Method for producing a BIO-based polyol

Abstract

The present disclosure provides a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1:13 or greater.

Description

METHOD FOR PRODUCING A BIO-BASED POLYOLFIELD OF INVENTION

[0001] The present disclosure relates to a method of preparing a bio-based polyol and a bio-based polyol obtainable by the method. The present disclosure also relates to a method of preparing a polyurethane foam using the bio-based polyol, a polyurethane foam obtainable by the method, and an article (such as an automotive seat) comprising the polyurethane foam. The bio-based polyol of the present disclosure has a high bio-content, and consequently so does the polyurethane foam prepared using the bio-based polyol. Moreover, use of the bio-based polyol in preparing a polyurethane foam yields excellent mechanical properties of the foam, such as a low Tan delta (which is required for a high resilience foam).BACKGROUND

[0002] Polyols find many uses in chemistry. One important use is in the preparation of polyurethanes, such as flexible polyurethane foams. Polyurethanes are prepared by reacting polyisocyanates with polyols.

[0003] However, currently, the vast majority of polyols used in polyurethanes are derived from non-bio (or non-renewable) resources, e.g., petroleum-based resources. The non-bio resources are finite, their price may fluctuate, and their use may adversely affect the environment. Thus, there is a growing demand and need for polyols derived from bio (or renewable) resources, termed herein “bio-based polyols”. An example of a bio resource is a vegetable oil.

[0004] In order to be commercially useful, bio-based polyols need to have the requisite properties in order to replace petroleum-based polyols to ensure good properties of the polyurethanes. For example, in flexible polyurethane foams, the polyol(s) used in its preparation should contribute to a low Tan delta of the flexible foam.

[0005] The current state-of-the-art bio-based polyols generally have a low bio-content and / or do not have the requisite properties in order to replace petroleum-based polyols in certain polyurethane applications. Even when a bio-based polyol may replace a petroleum-based polyol in the preparation of a polyurethane, it is often the case that only a small proportion of the petroleumbased polyol may be replaced with the bio-based polyol. This is due to a deterioration of the properties of the polyurethane when a large proportion of the petroleum-based polyol is replaced with the bio-based polyol. Moreover, the current methods of making the bio-based polyols may be complicated, and a simplified method is desired.

[0006] Thus, there is a need for a simple method of preparing a bio-based polyol which yields a biobased polyol having a high bio-content and the requisite properties in order to replace petroleumbased polyols in certain polyurethane applications. It is particularly desired that the bio-based polyol can replace all, or most of, the petroleum-based polyol in the preparation of polyurethanes, so as to increase the bio-content of the polyurethane.

[0007] The present disclosure addresses the problems and needs mentioned above.SUMMARY

[0008] In a first aspect, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the biobased polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 13 or greater.

[0009] The method of the present disclosure allows for a high bio-content in the bio-based polyol, owing to the use of a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof in a molar ratio (of the initiator to the fatty acid component) of from 1: 13 or greater. That is, a large amount of bio-derived hydroxyl-containing fatty acid or ester thereof is used per initiator molecule, such that the average bio-content in the resulting bio-based polyol is high. This is also made possible by the use of an initiator comprising at least three hydroxyl groups, which ensures the initiator has a functionality of 3 or more, meaning that there are ample hydroxyl groups in the initiator to react with the bio-derived hydroxyl-containing fatty acid or ester thereof.

[0010] Moreover, the inventors have surprisingly found that the bio-based polyols prepared according to the method of the present disclosure allow for the preparation of polyurethanes having excellent mechanical properties, such as low Tan delta.

[0011] In a second aspect, there is provided a bio-based polyol obtainable by the method according to the present disclosure.

[0012] In a third aspect, there is provided a method of preparing a polyurethane foam, the method comprising: providing an isocyanate-reactive component comprising the bio-based polyol as defined herein; providing an isocyanate component comprising a polyisocyanate; and reacting the isocyanate-reactive component and isocyanate component, in the presence of a blowing agent, to obtain the polyurethane foam.

[0013] In a fourth aspect, there is provided a polyurethane foam obtainable by the method described herein.

[0014] In a fifth aspect, there is provided an automotive seat, automotive under-carpet, automotive dash insulator, or mattress comprising the foam described herein.

[0015] The embodiments described should not be read to limit or otherwise narrow the scope of any inventive concepts otherwise provided by the present disclosure. While multiple embodiments are disclosed, other embodiments will become apparent to those skilled in the art from the following description. Accordingly, the description is to be regarded as illustrative rather than restrictive.DETAILED DESCRIPTION

[0016] There is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 13 or greater. The molar ratio “1: 13 or greater” means that there is a minimum of 13 moles of fatty acid component per 1 mole of initiator, and there may be more than 13 moles of fatty acid component per 1 mole of initiator, such as 30 moles of fatty acid component per 1 mole of initiator.

[0017] [Fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof]

[0018] The fatty acid component comprises a bio-derived hydroxyl-containing fatty acid or ester thereof. The fatty acid component may comprise one or more different bio-derived hydroxyl-containing fatty acids (or esters thereof), and may further comprise one or more bio-derived fatty acids or esters thereof without hydroxyl group(s). This may be the case when a complex mixture of fatty acids or esters thereof is used as the fatty acid component to prepare the bio-based polyol, wherein a portion of the fatty acid component is bio-derived hydroxyl-containing fatty acids or esters thereof. In one embodiment, the portion of the fatty acid component which is bio-derived hydroxyl-containing fatty acids or esters thereof is 70 weight% or higher, or 80 weight% or higher, or 85 weight% or higher, or 90 weight% or higher, or 95 weight% or higher, or substantially 100 weight%, based upon the total weight of the fatty acid component. In one embodiment, the fatty acid component consists only of bio-derived hydroxyl-containing fatty acids or esters thereof.

[0019] In one embodiment, the hydroxyl-containing fatty acid or ester thereof may contain one or more different hydroxyl-containing fatty acids or esters thereof. Preferably, the hydroxyl-containing fatty acid or ester thereof contains only one type of hydroxyl-containing fatty acid or ester thereof.

[0020] As used herein, the term “fatty acid or ester thereof’ refers to a linear or branched aliphatic carboxylic acid (or ester thereof, or a salt thereof) comprising at least a (linear) hydrocarbon chain (sometimes called the “fatty acid chain”) and a terminal carboxyl group (or ester group, or salt thereof). Fatty acids and esters thereof generally occur naturally in oils and fats.

[0021] In one embodiment, the bio-derived hydroxyl-containing fatty acid or ester thereof comprises at least 8 carbon atoms in total, or at least 9 carbon atoms in total, or at least 10 carbon atoms in total, or at least 11 carbon atoms in total, or at least 12 carbon atoms in total, or at least 13 carbon atoms in total, or at least 14 carbon atoms in total, or from 12 to 30 carbon atoms in total, or from 8 to 28 carbon atoms in total, or from 10 to 26 carbon atoms in total, or from 12 to 25 carbon atoms in total, or from 14 to 24 carbon atoms in total, or from 14 to 23 carbon atoms in total, or from 14 to 22 carbon atoms in total, or from 14 to 21 carbon atoms in total, or from 14to 20 carbon atoms in total, or from 15 to 20 carbon atoms in total, or from 16 to 20 carbon atoms in total, or from 17 to 19 carbon atoms in total, or 18 carbon atoms in total.

[0022] In one embodiment, the bio-derived hydroxyl-containing fatty acid or ester thereof may contain one or more carbon-to-carbon double bonds (an unsaturation) in the hydrocarbon chain. Preferably, the bio-derived hydroxyl-containing fatty acid or ester thereof contains one carbon- to-carbon double bond in the hydrocarbon chain located between the carboxylic acid group (or ester group) and the hydroxyl group.

[0023] The bio-derived hydroxyl-containing fatty acid or ester thereof contains one or more hydroxyl groups. In one embodiment, the bio-derived hydroxyl-containing fatty acid or ester thereof may comprise one hydroxyl group, or two hydroxyl groups, or three hydroxyl groups. Preferably, the bio-derived hydroxyl-containing fatty acid or ester thereof comprises one hydroxyl group.

[0024] In one embodiment, the bio-derived hydroxyl-containing fatty acid or ester thereof does not comprise a hydroxyl group on the first to sixth carbon atom in the (linear) hydrocarbon chain, wherein the first carbon atom is that of the carboxylic acid group (i.e., the carbon of the carbonyl group). This is to avoid cyclisation into a lactone.

[0025] In one embodiment, the hydroxyl group(s) of the fatty acid or ester thereof is a secondary hydroxyl group. As used herein, “secondary hydroxyl” refers to a hydroxy group (-OH) which is bonded to a carbon atom, which itself is bonded to two other carbon atoms and one hydrogen atom.

[0026] Preferred hydroxyl-containing fatty acids (or esters thereof) include hydroxyl-containing omega-9 fatty acids or esters thereof. In one embodiment, the hydroxyl-containing fatty acid or ester thereof is selected from ricinoleic acid, lesquerolic acid, an ester or salt thereof, and a combination thereof. Preferably, the hydroxyl-containing fatty acid or ester thereof is ricinoleic acid, an ester thereof or a salt thereof. The structure of ricinoleic acid is depicted below:

[0027] As used herein, the term “bio-derived hydroxyl-containing fatty acid or ester thereof’ refers to a hydroxyl-containing fatty acid or ester thereof which is derived from bio-resources (i.e., renewable resources). Such bio-resources include naturally occurring compounds, such as vegetable oil. A particularly preferred form of bio-resource from which to derive the hydroxyl- containing fatty acid or ester thereof is castor oil. Ricinoleic acid constitutes about 90% of the fatty acids in castor oil. The bio-resource may require work up and / or chemical reaction(s) to obtain the hydroxyl-containing fatty acid or ester thereof. For instance, the bio-resource may need purifying to obtain the hydroxyl-containing fatty acid or ester thereof in a purified form. Alternatively, the fatty acid obtained from the bio-resource may not contain a hydroxyl group,and this may need to be introduced via a chemical reaction. The skilled person would be aware of the required work up and chemical reaction(s) required to obtain the hydroxyl-containing fatty acid or ester thereof from the bio-resource.

[0028] [Initiator comprising at least 3 hydroxyl groups]

[0029] The initiator comprising at least 3 hydroxyl groups is an organic compound. The hydroxyl groups will react with the carboxylic acids (or ester) of the fatty acids to form esters derived from the initiators and the fatty acids.

[0030] In one embodiment, the initiator may comprise at least 4 hydroxyl groups, or at least 5 hydroxyl groups, or at least 6 hydroxyl groups, or from 3 to 12 hydroxyl groups, or from 4 to 10 hydroxyl groups, or from 4 to 8 hydroxyl groups, or from 5 to 7 hydroxyl groups, or 6 hydroxyl groups.

[0031] In one embodiment, the initiator may have a weight-average molecular weight of below 1000 g / mol, or below 900 g / mol, or below 800 g / mol, or below 700 g / mol, or below 650 g / mol, or below 600 g / mol, or below 550 g / mol, or below 500 g / mol, or below 450 g / mol, or from 150 g / mol to 1000 g / mol, or from 200 g / mol to 800 g / mol, or from 200 g / mol to 700 g / mol, or from 200 g / mol to 600 g / mol, or from 200 g / mol to 500 g / mol, or from 250 g / mol to 450 g / mol, or from 300 g / mol to 450 g / mol. As used herein, the “weight-average molecular weight” may be determined by gel permeation chromatography (GPC). A lower molecular weight for the initiator may translate into a higher bio-content in the bio-based polyol.

[0032] In one embodiment, the initiator may be selected from glycerol, erythritol, threitol, arabitol, xylitol, ribitol, mannitol, sorbitol, galactitol, fucitol, iditol, inositol, volemitol, isomalt, malititol and lactitol.

[0033] In one embodiment, the initiator may be a polyether polyol. The term “polyether polyol” in this context refers to a compound having more than 1 ether functional group (“polyether part”) and more than 1 hydroxyl functional group (“polyol” part). In one embodiment, the polyether polyol may be an alkoxylated polyol. In one embodiment, the poly ether polyol may be an ethoxylated or propoxylated polyol, and may preferably be an ethoxylated polyol. The polyol is preferably a sugar alcohol, which may be selected from glycerol, erythritol, threitol, arabitol, xylitol, ribitol, mannitol, sorbitol, galactitol, fucitol, iditol, inositol, volemitol, isomalt, malititol and lactitol. Most preferably the sugar alcohol is sorbitol. In one embodiment, the initiator is preferably ethoxylated sorbitol or propoxylated sorbitol, and most preferably ethoxylated sorbitol.

[0034] The method of making the alkoxylated polyol may comprise reacting an alkylene oxide with a polyol. The alkylene oxide may be ethylene oxide, propylene oxide or butylene oxide. In one embodiment, 4-8 mole equivalents of alkylene oxide are reacted with 1 mole equivalent polyol. The exact mole ratio of alkylene oxide to polyol may depend on the number of hydroxyl groups in the initiator and the intended degree of alkoxylation. Preferably, 1 equivalent of alkylene oxide is used per 1 hydroxyl group in the initiator. In one embodiment, the ethoxylated sorbitolis prepared by reacting 5 to 7, preferably 6. mole equivalents of ethylene oxide with 1 mole equivalent sorbitol.

[0035] The initiator may be derived from bio resources in order to increase the bio-content of the biobased polyol. Sugar alcohols are derived from sugars, which are naturally occurring.

[0036] The initiator may be a single initiator or a mixture of initiators. That is, the initiator may comprise one or more initiator compounds, such as one or more sugar alcohols.

[0037] [Method of preparing a bio-based polyol]

[0038] The bio-based polyol may be prepared by mixing the initiator with the fatty acid component, in the presence of any catalysts or additives required to react the hydroxyl groups of the initiator with the carboxylic acid groups of the fatty acids (or esters). Typically, the reaction is carried out under an inert atmosphere (e.g., a nitrogen atmosphere).

[0039] The temperature and pressure of the reaction can be varied to achieve desired outcomes. The pressure may be atmospheric pressure or reduced pressure. The temperature is usually from 100 and 220°C, or from 190 to 210°C, or from 195 to 205°C.

[0040] The reaction time may vary depending on the reactants, and the reaction time is as long as required to achieve the required degree of reaction. The reaction may be stopped when the acid value of the polyol is below a certain value, such as below 1.5 mgKOH / g.

[0041] Water and low molecular weight alcohols formed during the reaction may be removed at atmospheric pressure, or at reduced pressure. Further purification of the product mixture may be carried out to obtain a purified bio-based polyol.

[0042] The reactants may be mixed together in one step to obtain the bio-based polyol. Alternatively, the fatty acids or esters thereof may be self-polymerized, and the oligomers obtained therefrom added to an initiator to obtain the bio-based polyol.

[0043] The skilled person would know the conditions required to react the initiator and the fatty acid component in order to obtain the bio-based polyol, and the skilled person would know the purification techniques which would be useful to purify the product polyol.

[0044] An important feature of the method of the present disclosure is the mole ratio of the initiator to the fatty acid component added together at the start of the reaction. In one embodiment, molar ratio of the initiator to the fatty acid component is from 1 : 13 or greater, or from 1 : 13 to 1 : 30, or from 1: 13 to 1:25, or from 1: 13 to 1:20, or from 1: 13 to 1: 19, or from 1: 14 to 1: 19, or from 1: 14 to 1 : 18, or from 1: 15 to l: 18, or from l: 16 to 1: 18. This feature is important to ensure high biocontent in the bio-polyol.

[0045] [Bio-based polyol]

[0046] The bio-based polyol is obtainable by the method described herein.

[0047] In one embodiment, the weight-average molecular weight of the bio-based polyol is at least 2000 g / mol, or at least 2500 g / mol, or at least 3000 g / mol, or at least 3500 g / mol, or at least 4000 g / mol, or from 2000 g / mol to 10,000 g / mol, or from 3000 g / mol to 9000 g / mol, or from 3000g / mol to 8000 g / mol, or from 3500 g / mol to 8000 g / mol, or from 3750 g / mol to 8000 g / mol, or from 4000 g / mol to 8000 g / mol. A high molecular weight of the bio-based polyol is important for the phase separation in a flexible polyurethane foam prepared from the bio-based polyol. This is because the hard blocks and soft blocks (formed from the bio-based polyol) in the polyurethane are then incompatible and therefore generally give good elastic properties in the polyurethane. The weight-average molecular weight may be measured by GPC.

[0048] In one embodiment, the bio-content of the bio-based polyol is at least 50 weight%, or at least 60 weight%, or at least 70 weight%, or at least 80 weight%, or at least 90 weight%, or at least 92.5 weight%, based upon the total weight of the bio-based polyol. A higher bio-content is beneficial in terms of reducing the contribution of petroleum-based / non-renewable resources in the preparation of the polyol.

[0049] The bio-based polyol is a liquid at 25°C. In one embodiment, the viscosity at 25°C of the biobased polyol is below 15 Pa.s, or below 10 Pa.s, or below 9 Pa.s, or below 8 Pa.s, or below 7 Pa.s, or below 6 Pa.s, or below 5 Pa.s, or below 4 Pa.s, or below 3.5 Pa.s, or below 3.25 Pa.s, or below 3 Pa.s, or below 2.75 Pa.s. A suitable lower limit for the viscosity ranges may be 0.1 Pa.s, or 0.5 Pa.s, or 1 Pa.s. A lower viscosity generally means easier processability of the polyol. The viscosity is measured at 25°C with a Brookfield R / S-CPS-P2 Rheometer fitted with C25-2 cone spindle at 350 Pa with a cone and plate geometry (CONE SST 20 mm X 0.5)), and a 50- 150-micron truncation gap.

[0050] In one embodiment, the bio-based polyol has an average OH functionality of at least 2, or at least 2.5, or at least 3, or at least 3.25, or at least 3.5, or from 2 to about 8, or from 2 to about 7, or from 2 to about 6, or from 2 to about 5, or from 2.5 to about 4.5. As used herein, the “average OH functionality” refers to the number average OH functionality, as commonly used in the art. The average OH functionality of a polyol refers to the average number of OH groups in each molecule.

[0051] In one embodiment, the hydroxyl value of the bio-based polyol is from 10 mgKOH / g to 100 mgKOH / g, or from 20 mgKOH / g to 90 mgKOH / g, or from 25 mgKOH / g to 80 mgKOH / g, or from 25 mgKOH / g to 70 mgKOH / g. The hydroxyl value may be determined via potentiometric titration.

[0052] As used herein, the term “bio-based polyol” refers to a polyol derived, at least in part, from bioresources (renewable resources). Such bio-resources include naturally occurring compounds, such as vegetable oils and naturally occurring sugars.

[0053] [A method of preparing a polyurethane foam]

[0054] The present disclosure provides a method of preparing a polyurethane foam, comprising: providing an isocyanate-reactive component comprising the bio-based polyol as described herein; providing an isocyanate component comprising a polyisocyanate; and reacting theisocyanate-reactive component and isocyanate component, in the presence of a blowing agent, to obtain the polyurethane foam.

[0055] Any standard method known in the art may be used to prepare the polyurethane using the biobased polyol. A typical method includes mixing the isocyanate-reactive component and the isocyanate component, in the presence of suitable catalyst(s), surfactant(s) and blowing agent(s), to obtain the polyurethane foam.

[0056] Physical and chemical blowing agents are suitable for use in the present disclosure.

[0057] Any physical blowing agent known in the art can be used as the blowing agent. For example, suitable blowing agent compounds include hydrocarbons, hydrochlorofluorocarbons, hydrofluorocarbons, hydrohaloolefms, or combinations thereof.

[0058] Examples of hydrocarbon blowing agents that may be used include lower aliphatic or cyclic, linear, or branched hydrocarbons (e.g., alkanes, alkenes and cycloalkanes, preferably those compounds having from 4 to 8 carbon atoms). Specific examples of suitable blowing agent compounds include n-butane, iso-butane, 2,3-dimethylbutane, cyclobutane, n-pentane, isopentane, technical grade pentane mixtures, cyclopentane, methylcyclopentane, neopentane, n- hexane, iso-hexane, n-heptane, iso-heptane, cyclohexane, methylcyclohexane, 1 -pentene, 2- methylbutene, 3 -methylbutene, 1 -hexene, or combinations thereof.

[0059] Examples of suitable hydrochlorofluorocarbons include 1 -chloro- 1,2 -difluoroethane, 1- chloro- 2,2-difluoroethane, 1 -chloro- 1 , 1 -difluoroethane, 1 , 1 -dichloro- 1 -fluoroethane, monochlorodifluoromethane, or combinations thereof.

[0060] Examples of suitable hydrofluorocarbons include 1,1,1,2-tetrafluoroethane (HFC 134a), 1, 1,2,2- tetrafluoroethane, trifluoromethane, heptafluoropropane, 1,1,1 -trifluoroethane, 1,1,2- trifluoroethane, 1,1,1,2,2-pentafluoropropane, 1,1,1,3-tetrafluoropropane, 1,1, 1,3,3- pentafluoropropane (HFC 245fa), 1,1,3, 3,3-pentafluoropropane, 1,1,1,3,3-pentafluoro-n- butane (HFC 365mfc), 1,1,1,4,4,4-hexafluoro-n-butane, 1,1,1,2,3,3,3-heptafluoropropane (HFC 227ea), or combinations thereof.

[0061] Examples of suitable hydrohaloolefms are trans-l-chloro-3,3,3-fluoropropene (HFO 1233zd), trans-l,3,3,3-tetrafluoropropene (HFO 1234ze), cis- and trans- l,l,l,4,4,4-hexafluoro-2-butene (HFO 1336mzz), or combinations thereof.

[0062] Chemical blowing agents, such as water, mono-carboxylic acid (e.g., formic acid), and polycarboxylic acid, can also be used as the sole blowing agent. Alternatively, these chemical blowing agents can also be used in combination with the physical blowing agents described above as a co-blowing agent.

[0063] In one embodiment, the blowing agent is present in an amount of less than about 10 weight%, or less than about 5 weight%, or less than about 4 weight%, or less than about 3 weight%, or less than about 2 weight%, or from about 0.1 weight% to about 5 weight%, or from about 0.1weight% to about 3 weight%, or from about 0.1 weight% to about 1.5 weight%, based upon the total weight of the components used to prepare the foam. Preferably, the blowing agent is water.

[0064] When a catalyst is used, the catalyst is not particularly limited, and any catalyst known in the art may be used. The catalyst may comprise an amine catalyst, such as DABCO (TEDA, triethylenediamine). The catalyst may be present in the foam composition (formed by mixing the isocyanate and isocyanate-reactive components) in an amount of from about 0.001 wt% to about 2 wt%, or from about 0.1 wt% to about 1 wt%, or from about 0.1 wt% to about 0.5 wt%, based upon the total weight of the foam composition. Representative catalysts include, but are not limited to, bis-(2-dimethylaminoethyl)ether (JEFFCAT® ZF-20 catalyst), JEFFCAT® LE- 340 available from Huntsman Corporation, N,N,N'-trimethyl-N'- hydroxyethylbisaminoethylether (JEFFCAT® ZF-10 catalyst), N-(3-dimethylaminopropyl)- N,N-diisopropanolamine (JEFFCAT® DPA catalyst), N,N-dimethylethanolamine (JEFFCAT® DMEA catalyst), triethylene diamine (JEFFCAT® TEDA catalyst), blends of N,N- dimethylethanolamine ethylene diamine (such as JEFFCAT® TD-20 catalyst), N,N- dimethylcyclohexylamine (JEFFCAT® DMCHA catalyst), benzyldimethylamine (JEFFCAT® BDMA catalyst), pentamethyldiethylenetriamine (JEFFCAT® PMDETA catalyst), N,N,N',N",N"- pentamethyldipropylenetriamine (JEFFCAT® ZR-40 catalyst), N,N-bis(3- dimethylaminopropyl)-N-isopropanolamine (JEFFCAT® ZR-50 catalyst), N'-(3- (dimethylamino)propyl -N,N-dimethyl -1,3 -propanediamine (JEFFCAT ® Z- 130 catalyst), 2- (2-dimethylaminoethoxy)ethanol (JEFFCAT® ZR-70 catalyst), N,N,N- trimethylaminoethylethanolamine (JEFFCAT® Z-l 10 catalyst), N-ethylmorpholine (JEFFCAT® NEM catalyst), N- methylmorpholine (JEFFCAT® NMM catalyst), 4-methoxyethylmorpholine, N,N'dimethylpiperzine (JEFFCAT® DMP catalyst), 2,2'-dimorpholinodiethylether (JEFFCAT® DMDEE catalyst), l,3,5-tris(3-(dimethylamino)propyl)-hexahydro-s-triazine (JEFFCAT® TR-90 catalyst), 1- propanamine, 3-(2-(dimethylamino)ethoxy), substituted imidazoles such as 1,2-dimethlyimidazol and l-methyl-2-hydroxyethylimidazole, N,N'- dimethylpiperazines or bis-substituted piperazines such aminoethylpiperazine, N,N',N'- trimethyl aminoethylpiperazine or bis-(N-methyl piperazine)urea, N-methylpyrrolidines and substituted methylpyrrolidines such as 2-aminoethyl-N-methylpyrrolidine or bis-(N- methylpyrrolidine)ethyl urea, 3 -dimethylaminopropylamine, N,N,N",N"- tetramethyldipropylenetriamine, tetramethylguanidine, and 1,2-bis-diisopropanol.

[0065] Suitable surfactants include commercially available surfactants such as Tegostab B8494, Tegostab B8905, Tegostab B8993, Tegostab B8948, Tegostab B8017, Tegostab B8930, Tegostab B8950, Tegostab B8960, Vorasurf DC193, Vorasurf DC198, Vorasurf 5382, Niax L1500, Niax L1550, Niax L1542, Niax UAX 7061, Niax UAX 6897, Niax UAX 6639, Niax UAX 7061, Tegostab B8466 and Tegostab B8416.

[0066] The polyol in the isocyanate-reactive component may consist of the bio-based polyol as described herein, or may comprise the bio-based polyol as described herein and another polyol(s). The additional polyol may be any suitable polyol known in the art, including a polyether polyol, a polyester polyol, or a polycaprolactone. Preferably, the polyol in the isocyanate-reactive component consists of the bio-based polyol as described herein. In one embodiment, the polyol in the isocyanate-reactive component comprises at least 80 weight% of the bio-based polyol as described herein, or at least 90 weight% of the bio-based polyol as described herein, or at least 95 weight% of the bio-based polyol as described herein, based upon the total weight of the polyol in the isocyanate-reactive component.

[0067] According to an embodiment, the isocyanate-reactive component may comprise one or more chain extenders each having a weight-average molecular weight of less than about 500 g / mol, or from about 16 g / mol to about 500 g / mol, or from about 16 g / mol to about 250 g / mol. The amount of chain extender in the isocyanate-reactive component depends upon the intended application of the foam. A chain extender is typically a diol compound. The one or more chain extenders is independently selected from water, 1,6-hexanediol, 1,4-butanediol, monoethylene glycol, diethylene glycol, triethyleneglycol, tetraethyleneglycol, propylene glycol, dipropylene glycol, tripropylene glycol, 1,3 -propanediol, 1,-3-butanediol, 1,5 -pentanediol, poly caprolactone diol, 2-methyl-l,3-propanediol, neopentyl glycol, 1,4-cyclohexanedimethanol, hydroquinone bis (2-hydroxyethyl) ether (HQEE), 1,3-Bis (2-hydroxyethyl) resorcinol (HER), ethanolamine, methyldiethanolamine and / or phenyldiethanolamine, or any combinations thereof.

[0068] The polyisocyanate is not particularly limited, and any polyisocyanate known in the art may be used. The polyisocyanate may comprise an aliphatic polyisocyanate, an aromatic polyisocyanate, a prepolymer of a polyisocyanate, or a combination thereof. The polyisocyanate may comprise an aromatic diisocyanate compound, such as methylene diphenyl diisocyanate (MDI)-based compound. The polyisocyanate may be pure MDI or may be a prepolymer thereof, i.e., a prepolymer made from MDI and a polyol. According to an embodiment, the polyisocyanate may comprise at least 50 weight%, or at least 75 weight%, or at least 80 weight%, or at least 85 weight%, or at least 90 weight%, or at least 95 weight%, or about 100 weight%, of an aromatic diisocyanate, such as MDI (preferably, 4,4'-diphenylmethane diisocyanate) or a prepolymer based upon MDI and a polyol, based upon the total weight of the polyisocyanate.

[0069] Examples of aliphatic polyisocyanates suitable for use include, but are not limited to, hexamethylene diisocyanate (HDI), tetraalkyl xylene diisocyanate, cyclohexane diisocyanate, 1,12-dodecane diisocyanate, 1,4-tetramethylene diisocyanate, 1,3- and 1,4-cyclohexane diisocyanate, 1 -isocyanato-3 ,3 ,5 -trimethyl-5 -isocyanatomethyl -cyclohexane (isophorone diisocyanate), 4,4'-, 2,2'- or 2,4'-dicyclohexyl-methane diisocyanate, as well as the corresponding isomer mixtures.

[0070] Examples of aromatic polyisocyanates suitable for use include, but are not limited to, m- phenylene diisocyanate, p-phenylene diisocyanate, 4,4'- or 2,4'- or 2,2'-diphenylmethane diisocyanate (MDI), polymethylene polyphenylene diisocyanate (mixtures of MDI and oligomers thereof known in the art as “crude” or polymeric MDI having an isocyanate functionality of greater than 2), 2,4- or 2,6-toluene diisocyanate (TDI), dianisidine diisocyanate, bitolylene diisocyanate, naphthalene- 1,4-diisocyanate and diphenylene 4,4'-diisocyanate.

[0071] A prepolymer of the polyisocyanate and the bio-based polyol may be prepared by pre-reacting the bio-based polyol with the polyisocyanate. The prepolymer may then be reacted in the presence of suitable blowing agents, and optionally catalysts and surfactants, to obtain the foam.

[0072] As used herein, the “isocyanate index” is the ratio of NCO-equivalents to the sum of equivalents of isocyanate-reactive hydrogen atoms present in a formulation, given as a percentage:[NCO] x 100 (%)[active hydrogen]In other words, the isocyanate index expresses the percentage of isocyanate actually used in a formulation with respect to the amount of isocyanate theoretically required for reacting with the amount of isocyanate-reactive hydrogen used in a formulation. The expression “isocyanatereactive hydrogen” as used herein for the purpose of calculating the isocyanate index refers to the total of active hydrogen atoms in hydroxyl and amine groups present in the reactive compositions; this means that for the purpose of calculating the isocyanate index at the actual polymerisation process one hydroxyl group is considered to comprise one reactive hydrogen, one primary amine group is considered to comprise one reactive hydrogen and one water molecule is considered to comprise two active hydrogens.

[0073] In one embodiment, the isocyanate index of the foam composition (made by mixing the isocyanate component with the isocyanate-reactive component) is in the range 75 to 125, or 80 to 120, or 85 to 115, or 90 to 115, or 90 to 110. The isocyanate index depends on the type of the foam to be made and its desired properties.

[0074] [A polyurethane foam]

[0075] A polyurethane foam is obtainable by the method described herein. In one embodiment, the polyurethane foam is a flexible foam.

[0076] In one embodiment, the bio-content of the polyurethane foam may be at least 40 weight%, or at least 50 weight%, or at least 60 weight%, or at least 65 weight%, based upon the total weight of the polyurethane foam components excluding water.

[0077] In one embodiment, the polyurethane foam has a Tan delta at 25°C of 0.25 or lower, or 0.2 or lower, or 0. 15 or lower, or 0.1 or lower, or 0.075 or lower, or 0.05 or lower. A low Tan delta is a requirement of a resilient foam.

[0078] Tan delta is measured at 25°C with a DMA Q800 (TA Instruments) equipped with a dual cantilever clamp. The temperature of the sample is increased from -80°C to 100°C at 5°C / min with a frequency of 1Hz and amplitude of 10 pm. Sample size is chosen according to the dimensional ratio indicated by the manual of the testing equipment. The Tan delta is expressed in a graph.

[0079] [An article comprising polyurethane foam]

[0080] The present disclosure provides an article comprising the polyurethane foam. The article may any known article in which a polyurethane foam is useful, and particularly may be an automotive component such as automotive seating and automotive dashboards, or a component of a mattress. In one embodiment, the article may be automotive seating, automotive under-carpet, an automotive dash insulator, or a mattress.

[0081] [Non-limiting embodiments]

[0082] In an embodiment of the present disclosure, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1: 13 to 1:30, and wherein the initiator has a weight-average molecular weight of below 750 g / mol.

[0083] In an embodiment of the present disclosure, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 13 to 1:30, wherein the initiator has a weight-average molecular weight of below 750 g / mol, and wherein the initiator is an alkoxylated sugar alcohol.

[0084] In an embodiment of the present disclosure, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 13 to 1 :25, wherein the initiator has a weight-average molecular weight of below 550 g / mol, and wherein the initiator is alkoxylated sorbitol.

[0085] In an embodiment of the present disclosure, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 13 to 1:30, wherein the initiator has a weight-average molecular weight of below 550 g / mol, wherein the initiator is an alkoxylated sugar alcohol, and whereinthe bio-derived hydroxyl-containing fatty acid or ester thereof is ricinoleic acid or an ester thereof.

[0086] In an embodiment of the present disclosure, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least four hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 14 to 1:30, wherein the initiator has a weight-average molecular weight of below 550 g / mol, wherein the initiator is an alkoxylated sugar alcohol, and wherein the bioderived hydroxyl-containing fatty acid or ester thereof is ricinoleic acid or an ester thereof.

[0087] In an embodiment of the present disclosure, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising from 4 to 8, preferably 6, hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 14 to 1:30, wherein the initiator has a weightaverage molecular weight of below 650 g / mol, and wherein the bio-content of the bio-based polyol is 80 weight% or more, based upon the total weight of the bio-based polyol.

[0088] In an embodiment of the present disclosure, there is provided a method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising six hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1: 13 to 1: 19, wherein the initiator is ethoxylated or propoxylated sorbitol, wherein the bio-derived hydroxyl-containing fatty acid or ester thereof is ricinoleic acid or an ester thereof, and wherein the ethoxylated or propoxylated sorbitol is prepared by reacting 5 to 7, preferably 6, mole equivalents of ethylene oxide or propylene oxide with 1 mole equivalent sorbitol.

[0089] [Examples]

[0090] The present disclosure will be described in more detail with reference to the Examples. The present disclosure is not limited to the following Examples.

[0091] [Synthesis Example 1]

[0092] Bio-based polyol 1 was prepared as follows:

[0093] 92.2 pbw of bio-based ricinoleic acid (85% pure, available from Oleon (Nouracid CZ80)) were reacted with 7.5 pbw of ethoxylated sorbitol (59% ethylene oxide by weight) in the presence of 0.1 pbw zinc acetate, 0.005 pbw titanium tetrabutoxide and 0.2 pbw Niax™ CS-15 (a colour stabilizer, available from Momentive). The molar ratio of ricinoleic acid to ethoxylated sorbitol corresponded to about 19: 1.

[0094] The reaction was performed at 200°C under inert atmosphere until the acid value was measured below 1 mgKOH / g (measured by ASTM D4662). Water formed during the polycondensationreaction was removed at atmospheric pressure. The properties of the obtained polyester (biobased polyol 1) were as follows: viscosity at 25°C was 2.7 Pa s, measured using Brookfield R / S-CPS-P2 Rheometer; the hydroxyl value was 28 mgKOH / g, determined via potentiometric titration (theoretical expected value = 28.7); bio-content in polyol = 95.3 wt%, based upon total weight of the polyol; calculated molecular weight 5400 g / mol; andOH functionality 3.0.

[0095] [Synthesis Example 2]

[0096] Bio-based polyol 2 was prepared as follows:

[0097] 89.1 pbw of bio-based ricinoleic acid (85% pure, available from Oleon (Nouracid CZ80)) were reacted with 10.7 pbw of ethoxylated sorbitol (59% ethylene oxide by weight) in the presence of 0.1 pbw zinc acetate, 0.005 pbw titanium tetrabutoxide and 0.2 pbw Niax™ CS-15 (a colour stabilizer, available from Momentive). The molar ratio of ricinoleic acid to ethoxylated sorbitol corresponded to about 13: 1.

[0098] The reaction was performed at 200°C under inert atmosphere until the acid value was measured below 1 mgKOH / g (measured by ASTM D4662). Water formed during the polycondensation reaction was removed at atmospheric pressure. The properties of the obtained polyester (biobased polyol 2) were as follows: viscosity at 25°C was 2.2 Pa s, measured using Brookfield R / S-CPS-P2 Rheometer; the hydroxyl value was 54 mgKOH / g, determined via potentiometric titration (theoretical expected value = 55.7); bio-content in polyol = 93.5 wt%, based upon total weight of the polyol; calculated molecular weight 3900 g / mol; andOH functionality 3.8.

[0099] [Synthesis Example 3]

[0100] Bio-based polyol 3 was prepared as follows:

[0101] 85.5 pbw of bio-based ricinoleic acid (85% pure, available from Oleon (Nouracid CZ80)) were reacted with 14.1 pbw of propoxylated sorbitol (75% propylene oxide by weight) in the presence of 0.1 pbw zinc acetate, 0.007 pbw titanium tetrabutoxide and 0.2 pbw Niax™ CS-15 (a colour stabilizer, available from Momentive). The molar ratio of ricinoleic acid to propoxylated sorbitol corresponded to about 15: 1.

[0102] The reaction was performed at 200°C under inert atmosphere until the acid value was measured below 1 mgKOH / g (measured by ASTM D4662). Water formed during the polycondensation reaction was removed at atmospheric pressure. The properties of the obtained polyester (biobased polyol 3) were as follows:Viscosity at 25°C was 3.2 Pa s, measured using Brookfield R / S-CPS-P2 Rheometer; the hydroxyl value was 44 mgKOH / g, determined via potentiometric titration (theoretical expected value = 43.4); bio-content in polyol = 89.0%, based upon total weight of the polyol; calculated molecular weight 4500 g / mol; and OH functionality 3.5.

[0103] [Example 1]

[0104] Flexible polyurethane foam 1 was prepared as follows:

[0105] 10 grams of isocyanate SUPRASEC® 2447 (a polymeric MDI, available from Huntsman Corporation) were pre-reacted with a blend of 23 ,5g of bio-based polyol 1 prepared in synthesis example 1 and 2.34 g of bio-based polyol 2 prepared in synthesis example 2. The obtained prepolymer was subsequently reacted with: 0.05 g of diethanolamine, 0.06 g of JEFFCAT® ZF- 10 (a catalyst, available from Huntsman Corporation), 0.34 g of JEFFCAT® LE-340 (a catalyst, available from Huntsman Corporation), 0.55 g of water and 0.13 g ofVORASURF® DC198 (a surfactant, available from DOW). The mixture was stirred at 2000 rpm for 5-10 seconds, poured into an open mould and allowed to foam (free-rise).

[0106] The obtained foam (isocyanate index 102) had a density of approximately 70 kg / m3and a Tan delta at 25°C = 0.04 (measured with DMA Q800, as described above). The bio-content of the foam = 67.3%. Bio-content is expressed as the weight % of bio-based material on total foam components excluding water.

[0107] [Example 2]

[0108] Flexible polyurethane foam 2 was prepared as follows:

[0109] 9.75 grams of isocyanate SUPRASEC® 2447 (a polymeric MDI, available from Huntsman Corporation) were pre-reacted with a blend of 23 ,5g of bio-based polyol 1 prepared in synthesis example 1 and 2.34 g of bio-based polyol 2 prepared in synthesis example 2. The obtained prepolymer was subsequently reacted with: 0.05 g of diethanolamine, 0.06 g of JEFFCAT® ZF- 10 (a catalyst, available from Huntsman Corporation), 0.34 g of JEFFCAT® LE-340 (a catalyst, available from Huntsman Corporation), 0.1 g of JEFFCAT® DMEA (a catalyst, available from Huntsman Corporation), 0.45 g of water and 0.13 g of VORASURF® DC198 (a surfactant, available from DOW). The mixture was stirred at 2000 rpm for 5-10 seconds, poured into an open mould and allowed to foam (free-rise).

[0110] The obtained foam (isocyanate index 112) had a density of approximately 110 kg / m3. The biocontent of the foam = 67.7%. Bio-content is expressed as the weight % of bio-based material on total foam components excluding water.

[0111] [Example 3]

[0112] Flexible polyurethane foam 3 was prepared as follows:

[0113] 9.75 grams of isocyanate SUPRASEC® 2447 (a polymeric MDI, available from Huntsman Corporation) were pre-reacted with a blend of 23 ,5g of bio-based polyol 1 prepared in synthesis example 1. The obtained prepolymer was subsequently reacted with: 0.05 g of diethanolamine, 0.06 g of JEFFCAT® ZF-10 (a catalyst, available from Huntsman Corporation), 0.34 g of JEFFCAT® LE-340 (a catalyst, available from Huntsman Corporation), 0.1 g of JEFFCAT® DMEA (a catalyst, available from Huntsman Corporation), 0.55 g of water and 0.26 g of VORASURF® DC198 (a surfactant, available from DOW). The mixture was stirred at 2000 rpm for 5-10 seconds, poured into an open mould and allowed to foam (free-rise).

[0114] The obtained foam (isocyanate index 100) had a density of approximately 80 kg / m3and a Tan delta at 25°C = 0.07. The bio-content of the foam = 65.7%. Bio-content is expressed as the weight % of bio-based material on total foam components excluding water.

[0115] It is evident from Synthesis Examples 1-3 that bio-based polyols having a high bio-content can be successfully synthesised according to the method of the present disclosure. The obtained polyols have low viscosity, which enables easier processing of the polyol when making a foam.

[0116] It is evident from Examples 1-3 that the bio-based polyols of Synthesis Examples 1-3 are useful in the preparation of polyurethane foams, particularly flexible polyurethane foams. The Tan delta value for each polyurethane foam of Examples 1 and 3 was significantly below 0.1 at 25 °C, which is required for a highly resilient foam. The bio-content of each of the foams of Examples 1-3 was also very high, with the lowest being 65.7%, which demonstrates a significant advancement in green chemistry in connection with the production of polyurethane foams having excellent mechanical properties (such as resilience, etc.).

[0117] All ranges described herein are exemplary in nature and include any and all values in between. The terms “substantially”, “approximately” and “about” used herein are interchangeable and refer to a measurement that includes the stated measurement and any measurements reasonably close to the stated measurement. Measurements that are reasonably close to the stated measurement deviate from the stated measurement by a reasonably small amount as understood and readily ascertained by individuals having ordinary skill in the relevant art. Such deviations may be attributable to measurement error, differences in measurement and / or manufacturing equipment calibrations, human error in reading and / or setting measurements, minor adjustments made to optimize performance and / or structural parameters in view of differences in measurement associated with other components, particular implementation scenarios, imprecise adjustment and / or manipulation of objects by a person or machine. In the event it is determined that individuals having ordinary skill in the relevant art would not readily ascertain values for such reasonably small differences, the terms “about” and “approximately” can be understood to mean plus or minus 10% of the stated value.

[0118] Throughout the description and claims, the terms take the meanings explicitly defined herein, unless the context clearly dictates otherwise.

[0119] The phrases “in one embodiment”, “in an embodiment” and “in some embodiments” etc. as used herein do not necessarily refer to the same embodiment(s), though they may. Furthermore, the phrases “in another embodiment” and “in some other embodiments” as used herein do not necessarily refer to a different embodiment, though they may. All embodiments of the present disclosure are intended to be combinable.

[0120] The terms “comprises” and “comprising” mean to include but not limited to, such that further features may be present. The terms may also mean to consist of or consist essentially of.

[0121] All references and test methods cited herein are incorporated by reference in their entireties.

Claims

CLAIMS1. A method of preparing a bio-based polyol, the method comprising: reacting a fatty acid component comprising a bio-derived hydroxyl-containing fatty acid or ester thereof with an initiator comprising at least three hydroxyl groups to obtain the bio-based polyol, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 13 or greater.

2. A method according to Claim 1, wherein the initiator comprises from 4 to 8 hydroxyl groups.

3. A method according to Claim 1 or Claim 2, wherein the initiator has a weight-average molecular weight of 750 g / mol or lower.

4. A method according to any preceding claim, wherein the initiator is a polyether polyol, preferably wherein the polyether polyol is an alkoxylated polyol, and most preferably wherein the polyether polyol is an ethoxylated or propoxylated polyol.

5. A method according to Claim 4, wherein the polyol is one or more sugar alcohol(s), preferably sorbitol.

6. A method according to any preceding claim, wherein the bio-derived hydroxyl-containing fatty acid or ester thereof comprises a secondary hydroxyl group.

7. A method according to any preceding claim, wherein the bio-derived hydroxyl-containing fatty acid or ester thereof comprises at least 9 carbon atoms.

8. A method according to any preceding claim, wherein the bio-derived hydroxyl-containing fatty acid or ester thereof is derived from a naturally-occurring vegetable oil, wherein preferably the bio-derived hydroxyl-containing fatty acid or ester thereof derived from a naturally-occurring vegetable oil is a purified form thereof.

9. A method according to any preceding claim, wherein the bio-derived hydroxyl-containing fatty acid or ester thereof comprises ricinoleic acid or an ester thereof.

10. A method according to any preceding claim, wherein the molar ratio of the initiator to the fatty acid component is from 1 : 14 to 1:19.

11. A method according to any preceding claim, wherein the weight-average molecular weight of the bio-based polyol is at least 3000 g / mol, preferably at least 3500 g / mol, and / or wherein the viscosity at 25°C of the bio-based polyol is below 10 Pa.s.

12. A method according to any preceding claim, wherein the bio-content of the bio-based polyol is at least 80 weight%, based upon the total weight of the bio-based polyol.

13. A bio-based polyol obtainable by the method according to any of Claims 1-12.

14. A method of preparing a polyurethane foam, the method comprising: providing an isocyanate-reactive component comprising the bio-based polyol as defined in Claim 13; providing an isocyanate component comprising a polyisocyanate; and reacting the isocyanate-reactive component and isocyanate component, in the presence of a blowing agent, to obtain the polyurethane foam.

15. A polyurethane foam obtainable by the method according to Claim 14, preferably wherein the polyurethane foam is a flexible polyurethane foam having a Tan delta at 25°C of 0.25 or lower.

16. An automotive seat, automotive under-carpet, automotive dash insulator, or mattress comprising the foam as defined in Claim 15.

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