Biobased isosorbide polyurethane polyols and methods for making the same

Abstract

The application discloses a kind of bio-based isosorbide polyurethane polyols and preparation method thereof, belong to the technical field of bio-based polymer materials.The present application takes bio-based isosorbide as core raw material, combined with vegetable oil glycol monomer, respectively with alkylene oxide, dimer fatty acid, dimethyl carbonate and other monomers are polymerized to prepare polyether ester polyol, polyester polyol, polycarbonate polyol.Through accurate control isosorbide and the copolymerization ratio of vegetable oil glycol, special catalyst system, ladder temperature control, gradient vacuum condensation process, three kinds of bio-based polyols are prepared, with light color, narrow molecular weight distribution, functional accuracy controllable characteristics.The bio-based polyurethane material prepared therefrom has high transparency, high rigidity, high heat resistance, hydrolysis resistance, low yellowing, wear resistance and other comprehensive performance.Polyol bio-based content 38%-95%, widely used in polyurethane rigid insulation material, weather-resistant waterproof coating, casting elastomer, artificial leather slurry, hot melt adhesive, optical TPU film, medical polyurethane products and other fields.

Description

Technical Field

[0001] This invention belongs to the field of bio-based polymer materials technology, and relates to a class of isosorbide-based polyurethane polyols with bio-based isosorbide as the core raw material and their preparation method. Background Technology

[0002] Polyurethane (PU) materials, with their adjustable mechanical properties, simple molding processes, and excellent adhesion, are widely used in insulation materials, elastomers, adhesives, coatings, and leather. However, polyols are the core raw materials that determine the final performance of polyurethane. Currently, they are primarily dependent on petrochemical raw materials, resulting in a high carbon footprint, which does not align with current policies promoting bio-based and low-carbon chemical production. Furthermore, polyols suffer from drawbacks such as low heat distortion temperature, insufficient rigidity, susceptibility to creep during long-term outdoor use, and poor hydrolytic stability. Their thermal stability, dimensional stability, and light transmittance are insufficient to meet the demands of high-end optical and automotive weather-resistant materials.

[0003] Isosorbide is a biomass-derived, fully bio-based diol. When combined with aliphatic flexible segments, it can be used to prepare a novel class of polyurethane polyols, leading to a class of polyurethane products with superior performance. Its molecule contains a bicyclic rigid lactone structure, which can significantly improve the polymer's heat resistance, rigidity, and transparency. However, existing synthesis processes face industrial challenges such as easy oxidation and discoloration of isosorbide at high temperatures, decomposition, wide polymer molecular weight distribution, high catalyst residue, and difficulty in controlling the hydroxyl value of the product. These limitations prevent it from simultaneously meeting the diverse polyurethane needs of applications such as foams, elastomers, and optical materials. Therefore, improvements to its preparation process are urgently needed to meet the demands of industrial production. Summary of the Invention

[0004] Based on the current state of technology, the purpose of this invention is to provide a series of terminal hydroxyl polyol products with isosorbide as the core, and to provide an easy-to-industrialize preparation method for each type of product, thereby improving the product quality of isosorbide.

[0005] To achieve the objectives of this invention, by adjusting the proportion of copolydiol and the molar percentage of isosorbide, the catalytic system and the reaction process, three types of polyols suitable for rigid foams, elastomers, weather-resistant coatings and weather-resistant optical materials are obtained, thereby improving the performance of polyurethane products.

[0006] In a first aspect, the present invention provides a class of bio-based polyether ester polyols and their preparation methods.

[0007] The aforementioned bio-based polyether ester polyol is a mixture containing copolymers of the following repeating structural units:

[0008] and Where m is a natural number from 1 to 10, n is a natural number from 1 to 10, and R is the fatty chain of vegetable oil diol, with the fatty chain being a C3-21 hydrocarbon group.

[0009] Its preparation method: It is prepared by first ring-opening polymerization of propylene oxide (PO) with isosorbide and vegetable oil diol as initiators, followed by end-capping with ethylene oxide (EO). The mass percentage of isosorbide in the initiator is 50%-80%.

[0010] The specific steps of this method include: 1.1 Pretreatment before reaction: The initiator is dehydrated under vacuum at 100-120℃ to remove water from the system, and the water content of the system is controlled to be ≤100ppm.

[0011] 1.2 Catalytic ring-opening polymerization: Add KOH or DMC bimetallic cyanide (zinc hexacyanocobaltate) as a catalyst to the vacuum-dried system. The catalyst addition amount is 0.01%-0.2% of the total mass of the initiator. Then, raise the temperature to 120-135℃ and continuously and slowly add PO monomer, EO monomer, or a mixture of both dropwise to the system, controlling the pressure within the system to ≤0.4MPa. Whether EO end-capping is required when adding PO monomer depends on the product performance; for example, EO end-capping is required when producing high-performance flexible polyurethane foam. After the monomer is added, maintain the temperature and allow it to mature until the pressure within the system stabilizes.

[0012] 1.3 Post-processing and refining: Control the system temperature to 120℃, remove residual propylene oxide monomer under vacuum, and remove moisture under vacuum until the moisture content is ≤0.03%; reduce the system temperature to 70-90℃, neutralize with phosphoric acid, and if KOH is used as a catalyst, desalination by adsorption and filtration with magnesium aluminum silicate is also required; raise the system temperature to 110-120℃ and add antioxidant 1076 (β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate octadecyl alcohol ester), the amount added is 0.05%-0.1% of the total product mass, cool down and discharge to obtain the final product.

[0013] Secondly, the present invention provides a class of bio-based polyester polyols and their preparation methods.

[0014] The aforementioned bio-based polyester polyol is a copolymer containing the following repeating structural units: Where m is a natural number from 1 to 10, n is a natural number from 1 to 10, and R is the fatty chain of vegetable oil diol, with the fatty chain being a C3-21 hydrocarbon group.

[0015] Its preparation method: It is prepared by reacting isosorbide and vegetable oil diol with dimer fatty acids. The molar ratio of isosorbide to vegetable oil diol is 60-90:40-10, and the molar ratio of vegetable oil diol to dimer fatty acids is 1.05-1.2:1.

[0016] The specific steps of this method include: 2.1 Atmospheric pressure esterification: Isosorbide, vegetable oil diol, dimer fatty acid, catalyst, and stabilizer are added to the reaction system equipped with a water separator. Under inert nitrogen protection, the temperature is gradually increased in the range of 160-200℃ to esterify and separate water. The reaction is carried out until the acid value of the system is ≤30mgKOH / g.

[0017] The reaction gradient heating is characterized by the following: the reaction system is first heated to 160-170℃ and reacted for 0.5-1.5 h; then heated to 180-185℃ and reacted for 1-1.5 h; and finally heated to 200℃ and reacted for 0.5-1 h.

[0018] 2.2 Gradient vacuum polycondensation: The system is heated to 210-230℃, and the vacuum level is gradually increased to ≤50Pa. The polycondensation reaction continues, and the acid value and hydroxyl value are monitored online in real time to meet the standard requirements.

[0019] The gradient vacuum polycondensation is characterized by gradually reducing the pressure of the reaction system to ≤50 Pa at a rate of two-thirds every 20 minutes. 2.3 Refined discharge: After the system temperature is reduced to room temperature, nitrogen is used to break the vacuum, and impurities are removed by filtration to obtain a light yellow transparent polyester polyol.

[0020] The catalyst is tetrabutyl titanate or monobutyltin oxide, and the amount added is 0.01%-0.05% of the total mass of the raw materials.

[0021] The stabilizer is an antioxidant 1010 (pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate]) and a phosphite in a mass ratio of 2:1, with the total addition amount being 0.03%-0.1% of the total mass of the raw materials.

[0022] Thirdly, the present invention provides a class of bio-based polycarbonate polyols and their preparation methods.

[0023] The aforementioned bio-based polycarbonate polyol is a copolymer containing the following repeating structural units: Where m is a natural number from 1 to 10, n is a natural number from 1 to 10, and R is the fatty chain of vegetable oil diol, with the fatty chain being a C3-21 hydrocarbon group.

[0024] Its preparation method: It is produced by melt transesterification polycondensation of isosorbide and vegetable oil diol with dimethyl carbonate (DMC).

[0025] The specific steps of this method include: 3.1 Atmospheric pressure pre-esterification: Isosorbide, vegetable oil diol, dimethyl carbonate and catalyst are added to the vacuum reaction system and refluxed at 150-160℃ under nitrogen protection to continuously distill off methanol byproducts. The system is then heated to 180℃ to remove excess DMC monomers, yielding hydroxyl-terminated carbonate oligomers.

[0026] 3.2 High-temperature high-vacuum polycondensation: The system is heated to 220-240℃, and the vacuum degree is controlled to ≤50Pa. Polycondensation is carried out to continuously remove small molecule by-products. The viscosity and hydroxyl value of the system are tested until they meet the standards.

[0027] 3.3 Refined discharge: After the system temperature is reduced to room temperature, nitrogen is used to break the vacuum, and the mixture is filtered to remove impurities, resulting in a light yellow transparent polycarbonate polyol.

[0028] The catalyst is a sodium iodide-imidazolium sodium complex or a zinc-cobalt bimetallic DMC catalyst. More specifically, the sodium iodide-imidazolium sodium complex is preferably prepared by mixing sodium iodide and sodium iodide in a mass ratio of 2:1 to 6:1. The zinc-cobalt bimetallic DMC catalyst is selected from the bimetallic DMC catalyst obtained by complexing zinc hexacyanocobalaminate with tert-butanol. The addition amount is 20-500 ppm of the total mass of the diol.

[0029] The above-mentioned vegetable oil diols are derived from vegetable oils such as coconut oil, soybean oil, and palm oil.

[0030] Fourthly, this invention provides a class of bio-based polyurethane materials and a method for preparing the same, comprising: Prepared by addition polymerization using any one or more polyols prepared above and one or more isocyanate monomers MDI, TDI, HDI, and IPDI as raw materials.

[0031] The innovation of this invention lies in the following: by precisely controlling the copolymerization ratio of isosorbide and vegetable oil diol, using a dedicated catalytic system, step-controlled temperature, and gradient vacuum condensation processes, three types of bio-based polyols are prepared, exhibiting characteristics such as light color, narrow molecular weight distribution, and precisely controllable functionality. The bio-based polyurethane materials prepared in this way possess comprehensive properties including high transparency, high rigidity, high heat resistance, hydrolysis resistance, low yellowing, and wear resistance.

[0032] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. Introducing bio-based isosorbide bicyclic structure and vegetable oil diol into the molecular backbone can simultaneously improve the heat resistance, rigidity, ductility, light transmittance and creep resistance of polyurethane products. 2. This invention is a set of polyols covering the three major categories of polyols used in the production of polyurethane: polyether ester polyols, polyester polyols, and polycarbonate polyols, and has strong versatility. 3. The preparation system is equipped with a dedicated catalytic and temperature control process to obtain DMC narrow-distribution polyether ester polyol, step-vacuum low-color-change polyester polyol, and transesterification polycondensation low-color-change polycarbonate polyol. The temperature control process solves the problem of yellowing due to high-temperature decomposition of isosorbide. The bio-based content of the polyol is 38%-95%, which is conducive to improving the quality of polyurethane products. It is green and environmentally friendly and can realize industrial production of tens of thousands of tons. It can be widely used in polyurethane rigid insulation materials, weather-resistant and waterproof coatings, cast elastomers, artificial leather slurries, hot melt adhesives, optical TPU films, medical polyurethane products and other fields. Detailed Implementation

[0033] To provide a clearer understanding of the technical features, objectives, and effects of this invention, the following embodiments are provided: The following embodiments of the present invention are only used to explain the technical solution of the present invention and are not intended to limit the scope of protection. The production equipment consists of a conventional high-pressure polyether reactor, an esterification and water separation reactor, and a high-vacuum polycondensation reactor. Example 1

[0034] Pretreatment of the reaction: Check the airtightness of the apparatus, add 265.1g of isosorbide and 66.3g of coconut oil diol as initiators, and dehydrate the initiators under vacuum at 110°C to remove water from the system.

[0035] Catalytic ring-opening polymerization: 1.5 g of KOH catalyst was added to the vacuum-dried system. The temperature was then raised to 125 °C, and 1668.6 g of PO monomer was continuously and slowly added dropwise, controlling the pressure within the system to ≤0.4 MPa. After the monomer was added, the system was allowed to mature at this temperature for 2 hours until the pressure within the system stabilized.

[0036] Post-processing refining: The system temperature was controlled at 120℃, and residual propylene oxide monomer was removed under vacuum for 1 hour. Moisture was then removed under vacuum until the moisture content was 0.03%. The system temperature was lowered to 80℃, and 2.6g of phosphoric acid was added for neutralization for 30 minutes. Subsequently, 1.6g of magnesium silicate adsorbent was added and stirred for 15 minutes before filtration. Finally, the system temperature was raised to 115℃, and 1g of antioxidant 1076 was added. The mixture was then cooled and discharged to obtain the final product. The main technical indicators of the obtained product are: hydroxyl value = 110mgKOH / g, corresponding to a molecular weight of 1000; acid value = 0.05mgKOH / g; moisture content = 0.02%; potassium ion content = 3ppm; unsaturation degree = 0.02mol / kg; color (APHA) = 45; viscosity (25℃) = 302.6mPa·s. Example 2

[0037] Pretreatment of the reaction: Check the airtightness of the apparatus, add 111.6 g of isosorbide and 74.4 g of coconut oil diol as initiators, and dehydrate the initiators under vacuum at 110 °C to remove water from the system.

[0038] Catalytic ring-opening polymerization: 2.0 g of KOH catalyst was added to the vacuum-dried system. The temperature was then raised to 130 °C, and 1814 g of PO monomer was continuously and slowly added dropwise, maintaining the pressure within the system at ≤0.4 MPa. After the monomer was added, the system was allowed to mature at this temperature for 4 hours until the pressure within the system stabilized.

[0039] Post-processing and refining: The system temperature was controlled at 120℃, and residual propylene oxide monomer was removed under vacuum for 1 hour. Moisture was then removed under vacuum until the moisture content was 0.02%. The system temperature was lowered to 90℃, and 3.5g of phosphoric acid was added for neutralization for 30 minutes. Subsequently, 1.6g of magnesium silicate adsorbent was added and stirred for 15 minutes before filtration. Finally, the system temperature was raised to 115℃, and 1g of antioxidant 1076 was added. The mixture was then cooled and discharged to obtain the final product. The main technical indicators of the obtained product are: hydroxyl value = 58mgKOH / g, corresponding molecular weight 2000, acid value = 0.02mgKOH / g, moisture = 0.03%, potassium ion = 4ppm, unsaturation = 0.03mol / kg, color (APHA) = 40, and viscosity (25℃) = 386.6mPa·s. Example 3

[0040] Esterification was performed under normal pressure. 144.54 g of isosorbide, 30.14 g of coconut oil diol, 561 g of dimer fatty acid, 0.15 g of tetrabutyl titanate catalyst, 0.1 g of antioxidant 1010, and 0.05 g of phosphite ester stabilizer were added to a reaction system equipped with a water separator. Under inert nitrogen protection, the temperature was raised to 165 °C and held for 0.5 h; then raised to 180 °C and reacted for 1 h; finally, the temperature was raised to 200 °C and reacted for 1 h. The reaction was carried out until the acid value of the system reached 12 mg KOH / g.

[0041] Gradient vacuum polycondensation was performed, with the system temperature raised to 230℃. The pressure of the reaction system was gradually reduced to 50 Pa at a rate of two-thirds every 20 minutes. The polycondensation reaction was continued, and the acid value was monitored online in real time to ensure it met the standard requirements of 0.5 mgKOH / g and hydroxyl value of 114 mgKOH / g (corresponding to a molecular weight of 1000).

[0042] After refining and discharging, the system temperature is lowered to room temperature, and nitrogen is used to break the vacuum. The mixture is then filtered to remove impurities, yielding a light yellow transparent polyester polyol. Example 4

[0043] Esterification was performed under normal pressure. 96.36 g of isosorbide, 120.56 g of coconut oil diol, 561 g of dimer fatty acid, 0.31 g of monobutyltin oxide catalyst, 0.2 g of antioxidant 1010, and 0.1 g of phosphite ester stabilizer were added to a reaction system equipped with a water separator. Under inert nitrogen protection, the temperature was raised to 170℃ and held for 1 h; then raised to 185℃ and reacted for 1.5 h; finally, the temperature was raised to 200℃ and reacted for 1 h. The reaction was continued until the acid value of the system reached 8 mg KOH / g.

[0044] Gradient vacuum polycondensation was performed, with the system temperature raised to 225℃. The pressure of the reaction system was gradually reduced to 50 Pa at a rate of two-thirds every 20 minutes. The polycondensation reaction was continued, and the acid value was monitored online in real time to ensure it met the standard requirements of 0.5 mgKOH / g and hydroxyl value of 54 mgKOH / g (corresponding to a molecular weight of 2000).

[0045] After refining and discharging, the system temperature is lowered to room temperature, and nitrogen is used to break the vacuum. The mixture is then filtered to remove impurities, yielding a light yellow transparent polyester polyol. Example 5

[0046] Under normal pressure, pre-esterification was performed by adding 289.08 g of isosorbide, 60.28 g of coconut oil diol, 180 g of dimethyl carbonate, and 0.070 g of zinc-cobalt bimetallic DMC catalyst to a high-vacuum reaction system. The system was refluxed at 150°C for 1 hour under nitrogen protection, continuously distilling off methanol byproducts. The system was then heated to 180°C to remove excess DMC monomers, yielding hydroxyl-terminated carbonate oligomers. The zinc-cobalt bimetallic DMC catalyst was selected from a bimetallic DMC catalyst obtained by complexing zinc hexacyanocobalaminate with tert-butanol.

[0047] High-temperature, high-vacuum polycondensation was performed by heating the system to 220°C, controlling the vacuum level to be less than 50 Pa, and polycondensing for 1.5 hours to continuously remove small molecule byproducts. The hydroxyl value of the system was measured to be 110 mgKOH / g, corresponding to a molecular weight of 1000.

[0048] After refining and discharging, the system temperature is lowered to room temperature, and nitrogen is used to break the vacuum. The mixture is then filtered to remove impurities, yielding a light yellow transparent polycarbonate polyol. Example 6

[0049] Under normal pressure, pre-esterification was performed by adding 224.84 g of isosorbide, 180.84 g of coconut oil diol, 180 g of dimethyl carbonate, and 0.061 g of zinc-cobalt bimetallic DMC catalyst to a high-vacuum reaction system. The system was refluxed at 160°C for 2 hours under nitrogen protection, continuously distilling off methanol byproducts. The system was then heated to 180°C to remove excess DMC monomers, yielding hydroxyl-terminated carbonate oligomers. The zinc-cobalt bimetallic DMC catalyst was selected from a bimetallic DMC catalyst obtained by complexing zinc hexacyanocobalaminate with tert-butanol.

[0050] High-temperature, high-vacuum polycondensation was performed by heating the system to 235°C, controlling the vacuum level to be less than 50 Pa, and polycondensing for 2 hours to continuously remove small molecule byproducts. The hydroxyl value of the system was measured to be 55 mgKOH / g, corresponding to a molecular weight of 2000.

[0051] After refining and discharging, the system temperature is lowered to room temperature, and nitrogen is used to break the vacuum. The mixture is then filtered to remove impurities, yielding a light yellow transparent polycarbonate polyol. Example 7

[0052] Using the diol obtained in this invention and one or more isocyanate monomers MDI, TDI, HDI, and IPDI as raw materials, a series of polyurethanes with different uses and properties are prepared by addition polymerization. The performance of the polyurethane waterproof coating obtained in this invention is taken as an example.

[0053] A single-component polyurethane waterproof coating can be prepared by reacting 100 parts of isosorbide-based polyether polyol, 25 parts of diphenylmethane diisocyanate, 0.2 parts of catalyst, 6 parts of latent curing agent, 0.3 parts of defoamer, 50 parts of plasticizer, 12 parts of solvent, 0.3 parts of wetting and dispersing agent, 120 parts of ultrafine talc powder, and 1.2 parts of rheology modifier.

[0054] The specific method is as follows: Isosorbide-based polyether polyol, defoamer, plasticizer, and wetting and dispersing agent are first added to a four-necked flask, stirred and heated to 110℃, then ultrafine talc powder and rheology modifier are added. Vacuum dehydration is then carried out for 5 hours at 120℃ and a gauge pressure of -0.095MPa. Afterwards, the temperature is lowered to 60℃, diphenylmethane diisocyanate is added, and the mixture is stirred for 35 minutes. The temperature is then raised to 85℃ and reacted for 3.5 hours. Finally, the temperature is lowered to 55℃, a catalyst, a latent curing agent, and a solvent are added. After degassing under a vacuum of -0.1MPa for 60 minutes, a one-component polyurethane waterproof coating is obtained. The prepared polyurethane waterproof coating has a tensile strength, elongation at break, and tear strength of 2.53MPa, 845%, and 17.3N / mm, respectively. The retention rates after hot acid and alkali treatment are 94%, 90%, and 95%, respectively; the water absorption rate is 3.2%. It can directly replace existing waterproof coatings for construction.

[0055] The performance testing method for the polyurethane waterproof coating prepared from the isosorbide-based polyether polyol of the present invention refers to GB / T 19250-2013 Polyurethane Waterproof Coating.

[0056] The following table compares the performance of the polyurethane waterproof coating synthesized from the three polyols of this invention with that of ordinary commercially available products:

[0057] It can be seen that the performance of the polyurethane waterproof coatings prepared from the isosorbide-based polyether polyol of this invention is significantly better than that of ordinary commercially available products.

Claims

1. A class of bio-based polyether ester polyols, characterized in that, It is prepared by ring-opening polymerization of propylene oxide with isosorbide and vegetable oil diol as initiators, adding KOH or zinc hexacyanocobaltate as catalysts, and then end-capping with ethylene oxide. The mass ratio of isosorbide to vegetable oil diol in the initiator is 50-80:50-20; the vegetable oil diol is derived from coconut oil, soybean oil, or palm oil. It is a mixture containing copolymers of the following repeating structural units: and Where m is a natural number from 1 to 10, n is a natural number from 1 to 10, and R is the fatty chain of vegetable oil diol, with the fatty chain being a C3-21 hydrocarbon group.

2. A type of bio-based polyester polyol, characterized in that, This product is prepared by esterification and polycondensation reactions using isosorbide, vegetable oil diol, and dimer fatty acids as raw materials, with the addition of tetrabutyl titanate or monobutyltin oxide as catalysts, and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and phosphite as stabilizers. The molar ratio of isosorbide to vegetable oil diol is 60-90:40-10, and the molar ratio of diol to dimer fatty acids in the raw materials is 1.05-1.2:

1. The vegetable oil diol is derived from coconut oil, soybean oil, or palm oil. It is a copolymer containing the following repeating structural units: Where m is a natural number from 1 to 10, n is a natural number from 1 to 10, and R is the fatty chain of vegetable oil diol, with the fatty chain being a C3-21 hydrocarbon group.

3. A class of bio-based polycarbonate polyols, characterized in that, The product is prepared by melt transesterification polycondensation using isosorbide, vegetable oil diol, and dimethyl carbonate as raw materials, with the addition of a sodium iodide-imidazolium sodium complex or a zinc-cobalt bimetallic DMC catalyst. The molar ratio of isosorbide to vegetable oil diol is 60-90:40-10, and the molar ratio of diol to dimethyl carbonate in the raw materials is 1.05-1.2:

1. The vegetable oil diol is derived from coconut oil, soybean oil, or palm oil. The sodium iodide-imidazolium sodium complex is selected from a sodium imidazolium : sodium iodide mass ratio of 2:1 to 6:

1. The zinc-cobalt bimetallic DMC catalyst is selected from a bimetallic DMC catalyst obtained by complexing zinc hexacyanocobaltate with tert-butanol. It is a copolymer containing the following repeating structural units: Where m is a natural number from 1 to 10, n is a natural number from 1 to 10, and R is the fatty chain of vegetable oil diol, with the fatty chain being a C3-21 hydrocarbon group.

4. A type of bio-based polyurethane material, characterized in that, It is prepared by addition polymerization of any one or more polyols according to claims 1-3 with one or more isocyanate monomers MDI, TDI, HDI, and IPDI.

5. A method for preparing a bio-based isosorbide polyol, characterized in that: Using isosorbide and vegetable oil diol as raw materials, three types of bio-based polyols were prepared by adjusting the copolymerization ratio of isosorbide and vegetable oil diol and using different catalytic systems: The polyether ester polyol as described in claim 1, the polyester polyol as described in claim 2, and the polycarbonate polyol as described in claim 3; wherein the vegetable oil diol is derived from coconut oil, soybean oil, or palm oil; The preparation method of the polyether ester polyol is as follows: isosorbide and vegetable oil diol are used as raw materials, KOH or zinc hexacyanocobaltate is added as a catalyst, and ring-opening polymerization is carried out with propylene oxide, followed by end-capping with ethylene oxide; the mass ratio of isosorbide and vegetable oil diol is 50-80:50-20. The preparation method of the polyester polyol is as follows: isosorbide, vegetable oil diol, and dimer fatty acids are used as raw materials, and tetrabutyl titanate or monobutyltin oxide is added as a catalyst, and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] and phosphite are added as stabilizers. The reaction is carried out by gradient temperature esterification and gradient vacuum polycondensation. The molar ratio of isosorbide to vegetable oil diol is 60-90:40-10, and the molar ratio of diol to dimer fatty acids in the raw materials is 1.05-1.2:

1. The preparation method of the polycarbonate polyol is as follows: isosorbide, vegetable oil diol, and dimethyl carbonate are used as raw materials, and a sodium iodide-imidazolium sodium complex or a zinc-cobalt bimetallic DMC catalyst is added for melt transesterification polycondensation; the molar ratio of isosorbide and vegetable oil diol is 60-90:40-10, and the molar ratio of diol to dimethyl carbonate in the raw materials is 1.05-1.2:1; the sodium iodide-imidazolium sodium complex is selected from sodium imidazolium and sodium iodide in a mass ratio of 2:1 to 6:1; the zinc-cobalt bimetallic DMC catalyst is selected from the bimetallic DMC catalyst obtained by complexing zinc hexacyanocobaltate with tert-butanol.

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