A preparation method of polyaryletherketone

Abstract

The present invention relates to the technical field of high-performance polymer synthesis, and specifically to a method for preparing polyaryletherketone, wherein the preparation method comprises the following steps: S1, under inert gas conditions, adding dihalogenated dibenzophenone and bisphenol fluorene to a solvent and mixing them uniformly, adding alkali metal carbonate, and reacting under heating conditions to obtain an oligomer; S2, adding aromatic diphenols to the system of step S1 in batches, and performing a programmed temperature reaction to obtain a block copolymer; S3, adding a capping agent to the system to perform an end-capping reaction, and obtaining polyaryletherketone by post-processing after the reaction is completed. The preparation method of polyaryletherketone described in the present invention adopts a gradient segmented feeding method and develops a polymerization process of low-temperature pre-condensation and high-temperature chain extension copolymerization, with controllable reaction rate, uniform sequence distribution, and stable product performance. In addition, the preparation method described in the present invention can effectively reduce energy consumption and is more conducive to industrial production.

Description

Technical Field

[0001] The invention relates to a preparation method of polyaryletherketone, belonging to the technical field of high-performance polymer synthesis. Background Art

[0002] Polyaryletherketone (PAEK) is a semi-crystalline thermoplastic material with excellent properties such as high temperature resistance, high strength, high modulus, high insulation, corrosion resistance, good dimensional stability and easy processing. It is an engineering plastic with excellent comprehensive performance and is widely used in electronics, machinery, automobiles, aircraft, food, medical care, aerospace and other fields.

[0003] Traditional preparation methods for polyaryletherketones (PEEKs) are mainly divided into nucleophilic substitution and electrophilic substitution. With the development of industrialization, the nucleophilic substitution method has gradually become dominant due to its advantages such as excellent purity and crystallinity of the prepared products, becoming the core method for the industrial production of polyaryletherketones. Patent applications with publication numbers US4176222A, US4320224A, and US4331798A all describe the use of the nucleophilic substitution method to prepare polyaryletherketones. That is, a variety of aromatic polyethers containing -SO2- or -CO- groups (collectively referred to as polyaryletherketone materials) were prepared using different bisphenols and aromatic dihalogenated compounds. Subsequently, the effects of changing factors such as alkali metal salts and solvents on the properties of polyaryletherketone materials were explored. With the in-depth research and development of polyaryletherketones, polyetheretherketone (PEEK) has stood out from many polyaryletherketone materials due to its excellent performance, becoming one of the high-performance polymers that countries are currently competing to develop. Taking the nucleophilic substitution preparation method of PEEK as an example, its reaction process is as follows:

[0004] ;

[0005] Where X represents halogen (F, Cl, Br, etc.); R1 represents C 6-30 Aromatic hydrocarbon groups and their halogenated derivatives, etc.; R2 represents a monovalent C 1-13 Organic groups, phenyl, biphenyl, etc.

[0006] The above-mentioned traditional methods usually involve two or more reactants reacting in an equimolar ratio of functional groups or with a slight excess of aromatic dihalogenated compounds. The reaction has problems such as harsh synthesis conditions, high energy consumption, high cost, and certain pollution of by-products. First of all, in terms of synthesis, traditional polyetheretherketone has strict requirements on the purity of raw materials, inert atmosphere, temperature control and reaction time during preparation, which makes the preparation conditions of the product very harsh. Secondly, the reaction temperature currently disclosed is mostly not lower than 310°C. The high reaction temperature and long reaction time greatly increase energy consumption and are very unfavorable for industrial production. Finally, there is the issue of recycling. Due to the cost of raw materials, the solvent and by-products need to be recycled after the reaction. Therefore, the post-processing will involve the use of a large amount of organic reagents, which will eventually produce a large amount of waste solvents and alkaline wastewater. The cost of treating the three wastes is high and the environment is polluted.

[0007] Currently, the mainstream development direction of polyaryletherketone (PEK) is not only to optimize the types of raw materials used in traditional preparation methods and the preparation process, but also to improve the performance of polyaryletherketone by introducing new comonomers. For example, patent publication number CN100582133C discloses a method for preparing polyetheretherketone (PEEK). The new polyaryletherketone product is prepared by copolymerizing biphenol, hydroquinone, and 4,4'-difluorobenzophenone. Compared with traditional PEEK materials, this product has a higher melting point and melt viscosity, but its mechanical strength is inferior. Patent publication number CN101245139B discloses a method for preparing polyetherketone and polyetheretherketone terpolymers. 4,4'-dihydroxybenzophenone, hydroquinone, and 4,4'-difluorobenzophenone are used to copolymerize to prepare fluorine-terminated polyaryletherketone (PEEK). This material has high thermal stability, but the preparation temperature is high (requiring a reaction temperature of 320°C for 3-5 hours), and the energy consumption is high, which is not conducive to large-scale production. Patent application publication number CN116515101A discloses a semi-crystalline biphenyl copolymer polyetheretherketone resin and a preparation method thereof. In the preparation method, cyclopentane is used as a solvent, xylene is used as a water-carrying agent, and bisphenol fluorene, biphenol and 4,4'-difluorobenzophenone are used to prepare a high-temperature resistant polyaryletherketone. The preparation method has a relatively low polymerization temperature and a relatively simple post-processing process, but the reaction is more demanding. During the dehydration stage, due to the relatively high boiling point of the mixture of xylene and cyclopentane, it is difficult to completely remove the xylene, resulting in a low conversion rate in the final reaction. Secondly, when introducing the bisphenol fluorene monomer, due to its large steric effect, it is often difficult to evenly graft it into the main chain, which will also affect the performance of the final product.

[0008] Therefore, it is of great value to develop a method for preparing polyaryletherketone materials that can be produced with low energy consumption and high efficiency, has a wider range of applications and is easy to process. Summary of the Invention

[0009] The present invention addresses the deficiencies in the prior art and provides a method for preparing polyaryletherketone. The method has mild process conditions, low energy consumption, and is suitable for industrial applications. In addition, the prepared polyaryletherketone has higher mechanical strength, chemical corrosion resistance, and processability.

[0010] The technical solution of the present invention to solve the above technical problems is as follows: a preparation method of polyaryletherketone, the preparation method is:

[0011] S1. Under inert gas conditions, dihalogenated benzophenone and bisphenol fluorene are added to a solvent and mixed evenly, and an alkali metal carbonate is added and reacted under heating conditions to obtain an oligomer;

[0012] S2, adding aromatic diphenols to the system of step S1 in batches, and performing a temperature-programmed reaction to obtain a block copolymer;

[0013] S3. Adding a capping agent to the system to carry out a capping reaction, and after the reaction is completed, post-processing is performed to obtain polyaryletherketone.

[0014] Furthermore, the dihalogenated benzophenone is at least one of 2,4'-difluorobenzophenone, 4,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone, and 4,4'-dibromobenzophenone;

[0015] The aromatic diphenol is at least one of hydroquinone, resorcinol, biphenol, bisphenol A and phenolphthalein.

[0016] Furthermore, the molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the dihalogenated benzophenone is 1:(0.95-1.15); and the molar ratio of the aromatic diphenol to the bisphenol fluorene is 1:(0.1-0.8).

[0017] Furthermore, the molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:(0.98-1.30);

[0018] The alkali metal carbonate is at least one of potassium carbonate, sodium carbonate and cesium carbonate.

[0019] Furthermore, the alkali metal carbonate is a combination of sodium carbonate and potassium carbonate, and the molar ratio of the sodium carbonate to potassium carbonate is 1:(0.01-0.5).

[0020] Furthermore, the solvent is any one of sulfolane, N,N-dimethylformamide, N,N-dimethylacetamide, diphenyl sulfone, dimethyl sulfoxide, and N-methylpyrrolidone.

[0021] Furthermore, the end-capping agent is at least one of 4-fluorobenzophenone, 4-chlorobenzophenone, and 4-fluorobiphenyl;

[0022] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is (0.01-0.05):1.

[0023] Furthermore, in step S1, the reaction temperature is 150-180° C., and the reaction time is 0.5-2 h.

[0024] Furthermore, in step S2, the aromatic diphenol is added to the reaction system in three batches. After the first batch of aromatic diphenol is added to the system, the temperature is raised to 180~230℃ and the reaction is carried out for 0.5~2h; after the second batch of aromatic diphenol is added to the system, the temperature is raised to 230~270℃ and the reaction is carried out for 0.5~2h; after the third batch of aromatic diphenol is added to the system, the temperature is raised to 270~300℃ and the reaction is carried out for 0.5~2h.

[0025] Furthermore, in step S3, the post-processing operation method is: after the reaction is completed, the product is poured into cold water to cool and solidify, the solid is taken and crushed, and then washed and dried to obtain the polyaryletherketone product.

[0026] The beneficial effects of the present invention are:

[0027] (1) Compared with conventional processes, the preparation method of polyaryletherketone according to the present invention adopts a gradient step-by-step feeding method and develops a polymerization process of low-temperature pre-condensation and high-temperature chain extension copolymerization. This avoids the problems of difficult-to-control reaction rate, wide molecular weight distribution, and large differences in the reactivity of bisphenol fluorene and hydroquinone, which leads to uneven sequence distribution and poor performance stability of the final product. In addition, the polymerization reaction temperature (270-300°C) of the preparation method according to the present invention is more than 10% lower than that of the conventional PAEK preparation process (300-340°C), which can effectively reduce energy consumption. Therefore, the preparation method according to the present invention is more conducive to industrial production.

[0028] (2) Compared with the traditional method, the preparation method of polyaryletherketone described in the present invention introduces bisphenol fluorene as a block comonomer. The fluorene ring of bisphenol fluorene can limit the free rotation of the polymer chain segment, reduce the thermal motion of the molecular chain at high temperature, enhance the rigidity of the molecular chain, and thus improve the thermal stability of the material. Secondly, the steric hindrance of the fluorene ring increases the distance between the molecular chains, reduces the interchain slip, and can improve the tensile strength and creep resistance of the product. In addition, the hydrophobic group of the fused benzene ring of the fluorene ring can reduce the penetration of polar solvent molecules (such as concentrated sulfuric acid, DMF) into the polymer matrix, thereby improving the chemical corrosion resistance of the product. Finally, by precisely controlling the bisphenol fluorene content in the molecular chain (10%-70%), the rigidity and toughness of the material can be balanced, truly achieving full adaptation of a material in multiple different fields.

[0029] (3) Compared with traditional polyaryletherketones (such as PEEK), the polyaryletherketone products prepared by the preparation method of the present invention have higher mechanical strength (tensile strength ≥120 MPa, tensile modulus ≥4.5 GPa) and chemical corrosion resistance (strength retention rate in strong acid / strong alkali environment increased from 82% to 95%) while maintaining excellent high temperature resistance (thermal decomposition temperature ≥550°C) and wear resistance. In downstream applications, efficient injection molding of the material can be achieved by adjusting the processing temperature (350~380°C) and screw speed (60~80 rpm). Products with different performance can also be produced by adjusting the proportion of bisphenol A introduced in the preparation method, flexibly adapting to different application scenarios (such as electronic packaging parts requiring low melt viscosity, chemical corrosion protection requiring high acid resistance and stability, etc.). BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 Comparison of tensile curves of the polyaryletherketone products of Example 1 and Comparative Example 1;

[0031] Figure 2 This is the TGA curve of the polyaryletherketone prepared in Example 1. DETAILED DESCRIPTION

[0032] The present invention can be implemented in many other ways than those described herein, and those skilled in the art can make similar improvements without violating the scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which the present invention belongs. The terms used are only for describing specific embodiments and are not intended to limit the present invention.

[0034] A preparation method of polyaryletherketone, the preparation method comprising:

[0035] S1. Under inert gas conditions, dihalogenated benzophenone and bisphenol fluorene are added to a solvent, the temperature is raised until all monomers are melted, and an alkali metal carbonate is added, and the mixture is stirred under heating to react to obtain an oligomer;

[0036] S2, adding aromatic diphenols to the system of step S1 in batches, and performing a programmed temperature-raising and stirring reaction to obtain a block copolymer;

[0037] S3. Adding a capping agent to the system to carry out a capping reaction, and after the reaction is completed, post-processing is performed to obtain polyaryletherketone.

[0038] Specifically, the dihalogenated benzophenone is at least one of 2,4'-difluorobenzophenone, 4,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone, and 4,4'-dibromobenzophenone;

[0039] The aromatic diphenol is at least one of hydroquinone, resorcinol, biphenol, bisphenol A and phenolphthalein.

[0040] Preferably, the dihalogenated benzophenone is 4,4'-difluorobenzophenone, and the aromatic diphenol is hydroquinone.

[0041] Specifically, the molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the dihalogenated benzophenone is 1:(0.95-1.15); the molar ratio of the aromatic diphenol to the bisphenol fluorene is 1:(0.1-0.8).

[0042] Preferably, the molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the dihalogenated benzophenone is 1:(0.99-1.05); the molar ratio of the aromatic diphenol to the bisphenol fluorene is 1:(0.1-0.7).

[0043] Specifically, the molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:(0.98-1.30);

[0044] The alkali metal carbonate is at least one of potassium carbonate, sodium carbonate and cesium carbonate.

[0045] Preferably, the molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:(0.99-1.20).

[0046] Preferably, the alkali metal carbonate is a combination of sodium carbonate and potassium carbonate, and the molar ratio of sodium carbonate to potassium carbonate is 1:(0.01-0.5).

[0047] Specifically, the solvent is any one of sulfolane, N,N-dimethylformamide, N,N-dimethylacetamide, diphenyl sulfone, dimethyl sulfoxide, and N-methylpyrrolidone.

[0048] Preferably, the solvent is sulfolane.

[0049] Specifically, the end-capping agent is at least one of 4-fluorobenzophenone, 4-chlorobenzophenone, and 4-fluorobiphenyl;

[0050] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is (0.01-0.05):1.

[0051] Preferably, the capping agent is 4-fluorobenzophenone.

[0052] Specifically, in step S1, the reaction temperature is 150-180° C., and the reaction time is 0.5-2 h.

[0053] Specifically, in step S2, the aromatic diphenol is added to the reaction system in three batches. After the first batch of aromatic diphenol is added to the system, the temperature is raised to 180~230℃ and the reaction is carried out for 0.5~2h; after the second batch of aromatic diphenol is added to the system, the temperature is raised to 230~270℃ and the reaction is carried out for 0.5~2h; after the third batch of aromatic diphenol is added to the system, the temperature is raised to 270~300℃ and the reaction is carried out for 0.5~2h.

[0054] Specifically, in step S3, the reaction temperature for adding the end-capping agent to carry out the reaction is 140-330° C., and the reaction time is 0.5-3 h.

[0055] Preferably, in step S3, the reaction temperature for adding the end-capping agent to carry out the reaction is 250-330° C., and the reaction time is 0.5-1 h.

[0056] Specifically, in step S3, the post-processing operation method is: after the reaction is completed, pour the product into cold water to cool and solidify, take the solid and grind it, wash and dry it to obtain the polyaryletherketone product.

[0057] More specifically, the post-processing operation process includes: crushing, washing, filtering, and drying to obtain a powdery finished product of polyaryletherketone, and then melt-extruding, air-cooling, and pelletizing to obtain a granular finished product of polyaryletherketone.

[0058] The filtration method includes but is not limited to pressure filtration, vacuum filtration, and centrifugal filtration, preferably pressure filtration; the washing solvent includes but is not limited to methanol, toluene, xylene, ethanol, ether, isopropanol, acetone and water, preferably acetone and water; during washing, 2 to 3 times the amount (based on the weight of the washed crude product) of acetone and water are used in sequence for multiple reflux washings until the solvent and by-products are completely removed, and then the purified product is placed in an oven for drying.

[0059] The drying method is normal pressure drying or negative pressure drying, preferably normal pressure drying; the drying time is 0.5 to 12 hours, preferably 3 to 5 hours; the drying temperature is 80 to 200° C., preferably 150 to 200° C.

[0060] Specifically, the inert gas may be selected from one or more of nitrogen, helium, neon, argon, etc., preferably nitrogen.

[0061] Specifically, the structure of the polyaryletherketone is as follows, but is not limited to the following:

[0062] ;

[0063] Wherein, n and m are integers ranging from 1 to 200 respectively.

[0064] n is preferably an integer of 80 to 200, and m is preferably an integer of 1 to 80.

[0065] In the following examples, the performance evaluation methods and standards for polyaryletherketone products are as follows:

[0066] (1) The weight average molecular weight (Mw) and the polydispersity index (PDI) of the polyaryletherketone are obtained by gel permeation chromatography (GPC) after dissolution in dichloroacetic acid at 120°C. The Mw range is ≥10,000 Daltons, preferably ≥20,000 Daltons, and more preferably ≥30,000 Daltons; the PDI range is ≤2.00, preferably ≤1.50, and more preferably ≤1.20.

[0067] (2) The thermal decomposition temperature (Td(1%)) of the polyaryletherketone is tested using a thermogravimetric analyzer (TGA) according to ASTM E1131, and the Tg range is ≥500.0°C, preferably ≥530.0°C, and more preferably ≥550.0°C.

[0068] (3) The tensile strength, tensile modulus and elongation at break of the polyaryletherketone are tested using a universal material tester in accordance with ASTM D638. The tensile strength range is ≥70.0 MPa, preferably ≥90.0 MPa, and more preferably ≥100.0 MPa; the tensile modulus range is ≥3000.0 MPa, preferably ≥3500.0 MPa, and more preferably ≥4000.0 MPa; and the elongation at break is ≥1.0%, preferably ≥10.0%, and more preferably ≥20.0%.

[0069] (4) The melt flow index of the polyaryletherketone is tested according to standard ASTM D1238 using a melt flow meter under conditions of a 5 kilogram (kg) weight and a temperature of 380°C. The melt flow index range is 3.0 to 30.0 g / 10 min, preferably 5.0 to 25.0 g / 10 min, and more preferably 8.0 to 15.0 g / 10 min.

[0070] (5) The acid resistance strength retention rate of the polyaryletherketone is a tensile strength performance test performed by immersing a test specimen in 98% concentrated sulfuric acid at room temperature (23±2°C, 50±10% humidity) for 48 hours according to standard ASTM D543. The acid resistance strength retention rate ranges from 50% to 99%, preferably from 80% to 99%, and more preferably from 90% to 99%.

[0071] The key raw materials involved in the examples are as follows (the remaining raw materials are common commercially available industrial products):

[0072] (1) 4,4'-Difluorobenzophenone, purity ≥99.0%, purchased from Kangda New Materials Co., Ltd.

[0073] (2) Hydroquinone, purity ≥99.5%, purchased from Jinan Century Tongda Chemical Co., Ltd.

[0074] (3) Bisphenol fluorene, purity ≥98.0%, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0075] (4) Diphenyl sulfone, purity ≥99.5%, purchased from Shandong Dibeck Bioengineering Co., Ltd.

[0076] (5) 4-Fluorobenzophenone, purity ≥99.0%, purchased from Shanghai Aladdin Biochemical Technology Co., Ltd.

[0077] (6) Sodium carbonate, purity ≥99.0%, purchased from Sinopharm Chemical Reagent Co., Ltd.

[0078] (7) Potassium carbonate, purity ≥99.0%, purchased from Sinopharm Chemical Reagent Co., Ltd.

[0079] Example 1

[0080] A preparation method of polyaryletherketone, the preparation method comprising:

[0081] S1. Evacuate a 2L three-necked flask equipped with a mechanical stirrer, thermometer, and water separator, then fill it with high-purity nitrogen (≥99.99%). Repeat the evacuation three or more times to fully replace the air atmosphere in the system with a nitrogen atmosphere, and continue to introduce a certain flow of nitrogen to maintain it. Add 500g of diphenyl sulfone (2.29mol), 4,4'-difluorobenzophenone (1.00mol), and bisphenol fluorene (0.10mol) to the three-necked flask. Heat to 160°C until they are completely melted, then add sodium carbonate (0.70mol) and potassium carbonate (0.35mol), and react at 160°C for 1h to obtain an oligomer.

[0082] S2. The reactant hydroquinone (0.90 mol) was divided into three equal parts and added to the reaction system in three batches. After the first batch of hydroquinone (0.30 mol) was added to the system, the temperature was raised to 200°C and the reaction was carried out for 1 hour; after the second batch of hydroquinone (0.30 mol) was added to the system, the temperature was raised to 230°C and the reaction was carried out for 1 hour; after the third batch of hydroquinone (0.30 mol) was added to the system, the temperature was raised to 280°C and the reaction was carried out for 2 hours to obtain a block copolymer.

[0083] S3. Add 4-fluorobenzophenone (0.02 mol) to cap the product at 280°C for 0.5 h before pouring it out. The crude product was crushed and washed with acetone and deionized water multiple times by reflux until impurities such as diphenyl sulfone and inorganic salts were completely removed. A powdered product was obtained. The product was then extruded, granulated, and injection molded, and its performance was evaluated.

[0084] In this embodiment, the molar ratio of the total molar number of bisphenol fluorene and aromatic diphenol to the dihalogenated benzophenone is 1:1; the molar ratio of aromatic diphenol to the bisphenol fluorene is 1:0.11;

[0085] The molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:1.05;

[0086] The molar ratio of sodium carbonate to potassium carbonate is 1:0.5;

[0087] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is 0.02:1.

[0088] Example 2

[0089] The reaction conditions and preparation method are the same as those in Example 1, except that in Example 2, the amount of bisphenol fluorene added is increased to 0.25 mol, and the single amount of hydroquinone added is reduced to 0.25 mol.

[0090] Example 3

[0091] The reaction conditions and preparation method are the same as those in Example 1, except that in Example 3, the amount of bisphenol fluorene added is increased to 0.40 mol, and the single amount of hydroquinone added is reduced to 0.20 mol.

[0092] Example 4

[0093] The reaction conditions and preparation method are the same as those in Example 1, except that in Example 4, all the alkali metal salts are replaced with sodium carbonate, i.e., 1.10 mol of sodium carbonate is added.

[0094] Example 5

[0095] The reaction conditions and preparation method are the same as those in Example 1, except that in Example 5, the alkali metal salt is replaced with 0.55 mol of sodium carbonate and 76.02 g of potassium carbonate. The experimental results are shown in Table 1.

[0096] Example 6

[0097] A preparation method of polyaryletherketone, the preparation method comprising:

[0098] S1. Evacuate a 2L three-necked flask equipped with a mechanical stirrer, thermometer, and water separator, then fill it with high-purity nitrogen (≥99.99%). Repeat the evacuation three or more times to fully replace the air atmosphere in the system with a nitrogen atmosphere, and continue to introduce a certain flow of nitrogen to maintain it. Add 500g of N,N-dimethylformamide, 2,4'-difluorobenzophenone (1.15mol), and bisphenol fluorene (0.30mol) to the three-necked flask. Heat to 150°C until they are completely melted, then add sodium carbonate (1mol) and potassium carbonate (0.3mol). React at 150°C for 2h to obtain an oligomer.

[0099] S2. The reactant resorcinol (0.70 mol) was divided into three parts and added to the reaction system in three batches. After the first batch of resorcinol (0.20 mol) was added to the system, the temperature was raised to 180°C and the reaction was carried out for 2 hours; after the second batch of resorcinol (0.30 mol) was added to the system, the temperature was raised to 260°C and the reaction was carried out for 0.5 hours; after the third batch of resorcinol (0.20 mol) was added to the system, the temperature was raised to 300°C and the reaction was carried out for 1 hour to obtain a block copolymer.

[0100] S3. Add 4-chlorobenzophenone (0.01 mol) at 300°C for 0.5 h and then pour off. Crush the crude product and wash it with acetone and deionized water repeatedly under reflux until the solvent, inorganic salts, and other impurities are completely removed to obtain a powdered product. The product is then extruded, granulated, and injection molded, and its performance is evaluated.

[0101] In this embodiment, the molar ratio of the total molar number of bisphenol fluorene and aromatic diphenol to the dihalogenated benzophenone is 1:1.15; the molar ratio of aromatic diphenol to the bisphenol fluorene is 1:0.43;

[0102] The molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:1.30;

[0103] The molar ratio of sodium carbonate to potassium carbonate is 1:0.3;

[0104] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is 0.01:1.

[0105] Example 7

[0106] A preparation method of polyaryletherketone, the preparation method comprising:

[0107] S1. Evacuate a 2L three-necked flask equipped with a mechanical stirrer, thermometer, and water separator, then fill it with high-purity nitrogen (≥99.99%). Repeat the evacuation three or more times to fully replace the air atmosphere in the system with a nitrogen atmosphere, and continue to introduce a certain flow of nitrogen to maintain the atmosphere. Add 500g of dimethyl sulfoxide, 4,4'-dichlorobenzophenone (0.95mol), and bisphenol fluorene (0.35mol) to the three-necked flask. Heat to 180°C until they are completely melted, then add sodium carbonate (0.9mol) and potassium carbonate (0.08mol), and react at 180°C for 0.5h to obtain an oligomer.

[0108] S2. The reactant bisphenol A (0.65 mol) was divided into three parts and added to the reaction system in three batches. After the first batch of bisphenol A (0.20 mol) was added to the system, the temperature was raised to 230°C and the reaction was carried out for 0.5 h; after the second batch of bisphenol A (0.25 mol) was added to the system, the temperature was raised to 270°C and the reaction was carried out for 1 h; after the third batch of bisphenol A (0.20 mol) was added to the system, the temperature was raised to 290°C and the reaction was carried out for 1.5 h to obtain a block copolymer.

[0109] S3. Add 4-fluorobiphenyl (0.05 mol) to cap the product at 300°C for 1 hour and then pour it out. Crush the crude product and wash it with acetone and deionized water repeatedly under reflux until the solvent, inorganic salts and other impurities are completely removed to obtain a powdered product. Then, perform extrusion, granulation, and injection molding, and evaluate its performance.

[0110] In this embodiment, the molar ratio of the total molar number of bisphenol fluorene and aromatic diphenol to the dihalogenated benzophenone is 1:0.95; the molar ratio of aromatic diphenol to the bisphenol fluorene is 1:0.54;

[0111] The molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:1.30;

[0112] The molar ratio of sodium carbonate to potassium carbonate is 1:0.09;

[0113] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is 0.05:1.

[0114] Comparative Example 1

[0115] The reaction conditions and preparation method are the same as those in Example 1, except that in this comparative example 1, all bisphenol fluorene is replaced by hydroquinone. The specific steps are as follows:

[0116] S1. Evacuate a 2L three-necked flask equipped with a mechanical stirrer, thermometer, and water separator, then fill it with high-purity nitrogen (≥99.99%). Repeat the evacuation three or more times to fully replace the air atmosphere in the system with a nitrogen atmosphere, and continue to introduce a certain flow of nitrogen to maintain it. Add 500g of diphenyl sulfone (2.29mol), 4,4'-difluorobenzophenone (1.00mol), and hydroquinone (0.10mol) to the three-necked flask. After heating to 160°C and completely melting, add sodium carbonate (0.70mol) and potassium carbonate (0.35mol), and react at 160°C for 1h to obtain an oligomer.

[0117] S2. The reactant hydroquinone (0.90 mol) was divided into three equal parts and added to the reaction system in three batches. After the first batch of hydroquinone (0.30 mol) was added to the system, the temperature was raised to 200°C and the reaction was carried out for 1 hour; after the second batch of hydroquinone (0.30 mol) was added to the system, the temperature was raised to 230°C and the reaction was carried out for 1 hour; after the third batch of hydroquinone (0.30 mol) was added to the system, the temperature was raised to 280°C and the reaction was carried out for 2 hours to obtain a block copolymer.

[0118] S3. Add 4-fluorobenzophenone (0.02 mol) to cap the product at 280°C for 0.5 h before pouring it out. The crude product was crushed and washed with acetone and deionized water multiple times by reflux until impurities such as diphenyl sulfone and inorganic salts were completely removed. A powdered product was obtained. The product was then extruded, granulated, and injection molded, and its performance was evaluated.

[0119] In this embodiment, the molar ratio of the total moles of aromatic diphenol to the dihalogenated benzophenone is 1:1;

[0120] The molar ratio of the total moles of aromatic diphenol to the alkali metal carbonate is 1:1.05;

[0121] The molar ratio of sodium carbonate to potassium carbonate is 1:0.5;

[0122] The ratio of the amount of the end-capping agent to the total molar number of the aromatic diphenol is 0.02:1.

[0123] Comparative Example 2

[0124] The reaction conditions and preparation method are the same as those in Example 1, except that: in this comparative example 2, all the hydroquinone added as feed is replaced with bisphenol fluorene and combined with the first feed, and 1.00 mol of bisphenol fluorene is added as feed in one go. The specific steps are as follows:

[0125] S1. Evacuate a 2L three-necked flask equipped with a mechanical stirrer, thermometer, and water separator, then fill it with high-purity nitrogen (≥99.99%). Repeat the evacuation three or more times to fully replace the air atmosphere in the system with a nitrogen atmosphere, and continue to introduce a certain flow of nitrogen to maintain it. Add 500g of diphenyl sulfone (2.29mol), 4,4'-difluorobenzophenone (1.00mol), and bisphenol fluorene (1.00mol) to the three-necked flask. Heat to 160℃ until they are completely melted, then add sodium carbonate (0.70mol) and potassium carbonate (0.35mol), and react at 160℃ for 5h.

[0126] S2. Add 4-fluorobenzophenone (0.02 mol) to cap the product at 280°C for 0.5 h before pouring it off. The crude product was crushed and washed with acetone and deionized water multiple times by reflux until impurities such as diphenyl sulfone and inorganic salts were completely removed. A powdered product was obtained. The product was then extruded, granulated, and injection molded, and its performance was evaluated.

[0127] In this embodiment, the molar ratio of the total moles of bisphenol fluorene to the dihalogenated benzophenone is 1:1; the molar ratio of the bisphenol fluorene is 1:0.11;

[0128] The molar ratio of the total moles of the bisphenol fluorene to the alkali metal carbonate is 1:1.05;

[0129] The molar ratio of sodium carbonate to potassium carbonate is 1:0.5;

[0130] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene is 0.02:1.

[0131] Comparative Example 3

[0132] The reaction conditions and preparation method are the same as those in Example 1, except that in step S2 of this comparative example 3, hydroquinone is fed in one go. The specific steps are as follows:

[0133] S1. Evacuate a 2L three-necked flask equipped with a mechanical stirrer, thermometer, and water separator, then fill it with high-purity nitrogen (≥99.99%). Repeat the evacuation three or more times to fully replace the air atmosphere in the system with a nitrogen atmosphere, and continue to introduce a certain flow of nitrogen to maintain it. Add 500g of diphenyl sulfone (2.29mol), 4,4'-difluorobenzophenone (1.00mol), and bisphenol fluorene (0.10mol) to the three-necked flask. Heat to 160°C until they are completely melted, then add sodium carbonate (0.70mol) and potassium carbonate (0.35mol), and react at 160°C for 1h to obtain an oligomer.

[0134] S2. Add the reactant hydroquinone (0.90 mol) to the reaction system, raise the temperature to 200°C, and react for 1 hour; then raise the temperature to 230°C, and react for 1 hour; finally raise the temperature to 280°C, and react for 2 hours to obtain a block copolymer.

[0135] S3. Add 4-fluorobenzophenone (0.02 mol) to cap the product at 280°C for 0.5 h before pouring it out. The crude product was crushed and washed with acetone and deionized water multiple times by reflux until impurities such as diphenyl sulfone and inorganic salts were completely removed. A powdered product was obtained. The product was then extruded, granulated, and injection molded, and its performance was evaluated.

[0136] In this embodiment, the molar ratio of the total molar number of bisphenol fluorene and aromatic diphenol to the dihalogenated benzophenone is 1:1; the molar ratio of aromatic diphenol to the bisphenol fluorene is 1:0.11;

[0137] The molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:1.05;

[0138] The molar ratio of sodium carbonate to potassium carbonate is 1:0.5;

[0139] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is 0.02:1.

[0140] Comparative Example 4

[0141] The reaction conditions and preparation method are the same as those in Example 1, except that in this comparative example 4, bisphenol fluorene and hydroquinone are added to the reaction system at the same time for reaction. The specific steps are as follows:

[0142] S1. Evacuate a 2L three-necked flask equipped with a mechanical stirrer, a thermometer, and a water separator, then fill it with high-purity nitrogen (≥99.99%). Repeat the evacuation three or more times to fully replace the air atmosphere in the system with a nitrogen atmosphere, and continuously introduce a certain flow of nitrogen to maintain it. Add 500g of diphenyl sulfone (2.29mol), 4,4'-difluorobenzophenone (1.00mol), bisphenol fluorene (0.10mol), and hydroquinone (0.90mol) to the three-necked flask, raise the temperature to 160°C, and after they are completely melted, add sodium carbonate (0.70mol) and potassium carbonate (0.35mol), and react at 160°C for 1h; then raise the temperature to 200°C, react for 1h; then raise the temperature to 230°C, react for 1h; finally, raise the temperature to 280°C, and react for 2h to obtain a block copolymer.

[0143] S2. Add 4-fluorobenzophenone (0.02 mol) to cap the product at 280°C for 0.5 h before pouring it off. The crude product was crushed and washed with acetone and deionized water multiple times by reflux until impurities such as diphenyl sulfone and inorganic salts were completely removed. A powdered product was obtained. The product was then extruded, granulated, and injection molded, and its performance was evaluated.

[0144] In this embodiment, the molar ratio of the total molar number of bisphenol fluorene and aromatic diphenol to the dihalogenated benzophenone is 1:1; the molar ratio of aromatic diphenol to the bisphenol fluorene is 1:0.11;

[0145] The molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:1.05;

[0146] The molar ratio of sodium carbonate to potassium carbonate is 1:0.5;

[0147] The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is 0.02:1.

[0148] The polyaryletherketones prepared in the above examples and comparative examples were subjected to performance tests, and the specific test results are shown in Table 1 below.

[0149] Table 1 Polyaryletherketone material performance test data

[0150]

[0151] As can be seen from Table 1 above, the poly(aryletherketone) materials prepared using the preparation method of the present invention in all examples and comparative examples exhibit higher thermal decomposition temperatures (all greater than 550°C), corrosion resistance, and mechanical properties. Furthermore, by adjusting the ratio of bisphenol fluorene introduced, the material can be endowed with ideal processing properties (melt flow index 8.0-30.0 g / 10 min). The preparation method of the present invention, by introducing bisphenol fluorene as a block comonomer in a conventional poly(aryletherketone) preparation method, produces a high-quality novel poly(aryletherketone) material. Furthermore, the preparation method of the present invention exhibits significant energy efficiency advantages over conventional poly(aryletherketone) materials, demonstrating its high value for industrial production and commercial application. Figure 2 The TGA curve of the polyaryletherketone obtained in Example 1 is shown in FIG. Figure 2 It can be seen that the polyaryletherketone product prepared by this method has extremely high thermal stability and can meet the requirements of use under a variety of harsh conditions.

[0152] By comparing the data of Examples 1, 4, and 5, it can be seen that: due to the large steric effect of bisphenol fluorene, the activity becomes poor, and the weaker alkalinity of sodium carbonate is insufficient for it to fully react with fluoroketone, thereby affecting the molecular weight of the product and ultimately affecting the overall performance of the product; by introducing an appropriate amount of highly active potassium carbonate for catalysis, the salt formation of bisphenol fluorene can be more complete and sufficient in the early prepolymerization stage, ensuring that a regular block main chain structure can be formed when hydroquinone is introduced, thereby ensuring the comprehensive performance of the product.

[0153] Comparison of the data from Examples 1 to 3 shows that as the amount of bisphenol fluorene increases, the tensile strength, modulus, and corrosion resistance of the product all improve to a certain extent, demonstrating the feasibility of introducing bisphenol fluorene as the second phenol for block copolymerization with fluoroketone as proposed in the present invention. Furthermore, a comparison of the measured melt index of the product with a currently available commercial standard product reveals that efficient injection molding of the material can be achieved by adjusting the amount of bisphenol fluorene introduced, the processing temperature (350-380°C), and the screw speed (60-80 rpm), demonstrating its potential for industrialization.

[0154] By comparing the data of Example 1 with that of Comparative Example 1, it can be seen that if the bisphenol fluorene monomer is not introduced, the corrosion resistance and mechanical properties of the obtained polyaryletherketone material will deteriorate, because the rigid chain structure of bisphenol fluorene can limit the thermal motion of the molecular chain, giving the product high strength and modulus; at the same time, the hydrophobic group of the fluorene ring can reduce the penetration of solvent molecules into the polymer chain, thereby significantly improving its stability in acids, alkalis and organic solvents. Figure 1 The tensile curves of the polyaryletherketone products of Example 1 and Comparative Example 1 are compared. Figure 1 It can be seen that the introduction of bisphenol fluorene will greatly improve the mechanical properties of the product, giving the material higher tensile strength and modulus, while the elongation at break will decrease. The mechanical properties of the final product can be adjusted by adjusting the proportion of bisphenol fluorene introduced according to product performance requirements.

[0155] By comparing the data of Example 1 and Comparative Example 2, it can be seen that if bisphenol fluorene is used entirely, although the mechanical properties, corrosion resistance and thermal stability of the product are significantly improved, this will also increase the viscosity of the product and make processing more difficult. Therefore, it is necessary to adjust the introduction ratio of bisphenol fluorene to retain some hydroquinone as a "soft segment" to ensure product performance and meet product performance requirements while maintaining a certain degree of processability.

[0156] By comparing the data of Example 1 with that of Comparative Example 3, it can be seen that adding hydroquinone in batches can effectively alleviate problems such as insufficient reaction caused by different monomer reactivity, making the arrangement of the two structural units in the main chain structure more regular, thereby forming a complete block polymer network, and giving the material higher mechanical properties and chemical corrosion resistance.

[0157] By comparing the data of Example 1 and Comparative Example 4, it can be seen that due to the influence of the large steric hindrance group, the reactivity of hydroquinone is much higher than that of bisphenol fluorene. If both are added at the same time in the early stage of the reaction, it will make it difficult for bisphenol fluorene to fully react and block into the main chain structure, ultimately resulting in the deterioration of the overall performance of the product and failure to achieve the expected effect.

[0158] The technical features of the above-described embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above-described embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0159] For those skilled in the art, several variations and improvements may be made without departing from the scope of the present invention, which all fall within the scope of protection of the present invention. The scope of protection of the present invention shall be based on the appended claims.

Claims

1. A method for preparing polyaryletherketone, characterized in that: The preparation method is: S1. Under inert gas conditions, dihalogenated benzophenone and bisphenol fluorene are added to a solvent and mixed evenly, and an alkali metal carbonate is added and reacted under heating conditions to obtain an oligomer; S2, adding aromatic diphenols to the system of step S1 in batches, and performing a temperature-programmed reaction to obtain a block copolymer; S3, adding a capping agent to the system to carry out a capping reaction, and after the reaction is completed, post-processing to obtain polyaryletherketone; In step S1, the reaction temperature is 150-180°C and the reaction time is 0.5-2h; In step S2, the aromatic diphenol is added to the reaction system in three batches. After the first batch of aromatic diphenol is added to the system, the temperature is raised to 180~230°C and the reaction is carried out for 0.5~2h; after the second batch of aromatic diphenol is added to the system, the temperature is raised to 230~270°C and the reaction is carried out for 0.5~2h; after the third batch of aromatic diphenol is added to the system, the temperature is raised to 270~300°C and the reaction is carried out for 0.5~2h.

2. The method for preparing polyaryletherketone according to claim 1, wherein: The dihalogenated benzophenone is at least one of 2,4'-difluorobenzophenone, 4,4'-difluorobenzophenone, 4,4'-dichlorobenzophenone, and 4,4'-dibromobenzophenone; The aromatic diphenol is at least one of hydroquinone, resorcinol, biphenol, bisphenol A and phenolphthalein.

3. The method for preparing polyaryletherketone according to claim 1, wherein: The molar ratio of the total molar number of the bisphenol fluorene and the aromatic diphenol to the dihalogenated dibenzophenone is 1:(0.95-1.15); the molar ratio of the aromatic diphenol to the bisphenol fluorene is 1:(0.1-0.8).

4. The method for preparing polyaryletherketone according to claim 1, wherein: The molar ratio of the total moles of the bisphenol fluorene and the aromatic diphenol to the alkali metal carbonate is 1:(0.98-1.30); The alkali metal carbonate is at least one of potassium carbonate, sodium carbonate and cesium carbonate.

5. The method for preparing polyaryletherketone according to claim 4, wherein: The alkali metal carbonate is a combination of sodium carbonate and potassium carbonate, and the molar ratio of the sodium carbonate to the potassium carbonate is 1: (0.01-0.5).

6. The method for preparing polyaryletherketone according to claim 1, characterized in that: The solvent is any one of sulfolane, N,N-dimethylformamide, N,N-dimethylacetamide, diphenyl sulfone, dimethyl sulfoxide, and N-methylpyrrolidone.

7. The method for preparing polyaryletherketone according to claim 1, characterized in that: The end-capping agent is at least one of 4-fluorobenzophenone, 4-chlorobenzophenone, and 4-fluorobiphenyl; The ratio of the amount of the end-capping agent to the total molar number of the bisphenol fluorene and the aromatic diphenol is (0.01-0.05):

1.

8. The method for preparing polyaryletherketone according to claim 1, characterized in that: In step S3, the post-treatment operation method is: after the reaction is completed, the product is poured into cold water to cool and solidify, the solid is taken and crushed, washed and dried to obtain the polyaryletherketone product.

Images