Bio-based high-strength polyether ester polyols and their preparation methods
By introducing bio-based high-strength polyether ester polyols with cyclic and benzene ring structures into rigid polyurethane foam, the problems of improving compressive strength and environmental protection have been solved, realizing efficient and environmentally friendly polyurethane foam production.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- SHANDONG INOV NEW MATERIALS CO LTD
- Filing Date
- 2025-12-22
- Publication Date
- 2026-05-26
AI Technical Summary
Existing technologies cannot significantly improve the compressive strength of rigid polyurethane foam through simple and easy methods, and at the same time, they have the problems of dependence on fossil resources and carbon emissions.
By designing the molecular structure of bio-based high-strength polyether ester polyols, introducing a large number of cyclic and benzene ring structures, and employing a simple two-step synthesis process, using bio-based raw materials and DMC catalysts, the ring-opening polymerization and transesterification reactions are completed in a reactor to prepare bio-based high-strength polyether ester polyols.
It significantly improves the compressive strength of rigid polyurethane foam, reduces dependence on fossil resources, reduces carbon emissions, has a simple and easy-to-implement process, is suitable for large-scale production, and has good product performance uniformity.
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Abstract
Description
Technical Field
[0001] This invention belongs to the field of polyether polyol synthesis technology, specifically relating to bio-based high-strength polyether ester polyols and their preparation methods. Background Technology
[0002] Rigid polyurethane foam possesses excellent properties such as good thermal insulation, light weight, high specific strength, and convenient construction. It also exhibits sound insulation, shock absorption, electrical insulation, heat resistance, cold resistance, and solvent resistance. It is widely used in the insulation layers of refrigerators and freezers, cold storage facilities, refrigerated trucks, and as thermal insulation materials for buildings, storage tanks, and pipelines. In the manufacture of seals, shock absorbers, and sound insulation materials, the compressive strength of rigid polyurethane is a crucial parameter for measuring the compressive strength of polyurethane materials, and it is of great significance for its industrial applications. A common method to improve compressive strength is to add fillers. Fillers can increase the density and hardness of polyurethane materials, thereby improving their compressive strength. However, this often leads to problems with polyether precipitation during storage. Another method to improve the compressive strength of polyurethane is to introduce rigid groups into the molecular structure to alter the chemical structure of the polyurethane and increase its strength.
[0003] Patent CN115160556A discloses a bio-based polyether ester polyol and its preparation method. The bio-based polyether ester polyol is polymerized from a mixture of esterified modified soybean oil and propylene oxide under heating conditions. The esterified modified soybean oil is obtained by heating epoxidized soybean oil with a modifying liquid. The modifying liquid comprises the following components by weight: 80-100 parts polyol, 30-40 parts esterified lignin, 16-24 parts polyol polymer, and 8-12 parts ring-opening agent. The esterified lignin is obtained by esterification of lignin with organic acids. This patent mainly relies on esterified lignin and epoxidized soybean oil to introduce ester groups and some rigid structures, but it does not introduce a highly rigid benzene ring structure into the molecular chain, resulting in poor improvement in the compressive strength of rigid polyurethane foam. Its process involves multiple steps such as esterification, ring-opening, and polymerization, making the reaction system complex and difficult to control, easily affecting product consistency and stability.
[0004] Currently, most rigid polyurethane foams are made from petroleum products, which are linked to the extraction of fossil fuels, and the extraction of fossil fuels leads to climate change. With oil resources dwindling, bio-based polyurethane foams, compared to traditional petroleum-based polyurethane, can reduce dependence on petrochemical raw materials while significantly reducing carbon emissions and mitigating the greenhouse effect, offering significant advantages in environmental protection. Summary of the Invention
[0005] To address the shortcomings of existing technologies, the present invention aims to provide a bio-based high-strength polyether ester polyol. Through molecular structure design, the synthesized bio-based polyether ester polyol combines the advantages of both polyether and polyester polyols. Its application in the field of rigid polyurethane foam can reduce the use of petrochemical polyols, which has excellent environmental benefits. At the same time, the introduction of a large number of benzene ring structures into the product structure significantly improves the compressive strength performance of rigid polyurethane foam.
[0006] The present invention also provides a preparation method that is simple, easy to implement, and suitable for large-scale production.
[0007] The bio-based high-strength polyether ester polyol of this invention is prepared from the following raw materials in parts by weight:
[0008] 16-35 parts of small molecule polyols;
[0009] Catalyst 0.005-0.05 parts;
[0010] 10-69 parts of bio-based epoxides;
[0011] 7-56 parts of bio-based phenyl ester compounds;
[0012] The bio-based epoxide is one or more of limonene epoxide, α-pinene oxide, and caryophyllene oxide;
[0013] The bio-based phenyl ester compound is one or both of benzyl benzoate and benzyl cinnamate.
[0014] The small molecule polyol is one or more of 1,3-propanediol, glycerol, sorbitol, and sucrose.
[0015] The catalyst is a bimetallic cyanide complex DMC catalyst.
[0016] The preparation method of the bio-based high-strength polyether ester polyol of the present invention includes the following steps:
[0017] (1) Add small molecule polyols and catalysts to the reactor, stir and heat to dehydrate, and control the temperature and pressure;
[0018] (2) Add bio-based epoxides to carry out polymerization reaction;
[0019] (3) After the reaction is completed, add bio-based phenyl ester compound to the reactor to carry out transesterification reaction. After the reaction is completed, cool down and discharge the material to obtain bio-based high-strength polyether ester polyol product.
[0020] The reaction temperature of the polymerization reaction in step (2) is 100-170℃.
[0021] The transesterification reaction temperature in step (3) is 100-130℃.
[0022] The reaction pressure of the polymerization reaction in step (2) is -0.09-0.5 MPa.
[0023] The reaction pressure of the transesterification reaction in step (3) is -0.09-0.5 MPa.
[0024] The reaction time for the polymerization reaction in step (2) is 5-24 hours.
[0025] The reaction time for the transesterification reaction in step (3) is 0.5-12 h.
[0026] Compared with the prior art, the beneficial effects of the present invention are as follows:
[0027] 1. The small molecule alcohols such as sorbitol and glycerol selected in this invention are bio-based materials. The bio-based epoxides are obtained by epoxidation treatment of natural plant extracts. Bio-based phenyl ester compounds can also be obtained by extraction from natural plants, realizing the full bio-based polyether ester polyol. This reduces the dependence on fossil resources more thoroughly from the source. Compared with traditional petrochemical raw materials, the synthesized full bio-based polyether ester polyol can significantly reduce carbon emissions and has excellent environmental protection significance.
[0028] 2. This invention introduces a large number of cyclic and benzene ring structures into polyol molecules through molecular structure design. The resulting product is applied in the field of rigid polyurethane foam, which increases the content of rigid groups in the molecular chain structure and can significantly improve the strength of rigid polyurethane foam compared with traditional polyether polyols.
[0029] 3. This invention employs a simple two-step method: ring-opening polymerization followed by transesterification. The entire process can be completed sequentially in the same reactor using the same DMC catalyst. The process route is clear, and the reaction conditions are mild and controllable, avoiding complex multi-step reaction systems and cumbersome intermediate product handling. This method significantly reduces the difficulty of process control, increases production efficiency, and is more conducive to large-scale stable production, ensuring the uniformity and reliability of product performance.
[0030] 4. The bio-based high-strength polyether ester polyol obtained in this invention combines the flexibility and hydrolysis resistance of polyether segments with the high strength and high reactivity of polyester segments. It is rich in functional groups, has a tunable molecular structure, and good compatibility with various additives. When used to prepare rigid polyurethane foam, it not only exhibits high compressive strength but also excellent processing performance. Detailed Implementation
[0031] The present invention will be further described below with reference to the embodiments.
[0032] Unless otherwise specified, all raw materials used in the examples were commercially available.
[0033] Example 1
[0034] The method for preparing the bio-based high-strength polyether ester polyol includes the following steps:
[0035] (1) Add 100g of sorbitol to the reactor, accurately weigh 0.2043g of DMC catalyst using an analytical balance and add it to the reactor. Start stirring, and after nitrogen purging, start heating while drawing the reactor to negative pressure. Maintain the temperature at 100℃ and the pressure at -0.09MPa by bubbling nitrogen for 6 hours.
[0036] (2) After dehydration, 30g of limonene epoxide was added to the reactor at -0.09MPa to carry out the polymerization reaction. The reactor was heated to 170℃. After observing the pressure drop in the reactor, the reactor was cooled to 100℃. 250g of limonene epoxide was slowly added to the reactor. After the addition was completed, the temperature was maintained for 24h and the pressure was maintained at 0.5MPa during the reaction.
[0037] (3) After the reaction was completed, 30g of benzyl benzoate was added to the reactor. After nitrogen purging, the transesterification reaction was carried out at 100℃ and 0.1MPa for 0.5h. After the reaction was completed, the temperature was lowered to 90℃ to obtain the bio-based high-strength polyether ester polyol product. The performance indicators are shown in Table 2.
[0038] Example 2
[0039] The method for preparing the bio-based high-strength polyether ester polyol includes the following steps:
[0040] (1) Add 100g of sucrose to the reactor, accurately weigh 0.0149g of DMC catalyst using an analytical balance and add it to the reactor. Start stirring, and after nitrogen replacement, start heating while drawing the reactor to negative pressure. Maintain the temperature at 110℃ and the pressure at -0.09MPa by bubbling with nitrogen for 6 hours.
[0041] (2) After dehydration, 10g of α-pinene oxide was added to the reactor at -0.09MPa to carry out the polymerization reaction. The reactor was heated to 170℃. After observing the pressure drop in the reactor, the temperature was maintained for 5h and the pressure was maintained at 0.4MPa during the reaction.
[0042] (3) After the reaction was completed, 182g of benzyl cinnamate was added to the reactor. After nitrogen purging, the transesterification reaction was carried out at 130℃ and 0.5MPa for 12h. After the reaction was completed, the temperature was lowered to 90℃ to obtain the bio-based high-strength polyether ester polyol product. The performance indicators are shown in Table 2.
[0043] Example 3
[0044] The method for preparing the bio-based high-strength polyether ester polyol includes the following steps:
[0045] (1) Add 100g of glycerol to the reactor, accurately weigh 0.1052g of DMC catalyst using an analytical balance and add it to the reactor. Start stirring, and after nitrogen purging, start heating while drawing the reactor to negative pressure. Maintain the temperature at 120℃ and the pressure at -0.09MPa by bubbling with nitrogen for 6 hours.
[0046] (2) After dehydration, 40g of limonene epoxide was added to the reactor at -0.09MPa to carry out the polymerization reaction. The reactor was heated to 170℃. After observing the pressure drop in the reactor, the reactor was cooled to 130℃. 270g of caryophyllene oxide was slowly added to the reactor. After the addition was completed, the temperature was maintained for 20h and the pressure was maintained at 0.3MPa during the reaction.
[0047] (3) After the reaction was completed, 50g of benzyl benzoate and 150g of benzyl cinnamate were added to the reactor. After nitrogen purging, the transesterification reaction was carried out at 120℃ and 0.2MPa for 8 hours. After the reaction was completed, the temperature was lowered to 90℃ to obtain the bio-based high-strength polyether ester polyol product. The performance indicators are shown in Table 2.
[0048] Comparative Example 1
[0049] The method for preparing the polyether polyol includes the following steps:
[0050] (1) Add 100g of sorbitol to the reactor. Accurately weigh 0.2043g of DMC catalyst using an analytical balance and add it to the reactor. Start stirring. After nitrogen purging, start heating while simultaneously drawing the reactor into a negative pressure. Maintain the temperature at 100℃ and the pressure at -0.09MPa by bubbling with nitrogen for 6 hours.
[0051] (2) After dehydration, 30g of propylene oxide was added to the reactor at -0.09MPa. The reactor was heated to 170℃. After observing a decrease in pressure inside the reactor, the reactor was cooled to 100℃. 280g of propylene oxide was then slowly added to the reactor. After the addition was completed, the temperature was maintained for 24 hours, and the pressure was maintained at 0.5MPa during the reaction. After the reaction was completed, the temperature was lowered to 90℃ to obtain a conventional polyether polyol product. The performance indicators are shown in Table 2.
[0052] Comparative Example 2
[0053] The method for preparing the bio-based polyether ester polyol includes the following steps:
[0054] (1) Add 100g of sucrose to the reactor, accurately weigh 0.0149g of DMC catalyst using an analytical balance and add it to the reactor. Start stirring, and after nitrogen replacement, start heating while drawing the reactor to negative pressure. Maintain the temperature at 110℃ and the pressure at -0.09MPa by bubbling with nitrogen for 6 hours.
[0055] (2) After dehydration, 10g of α-pinene oxide was added to the reactor at -0.09MPa to carry out the polymerization reaction. The reactor was heated to 170℃. After observing the pressure drop in the reactor, the temperature was maintained for 5h and the pressure was maintained at 0.4MPa during the reaction.
[0056] (3) After the reaction was completed, 182g of palm oil was added to the reactor. After nitrogen purging, the transesterification reaction was carried out at 130℃ and 0.5MPa for 12h. After the reaction was completed, the temperature was lowered to 90℃ to obtain the bio-based polyether ester polyol product. The performance indicators are shown in Table 2.
[0057] Comparative Example 3
[0058] The method for preparing the polyether ester polyol includes the following steps:
[0059] (1) Add 100g of sucrose to the reactor, accurately weigh 0.0149g of DMC catalyst using an analytical balance and add it to the reactor. Start stirring, and after nitrogen replacement, start heating while drawing the reactor to negative pressure. Maintain the temperature at 110℃ and the pressure at -0.09MPa by bubbling with nitrogen for 6 hours.
[0060] (2) After dehydration, 10g of propylene oxide was added to the reactor at -0.09MPa to carry out the polymerization reaction. The reactor was heated to 170℃. After observing the pressure drop in the reactor, the temperature was maintained for 5h and the pressure was maintained at 0.4MPa during the reaction.
[0061] (3) After the reaction was completed, 182g of benzyl cinnamate was added to the reactor. After nitrogen purging, the transesterification reaction was carried out at 130℃ and 0.5MPa for 12h. After the reaction was completed, the temperature was lowered to 90℃ to obtain the polyether ester polyol product. The performance indicators are shown in Table 2.
[0062] The test standards and methods used for the product specifications of bio-based high-strength polyether ester polyols are as follows:
[0063] Hydroxyl value: Tested according to GB / T 12008.3-1989 "Determination of hydroxyl value in polyether polyols".
[0064] The following formulation systems were used to foam the products obtained in Examples 1-3 and Comparative Example 1 using the following preparation methods, and their compressive strength was tested. The test results are shown in Table 2.
[0065] The formulation system is shown in Table 1 below:
[0066] Table 1 Formulation System
[0067]
[0068] The TEGOSTAB B8460 is a commercially available product from the German Evonik Industrial Group.
[0069] The preparation method is as follows:
[0070] Accurately weigh the above-mentioned formulation materials into a 500mL beaker to prepare a composite material. Take 50 parts of the above composite material and 50 parts of PM200 and stir thoroughly. Stop stirring when the system is uniform and foam rises, and allow it to foam freely at room temperature. After the foam solidifies, rigid polyurethane foam is obtained. The obtained rigid polyurethane foam sample is tested for compressive strength according to standard GB / T 8813-2008.
[0071] Table 2 Test Results
[0072]
[0073] The test results show that, compared to the conventional polyether polyol in Comparative Example 1 and the partial introduction of raw materials in Comparative Examples 2-3, the compressive strength of Examples 1-3 was significantly improved due to the introduction of a large number of cyclic and benzene ring structures. Furthermore, the raw materials in Examples 1-3 were fully bio-based, with a significantly higher bio-based content than those in Comparative Examples 1-3, which obviously leads to a substantial reduction in carbon emissions and has excellent environmental benefits.
Claims
1. A bio-based high-strength polyether ester polyol, characterized in that, It is prepared from the following parts by weight of raw materials: 16-35 parts of small molecule polyols; Catalyst 0.005-0.05 parts; 10-69 parts of bio-based epoxides; 7-56 parts of bio-based phenyl ester compounds; The bio-based epoxide is one or more of limonene epoxide, α-pinene oxide, and caryophyllene oxide; The bio-based phenyl ester compound is one or both of benzyl benzoate and benzyl cinnamate; The catalyst is a bimetallic cyanide complex DMC catalyst; The method for preparing the bio-based high-strength polyether ester polyol includes the following steps: (1) Add small molecule polyols and catalysts to the reaction vessel, stir and heat to dehydrate; (2) Add bio-based epoxides to carry out polymerization reaction; (3) After the reaction is completed, add bio-based phenyl ester compound to the reactor to carry out transesterification reaction. After the reaction is completed, cool down and discharge the material to obtain bio-based high-strength polyether ester polyol product.
2. The bio-based high-strength polyether ester polyol according to claim 1, characterized in that, The small molecule polyol is one or more of 1,3-propanediol, glycerol, sorbitol, and sucrose.
3. A method for preparing a bio-based high-strength polyether ester polyol according to any one of claims 1-2, characterized in that, Includes the following steps: (1) Add small molecule polyols and catalysts to the reaction vessel, stir and heat to dehydrate; (2) Add bio-based epoxides to carry out polymerization reaction; (3) After the reaction is completed, add bio-based phenyl ester compound to the reactor to carry out transesterification reaction. After the reaction is completed, cool down and discharge the material to obtain bio-based high-strength polyether ester polyol product.
4. The method for preparing bio-based high-strength polyether ester polyol according to claim 3, characterized in that, The reaction temperature of the polymerization reaction in step (2) is 100-170℃.
5. The method for preparing bio-based high-strength polyether ester polyol according to claim 3, characterized in that, The transesterification reaction temperature in step (3) is 100-130℃.
6. The method for preparing bio-based high-strength polyether ester polyol according to claim 3, characterized in that, The reaction pressure of the polymerization reaction in step (2) is -0.09-0.5 MPa.
7. The method for preparing bio-based high-strength polyether ester polyol according to claim 3, characterized in that, The reaction pressure of the transesterification reaction in step (3) is -0.09-0.5 MPa.
8. The method for preparing bio-based high-strength polyether ester polyol according to claim 3, characterized in that, The reaction time for the polymerization reaction in step (2) is 5-24 hours.
9. The method for preparing bio-based high-strength polyether ester polyol according to claim 3, characterized in that, The reaction time for the transesterification reaction in step (3) is 0.5-12 h.