacting with the compound of formula (I)). Thus, the amount of thiol groups substantially corresponds to the number of moles of the compound of formula (I) relative to the number of moles of polyether polyol.

[0109] The mercapto-functionalized polyether polyol obtained in step i) is then reacted with an ethylenically unsaturated acid or anhydride monomer (also referred to herein as an ethylenically unsaturated acid or anhydride) in the presence of a free radical initiator, and optionally in the presence of a diluent and / or other ethylenically unsaturated monomers different from the ethylenically unsaturated acid or anhydride monomer. Suitable ethylenically unsaturated acids or anhydrides include acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, angelic acid, tiglic acid, citraconic acid, 2,3-dimethylmaleic acid, 3-butenoic acid, itaconic acid, maleic anhydride, citraconic anhydride, 2,3-dimethylmaleic anhydride and mixtures thereof.

[0110] In one particular embodiment, the ethylenically unsaturated acid or anhydride is selected from acrylic acid, methacrylic acid, and mixtures thereof. In another embodiment, the ethylenically unsaturated acid is acrylic acid.

[0111] In one embodiment, the molar ratio of ethylenically unsaturated acid or anhydride to mercapto-functionalized polyether polyol in step ii) is from 3: 1 to 30: 1. In a specific embodiment, the molar ratio of ethylenically unsaturated acid or anhydride to mercapto-functionalized polyether polyol in step ii) is from 4: 1 to 20: 1, or even from 5: 1 to 15: 1.

[0112] According to one embodiment, the weight ratio of ethylenically unsaturated acid or anhydride to mercapto-functionalized polyether polyol in step ii) is from 0.01: 1 to 0.3: 1. In a specific embodiment, the weight ratio of ethylenically unsaturated acid or anhydride to mercapto-functionalized polyether polyol in step ii) is from 0.02: 1 to 0.3: 1, or even from 0.03: 1 to 0.2: 1.

[0113] Preferably, the molar ratio of the ethylenically unsaturated acid or anhydride in step ii) to the compound of formula (I) in step i) is equal to or greater than 2. In one embodiment, the molar ratio of the ethylenically unsaturated acid or anhydride in step ii) to the compound of formula (I) in step i) is from 2: 1 to 30: 1, or even from 3: 1 to 30: 1. In a specific embodiment, the molar ratio is from 3: 1 to 20: 1, or even from 4: 1 to 15: 1.

[0114] In addition to the ethylenically unsaturated acid or anhydride monomer, other ethylenically unsaturated monomers may be present in step ii). These other ethylenically unsaturated monomers will also polymerize together with the ethylenically unsaturated acid or anhydride in the presence of a free radical initiator.

[0115] Based on the total weight of the ethylenically unsaturated monomers present in step ii) (i.e. the total weight of the ethylenically unsaturated acid or anhydride monomers + other ethylenically unsaturated monomers), other ethylenically unsaturated monomers may be present in step ii) in an amount equal to or less than 85% by weight, or equal to or less than 70% by weight. In one embodiment, based on the total weight of the ethylenically unsaturated monomers present in step ii), they may be present in an amount equal to or less than 50% by weight, or equal to or less than 40% by weight. Therefore, in a particular embodiment, based on the total weight of the ethylenically unsaturated monomers present in step ii), step ii) comprises 0% to 85% by weight, or even 0% to 70% by weight of other ethylenically unsaturated monomers. In another embodiment, based on the total weight of the ethylenically unsaturated monomers present in step ii), step ii) comprises 0% to 50% by weight, or even 0% to 40% by weight of other ethylenically unsaturated monomers.

[0116] In step ii), the molar ratio of other ethylenically unsaturated monomers to the ethylenically unsaturated acid or anhydride may be equal to or less than 3:1, or even equal to or less than 1:1. In one embodiment, the molar ratio of other ethylenically unsaturated monomers to the ethylenically unsaturated acid or anhydride may be equal to or less than 0.5:1, or even equal to or less than 0.4:1. In a specific embodiment, step ii) comprises 0 mol% to 75 mol%, or even 0 mol% to 50 mol%, of other ethylenically unsaturated monomers, based on the total moles of ethylenically unsaturated monomers present in step ii). In another embodiment, step ii) comprises 0 mol% to 40 mol%, or even 0 mol% to 30 mol%, of other ethylenically unsaturated monomers, based on the total moles of ethylenically unsaturated monomers present in step ii).

[0117] In a particular embodiment, the only ethylenically unsaturated monomer present in step ii) is an ethylenically unsaturated acid or anhydride. That is, no other ethylenically unsaturated monomer than the ethylenically unsaturated acid or anhydride is added.

[0118] As used herein, the term "ethylenically unsaturated" refers to monomers containing ethylenic unsaturation (>C=C<, ie, two doubly bonded carbon atoms) that are capable of undergoing free radical initiated addition polymerization.

[0119] The other ethylenically unsaturated monomers may be selected from styrene, α-methylstyrene, butylstyrene, chlorostyrene, cyanostyrene, bromostyrene, methyl acrylate, methyl methacrylate, ethyl acrylate, 2-hydroxypropyl acrylate, 2-hydroxyethyl acrylate, butyl acrylate, isopropyl methacrylate, acrylonitrile, methacrylonitrile, acrylamide, methacrylamide, N,N-dimethylacrylamide, N-(dimethylaminomethyl)acrylamide, vinyl acetate, and mixtures thereof. In one embodiment, the other ethylenically unsaturated monomer is styrene.

[0120] In a particular embodiment, step ii) comprises reacting the mercapto-functionalized polyether polyol obtained in step i) with ethylenically unsaturated monomers in the presence of a free radical initiator, wherein 15% to 100% by weight of the ethylenically unsaturated monomers, or even 30% to 100% by weight of the ethylenically unsaturated monomers are ethylenically unsaturated acids or anhydrides. In a particular embodiment, 50% to 100% by weight of the ethylenically unsaturated monomers, or even 60% to 100% by weight of the ethylenically unsaturated monomers are ethylenically unsaturated acids or anhydrides.

[0121] In a particular embodiment, step ii) comprises reacting the mercapto-functionalized polyether polyol obtained in step i) with ethylenically unsaturated monomers in the presence of a free radical initiator, wherein 15 mol % to 100 mol % of the ethylenically unsaturated monomers, or even 30 mol % to 100 mol % of the ethylenically unsaturated monomers are ethylenically unsaturated acids or anhydrides. In a particular embodiment, 50 mol % to 100 mol % of the ethylenically unsaturated monomers, or even 60 mol % to 100 mol % of the ethylenically unsaturated monomers are ethylenically unsaturated acids or anhydrides.

[0122] The molar ratio of the total ethylenically unsaturated monomers (ethylenically unsaturated acid or anhydride + other ethylenically unsaturated monomers, if any) to the mercapto-functionalized polyether polyol in step ii) may be 4: 1 to 50: 1. In a specific embodiment, the molar ratio of the total ethylenically unsaturated monomers to the mercapto-functionalized polyether polyol in step ii) is 4: 1 to 30: 1, or even 5: 1 to 20: 1.

[0123] Step ii) may optionally be carried out in the presence of a diluent. In a particular embodiment, step ii) is carried out without adding a diluent.

[0124] Suitable diluents include monoalcohols (ie monohydric alcohols), polyols, hydrocarbons, ethers and mixtures thereof. Preferably, the diluent in step ii) is a polyol.

[0125] Suitable polyols for use as diluents in step ii) include polyols having a hydroxyl functionality of 2 to 8; or even 2 to 6. In a particular embodiment, the molecular weight of the polyol is from 300 Da to 15,000 Da, or from 1,000 Da to 12,000 Da. In one embodiment, its molecular weight is from 2,000 Da to 6,000 Da. In another embodiment, the hydroxyl number of the polyol is in the range of 10 mg KOH / g to 400 mg KOH / g, or from 15 mg KOH / g to 150 mg KOH / g, or even from 15 mg KOH / g to 100 mg KOH / g.

[0126] In one embodiment, the polyol used as diluent in step ii) is a polyol having a hydroxyl functionality of 2 to 6, a molecular weight of 300 Da to 15,000 Da and a hydroxyl number of 15 mg KOH / g to 150 mg KOH / g.

[0127] In one embodiment, the polyol is selected from polyether polyols, polyester polyols and polycarbonate polyols, ie polyols as defined above having ether groups, ester groups or carbonate groups, respectively, within the polymer chain.

[0128] In a preferred embodiment, the polyol is a polyether polyol, also commonly referred to as a polyalkylene polyether polyol. In a preferred embodiment, the polyether polyol is the product of polymerizing an alkylene oxide having 2 to 4 carbon atoms (e.g., ethylene oxide, propylene oxide, butylene oxide, and mixtures thereof) in the presence of a starting compound having at least one active hydrogen atom, preferably 2 to 6 active hydrogen atoms.

[0129] Suitable starting compounds for obtaining the polyether polyols which can be used as the diluent in step ii) include, for example, polyhydroxy compounds such as ethylene glycol, propylene glycol, diethylene glycol, dipropylene glycol, tripropylene glycol, 1,3-dihydroxypropane, 1,3-dihydroxybutane, 1,4-dihydroxybutane, 1,4-dihydroxyhexane, 1,5-dihydroxyhexane, 1,6-dihydroxyhexane, 1,2-dihydroxyoctane, 1,3-dihydroxyoctane, 1,4-dihydroxyoctane, 1,6 -dihydroxyoctane, 1,8-dihydroxyoctane, 1,10-dihydroxydecane, 1,2,4-trihydroxybutane, 1,2,6-trihydroxyhexane, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane, glycerol, sorbitol, pentaerythritol, xylitol, arabitol, mannitol, glucose, sucrose, etc.; water; ammonia; amino alcohols, such as ethanolamine, diethanolamine, triethanolamine; and primary and / or secondary amines or polyamines, such as ethylenediamine, aniline and toluenediamine. Suitable polyether polyols can be formed by alkoxylation of the starter. The alkoxylation reaction can be catalyzed using any conventional catalyst, including, for example, potassium hydroxide or a double metal cyanide (DMC) catalyst.

[0130] In one embodiment, the polyether polyol that can be used as diluent in step ii) consists of propylene oxide units, ethylene oxide units or a mixture thereof. That is, it is poly(ethylene oxide and / or propylene oxide).

[0131] In another embodiment, the polyether polyol that can be used as the diluent in step ii) consists of propylene oxide units and ethylene oxide units; that is, it is a propylene oxide-ethylene oxide copolymer. In one embodiment, the polyether polyol is a random or block propylene oxide-ethylene oxide copolymer with or without ethylene oxide terminal (end) groups.

[0132] Thus, the polyether polyol which can be used as diluent in step ii) can be a propylene oxide homopolymer or an ethylene oxide homopolymer, or a random or block propylene oxide-ethylene oxide copolymer with or without ethylene oxide terminal groups.

[0133] In one embodiment, the polyether polyol that can be used as the diluent in step ii) consists of propylene oxide monomers and 0 to 95 wt. %, or even 0 to 75 wt. %, of ethylene oxide monomers, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether polyol consists of propylene oxide and 0 to 50 wt. %, or even 0 to 30 wt. %, of ethylene oxide, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether is a propylene oxide homopolymer.

[0134] In one embodiment, the polyether polyol that can be used as the diluent in step ii) consists of ethylene oxide monomers and 0 to 95 wt. %, or even 0 to 75 wt. %, of propylene oxide monomers, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In another embodiment, the polyether polyol consists of ethylene oxide and 0 to 50 wt. %, or even 0 to 30 wt. % of propylene oxide, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether polyol is an ethylene oxide homopolymer.

[0135] In another embodiment, the polyether polyol that can be used as the diluent in step ii) consists of propylene oxide and ethylene oxide, and contains 2% to 98% by weight of propylene oxide monomers and 2% to 98% by weight of ethylene oxide monomers, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers). In one embodiment, the polyether polyol that can be used as the diluent in step ii) consists of propylene oxide and ethylene oxide, and contains 2% to 50% by weight, or even 5% to 30% by weight of ethylene oxide, based on the weight of the monomers (propylene oxide monomers + ethylene oxide monomers).

[0136] The hydroxyl functionality of the polyether polyol used as diluent in step ii) may be 2, 3, 4, 5, 6, 7 or 8. In one embodiment, its functionality is from 3 to 6. In a particular embodiment, its functionality is from 2 to 5, or even from 2 to 4. In another embodiment, its functionality is 3.

[0137] In a particular embodiment, the polyether polyol that can be used as the diluent in step ii) is a poly(ethylene oxide and / or propylene oxide) having a hydroxyl functionality of 2 to 6 and a molecular weight of 300 Da to 15,000 Da.

[0138] The polyether polyol that can be used as the diluent in step ii) can be the same as or different from the polyether polyol used to prepare the mercapto-functionalized polyether polyol in step i).

[0139] If a polyol is used as diluent in step ii), said step is carried out in a mixture of polyols (the polyol and the thiol-functionalized polyether polyol). Preferably, the polyol that can be used as diluent in step ii) has not been subjected to any reaction or treatment that causes thiol functionalization. In this case, the mixture of polyols in step ii) will have a thiol amount level that is lower than the thiol amount level of the thiol-functionalized polyether polyol obtained in step i).

[0140] In a particular embodiment, step ii) is optionally carried out in the presence of a polyol as a diluent, and the mixture of polyols in step ii) (polyol (if any) + thiol-functionalized polyether polyol) has on average an amount of thiol groups of less than 4 moles, or even less than 3 moles, per mole of total polyols (i.e. the mixture of polyols present in step ii)), provided that said value is equal to or less than x, where x is the hydroxyl functionality of the starting polyether polyol minus 1. In a particular embodiment, the mixture of polyols in step ii) has on average an amount of thiol groups of from 0.05 moles to 4.0 moles, or even from 0.05 moles to 3.0 moles, per mole of total polyols present in step ii), provided that said value is equal to or less than x, where x is the hydroxyl functionality of the starting polyether polyol minus 1. In one embodiment, it comprises on average from 0.1 to 3.0 mol, or even from 0.5 to 3.0 mol, of mercapto groups per mole of polyol present in step ii), provided that said value is equal to or less than x, wherein x is the hydroxyl functionality of the starting polyether polyol minus 1.

[0141] In a particular embodiment, the thiol-functionalized polyether polyol reacted in step ii) comprises from 0.05 mol to 4.0 mol, or even from 0.05 mol to 3.0 mol of thiol groups per mole of total polyols present in step ii) (i.e. thiol-functionalized polyether polyols present in step ii) + other polyols, if any, such as optional diluents), with the proviso that said value is equal to or less than x, where x is the hydroxyl functionality of the starting polyether polyol minus 1. In another embodiment, it comprises from 0.1 mol to 3.0 mol, or even from 0.5 mol to 3.0 mol of thiol groups per mole of total polyols present in step ii). In another embodiment, it comprises from 0.8 mol to 3.0 mol of thiol groups per mole of total polyols present in step ii), with the proviso that said value is equal to or less than x, where x is the hydroxyl functionality of the starting polyether polyol minus 1.

[0142] According to one embodiment, the diluent may be present in step ii) in an amount of 0% to 400% by weight relative to the weight of the thiol-functionalized polyether polyol. In one embodiment, it is present in an amount of 5% to 400% by weight relative to the weight of the thiol-functionalized polyether polyol. In another embodiment, the diluent may be present in step ii) in an amount of 0% to 300% by weight, or even in an amount of 0% to 250% by weight relative to the weight of the thiol-functionalized polyether polyol.

[0143] Step ii) is carried out in the presence of a free radical initiator. The term "free radical initiator" or "free-radical initiator" refers to a compound that generates free radicals when energy (e.g., from light or heat) is imparted to the compound. The free radical initiator can generate thiol radicals by reacting with the thiol-functionalized polyether polyol. The thiol radical can also initiate a reaction with the carbon-carbon double bond in the ethylenically unsaturated acid or anhydride (or other ethylenically bonded monomer, if present), thereby causing the ethylenically unsaturated acid or anhydride (and other ethylenically bonded monomer, if present) to polymerize with itself.

[0144] Suitable free radical initiators for step ii) include conventional free radical initiators known in the art, such as thermal initiators and photoinitiators. Suitable free radical initiators include thermal initiators, such as alkyl and aryl peroxides, alkyl and aryl hydroperoxides, acyl peroxides, peroxyesters, persulfates, perborates, percarbonates and azo compounds. Some specific examples include hydrogen peroxide, dibenzoyl peroxide, didecanoyl peroxide, dilauroyl peroxide, t-butyl hydroperoxide, benzoyl peroxide, di-t-butyl peroxide, di(3,5,5-trimethylhexanoyl) peroxide, diisobutyryl peroxide, diethyl t-butyl peroxyacetate, t-butyl peroctoate, t-butyl peroxyisobutyrate, t-butyl peroxy3,5,5-trimethylhexanoate, t-butyl perbenzoate, t-butyl peroxypivalate, t-butyl peroxy-2-ethylhexanoate, t-amyl peroxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutyl peroxy-2-ethylhexanoate, cumene hydroperoxide, azobis(isobutyronitrile), and 2,2′-azobis-(2-methylbutyronitrile). Suitable photoinitiators include benzoin ethers, benzil, α-hydroxybenzophenone or α-alkoxybenzophenone or α-aminoalkylphenone, acylphenyl oxide, thioxanthones and benzophenones. Some specific examples include benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin n-propyl ether, benzoin isobutyl ether, benzoin n-butyl ether, benzoin, benzil, acetophenone, 2,2-diethoxyacetophenone, 4'-hydroxyacetophenone, p-dimethylaminoacetophenone, benzophenone, 2-chlorobenzophenone, 2-benzyl-2-(dimethylamino)-4'-morpholinobutyrophenone, diphenyl (2,4,6-trimethyl-benzoyl) phosphine oxide, thioxanthen-9-one, 2-chlorothioxanthen-9-one, 4-(dimethylamino)benzophenone and 4,4'-dihydroxybenzophenone.

[0145] In one embodiment, the initiator includes acyl peroxides such as didecanoyl peroxide, lauroyl peroxide, diisobutyryl peroxide, and di(3,5,5-trimethylhexanoyl) peroxide; peroxyesters such as tert-amylperoxy-2-ethylhexanoate, 1,1,3,3-tetramethylbutylperoxy-2-ethylhexanoate; hydroperoxides such as cumene hydroperoxide; and azo compounds such as azobis(isobutyronitrile) and 2,2'-azobis-(2-methylbutyronitrile).

[0146] In one embodiment, the molar ratio of the free radical initiator to the thiol-functionalized polyether polyol in step ii) is from 0.005: 1 to 0.5: 1. In a specific embodiment, the molar ratio of the free radical initiator to the thiol-functionalized polyether polyol in step ii) is from 0.005: 1 to 0.2: 1, or even from 0.005: 1 to 0.1: 1. In one embodiment, the ratio is from 0.01: 1 to 0.2: 1, or even from 0.01: 1 to 0.1: 1.

[0147] In a specific embodiment, the amount of free radical initiator used in step ii) is 0.01 wt % to 3 wt %, or 0.05 wt % to 2 wt %, relative to the weight of the thiol-functionalized polyether polyol. In another embodiment, the amount of free radical initiator in step ii) is 0.01 wt % to 0.3 wt %, or 0.03 wt % to 0.25 wt %, relative to the weight of the thiol-functionalized polyether polyol.

[0148] In one embodiment, the thiol-functionalized polyether polyol is present in step ii) in an amount of 20% to 98% by weight, or even 50% to 98% by weight, relative to the total weight of all components in step ii). In a specific embodiment, the thiol-functionalized polyether polyol is present in step ii) in an amount of 80% to 98% by weight, or even 85% to 98% by weight, based on the total weight of all components in step ii).

[0149] In one embodiment, the diluent may be present in step ii) in an amount of 0% to 80% by weight, or even 0% to 50% by weight, relative to the total weight of all components in step ii). In a specific embodiment, the diluent may be present in step ii) in an amount of 0% to 20% by weight, or even 0% to 10% by weight, based on the total weight of all components in step ii).

[0150] In one embodiment, the ethylenically unsaturated acid or anhydride is present in step ii) in an amount of 2 to 30 wt %, or even 2 to 20 wt %, relative to the total weight of all components in step ii). In a specific embodiment, the ethylenically unsaturated acid or anhydride is present in step ii) in an amount of 2 to 15 wt %, or 3 to 20 wt %, based on the total weight of all components in step ii). In another embodiment, it is 3 to 15 wt %.

[0151] In one embodiment, other ethylenically unsaturated monomers other than the ethylenically unsaturated acid or anhydride are present in step ii) in an amount of 0% to 30% by weight, or even 0% to 20% by weight, relative to the total weight of all components in step ii). In a specific embodiment, other ethylenically unsaturated monomers other than the ethylenically unsaturated acid or anhydride are present in step ii) in an amount of 0% to 15% by weight, or even 0% to 10% by weight, based on the total weight of all components in step ii).

[0152] In one embodiment, the total ethylenically unsaturated monomers (ethylenically unsaturated acid or anhydride + other ethylenically unsaturated monomers, if any) are present in step ii) in an amount of 2% to 60% by weight, or even 3% to 60% by weight, relative to the total weight of all components in step ii). In a specific embodiment, the total amount of ethylenically unsaturated monomers in step ii) is 2% to 40% by weight, or even 3% to 25% by weight, based on the total weight of all components in step ii). In another embodiment, it is 3% to 20% by weight, or even 3% to 15% by weight.

[0153] In one embodiment, the free radical initiator is present in step ii) in an amount of 0.01% to 5% by weight, or even 0.03% to 1% by weight, relative to the total weight of all components in step ii). In another embodiment, the free radical initiator is present in step ii) in an amount of 0.01% to 0.2% by weight, relative to the total weight of all components in step ii).

[0154] In one embodiment, step ii) comprises reacting 50 to 98 wt % of a thiol-functionalized polyether polyol, 0 to 50 wt % of a diluent, 2 to 30 wt % of an ethylenically unsaturated acid or anhydride, 0.01 to 5 wt % of a free radical initiator, and 0 to 30 wt % of other ethylenically unsaturated monomers other than the ethylenically unsaturated acid or anhydride, relative to the total weight of all components in step ii).

[0155] According to one embodiment, step ii) comprises reacting 80 to 98 wt % of a thiol-functionalized polyether polyol, 0 to 20 wt % of a diluent, 2 to 30 wt % of an ethylenically unsaturated acid or anhydride, 0.01 to 5 wt % of a free radical initiator, and 0 to 15 wt % of other ethylenically unsaturated monomers other than the ethylenically unsaturated acid or anhydride, relative to the total weight of all components in step ii).

[0156] If a thermal free radical initiator is used, the temperature at which step ii) occurs should be selected to allow thermal decomposition of the free radical initiator, thereby generating free radicals capable of initiating the polymerization reaction. In a particular embodiment, step ii) is carried out at a temperature of 25°C to 200°C, such as 60°C to 160°C, or even 60°C to 150°C.

[0157] The reaction in step ii) can be carried out for 0.5 hours to 24 hours, or even for 2 hours to 24 hours. In a particular embodiment, step ii) is carried out for 2 hours to 15 hours, or even for 4 hours to 10 hours.

[0158] Step ii) (polymerization) can be carried out in several ways including batch process, semi-batch process and continuous process.

[0159] After step ii), the polymer of the invention is obtained.

[0160] According to some specific embodiments, the molecular weight of the polymer of the invention is between 600 Da and 18,000 Da. In one embodiment, its molecular weight is between 3,200 Da and 18,000 Da, or even between 4,500 Da and 16,000 Da.

[0161] In some specific embodiments, the acid value of the polymer of the present invention is in the range of 20 mgKOH / g to 150 mgKOH / g. In one embodiment, the acid value is 20 mgKOH / g to 100 mgKOH / g, or even 25 mgKOH / g to 80 mgKOH / g.

[0162] According to some specific embodiments, the polymer of the present invention has a viscosity of 5,00 mPa s to 250,000 mPa s. In other embodiments, its viscosity is 5,000 mPa s to 210,000 mPa s, or even 10,000 mPa s to 150,000 mPa s.

[0163] The polymers of the invention have been found to be useful as dispersants for polyols obtained by acidolysis of polyurethanes. The term "acidolysis" refers to the treatment of polyurethanes, preferably (waste) polyurethane foams, with carboxylic acids or carboxylic acid derivatives, such as anhydrides, to convert the polyurethanes into (recovered) polyols by chemical degradation.

[0164] The terms "dispersant" and "stabilizer" are used interchangeably herein. These terms generally refer to agents added to a medium to prevent agglomeration or settling of particles contained therein and / or to provide a uniform dispersion.

[0165] Therefore, in a further aspect, the invention relates to the use of a polymer according to the invention as a dispersant in the acid hydrolysis of polyurethanes.

[0166] In a further aspect, the invention relates to the use of the polymers of the invention for preparing polyol dispersions by acidolysis of polyurethanes.

[0167] In another aspect, the invention relates to a process for producing polyol dispersions from polyurethanes, wherein the process comprises reacting polyurethanes with dicarboxylic acids or anhydrides in the presence of a polymer according to the invention at a temperature of 150° C. to 250° C. (acidolysis process).

[0168] In one embodiment, the polyurethane in the acid hydrolysis of the present invention is a polyurethane foam.

[0169] Preferably, the polyurethane or polyurethane material used as a raw material in the acid hydrolysis is polyurethane waste, including flexible, semi-rigid and rigid (eg PUR foam and PIR foam) polyurethane waste, such as flexible, semi-rigid and rigid polyurethane waste foam.

[0170] The non-limiting exemplary definition of the term polyurethane refers to a polymer comprising carbamate groups produced by the reaction of polyols and isocyanates. In one embodiment, these polymers can be obtained by a preparation having an isocyanate index of 70 to 550. In the context of the present invention, the term polyurethane is also intended to include polyisocyanurates (PIR). The term polyisocyanurate is intended to represent a polymer produced by the reaction of polyols and isocyanates, which polymers, in addition to containing carbamate functional groups, also contain other types of functional groups, particularly triisocyanate rings formed by the trimerization of isocyanates. Polyisocyanurates are generally obtained by preparations showing an isocyanate index of 180 to 550. In one embodiment, the polyurethane used in the present invention is a polymer obtained by a preparation having an isocyanate index of 70 to 140 or 80 to 120. In another embodiment, it is a polymer obtained by a preparation having an isocyanate index of 90 to 110. The isocyanate index is defined as the ratio of the isocyanate groups present in the polyurethane preparation relative to the reactive hydrogen atoms of isocyanates. The isocyanate index therefore expresses the percentage of isocyanate actually used in a formulation relative to the amount of isocyanate theoretically required to react with the amount of isocyanate-reactive hydrogen used in the formulation.

[0171] Flexible polyurethane foam is a polyurethane having an open-cell structure and a hardness at 40% load of 30 N to 900 N, measured according to EN ISO 2439:2008 (E).

[0172] Semi-rigid polyurethane foams are polyurethanes which have an open-cell structure but have a compressive strength measured according to EN ISO 844:2009 of at least 100 kPa.

[0173] Rigid polyurethane foams are polyurethanes which have a closed-cell structure in the polyurethane region and a compressive strength of at least 100 kPa, measured to EN ISO 844:2009. In the context of the present invention, the term rigid polyurethane foam shall also encompass rigid polyisocyanurate foams.

[0174] For the purposes of the present invention, polyurethane waste includes waste from post-consumer use, particularly contemplated polyurethane materials disposed of by end consumers. These materials preferably include polyurethane foams, high resilience polyurethane foams, polyurethane viscoelastic foams and / or other polyurethane foams. Preferred polyurethane waste is waste from cushions, interior trims and mattresses.

[0175] Optionally, the polyurethane waste can be polyurethane mixed with other polymers and / or fillers (e.g. those based on polyethers or polyesters and polyureas), and its copolymers are suitable for the acidolysis process according to the present invention. The present invention is also applicable to polyurethanes associated with thermoplastic polymers such as polyolefins, ABS or PVC. Such thermoplastics can be filtered out from the recovered polyol after the acidolysis reaction.

[0176] However, it is preferred to use polyurethane waste that is free of textiles, metal, wood and other foreign matter. It is also preferred that the polyurethane waste is in comminuted form.

[0177] In a particular embodiment, the polyurethane waste is sorted to separate the polyurethane from other foreign materials (eg, other polymers other than polyurethane) and / or shredded prior to acid hydrolysis.

[0178] Suitable dicarboxylic acids or anhydrides for the acidolysis include succinic acid, glutaric acid, maleic acid, malic acid, phthalic acid, adipic acid, succinic anhydride, glutaric anhydride, maleic anhydride, malic anhydride, phthalic anhydride, adipic anhydride, and mixtures thereof.

[0179] Based on the total mass of all starting materials or components in the acidolysis (i.e., the total mass of the acidolysis reaction), the dicarboxylic acid or anhydride can be used in a total amount of 3 wt % to 50 wt %, or even 5 wt % to 40 wt %. The starting materials or components in the acidolysis of the present invention include the polyurethane, the polymer of the present invention, the dicarboxylic acid or anhydride, and any other optional components present in the reaction mixture.

[0180] In one embodiment, the dicarboxylic acid or anhydride is used in the acidolysis in an amount of 3 to 50 wt %, or even 5 to 40 wt %, based on the sum of the masses of the polyurethane, the polymer of the invention and the dicarboxylic acid or anhydride.

[0181] In one embodiment, the weight ratio of dicarboxylic acid or anhydride to polyurethane in the acid hydrolysis is from 0.05:1 to 1:1, or even from 0.1:1 to 0.5:1.

[0182] Based on the total mass of all starting materials or components in the acidolysis, the polymer of the present invention can be used in an amount of 0.5% to 40% by weight, or even 1.0% to 40% by weight. In a specific embodiment, based on the total mass of the starting materials or components in the acidolysis, the polymer of the present invention can be used in an amount of 1.5% to 40% by weight, or even 1.5% to 20% by weight. In a specific embodiment, based on the total mass of the starting materials or components in the acidolysis, the polymer of the present invention can be used in an amount of 2% to 40% by weight, or 2% to 20% by weight, or even 2% to 10% by weight.

[0183] In one embodiment, the polymer of the present invention is used in the acid hydrolysis in an amount of 0.5% to 40% by weight, or even 1.0% to 40% by weight, based on the sum of the masses of the polyurethane, the polymer of the present invention and the dicarboxylic acid or anhydride. In a specific embodiment, the polymer of the present invention is used in an amount of 1.5% to 40% by weight, or 2% to 40% by weight, or even 2% to 20% by weight, based on the sum of the masses of the polyurethane, the polymer of the present invention and the dicarboxylic acid or anhydride.

[0184] In one embodiment, the weight ratio of the polymer of the invention to the polyurethane in the acid hydrolysis is from 0.02:1 to 0.25:1, or even from 0.2:1 to 0.15:1.

[0185] Based on the total mass of all starting materials or components in the acidolysis, the polyurethane can be used in an amount of 45% to 95% by weight, or even 50% to 90% by weight. Based on the total mass of all starting materials or components in the acidolysis, the polyurethane can be used in an amount of 50% to 85% by weight, or even 50% to 80% by weight.

[0186] In one embodiment, the polyurethane is used in the acidolysis in an amount of 45% to 95% by weight, or even 50% to 90% by weight, based on the sum of the masses of the polyurethane, the polymer of the invention and the dicarboxylic acid or anhydride. In one embodiment, the polyurethane is used in the acidolysis in an amount of 50% to 85% by weight, or even 50% to 80% by weight, based on the sum of the masses of the polyurethane, the polymer of the invention and the dicarboxylic acid or anhydride.

[0187] Optionally, the acidolysis may be carried out in the presence of other additional components such as diluents. Suitable diluents include those mentioned herein in connection with the optional diluent in step ii) of the method for preparing the polymer of the present invention. In a particular embodiment, the diluent is a polyol selected from those disclosed above in connection with the diluent in step ii) of the method for preparing the polymer of the present invention. The optional diluent in the acidolysis may be the same or different from the optional diluent in step ii) of the method for preparing the polymer of the present invention.

[0188] In a particular embodiment, the diluent may be used in the acid hydrolysis in an amount of 0 wt % to 20 wt %, or even 0 wt % to 10 wt %, based on the total mass of all starting materials or components in the acid hydrolysis.

[0189] The polyurethane used in the acidolysis may contain other components commonly present in polyurethanes, such as fillers, surfactants, flame retardants, catalysts, and / or colorants (pigments or dyes), such as calcium carbonate, styrene-acrylonitrile copolymers, triethylenediamine, N,N-dimethylethanolamine, dibutyltin dilaurate, tin octoate, melamine, polysiloxane-polyoxyalkylene block copolymers, ureas and / or imides.

[0190] The acid hydrolysis may be carried out at a temperature ranging from 150° C. to 250° C. According to a particular embodiment, the acid hydrolysis may be carried out at a temperature ranging from 170° C. to 250° C., or even from 170° C. to 220° C.

[0191] The acid hydrolysis may be carried out for 1 hour to 24 hours, or 1 hour to 8 hours, or even 2 hours to 6 hours.

[0192] In some embodiments of the invention, the acid hydrolysis is carried out in a reactor or container made of stainless steel. In other embodiments, all devices and equipment (e.g., containers, agitators, reactors) in contact with the starting materials or reactants of the acid hydrolysis are made of stainless steel.

[0193] The acid hydrolysis according to the present invention can be carried out as a batch process, a semi-batch process or a continuous process.

[0194] After the acid hydrolysis, the polyol dispersion of the invention is obtained.

[0195] According to some specific embodiments, the hydroxyl number of the polyol dispersion of the present invention is in the range of 5 mgKOH / g to 650 mgKOH / g. In a specific embodiment, when the polyurethane used in the acid hydrolysis is a flexible polyurethane foam, the hydroxyl number of the obtained polyol dispersion is in the range of 20 mgKOH / g to 50 mgKOH / g.

[0196] In some specific embodiments, the acid value of the polyol dispersion of the present invention is in the range of 5 mgKOH / g to 20 mgKOH / g. In one embodiment, the acid value is 5 mgKOH / g to 15 mgKOH / g.

[0197] According to some specific embodiments, the viscosity of the polyol dispersion of the present invention is from 5,000 mPa s to 30,000 mPa s. In other embodiments, the viscosity is from 5,000 mPa s to 25,000 mPa s.

[0198] According to some specific embodiments, the particle size D50 of the polyol dispersion of the present invention is equal to or less than 50 μm. In one embodiment, the particle size D50 of the polyol dispersion of the present invention is equal to or less than 20 μm, or even equal to or less than 10 μm. In other embodiments, its particle size D50 is from 0.5 μm to 20 μm, or even from 0.5 μm to 10 μm. In one embodiment, its particle size D50 is from 0.8 μm to 10 μm.

[0199] The polyol dispersion of the present invention can be used directly to make polyurethane, or it can be reacted or mixed with other components to adjust its properties (eg, hydroxyl number, acid value and / or viscosity) before it is used to make polyurethane.

[0200] For example, before being used to make polyurethanes, they can be reacted with diols or triols to increase their OH number and / or reduce their acid number as disclosed in WO 2018 / 091568 A1.

[0201] Alternatively or additionally, before use in the manufacture of the polyurethane it may be mixed with a polyether polyol (different from the polyol dispersion of the invention), for example to reduce its viscosity. Suitable polyether polyols include those disclosed above in connection with the preparation of the polymers of the invention.

[0202] The polyol dispersion obtained after the acidolysis is an isocyanate-reactive polyol dispersion and can therefore be used for the production of polyurethanes.

[0203] Therefore, in a further aspect, the present invention relates to the use of the polyol dispersion according to the invention for producing polyurethanes.

[0204] In another aspect, the present invention relates to a process for preparing a polyurethane comprising reacting the polyol dispersion of the present invention with a polyisocyanate. In another aspect, the present invention relates to a polyurethane obtainable by said process (herein denoted final polyurethane).

[0205] According to one embodiment, the final polyurethane is a polyurethane foam, including flexible polyurethane foam, semi-rigid polyurethane foam and rigid polyurethane foam.

[0206] Conventional additives, their amounts and reaction conditions used to prepare polyurethanes will vary depending on the type of polyurethane to be prepared and the desired properties. The skilled artisan is aware of the different reagents, additives and conditions required to prepare polyurethanes.

[0207] The method for preparing polyurethane comprises reacting the polyol dispersion of the present invention with a polyisocyanate, optionally in the presence of additional additives for preparing polyurethane (e.g., additional polyols, chain transfer agents, catalysts, stabilizers, blowing agents, flame retardants, fillers and / or pigments). Suitable methods for preparing polyurethane are well known in the art.

[0208] Suitable polyisocyanates include aromatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates and combinations thereof. Representative of these types are diisocyanates such as m-phenylene diisocyanate, toluene-2,4-diisocyanate and toluene-2,6-diisocyanate, a mixture of 2,4-hexamethylene-1,6-diisocyanate and 2,6-hexamethylene-1,6-diisocyanate, tetramethylene-1,4-diisocyanate, cyclohexane-1,4-diisocyanate, hexahydrotoluene diisocyanate (and isomers), naphthylene-1,5-diisocyanate, 1-methoxy-phenyl-2,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, diphenylmethane-2,4'-diisocyanate. esters and diphenylmethane-2,2'-diisocyanate, 4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenyl diisocyanate, 3,3'-dimethyl-4,4'-biphenyl diisocyanate and 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate; triisocyanates such as 4,4',4'-triphenylmethane triisocyanate, polymethylene polyphenyl isocyanate and toluene 2,4,6-triisocyanate; and tetraisocyanates such as 4,4'-dimethyldiphenylmethane-2,2',5,5'-tetraisocyanate and mixtures thereof. Particularly useful are the 4,4'-, 2,4'- and 2,2'-isomers of diphenylmethane diisocyanate (MDI), toluene-2,4- and toluene-2,6-diisocyanate (TDI), and mixtures thereof.

[0209] In one embodiment, the polyisocyanate is used to prepare the polyurethane at an isocyanate index of 60 to 140, or 80 to 120, or even 90 to 110.

[0210] Suitable blowing agents are known in the art, such as carbon dioxide produced by decarboxylation of carbamic acid produced by reaction of water with isocyanate, liquid carbon dioxide, methylene chloride, HCFCs or pentane.

[0211] Suitable catalysts include amino-containing compounds such as triethylenediamine, N-methylmorpholine, N,N-dimethylcyclohexylamine, pentamethyldiethylenetriamine, tetramethylethylenediamine, bis(dimethylaminoethyl)ether, 1-methyl-4-dimethylaminoethyl-piperazine, 3-methoxy-N-dimethylpropylamine, N-ethylmorpholine, dimethylethanolamine, 4-cocomorpholine derivatives (N-cocomorpholine), N,N-dimethyl-N',N'-dimethylisopropylpropylenediamine, N,N-diethyl-3-diethylaminopropylamine and dimethylbenzylamine; and metal catalysts based on tin, zinc or bismuth such as tin octoate, dibutyltin dilaurate or zinc octoate.

[0212] Additional additives that can be used to prepare the polyurethane include fillers (e.g., talc, silica, titanium dioxide, magnesium oxide, calcium carbonate, carbon black, graphite, magnesium silicate or clays such as kaolinite and montmorillonite); flame retardants (e.g., halogenated flame retardants such as hexabromocyclododecane and brominated polymers, or phosphorus flame retardants such as triphenyl phosphate, dimethyl methylphosphonate, red phosphorus or aluminum diethylphosphinate); acid scavengers (e.g., calcium stearate, magnesium oxide, zinc oxide, tetrasodium pyrophosphate or hydrotalcite); antioxidants (e.g., sterically hindered phenols, phosphites and mixtures thereof); surfactants (e.g., silicon surfactants) and pigments.

[0213] Unless otherwise indicated, the term "molecular weight" as used herein refers to the number average molecular weight. The number average molecular weight is determined by gel permeation chromatography. Preferably, the molecular weight means the number average molecular weight as measured by gel permeation chromatography using polyethylene glycol as a standard.

[0214] The viscosities disclosed therein are determined at 25° C. The viscosity is determined at 25° C. and 25 sec −1 according to EN ISO 3219. Viscosity measurements (in mPa·s) can be obtained with a Haake iQ Viscometer rheometer using a spindle CC25DIN / Ti.

[0215] The term "hydroxyl functionality" or "functionality" is understood to be the average number of hydroxyl groups per polyol molecule, which is theoretically equal to the number of hydroxyl groups of the initiator molecules used in the polyol synthesis. As used herein, the term "hydroxyl functionality" or "functionality" in relation to a polyol refers to the functionality of the initiator used in its preparation.

[0216] As used herein, hydroxyl number is defined as the number of milligrams of potassium hydroxide required to completely hydrolyze a fully phthalated derivative prepared from 1 gram of polyol. Hydroxyl number can be determined according to ASTM-E1899.

[0217] The hydroxyl number can also be defined by the following equation:

[0218] OH = (56.1 × 1000 × f) / mol.wt.

[0219] in:

[0220] OH: represents the number of hydroxyl groups of the polyol.

[0221] f: represents the functionality of the polyol, and

[0222] mol.wt. represents the molecular weight of the polyol.

[0223] The acid value is defined as the milligrams of potassium hydroxide required to completely neutralize the sample and can be determined according to ASTM D 1662. It can be measured by titrating the polyol with KOH in a mixture of isopropanol and water (62.5 / 37.5 w / w).

[0224] The particle size D50 (or Dx(50)) means the median diameter (the particle size at which 50% of the volume of the particles lies within the specified value of D50). It can be determined by laser diffraction, for example using a Mastersizer 3000 spectrometer by dispersing the sample in ethanol and calculating the particle size distribution using the Fraunhofer theory.

[0225] The present invention is illustrated by the following examples, which are not intended to limit the scope of the present invention in any way.

[0226] Example

[0227] method

[0228] The hydroxyl number, acid value, molecular weight, viscosity and particle size D50 values ​​disclosed in the following examples are determined according to the standards or methods mentioned above.

[0229] Material

[0230] Polyol A: a sorbitol (functionality 6) initiated polyether polyol (PO / EO) having a molecular weight of 11,410 Da, a hydroxyl number of 29.5 mg KOH / g, a polyethylene oxide end block content of 16.2 wt % (based on the total weight of ethylene oxide monomer and propylene oxide monomer (i.e., OE / (OE+OP) without taking into account the weight of the starter)), and a viscosity at 25° C. of 1500 mPa s.

[0231] Polyol B: a glycerol (functionality 3) initiated polyether polyol (PO / EO) having a molecular weight of 4,800 Da, a hydroxyl number of 35 mg KOH / g and a content of 18 wt% polyethylene oxide end blocks (based on the total weight of ethylene oxide monomer and propylene oxide monomer) and a viscosity at 25°C of 870 mPa s.

[0232] Sulfuric acid (98%) was purchased from Sigma Aldrich.

[0233] Thioglycolic acid (98%) was purchased from Sigma Aldrich.

[0234] Acrylic acid (98%) was purchased from Acros Organics.

[0235] Cumyl hydroperoxide (80%) (CHP) was purchased from Acros Organics.

[0236] Trigonox 421 was purchased from Nuryon.

[0237] F4811 is a polyol from Repsol. It is glycerol propoxylated with 12% ethylene oxide; has a molecular weight of 3500 and a hydroxyl number of 48 mgKOH / g.

[0238] BDE and 33 is an amine catalyst available from Evonik.

[0239] 29 is a tin octoate based metal catalyst available from Evonik.

[0240] B 8255 is a silicone based surfactant available from Evonik.

[0241] TDI T80 / 20 is a mixture of two isomeric forms of 2,4-toluene diisocyanate and 2,6-toluene diisocyanate in a ratio of 80:20 and is available from Covestro

[0242] Examples 1 to 3: General Procedure for Synthesis of Thiol-Functionalized Polyether Polyols

[0243] The polyol, the compound of formula (I) and concentrated sulfuric acid were loaded into a 1 L glass reactor equipped with a stirrer, a jacket, and connected to a vacuum pump. The temperature was raised to 120° C. and maintained at this temperature for 7 hours. A vacuum (150 mbar) was applied during the entire process to remove water from the system.

[0244] Details of the examples and the properties of the products obtained are shown in the table below.

[0245]

[0246]

[0247] Examples 4 to 8: General process of polymerization (grafting) reaction

[0248] A 250 mL glass reactor equipped with mechanical stirring, a heating jacket and a condenser was charged with a mercapto-functionalized polyol and acrylic acid. Nitrogen was bubbled into the mixture for 5 minutes to remove oxygen, and then a free radical initiator was added to the system. The temperature was raised to 90° C. under nitrogen and maintained for 8 hours.

[0249] Details of the examples and the properties of the products obtained are shown in the table below.

[0250]

[0251] Examples 9 to 16: General Process of Acid Hydrolysis of Polyurethane Foam

[0252] The polyurethane foam acid hydrolysis is carried out according to the process described in DE 19512778 C1. Basically, an electrically heated temperature-controlled three-necked glass reactor equipped with a stirrer is used for the process. The dispersant is first introduced into the reactor. The temperature is then raised to 200° C., and water-foamed toluene diisocyanate (TDI) flexible polyurethane foam waste and dicarboxylic acid are added to the dispersant. The mixture is stirred at 200° C. for 2 to 6 hours and then cooled while stirring.

[0253] Details of the examples and the properties of the resulting products are shown in the table below. The indicated weight % are based on the total mass of the components added to the reactor.

[0254]

[0255] All of the resulting recycled polyols had finely dispersed particles and were stable against settling for at least one month at room temperature. No gels were found in the recycled polyols.

[0256] Comparative Example 1 (Using Non-Grafted Mercapto-Functionalized Polyol as Dispersant)

[0257] Acid hydrolysis of polyurethane foam was carried out in the same manner as in Examples 9 to 16 above, using 8.62 wt % of the mercapto-functionalized polyol prepared in Example 1 as a dispersant.

[0258] The recycled polyol thus obtained had a very high viscosity which could not even be measured. The particle size Dx(50) was 386 μm and the solid particles precipitated in less than 24 hours.

[0259] Comparative Examples 2 to 5 (Using Grafted Non-Functionalized Polyols as Dispersants)

[0260] In comparative examples 2 to 5, polyols according to DE 19512778 C1 and WO 2018 / 091568 A1 were used as dispersants in the acid hydrolysis of polyurethane foams, i.e. polyether polyols which react directly with ethylenically unsaturated monomers in the presence of free radical initiators without previously functionalizing the polyether polyols with mercapto groups.

[0261] These dispersants obtained by directly grafting acrylic acid onto polyether polyol (polyol B) were used for acidolysis reaction under the same conditions as in the above Examples 9 to 16 according to the present invention.

[0262] Details of each example are shown in the table below. The indicated weight % is based on the total mass of the components added to the reactor.

[0263]

[0264] In Comparative Examples 2 and 4, the dispersant was used in an amount similar to that disclosed for the same type of dispersant in DE 19512778 C1 and WO 2018 / 091568A1, i.e., about 30% by weight. In Comparative Examples 3 and 5, the dispersant was used in an amount similar to that used in the above examples according to the invention.

[0265] The properties of the resulting recycled polyols are as follows:

[0266] - Comparative Example 2: The viscosity of the recycled polyol is very high and cannot even be measured, which makes it unsuitable for its direct use in the manufacture of polyurethane. In addition, the recycled polyol also contains gel, which makes it unsuitable for the manufacture of polyurethane.

[0267] - Comparative Example 3: The recycled polyol contained gel, which made it unsuitable for the manufacture of polyurethane.

[0268] - Comparative Example 4: The recycled polyol has a very high viscosity (81430 mPa·s), which makes it unsuitable for its direct use in the manufacture of polyurethane.

[0269] - Comparative Example 5: The recovered polyol had a large particle size D50 (23.9 μm), which indicated that the polyol dispersion was unstable. In fact, the solid particles precipitated in less than 5 days.

[0270] This comparative example demonstrates that non-mercapto-functionalized grafted polyols, such as those disclosed in DE 19512778 C1 and WO 2018 / 091568 A1, are not as effective as dispersants in the acid hydrolysis of polyurethanes and cannot be used in amounts as low as those according to the invention. In addition, when used in larger amounts, they provide polyol dispersions with very high viscosities, which may prevent their (direct) use in the industrial production of polyurethanes.

[0271] Examples 17 to 20 and Comparative Examples 6 to 9: General Procedure for Preparing Polyurethane Foams

[0272] Recycled polyols of the present invention (Example 9, Example 11, Example 12 and Example 15) and recycled polyols of the present invention (Comparative Examples 2 to 5) were used as starting materials for the preparation of polyurethane foams. The reagents used to prepare the foams and their amounts expressed in parts per hundred parts of polyol (pphp) are detailed in the table below.

[0273] Polyurethane foam was prepared according to the following process. Polyol, water, amine catalyst ( BDE and 33) Tin octanoate catalyst and silicone surfactants The contents were mixed with a stirrer at 2,000 rpm for 60 seconds. The mixture thus obtained was then degassed for 10 seconds. While the mixer was still rotating, the required amount of toluene diisocyanate was added to the container and the contents were mixed at 2,000 rpm for 10 seconds. The mixture was then poured into a 25 cm x 25 cm square test box, where the foam rose until the reaction was complete. The foam was then heated in an oven at 150°C for 30 minutes.

[0274] Subsequently, the foams were allowed to cure at room temperature for 24 hours before evaluation thereof.

[0275]

[0276]

[0277]

[0278] 1) A 10% density value tolerance is acceptable.

[0279] 2) Compressive stress is a measure of the load-bearing properties of a foam and defines the applications in which the foam can be used. In seating or bedding applications, the first determining parameter for optimal comfort is the foam hardness. If the foam is too hard (i.e., higher compressive stress), it may restrict the flow of capillaries under the skin and cause discomfort. 3) Highly resilient foams (ie, higher resilience values) are targeted at high-quality furniture and bedding applications that require improved durability and comfort properties.

[0280] 4) Higher compression set values ​​compared to the target indicate that the recovery rate of the foam used is worse. 5) Higher porosity values ​​mean better air permeability, which is more desirable in flexible polyurethane foams.

[0281] As shown in the table above, by replacing 6 parts of the polyols from Comparative Examples 2 to 5 The flexible polyurethane foam obtained by using F4811 (see the polyurethane foams in Comparative Examples 6 to 9) has a higher The polyurethane foams obtained with F4811 (see Examples 17 to 20) have poorer porosity, compression set 75% values, rebound resilience and compressive stress values. The recycled polyols of the present invention provide polyols with very good properties (compared to those obtained with only F4811 as a polyol source (equivalent to the target value) of polyurethane foam.

Claims

1. Use of a polymer obtainable by a process comprising the following as a dispersant in the acid hydrolysis of polyurethane: i) reacting a polyether polyol having a hydroxyl functionality of 2 to 6 and a number average molecular weight of 300 Da to 15,000 Da with a compound of formula (I) at a molar ratio of compound of formula (I) to polyether polyol of 0.05:1 to x:1 to provide a mercapto-functionalized polyether polyol, wherein x is the hydroxyl functionality of the polyether polyol minus 1, in R 1 selected from H and linear or branched C1 to C 10 Alkyl, and R 2 It is a linear or branched C1 to C 10 Alkylene; and ii) reacting the resulting mercapto-functionalized polyether polyol with an ethylenically unsaturated acid or anhydride monomer in the presence of a free radical initiator.

2. The use according to claim 1, wherein the polyether polyol is composed of propylene oxide units, ethylene oxide units, or a mixture thereof.

3. The method according to claim 1, wherein the polyether polyol has a hydroxyl functionality of 3 to 6, preferably 3 or 6.

4. The use according to any one of claims 1 to 3, wherein the number average molecular weight of the polyether polyol is 3,000 Da to 15,000 Da, preferably 4,000 Da to 13,000 Da.

5. The use according to any one of claims 1 to 4, wherein the molar ratio of the compound of formula (I) to the polyether polyol is 0.1:1 to x:1, preferably 0.5:1 to x:1, wherein x is the hydroxyl functionality of the polyether polyol minus 1.

6. The use according to any one of claims 1 to 5, wherein the molar ratio of the ethylenically unsaturated acid or anhydride monomer to the mercapto-functionalized polyether polyol in step ii) is 3:1 to 30:1, preferably 4:1 to 20:

1.

7. The method according to any one of claims 1 to 6, wherein the ethylenically unsaturated acid or anhydride monomer is selected from acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, angelic acid, tiglic acid, citraconic acid, 2,3-dimethylmaleic acid, 3-butenoic acid, itaconic acid, maleic anhydride, citraconic anhydride, 2,3-dimethylmaleic anhydride and mixtures thereof, preferably acrylic acid.

8. A process for producing a polyol dispersion from a polyurethane, wherein the process comprises reacting the polyurethane with a dicarboxylic acid or anhydride in the presence of a polymer as defined in any one of claims 1 to 7 at a temperature of from 150°C to 250°C.

9. The method according to claim 8, wherein the polymer is present in an amount of 1.5 to 40 wt%; preferably 1.5 to 20 wt% based on the total mass of the reaction.

10. The method according to any one of claims 8 to 9, wherein the weight ratio of dicarboxylic acid or anhydride to polyurethane is from 0.05:1 to 1:1; preferably from 0.1:1 to 0.5:

1.

11. The process according to any one of claims 8 to 10, wherein the dicarboxylic acid or anhydride is selected from succinic acid, glutaric acid, maleic acid, malic acid, phthalic acid, adipic acid, succinic anhydride, glutaric anhydride, maleic anhydride, malic anhydride, phthalic anhydride, adipic anhydride and mixtures thereof.

12. A polyol dispersion obtainable by the process according to any one of claims 8 to 11.

13. Use of the polyol dispersion according to claim 12 for producing polyurethanes, preferably polyurethane foams.

14. A polyurethane obtainable by a process comprising reacting a polyol dispersion according to claim 12 with a polyisocyanate.

15. A polymer obtainable by a process comprising: i) reacting a polyether polyol having a hydroxyl functionality of 3 to 6 and a number average molecular weight of 3,000 Da to 15,000 Da with a compound of formula (I) at a molar ratio of compound of formula (I) to polyether polyol of 0.05:1 to x:1 to provide a mercapto-functionalized polyether polyol, wherein x is the hydroxyl functionality of the polyether polyol minus 1, in R 1 Selected from H and linear or branched C1 to C 10 Alkyl, and R 2 It is a linear or branched C1 to C 10 Alkylene; and ii) reacting the resulting mercapto-functionalized polyether polyol with an ethylenically unsaturated acid or anhydride monomer in the presence of a free radical initiator.

16. The polymer of claim 15, wherein the polyether polyol is composed of propylene oxide units, ethylene oxide units, or a mixture thereof.

17. The polymer of any one of claims 15 to 16, wherein the polyether polyol has a number average molecular weight of 4,000 Da to 13,000 Da.

18. The polymer according to any one of claims 15 to 17, wherein the molar ratio of the compound of formula (I) to the polyether polyol is from 0.1:1 to x:1, preferably from 0.5:1 to x:1, wherein x is the hydroxyl functionality of the polyether polyol minus 1.

19. The polymer according to any one of claims 15 to 18, wherein the molar ratio of the ethylenically unsaturated acid or anhydride monomer to the mercapto-functionalized polyether polyol in step ii) is 3:1 to 30:1; preferably 4:1 to 20:

1.

20. The polymer according to any one of claims 15 to 19, wherein the ethylenically unsaturated acid or anhydride monomer is selected from acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, angelic acid, tiglic acid, citraconic acid, 2,3-dimethylmaleic acid, 3-butenoic acid, itaconic acid, maleic anhydride, citraconic anhydride, 2,3-dimethylmaleic anhydride and mixtures thereof; preferably it is acrylic acid.

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