Depolymerization of polyurethanes, polyureas or polyisocyanurates to polyol products

Abstract

Reacting a waste polymeric product comprising a thermoset having urethane bonds, urea bonds, and / or isocyanurate bonds, a polycarboxylic acid or an anhydride thereof, a first polyether polyol having an average of from 1.8 to 7 hydroxyl groups per molecule and having a number average molecular weight of greater than 350 grams / mole, a second polyether polyol having a number average molecular weight of no greater than 350 grams / mole wherein at least 50 percent of the hydroxyl groups in the second polyether polyol are secondary alcohol can form a reaction product composition directly useful in forming new polyurethane materials.

Description

86171-WO-PCT (DC200017PCT)DEPOLYMERIZATION OF POLYURETHANES, POLYUREAS OR POL YISOCYANUR ATES TO POLYOL PRODUCTSFIELD OF THE INVENTION

[0001] This invention relates to a method of recycling polyurethanes, polyureas or polyisocyanurates, particularly polyurethane foams.BACKGROUND OF THE INVENTION

[0002] Recycling of polymeric materials can be an important approach to reducing polymer (e.g., plastic) waste and also reducing raw material supply demand.

[0003] Recycling of thermosetting material, such as polymers that have both urethane, urea, and / or isocyanurate linkages typically involves chemolysis (i.e., chemical decomposition to simpler and / or smaller compounds). These polymers may be, for example, polyurethanes, polyureas, polyisocyanurates, polyurethane / ureas (having both urethane and urea linkages), polyurethane / isocyanurates (having both urethane and isocyanurates linkages), polyurethane / urea / isocyanurates (having urethane, urea and isocyanurates linkages), and polyurea / isocyanurates (having urea and isocyanurate linkages).

[0004] Past approaches to chemolysis of polyurethanes and polyureas typically involve forming a liquid, dispersion, or paste- like reaction mixture including reagents and fragments of polyurethane products to be recycled. The reagent(s) react with the polyurethane to break down the polyurethane. The reaction product mixture tends to be multi-phase and / or unstable over time (i.e., lack shelf stability). The reaction product can further include primary amine by-products that can interfere with desired reactions when the reaction product is used in forming new polyurethane products. Accordingly, these processes typically include separation and / or purification steps to isolate the desired reaction products before the reaction products can then be used in subsequent chemical processes.

[0005] Certain chemolysis reactions may produce reaction products that have high hydroxyl number (or OH number) and / or primary amine byproducts from the waste polymer having urethane, urea, and / or isocyanurate linkages, making them less ideal or unsuitable for many end use applications. Products from a recycling process having moderate OH number are highly desirable for manufacturing of subsequent polyurethane products such as rigid polyurethane foams.

[0006] It would be desirable to have an efficient, simple, and / or rapid means of converting waste thermosetting polymeric materials having urethane, urea, and / or isocyanurate linkages by chemolysis to form a reaction product composition which can be86171-WO-PCT (DC200017PCT) used in forming new products. It would also be desirable to have a reaction product composition characterized by one or more of the following: having good stability (e.g., good shelf life without macroscopic phase separation); having low amount of primary amines; suitable for being directly used in subsequent reaction with other materials to form new and useful polymeric articles without the need for costly, cumbersome, lengthy or time consuming separation of the reaction products; and / or having a moderate OH number.SUMMARY OF THE INVENTION

[0007] Disclosed herein is a method comprising forming a reaction mixture. The reaction mixture comprises a waste polymeric product comprising a thermoset having urethane bonds, urea bonds, isocyanurate bonds, or a combination of two or more thereof, a polycarboxylic acid or an anhydride thereof, a first polyether polyol having an average of from 1.8 to 7 hydroxyl groups per molecule and a number average molecular weight of greater than 350, preferably greater than 400 grams / mole, a second polyether polyol having a number average molecular weight of no greater than 350, preferably less than 300, grams / mole wherein at least 50, preferably at least 60, more preferably at least 70, more preferably at least 80, yet more preferably at least 90, still more preferably at least 95, and even more preferably at least 98 mole percent of the hydroxyl groups in the second polyether polyol are secondary alcohol, and reacting the reaction mixture to decompose (chemolyze) the thermoset to form a reaction product composition.DETAILED DESCRIPTION OF THE INVENTION

[0008] The present inventors discovered that it is beneficial, in chemolysis of a waste thermosetting polymeric that comprises urethane, urea, and / or isocyanurate linkages to use of a mixture of a first polyether polyol having a relatively high molecular weight and a second polyether polyol having a lower molecular weight where the second polyether polyol is in majority portion a secondary alcohol. Particularly, the reaction product composition formed from this chemolysis can have good shelf stability and / or can be substantially homogeneous, such that the reaction product composition can be directly used to form new polyurethane products. Furthermore, if at least a portion of the first polyether polyol and second poly ether polyol include polyols having three or more hydroxyl groups per molecule, the reaction product can have an OH number and average functionality (i.e., functionality is number of OH groups per molecule) in a desirable range for forming future cross-linked polyurethanes86171-WO-PCT (DC200017PCT) by reacting the reaction product composition with a polyisocyanate to produce a new polyurethane product, such as a rigid polyurethane foam.

[0009] Particularly, the present inventors also found that if a low molecular weight primary alcohol polyether polyol is present in significant amounts in the reaction mixture at the initial stages of the reaction, the residue of the waste thermosetting polymeric material (e.g., waste polyurethane, waste polyurethane / urea, waste polyurethane / isocyanurate, waste polyurethane / isocyanurate / urea, waste polyurea, waste polyurea / isocyanurate, or waste polyisocyanurate), may not be fully dispersed in the reaction product composition, as evidenced by phase separation and / or precipitation. By “residue” is meant a portion (i.e., chemical group or moiety) of the original waste thermosetting polymeric material after the breaking of the urethane bonds, isocyanurate bonds, and / or urea bonds. Without wishing to be bound by theory, it is believed that a relatively high molecular weight poly ether polyol better facilitates dispersion of the residue of the waste thermosetting polymeric material (e.g., waste polyurethane, waste polyurethane / urea, waste polyurethane / isocyanurate, waste polyurethane / isocyanurate / urea, waste polyurea, waste polyurea / isocyanurate, or waste polyisocyanurate) by reacting with the residue to form a dispersible component in the reaction product mixture. However, when a relatively low molecular weight primary alcohol polyether polyol is used, those molecules react more quickly with the residue but will not provide dispersibility of the residue. In contrast, by using a relatively low molecular weight polyether polyol that is a secondary alcohol the reaction rate of the lower molecular weight polyether polyol with the residue is slower and better balanced with the reaction rate of the relatively high molecular weight polyether polyol thereby providing better dispersion of the residue of waste thermosetting polymeric material (e.g., waste polyurethane, waste polyurethane / urea, waste polyurethane / isocyanurate, waste polyurethane / isocyanurate / urea, waste polyurea, waste polyurea / isocyanurate, or waste polyisocyanurate) in the reaction product mixture. This leads to a reaction product mixture that is more homogeneous and / or has better shelf stability.

[0010] The waste polymeric product comprises as the major component a thermoset polymer comprising urethane, urea, and / or isocyanurate bonds. For example, the waste polymeric product can comprise a polyurethane, a polyurethane / urea, a polyurethane / isocyanurate, a polyurethane / urea / isocyanurate, a polyurea, a polyurea / isocyanurate, or a polyisocyanurate. For example, the waste polymeric product can comprise greater than 50, greater than 60, greater than 70, greater than 80, or greater than 90 and up to 100, up to 99, up to 98, up to 97, up to 96, or up to 95 weight percent (wt%) of the86171-WO-PCT (DC200017PCT) thermoset polymer comprising urethane, urea, and / or isocyanurate bonds (e.g., waste polyurethane, waste polyurethane / urea, waste polyurethane / isocyanurate, waste polyurethane / isocyanurate / urea, waste polyurea, waste polyurea / isocyanurate, or waste polyisocyanurate) based on total weight of the waste product. The remainder of the waste product may include one or more additives (e.g., fillers, catalysts, surfactants, pigments, etc.); impurities; other polymers that had been mixed or blended with the polyurethane; residual amounts from adjacent layers adhered to the polyurethane waste product such as metal foils, craft paper, or polymers, or moisture.

[0011] The waste polymeric product comprising a thermoset polymer comprising urethane, urea, and / or isocyanurate bonds can be any such product which is desired to be recycled. For example, the waste polymeric product can comprise a polyurethane based from any common polyols such as a polyether polyol, a polyester polyol, a polycarbonate polyol, a polyacrylate polyol, a copolymer polyol, a dispersed polyol, a natural oil derived polyol, or a mixture of these types of polyols. As another example, the waste polymeric product to be recycled can be, for example, a flexible polyurethane foam. Notably flexible polyurethane foams typically include both urethane and urea linkages due and can be considered a polyurethane / urea.[00121 While not required, to increase surface area for reaction, the waste polymeric product can be provided in the form of fragments. For example, a polyurethane source (e.g., a polyurethane foam, such as a flexible polyurethane foam) can be cut into pieces and then shredded or chopped to form fragments. The size of the fragments can be, for example, from 0.1, from 0.5, or from 1 up to 100, up to 50, up to 10, or to up 5 millimeters. The waste polymeric product to be converted can initially be in solid form and, if initially in the form of a low density foam, can be pre-processed into a higher density and more compact form to facilitate its loading into a reaction vessel.

[0013] The waste polymeric product can be present in an amount of from 5, from 10, from 20, or from 30 up to 70, up to 60, up to 55, or up to 50 weight percent based on total weight of the reaction mixture. The reaction mixture includes the waste product, the polycarboxylic acid or anhydride, the first polyether polyol, and the second polyether polyol and any optional ingredients. The entire waste polymeric product can be present in the reaction mixture at the beginning of the process, or the waste polymeric product can be added in aliquots over time. The latter approach can facilitate better wetting of the waste polymeric product during a decomposition process. The “initial stage” of the process includes the time86171-WO-PCT (DC200017PCT) up until the entire charge of the waster polymeric product has been added to the reaction mixture.

[0014] The poly carboxy lie acid or anhydride thereof can be for example, phthalic anhydride, phthalic acid, maleic anhydride, maleic acid, fumaric acid, succinic anhydride, succinic acid, alkenylsuccinic anhydrides and acids, (e.g., dodecenylsuccinic anhydride), tetrahydrophthalic anhydride, tetrahydrophthalic acid, methyl tetrahydrophthalic anhydride, methyl tetrahydrophthalic acid, hexahydrophthalic anhydride, hexahydrophthalic acid, methyl hexahydrophthalic anhydride, methyl hexahydrophthalic acid, nadic anhydride, nadic acid, methyl nadic anhydride, methyl nadic acid, citric acid, isocitric acid, or mixtures of two or more thereof. The amount of the polycarboxylic acid or anhydride thereof can be from 1 , from 3, from 5, or from 7 up to 20, up to 17, or up to 15 weight percent based on total weight of the total reaction mixture including the initial reaction mixture, and if later charges are used, the total reaction mixture including initial and subsequent charges of reactants. The polycarboxylic acid or anhydride or a portion of the total amount thereof is provided in the initial stage of the process. However, a portion the polycarboxylic acid or anhydride can be added, for example as a second aliquot, after the initial stage, (e.g., after the final charge of the waste polymeric product, such as 30 minutes, 1 hour or 2 hours after the final charge of the waste polymeric product, or at a time for example, from 2, from 3, from 4, from 5 hours after the beginning of the reaction up to, for example, about 8 hours after the beginning of the reaction). For example, from 1, from 5, from 10, from 15 or from 20 up to 40, up to 35, up to 30 weight percent of the polycarboxylic acid or anhydride based on total weight of the polycarboxylic acid or anhydride used in the chemolysis process can be added at such a later time in the process. For example, when a second portion of the polycarboxylic acid or anhydride is added after the initial stage, (e.g., after the final charge of the waste polymeric product, such as 30 minutes, 1 hour or 2 hours after the final charge of the waste polymeric product , or at a time for example, from 2, from 3, from 4, from 5 hours after the beginning of the reaction up to, for example, about 8 hours after the beginning of the reaction) the weight ratio of the polycarboxylic acid or anhydride in the initial stage of the reaction to the second portion provided after the initial stage can be from 99:1, from 95:5, from 90:10, or from 80:20 up to 60:40, up to 65:35 or up to 70:30. This later addition (e.g., charge or aliquot) can facilitate reduction of aromatic amine content by reaction of the acid or anhydride with the amine that may form during chemolysis reactions.

[0015] The first polyether polyol has an average of from 1.8, from 1.9, from 2, from 2.5, or from 3 up to 7, up to 6, up to 5, or up to 4 hydroxyl groups per molecule and having a86171-WO-PCT (DC200017PCT) number average molecular weight of from greater than 350, or from 400 grams / mole up to 1000, up to 900, up to 800 grams / mole. The first polyether polyol can have an OH number of for example from 100 or from 110 up to 600, or up to 500. The majority of the hydroxyl groups on the first polyether polyol are present as secondary alcohols (i.e., more than 50, more than 60, more than 70, more than 80 up to 100, up to 98, up to 95 mole% of the hydroxyl groups of the first polyether polyols can be secondary alcohols). For example, the first polyether polyol can be or can include a polyol prepared by alkoxylation of an alcohol or a mixture of two and more alcohols with alkylene oxides, e.g., ethylene oxide, propylene oxide, and / or butylene oxide, among others. For example, the first polyether polyol can be or can include a triol. The first polyether polyol can be, for example, a glycerine propoxylated polyether triol. The first polyether polyol can exclude grafted polyether polyols. Commercial examples of materials that can be used as the first polyether polyol include VORANOL™ CP450, VORANOL™ CP 755, VORANOL™ P 400, VORANOL™ 360, VORANOL™ RN 482, TERCAROL™ 8092, VORANOL™ RN 490 (all from Dow Inc.), POLYDO PN-400 from Kukdo Chemical. The first polyether polyol can be present in an amount of from 5, from 7, from 10, from 15 up to 80 up to 70, up to 60, up to 50, up to 40, up to 30, or up to 25 weight percent based on total weight of the total reaction mixture including the initial reaction mixture, and if later charges are used, the total reaction mixture including initial and subsequent charges of reactants. The first polyether polyol can be present in an amount of from 10, from 15, from 20, or from 30 up to 70, up to 60, up to 50, or up to 40, mole% of the total hydroxyl equivalents from polyol in the reaction mixture including the initial reaction mixture, and if later charges are used, the total reaction mixture including initial and subsequent charges of reactants.

[0016] The second polyether polyol has a number average molecular weight of from 70, from 120, from 130, form 140, from 150, from 160, from 170, from 180, from 190 or from 200 up to 350, up to 330, up to 320, up to 310, up to 300, up to 290, or up to 280 grams per mole. The second polyether polyol can have an OH number of, for example, from 650, from 660, from 670, from 680, from 690, or from 700 up to 1500, up to 1200, up to 1100, or up to 1050. The second polyether polyol can have an average of from 1.8, from 1.9, from 2, from 2.2, or from 2.5 up to 7, up to 6, up to 5, up to 4, or up to 3 hydroxyl groups per molecule.

[0017] At least 50, at least 55, at least 60, at least 65, at least 70, at least 80, at least 90, at least 95, at least 96, at least 97, at least 98, at least 99, or 100 mole% of the hydroxyl groups of the second polyether polyol are secondary alcohols. While the reaction mixture can86171-WO-PCT (DC200017PCT) include some low molecular weight (e.g., less than 300) primary alcohol polyols, such as diethylene glycol, those low molecular weight primary alcohol polyols if present preferably should be at amounts less than 10, less than 7, less than 5, less than 3, less than 1, or less than 0.5 weight percent based on total weight of the reaction mixture. The second polyether polyols can have propyloxy or butyloxy groups with the hydroxyl group on the second carbon atom. The second polyether polyols can, for example, be diols such as dipropylene glycol with, for example, at least 90, at least 95, at least 97% being the secondary alcohol isomer. The second polyether polyol can be, for example, tripropylene glycol with, for example, at least 90, at least 95, at least 97% being the secondary alcohol isomer. The second polyether polyol can be, for example, a triol, such as a glycerine propoxylated triol. Other specific examples include propylene glycol (provided it has 50% of OH groups as secondary alcohols) and VORANOL™ CP260 (from Dow Inc.). The second polyether polyol can be present in an amount of from 5, from 8, from 10, from 12 or from 14 up to 40, up to 35, up to 30, or up to 20 weight percent based on total weight of the total reaction mixture including the initial reaction mixture, and if later charges are used, the total reaction mixture including initial and subsequent charges of reactants. The second polyether polyol can be present in an amount of from 10, from 20, from 30, from 40, or from 55 up to 80, up to 75, or up to 70 mol % of the total hydroxyl equivalents from polyol in the reaction mixture including the initial reaction mixture, and if later charges are used, the total reaction mixture including initial and subsequent charges of reactants. The second polyether polyol or a portion of the total amount thereof is provided in the initial reaction mixture. However, a portion of the second polyether polyol can be added, for example as a second aliquot, after the initial stage of the reaction, (e.g., after the final charge of the waste polymeric product, such as 30 minutes, 1 hour or 2 hours after the final charge of the waste polymeric product , or at a time for example, from 2, from 3, from 4, from 5 hours after the beginning of the reaction up to for example about 8 hours after the beginning of the reaction). The weight ratio of the second poly ether polyol added in the initial stage of the reaction to the second portion provided after the initial stage can be from 90:10, from 80:20, or from 75:25 up to 50:50, up to 55:45 or up to 60:40. This later addition (e.g., charge or aliquot) can facilitate esterification of any unreacted acid that may otherwise be in the reaction product.

[0018] The reaction mixture can exclude grafted polyether polyols.

[0019] No catalyst is required for the reaction. However, there can be a catalyst preferably in amounts of from 0.01, from 0.05, from 0.1, or from 0.2 up to 5, up to 4, up to 3, up to 2, up to 1, or up to 0.7 weight percent based on total weight of the reaction mixture. The86171-WO-PCT (DC200017PCT) catalyst can be, for example a metal salt of an organic acid, such a Group I metal of an organic acid preferably having 5-10 carbon atoms, or, as a specific example, potassium octoate; a metal carboxylate, or a metal hydroxide. Other choices for catalyst may include: tin(II) salts of organic carboxylic acids (e.g., tin(II) diacetate); bismuth salts of organic carboxylic acids (e.g., bismuth octanoate); cyclic and / or linear tertiary amines and / or long chain amines (e.g., bis-(2-dimethylaminoethyl)ether; N,N,N',N", N"-pentamethyldiethylene- triamine, triethylamine, tributyl amine; N,N-dimethylaminopropylamine, dimethylethanolamine, N,N,N',N'-tetramethylethylenediamine, dimethylbenzylamine, triethylenediamine); tetraalkylammonium hydroxides (e.g., tetramethylammonium hydroxide); alkali metal hydroxides (e.g., sodium hydroxide); alkali metal alkoxides (e.g., sodium methoxide); and combinations thereof. Some commercially available depolymerization catalysts include POLYCAT® 5, POLYCAT® 8, DABCO® 33-LV, and DABCO® T-12, DABCO® TMR-2, DABCO® TMR-20, DABCO® TMR-30, DABCO® TMR-7, DABCO® K 2097; DABCO® K15, POLYCAT® 41, and POLYCAT® 46 all available from Evonik. The reaction mixture can be free of halide containing catalysts.

[0020] Optional components in the reaction mixture can include a non-ionic surfactant (with or without hydroxyl functionality) including polyols having a block structure of two or more sections of ethylene oxide, propylene oxide, or butylene oxide. For example, a block polyol can be an ethylene oxide / alkylene oxide / ethylene oxide block polyol where the alkylene oxide comprises a propylene oxide or a butylene oxide, having number average molecular weights in the range of from 1000, from 1500 or from 2000 up to 5000, up to 4000, or up to 3000 grams per mole. These optional components, particularly the polyols having a block structure, may also participate in the reaction to some extent. Commercially available examples of such optional components include VORANOL™ 223-060LM, TERGITOL™ L62, VORANOL™ 222-056, DOWFAX™ DF-142, TERGITOL™ L61E, VORANOL™ 3322, DOWFAX™ 63N40 all from Dow Inc. The amount of such optional components can be 0, greater than 0, at least 1 up to 25, up to 20, up to 15, up to 10, or up to 5 weight percent based on total weight of the total reaction mixture including the initial reaction mixture, and if later charges are used, the total reaction mixture including initial and subsequent charges of reactants. The amount of such optional component(s) can be for example 0, or from 0 or from 1 up to 5 or up to 15 mole% of the total hydroxyl equivalents from polyol in the reaction mixture including the initial reaction mixture, and if later charges are used, the total reaction mixture including initial and subsequent charges of reactants.86171-WO-PCT (DC200017PCT)

[0021] The process according to the invention can be carried out, for example, in a corrosion resistant vessel. The vessel can be constructed, for example, from glass or stainless steel. The reaction can be carried out at ambient pressure, so the vessel need not be designed to resist pressures above ambient. The vessel can be equipped with mechanical stirring, for example an impeller type overhead stirrer. The vessel can be equipped with a fractionation or distillation device, for example a distillation column.

[0022] In the process according to the invention, the reaction components (e.g., first polyether polyol, first portion of second polyether polyol, first portion of dicarboxylic acid, and any optional components) can be heated to an initial temperature from 120, from 140, or from 160 up to 230, up to 220, or up to 210°C. The thermoset polymer waste (e.g., polyurethane, polyurethane / urea, polyurethane / isocyanaurate) can be metered into the heated mixture to form the reaction mixture. During the metering process, the reaction mixture can be maintained at a temperature of from 120, from 140, or from 160 up to 230, up to 220, or up to 210°C. After all thermoset polymer waste is added to the reactor, the reaction mixture can be heated and stirred for an additional 30 minutes, 1 hour or 2 hours, or until a time for example, from 2, from 3, from 4, from 5 hours after the beginning of the reaction up to for example about 8 hours after the beginning of the reaction. During this step the reaction temperature can be maintained at a level from 140, from 150, from 160, or from 170 up to 240, or up to 230°C. At this point a portion of the second polyether polyol can be added, for example as a second aliquot. In addition, a portion of the polycarboxylic acid or anhydride can be added, for example as a second aliquot. After this, the reaction mixture can be heated for from 15, from 30, or from 60 minutes up to 4, up to 3, or up to 2.5 hours. During this step the reaction temperature can maintained at a level from 140, from 150, from 160, or from 170 up to 240, or up to 230°C. After this, the reaction mixture can be allowed to cool to room temperature and may be directly used in subsequent polymerization reactions (such as forming a new polyurethane foam) without further purification.

[0023] The reaction mixture can be free of or substantially free of water. For example, the reaction mixture can have less than or equal to 0.2, less than or equal to 0.15, less than or equal to 0.1, or less than or equal to 0.05 weight percent water, based on total weight of the reaction mixture. The method can be run without the addition of water.

[0024] The reactants can be heated by any suitable means, including convection, conduction, radiation or a combination thereof. No radiation (e.g., microwave radiation) is needed for a rapid acidolysis of the polyurethane. The reaction temperature can be from 120, from 130, from 140, from 150, from 160, or from 170 up to 240, up to 230, or up to 220°C.86171-WO-PCT (DC200017PCT)

[0025] The reaction product mixture is preferably homogeneous or substantially homogeneous liquid (solution or dispersion). The reaction product mixture can preferably include the following imides species, and / orwherein where each of Ri and R3 is a bond (could be a single or double bond), an aromatic group (e.g., having 5 to 12 carbon atoms, preferably linked in the ortho position to the adjacent N atoms, a cycloaliphatic group (e.g., having 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 carbon atoms) and preferably linked to the adjacent atoms at 1,2 positions , or an aliphatic group (e.g., having 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12 carbon atoms. Ri and R3 can be the same or can be different in different occurrences within the molecule and where R2is a group originating from the isocyanate(s) used in preparing the polyurethane, polyurethane / urea, or polyurea of the waste product. R2can include aromatic, cycloaliphatic, and / or aliphatic groups such as, for example, divalent radicals of benzene, toluene, tetramethylxylene, naphthalene, (poly)methylenediphenyl, (poly)dicyclohexylmethane, hexane, cyclohexane, or isophorone. R2can be the same or can be different in different occurrences within the molecule. The reaction product will also include various polyol species that do not include imide structures such as, for example polyols liberated from the polyurethane / polyurea waste product, polyether polyol reactants or polyols form be reaction thereof.

[0026] The reaction product mixture can have a viscosity of from 100, from 2000, or from 3000 up to 50000, up to 40000, up to 30000, or up to 20000 centipoise at 25°C. The viscosity can be measured on a cone and plate viscometer such as a Brookfield DV-II+ viscometer with revolutions per minute (rpm) chosen such that the torque of the viscometer is between 10 and 90% of its operating range, preferably 50%, according to ASTM D4878-23.

[0027] The reaction product mixture can have a number average molecular weight of from 300, or from 350 up to 1000, up to 800 or up to 700 g / mol; a weight average molecular weight of from 600 up to 5000 g / mol, and a z average molecular weight of from 1500 up to 30,000 g / mol.

[0028] Number average molecular weight (Mn), weight average molecular weight (Mw), z average molecular weight (Mz), and polydispersity index (PDI) = Mw / Mn)) are determined according to the procedure described in ASTM D5296-19. This method uses Gel86171-WO-PCT (DC200017PCT)Permeation Chromatography (GPC); an Agilent 1200 HPLC system with a PLgel Guard Column and four PLgel narrow porosity columns (5 Dm, 300 mm x 7.5 mm) (50 Angstrom (A); 100 A; 1,000 A; and 10,000 A); and a ReadyCal Polyethylene Glycol Calibrant Set (44000-238 Mp) utilizing uninhibited tetrahydrofuran (THF). The samples used for the molecular weight measurement were prepared at a concentration of 0.1 g / 10 mL THF.

[0029] The reaction product mixture can have less than 5000, less than 4000, less than 3000, or less than 2000 parts by weight per million of water based on total weight of the reaction product mixture. Water content can be measured by coulometric titration according to ASTM D4672-24.

[0030] The reaction product mixture can have an OH number of from 100 or from 125 or from 150 up to 375 or up to 350 or up to 300 mg KOH / gram. OH number or hydroxyl number (OH#) is determined according to the procedure described in ASTM El 899- 16 for the standard test method for hydroxyl groups using reaction with p-toluenesulfonyl isocyanate and potentiometric titration with a Mettler T70 titration system using tetrabutylammonium hydroxide.

[0031] The reaction product mixture can have a basic amine content (indicative of the amount of undesirable primary amines) of less than 0.7, less than 0.6, less than 0.5, less than 0.4, less than 0.3, less than 0.2, or less than 0.1 milliequivalents per gram as measured according to ASTM D6979-18. The measurement can be made utilizing, for example, a Mettler T7 Titration System.

[0032] The reaction product mixture can show good shelf life stability. For example, the reaction product mixture can show no macroscopic (visual inspection) phase separation when inspected in a 10 ml graduated cylinder after aging at 55°C for 30 days. For example, stability of recycled polyols can be assessed by evaluating macroscopic phase separation of samples aged in graduated cylinders and recording relative volumes of top and bottom phases. Recycled polyol blends can be mixed in a FlackTek speedmixer at 1500 rpm for 30 seconds. Approximately 8 mL of polyol can be then immediately poured into a 10 mL graduated cylinder. The samples can be then placed in a 55 °C oven to further accelerate aging. After 30 days at 55 °C, phase separation can be evaluated by visual inspection for these samples.

[0033] The reaction product mixture can be reacted with a polyisocyanate to form a new polyurethane based product. For example, a reaction product mixture as disclosed herein having, for example, an OH number of from 100 or from 125 or from 150 up to 375 or up to 350 or up to 300 mg KOH / gram can be reacted with a polyisocyanate such as86171-WO-PCT (DC200017PCT) polymethylene polyphenylisocyanate in the presence of other optionally additives known to skilled in the art such as a blowing agent, a surfactant, a catalyst, a flame retardant, a filler, a pigment, etc. to form a rigid polyurethane or polyisocyanurate insulating foam. The stoichiometric ratio of the isocyanate groups in the polyisocyanate component to the hydroxyl groups from the reaction product mixtures and other optional components (e.g., an additional polyol, water, and the like) can be between 1.0 and 6. This ratio multiplied by 100 is typically referred as isocyanate index. The isocyanate index of the foam-forming composition comprising the reaction product mixture of the present invention can be from 100, from 120, from 150, from 175, from 200, or from 250 up to 600, up to 575, up to 550, up to 500, up to 475, or up to 450.

[0034] As a specific example of such subsequent reaction, the reaction product mixture can be used to produce a rigid polyurethane foam product. The rigid polyurethane foam can have a density of, for example, from 20, from 25, or from 30 kg / m3up to 200, up to 150, up to 100, up to 75, or up to 60 kg / m3in one general embodiment. Some of the advantageous properties exhibited by the resulting foam product produced according to the present invention, can include, for example: good thermal insulation, good mechanical strength and toughness, and high recycling content.

[0035] The rigid polyurethane foam product can exhibit a low thermal conductivity (or “K-factor”) and can for example have a K-factor of less than or equal to 28, less than or equal to 25, or less than or equal to 22 mW / m-K, at 10°C. K-factor is measured on foam specimens having dimensions of 20 cm x 20 cm x 2.5 cm at 50 °F (10 °C) according to ASTM C518-04 (2010). The insulating foam can have a compression strength of at least 80 kPa as measured according to ASTM D- 1621-16.EXAMPLESMaterials

[0036] VORANOL™ 8136 (from DOW Inc.) is a glycerine-initiated, hetereopolymer triol with hydroxyl number of 54 mg KOH / g for use in preparing flexible polyurethane slabstock foams.

[0037] VORASURF™ DC 5986 (from Dow Inc) is a silicone surfactant.

[0038] DABCO™ 33LV (from EVONIK) is 33% triethylenediamine in dipropylene glycol.

[0039] DABCO™ BL11 (from EVONIK) is 70% bis(N,N-dimethylaminoethyl)ether in dipropylene glycol.86171-WO-PCT (DC200017PCT)

[0040] DABCO™ T-9 (from EVONIK) is stannous octoate.

[0041] VORANATE™ T80 — 80:20 mixture of the 2,4 and 2,6 isomers of toluene diisocyanate.

[0042] Voranol™ CP450 is a glycerine initiated propoxylated poly ether polyol having a functionality of 3.0 and a hydroxyl number of 383 mg KOH / g.

[0043] Voranol™ CP260 is a glycerine initiated propoxylated polyether polyol having a functionality of 3.0 and a hydroxyl number of 662 mg KOH / g.

[0044] Nonionic Surfactant 1 is a polyether polyol-based nonionic surfactant made from a 72:28 ratio of polypropylene oxide: polyethylene oxide with hydroxyl number of 45 mg KOH / g.

[0045] PEG200 is polyethylene glycol with number average molecular weight of 200.

[0046] Polyester A is an aromatic polyester polyol having a functionality of 2.0 and a hydroxyl number of 220 mg KOH / g.

[0047] Polyester B is an aromatic polyester polyol having a functionality of 2.4 and a hydroxyl number of 315 mg KOH / g.

[0048] Catalyst 1, 2, 3 and 4 are Polycat™ 5, TMR™ 31, Polycat™ 8 and Dabco™ K2097, respectively, all available from Evonik.

[0049] Additive 1 is a flame retardant, tris(chloropropyl) phosphate (TCPP), available as Fyrol™ PCF from 1CL.

[0050] Isocayanate 1 is polymethylene polyphenylisocyanate with number average molecular weight of 360 g / mol and average isocyanate functionality of 2.7 (Voranate™ M229 from Dow Inc.).Example 1 - Preparation of Flexible Foam (a polyurethane / urea) pieces for recycling

[0051] A flexible foam sheet of 2.54 cm thickness was cut from a foam block and then densified at 125°C and 20 tons of pressure for 5 minutes using a Carver hydraulic press. The densified foam sheet was cut into a number of small pieces having largest dimension no greater than 7 mm (typically pieces of about 2x2x6 mm) for subsequent chemolysis. The flexible foam had been prepared from the following ingredients; 100 parts VORANOL™ 8136, 4.5 parts water, 0.8 parts VORASURF™ DC 5986, 0.11 parts DABCO™ 33LV - 33% triethylenediamine in dipropylene glycol, 0.04 parts DABCO™ BL11 - 70% bis(N,N- dimethylaminoethyl)ether in dipropylene glycol, 0.20 parts DABCO™ T-9 - stannous octoae, 56.08 parts VORANATE™ T80 toluene diisocyanate.Example 2 - Chemolysis procedure86171-WO-PCT (DC200017PCT)

[0052] Chemolysis of the pieces of the densified foam was undertaken using the ingredients shown in Table 1. Into a 4 neck, 500 mL glass reactor is loaded with phthalic anhydride; VORANOL™ CP 450 glycerine propoxylated polyether triol with a number average molecular weight of 450 (the first polyether polyol), one or more low molecular weight polyether polyols (PEG 200 a polyethylene glycol of average molecular weight 200; Voranol CP260 a polyether triol secondary alcohol, or tripropylene glycol (98% secondary alcohol isomer)), and optional non-ionic surfactant 1, optional 30% hydrogen peroxide, and optional DABCO KI 5 catalyst (70% potassium octoate in diethylene glycol). The reactor had an overhead turbine-type blade stirrer and stir bearing inserted along with stopper, N2 inlet adaptor, Dean-Stark type distillation trap (heat traced & insulated) & condenser, with gentle N2 sweep via inlet adaptor and exiting through trap and condenser. The reactor was warmed by a temperature controlled oil bath held at 65°C for 1.5 hours, then ramped to 180-190°C and addition of the polyurethane / urea foam pieces in 1 to 3 gram aliquots, waiting for the previous aliquot to be completely wetted by the liquid reaction mixture and the disappearance of visible solid pieces before subsequent aliqouts are added. Upon completing foam addition, the temperature was increased to 210°C and held for 2 hours. An additional amount of phthalic anhydride, maleic anhydride, and diethylene glycol or dipropylene glycol (98% secondary alcohol isomer) were added to the reactor with reaction continuing another 2 hours at 210°C before cooling. The reaction product mixture was characterized and tested for viscosity, molecular weight, OH number, nitrogen content, amount of residual water, and shelf stability as described herein. Notably for shelf stability the reaction product mixture was first mixed in a mixer such as a FlackTek™ mixer and then placed into the graduated cylinder and aged at 55 °C for 30 days and then observed by a visual inspection.86171-WO-PCT (DC200017PCT)TABLE la86171-WO-PCT (DC200017PCT)TABLE lbNT = not testedExample 3 - Preparation of Rigid Polyurethane Foam using reaction product mixture.

[0056] Foams are made from formulations as set forth in Table 2. Comparative foam F-A does not contain a recycled polyol. In two inventive foam cases (F-l and F-2), a recycled polyol, i.e., a reaction product mixture of this invention, is mixed with other polyols, surfactant, water, catalysts and flame retardant additive using a high-speed laboratory mixer. For comparative foam F-B, the reaction product composition from Comparative A of Example 2 Table 1 was mixed in a FlackTek™ mixer before combining with the other ingredients due to the macroscopic phase separation observed in this recycled polyol. The physical blowing agent (cyclopentane) is then mixed in, followed by the addition of a polyisocyanate. The resulting reaction mixture is mixed at high speed for 5 seconds and then immediately poured into a vertically oriented 30 cm x 20 cm x 5 cm mold which is preheated to 55°C. The reaction mixture is permitted to react in the mold for 20 minutes, at which time the resulting foam is demolded.

[0057] Test specimens were cut from the middle interior section of each foam for testing after the foams are conditioned overnight in room temperature air. Foam core density is calculated on the basis of weight and physical dimensions of specimens used for K- factor measurements. K-factor is measured according to ASTM C518-21. Compressive strength is86171-WO-PCT (DC200017PCT) measured according to ASTM DI 621-16. Results of the property testing are as indicated in Table 2.Table 2. Rigid Foams Prepared from Comparative and Inventive Repolyols

[0058] This disclosure further encompasses the following aspects.

[0059] Aspect 1. A method comprising forming a reaction mixture comprising a waste polymeric product comprising a thermoset having urethane bonds, urea bonds, isocyanurate bonds, or a combination of two or more thereof, a polycarboxylic acid or an anhydride thereof, a first polyether polyol having an average of from 1.8 to 7 hydroxyl groups per molecule and having a number average molecular weight of greater than 350, preferably greater than 400 grams / mole, a second polyether polyol having a number average molecular weight of no greater than 350, preferably less than 300, grams / mole wherein at least 50, preferably at least 60, more preferably at least 70, more preferably at least 80, yet more preferably at least 90, still more preferably at least 95, and even more preferably at least 98 mole percent of the hydroxyl groups in the second polyether polyol are secondary alcohol,86171-WO-PCT (DC200017PCT) and reacting the reaction mixture to decompose the thermoset to form a reaction product composition.

[0060] Aspect 2. The method of Aspect 1 wherein the second polyether polyol d) is a propylene glycol, polypropylene glycol, a glycerine propoxylated triol, or mixtures of two or more thereof.

[0061] Aspect 3. The method of Aspect 1 wherein at least a portion of the first poly ether polyol c), the second polyether polyol d), or a portion of both the first polyether polyol c) and the second poly ether polyol d comprise triols.

[0062] Aspect 4. The method of any one of the preceding Aspects wherein the polycarboxylic acid or anhydride comprises phthalic anhydride, phthalic acid, maleic anhydride, maleic acid, succinic anhydride, succinic acid, an alkenylsuccinic anhydride, an alkenyl succinic acid, tetrahydrophthalic anhydride, tetrahydrophthalic acid, methyl tetrahydrophthalic anhydride, methyl tetrahydrophthalic acid, hexahydrophthalic anhydride, hexahydrophthalic acid, methyl hexahydrophthalic anhydride, methyl hexahydrophthalic acid, nadic anhydride, nadic acid, methyl nadic anhydride, methyl nadic acid, citric acid, isocitric acid, or mixtures of two or more thereof.

[0063] Aspect 5. The method of any one of the preceding Aspects wherein the waste polymeric product comprises a flexible polyurethane foam.

[0064] Aspect 6. The method of any one of the preceding Aspects wherein the reaction mixture comprises based on total weight of the reaction mixture from 5 to 60 weight percent of the waste polymeric product, from 1 to 20 weight percent of the polycarboxylic acid or the anhydride thereof, from 5 to 80 weight percent of the first polyether polyol, from 5 to 40 weight percent of the second polyether polyol, from 0 to 5 weight percent of a catalyst, and from 0 to 25 weight percent of a polyol having ethylene oxide capped polyalkylene oxides where in the polyalkylene oxides comprise repeat units -R-O- where each R can be independently comprised of 3 to 4 carbon atoms.

[0065] Aspect 7. The method of Aspect 6 wherein a first portion of the polycarboxylic acid or the anhydride is provided in an initial reaction stage and a second portion of the polycarboxylic acid or the anhydride is provided after reacting the initial reaction mixture for a period at least one hour after a final addition of the polymeric waste product and where a weight ratio of the first portion to the second portion is from 99: 1 to 60:40.

[0066] Aspect 8. The method of Aspect 6 or 7 wherein a first portion of the second polyether polyol is provided in an initial reaction stage and a second portion of the second86171-WO-PCT (DC200017PCT) polyether polyol is provided after reacting the initial reaction mixture for a period at least one hour after a final addition of the polymeric waste product wherein the second portion of second polyether polyol and where a weight ratio of the first portion to the second portion is from 90:10 to 50:50.L0067 J Aspect 9. The method of any one of the preceding Aspects wherein an amount of water present in the reaction mixture is less than 0.15, preferably less than 0.1, more preferably less than 0.05 weight percent based on total weight of the reaction mixture.

[0068] Aspect 10. The method any one of the preceding Aspects wherein no water is added to the reaction mixture.

[0069] Aspect 11. The method of any one of the preceding Aspects wherein the reaction product composition has an OH number of from 100 to 375, preferably 125 to 350 mg KOH per gram.

[0070] Aspect 12. The method of any one of the preceding Aspects wherein the amount of basic nitrogen in the reaction produce is less than 0.7, preferably less than 0.6, more preferably less than 0.5, still more preferably less than 0.4, yet more preferably less than 0.3, even more preferably less than 0.2 milliequivalents per gram.

[0071] Aspect 13. The method of any one of the preceding Aspects wherein the amount of water in the reaction product composition is less than 2000 parts by weight per million parts by weight of the reaction product.

[0072] Aspect 14. The method of any one of the preceding Aspects wherein the reaction product composition is shelf stable as indicated by no macroscopic phase separation after aging at 55 °C for 30 days.

[0073] Aspect 15. The method of any one of the preceding Aspects wherein the reaction occurs in the absence of any halide-containing catalyst.

[0074] Aspect 16. The method of any one of the preceding Aspects further comprising reacting the reaction product composition with a polyisocyanate to form a new polyurethane product.

[0075] Aspect 17. The method of Aspect 16 wherein the new polyurethane product is a rigid polyurethane foam.

[0076] Aspect 18. A composition made by the method of any one of Aspects 1-15.

[0077] Aspect 19. An article made by the method of Aspect 16 or 17.

[0078] All ranges disclosed herein are inclusive of the endpoints, and the endpoints are independently combinable with each other (e.g., ranges of “up to 25 wt.%, or, more specifically, 5 wt.% to 20 wt.%”, is inclusive of the endpoints and all intermediate values of86171-WO-PCT (DC200017PCT) the ranges of “5 wt.% to 25 wt.%,” etc.). Moreover, stated upper and lower limits can be combined to form ranges (e.g., “at least 1 or at least 2 weight percent” and “up to 10 or 5 weight percent” can be combined as the ranges “1 to 10 weight percent”, or “1 to 5 weight percent” or “2 to 10 weight percent” or “2 to 5 weight percent”).

[0079] The disclosure may alternately comprise, consist of, or consist essentially of, any appropriate components herein disclosed. The disclosure may additionally, or alternatively, be formulated so as to be devoid, or substantially free, of any components, materials, ingredients, adjuvants or species used in the prior art compositions or that are otherwise not necessary to the achievement of the function and / or objectives of the present disclosure.

[0080] All cited patents, patent applications, and other references are incorporated herein by reference in their entirety. However, if a term in the present application contradicts or conflicts with a term in the incorporated reference, the term from the present application takes precedence over the conflicting term from the incorporated reference.

[0081] Unless specified to the contrary herein, all test standards are the most recent standard in effect as of the filing date of this application, or, if priority is claimed, the filing date of the earliest priority application in which the test standard appears.

Claims

86171-WO-PCT (DC200017PCT)What is claimed is:

1. A method comprising forming a reaction mixture comprising a) a waste polymeric product comprising a thermoset having urethane bonds, urea bonds, isocyanurate bonds, or a combination of two or more thereof, b) a polycarboxylic acid or an anhydride thereof, c) a first poly ether polyol having an average of from 1.8 to 7 hydroxyl groups per molecule and having a number average molecular weight of greater than 350 grams / mole, d) a second polyether polyol having a number average molecular weight of no greater than 350 grams / mole wherein at least 50 mole percent of the hydroxyl groups in the second poly ether polyol based on total moles of hydroxyl groups in the second polyether polyol are secondary alcohols, reacting the reaction mixture to decompose the thermoset to form a reaction product composition.

2. The method of claim 1 wherein the second polyether polyol d) is a propylene glycol, polypropylene glycol, a glycerine propoxylated triol, or mixtures of two or more thereof.

3. The method of claim 1 wherein at least a portion of the first poly ether polyol c), the second polyether polyol d), or a portion of both the first polyether polyol c) and the second polyether polyol d) comprises a triol.

4. The method of any one of the preceding claims wherein the polycarboxylic acid or anhydride comprises phthalic anhydride, phthalic acid, maleic anhydride, maleic acid, fumaric acid, succinic anhydride, succinic acid, an alkenylsuccinic anhydride, an alkenyl succinic acid, tetrahydrophthalic anhydride, tetrahydrophthalic acid, methyl tetrahydrophthalic anhydride, methyl tetrahydrophthalic acid, hexahydrophthalic anhydride, hexahydrophthalic acid, methyl hexahydrophthalic anhydride, methyl hexahydrophthalic acid, nadic anhydride, nadic acid, methyl nadic anhydride, methyl nadic acid, citric acid, isocitric acid, or mixtures of two or more thereof5. The method of any one of the preceding claims wherein the waste polymeric product comprises a flexible polyurethane foam.86171-WO-PCT (DC200017PCT)6. The method of any one of the preceding claims wherein the reaction mixture comprises based on total weight of the reaction mixture from 5 to 60 weight percent of the waste polymeric product, from 1 to 20 weight percent of the polycarboxylic acid or the anhydride thereof, from 5 to 80 weight percent of the first polyether polyol, from 5 to 40 weight percent of the second polyether polyol, from 0 to 5 weight percent of a catalyst, and from 0 to 25 weight percent of a polyol having ethylene oxide capped polyalkylene oxides wherein the polyalkylene oxides comprise repeat units -R-O- where each R can be independently comprised of 3 to 4 carbon atoms.

7. The method of claim 6 wherein a first portion of the polycarboxylic acid or the anhydride is provided in an initial reaction stage and a second portion of the polycarboxylic acid or the anhydride is provided after reacting the initial reaction mixture for a period at least one hour after a final addition of the polymeric waste product and where a weight ratio of the first portion to the second portion is from 99:1 to 60:40.

8. The method of claim 6 or 7 wherein a first portion of the second polyether polyol is provided in an initial reaction stage and a second portion of the second polyether polyol is provided after reacting the initial reaction mixture for a period at least one hour after a final addition of the polymeric waste product wherein the second portion of second polyether polyol and where a weight ratio of the first portion to the second portion is from 90: 10 to 50:

509. The method of any one of the preceding claims wherein the reaction product composition has an OH number of from 100 to 375 mg KOH per gram.

10. The method of any one of the preceding claims wherein the amount of basic nitrogen in the reaction produce is less than 0.7 milliequivalents per gram.

11. The method of any one of the preceding claims wherein the amount of water in the reaction product composition is less than 2000 parts by weight per million parts by weight of the reaction product.

12. The method of any one of the preceding claims wherein the reaction product composition is shelf stable as indicated by no macroscopic phase separation after aging at 55°C for 30 days.

13. The method of any one of the preceding claims further comprising reacting the reaction product composition with a polyisocyanate to form a new polyurethane product.

14. The method of claim 13 wherein the new polyurethane product is a rigid polyurethane foam.

15. A composition made by the method of any one of claims 1-12.86171-WO-PCT (DC200017PCT)16. An article made by the method of claim 14 or 15.