Pentafluorophenol modified anthranilic acid polyether polyol, preparation method thereof and application of pentafluorophenol modified anthranilic acid polyether polyol in rigid polyurethane foam

Abstract

The invention belongs to the technical field of polyether polyol and preparation thereof, and particularly relates to pentafluorophenol modified o-aminobenzoic acid polyether polyol, a preparation method thereof and application of the pentafluorophenol modified o-aminobenzoic acid polyether polyol in rigid polyurethane foam. The pentafluorophenol modified o-aminobenzoic acid polyether polyol is prepared by taking pentafluorophenol modified o-aminobenzoic acid and polyol as a mixed initiator and polymerizing the mixed initiator with alkylene oxide under the action of a composite catalyst, the pentafluorophenol modified anthranilic acid is prepared by carrying out esterification reaction on pentafluorophenol and anthranilic acid in a molar ratio of 1: (1-1.2). The pentafluorophenol modified o-aminobenzoic acid polyether polyol provided by the invention is moderate in viscosity, hydroxyl value and functionality, and when the pentafluorophenol modified o-aminobenzoic acid polyether polyol is applied to preparation of rigid polyurethane foam, the heat conductivity coefficient of the rigid polyurethane foam can be effectively reduced, and the thermal insulation performance of the rigid polyurethane foam is improved. The invention also provides a preparation method of the pentafluorophenol modified anthranilic acid polyether polyol.

Description

Technical Field

[0001] The invention belongs to the technical field of polyether polyols and preparation thereof, and specifically relates to pentafluorophenol-modified o-aminobenzoic acid polyether polyol and a preparation method thereof and application thereof in rigid polyurethane foam. Background Art

[0002] Polyether polyols, as a class of materials with excellent physical and chemical properties, have demonstrated wide application value in many industrial fields such as foam plastics, elastomers, coatings and adhesives. These traditional polyether polyol products meet many industrial needs with their unique performance advantages. However, with the rapid development of industrial technology and the continuous improvement of safety and environmental protection standards, the market's performance requirements for polyether polyols are becoming increasingly stringent.

[0003] In the foam plastics industry, due to safety considerations, the flame retardancy of polyether polyols has become an important consideration, requiring the material to exhibit a lower fire spread rate and higher self-extinguishing ability when burning. In the field of coatings and adhesives, the weather resistance and chemical resistance of polyether polyols have become key factors in determining their service life and application range, requiring the material to be able to withstand harsh environmental conditions and chemical erosion.

[0004] In order to meet these challenges, the development of new modified polyether polyols to improve their performance in specific application areas has become a hot topic in the current research field of polyether polyols. Among them, pentafluorophenol, as a compound with significant flame retardant effect, is widely recognized for its potential to be introduced into the molecular structure of polyether polyols, and is expected to significantly improve the flame retardant properties of the material. At the same time, as a functional compound, the unique chemical structure of anthranilic acid can bring enhanced compressive strength and chemical resistance to polyether polyols, especially in downstream foaming applications.

[0005] However, effectively introducing pentafluorophenol and o-aminobenzoic acid into the molecular structure of polyether polyols and ensuring the stability of the modified polyether polyols is a major challenge facing current technologies. This requires not only a high degree of accuracy and controllability in the synthesis process, but also the need to ensure that no impurities or by-products that affect the material properties are introduced during the modification process. Summary of the invention

[0006] The technical problem to be solved by the present invention is to overcome the above-mentioned defects of the prior art and provide a pentafluorophenol-modified anthranilic acid polyether polyol, which has moderate viscosity, hydroxyl value and functionality. When the pentafluorophenol-modified anthranilic acid polyether polyol is used to prepare a rigid polyurethane foam, the thermal conductivity of the rigid polyurethane foam can be effectively reduced and its thermal insulation performance can be improved. The present invention also provides a preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol.

[0007] The pentafluorophenol-modified anthranilic acid polyether polyol of the present invention is obtained by polymerizing pentafluorophenol-modified anthranilic acid and polyol as mixed initiators with alkylene oxide under the action of a composite catalyst; wherein the pentafluorophenol-modified anthranilic acid is obtained by esterification reaction of pentafluorophenol and anthranilic acid in a molar ratio of 1:(1-1.2). Specifically, the preparation method of the pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:(1-1.2), and then 0.04-0.06% of concentrated sulfuric acid based on the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C, the reaction is completed after 1-3 hours, and dehydration is carried out for 2 hours to obtain the pentafluorophenol-modified anthranilic acid.

[0008] The structure of pentafluorophenol is as follows: ; The structure of anthranilic acid is as follows: .

[0009] The polyol is one or more of sucrose, ethylene glycol, diethanolamine, diethylene glycol, dipropylene glycol, propylene glycol and glycerol.

[0010] The mass percentage of the pentafluorophenol-modified anthranilic acid in the mixed initiator is 13.93% to 74.34%.

[0011] The composite catalyst is a mixture of catalyst A and catalyst B; catalyst A is one or two of KOH and potassium methoxide; catalyst B is one or more of dimethylacetamide, diethylenetriamine, dimethylethanolamine, and dimethylisopropanolamine. Among them, catalyst B has high catalytic activity in the early stage of the reaction, but the catalytic activity decreases in the later stage of the reaction, and even loses catalytic activity as the reaction time increases. Therefore, the present invention adopts a compound of two catalysts A and B to improve the catalytic activity of the entire reaction process, thereby shortening the production cycle.

[0012] The mass ratio of the catalyst A to the catalyst B is (0.33-0.67):1.

[0013] The added amount of the composite catalyst is 0.22% to 0.39% of the total mass of the mixed initiator and the alkylene oxide.

[0014] The alkylene oxide is one or both of propylene oxide and ethylene oxide.

[0015] The mass ratio of the alkylene oxide to the mixed initiator is (0.33-1.19):1.

[0016] The preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: (1) Add pentafluorophenol-modified anthranilic acid, polyol and composite catalyst into a reaction vessel, add alkylene oxide dropwise at a temperature of 80-85°C and a vacuum degree of -0.08--0.1 MPa to carry out polyether chain extension, and continue the internal pressure reaction for 2-2.5 hours after the feeding is completed to obtain a pentafluorophenol-modified anthranilic acid polyether polyol intermediate; (2) The pentafluorophenol-modified anthranilic acid polyether polyol intermediate is heated to 105-110°C, and alkylene oxide is added dropwise for end-capping synthesis. After the feeding is completed, the internal pressure reaction is continued for 2-2.5 hours to obtain a crude polymer of pentafluorophenol-modified anthranilic acid polyether polyol, and nitrogen is bubbled to obtain pentafluorophenol-modified anthranilic acid polyether polyol; In the step (2), when nitrogen is bubbling to remove residual small molecules, the pressure in the reactor is controlled at -0.09 MPa. After the bubbling is completed, the crude polymer of pentafluorophenol-modified o-aminobenzoic acid polyether polyol is cooled to 85-90°C.

[0017] The mass of the alkylene oxide in step (1) is 22% to 44% of the total mass of the alkylene oxide in step (1) and step (2).

[0018] The application of the pentafluorophenol-modified anthranilic acid polyether polyol is to prepare the pentafluorophenol-modified anthranilic acid polyether polyol into a rigid polyurethane foam, thereby improving its mutual solubility, strength, flame retardancy and thermal insulation performance. The specific steps of the application are the steps of preparing the rigid polyurethane foam: the prepared pentafluorophenol-modified anthranilic acid polyether polyol is mixed with other catalysts, water, a physical foaming agent and a flame retardant additive as component A, and a polymerized MDI polyurethane resin is used as material B, and the ingredients are prepared according to an -NCO index of 1.03, mixed and foamed to obtain a rigid polyurethane foam.

[0019] The pentafluorophenol-modified o-aminobenzoic acid of the present invention is a homemade product, wherein the key step is the esterification reaction of pentafluorophenol and o-aminobenzoic acid. The reaction is carried out in the presence of an acidic catalyst to ensure the high efficiency and selectivity of the reaction. During the reaction, pentafluorophenol and o-aminobenzoic acid are mixed under heating conditions of 220° C., and then 0.04-0.06% sulfuric acid is added as a catalyst to promote the esterification reaction. The reaction is maintained at a temperature under reflux conditions, and the moisture generated during the reaction is removed. After the reaction is completed, pure pentafluorophenol-modified o-aminobenzoic acid is obtained through washing, drying and purification steps. The product is an important intermediate for synthesizing the target polyether polyol, and its structure and purity directly affect the performance of the final product.

[0020] The pentafluorophenol-modified anthranilic acid of the present invention has excellent flame retardancy and rigidity because it contains halogen fluorine and benzene rings in its molecular structure. The modified polyether polyol performs well under high temperature and strong chemical environment, and is particularly suitable for demanding industrial applications. For example, in industries such as automobiles, aerospace, electrical and electronic, and high-performance coatings, the material can be used as an insulating material, a sealant, or an adhesive to provide long-term stable performance. In addition, due to its unique chemical structure, the polyether polyol also has good flame retardancy and can meet increasingly stringent fire safety standards. At the same time, its benzene ring structure can enhance the compressive strength of polyether. In addition, the polyether polyol synthesized using pentafluorophenol-modified anthranilic acid as an initiator also has the advantages of fine pores and low thermal conductivity when preparing polyurethane rigid foam. However, when the mass percentage of pentafluorophenol-modified anthranilic acid in the mixed initiator is too high (more than 55%), it will cause difficulty in stirring due to its solid crystal, affecting normal production.

[0021] Specifically, the preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: (1) The preparation method of pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:(1-1.2), and then 0.04-0.06% of concentrated sulfuric acid based on the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C. The reaction takes 1-3 hours to complete, and dehydration is carried out for 2 hours to obtain pentafluorophenol-modified anthranilic acid.

[0022] (2) Add pentafluorophenol-modified o-aminobenzoic acid, polyol and composite catalyst into the reactor, pressurize to 0.2~0.25MPa for 20min, raise the temperature to 80~85℃ under vacuum negative pressure atmosphere, evacuate to -0.08~-0.1MPa, add alkylene oxide dropwise for polyether chain extension, continue internal pressure reaction for 2~2.5h after the feeding is completed, and obtain pentafluorophenol-modified o-aminobenzoic acid polyether polyol intermediate.

[0023] (3) The pentafluorophenol-modified anthranilic acid polyether polyol intermediate is heated to 105-110°C, and alkylene oxide is added dropwise for end-capping synthesis. After the feeding is completed, the internal pressure reaction is continued for 2-2.5 hours to obtain a pentafluorophenol-modified anthranilic acid polyether polyol crude polymer. The crude polymer is pressurized to 0.2-0.3 MPa with nitrogen filling and the pressure is no longer reduced. The crude polymer of the pentafluorophenol-modified anthranilic acid polyether polyol is cooled to 100-105°C and nitrogen is bubbled to remove residual small molecules. After bubbling for 0.5-1 hour, the temperature is lowered to 85-90°C and the material is discharged to obtain the pentafluorophenol-modified anthranilic acid polyether polyol.

[0024] The present invention firstly makes the polymerization reaction of the mixed initiator and the alkylene oxide at a relatively low temperature, and then raises the temperature to a relatively high temperature to continue the reaction. This is because the activity of small molecule alcohol is relatively high under high temperature environment. Carrying out the reaction under low temperature conditions first is conducive to the full reaction of pentafluorophenol-modified o-aminobenzoic acid and sucrose with the alkylene oxide, thereby preventing the pentafluorophenol-modified o-aminobenzoic acid and sucrose from remaining unreacted.

[0025] Compared with the prior art, the present invention has the following beneficial effects: (1) The preparation method of pentafluorophenol-modified o-aminobenzoic acid polyether polyol of the present invention improves the physical and chemical properties of the polyether polyol through modification treatment, so that the polyether polyol has better comprehensive performance when preparing rigid polyurethane foam.

[0026] (2) The pentafluorophenol-modified o-aminobenzoic acid polyether polyol prepared by the present invention is used to prepare rigid polyurethane foam, which improves the flame retardant properties of the rigid foam material, effectively reduces the risk of fire, and prolongs the service life of the rigid foam material at high temperatures; it also enhances the high compressive strength of the rigid foam material, so that it can still maintain the integrity of the structure under heavy pressure, and is suitable for application scenarios that require high load-bearing capacity.

[0027] (3) The pentafluorophenol-modified o-aminobenzoic acid polyether polyol prepared by the present invention is used to prepare rigid polyurethane foam, which effectively reduces the thermal conductivity of the rigid foam material and improves its thermal insulation performance. DETAILED DESCRIPTION

[0028] The present invention will be further described below in conjunction with specific embodiments.

[0029] All raw materials used in the examples are commercially available unless otherwise specified. The concentrated sulfuric acid is a product labeled as concentrated sulfuric acid on the market, which is concentrated sulfuric acid in the popular sense without treatment or dilution.

[0030] Example 1 The preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: The preparation method of pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:1, and then concentrated sulfuric acid of 0.04% of the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C. The reaction is completed after 1 hour, and dehydration is carried out for 2 hours to obtain pentafluorophenol-modified anthranilic acid. (2) 300g of pentafluorophenol-modified anthranilic acid, 180g of sucrose, 100g of diethanolamine, 30g of diethylene glycol, 30g of glycerol, 2g of KOH, and 3g of diethylenetriamine are added to the reaction kettle, and the pressure is filled to 0.25MPa for leak test for 20 minutes, and the temperature is raised to 80°C under vacuum negative pressure atmosphere, and the vacuum is evacuated to -0.09MPa, and 200g of ethylene oxide is added dropwise for polyether chain extension. After the feeding is completed, the internal pressure reaction is continued for 2 hours to obtain pentafluorophenol-modified anthranilic acid polyether polyol intermediate; (3) The temperature of the pentafluorophenol-modified anthranilic acid polyether polyol intermediate was raised to 105°C, and 444 g of propylene oxide was continuously added dropwise for end-capping synthesis. After the feeding was completed, the temperature was kept high and the internal pressure reaction was continued for 2.5 h. The reactor was pressurized to 0.25 MPa with nitrogen and the pressure in the reactor did not decrease any more. The temperature was lowered to 100°C and nitrogen was bubbled to remove residual small molecules in the product. After bubbling for 0.5 h, the temperature was lowered to 85°C and the material was discharged to obtain pentafluorophenol-modified anthranilic acid polyether polyol.

[0031] Example 2 The preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: (1) The preparation method of pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:1.2, and then 0.06% of concentrated sulfuric acid based on the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C. The reaction lasts for 3 hours, and dehydration is carried out for 2 hours to obtain pentafluorophenol-modified anthranilic acid.

[0032] (2) Add 150g of pentafluorophenol-modified o-aminobenzoic acid, 162g of sucrose, 50g of diethanolamine, 54g of diethylene glycol, 21g of propylene glycol, 1.1g of potassium methoxide, 0.9g of dimethylacetamide, and 0.8g of dimethylethanolamine into the reactor, pressurize to 0.25MPa for leak test for 20min, raise the temperature to 85°C under vacuum, evacuate to -0.08MPa, add 221g of ethylene oxide dropwise for polyether chain extension, and continue the internal pressure reaction for 2h after the feeding is completed to obtain a pentafluorophenol-modified o-aminobenzoic acid polyether polyol intermediate; (3) The temperature of the pentafluorophenol-modified anthranilic acid polyether polyol intermediate was raised to 110°C, and 286 g of propylene oxide was continuously added dropwise for end-capping synthesis. After the feeding was completed, the temperature was kept high and the internal pressure reaction was continued for 2.5 hours. The reactor was pressurized to 0.25 MPa with nitrogen and the pressure in the reactor did not decrease any more. The temperature was lowered to 105°C and nitrogen was bubbled to remove residual small molecules in the product. After bubbling for 2.5 hours, the temperature was lowered to 85°C and the material was discharged to obtain pentafluorophenol-modified anthranilic acid polyether polyol.

[0033] Example 3 The preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: (1) The preparation method of pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:1.1, and then 0.05% of concentrated sulfuric acid based on the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C. The reaction lasts for 2 hours, and dehydration is carried out for 2 hours to obtain pentafluorophenol-modified anthranilic acid.

[0034] (2) Add 134 g of pentafluorophenol-modified o-aminobenzoic acid, 201 g of sucrose, 81 g of diethanolamine, 146 g of dipropylene glycol, 0.41 g of potassium methoxide, 0.5 g of KOH, and 2.09 g of dimethyl isopropanolamine into the reactor, pressurize to 0.25 MPa for leak test for 20 min, raise the temperature to 85 ° C under vacuum negative pressure atmosphere, evacuate to -0.08 MPa, add 117 g of ethylene oxide dropwise for polyether chain extension, and continue the internal pressure reaction for 2.5 h after the feeding is completed to obtain pentafluorophenol-modified o-aminobenzoic acid polyether polyol intermediate; (3) The temperature of the pentafluorophenol-modified anthranilic acid polyether polyol intermediate was raised to 110°C, and 425 g of propylene oxide was continuously added dropwise for end-capping synthesis. After the feeding was completed, the temperature was kept high and the internal pressure reaction was continued for 2 h. The reactor was pressurized to 0.3 MPa with nitrogen and the pressure in the reactor did not decrease any more. The temperature was lowered to 105°C and nitrogen was bubbled to remove residual small molecules in the product. After bubbling for 2.5 h, the temperature was lowered to 90°C and the material was discharged to obtain pentafluorophenol-modified anthranilic acid polyether polyol.

[0035] Example 4 The preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: (1) The preparation method of pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:1, and then 0.05% of concentrated sulfuric acid based on the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C. The reaction lasts for 2 hours, and dehydration is carried out for 2 hours to obtain pentafluorophenol-modified anthranilic acid.

[0036] (2) Add 710g of pentafluorophenol-modified o-aminobenzoic acid, 314g of sucrose, 66g of diethanolamine, 30g of ethylene glycol, 1.4g of KOH, 1.4g of dimethylethanolamine, and 1.2g of dimethylisopropanolamine into the reactor, pressurize to 0.25MPa for leak test for 20min, raise the temperature to 85°C under vacuum negative pressure atmosphere, evacuate to -0.09MPa, add 232g of propylene oxide dropwise for polyether chain extension, and continue the internal pressure reaction for 2h after the feeding is completed to obtain pentafluorophenol-modified o-aminobenzoic acid polyether polyol intermediate; (3) The temperature of the pentafluorophenol-modified anthranilic acid polyether polyol intermediate was raised to 110°C, and 455 g of propylene oxide was continuously added dropwise for end-capping synthesis. After the feeding was completed, the temperature was kept high and the internal pressure reaction was continued for 2 h. The reactor was pressurized to 0.25 MPa with nitrogen and the pressure in the reactor did not decrease any more. The temperature was lowered to 100°C and nitrogen was bubbled to remove residual small molecules in the product. After bubbling for 2 h, the temperature was lowered to 85°C and the material was discharged to obtain pentafluorophenol-modified anthranilic acid polyether polyol.

[0037] Example 5 The preparation method of the pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: (1) The preparation method of pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:1, and then 0.05% of concentrated sulfuric acid based on the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C. The reaction lasts for 2 hours, and dehydration is carried out for 2 hours to obtain pentafluorophenol-modified anthranilic acid.

[0038] (2) Add 710g of pentafluorophenol-modified o-aminobenzoic acid, 245g of sucrose, 1.4g of KOH, 1.4g of dimethylethanolamine, and 1.2g of dimethylisopropanolamine into the reactor, pressurize to 0.25MPa for 20min, raise the temperature to 85°C under vacuum, evacuate to -0.09MPa, add 107g of propylene oxide dropwise for polyether chain extension, and continue the internal pressure reaction for 2h after the feeding is completed to obtain a pentafluorophenol-modified o-aminobenzoic acid polyether polyol intermediate; (3) The temperature of the pentafluorophenol-modified anthranilic acid polyether polyol intermediate was raised to 110°C, and 210 g of propylene oxide was continuously added dropwise for end-capping synthesis. After the feeding was completed, the temperature was kept high and the internal pressure reaction was continued for 2 h. The reactor was pressurized to 0.25 MPa with nitrogen and the pressure in the reactor did not decrease any more. The temperature was lowered to 100°C and nitrogen was bubbled to remove residual small molecules in the product. After bubbling for 2 h, the temperature was lowered to 85°C and the material was discharged to obtain pentafluorophenol-modified anthranilic acid polyether polyol.

[0039] Comparative Example 1 A method for preparing a polyether polyol comprises the following steps: adding 366g of sucrose, 53g of solid sorbitol, 364g of diethylene glycol, 212g of palm oil and 9g of a fatty amine catalyst into a reaction kettle, pressurizing to 0.2MPa for leak testing for 20min, heating to 105°C under vacuum negative pressure atmosphere, while maintaining the nitrogen atmosphere pressure in the kettle at 0.13MPa, dripping 1094g of propylene oxide, and after the dripping of propylene oxide is completed, continuing to keep the temperature for reaction for 3h until the pressure in the kettle no longer decreases, cooling to 100°C, bubbling with nitrogen to remove residual small molecular substances in the product, cooling to 80°C after bubbling for 2h, and discharging to obtain the polyether polyol.

[0040] Comparative Example 2 A method for preparing a polyether polyol comprises the following steps: Add 352g sucrose, 359g diethylene glycol and 2g chromium acetylacetonate catalyst into the reaction kettle, pressurize to 0.25MPa for leak test for 20min, raise the temperature to 120℃ under vacuum negative pressure atmosphere, while maintaining the nitrogen atmosphere pressure at 0.13±0.02MPa in the kettle, add 952g propylene oxide dropwise, after the addition of propylene oxide is completed, continue to keep warm and react for 3h until the pressure in the kettle no longer decreases, cool to 100℃, bubble with nitrogen to remove residual small molecules in the product, cool to 80℃ after bubbling for 2h, discharge to obtain polyether polyol.

[0041] Comparative Example 3 A method for preparing a modified polyether polyol (deleting pentafluorophenol-modified anthranilic acid, but controlling the functionality and hydroxyl value to be consistent with Example 1, thereby reducing the addition of sugar and alkylene oxide), comprising the following steps: (1) Add 73g sucrose, 100g diethanolamine, 30g diethylene glycol, 30g glycerol, 2g KOH, and 3g diethylenetriamine into a reactor, pressurize to 0.25MPa for 20min, raise the temperature to 80°C under vacuum, evacuate to -0.09MPa, add 158g ethylene oxide dropwise for polyether chain extension, and continue the internal pressure reaction for 2h after the feeding is completed to obtain a pentafluorophenol-modified o-aminobenzoic acid polyether polyol intermediate; (2) The temperature of the pentafluorophenol-modified anthranilic acid polyether polyol intermediate was raised to 105°C, and 350 g of propylene oxide was continuously added dropwise for end-capping synthesis. After the feeding was completed, the temperature was kept high and the internal pressure reaction was continued for 2.5 h. The reactor was pressurized to 0.25 MPa with nitrogen and the pressure in the reactor did not decrease any more. The temperature was lowered to 100°C and nitrogen was bubbled to remove residual small molecules in the product. After bubbling for 0.5 h, the temperature was lowered to 85°C and the modified polyether polyol was discharged.

[0042] Comparative Example 4 A method for preparing pentafluorophenol-modified anthranilic acid polyether polyol comprises the following steps: (1) The preparation method of pentafluorophenol-modified anthranilic acid is as follows: pentafluorophenol and anthranilic acid are mixed in a molar ratio of 1:1, and then concentrated sulfuric acid in an amount of 0.04% of the total mass of pentafluorophenol and anthranilic acid is added, and an esterification reaction is carried out at 220°C. The reaction lasts for 1 hour, and dehydration is carried out for 2 hours to obtain pentafluorophenol-modified anthranilic acid.

[0043] (2) Add 300g of pentafluorophenol-modified o-aminobenzoic acid, 180g of sucrose, 100g of diethanolamine, 30g of diethylene glycol, 30g of glycerol, and 5g of diethylenetriamine into the reactor, pressurize to 0.25MPa for leak test for 20min, raise the temperature to 80°C under vacuum negative pressure atmosphere, evacuate to -0.09MPa, add 200g of ethylene oxide dropwise for polyether chain extension, and continue the internal pressure reaction for 2h after the feeding is completed to obtain pentafluorophenol-modified o-aminobenzoic acid polyether polyol intermediate; (3) The temperature of the pentafluorophenol-modified anthranilic acid polyether polyol intermediate was raised to 105°C, and 444 g of propylene oxide was continuously added dropwise for end-capping synthesis. After the feeding was completed, the temperature was kept high and the internal pressure reaction was continued for 2.5 h. The reactor was pressurized to 0.25 MPa with nitrogen and the pressure in the reactor did not decrease any more. The temperature was lowered to 100°C and nitrogen was bubbled to remove residual small molecules in the product. After bubbling for 0.5 h, the temperature was lowered to 85°C and the material was discharged to obtain pentafluorophenol-modified anthranilic acid polyether polyol.

[0044] Performance Testing The indicators of the polyether polyols obtained in Examples 1 to 5 and Comparative Examples 1 to 4 are shown in Table 1.

[0045] Table 1 Index table of polyether polyols of Examples 1 to 5 and Comparative Examples 1 to 4

[0046] The polyether polyols obtained in Examples 1 to 5 and Comparative Examples 1 to 4 were prepared according to Table 2 to obtain rigid polyurethane foam material A; wherein the catalyst used was MAYCAT PC8 from Jiangsu Meside Chemical Co., Ltd., the flame retardant used was tris (2-chloroethyl) phosphate (TCEP), and the physical foaming agent used was 141b. Material A and material B were prepared according to an -NCO index of 1.03, mixed evenly, and foamed to obtain a polyurethane foam sample. The amount of each raw material in Table 2 is in parts by mass.

[0047] Table 2 Ratio of rigid polyurethane foam material A in Examples 1 to 5 and Comparative Examples 1 to 4

[0048] The rigid polyurethane foam material A obtained in Examples 1 to 5 and Comparative Examples 1 to 4 was mixed with material B to prepare a rigid polyurethane foam, wherein material B was PM200 produced by Wanhua Chemical Group Co., Ltd. The obtained rigid polyurethane foam was subjected to performance tests, and the results are shown in Table 3.

[0049] Among them, the strength is in accordance with the standard GB / T8813-2020; the thermal conductivity is in accordance with the standard QB / T3806-1999, the sample size is 200mm×200mm×20mm, and the thermal conductivity is measured by a thermal conductivity tester; miscibility: the mass fraction of cyclopentane that is completely miscible with 100 parts of polyether polyol. The oxygen index is tested in accordance with the standard GB / T2918-1988. Table 3 Performance test table of rigid polyurethane foam of Examples 1 to 5 and Comparative Examples 1 to 4

[0050] It can be seen from Table 3 that the mutual solubility, strength, flame retardancy and thermal insulation properties of the rigid polyurethane foam prepared from the pentafluorophenol-modified o-aminobenzoic acid polyether polyol of the present invention are significantly improved.

Claims

1. A pentafluorophenol-modified anthranilic acid polyether polyol, characterized in that: It is obtained by using pentafluorophenol-modified anthranilic acid and polyol as mixed initiators, and polymerizing with alkylene oxide under the action of a composite catalyst; The pentafluorophenol-modified anthranilic acid is prepared by esterification reaction of pentafluorophenol and anthranilic acid in a molar ratio of 1:(1-1.2).

2. The pentafluorophenol-modified o-aminobenzoic acid polyether polyol according to claim 1, characterized in that: The polyol is one or more of sucrose, ethylene glycol, diethanolamine, diethylene glycol, dipropylene glycol, propylene glycol and glycerol.

3. The pentafluorophenol-modified o-aminobenzoic acid polyether polyol according to claim 1, characterized in that: The mass percentage of the pentafluorophenol-modified anthranilic acid in the mixed initiator is 13.93% to 74.34%.

4. The pentafluorophenol-modified o-aminobenzoic acid polyether polyol according to claim 1, characterized in that: The composite catalyst is a mixture of catalyst A and catalyst B; catalyst A is one or two of KOH and potassium methoxide; catalyst B is one or more of dimethylacetamide, diethylenetriamine, dimethylethanolamine and dimethylisopropanolamine.

5. The pentafluorophenol-modified o-aminobenzoic acid polyether polyol according to claim 4, characterized in that: The mass ratio of the catalyst A to the catalyst B is (0.33-0.67):

1.

6. The pentafluorophenol-modified anthranilic acid polyether polyol according to claim 1, characterized in that: The added amount of the composite catalyst is 0.22% to 0.39% of the total mass of the mixed initiator and the alkylene oxide.

7. The pentafluorophenol-modified anthranilic acid polyether polyol according to claim 1, characterized in that: The alkylene oxide is one or both of propylene oxide and ethylene oxide.

8. The pentafluorophenol-modified o-aminobenzoic acid polyether polyol according to claim 1, characterized in that: The mass ratio of the alkylene oxide to the mixed initiator is (0.33-1.19):

1.

9. A method for preparing the pentafluorophenol-modified anthranilic acid polyether polyol according to any one of claims 1 to 8, characterized in that: The following steps are involved: (1) Add pentafluorophenol-modified anthranilic acid, polyol and composite catalyst into a reaction vessel, add alkylene oxide dropwise at a temperature of 80-85°C and a vacuum degree of -0.08--0.1 MPa to carry out polyether chain extension, and continue the internal pressure reaction for 2-2.5 hours after the feeding is completed to obtain a pentafluorophenol-modified anthranilic acid polyether polyol intermediate; (2) The pentafluorophenol-modified anthranilic acid polyether polyol intermediate is heated to 105-110°C, and alkylene oxide is added dropwise for end-capping synthesis. After the feeding is completed, the internal pressure reaction is continued for 2-2.5 hours to obtain a crude polymer of pentafluorophenol-modified anthranilic acid polyether polyol, and nitrogen is bubbled to obtain pentafluorophenol-modified anthranilic acid polyether polyol; The mass of the alkylene oxide in step (1) is 22% to 44% of the total mass of the alkylene oxide in step (1) and step (2).

10. An application of the pentafluorophenol-modified anthranilic acid polyether polyol according to any one of claims 1 to 8, characterized in that: Pentafluorophenol-modified o-aminobenzoic acid polyether polyol is used to prepare rigid polyurethane foam to improve its mutual solubility, strength, flame retardancy and thermal insulation properties.

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