Amphiphilic polyester polyol with high wear resistance and low atomization as well as preparation method and application of amphiphilic polyester polyol

Abstract

The invention provides high-wear-resistance and low-atomization amphiphilic polyester polyol as well as a preparation method and application thereof. The high-wear-resistance and low-atomization amphiphilic polyester polyol is prepared from the following raw materials in parts by mole: 100 parts of binary acid / binary anhydride, 60-400 parts of polyol and 3-50 parts of sulfonate-containing alicyclic polyol through esterification and condensation polymerization. The prepared polyester polyol contains sulfonate and an alicyclic ring structure, waterborne polyurethane can be prepared without a waterborne chain extender, and the prepared waterborne polyurethane material has excellent wear resistance and low atomization characteristic, can be applied to industries such as automobile leather and leather finishing agents, and meets the requirements of low VOC and low atomization.

Description

Technical Field

[0001] The invention belongs to the field of polyester polyol preparation, and relates to a highly wear-resistant and low-atomization amphiphilic polyester polyol and a preparation method and application thereof. Background Art

[0002] Polyurethane materials as leather and leather finishing agents have good flexibility, low temperature resistance and fatigue resistance, while water-based polyurethane has the advantages of environmental protection and low VOC compared to traditional solvent polyurethane, so it is widely used in the leather industry.

[0003] At present, leather water-based polyurethane is mainly prepared by reacting polyester polyols or polyether polyols with isocyanates, and then by water-based chain extension (DMPA, etc.), neutralization and other processes. The polyurethane emulsion obtained by this method has poor stability and low solid content, which makes the leather products generally have problems such as poor long-term wear resistance and poor hydrolysis resistance. Patent CN103254414A discloses the use of sodium 5-sulfonate of isophthalic acid to prepare amphiphilic polyester polyols and water-based polyurethanes, without the need for water-based chain extension and improving the stability of polyurethane emulsions, but the use of sodium 5-sulfonate of isophthalic acid to prepare polyester polyols has a slow reaction speed and a long cycle, and the prepared polyurethane material has poor weather resistance; Patent CN117431009 A discloses the introduction of end-vinyl-terminated hydroxyl-terminated silicone oil and single-end acrylate silicone oil in the synthesis process of water-based polyurethane to increase the wear resistance of leather finishing agents, but the preparation method still needs to carry out water-based chain extension, and the production process is relatively cumbersome and the cost is high. At the same time, the automotive and other industries have increasingly higher requirements for the environmental friendliness of polyurethane leather and related products. The precipitation of volatile organic compounds will not only affect people's health, but will also adhere to car windows, front windshields and other locations, affecting the driver's vision and increasing driving risks. Therefore, the industry has put forward higher requirements for the FOG value of polyurethane products.

[0004] Polyester polyols are the raw materials of polyurethanes. They are prepared by esterification and polycondensation of polyacids / anhydrides and polyols. Polyurethanes can be endowed with specific properties by preparing polyester polyols with special structures. Therefore, it is particularly important to prepare an amphiphilic polyester polyol with high wear resistance and low fogging. Summary of the invention

[0005] In view of the problems existing in polyurethane materials in the leather industry, the purpose of the present invention is to provide a highly wear-resistant and low-fogging amphiphilic polyester polyol. The introduction of an aliphatic ring structure containing sulfonate into the polyester polyol can not only simplify the production process of water-based polyurethane, but also greatly improve the wear resistance and heat resistance of the polyurethane leather material.

[0006] Another object of the present invention is to provide a method for preparing the highly wear-resistant, low-fogging amphiphilic polyester polyol. The method has a simple process, and the prepared polyester polyol has a low content of small molecular compounds, thereby reducing the FOG value of the polyurethane material.

[0007] In order to achieve the above object, the present invention adopts the following technical solutions:

[0008] In one aspect, the present invention provides a highly wear-resistant, low-fogging amphiphilic polyester polyol, which is prepared from raw materials comprising the following components:

[0009] Component A: dibasic acid or dibasic acid anhydride, 100 mol parts;

[0010] Component B: polyol, 60-400 mol parts, preferably 80-200 mol parts;

[0011] Component C: sulfonate-containing aliphatic cyclic polyol, 3-50 mole parts, preferably 10-30 mole parts.

[0012] In component A of the highly wear-resistant and low-fogging amphiphilic polyester polyol of the present invention, the dibasic acid is selected from aliphatic dicarboxylic acids having 2 to 20 carbon atoms or aromatic dicarboxylic acids having 6 to 20 carbon atoms; the dibasic acid anhydride is selected from aliphatic acid anhydrides having 4 to 20 carbon atoms or aromatic acid anhydrides having 6 to 20 carbon atoms;

[0013] Preferably, the aliphatic dicarboxylic acid or aromatic dicarboxylic acid is selected from one or more of succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid, furandicarboxylic acid, phthalic acid, isophthalic acid, and terephthalic acid, more preferably succinic acid and / or adipic acid; the aliphatic anhydride or aromatic anhydride is preferably selected from one or more of succinic anhydride, glutaric anhydride, adipic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and phthalic anhydride, more preferably succinic anhydride.

[0014] In component B of the highly wear-resistant and low-fogging amphiphilic polyester polyol of the present invention, the polyol is selected from a polyol having 2 to 20 carbon atoms; preferably, the polyol is selected from one or more of ethylene glycol, 1,4-butanediol, 1,2-propylene glycol, 1,3-propylene glycol, neopentyl glycol, 1,5-pentanediol, 1,2-pentanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,6-hexanediol, butylethylpropylene glycol, diethylpentanediol, trimethylpentanediol, 3-methyl-1,5-pentanediol, diethylene glycol, triethylene glycol, dipropylene glycol, cyclohexanediol, trimethylolpropane, glycerol, and pentaerythritol; more preferably, the polyol is selected from one or more of ethylene glycol, 1,4-butanediol, and neopentyl glycol.

[0015] The component C structure of the highly wear-resistant, low-atomization amphiphilic polyester polyol of the present invention is selected from at least one of formula (I) or formula (II):

[0016]

[0017] Among them, R1 and R2 are independently selected from straight chain or branched alkyl groups with carbon atoms of 0-6, preferably 0 and 1; R3 is a straight chain or branched alkyl group with carbon atoms of 0-6, preferably 1-3; M is selected from Li, Na, K, preferably M is Na.

[0018] When R1 and R2 are selected from alkyl groups with 0 carbon atoms, it means that -OH is directly connected to the six-membered carbon ring. When R3 is an alkyl group with 0 carbon atoms, it means that S is directly connected to the six-membered carbon ring.

[0019] In the present invention, the acid value of the high wear-resistant and low-fogging amphiphilic polyester polyol is 0.01-5.00 mg KOH / g, and the hydroxyl value is 10-200 mg KOH / g; in some preferred embodiments, the acid value of the polyester polyol is 0.05-1.00 mg KOH / g, and the hydroxyl value of the polyester polyol is 30-100 mg KOH / g; in some more preferred embodiments, the acid value of the polyester polyol is 0.05-0.50 mg KOH / g, and the hydroxyl value of the polyester polyol is 50-100 mg KOH / g.

[0020] On the other hand, the present invention also provides a method for preparing a highly wear-resistant and low-atomization amphiphilic polyester polyol, the method comprising the following steps:

[0021] Under the protection of inert gas, component A, component B and component C are mixed, and the temperature is raised to react. A catalyst is optionally added and the reaction is continued until the acid value of the polyester polyol is 0.01-5 mg KOH / g and the hydroxyl value is 10-200 mg KOH / g. The reaction is then completed.

[0022] In a specific embodiment, the components A, B, and C can be mixed and then heated to react in stages, such as reacting at 140-160° C. for 0.5 h-1.5 h; then heating to 170-180° C. for 0.5 h-1.5 h, and finally, raising the temperature to 210-230° C.

[0023] Preferably, after optionally adding a catalyst, the reaction is continued at 210-230° C. under vacuum until the acid value and the hydroxyl value meet the requirements.

[0024] Preferably, the vacuum degree is -0.01 to -0.1 MPa.

[0025] Preferably, after the reaction is completed, the product is subjected to a devolatilization treatment, which may be carried out by a commonly used devolatilization method in the prior art, such as evaporation, in order to remove some small molecular substances.

[0026] In a specific embodiment, the evaporation and devolatilization is specifically to transport the product to a thin film evaporator, control the temperature to 80-120° C., the vacuum degree to -0.09 to -0.1 MPa, and perform the devolatilization treatment for 0.5-5 h to obtain the polyester polyol.

[0027] In the method for preparing polyester polyol provided by the present invention, based on the total mass of the component A, the component B and the component C, the amount of the catalyst used is 0-500 ppm, preferably 40-300 ppm.

[0028] In some specific embodiments, the catalyst is selected from one or more of a titanium catalyst, a tin catalyst or an antimony catalyst; preferably, the titanium catalyst is selected from one or more of n-butyl titanate, tetraisopropyl titanate or titanium dioxide; the tin catalyst is selected from one or more of dibutyltin dilaurate, stannous octoate or stannous chloride; the antimony catalyst is selected from one or more of antimony acetate, antimony trioxide or ethylene glycol antimony; in some preferred embodiments, the catalyst uses a titanium catalyst, more preferably n-butyl titanate or tetraisopropyl titanate.

[0029] The present invention also provides an aqueous polyurethane for leather, wherein the aqueous polyurethane for leather is obtained by reacting components comprising the following raw materials: (mass percentage)

[0030] High wear resistance, low atomization amphiphilic polyester polyol: 70-89wt%,

[0031] Diisocyanate monomer: 9-29wt%,

[0032] Chain extender: 0.5-3wt%,

[0033] Catalyst: 0.02-0.05wt%.

[0034] In one embodiment, the diisocyanate monomer is one or more of toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), isophorone diisocyanate (IPDI), hexamethylene diisocyanate (HDI), hexacyclohexylmethane diisocyanate (HMDI), naphthalene diisocyanate (NDI), p-phenylene diisocyanate (PPDI), 1,4-cyclohexane diisocyanate (CHDI), xylylene diisocyanate (XDI), and cyclohexane dimethylene diisocyanate (HXDI). Preferably, the diisocyanate monomer is isophorone diisocyanate (IPDI).

[0035] In one embodiment, the chain extender is one or more of ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, and 1,6-hexanediol. Preferably, the chain extender is one or more of 1,4-butanediol, neopentyl glycol, and 1,6-hexanediol.

[0036] In some specific embodiments, the catalyst is selected from tertiary amines and / or organometallics, preferably selected from one or more of triethylenediamine, N,N-dimethylcyclohexylamine, dibutyltin dilaurate, stannous octoate, and bismuth carboxylate, more preferably stannous octoate and / or dibutyltin dilaurate.

[0037] The preparation method of water-based polyurethane for leather can refer to the conventional methods in the art, for example, it can be: 1) adding the high wear-resistant, low-atomization polyester polyol, diisocyanate monomer, chain extender and catalyst described in the present invention into a reactor, reacting under the protection of an inert gas (such as nitrogen) until the NCO content reaches the theoretical value, adding an organic solvent, adjusting the viscosity of the system, cooling, and discharging to obtain a polyurethane resin; 2) adding the polyurethane resin into an emulsifying kettle, slowly adding deionized water according to a solid content of 30-60%, stirring for emulsification, and removing the organic solvent by reduced pressure distillation to obtain a water-based polyurethane emulsion for leather.

[0038] Specifically, the reaction temperature in step 1) can be 70-80° C., and the reaction time can be 2-3 h, which can be adjusted by those skilled in the art according to actual production conditions.

[0039] The positive effects of the present invention are:

[0040] (1) The highly wear-resistant and low-fogging polyester polyol of the present invention contains a sulfonate-type aliphatic ring structure, which not only gives the polyester polyol amphiphilic properties and simplifies the waterborne polyurethane synthesis process, but also greatly improves the wear resistance of the polyurethane material and prolongs the service life of the material;

[0041] (2) The highly wear-resistant and low-fogging polyester polyol of the present invention imparts a low FOG value to the polyurethane material, satisfying its application in the automotive interior decoration industry. DETAILED DESCRIPTION

[0042] In order to better understand the technical solution of the present invention, the content of the present invention is further described below in conjunction with the embodiments, but the content of the present invention is not limited to the following embodiments.

[0043] The main raw materials used in the following examples and comparative examples are all commercial chemicals. 3,4-dihydroxy-sodium cyclohexaneethyl sulfonate (cas number 354820-68-1) and 3,4-dimethanol-sodium cyclohexaneethyl sulfonate were purchased from Aurora; 1,4-butanediol, neopentyl glycol, ethylene glycol, 1,3-propylene glycol, adipic acid and terephthalic acid, catalyst stannous octoate, etc. are all commercially available raw materials; IPDI comes from Wanhua Chemical.

[0044] The product performance in the embodiments and comparative examples of the present invention was measured using the following method:

[0045] Determination of acid value: refer to chemical industry standard HG / T 2708-1995;

[0046] Determination of hydroxyl value: refer to chemical industry standard HG / T 2709-1995;

[0047] Abrasion resistance determination: refer to international standard ISO 4649-2017;

[0048] FOG value determination: refer to automotive industry standard VDA278.

[0049] Emulsion stability: The prepared waterborne polyurethane was stored at room temperature and its state was observed.

[0050] The molecular weight is calculated based on the hydroxyl value. For example, the molecular weight of a difunctional polyester polyol is calculated as follows: molecular weight = 112200 / hydroxyl value.

[0051] Example 1

[0052] 9.91 kg of 1,4-butanediol, 7.42 kg of sodium 3,4-dihydroxy-cyclohexaneethylsulfonate and 14.61 kg of adipic acid were mixed evenly, and the temperature was raised to 150°C and kept constant for 1.0 h; the temperature was further raised to 175°C and kept constant for 1.0 h; finally, the temperature was raised to 220°C, and when the acid value was less than 10 mg KOH / g, 1.24 g of tetraisopropyl titanate was added, and the vacuum was turned on to -0.095 MPa to remove the reaction product water and excess diol. When the acid value was 0.05 mg KOH / g and the hydroxyl value was 59.5 mg KOH / g, the product was transported to a thin film evaporator at 90°C and a vacuum degree of -0.095 MPa. After devolatilization treatment for 2.5 h, a highly wear-resistant and low-atomizing polyester polyol A with an acid value of 0.05 mg KOH / g, a hydroxyl value of 56.1 mg KOH / g and an average molecular weight of 2000 g / mol was obtained.

[0053] Example 2

[0054] 18.62 kg of ethylene glycol, 3.71 kg of sodium 3,4-dihydroxy-cyclohexaneethyl sulfonate and 11.81 kg of succinic acid were mixed evenly, and the temperature was raised to 150°C and kept constant for 1.5 hours; the temperature was further raised to 170°C and the reaction was kept constant for 0.75 hours; finally, the temperature was raised to 210°C, and when the acid value was less than 10 mg KOH / g, 3.36 g of tetraisopropyl titanate was added, and the vacuum was turned on to -0.090 MPa to remove the reaction product water and excess diol. When the acid value was 0.10 mg KOH / g and the hydroxyl value was 48.9 mg KOH / g, the product was transported to a thin film evaporator at a temperature of 90°C and a vacuum degree of -0.090 MPa. After devolatilization treatment for 4 hours, a highly wear-resistant and low-atomizing polyester polyol B with an acid value of 0.10 mg KOH / g, a hydroxyl value of 44.88 mg KOH / g and an average molecular weight of 2500 g / mol was obtained.

[0055] Example 3

[0056] 6.25 kg of neopentyl glycol, 5.51 kg of 3,4-dimethanol-sodium cyclohexaneethylsulfonate and 10.01 kg of succinic anhydride were mixed evenly, and the temperature was raised to 140°C and kept constant for 1.5 hours; the temperature was further raised to 180°C and the reaction was kept constant for 0.5 hours; finally, the temperature was raised to 230°C, and when the acid value was less than 15 mg KOH / g, 4.22 g of n-butyl titanate was added, and the vacuum was opened to -0.100 MPa to remove the reaction product water and excess diol. When the acid value was 2.50 mg KOH / g and the hydroxyl value was 42.50 mg KOH / g, the product was transported to a thin film evaporator at a temperature of 100°C and a vacuum degree of -0.09 MPa. The product was devolatilized for 0.5 hours to obtain a highly wear-resistant and low-atomizing polyester polyol C having an acid value of 2.50 mg KOH / g, a hydroxyl value of 37.40 mg KOH / g and an average molecular weight of 3000 g / mol.

[0057] Example 4

[0058] 36.05 kg 1,4-butanediol, 1.38 kg 3,4-dimethanol-sodium cyclohexaneethylsulfonate and 14.61 kg adipic acid were mixed evenly, and the temperature was raised to 160°C and kept constant for 0.5 h; the temperature was further raised to 180°C and kept constant for 1.5 h; finally, the temperature was raised to 220°C, and when the acid value was less than 15 mg KOH / g, 15.56 g n-butyl titanate was added, and the vacuum was turned on to -0.095 MPa to remove the reaction product water and excess diol. When the acid value was 5 mg KOH / g and the hydroxyl value was 115 mg KOH / g, the product was transported to a thin film evaporator at a temperature of 120°C and a vacuum degree of -0.095 MPa. After devolatilization for 2 h, a highly wear-resistant and low-atomizing polyester polyol D with an acid value of 5 mg KOH / g, a hydroxyl value of 112 mg KOH / g and an average molecular weight of 1000 g / mol was obtained.

[0059] Example 5

[0060] 47.27 kg 1,6-hexanediol, 1.24 kg 3,4-dimethanol-sodium cyclohexaneethylsulfonate and 14.61 kg adipic acid were mixed evenly, and the temperature was raised to 160°C and kept constant for 0.5 h; the temperature was further raised to 180°C and kept constant for 1.5 h; finally, the temperature was raised to 220°C, and when the acid value was less than 15 mg KOH / g, 18.93 g stannous octoate was added, and the vacuum was turned on to -0.095 MPa to remove the reaction product water and excess diol. When the acid value was 0.5 mg KOH / g and the hydroxyl value was 116 mg KOH / g, the product was transported to a thin film evaporator at 90°C and a vacuum degree of -0.095 MPa. After devolatilization for 5 h, a highly wear-resistant and low-atomizing polyester polyol E with an acid value of 5 mg KOH / g, a hydroxyl value of 112 mg KOH / g and an average molecular weight of 1000 g / mol was obtained.

[0061] Comparative Example 1

[0062] 9.91 kg 1,4-butanediol and 14.61 kg adipic acid were mixed evenly, and the temperature was raised to 150°C and kept constant for 1.0 h; the temperature was further raised to 175°C and the reaction was kept constant for 1.0 h; finally, the temperature was raised to 220°C, and when the acid value was less than 10 mg KOH / g, 0.98 g tetraisopropyl titanate was added, and the vacuum was opened to -0.095 MPa to remove the reaction product water and excess diol. When the acid value was 0.05 mg KOH / g and the hydroxyl value was 59.2 mg KOH / g, the product was transported to a thin film evaporator at 90°C and a vacuum degree of -0.095 MPa. After devolatilization treatment for 2.5 h, polyester polyol F was obtained, with an acid value of 0.05 mg KOH / g, a hydroxyl value of 56 mg KOH / g, and an average molecular weight of 2000 g / mol.

[0063] Comparative Example 2

[0064] 9.91 kg of 1,4-butanediol, 7.42 kg of sodium 3,4-dihydroxy-cyclohexaneethylsulfonate and 14.61 kg of adipic acid were mixed evenly, and the temperature was raised to 150°C and kept constant for 1.0 h; the temperature was further raised to 175°C and the reaction was kept constant for 1.0 h; finally, the temperature was raised to 220°C, and when the acid value was less than 10 mg KOH / g, 1.24 g of tetraisopropyl titanate was added, and the vacuum was opened to -0.095 MPa to remove the reaction product water and excess diols. When the acid value reached 0.05 mg KOH / g and the hydroxyl value reached 56 mg KOH / g, polyester polyol G with an average molecular weight of 2000 g / mol was obtained.

[0065] Application Examples 1-7

[0066] Application Examples 1-7 are the preparation of waterborne polyurethanes PUD-A to PUD-G.

[0067] According to the following formula table, water-based polyurethane for leather can be prepared according to the following steps: 1) The highly wear-resistant, low-atomizing polyester polyol, diisocyanate monomer (IPDI), chain extender and catalyst (stannous octoate T9) described in the present invention are added into a reaction kettle according to the theoretical calculated amount, protected by nitrogen, reacted at 80°C for 2.5 hours until the NCO content reaches the theoretical value, an organic solvent is added, the viscosity of the system is adjusted, the temperature is lowered, and the material is discharged; 2) The polyurethane resin is added into an emulsifying kettle, deionized water is slowly added, emulsified at a speed of 2000r / min, and the organic solvent is removed by reduced pressure distillation to obtain a water-based polyurethane emulsion for leather.

[0068] Table 1 Synthesis formula of polyurethane elastomer in application examples 1-7 (mass fraction)

[0069]

[0070] Performance Testing

[0071] The properties of waterborne polyurethane emulsion and leather material prepared by high wear-resistant and low-fogging polyester polyol were measured according to the aforementioned method. The results are shown in the following table.

[0072] As can be seen from Table 2, since the polyester polyol F does not contain the sulfonate-containing alicyclic polyol of component C, the polyester polyol F cannot be used to prepare waterborne polyurethane without adding an aqueous chain extender, while the polyester polyols AE prepared using Examples 1-5 can directly prepare waterborne polyurethane, which shows that the high wear-resistant and low-fogging polyester polyol of the present invention has amphiphilicity, and waterborne polyurethane can be prepared without aqueous chain extension, and the prepared polyurethane emulsion has excellent stability; the wear resistance test results show that the waterborne polyurethane leather material prepared using the high wear-resistant and low-fogging polyester polyol of the present invention has excellent wear resistance, which is mainly because the introduction of the alicyclic ring can improve the wear resistance of the material; and the FOG value shows that the use of the low-fogging polyester polyol of the present invention after devolatilization can effectively reduce the FOG value of the waterborne polyurethane material, meeting the use requirements of the automotive interior industry.

[0073] Table 2 Comparison of properties of waterborne polyurethane prepared by polyester polyols in the examples and comparative examples

[0074]

[0075]

Claims

1. A highly wear-resistant, low-atomization amphiphilic polyester polyol, which is prepared from raw materials comprising the following components: Component A: dibasic acid or dibasic acid anhydride, 100 mol parts; Component B: polyol, 60-400 mol parts, preferably 80-200 mol parts; Component C: sulfonate-containing aliphatic cyclic polyol, 3-50 mole parts, preferably 10-30 mole parts.

2. The polyester polyol according to claim 1, characterized in that In component A, the dibasic acid is selected from aliphatic dicarboxylic acids having 2-20 carbon atoms or aromatic dicarboxylic acids having 6-20 carbon atoms, and the dibasic acid anhydride is selected from aliphatic acid anhydrides having 4-20 carbon atoms or aromatic acid anhydrides having 6-20 carbon atoms; preferably, the aliphatic dicarboxylic acids and aromatic dicarboxylic acids are selected from one or more of succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, furandicarboxylic acid, phthalic acid, isophthalic acid, and terephthalic acid; preferably, the aliphatic acid anhydride and aromatic acid anhydride are selected from one or more of succinic anhydride, glutaric anhydride, adipic anhydride, maleic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, and phthalic anhydride.

3. The polyester polyol according to claim 1 or 2, characterized in that The component B polyol is selected from polyols having 2 to 20 carbon atoms; preferably, the polyol is selected from one or more of ethylene glycol, 1,4-butanediol, 1,2-propylene glycol, 1,3-propylene glycol, neopentyl glycol, 1,5-pentanediol, 1,2-pentanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,6-hexanediol, butylethylpropylene glycol, diethylpentanediol, trimethylpentanediol, 3-methyl-1,5-pentanediol, diethylene glycol, triethylene glycol, dipropylene glycol, cyclohexanediol, trimethylolpropane, glycerol, and pentaerythritol; more preferably, the polyol is selected from one or more of ethylene glycol, 1,4-butanediol, and neopentyl glycol.

4. The polyester polyol according to any one of claims 1 to 3, characterized in that The structure of component C is selected from at least one of formula (I) or formula (II): Among them, R1 and R2 are independently selected from straight chain or branched alkyl groups with carbon atoms of 0-6, preferably 0 or 1; R3 is a straight chain or branched alkyl group with carbon atoms of 0-6, preferably 1-3; M is selected from Li, Na, and K.

5. A method for preparing a polyester polyol as claimed in any one of claims 1 to 4, characterized in that: The method comprises the following steps: Under the protection of inert gas, component A, component B and component C are mixed, and the temperature is raised to react. A catalyst is optionally added and the reaction is continued until the acid value of the polyester polyol is 0.01-5 mg KOH / g and the hydroxyl value is 10-200 mg KOH / g. The reaction is then completed.

6. The preparation method according to claim 5, characterized in that: The temperature reaction is to react at 140-160°C for 0.5h-1.5h, then heat to 170-180°C for 0.5h-1.5h, and finally, raise the temperature to 210-230°C; preferably, after the temperature is raised to 210-230°C, a catalyst is added, and the reaction is continued until the acid value of the system is 0.01-5mg KOH / g and the hydroxyl value is 10-200mgKOH / g, and the reaction is terminated.

7. The preparation method according to claim 5 or 6, characterized in that: The method further comprises a devolatilization step: when the acid value and hydroxyl value requirements are met, the product temperature is controlled to be 80-120° C., the vacuum degree is -0.09 to -0.1 MPa, and the devolatilization is performed for 0.5 to 5 hours to obtain the polyester polyol.

8. The preparation method according to any one of claims 5 to 7, characterized in that: Based on the total mass of the component A, the component B and the component C, the amount of the catalyst used is 0-500 ppm, preferably 40-300 ppm.

9. The preparation method according to any one of claims 5 to 8, characterized in that: The catalyst is selected from one or more of a titanium catalyst, a tin catalyst or an antimony catalyst; preferably, the titanium catalyst is selected from n-butyl titanate, tetraisopropyl titanate or titanium dioxide, the tin catalyst is selected from dibutyltin dilaurate, stannous octoate or stannous chloride, and the antimony catalyst is selected from antimony acetate, antimony trioxide or antimony glycol; the catalyst is more preferably n-butyl titanate or tetraisopropyl titanate.

10. A water-based polyurethane for leather, characterized in that: The aqueous polyurethane for leather is obtained by reacting components comprising the following raw materials: High wear resistance, low atomization amphiphilic polyester polyol: 70-89wt%, Diisocyanate monomer: 9-29wt%, Chain extender: 0.5-3wt%, Catalyst: 0.02-0.05wt%; Preferably, The diisocyanate monomer is one or more of toluene diisocyanate, diphenylmethane diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, hexacyclohexylmethane diisocyanate, naphthalene diisocyanate, p-phenylene diisocyanate, 1,4-cyclohexane diisocyanate, xylylene diisocyanate, and cyclohexane dimethylene diisocyanate; And / or: the chain extender is one or more of ethylene glycol, 1,3-propylene glycol, 1,2-propylene glycol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,4-cyclohexanedimethanol, neopentyl glycol, and 1,6-hexanediol; And / or: the catalyst is selected from tertiary amines and organometallics, preferably selected from one or more of triethylenediamine, N,N-dimethylcyclohexylamine, dibutyltin dilaurate, stannous octoate, and bismuth carboxylate, more preferably stannous octoate and / or dibutyltin dilaurate.

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