WO2013053665A1

WO2013053665A1 - Polyurethane, its preparation process and uses thereof

Info

Publication number: WO2013053665A1
Application number: PCT/EP2012/069853
Authority: WO
Inventors: Zhiping Zhou; John Zhang; Jingui Shi
Original assignee: Bayer Intellectual Property GmbH
Current assignee: Bayer Intellectual Property GmbH
Priority date: 2011-10-11
Filing date: 2012-10-08
Publication date: 2013-04-18
Anticipated expiration: 2014-04-11
Also published as: CN103044648A; CN103044648B

Abstract

The present invention relates to a polyurethane, a preparation process and uses thereof. The polyurethane provided herein comprises a reaction product of the following components comprising: diisocyanate, polyisocyanate or isocyanate terminated prepolymer; polyol; carbonate; carboxylate; optionally catalyst; optionally chain extender; optionally blowing agent and/or surfactant. The molar ratio of the carbonate groups in the carbonate and the carboxylate groups in the carboxylate is 0.85-3.40. The polyurethane prepared by the method of the present invention has good physical and mechanical properties, especially good hydrolysis resistance properties.

Description

TITLE OF THE INVENTION

Polyurethane, Its Preparation Process and Uses Thereof

FIELD OF THE INVENTION

[0001] The present invention relates to polyurethane field, particular to polyurethane, its preparation process and uses thereof.

BACKGROUND OF THE INVENTION

[0002] The hydrolysis resistance of polyester-polyurethanes has been a concern in its application. This is because during application, the ester bonds within their structure are hydro lyzed by the exposure to moisture or by direct contact with water, thus leading to breaking of polymer chain and gradual, even complete loss of their physical properties. Therefore, it has always been a research topic in material science to improve hydrolysis resistance of these polyester-polyurethanes.

[0003] The hydrolysis resistance of polyurethane may be improved by adding certain amount of anti-hydrolysis additive, which is widely used due to its simplicity and convenience. GB 1205257A disclosed that alkylene carbonates can effectively improve hydrolysis resistance of polyurethanes. US 6737471B2 disclosed that ester(s) of (mono)carboxylic acid is an effective anti-hydrolysis additive for polyurethanes as long as the (first) dissociation constant (pKa) of the respective carboxylic acid is between 0.5 and 4.0. In addition, the resulted polyurethane has the best hydrolysis resistance when the amount of the carboxylate added falls into a specified range.

SUMMARY OF THE INVENTION

[0004] One object of the present invention is to provide a polyurethane having improved hydrolysis-resistance., according to an embodiment of the invention, such

polyurethane is the reaction product prepared by reacting the components comprising A)-G):

A) one or more diisocyanate, polyisocyanate, or isocyanate terminated

prepolymer prepared by reacting isocyanate with a first polyol; B) one or more of a second polyol;

C) one or more carbonate;

D) one or more carboxylate with a first dissociation constant of the respective carboxylic acid in the range of 0.5-4; E) optionally one or more catalyst;

F) optionally one or more chain extender having a molecular weight less than

800; and

G) optionally one or more blowing agent and/or surfactant; wherein at least one of the first polyol and the second polyol is polyester polyol. Preferably, the polyester polyol has a hydroxyl number of 20-280 mgKOH/g and a functionality of 1-3.

[0005] In one embodiment of the present invention, the molar ratio of the carbonate

groups in the carbonate to the carboxylate groups in the carboxylate is 0.85-3.40.

[0006] In one embodiment of the present invention, the carbonate is cyclic carbonate and/or linear carbonate.

[0007] In another embodiment of the present invention, the carbonate is one or more cyclic carbonate selected from the group consisting of ethylene carbonate, propylene carbonate, 1 ,2-butene carbonate, 2,3-butene carbonate, 1 ,2-cyclohexene carbonate and styrene carbonate. [0008] In yet another embodiment, the carboxylate is one or more selected from the group consisting of dimethyl oxalate, diethyl oxalate , dibutyl oxalate, γ-butyro lactone, γ- valerolactone, ε-caprolactone, α,γ-dimethyl butyrolactone, β,γ-dimethyl

butyro lactone, γ,γ-dimethyl butyrolactone and a-ethyl-y-methyl butyrolactone.

[0009] In yet another embodiment, the two-week hydrolysis resistance of the

polyurethane is 40-100% of the retention of tensile strength, determined according to

SATRA TM344.

[0010] A second object of the present invention is to provide a process for preparing polyurethane, which comprises a step of reacting the components comprising A)-G):

A) one or more diisocyanate, polyisocyanate, or isocyanate terminated prepolymer prepared by reacting isocyanate with a first polyol;

B) one or more of a second polyol;

C) one or more carbonate;

D) one or more carboxylate with a first dissociation constant of a respective carboxylic acid of 0.5-4;

E) optionally one or more catalyst;

F) optionally one or more chain extender having a molecular weight less than

800; and

[0011] In one embodiment of the present invention, the molar ratio of the carbonate

[0012] In one embodiment of the present invention, the carbonate is cyclic carbonate and/or linear carbonate.

[0013] In another embodiment, the carbonate is the one or more cyclic carbonate selected from the group consisting of ethylene carbonate, propylene carbonate, 1 ,2-butene carbonate, 2,3-butene carbonate, 1 ,2-cyclohexene carbonate and styrene carbonate.

[0014] In another embodiment, the carboxylate is the one or more selected from the group consisting of dimethyl oxaloacetate, diethyl oxaloacetate, dibutyl oxaloacetate, γ- butyro lactone, γ-valero lactone, s-caprolactone,a,y-dimethyl butyro lactone, β,γ- dimethyl butyrolactone, γ,γ-dimethyl butyro lactone and a-ethyl-y-methyl

butyro lactone.

[0015] In yet another embodiment, the two-week hydrolysis resistance of the

polyurethane is 40-100% of the retention of tensile strength, determined according to SATRA TM344.

[0016] A third object of the present invention is to provide a use of the polyurethane in preparing polyurethane foams, microcellular elastomers and elastomers. [0017] Polyurethanes prepared with the process of the present invention possess good physical mechanical properties, especially good hydrolysis resistance. Polyurethanes of the present invention are particularly suitable for preparing polyurethane foams, microcellular elastomers and elastomers.

DETAILED DESCRIPTION OF THE INVENTION

[0018] Surprisingly, the applicant find that in comparison with only adding carbonate or carboxylate, adding both carbonate and carboxylate during the preparation process of polyurethanes may significantly improve the hydrolysis resistance of obtained polyurethanes. In particular, the technical effect is more prominent when the molar ratio of the carbonate to the carboxylate is in the preferred range.

Polyurethane

[0019] Compared with the existing technologies, polyurethanes obtained by adding both carbonate and carboxylate in the preparation process has improved hydrolysis resistance. Preferably, the hydrolysis resistance of the polyurethane is further improved when the molar ratio of the carbonate groups in the carbonate to the carboxylate groups in the carboxylate is 0.85-3.40.

[0020] Polyurethanes provided in the present invention is the reaction product prepared by reacting the components comprising A)-G):

A) one or more diisocyanate, polyisocyanate, or isocyanate terminated

prepolymer prepared by reacting isocyanate with a first polyol;

B) one or more of a second polyol;

C) one or more carbonate;

E) optionally one or more catalyst;

F) optionally one or more chain extender with a molecular weight of less than

800; and

G) optionally one or more blowing agent and/or surfactant; wherein at least one of the first polyol and the second polyol is polyester polyol.

[0021] Preferably, the polyester polyol has a hydroxyl number of 20-280 mgKOH/g and a functionality of 1-3. The measurement of hydroxyl number is well known to a person skilled in the art, for example, as disclosed in Houben Weyl, Methoden der

Organischen Chemie, vol. XIV/2 Makromolekulare Stoffe, p.17, Georg Thieme Verlag; Stuttgart, 1963, which is incorporated by reference herein in its entirety.

[0022] Component A) comprises one or more diisocyanate and/or polyisocyanate, such diisocyanate and/or polyisocyanate may be one diisocyanate and/or polyisocyanate, or the mixture of more than one diisocyanate and/or polyisocyanate. The

diisocyanate and/or polyisocyanate may be expressed by a general formula, R(NCO)«, wherein R represents an aliphatic hydrocarbon radical containing 2-18 carbon atoms, an aromatic hydrocarbon radical containing 6-15 carbon atoms, or an araliphatic hydrocarbon radical containing 8-15 carbon atoms, and n = 2-4.

[0023] Examples of said diisocyanate and/or polyisocyanate include but not limited to

ethylene diisocyanate, 1 ,4-tetramethylene diisocyanate, 1,6-hexamethylene diisocyanate (HDI), 1,2-dodecane diisocyanate, eye lo butane- 1,3-diisocyanate, cyclohexane-1,3- and 1,4-diisocyanates, l-isocyanato-3,3,5-trimethyl-5-isocyanatomethyl-cyclohexane, 2,4- and 2,6-hexahydrotoluene diisocyanates, hexahydro-1,3- and 1 ,4-phenylene diisocyanate, perhydro-2,4- and 4,4-diphenylmethane diisocyanate, 1,3-and 1 ,4-phenylene diisocyanate, 1 ,4-durol-diisocyanate, 4,4'-stilbene diisocyanate, 3,3-dimethyl-4,4-biphenylene diisocyanate, toluene-,4- and 2,6-diisocyanates (TDI), diphenylmethane-2,4'-, 2,2'- and 4,4'-diisocyanates (MDI), and naphthylene-l,5-diisocyanate (NDI), the mixtures thereof, the isomer thereof, the mixtures of them and the isomer thereof.

[0024] The diisocyanate and/or polyisocyanate may also include those modified by

carbon diamine, allophanate and isocyanate, which are preferably but not limited to diphenylmethane diisocyanate modified by diphenylmethane diisocyanate and allophanate, , their isomers, and the mixtures thereof.

[0025] The isocyanante-terminated prepolymer of the present invention is the reaction product of the isocyanate and the first polyol, wherein the isocyanate may be any isocyanate monomer mentioned above. [0026] The first polyol may further comprise polyester polyol, polyether polyol, polycarbonate diol and mixtures thereof.

[0027] The polyester polyols may be produced from the reaction of organic dicarboxylic acids or dicarboxylic acid anhydrides with polyhydric alcohols. Suitable dicarboxylic acids are preferably, but not limited to aliphatic carboxylic acids containing 2 to 12 carbon atoms, which in turn are preferably, but not limited to succinic acid, malonic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, decane- dicarboxylic acid, maleic acid, fumaric acid, phthalic acid, isophthalic acid, terephthalic acid or mixtures thereof. Suitable anhydrides are, preferably but not limited to phthalic anhydride, terachlorophthalic anhydride, maleic anhydride or mixtures thereof. Said polyhydric alcohols are preferably, but not limited to ethanediol, diethylene glycol, 1 ,2- and 1 ,3-propanediols, dipropylene glycol, 1 ,3- methylpropanediol, 1 ,4-butanediol, 1 ,5-pentanediol, 1 ,6-hexanediol, neopentyl glycol, 1 , 10-decanediol, glycerol, trimethylol-propane, or mixtures thereof. Polyester polyols of lactones are preferably, but not limited to ε-caprolactone,.

[0028] The polyether polyols may be produced by known process, for example, through the reaction of alkylene oxides with polyhydric alcohol starters in the presence of catalysts. Said catalysts are preferably, but not limited to alkali hydroxides, alkali alkoxides, antimony pentachloride, boron fluoride etherate or mixtures thereof. Said alkylene oxides are preferably, but not limited to tetrahydrofuran, ethylene oxide, 1 ,2-propylene oxide, 1 ,2-and 2,3-butylene oxide, styrene oxide or mixtures thereof. Suitable starter molecules are preferably, but not limited to polyhydric compounds, such as water, ethylene glycol, 1 ,2-and 1 ,3-propanediols, 1 ,4-butanediol, diethylene glycol, trimethylol-propane or mixtures thereof.

[0029] The polycarbonate polyols may be produced from the reaction of diols such as 1 ,2- and 1 ,3-propanediols, 1 ,4-butanediol, 1 ,5-pentanediol, 1 ,6-hexanediol, diethylene glycol, trioxyethylene glycol, with dialkyl or diaryl carbonates, eg. diphenyl carbonate, or phosgene. [0030] The component B) comprises one or more second polyol. The second polyol is as defined as the first polyol, which may be the same as the first polyol or different, and at least one of the first polyol and the second polyol is polyester polyol. Preferably, the polyester polyol has a hydroxyl value of 20-280 mgKOH/g and a functionality of 1-3.

[0031] The component C) comprises one or more carbonate. The carbonate may be the one selected from the group consisting of cyclic carbonate or linear carbonate, more preferably cyclic carbonate. The carbonate may be the one or more selected from the group consisting ethylene carbonate, propylene carbonate, 1 ,2-butene carbonate, 2,3- butene carbonate, 1 ,2-cyclohexene carbonate and styrene carbonate, more preferably ethylene carbonate or propylene carbonate, the most preferably ethylene carbonate. The amount of the carbonate may be 0.5-15% based on 100% by weight of the polyurethane.

[0032] The component D) comprises one or more carboxylate which has a dissociation constant of carboxylic acid of 0.5-4. The dissociation constant refers to the first dissociation constant when the carboxylate is dicarboxylate or polycarboxylate.

[0033] The component E) comprises one or more catalyst which is preferably, but not limited to, amines and organic metal compounds and their mixtures. The amine catalyst is preferably, but not limited to, triethylamine, tributylamine, triethylene diamine, N-ethylmorpholine, Ν,Ν,Ν',Ν'-tetramethyl-ethylenediamine, pentamethyl diethylene-triamine, N,N-methylaniline, Ν,Ν-dimethylaniline and mixtures thereof. The organic metal catalyst is preferably, but not limited to, stannous diacetate, stannous dioctoate, stannous diethylhexoate, and dibutyltin diacetate, dibutyltin dilaurate, ditutyltin maleate, and dioctyltin diacetate and mixtures thereof. The catalyst dosage is 0.001-10wt.%> based on 100 % by weight of the polyurethane.

[0034] The component F) comprises one or more chain extender, which typically is

selected from active hydrogen atoms comprising compounds with molecular weights lower than 800, preferably from 18 to 400. The active hydrogen atoms comprising compounds are preferably, but are not limit to alkanediols, dialkylene glycols, and polyalkylene polyols and their mixtures. The examples are ethanediol, 1 ,4- butanediol, 1 ,6-hexanediol, 1 ,7- heptane diol, 1 ,8-octanediol, 1 ,9-nonanediol, 1 , 10- decanediol, diethylene glycol, dipropylene glycol, and polyoxyalkylene glycols.

Other suitable substances are branched chain and unsaturated alkanediols such as 1 ,2- propanediol, 2-methyl- 1 ,3-propanediol,2,2-dimethyl- 1 ,3-propanediol, 2-butyl-2- ethyl- 1 ,3-propanediol, 2-butene-l ,4-diol and 2-butyne- l ,4-diol, alkanolamines and N- alkyldialkanolamines such as ethanolamine, 2-aminopropanol and 3-amino-2,2- dimethylpropanol, N-methyl and N- ethyl- diethanolamines, as well (cyclo) aliphatic and aromatic amines, e.g. 1 ,2 ethylenediamine, 1 ,3-propylenediamine, 1 ,4- butylenediamine, 1 ,6-hexamethylenediamine,isophoronediamine, 1 ,4- cyclohexamethylenediamine, Ν,Ν'-diethyl-phenylenediamine, and 2,4 and 2,6- diaminotolune and mixtures thereof.

[0035] The component G) comprises one or more blowing agent and/or surfactant.

[0036] Suitable blowing agent is preferably but not limited to water, halohydrocarbons, hydrocarbons and gases. Examples of halohydrocarbons are

monochlorodifuloromethane, dichloromonofluoromethane, dichlorofluoromethane, and trichlorofluromethane. Examples of hydrocarbons include butane, pentane, cyclopentane, hexane, cyclohexane, and heptane. Blowing gases include, but not limited to, air, C0₂, and N₂.

[0037] The surfactants are selected preferably from but not limited to polyoxyalkylene derivatives of siloxane, in an amount of 0.01 to 5%, based on 100% by weight of the polyurethanes.

The process of preparing polyurethane

[0038] In the process of preparing the polyurethanes, the equipment to mix all the

reaction components can be a high-pressure or low-pressure mixing-head machine, preferably low-pressure mixing-head machine. The mixing process can be a two- component mixing or multi-component mixing. For detailed procedures, please refer to handbook (Kunststoff Handbuch, Volume VII, Polyurethanes, 1994 by Dr. G. Oertel, Carl-Hanser-Verlag, Munich). The molds described herein are those frequently used in the existing technology to prepare polyurethanes, in which the reaction system can react to provide the polyurethanes of the present invention. The polyurethane molding technology and equipment are those well-known in related fields. For details, please refer to "Polyurethanes Chemistry and Technology"

(Saunders H and Frisch KC, Part II. 4th print. New York: Interscience Publ., Wiley & Sons, 1967) and "Polyurethane handbook: chemistry, raw materials, processing, application, properties" (Giinter Oertel and Lothar Abele, 2nd edition, Hanser Gardner Publ., 1993), etc.

[0039] The process of preparing polyurethane provided in the present invention comprises a step of reacting the components comprising A)-G):

A) one or more diisocyanate, polyisocyanate, or isocyanate terminated

prepolymer prepared by reacting the isocyanate with the first polyol; B) one or more the second polyol;

C) one or more carbonate;

D) one or more carboxylate with the dissociation constant of carboxylic acid of

0.5-4;

E) optional one or more catalyst; F) optional one or more extender with a molecular weight of less than 800; and

G) optional one or more blowing agent and/or surfactant, wherein at least one of the first polyol and the second polyol is polyester polyol.

[0040] The first polyol and the second polyol may be the same or different, and at least one of the first polyol and the second polyol is polyester polyol. Preferably, the polyester polyol has a hydroxyl value of 20-280 mgKOH/g and a functionality of 1-3.

[0041] Preferably, the molar ratio of the carbonate groups in the carbonate to the carboxyl groups in the carboxylate is 0.85-3.40

[0042] the molar ratio of the carbonate groups in the carbonate to the carboxyl groups in the carboxylate is defined as following: _l ■ (mass of the carbonate÷molecular weight of the carbonate)

[0043] mole ratio =— ^ — ^{■ ■ ■}—^■ —— ^■ -^—

(mass of the carboxylate÷molecular weight of the carboxylate)

[0044] The reaction component comprising A)-G) can react in molds to provide the

polyurethane of the present invention. The polyurethane may be also obtained by the way of spraying, rolling and brushing the mixture comprising component A)-G). The model may be those generally used in the prior art or designed according to special requirements.

[0045] The NCO Index X(%) is defined as:

[moles of isocyanate group (NCO group) in the recation components] [moles of isocyanate reactive group comprised in the reaction components]

[0046] The NCO Index of the reaction is preferred but not limited to be 50-160, particularly preferred 80-120, and may be optimized by the method well-known in prior art.

[0047] All the references described above are incorporated by reference in their entireties for all useful purposes.

[0048] While there is shown and described certain specific structures embodying the invention, it will be manifest to those skilled in the art that various modifications and rearrangements of the parts may be made without departing from the spirit and scope of the underlying inventive concept and that the same is not limited to the particular forms herein shown and described.

EXAMPLES

[0049] The following examples are illustrative only, and are not intended to limit the scope of the present invention.

[0050] The materials used in the examples are listed in the below table:

Adipate polyester polyol, having an average

molecular weight of 2000, an OH number of Available from Bayer

Bayflex 2003E

56 mgKOH/g and a functionality of 2 Material Science;

Polyester-type isocyanate terminated Available from Bayer

Desmodur 0926

prepolymer, NCO content 19.3% Material Science;

Dabco EG amine catalysts Available from Air Products and Chemicals

Available from Air

Dabco DC 193 Siloxane surfactant Products and Chemicals

Preparation of the Polyurethane

[0051] Desmodur 0926, isocyanate terminated prepolymer was marked as Component I.

[0052] The other components (such as polyols, chain extenders, blowing agents, catalysts and surfactants) were marked as Component II.

[0053] Diethyl oxalate and ethylene carbonate were marked as Component III.

[0054] In the examples of the present invention, the polyurethane shoe sole samples were

prepared using Desma injection machine.

Testing method and standard [0055] The hydrolysis-resistance properties of the polyurethane samples prepared according to the method described in this invention were evaluated by measuring the retention of tensile strengths before and after subjecting the polyurethane samples to hydrolysis conditions. Tensile strength was tested according to DIN53504. Hydrolysis conditions were established according to SATRA TM344, specifically, the samples were placed under 70^°C, 95% relative humidity, for certain periods (one week and two weeks). The samples were placed in room temperature for 24 hours before testing.

Examples E1-E5 and Comparative Examples C1-C3

[0056] The amounts of all components used to prepare polyurethane samples in E1-E5 and Cl- C3, and their hydrolysis testing results, were listed in Table 1. Component II was mixed by using a mechanical stirrer and then loaded into Tank 1 of an injection molding machine at

45^°C.

[0057] Component I and Component III were then introduced into Tank 2 at 45 ^°C. [0058] All components were mixed by a mixing head of a shoe sole injection molding machine, and the mixture were injected into an aluminum mold. The temperature of the mold was 50^°C. The NCO index of the reaction mixture can be optimized by the methods well known in the art. [0059] The mold was closed, and the foam was demolded after four minutes to obtain a

polyurethane sample.

[0060] The hydrolysis-resistance properties of the obtained polyurethane samples were evaluated by measuring the relative tensile strength retention as listed in Table I.

Table 1 hydrolysis-resistance test results of polyurethane samples

Example CI C2 C3 El E2 E3 E4 E5

Component Desmodur 0926 85 86 84 85 86 87 85 84 I (parts by weight)

Component Bayflex 2003E 100 100 100 100 100 100 100 100- II (parts by weight)

Glycol (parts by 7 7 7 7 7 7 7 7 weight)

Dabco EG (parts by 1.5 1.5 1.5 1.5 1.5 1.5 1.5 1.5 weight)

DC 193 (parts by 0.4 0.4 0.4 0.4 0.4 0.4 0.4 0.4 weight)

water (%) 0.45 0.45 0.45 0.45 0.45 0.45 0.45 0.45

Component diethyl oxaloacetate - 1 - 1 1.5 2 0.7 1 III (parts by weight)

ethylene carbonate - - 1 1 1 1 1 2 (parts by weight)

molar ratio of the carbonate groups 1.66 1.11 0.83 2.37 3.32 in the carbonate and the carbonate

groups in the carboxylate

density (kg/m³) 550 550 550 550 550 550 550 550

Physical tensile strength 6.1 5.7 5.7 5.6 5.4 5.6 5.7 5.7 properties (MPa), 0 week tensile strength 4.9/ 5.5/ 5.0/ 5.6/ 5.7/ 5.9/ 5.6/ 6.3/ (MPa)/ relative 81% 98% 88% 100% 105% 106% 99% 110% retention (%>), 1

week

tensile strength 2.3/ 3.2/ 2.1/ 3.6/ 3.8/ 4.1/ 3.1/ 5.4/

(MPa)/ relative 38% 57% 37% 64% 70% 74% 55% 95% retention (%) , 2

week

[0061] Regarding to comparative Examples CI and C3, in the one week and two weeks

hydrolysis tests of the obtained polyurethane samples (density 550kg/m3), C3 showed no obvious improvement in hydro lytic stability compared with CI; thus, ethylene carbonate alone did not have obvious impact on the hydrolysis-resistance property. However,

Examples E1-E5 showed better hydrolysis-resistance properties in comparison to C2, which indicated that the combination of ethylene carbonate and diethyl oxalate can significantly improve the hydrolytic stability of the obtained polyurethane samples. In particular, E5, the polyurethane sample obtained at optimum ratio of ethylene carbonate to diethyl oxalate, showed significant improvement of hydrolytic stability after two weeks of hydrolysis.

Moreover, when the combination of ethylene carbonate and diethyl oxalate were used in El- E5, the addition of ethylene carbonate changed the trend of diethyl oxalate's impact on the hydrolysis-resistance properties of the polyurethane samples, particularly E5 showed the best hydrolysis-resistance property.

[0062] It should be understood that after reading the disclosure of the present application, a

person skilled in the art can make many changes and modifications which may also fall into the scope of the present invention as claimed by the following claims.

Claims

1. A polyurethane prepared by reacting the components comprising components A) through G):

A) at least one diisocyanate, polyisocyanate, or isocyanate terminated prepolymer prepared by reacting an isocyanate with a first polyol;

B) at least one second polyol;

C) at least one carbonate;

D) at least one carboxylate having a dissociation constant of its respective carboxylic acid of from 0.5 to 4;

E) optionally at least one catalyst;

F) optionally at least one chain extender; and

G) optionally at least one blowing agent and/or surfactant; wherein at least one of the first polyol and the second polyol is a polyester polyol.

2. The polyurethane of claim 1 , wherein the polyester polyol has a hydroxyl number of from 20 to 280 mgKOH/g and a functionality of from 1 to 3.

3. The polyurethane of claim 1 , wherein the molar ratio of the carbonate groups in the carbonate to the carboxylate groups in the carboxylate is in the range of from 0.85 to 3.40.

4. The polyurethane of claim 1 , wherein the carbonate is cyclic carbonate and/or linear carbonate.

5. The polyurethane of claim 4, wherein the carbonate is selected from the group consisting of ethylene carbonate, propylene carbonate, 1 ,2-butene carbonate, 2,3- butene carbonate, 1 ,2-cyclohexene carbonate, styrene carbonate, and mixtures thereof.

6. The polyurethane of claim 1 , wherein the carboxylate is selected from the group consisting of dimethyl oxalate, diethyl oxalate , dibutyl oxalate, γ-butyro lactone, γ-valerolactone, ε-caprolactone, α,γ-dimethyl butyrolactone, β,γ-dimethyl butyro lactone, γ,γ-dimethyl butyrolactone, a-ethyl-y-methyl butyrolactone, and mixtures thereof.

7. The polyurethane of claim 1 , wherein the two-week hydrolysis resistance of the polyurethane is from 40 to 100% of the retention of tensile strength, determined according to SATRA TM344.

8. A process for preparing a polyurethane comprising the step of reacting

components comprising components A) through G):

A) at least one diisocyanate, polyisocyanate, or isocyanate terminated

prepolymer prepared by reacting an isocyanate with a first polyol;

B) at least one second polyol;

C) at least one carbonate;

E) optionally at least one catalyst;

F) optionally at least one chain extender; and

9. The process of claim 8, wherein the polyester polyol has a hydro xyl number of from 20 to 280 mgKOH/g and a functionality of from 1 to 3.

10. The process of claim 8, wherein the molar ratio of the carbonate groups in the carbonate to the carboxylate groups in the carboxylate is from 0.85 to 3.40.

1 1. The process of claim 8, wherein the carbonate is cyclic carbonate and/or linear carbonate.

12. The process of claim 1 1 , wherein the carbonate is selected from the group

consisting of ethylene carbonate, propylene carbonate, 1 ,2-butene carbonate, 2,3- butene carbonate, 1 ,2-cyclohexene carbonate, styrene carbonate, and mixtures thereof.

13. The process of claim 8, wherein the carboxylate is selected from the group

consisting of dimethyl oxaloacetate, diethyl oxaloacetate, dibutyl oxaloacetate, γ- butyro lactone, γ-valero lactone, ε-caprolactone, α,γ-dimethyl butyro lactone, β,γ- dimethyl butyrolactone, γ,γ-dimethyl butyro lactone, a-ethyl-y-methyl, and butyro lactone.

The process of claim 8, wherein the two-week hydrolysis resistance of the polyurethane is from 40 to 100% of the retention of tensile strength, determined according to SATRA TM344.

15. A polyurethane foam, microcellular elastomer, or elastomer prepared from the polyurethane of claim 1.