Polyurethane derived from depolymerized lignin containing lignin monomers

Abstract

The present invention provides a method for producing thermosetting polyurethane. [Solution] A polyurethane is produced by reacting (a) a diisocyanate composition, (b) depolymerized lignin containing lignin-derived monomers or products obtained by the functionalization of each thereof, (c) optionally a polyol composition, (d optionally a chain extender), and (e) optionally an additive. More specifically, this process is produced by using depolymerized lignin containing 4-hydroxylalkylphenol or 4-alkylphenol and their derivatives in varying amounts. The polyurethane can be partially or entirely bio-based.

Description

[Technical Field]

[0001] The present invention generally relates to polyurethanes based on the reaction of (a) a diisocyanate composition, (b) a depolymerized lignin composition containing lignin-derived monomers or products obtained by the functionalization of each thereof, (c) optionally a polyol composition, (d) optionally one or more chain extenders, and (e) optionally one or more additives. More specifically, the process relates to the use of depolymerized lignin containing 4-hydroxylalkylphenol or 4-alkylphenol and derivatives thereof in varying amounts. The polyurethanes of the present invention can be partially or entirely bio-based. Furthermore, the present invention relates to methods for preparing these polyurethanes and their use. [Background technology]

[0002] Polyurethanes are polymers widely used, particularly in applications such as coatings, molded articles, foams (rigid and flexible), sealants, and synthetic fibers. Current synthetic polyurethanes are the result of reactions between diisocyanates or polyisocyanates and hydroxyl group-containing monomers, such as diols, triols, or polyols.

[0003] Lignin is the second largest biopolymer on Earth after cellulose, but unlike the latter, lignin is currently undervalued. Due to its high content of hydroxyl groups (both aliphatic and aromatic), lignin is being sought as a polyol substitute in polyurethane synthesis (Non-Patent Literature 1). However, lignin derived from the isolation of cellulose, also known as industrial lignin, has a high molecular weight and is polydispersible due to the condensation reaction that occurs under the harsh reaction conditions of cellulose isolation. As a result, these types of lignin typically yield poor-performing polymers.

[0004] On the one hand, by depolymerizing or fractionating lignin, a low molecular weight oligomer with an increased hydroxyl functionality can be obtained, which results in a polyurethane polymer with improved properties. This concept has been described in several scientific papers and patent publications (Non-Patent Document 2, Non-Patent Document 3, and Patent Document 1). Patent Document 2 and Patent Document 3 disclose chemically modifying depolymerized lignin before using it in polyurethane synthesis.

[0005] Despite the advantages of depolymerized lignin over non-depolymerized lignin, high temperatures and acidic / basic media are still used in most depolymerization protocols, resulting in low monomer yields. Based on mild fractionation and / or depolymerization conditions and strategies to stabilize the intermediates formed during depolymerization, a new technology has recently been developed that enables the production of lignin oil containing lignin-derived monomers in good yields and selectivities (Non-Patent Document 4, Non-Patent Document 5). These monomers can be divided into two main categories based on the alkyl chain end groups: 4-alkylphenol and 4-hydroxylalkylphenol. Depolymerized lignin oil contains low molecular weight dimers and oligomers in addition to monomers. The exact structure of each component is still unknown, but some have been characterized (Non-Patent Document 6).

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Non-Patent Documents

[0007]

Non-Patent Document 1

Non-Patent Document 2

Non-Patent Document 3

Non-Patent Document 4

Non-Patent Document 5

Non-Patent Document 6

Summary of the Invention

[0008] The present invention generally relates to the use of depolymerized lignin oil containing 4-hydroxyalkylphenol and / or 4-alkylphenol (Formula Ia) and / or their functionalized derivatives (Formula Ib), represented as lignin-derived monomers of Formula I, in polyurethane synthesis.

[0009]

Chemical Formula

[0010] [Chemical formula] 4-Hydroxyalkylphenol (R = OH) 4-Alkylphenol (R = CH3) Formula Ia [Chemical formula] Functionalized 4-hydroxyalkylphenol (R = OH) Functionalized 4-alkylphenol (R = CH3) Formula Ib (In the formula, R represents OH or CH3, R 1 and R 2 each independently represents H or alkyl, particularly H or C 1-6 alkyl, more particularly H or CH3, R 3 and R 4 each independently represents H or oxyalkyl, particularly H or oxyC 1-6 alkyl, more particularly H or OCH3, n is 0 to 3, m is 1 to 12)

[0011] By the depolymerization of lignin, lignin oil containing monomers in a variable amount from less than 5% to a maximum of 50% by weight is obtained. The monomer content can be further increased by extraction and separation processes. Depending on the proportion of monomers in the mixture, the properties of the polyurethane formed therefrom are different. The lower the proportion of monomers, the higher the crosslinking degree of the polyurethane and the formation of a thermosetting polymer. When the proportion of monomers increases, the crosslinking degree decreases, thereby showing the behavior of an elastomer / rubber. When the proportion of monomers becomes very high (more than 90% to 95%), the polyurethane can also become a thermoplastic polyurethane. Therefore, by adjusting the monomer content in the depolymerized lignin, it becomes possible to adjust the properties of the polyurethane manufactured therefrom.

[0012] The monomers in depolymerized lignin oil act as chain extenders in polyurethane synthesis, while other components of depolymerized lignin oil (dimers, trimers, and oligomers) act as crosslinking agents. Therefore, the use of depolymerized lignin oil allows for significant substitution of petroleum-derived diols in polyurethane synthesis, to the point where the polyol portion is completely replaced by depolymerized lignin oil or its derivatives.

[0013] To our understanding, there is no prior art concerning the use of structures represented by formula I in polyurethane synthesis, nor is there any prior art concerning the functionalization of these structures for subsequent use in polyurethane synthesis.

[0014] Accordingly, the present invention aims to provide the use of a depolymerized lignin oil containing a lignin-derived monomer of formula (I) as a chain extender or chain arrester in polyurethane synthesis. As will be further detailed below, depending on the additional reagents used, this polyurethane may be either a thermosetting polyurethane or a thermoplastic polyurethane, but the invention will focus particularly on the synthesis of a thermosetting polyurethane.

[0015] Depolymerization of lignin can yield a lignin oil containing the 4-hydroxyalkylphenol and / or 4-alkylphenol monomer described in formula Ia. The 4-hydroxyalkylphenol and 4-alkylphenol monomer can be functionalized to convert aromatic OH groups to aliphatic OH groups. 4-hydroxyalkylphenol or its derivatized product (formula Ib) can be used as a short-chain diol (also called a chain extender) in polyurethane synthesis. 4-alkylphenol or its derivatized product (formula Ib) can be used as a chain termination agent in polyurethane synthesis. Other components of the depolymerized lignin oil (e.g., dimers, trimers, and oligomers) act as crosslinking agents in thermosetting polyurethane synthesis.

[0016] The polymerization reaction mixture comprises a lignin-derived component, an isocyanate, particularly a diisocyanate, and optionally a diol or polyol. This composition optionally includes additional chain extenders, and optionally one or more catalysts are added. The chemical and physical properties of the polyurethane can be fine-tuned by varying the types and ratios of the various reagents used in the polymerization reaction. The range of polyurethanes obtainable by the method of the present invention covers polyurethanes ranging from rigid thermosetting polyurethanes to thermoplastic polyurethanes. The method for synthesizing polyurethanes (or more) according to the present invention can be carried out using conventional apparatus, catalysts, and processes. In this process, various components can be bio-based. Polyurethanes based on the lignin-derived monomer of formula (I) can serve as a substitute for petroleum-based polyurethanes, enabling the synthesis of fully or partially bio-based polyurethanes.

[0017] Standard polymerization techniques can be used in the synthesis of polyurethanes from depolymerized lignin oil containing monomers as defined herein. These techniques include foam production, molding, reaction extrusion, batch processing, solution polymerization, reaction injection molding, and cast polymerization.

[0018] In one embodiment, the present invention provides a polyurethane synthesized from a lignin-derived monomer. In the production of the polyurethane according to the present invention, the lignin-derived monomer can be used in a purified form or as a composition containing depolymerized lignin, which contains one or more lignin-derived monomers. Thus, in one embodiment, the present invention relates to a polyurethane comprising a reaction product of an isocyanate and a composition containing depolymerized lignin containing a lignin-derived monomer according to formula (I). [ka] Equation I (In the formula, R represents OH or CH3, R 1 and R 2These are independently H or alkyl, particularly H or C 1-6 Alkyl, and more particularly H or CH3, R 3 and R 4 These are independently H or oxyalkyl, particularly H or oxyC 1-6 Alkyl, and more specifically H or OCH3, R 5 is H or hydroxyalkyl, especially hydroxyC 1-12 Represents alkyl, n is between 0 and 3.

[0019] The isocyanates used in the synthesis of polyurethanes from lignin-derived monomers can be selected from the group including aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, or any mixture thereof.

[0020] In certain embodiments, the lignin-derived monomer used in polyurethane synthesis is a monomer of formula (Ia) obtained from the depolymerization of lignin. [ka] Equation (Ia) (In the formula, R represents OH or CH3, R 1 and R 2 These are independently H or alkyl, particularly H or C 1-6 Alkyl, and more particularly H or CH3, R 3 and R 4 These are independently H or oxyalkyl, particularly H or oxyC 1-6 Alkyl, and more specifically H or OCH3, n is between 0 and 3.

[0021] In another specific embodiment, the lignin-derived monomer used in polyurethane synthesis is a monomer of formula (Ib) obtained from the depolymerization of lignin. [ka] Formula Ib (In the formula, R represents OH or CH3, R 1 and R 2 These are independently H or alkyl, particularly H or C 1-6 Alkyl, and more particularly H or CH3, R 3 and R 4 These are independently H or oxyalkyl, particularly H or oxyC 1-6 Alkyl, and more specifically H or OCH3, n is between 0 and 3. m is between 1 and 12.

[0022] When prepared from a composition containing depolymerized lignin, the composition preferably contains at least 10% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib).

[0023] Therefore, in one particular embodiment, the polyurethane according to the present invention is prepared from a composition containing at least 10% by weight of a monomer of formula (Ia) obtained from the depolymerization of lignin, and an isocyanate.

[0024] In another specific embodiment, the polyurethane according to the present invention is prepared from a composition containing at least 10% by weight of a monomer of formula (Ib) obtained from the depolymerization of lignin, and an isocyanate.

[0025] In one embodiment, the composition used in the polyurethane synthesis according to the present invention, which contains at least 10% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib), is a depolymerized lignin oil containing at least 10% by weight and up to about 90% by weight of the above lignin-derived monomer. In a preferred embodiment, a depolymerized lignin oil containing at least 10% by weight and up to about 90% by weight of a lignin-derived monomer according to formula (Ia) is used.

[0026] In addition to the simple polymerization reaction of lignin-derived monomers as defined herein, further reagents, such as polyhydroxy compounds and / or further additives, may be included in the reaction mixture. Thus, in one embodiment, the polyurethane according to the present invention comprises a reaction product of a composition comprising (a) depolymerized lignin containing one or more lignin-derived monomers according to any one of formula (I), formula (Ia), or formula (Ib), (b) isocyanate, (c) optionally one or more polyhydroxy compounds, and (d) optionally one or more additives.

[0027] By adding a polyhydroxy compound to a reaction mixture further containing a lignin-derived monomer and an isocyanate, the resulting polyurethane can have thermosetting properties. Therefore, the present invention aims to provide a thermosetting polyurethane comprising a reaction product of a composition comprising (a) depolymerized lignin containing one or more lignin-derived monomers according to any one of formula (I), formula (Ia), or formula (Ib), (b) an isocyanate, (c) optionally one or more polyhydroxy compounds, and (d) one or more additives as needed. In the synthesis of such a thermosetting polyurethane, the polyhydroxy compound is particularly a polyol having an OH functional value greater than two, i.e., an OH functional value greater than two. In the synthesis of such a thermosetting polyurethane, the polyhydroxy compound is preferably selected from polyether polyols, polyester polyols, polyacrylic polyols, polycarbonate polyols, polysiloxane polyols, or mixtures thereof, and these polyols have a molecular weight of 200 to 8000. In the synthesis of such thermosetting polyurethanes, the ratio of NCO to active hydrogen is preferably in the range of 4 to 0.75, more preferably 2 to 0.95, and most preferably 1.5 to 0.75.

[0028] By controlling the crosslinking ability of the reagents used in the synthesis of polyurethanes from lignin-derived monomers as defined herein, the resulting polyurethanes may be either thermosetting or thermoplastic. Similar to thermosetting materials, the synthesis of thermoplastic polyurethanes may also include further reagents, such as polyhydroxy compounds and / or further additives. However, instead of polyhydroxy compounds having an OH functional value greater than 2, polyhydroxy compounds with an OH functional value equal to 2 are used, particularly those selected from polyols, polyether polyols, polyester polyols, polyacrylic polyols, polycarbonate polyols, polysiloxane polyols, or mixtures thereof, having molecular weights of 200 to 8000. Accordingly, in one embodiment, the present invention provides a thermoplastic polyurethane comprising a reaction product of a composition comprising (a) depolymerized lignin containing a lignin-derived monomer according to any one of formula (I), formula (Ia), or formula (Ib), (b) an isocyanate, (c) one or more polyhydroxy compounds, and (d) additives as optional, wherein one or more polyhydroxy compounds are, in particular, polyhydroxy compounds having an OH functional value equal to 2, selected from polyether polyols, polyester polyols, polyacrylic polyols, polycarbonate polyols, polysiloxane polyols, or mixtures thereof, having a molecular weight of 200 to 8000.

[0029] In the synthesis of thermoplastic polyurethane according to the present invention, the reagent may further include an additional chain extender selected from the group consisting of diols, diamines, and combinations thereof, where the diol or diamine is a compound having 2 to 12 carbon atoms. In the synthesis of thermoplastic polyurethane provided herein, the NCO:active hydrogen ratio is preferably in the range of 1 to 0.2, more preferably 1 to 0.5, and most preferably 0.9 to 0.4.

[0030] In the synthesis of polyurethane according to the present invention, the reaction mixture may further include a catalyst, particularly one or more tertiary amines, such as, without limitation, triethylamine, triethylenediamine, dimethylcyclohexylamine, N-methylmorpholine, N-ethylmorpholine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetraethylethylenediamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N,N'-dimethylpiperazine, N,N,N',N'-tetramethylguanidine, N,N,N',N'-tetramethyl-1,3-butanediamine, 2-(dimethylaminoethoxy)ethanol, diazabicyclo[2.2.2]octane, and mixtures thereof.

[0031] In the case where the reaction mixture contains a polyhydroxy compound as described above, the molar ratio of the polyol in the reaction mixture to any one of the lignin-derived monomers of formula (I), formula (Ia), or formula (Ib) is preferably in the range of 10:100 to 90:10, preferably 0.5:95 to 80:20, and more preferably 10:90 to 70:30.

[0032] Depending on the lignin-based material, one, some, or all of the components forming the polyurethane (PU) according to the present invention can be bio-based or are bio-based. The polyurethanes described herein can be obtained by reactive extrusion, batch processing, solution polymerization, reactive injection molding, and cast polymerization, and can be used in a variety of applications, mainly as a substitute for petroleum-based thermoplastic polyurethanes. [Modes for carrying out the invention]

[0033] The polyurethane of the present invention contains lignin-derived monomers, generally referred to as lignin-derived monomers according to one of formulas (I), (Ia), or (Ib), or products obtained by the functionalization of each thereof. In the present invention, the above lignin-derived monomers function as short-chain diols (also called chain extenders) or chain arresters. The lignin-derived monomers according to the present invention act as chain extenders (particularly 4-hydroxyalkylphenol (Ia) or its derivative product, functionalized 4-hydroxyalkylphenol (Ib)) or chain arresters (particularly 4-alkylphenol (Ia) or its derivative product, functionalized 4-alkylphenol (Ib)), while other components of the depolymerized lignin oil (dimers, trimers, and oligomers) act as crosslinking agents. The ratio of chain extenders (monomers) to crosslinking agents (dimers, trimers, and oligomers) contained in the polyurethane determines the properties of the polyurethane, i.e., whether the polyurethane is thermoplastic or thermosetting. The polyurethane comprises a reaction product of a composition containing a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib) with an isocyanate. A particular object of the present invention is to provide the synthesis of a lignin-derived thermosetting polyurethane, which comprises a reaction product of an isocyanate with a composition containing a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib), as well as lignin-derived dimers, trimers, and oligomers.

[0034] Accordingly, in a first embodiment, the present invention provides a polyurethane comprising a reaction product of a composition comprising a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib) and an isocyanate. In another embodiment, the present invention provides a method for synthesizing a polyurethane, comprising reacting a composition comprising a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib) with an isocyanate.

[0035] A composition containing lignin-derived monomers can be, for example, a depolymerized lignin oil containing lignin-derived dimers, trimers, and oligomers. In this case, for use in the synthesis of thermosetting polyurethanes, such oil contains at least 10% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib). Thus, in another embodiment, the present invention provides a thermosetting polyurethane comprising a reaction product of an isocyanate composition and a depolymerized lignin oil composition containing at least 10% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib). In one embodiment, the present invention provides a method for synthesizing a thermosetting polyurethane, comprising reacting a depolymerized lignin oil containing at least 10% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib) with an isocyanate.

[0036] Compositions containing lignin-derived monomers, dimers, trimers, and oligomers can be used in the synthesis of thermoplastic polyurethanes. In this case, it is necessary to adjust the NCO / OH ratio so that the equivalent amount of NCO is lower than the equivalent amount of OH to prevent crosslinking.

[0037] Without departing from a depolymerized lignin oil containing a conventional amount of lignin-derived monomers according to formula I obtained from the depolymerization of lignin, a concentrated fraction containing up to 90% by weight, particularly about 50% to a maximum of about 90% by weight, and more particularly about 70% to about 90% by weight, of any one of the lignin-derived monomers of formula (I), formula (Ia), or formula (Ib) can be used. In a second embodiment, the present invention provides a polyurethane comprising a reaction product of a composition containing up to 90% by weight of a lignin-derived monomer according to any one of formula (I), formula (Ia), or formula (Ib) with an isocyanate. In another embodiment, the present invention provides a method for synthesizing a polyurethane, comprising reacting a composition containing up to 90% by weight, particularly about 50% to a maximum of about 90% by weight, and more particularly about 70% to about 90% by weight, of a lignin-derived monomer according to any one of formula (I), formula (Ia), or formula (Ib) with an isocyanate. As previously stated herein, by using these concentrated fractions separately, crosslinking can be reduced, and the resulting polyurethane exhibits more elastomer / rubber-like behavior.

[0038] In each of the embodiments described above, further reagents may be used in the polyurethane synthesis according to the present invention. Such further reagents include chain extenders (short-chain diols, diamines, or combinations thereof), polyols, one or more additives, and catalysts. Among these further reagents, the polyols include long-chain diols, also known as polymeric diols in the field of polyurethane synthesis.

[0039] In one embodiment, the polyurethane according to the present invention comprises a reaction product of a composition comprising (a) a depolymerized lignin oil containing a lignin-derived monomer according to any one of formula (I), formula (Ia), or formula (Ib); (b) an isocyanate; (c) an additive; (d) optionally a polyol; (e) optionally a chain extender; and (f) optionally an additive. The ratio of polyol to depolymerized lignin is not important to the present invention, but is preferably in the range of 0% by weight:100% by weight to 90% by weight:10% by weight, more preferably 0.5% by weight:95% by weight to 80% by weight:20% by weight, and most preferably 10% by weight:90% by weight to 70% by weight:30% by weight. Another embodiment of the present invention provides a method for synthesizing polyurethane, comprising reacting an isocyanate with a composition comprising (a) a depolymerized lignin oil containing a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib), (b) optionally a polyol, (c) optionally a chain extender, and (d) optionally an additive. The ratio of polyol to depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10% by weight, more preferably 0.5% by weight:95% by weight to 80% by weight:20% by weight, and most preferably 10% by weight:90% by weight to 70% by weight:30% by weight. By using such a depolymerized lignin oil, which also contains lignin-derived dimers, trimers, and oligomers in addition to the lignin-derived monomer, a thermosetting polyurethane is typically provided. The greater the amount of lignin-derived monomers from formula (I), formula (Ia), or formula (Ib), the less likely crosslinking is to occur, and the more thermoplastic the resulting polyurethane becomes.

[0040] A thermosetting polyurethane is provided by using an unconcentrated depolymerized lignin oil containing at least 10% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib).

[0041] Accordingly, in a third embodiment, the present invention provides a thermosetting polyurethane comprising a reaction product of a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight, particularly up to about 50% by weight, and more particularly up to about 70% by weight, of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib); (b) an isocyanate; (c) optionally a polyol; (d) optionally a chain extender; and (e) optionally an additive. The ratio of polyol to depolymerized lignin is not important to the present invention, but is preferably in the range of 0% by weight:100% by weight to 90% by weight:10%, more preferably 0.5% by weight:95% by weight to 80% by weight:20%, and most preferably 10% by weight:90% by weight to 70% by weight:30%. Similar to the method for synthesizing polyurethane described above, this method involves reacting an isocyanate with a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight, particularly up to about 50% by weight, and more particularly up to about 70% by weight, of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib); (b) optionally a polyol; (c) optionally a chain extender; and (d) optionally an additive. The weight ratio of the polyol to the depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10%, more preferably 0.5% by weight:95% by weight to 80% by weight:20%, and most preferably 10% by weight:90% by weight to 70% by weight:30%.

[0042] In further embodiments, the present invention provides a polyurethane comprising a reaction product of a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight and up to 90% by weight of a lignin-derived monomer according to any one of formula (I), formula (Ia), or formula (Ib); (b) an isocyanate; (c) optionally a polyol; (d) optionally a chain extender; and (e) optionally an additive. The ratio of polyol to depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10% by weight, more preferably 0.5% by weight:95% by weight to 80% by weight:20% by weight, and most preferably 10% by weight:90% by weight to 70% by weight:30% by weight. Similar to methods for synthesizing polyurethanes, this method involves reacting an isocyanate with a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight and up to about 90% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib); (b) optionally a polyol; (c) optionally a chain extender; and (d) optionally an additive. The ratio of polyol to depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10%, more preferably 0.5% by weight:95% by weight to 80% by weight:20%, and most preferably 10% by weight:90% by weight to 70% by weight:30%.

[0043] In another embodiment, the present invention provides a thermosetting polyurethane comprising a reaction product of a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight and up to 90% by weight of a lignin-derived monomer according to any one of formula (I), formula (Ia), or formula (Ib); (b) an isocyanate; (c) optionally a polyol; (d) optionally a chain extender; and (e) optionally an additive. The ratio of polyol to depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10%, more preferably 0.5% by weight:95% by weight to 80% by weight:20%, and most preferably 10% by weight:90% by weight to 70% by weight:30%. Similar to methods for synthesizing polyurethanes, this method involves reacting an isocyanate with a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight and up to 90% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib); (b) optionally a polyol; (c) optionally a chain extender; and (d) optionally an additive. The ratio of polyol to depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10%, more preferably 0.5% by weight:95% by weight to 80% by weight:20%, and most preferably 10% by weight:90% by weight to 70% by weight:30%. The ratio of NCO:active hydrogen is preferably in the range of 4 to 0.75, more preferably 2 to 0.95, and most preferably 1.5 to 0.75.

[0044] In another embodiment, the present invention provides a thermoplastic polyurethane comprising a reaction product of a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight and up to 90% by weight of a lignin-derived monomer according to any one of formula (I), formula (Ia), or formula (Ib); (b) an isocyanate; (c) optionally a polyol; (d) optionally a chain extender; and (e) optionally an additive. The ratio of polyol to depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10% by weight, more preferably 0.5% by weight:95% by weight to 80% by weight:20% by weight, and most preferably 10% by weight:90% by weight to 70% by weight:30% by weight. Similar to methods for synthesizing polyurethanes, this method involves reacting an isocyanate with a composition comprising (a) a depolymerized lignin oil containing at least 10% by weight and up to 90% by weight of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib); (b) optionally a polyol; (c) optionally a chain extender; and (d) optionally an additive. The ratio of polyol to depolymerized lignin is preferably in the range of 0% by weight:100% by weight to 90% by weight:10%, more preferably 0.5% by weight:95% by weight to 80% by weight:20%, and most preferably 10% by weight:90% by weight to 70% by weight:30%. The ratio of NCO:active hydrogen is preferably in the range of 1 to 0.2, more preferably 1 to 0.5, and most preferably 0.9 to 0.4.

[0045] In each of the embodiments described above, the chemical and physical properties of TPU can be fine-tuned by varying the types and ratios of various reagents. The TPU can be synthesized using conventional processing equipment, catalysts, and processes. In this process, various components can be bio-based.

[0046] Isocyanate composition In one embodiment, the isocyanate suitable for synthesizing the polyurethane according to the present invention may be any of the isocyanates previously disclosed as suitable for the preparation of polyurethanes, and includes aliphatic diisocyanates, aromatic diisocyanates, alicyclic diisocyanates, and mixtures thereof.

[0047] Examples of diisocyanates include methylenebis(phenylisocyanate), 2,4-toluenediisocyanate and 2,6-toluenediisocyanate, including 4,4'-isomers, 2,4'-isomers and mixtures thereof, m-phenylenediisocyanate and p-phenylenediisocyanate, chlorophenylenediisocyanate, a,a'-xylylenediisocyanate, o-tolidinediisocyanate, and 1,5-naphthylene. Examples include, but are not limited to, methylenebis(cyclohexyl isocyanates), cyclohexylenebis(1,2-, 1,3- or 1,4-, and mixtures thereof), which include tallen diisocyanate, hexamethylene-1,6-diisocyanate, pentamethylene-1,5-diisocyanate, 1,4-butane diisocyanate, isophorone diisocyanate, 4,4'-isomers, 2,4'-isomers, and mixtures thereof. Modified forms of methylenebis(phenyl isocyanate) that can be stable liquids at ambient temperature are also examples. The dimers and trimers of the above-mentioned diisocyanates can also be used in polyurethane synthesis.

[0048] More preferably, the diisocyanate is selected from methylenebis(phenyl isocyanate) containing 4,4'-isomers, 2,4'-isomers, and mixtures thereof, 2,4-toluene diisocyanate and 2,6-toluene diisocyanate, and mixtures thereof, hexamethylene-1,6-diisocyanate, pentamethylene-1,5-diisocyanate, 4,4'-isomers, 2,4'-isomers, and mixtures thereof, methylenebis(cyclohexyl isocyanate).

[0049] The ratio of the total equivalent of all diisocyanates to the total equivalent of the active hydrogen-containing components (lignin-derived monomers, any further short-chain diol chain extenders and any long-chain polyols, and any crosslinking agents (see below)), along with the monomer content and type, determines the class of the resulting polymer. For thermosetting polymers, the NCO:active hydrogen ratio is preferably in the range of 4 to 0.25, more preferably 2 to 0.5, and most preferably 1.5 to 0.75. For thermoplastic polymers, the NCO:active hydrogen ratio is preferably in the range of 2 to 0.2, more preferably 1 to 0.3, and most preferably 0.9 to 0.4.

[0050] A composition comprising a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib). The object of the present invention is to provide a bio-based source of components in polyurethane synthesis, and a composition comprising a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib) is typically based on depolymerized lignin oil. It is clear that the overall composition of monomers in depolymerized lignin depends on the type of lignocellulose selected as the starting material, as well as the depolymerization conditions and reaction. Several types of depolymerization methods, particularly reductive catalytic methods, can yield 4-hydroxylalkylphenol and / or 4-alkylphenol in good yield (up to 50% by weight). The selectivity for 4-hydroxylalkylphenol or 4-alkylphenol depends on the depolymerization conditions, for example, the type of catalyst used for depolymerization. Typically, 4-hydroxylalkylphenol and / or 4-alkylphenol are located at position R 1 , R 2 , R 3 and R 4 It is obtained as a mixture of monomers (formula Ia) in which each of the following changes independently. The most common monomer is R 1 and R 2 H is R 3 OCH3 is R 4A 4-hydroxylalkylphenol and / or 4-alkylphenol monomer (formula Ia) is H or OCH3, n is 3, and R is OH or CH3. A mixture of such monomers can be used in the protocol described, so R 1 and R 2 Each is independently H or CH3, and R 3 and R 4 It can be described independently as H or OCH3. In addition to monomers, depolymerization of lignin yields higher molecular weight molecules (dimers, trimers, and oligomers). A depolymerized lignin oil containing at least 10% of 4-hydroxylalkylphenol and / or 4-alkylphenol monomer (formula Ia) can be used in polyurethane synthesis. The dimers, trimers, and oligomers act as branching components, resulting in branched or partially crosslinked polymers.

[0051] Surprisingly, polyurethanes obtained from depolymerized lignin oligomers were found to have completely different properties from lignin-based polyurethanes made from industrial lignin (Kraft Lignin). Kraft Lignin has a higher molecular weight, higher polydispersity, and lower functional value than lignin oil (fewer aliphatic OH groups, fewer uncondensed aromatics, and more condensed aromatics) (Table 1). While depolymerized lignin oil is a fluid liquid, Kraft Lignin is a powder, requiring DMF to produce polyurethane (Ind. Crop. Prod. 2019, 141, 111655). Kraft Lignin has low solubility in common polyols, so a solvent is required to incorporate it. Depolymerized lignin oil has higher miscibility with common polyols used in polyurethane synthesis, such as polypropylene glycol or polytetrahydrofuran. The properties of depolymerized lignin oil provide advantages in polyurethane manufacturing and product characteristics.

[0052] The greatest advantage of using depolymerized lignin is that it allows for a higher percentage of polyol substitution. Using Kraft lignin, it is difficult to produce polyurethane with more than 30% polyol substitution (Ind. Crop. Prod. 2019, 141, 111655 and its references). In contrast, using depolymerized lignin allows for even complete polyol substitution. This results in a stiffer material, as indicated by the storage modulus (Table 3). The mechanical properties are better than those of polyurethane produced from Kraft lignin (Ind. Crop. Prod. 2019, 141, 111655).

[0053] Furthermore, uniformity is better both during resin production and during the production of the final product. (Solvent extraction) When Kraft lignin is used, particles typically form, which need to be filtered. Whether the uniformity of the final product is good can be determined by the peak full width at half maximum.

[0054] Because depolymerized lignin oil has better miscibility, it can be used with a wider range of solvents (dichloromethane, ethyl acetate, methanol, ethanol, butanol, acetone, ethyl methyl ketone) than Kraft lignin, which is soluble only in tetrahydrofuran, dimethylformamide, and dimethyl sulfoxide. Furthermore, because depolymerized lignin oil has better compatibility with other components of a formulation, it is possible to use less solvent or even avoid solvent use altogether.

[0055] Finally, as shown in Table 3, a very wide range of properties can be obtained by adjusting the lignin content, lignin type, polyol, isocyanate, and NCO / OH ratio.

[0056] Depolymerization of lignin oil yields a lighter-colored polyurethane material than when using (solvent-extracted) Kraft lignin with the same lignin content (Figure 1A). The transparency of the material synthesized from depolymerized lignin oil is higher than that of the material made from (solvent-extracted) kraft lignin (Figure 1B).

[0057] The entire depolymerized lignin oil and monomers extracted from the depolymerized lignin oil can be functionalized to convert the phenolic hydroxyl group (formula Ia) of 4-hydroxylalkylphenol and / or 4-alkylphenol to an aliphatic hydroxyl group (formula Ib). This reaction can be carried out using a variety of chemicals, for example, non-limitedly, cyclic ethers such as ethylene oxide, propylene oxide, butylene oxide, tetrahydrofuran, 5-methyltetrahydrofuran, etc.; cyclic carbonates such as ethylene carbonate and propylene carbonate, etc.; and haloalcohols such as 2-chloroethanol, 2-iodoethanol, 3-chloro-1-propanol, 3-bromo-1-propanol, and 4-chlorobutanol, 5-bromo-1-pentanol, 6-chlorohexanol, 8-chloro-1-octanol, 10-chloro-1-decanol, etc.

[0058] Selective functionalization of phenolic hydroxyl groups can be achieved in various ways. One option is to use a base that deprotonates phenolic hydroxyls but not aliphatic hydroxyls. Examples of common bases that satisfy this criterion include ammonia and metal hydroxides M(OH) x Preferably alkali metal hydroxides (e.g., NaOH or KOH), formula M x (CO3) y Examples include, but are not limited to, carbonates containing (e.g., Na2CO3 or K2CO3).

[0059] Modifying the 4-hydroxyalkylphenol and / or 4-alkylphenol of formula Ia according to the procedure described above yields the functionalized 4-hydroxyalkylphenol and / or 4-alkylphenol monomer of formula Ib.

[0060] [ka] 4-Hydroxyalkylphenol (R=OH) 4-alkylphenol (R=CH3) Equation Ia [ka] Functionalized 4-hydroxyalkylphenol (R=OH) Functionalized 4-alkylphenol (R=CH3) Formula Ib (In the formula, R represents OH or CH3, R 1 and R 2 These are independently H or alkyl, particularly H or C 1-6 Alkyl, and more particularly H or CH3, R 3 and R 4 These are independently H or oxyalkyl, particularly H or oxyC 1-6 Alkyl, and more specifically H or OCH3, n is between 0 and 3. m is between 1 and 12.

[0061] In one embodiment, lignin-derived monomers can be converted to amino alcohols or diamines. These can also be used as chain extenders in PU synthesis.

[0062] Preferably, the polyhydroxy compound includes a polymeric polyol compound having a molecular weight of 200 to 10,000, as detailed below. The molar ratio of the polyol to any one of the lignin-derived monomers of formula (I), formula (Ia), or formula (Ib) is preferably in the range of 0:100 to 90:10, more preferably 0:5:95 to 70:30, and most preferably 10:90 to 70:30. Therefore, in a preferred embodiment, the present invention provides a thermosetting polyurethane obtained by the reaction of a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib), an isocyanate, one or more polyhydroxy compounds, and at least one trihydroxy compound acting as a crosslinking agent, wherein the molar ratio of the polyol to the lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib) is in the range of 10:100 to 90:10, preferably 0.5:95 to 70:30, and more preferably 10:90 to 70:30.

[0063] Additional chain extenders In each of the embodiments described above, when a depolymerized lignin oil containing a lignin-derived monomer according to any one of formulas (I), (Ia), or (Ib), or a lignin-derived monomer of formula (I), (Ia), or (Ib), is used in PU synthesis, additional chain extenders, particularly short-chain extenders, may be added. The chain extenders are preferably for formulations targeting thermoplastic polyurethanes, in which the short-chain extenders form a rigid phase and the polyol forms a flexible phase. In such cases, the molar ratio of the (functionalized) lignin-derived monomer to the additional chain extender can be 99:1 to 1:99, preferably 90:10 to 10:90, and most preferably 80:20 to 20:80. The additional chain extenders include diols, diamines, and combinations thereof, having 2 to 12 carbon atoms.

[0064] Examples of chain extenders include, but are not limited to, ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,4-butanediol, 1,6-hexanediol, 1,3-butanediol, 1,5-pentanediol, neopentyl glycol, 2-ethyl-2-butyl-1,3-propanediol, 1,4-cyclohexanedimethanol, hexamethylenediol, heptanediol, nonanediol, dodecanediol, benzenedimethanol (1,2-, 1,3- or 1,4-, and mixtures thereof), bis(2-hydroxyethoxy)benzene (1,2-, 1,3- or 1,4-, and mixtures thereof), ethylenediamine, butanediamine, 1,2-propylenediamine, 1,6-hexamethylenediamine, piperazine, ethanolamine, N-methyl-diethanolamine, N-ethyldiethanolamine, N-phenylpropanolamine, and mixtures thereof.

[0065] polyol In each of the embodiments described above, the polyol may be any from the categories of polyether polyols, polyester polyols, polyacrylic polyols, polycarbonate polyols, or polysiloxane polyols, or mixtures thereof, preferably having a molecular weight of 200 to 8000, more preferably 300 to 6000, and most preferably 400 to 4000. In the case of thermosetting polyurethanes, the polyol is a major component together with the isocyanate. The polyol is completely or partially replaced by depolymerization lignin oil. In the case of thermoplastic polyurethanes, there are two diols, namely short-chain diols (also called chain extenders) and long-chain diols (called polyols in TPU production).

[0066] In one embodiment, the polyol may include a polyether polyol. Suitable polyether polyols may include polyether polyols derived from diols or polyols reacted with ethers containing alkylene oxides, typically ethylene oxide, propylene oxide, butylene oxide, amylene oxide, or mixtures thereof. Suitable initiators for the synthesis of polyether polyols include ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, glycol, 1,6-hexanediol, trimethylolpropane, 1,2,6-hexanetriol, glycerin, sucrose, sorbitol, pentaerythritol, ethanolamine, toluenediamine, and Mannich bases. Examples of usable polyether polyols include, but are not limited to, poly(ethylene glycol), poly(propylene glycol), and poly(tetramethylene ether glycol), also known as polytetrahydrofuran. Suitable polyether polyols include polyetheramines, particularly diamines and polyamide adducts, such as reaction products of ethylenediamine or triethanolamine with propylene oxide. Copolyethers obtained from the reaction of tetrahydrofuran with ethylene oxide or propylene oxide can also be used in the present invention. Polyether compositions may include mixtures of polyethers.

[0067] In one embodiment, the polyol may include a polyester polyol. The polyester polyol is produced by either an esterification reaction of one or more glycols with one or more dicarboxylic acids or anhydrides, or a transesterification reaction of one or more glycols with esters of dicarboxylic acids. The dicarboxylic acid of the desired polyester may be aliphatic, alicyclic, aromatic, or a combination thereof. Exemplary examples of dicarboxylic acids include, but are not limited to, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, isophthalic acid, terephthalic acid, cyclohexanedicarboxylic acid, and mixtures thereof. Anhydrides of the above-mentioned dicarboxylic acids, such as phthalic anhydride, tetrahydrophthalic anhydride, and mixtures thereof may also be used. The glycol that reacts to form the desired polyester intermediate may be aliphatic, aromatic, or a combination thereof, and may include any of the glycols described in the section on chain extenders above. Examples include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, decamethylene glycol, dodecamethylene glycol, 1,1,1-trimethylolpropane, 1,1,1-trimethylolethane, 1,2,6-hexanetriol, α-methyl glucoside, pentaerythritol, sorbitol, and mixtures thereof.

[0068] In one embodiment, the polyol may include a polyacrylic polyol.

[0069] In one embodiment, the polyol may include a polycarbonate polyol. A polycarbonate polyol can be produced by reacting a diaryl carbonate with a diol, such as propylene glycol, 1,4-butanediol, or 1,6-hexendiol, or a mixture thereof.

[0070] In one embodiment, the polyol may include a polysiloxane polyol. Polysiloxane polyols can be produced by a dehydrogenation reaction of a hydrogenated polysiloxane with an aliphatic polyhydric alcohol or a polyoxyalkylene alcohol. Exemplary examples include α-ω-hydroxypropyl-terminated poly(dimethylsiloxane), α-ω-aminopropyl-terminated poly(dimethylsiloxane), and copolymers of poly(dimethylsiloxane) material and poly(alkylene oxide).

[0071] Crosslinking agent As described above, the crosslinking agents used in the synthesis of thermosetting polyurethanes typically consist of polyols (e.g., trihydroxy compounds) with a higher functional value, i.e., a higher functional value than diols. Such high functional groups are already present when depolymerizing lignin oil is used in the synthesis of lignin-derived PU. Furthermore, in these embodiments as well, if the requirement for crosslinking in the final product is higher, additional crosslinking agents can be employed. In particular, such crosslinking agents are low molecular weight, highly functional hydroxyl and amine-terminated compounds, and more particularly, low molecular weight, highly functional hydroxyl-terminated compounds, such as glycerol, trimethylolpropane, 1,2,6-hexanetriol, and pentaerythritol.

[0072] catalyst A catalyst to facilitate the reaction between the isocyanate group and the isocyanate-reactive group (hydroxyl or amine) is not essential but can be used. The following two types of catalysts can be used independently: Tertiary amines, for example, non-limitingly, triethylamine, triethylenediamine, dimethylcyclohexylamine, N-methylmorpholine, N-ethylmorpholine, N,N,N',N'-tetramethylethylenediamine, N,N,N',N'-tetraethylethylenediamine, N,N-dimethylethanolamine, N,N-diethylethanolamine, N,N'-dimethylpiperazine, N,N,N',N'-tetramethylguanidine, N,N,N',N'-tetramethyl-1,3-butanediamine, 2-(dimethylaminoethoxy)ethanol, diazabicyclo[2.2.2]octane, and mixtures thereof. Organometallic compounds, such as, without limitation, stannous octanoate, stannous oleate, lead octanoate, dibutyltin dioctanoate, dibutyltin dilaurate, dibutyltin diacetate, iron(III) acetylacetone, magnesium acetylacetone, bismuth neodecanoate, and mixtures thereof. The amount of catalyst used is usually in the range of 0.0001% to 1.0% by weight of the total weight of the reactants.

[0073] additives In addition to catalysts, conventional auxiliary agents and additives can also be added to the components, reaction mixture, or after polyurethane production. Examples of these include, but are not limited to, flame retardants, antioxidants, nucleating agents, blowing agents, stabilizers against hydrolysis, light, heat, oxidation or discoloration, surfactants, lubricants and release agents, dyes and pigments, inhibitors, antimicrobial agents, impact modifiers, rheological modifiers, ultraviolet absorbers, inorganic and / or organic fillers, reinforcing agents, and plasticizers. Chain modifiers may be optionally added. These compounds have only one functional group that is reactive with isocyanate.

[0074] Polymerization techniques useful for producing the polyurethane of the present invention include conventional methods such as foam production, molding, extrusion, batch processing, solution polymerization, reaction injection molding, and cast polymerization.

[0075] (Partially) bio-based polyurethanes can be used as a substitute for petroleum-based polyurethanes, for example, not limited to, interiors, automotive suspension bushings, bedding, car and truck seats, straps and bands, elastomer wheels and tires, flexible foams for seats, rigid foams for insulation panels, seals and gaskets for microcellular foams, electric potting compounds, seals, gaskets, carpet underlays, rigid plastic parts, sporting goods, medical devices, mobile electronic devices, laptop keyboard protectors, automotive instrument panels, caster wheels, power tools, footwear, performance films, wire and cable jackets, adhesives and textile coatings, and 3D printing applications. [Brief explanation of the drawing]

[0076] [Figure 1] (Figure 1A) Comparison of the brightness of polyurethane materials using depolymerized lignin oil and (solvent-extracted) Kraft lignin. (Figure 1B) Comparison of the transparency of polyurethane materials using depolymerized lignin oil and (solvent-extracted) Kraft lignin. [Examples]

[0077] Two different depolymerized lignins with varying amounts of dihydroconiferyl alcohol were tested (Lignin 1 and Lignin 2). Lignin 3 and Lignin 4 are model depolymerized lignins prepared by mixing Kraft lignin extracted with ethyl methyl ketone with 20% (Lignin 3) and 30% (Lignin 4) of dihydroconiferyl alcohol (DCA). Lignin 5 is Kraft lignin extracted with ethyl methyl ketone. Lignin 6 is Kraft lignin used as a reference. Characterization of the lignins is provided in Table 1.

[0078] Table 1. Characterization of the lignin used. [Table 1]

[0079] This table shows that the aliphatic OH content is directly related to the amount of DCA.

[0080] Thermosetting polyurethane was synthesized according to a standard protocol. In a dry round-bottom flask, the polyol (if present), lignin, and catalyst were dissolved in dry ethyl methyl ketone. Isocyanate was added to this solution and reacted at 40°C for 1 hour. The solution was filtered and poured into a Teflon® mold. The solvent was slowly evaporated overnight, and the film was cured in a 100°C oven for 7 hours to complete the process.

[0081] The composition of the thermosetting polyurethane is shown in Table 2 below. EcoN7300 is a bio-based pentamethylene diisocyanate. HDI refers to hexamethylene diisocyanate, and HDI trimmer refers to hexamethylene diisocyanate trimmer.

[0082] [Table 2]

[0083] Table 3. Characterization of the fabricated thermosetting polyurethane. [Table 3]

[0084] Drawing translation Figure 1A Lignin wt% (as com. to co-polyol) Lignin Source Solvent-extracted (EMK) Kraft Lignin Depolymerized Lignin Oligomers Darker samples Lighter color with depolymerized lignin. Figure 1B Samples made from Kraft lignin always tend to be more hazy. Better transparency with depolymerized lignin.

Claims

1. A method for producing thermoplastic polyurethane, (a) Equation (I) 【Chemistry 1】 (In the formula, R is either OH or CH 3 This represents, R 1 and R 2 represents H or alkyl independently, R 3 and R 4 This independently represents H or oxyalkyl, R 5 represents H or hydroxyalkyl, n is between 0 and 3. Equation (Ia) 【Chemistry 2】 (In the formula, R is either OH or CH 3 This represents, R 1 and R 2 each independently represents H or alkyl, R 3 and R 4 This independently represents H or oxyalkyl, n is between 0 and 3), or Formula (Ib) 【Transformation 3】 (In the formula, R is either OH or CH 3 This represents, R 1 and R 2 represents H or alkyl independently, R 3 and R 4 This independently represents H or oxyalkyl, n is between 0 and 3. m is between 1 and 12. A depolymerized lignin oil containing at least 10% by weight and up to 90% by weight of lignin-derived monomers from any one of the following, (b) A reaction product characterized by reacting a composition containing an isocyanate, NCO: Produced by adjusting the ratio of active hydrogen to be in the range of 1-0.2, 1-0.5, or 0.9-0.

4. A method for manufacturing thermoplastic polyurethane.

2. The method for producing a thermoplastic polyurethane according to claim 1, wherein the composition further comprises (c) one or more polyhydroxy compounds, (d) a chain extender, and / or (e) an additive.

3. The method for producing a thermoplastic polyurethane according to claim 2, wherein the one or more polyhydroxy compounds include a polyol having a functional value of 2 or more.

4. A method for producing a thermoplastic polyurethane according to claim 3, comprising a polyhydroxy compound selected from polyols, polyether polyols, polyester polyols, polyacrylic polyols, polycarbonate polyols, polysiloxane polyols, or mixtures thereof, having a molecular weight of 200 to 8000.

5. The method for producing a thermoplastic polyurethane according to claim 1, wherein the composition further comprises an additional chain extender selected from the group consisting of diols, diamines, or combinations thereof, wherein the diol and the diamine have 2 to 12 carbon atoms.

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