High-functionality plant-phenol-based polyether polyol, method for preparing the same, and polyurethane adhesive

Abstract

The application relates to the technical field of polyols, and particularly discloses a high-functionality plant phenol-based polyether polyol, a preparation method thereof and a polyurethane adhesive. The high-functionality plant phenol-based polyether polyol is prepared from plant phenol glycidyl ether and a dihydroxyl compound with a molar ratio of 1:(1.8-2.2). The preparation method comprises the following steps: obtaining a polyol intermediate by reacting the plant phenol glycidyl ether and the dihydroxyl compound under the action of a first catalyst, and then obtaining the product by reacting the polyol intermediate under the action of a second catalyst. The high-functionality plant phenol-based polyether polyol has multiple high-reactivity hydroxyl groups, significantly improves the hydroxyl content and the reactivity of a plant phenol-based high-molecular material, and widens the application range.

Description

Technical Field

[0001] This application relates to the field of polyol technology, and more specifically, to a high-functionality plant phenolic polyether polyol, its preparation method, and a polyurethane adhesive. Background Technology

[0002] Cashew nut shell oil is extracted from the soft, honeycomb-like structure of cashew nut shells, while cardiac glycosides are compounds containing two hydroxyl functional groups obtained through the refining and purification of cashew nut shell oil. They are natural, green, and environmentally friendly renewable resources. Cardiac glycosides are primarily composed of a benzene ring with three reaction sites: the phenolic hydroxyl group, the 0-3 unsaturated bonds on the meta-C15 long side chain of the phenolic hydroxyl group, and the active hydrogen atom on the benzene ring. This unique chemical structure gives cardiac glycosides both the rigidity of a benzene ring and the flexibility of a long carbon chain; it exhibits characteristics of both aromatic compounds and aliphatic hydrocarbons.

[0003] The preparation of cardiac phenol-based polyether polyols from cardiac phenols and polyols increases the number of functional groups in plant phenol molecules, effectively improving the bioavailability of plant phenols and providing more possibilities for further chemical modification and functionalization. This gives plant phenol-based polyether polyols greater potential for developing novel bio-based materials and broad application prospects in the fields of surfactants, crosslinking modifiers, and other polymer materials technologies.

[0004] Regarding the aforementioned technologies, the inventors discovered that currently, polyether polyol materials containing plant phenols are mainly monohydroxyl polyoxyethylene ethers and polyoxypropylene ethers. These substances are prepared by adding ethylene oxide or propylene oxide to the active groups of plant phenols. These types of polyether polyols have a limited number of hydroxyl groups, generally existing only as end caps or branches in the polymer structure, severely limiting the application of plant phenol-based polyether polyols. Summary of the Invention

[0005] In order to increase the active hydroxyl content of plant phenolic polyether polyols, this application provides a high-functionality plant phenolic polyether polyol and its preparation method.

[0006] In a first aspect, this application provides a high-functionality plant-based phenolic polyether polyol, employing the following technical solution: a high-functionality plant-based phenolic polyether polyol, the raw materials comprising plant-based phenolic glycidyl ether and a dihydroxy compound in a molar ratio of 1:(1.8-2.2); the structural formula of the plant-based phenolic glycidyl ether is as follows: Where n is 0, 2, 4, or 6; the structure of the high-functionality plant-based phenolic polyether polyol is as follows: Wherein R is a characteristic segment of the dihydroxy compound.

[0007] By adopting the above technical solution, plant phenolic polyether polyols can be prepared from plant phenolic glycidyl ethers and dihydroxy compounds with specific structural formulas within a specified molar ratio range. This allows for effective control of the functionality and molecular weight distribution of the product, resulting in a product with high functionality.

[0008] The product retains the long alkyl side chains and double bonds of plant phenols, while introducing rigid benzene rings and flexible polyether long chains, significantly improving the bonding strength, mechanical properties, and aging resistance of plant phenol-based polyether polyols in application. Simultaneously, the resulting product possesses four or more highly reactive hydroxyl groups, significantly increasing the hydroxyl content and reactivity of the polyether polymer material, providing more possibilities for further chemical modification and functionalization.

[0009] Optionally, the dihydroxy compound is a straight-chain or branched dihydroxy structure, selected from any one or more combinations of bisphenol A, bisphenol S, polypropylene glycol, or polyethylene glycol.

[0010] By adopting the above technical solution, the use of straight-chain or branched dihydroxyl structures can make the hydroxyl groups of the obtained plant phenolic polyether polyols relatively open, with less steric hindrance, more exposed hydroxyl groups, and correspondingly improved hydroxyl reactivity, making the plant phenolic polyether polyols more likely to react with other functional groups.

[0011] Furthermore, the introduction of straight-chain or branched molecular structures gives the product's molecular chain greater flexibility. This flexibility helps the molecular chain better adjust its conformation during the reaction, making it easier for hydroxyl groups to approach and react with other functional groups.

[0012] Optionally, the dihydroxy compound is selected from any one or a combination of two of polypropylene glycol or polyethylene glycol.

[0013] By adopting the above technical solution, polypropylene glycol and polyethylene glycol are linear or slightly branched polymers, whose molecular structures contain multiple repeating ether bonds and terminal hydroxyl groups, which can significantly improve the functionality of the product.

[0014] In contrast, the molecular structures of bisphenol A and bisphenol S are relatively complex, and the hydroxyl groups may be hindered by adjacent benzene rings or groups, leading to reduced reactivity. The availability of hydroxyl groups is also lower than that of polypropylene / ethylene glycol, making their reaction with plant phenolic glycidyl ethers relatively difficult. However, in the structures of polypropylene glycol and polyethylene glycol, the hydroxyl groups can more easily attack the epoxy groups of glycidyl ethers, opening the epoxy ring and forming stable intermediates, thus facilitating subsequent reactions. Furthermore, the plant phenolic polyether polyols generated from polypropylene glycol and polyethylene glycol exhibit higher reactivity and provide greater performance enhancement to polyurethanes.

[0015] Secondly, this application provides a method for preparing high-functionality plant-based phenolic polyether polyols, using the following technical solution:

[0016] A method for preparing a high-functionality plant-based phenolic polyether polyol includes the following steps:

[0017] The dihydroxy compound and the first catalyst were mixed according to the formula, and the temperature was raised to 85-100℃. Then, the plant phenol glycidyl ether was slowly added, and the temperature was kept at 85-100℃ for 2-6 hours to obtain the polyol intermediate.

[0018] A second catalyst is added to the polyol intermediate, and the mixture is heated to 80-90°C under a nitrogen atmosphere. Then ethylene oxide is added, and the polymerization reaction is carried out at 130-150°C. Finally, the mixture is cooled to room temperature to obtain the final product.

[0019] By setting up the above process and controlling the ratio of dihydroxy compounds and phytophenol glycidyl ethers, the functionality and molecular weight distribution of the product can be effectively controlled, resulting in a product with high functionality. Phytophenols are derived from natural plants, are renewable, and have good biodegradability, meaning that they can be decomposed by microorganisms in the natural environment after use, without causing long-term pollution to the environment.

[0020] Compared to traditional petroleum-based polyols as raw materials, this application meets the requirements of environmental protection and sustainable development, and helps reduce carbon emissions and environmental pollution. Furthermore, the preparation method of this application is relatively mild and suitable for large-scale industrial production.

[0021] Optionally, the first catalyst is added at 0.1-1% of the total mass of the dihydroxy compound and phytophenol glycidyl ether; the second catalyst is added at 0.1-1% of the mass of the intermediate; and the ethylene oxide is added at 1-10% of the mass of the intermediate.

[0022] Optionally, the first catalyst is selected from any one or more of benzyltrimethylammonium bromide, benzyltriethylammonium bromide, benzyltributylammonium bromide, tetramethylammonium bromide, tetraethylammonium bromide, tetrapropylammonium bromide, tetrabutylammonium bromide, hexadecyltrimethylammonium bromide, boron trifluoride ether, triphenylphosphine, sodium hydroxide, or potassium hydroxide.

[0023] Optionally, the second catalyst is selected from any one or more of alkali metal catalysts, bimetallic cyanide catalysts, and alkyl aluminum phosphate catalysts.

[0024] By adopting the above technical solution and using the first / second catalyst of this application, and preparing the product according to the corresponding amount of additives, the ring-opening polymerization reaction and the polymerization reaction of ethylene oxide can be effectively promoted, which helps to control the functionality and molecular weight distribution of the product.

[0025] Optionally, one of the high-functionality plant-based phenolic polyether polyols of this application can be used in the preparation of surfactants, adhesives, environmentally friendly coatings, crosslinking modifiers, packaging materials, and the synthesis of polyurethane.

[0026] Thirdly, this application provides a polyurethane adhesive prepared using the high-functionality plant-based phenolic polyether polyol of this application.

[0027] Optionally, the high-functionality plant-based phenolic polyether polyol in the polyurethane adhesive accounts for 1-3.5% by mass.

[0028] By adopting the above technical solution, the high-functionality plant phenolic polyether polyol of this application has a large number of hydroxyl groups in different branches, which is more conducive to polycondensation and cross-linking, forming more adhesive sites. When the high-functionality plant phenolic polyether polyol of this application is added to the polyurethane adhesive at 1-3.5%, the viscosity of the system increases significantly, indicating that the hydroxyl groups in the high-functionality plant phenolic polyether polyol have high activity and can cross-link rapidly in the system. In two-component polyurethane adhesives, this can significantly improve the adhesive strength and increase the toughness.

[0029] In summary, this application has the following beneficial effects:

[0030] 1. Since this application uses plant phenol glycidyl ether with a specific structure and a dihydroxy compound as raw materials to prepare plant phenol-based polyether polyols, the product retains the long alkyl side chains and double bonds in plant phenols, introduces rigid benzene rings and flexible polyether long chains, and has 4 or more highly reactive hydroxyl groups, which significantly improves the functionality of the product and provides more possibilities for further chemical modification and functionalization, effectively broadening the application range of plant phenol-based polyether polymer materials.

[0031] 2. In this application, a straight-chain or branched dihydroxyl structure is preferred, which makes the hydroxyl groups of the obtained plant phenolic polyether polyol relatively open, with less steric hindrance, and the hydroxyl groups are more exposed, thereby further improving the hydroxyl reactivity of the product plant phenolic polyether polyol.

[0032] 3. The preparation method of this application is relatively mild and can effectively promote the ring-opening polymerization reaction and the polymerization reaction of ethylene oxide, which helps to control the functionality and molecular weight distribution of the product and is suitable for large-scale industrial production.

[0033] 4. The high-functional-group plant phenolic polyether polyol of this application, when applied to the preparation of polyurethane adhesives, can rapidly crosslink in the system, significantly increase the viscosity rise rate of the system, improve the adhesive strength, and increase the toughness of the adhesive. Attached Figure Description

[0034] Figure 1 The deuterated chloroform phase after derivatization of the product obtained in Example 6 1 H-NMR spectrum.

[0035] Figure 2 The viscosity increase rate of the polyurethane adhesive system obtained in Application Example 1 and Comparative Example 1 was tested. Detailed Implementation

[0036] The following embodiments provide a further detailed description of this application.

[0037] raw material

[0038] Unless otherwise specified, all raw materials used in the embodiments and comparative examples in this application are commercially available products, specifically:

[0039] Bisphenol A, selected from Shanghai Yuanye Biotechnology Co., Ltd., T90137;

[0040] Bisphenol S, selected from Shanghai Yuanye Biotechnology Co., Ltd., B27890;

[0041] Polypropylene glycol, HO(C3H6O)nH, has an average molecular weight of 2000.

[0042] Polyethylene glycol, HO(CH2CH2O)nH, has an average molecular weight of 2000;

[0043] Boron trifluoride diethyl ether, selected from Hans Chemical, B802217;

[0044] Sodium hydride, selected from Jinan Huifengda Chemical Co., Ltd., HFD-698;

[0045] Ethylene oxide, selected from JESK, KA776847;

[0046] Toluene diisocyanate, selected from Shanghai Yuanye Biotechnology Co., Ltd., W10121;

[0047] Polyhexyl adipate, selected from Jiangsu Congzhong Chemical Co., Ltd., 13832;

[0048] Dibutyltin dilaurate, selected from Shanghai Yuanye Biotechnology Co., Ltd., W10608.

[0049] Example

[0050] Example 1

[0051] A high-functionality plant-based phenolic polyether polyol, comprising plant-based phenolic glycidyl ether and a dihydroxy compound in a molar ratio of 1:2, wherein the structural formula of the plant-based phenolic glycidyl ether is as follows: The dihydroxy compound is bisphenol A; the first catalyst is boron trifluoride diethyl ether; the second catalyst is sodium hydride, an alkali metal catalyst.

[0052] The preparation method of the above-mentioned high-functionality plant phenolic polyether polyol includes the following steps:

[0053] S1: The dihydroxy compound and the first catalyst are mixed in a certain proportion to obtain a blend;

[0054] S2: Add the blend to a four-necked flask, stir and mix evenly, purge with nitrogen to replace the air, heat to 85°C under nitrogen protection, and slowly add 43.5g of plant phenol glycidyl ether. The amount of the first catalyst added is 0.3% of the total mass of the dihydroxy compound and plant phenol glycidyl ether. Keep warm at 90°C for 4 hours to obtain the polyol intermediate.

[0055] S3: The above polyol intermediate was added to a high-pressure reactor, followed by a second catalyst, the amount of which was 0.8% of the mass of the intermediate. Nitrogen gas was introduced to replace the air. Under the protective atmosphere of nitrogen, the temperature was raised to 90°C, and then ethylene oxide was added, the amount of which was 4% of the mass of the intermediate. The polymerization reaction was carried out at 150°C. After the reaction was completed, the mixture was cooled to room temperature to obtain a high-functionality plant phenolic polyether polyol, the structure of which is as follows:

[0056] Where n is 0, and R is the characteristic chain segment of bisphenol A.

[0057] Example 2

[0058] A high-functionality plant-based phenolic polyether polyol differs from Example 1 in that the raw materials include plant-based phenolic glycidyl ether and a dihydroxy compound in a molar ratio of 1:1.8, wherein the structural formula of the plant-based phenolic glycidyl ether is as follows:

[0059] The preparation method of the above-mentioned high-functionality plant phenolic polyether polyol includes the following steps:

[0060] S1: The dihydroxy compound and the first catalyst are mixed in a certain proportion to obtain a blend;

[0061] S2: Add the blend to a four-necked flask, stir and mix evenly, purge with nitrogen to replace the air, heat to 85°C under nitrogen protection, and slowly add 43.5g of plant phenol glycidyl ether. The amount of the first catalyst added is 1% of the total mass of the dihydroxy compound and plant phenol glycidyl ether. Keep warm at 85°C for 6 hours to obtain the polyol intermediate.

[0062] S3: The polyol intermediate is added to a high-pressure reactor, followed by a second catalyst, the amount of which is 1% of the mass of the intermediate. Nitrogen gas is introduced to replace the air. Under the protective atmosphere of nitrogen, the temperature is raised to 80°C, and then ethylene oxide is added, the amount of which is 10% of the mass of the intermediate. The polymerization reaction is carried out at 130°C. After the reaction is completed, the mixture is cooled to room temperature to obtain a high-functionality plant phenolic polyether polyol, the structure of which is as follows:

[0063] Where n is 2 and R is the characteristic chain segment of bisphenol A.

[0064] Example 3

[0065] A high-functionality plant-based phenolic polyether polyol differs from Example 1 in that the raw materials include plant-based phenolic glycidyl ether and a dihydroxy compound in a molar ratio of 1:2.1, wherein the structural formula of the plant-based phenolic glycidyl ether is as follows:

[0066] The preparation method of the above-mentioned high-functionality plant phenolic polyether polyol includes the following steps:

[0067] S1: The dihydroxy compound and the first catalyst are mixed in a certain proportion to obtain a blend;

[0068] S2: Add the blend to a four-necked flask, stir and mix evenly, purge with nitrogen to replace the air, heat to 90°C under nitrogen protection, and slowly add 43.5g of plant phenol glycidyl ether. The amount of the first catalyst added is 0.5% of the total mass of the dihydroxy compound and plant phenol glycidyl ether. Keep warm at 100°C for 2 hours to obtain the polyol intermediate.

[0069] S3: The polyol intermediate is added to a high-pressure reactor, followed by a second catalyst at a mass of 0.1% of the intermediate. Nitrogen gas is introduced to replace the air. Under a nitrogen protective atmosphere, the temperature is raised to 90°C, and ethylene oxide at a mass of 1% of the intermediate is added. The polymerization reaction is carried out at 140°C. After the reaction is completed, the mixture is cooled to room temperature to obtain a high-functionality plant-based phenolic polyether polyol, the structure of which is as follows:

[0070] Where n is 4 and R is the characteristic chain segment of bisphenol A.

[0071] Example 4

[0072] A high-functionality plant-based phenolic polyether polyol differs from Example 1 in that the raw materials include plant-based phenolic glycidyl ether and a dihydroxy compound in a molar ratio of 1:2.2, wherein the structural formula of the plant-based phenolic glycidyl ether is as follows: The dihydroxy compound is bisphenol A; the first catalyst is boron trifluoride diethyl ether;

[0073] The preparation method of the above-mentioned high-functionality plant phenolic polyether polyol includes the following steps:

[0074] S1: The dihydroxy compound and the first catalyst are mixed in a certain proportion to obtain a blend;

[0075] S2: Add the blend to a four-necked flask, stir and mix evenly, purge with nitrogen to replace the air, heat to 100°C under nitrogen protection, and slowly add 43.5g of plant phenol glycidyl ether. The amount of the first catalyst added is 0.1% of the total mass of the dihydroxy compound and plant phenol glycidyl ether. Keep warm at 100°C for 4 hours to obtain the polyol intermediate.

[0076] S3: The polyol intermediate is added to a high-pressure reactor, followed by a second catalyst at a mass of 0.4% of the intermediate. Nitrogen gas is introduced to replace the air. Under a nitrogen protective atmosphere, the temperature is raised to 80°C, and ethylene oxide at a mass of 3% of the intermediate is added. The polymerization reaction is carried out at 150°C. After the reaction is completed, the mixture is cooled to room temperature to obtain a high-functionality plant-based phenolic polyether polyol, the structure of which is as follows:

[0077] Where n is 6 and R is the characteristic chain segment of bisphenol A.

[0078] Example 5

[0079] A high-functionality plant-based phenolic polyether polyol differs from Example 1 in that the dihydroxy compound in the raw material is bisphenol S, while all other steps are the same as in Example 1. The structure of the product, the high-functionality plant-based phenolic polyether polyol, is as follows: Where n is 0, and R is the characteristic chain segment of bisphenol S.

[0080] Example 6

[0081] A high-functionality plant-based phenolic polyether polyol differs from Example 1 in that the dihydroxy compound in the raw material is polypropylene glycol; all other steps are the same as in Example 1. The structure of the product, the high-functionality plant-based phenolic polyether polyol, is as follows: Where n is 0 and R is a characteristic segment of polypropylene glycol.

[0082] Example 7

[0083] A high-functionality plant-based phenolic polyether polyol differs from Example 1 in that the dihydroxy compound in the raw material is polyethylene glycol; all other steps are the same as in Example 1. The structure of the product, the high-functionality plant-based phenolic polyether polyol, is as follows: Where n is 0 and R is a characteristic segment of polyethylene glycol.

[0084] Example 8

[0085] A high-functionality plant-based phenolic polyether polyol differs from Example 1 in that the dihydroxy compound in the raw materials is a mixture of polyethylene glycol and polypropylene glycol in a molar ratio of 1:2. All other steps are the same as in Example 1. The structure of the resulting high-functionality plant-based phenolic polyether polyol is as follows:

[0086] Where n is 0, and R is a combination of polypropylene glycol and polyethylene glycol characteristic segments.

[0087] Application examples

[0088] Application Example 1

[0089] A polyurethane adhesive, the raw materials and their amounts are shown in Table 1, wherein the high-functionality plant phenolic polyether polyol is the high-functionality plant phenolic polyether polyol obtained in Example 1; and the polyisocyanate is toluene diisocyanate.

[0090] Table 1

[0091]

[0092] The preparation method of the above-mentioned polyurethane adhesive includes the following steps:

[0093] S1: Mix and stir high-functionality plant phenolic polyether polyol, polyhexamethylene adipate, polyisocyanate and calcium carbonate, heat to 80℃ and react for 2.5 h under nitrogen protection, and then degas under vacuum for 0.5 h to obtain component A.

[0094] S2: Pour the high-functionality plant phenolic polyether polyol into a beaker, add 1,4-butanediol, dibutyltin dilaurate and calcium carbonate, heat to 80℃ and stir for 1.5h under a nitrogen atmosphere to obtain component B;

[0095] S3: Mix component B and component A, stir evenly, pour into a mold, vacuum at 80℃ until the air bubbles disappear or are minimal, and cure at a constant temperature to obtain the final product.

[0096] Application Example 2-4

[0097] A polyurethane adhesive differs from Application Example 1 in that the raw materials and amounts are shown in Table 1, while the other steps are the same as in Application Example 1.

[0098] Application Example 5-11

[0099] A polyurethane adhesive differs from Application Example 1 in that the source of the high-functionality plant-based phenolic polyether polyol in the raw materials is shown in Table 2, while the other steps are the same as in Application Example 1.

[0100] Table 2

[0101]

[0102] Comparative Example

[0103] Comparative Example 1

[0104] A polyurethane adhesive differs from Application Example 1 in that the high-functionality plant phenolic polyether polyol in the raw materials is replaced with an equal mass of polyhexanediol adipate, while all other steps are the same as in Application Example 1.

[0105] Performance testing

[0106] Test Example 1: High-functionality plant-based phenolic polyether polyols

[0107] The appearance, viscosity and hydroxyl content of the high-functionality plant phenolic polyether polyols obtained in Examples 1-8 were tested. Each group of tests was conducted 3 times, and the average value was taken as the final result. The final results are recorded in Table 3.

[0108] 1. Viscosity: The viscosity was tested in accordance with the relevant provisions of GB / T 12008.7—2010 "Plastics Polyether Polyols Part 7: Determination of Viscosity".

[0109] 2. Volatility: The content of non-volatile substances shall be tested in accordance with the relevant provisions of GB / T 2793 "Determination of Non-volatile Content in Adhesives".

[0110] 3. Hydroxyl content: Referring to the relevant provisions of GB / T 12008.3-2009 "Plastic Polyether Polyols Part 3: Determination of Hydroxyl Value", the hydroxyl content was tested by the phthalic anhydride method.

[0111] Table 3

[0112]

[0113]

[0114] As can be seen from the performance test results in Table 3, the high-functionality plant phenolic polyether polyol of this application is a yellow transparent liquid with uniform color and physical state.

[0115] The high-functionality plant-based phenolic polyether polyol of this application has a viscosity range of 1000-2500 mPa·s / 25℃, a non-volatile content of ≥99.7%, and a hydroxyl value range of 50-220 mgKOH / g. This indicates that the high-functionality plant-based phenolic polyether polyol of this application has a large number of highly reactive hydroxyl groups, high purity, and can impart better reactivity and higher crosslinking density to the product, resulting in a higher viscosity value.

[0116] When polyethylene glycol and polypropylene glycol are used as dihydroxy compounds to prepare plant phenolic polyether polyols, the hydroxyl groups in the products are more easily exposed, giving the plant phenolic polyether polyols higher hydroxyl reactivity, which significantly increases their viscosity.

[0117] Test Example 2: Structure Test of High-Functionality Plant-Based Phenolic Polyether Polyols

[0118] The structure of the product obtained in Example 6 was tested by proton nuclear magnetic resonance spectroscopy.

[0119] Figure 1 The deuterated chloroform phase after derivatization of the obtained product 1 The 1H-NMR spectrum shows the chemical shift of the methylene group attached to the primary hydroxyl group at 4.29 ppm.

[0120] From hydroxyl value and 1 The H-NMR spectrum shows that the main components are high-functionality plant-based phenolic polyether polyols with the following structures: R represents the characteristic segment of polypropylene glycol, which is consistent with the theoretical structure.

[0121] Test Example 3: Mechanical Property Testing of Polyurethane Adhesives

[0122] The following performance tests were conducted on a polyurethane adhesive obtained in corresponding use cases 1-11 and comparative example 1. Each test was conducted 3 times, and the average value was taken as the final result. The final results are recorded in Table 4.

[0123] 1. Shear strength test: The test was conducted in accordance with GB / T 7124-2008 standard. After mixing components A and B evenly, 3003 aluminum material without primer and surface treatment was bonded together to prepare shear test specimens. The shear test specimens were cured for 7 days at a temperature of (23±2)℃ and a relative humidity of (50±5)%RH, with an adhesive layer thickness of 0.5mm, and the shear strength was tested.

[0124] 2. Tensile strength and elongation at break test: After the components A and B are mixed evenly, they are pressed into a sheet with a thickness of about 2 mm and cured for 7 days at a temperature of (23±2)℃ and a relative humidity of (50±5)%RH. The test is performed according to the standard, using a type 1 tool, and according to GB / T 528.

[0125] 3. Peel strength: After mixing components A and B evenly to form a polyurethane adhesive, the peel strength of the adhesive is tested using a universal testing machine in accordance with the adhesive peel strength test method (flexible material to flexible material) in GB-T 2791-1995 standard.

[0126] Table 4

[0127]

[0128] As can be seen from the performance test results in Table 4, the high-functionality plant-based phenolic polyether polyol of this application can be used to prepare two-component polyurethane adhesives. Using the high-functionality plant-based phenolic polyether polyol of this application as a raw material to prepare polyurethane adhesives can significantly improve the mechanical properties of the polyurethane adhesives.

[0129] When polypropylene glycol and polyethylene glycol are used as dihydroxy compounds, they exhibit better mechanical properties than bisphenol A and bisphenol S when used to prepare high-functionality plant-based phenolic polyether polyols in the preparation of polyurethane adhesives. The selection of polypropylene glycol and polyethylene glycol as dihydroxy compounds imparts better mechanical properties and peel strength to polyurethane adhesives. This may be due to two factors: firstly, the mixed dihydroxy compounds exhibit better reactivity in the ring-opening reaction; secondly, the side chains of polypropylene glycol can maintain a stable network structure to a certain extent in the polyurethane adhesive system, obtaining more stable crosslinking sites, while the linear structure of polyethylene glycol is beneficial for improving toughness and supplementing adhesive sites. Optimal mechanical properties are achieved by controlling the mixing of polyethylene glycol and polypropylene glycol at a molar ratio of 1:2.

[0130] Test Example 4: Testing the Tackifying Properties of Polyurethane Adhesives

[0131] The rate of increase in system viscosity of the polyurethane adhesive obtained corresponding to Case 1 and Comparative Example 1 was detected, and the viscosity values ​​of the system were measured at different times and plotted.

[0132] like Figure 2 As shown, 1% of the high-functionality plant-based phenolic polyether polyol of this application, when used in the preparation of polyurethane adhesives, can rapidly increase the viscosity of the system. This also indicates that the hydroxyl groups in the high-functionality plant-based phenolic polyether polyol of this application have higher activity, enabling rapid cross-linking and quickly improving adhesion and toughness in two-component polyurethane adhesives.

[0133] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A high-functionality plant phenol-based polyether polyol, characterized in that, The raw materials include a plant phenol glycidyl ether and a dihydroxyl compound in a molar ratio of 1:(1.8-2.2); the structural formula of the plant phenol glycidyl ether is wherein n is 0, 2, 4 or 6; the high-functionality plant phenol-based polyether polyol has the following structure: wherein R is a characteristic segment of the dihydroxyl compound selected from any one or combination of bisphenol A, bisphenol S, polypropylene glycol, or polyethylene glycol.

2. The high-functionality plant-phenol-based polyether polyol according to claim 1, characterized by, The dihydroxy compound is selected from any one or a combination of both of polypropylene glycol or polyethylene glycol.

3. A process for the preparation of a high functionality plant phenol based polyether polyol according to any one of claims 1-2, characterized in that, The method comprises the following steps: The dihydroxy compound and the first catalyst are blended in a certain proportion, and the plant phenol glycidyl ether is slowly added after being warmed to 85-100℃, and then the mixture is incubated at 85-100℃ for 2-6h to obtain a polyol intermediate, wherein the first catalyst is boron trifluoride etherate; The second catalyst, which is an alkali metal catalyst, is added to the polyol intermediate, and the mixture is warmed to 80-90℃ under a nitrogen atmosphere, and then the polyethylene oxide is added and the mixture is subjected to a polymerization reaction at 130-150℃, and then the mixture is cooled to room temperature.

4. The process for the preparation of high functionality plant phenol based polyether polyol as claimed in claim 3, wherein, The addition amount of the first catalyst is 0.1-1% of the total mass of the dihydroxy compound and the plant phenol glycidyl ether; the addition amount of the second catalyst is 0.1-1% of the mass of the intermediate; and the addition amount of the polyethylene oxide is 1-10% of the mass of the intermediate.

5. A polyurethane adhesive, characterized by The polyurethane adhesive is prepared by using the high-functionality plant phenol-based polyether polyol according to any one of claims 1-2.

6. The polyurethane adhesive according to claim 5, wherein The mass proportion of the high-functionality plant phenol-based polyether polyol in the polyurethane adhesive is 1-3.5%.

Images