Polyaryl ketone based on Claisen polycondensation and preparation and application of functional derivative of polyaryl ketone

Abstract

The invention relates to preparation and application of polyaryl ketone based on Claisen polycondensation and a functional derivative of the polyaryl ketone. The claisen polycondensation reaction is creatively applied to the synthesis of the polyaryl ketone material. Through precise design of reaction substrates, controllable construction of polymers with different microstructures is realized, and various polymers with clear structures such as linear polyaryl ether ketone, star-shaped polyaryl ketone and fluorescent polyaryl ketone are successfully prepared. Furthermore, through post-modification reactions such as Bayer-Villiger oxidation and ketoamine condensation, the polyaryletherketone is efficiently converted into a series of functional materials such as polyaryletherketone ester, polyaryletherketone imine and polyaryletherketoxime, and the diversity and functionality of the material structure are expanded. Besides, through the hydrolysis reaction of the polyaryl ether ketone ester, the efficient recovery of the micromolecular benzoic acid compound is realized, and the potential of the strategy in the aspects of cyclic utilization and sustainability is embodied. According to the polymerization method based on Claisen condensation, a new way which is mild in condition, simple and convenient to operate and flexible in structure regulation and control is provided for synthesis of a functional degradable polyketone material.

Description

Preparation and application of polyaryl ketones and their functionalized derivatives based on Claysen polycondensation Technical Field

[0001] This invention belongs to the field of polymer synthetic chemistry and biodegradable engineering plastics, specifically relating to a method for preparing polyaryl ketones based on Claisen polycondensation reaction, and the application of polyaryl ketones and their derivatives obtained by this method in biodegradable high-performance materials. Background Technology

[0002] With technological advancements and rising human demands for a high quality of life, the application of polymer materials is increasingly in demand. Driven by economic growth and population expansion, global plastic consumption is projected to nearly triple by 2060. However, plastic waste will also triple at the same time. Half of this plastic waste still ends up in landfills, less than one-fifth is recycled, and a significant portion is released into the environment uncontrolled. Therefore, plastic pollution is one of the biggest environmental challenges of the 21st century, causing widespread damage to ecosystems and human health, while the fossil fuel sources of most plastics have a significant impact on climate change. The preparation of degradable and reusable plastics is crucial for mitigating the impacts of plastic waste production, degradation, and recycling. Embedding degradable functional groups into polymer chains is one strategy for preparing degradable polymer materials.

[0003] Polyketone materials have attracted widespread attention due to their enhanced thermal properties and inherent degradability via the Norrish pyrolysis reaction. Secondly, since 2004, the Kyoko Nozaki group has explored the partial Bayer-Villager oxidation of completely alternating optically active polyacrylamide (PAPE) using m-chloroperoxybenzoic acid (m-CPBA) to generate random polyketone / ester compounds, with 12% of the ketones converted to esters. The resulting polyketone esters have biodegradability potential (Figure 1a). In 2024, the group used the milder hydrogen peroxide as an oxidant to achieve a 35% conversion of ketones to ester groups in PAPE. Furthermore, polyketone materials have many potential functional transformations, such as the reaction of polyketones with hydroxylamine or ammonia to convert them into polyamides (Figure 1b); the controllable reduction of ketones to alcohols using sodium borohydride, followed by acetylation with various alkyl chlorides; and the reaction of polyketones with hydroxylamine to generate polyoximes, etc. (Figure 1c).

[0004] Polyketone materials can be classified into aliphatic and aromatic polyketones. Currently, aliphatic polyketones are generally prepared by copolymerization of ethylene or propylene with carbon monoxide catalyzed by a transition metal catalyst (Figure 2a). In 2021, Stefan Mecking's group discovered that a nickel catalyst coordinated with phosphonic acid can catalyze the non-crosslinking copolymerization of ethylene and carbon monoxide, adding low-density single-chain ketone groups to the high-molecular-weight polyethylene chain while maintaining ideal material properties. After conventional injection molding, the tensile properties remain comparable to standard high-density polyethylene, and it also exhibits photodegradability. In 2024, Professor Liu Ye's group achieved ternary copolymerization of ethylene, propylene, and carbon monoxide using a nickel phosphonate catalyst. The designed catalyst can catalyze the on-demand conversion of ethylene and carbon monoxide gas into polyketone, with quantitative yield and product specificity. The preparation of polyketone materials using transition metal-catalyzed coordination polymerization methods often requires highly efficient catalysts and high-pressure carbon monoxide gas, resulting in high costs and low safety. However, polyaryl ketones are a class of semi-crystalline thermoplastics with highly aromatic and linear molecular skeletons, possessing excellent mechanical and physicochemical properties. These materials are considered to have the highest performance among all thermoplastics; therefore, polyaryl ketones are often used in demanding applications such as aerospace, oil and gas drilling, and high-tech fields like biomedicine. Currently, the synthetic routes for polyaryl ketones are generally of two types: one is the nucleophilic substitution of difluorinated compounds with bisphenol compounds, but this method often requires high-temperature conditions (190~320℃) for polymerization. o C) (Figure 2b); another type is the electrophilic arylation reaction of diaryl chlorides with diaryl ethers (Figure 2c). Both of these synthetic methods have limitations such as demanding reaction conditions or a limited range of applicable functional monomers. It is worth noting that recently, polyaryl ketone materials have been considered for use in nuclear power plant containment structures, battery separators, and cryogenic hydrogen storage devices; therefore, developing novel methods for preparing polyaryl ketones is of great significance.

[0005] Claisen condensation is a common reaction type in organic chemistry. It involves the condensation of esters containing α-active hydrogen in the presence of a base, resulting in the loss of one molecule of alcohol to yield a β-keto ester. Through clever design of the reactants, a series of polyaryl ketone materials can be prepared using this reaction under mild conditions. In summary, this invention aims to apply Claisen condensation to the preparation of polyaryl ketones (Figure 2d); various aryl diketones and aryl diesters containing α-active hydrogen were designed to prepare a series of polyaryl ketone materials with different chain structures; and the degradation performance and functional group transformation properties of the prepared materials were preliminarily investigated. Summary of the Invention

[0006] This invention aims to overcome the problems of harsh reaction conditions, limited substrate applicability, difficulty in precisely controlling molecular structure, and difficulty in achieving material degradation and functionalization in existing polyaryl ketone synthesis methods. It provides a method for preparing polyaryl ketones based on Claisen polycondensation. This method, through systematic design of the monomer structure and reaction conditions, achieves efficient synthesis of polyaryl ketones under relatively mild conditions, and further expands its applications in functional modification, biodegradable materials, and recycling.

[0007] Specifically, existing polyaryl ketone materials are typically prepared using high-temperature nucleophilic substitution reactions or electrophilic aromatic substitution reactions under strong Lewis acid conditions. These methods are not only demanding and energy-intensive, but also exhibit poor compatibility with monomer functional groups, making it difficult to construct diverse and functionalizable polyaryl ketone materials. Therefore, there is an urgent need to develop a novel polyaryl ketone synthesis strategy that offers mild reaction conditions, flexible structural control, and a wide range of applicable substrates.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] First aspect: Preparation method of polyaryl ketones

[0010] This invention provides a method for preparing polyaryl ketones based on Claisen polycondensation reaction, the method comprising the following steps:

[0011] Under inert gas protection, aryl diketone compounds containing α-active hydrogen are mixed with aryl or cycloalkyl diester compounds in an organic solvent, and Claisen polycondensation reaction is carried out under the action of organometallic strong base. After the reaction is completed, polyaryl ketone materials containing aromatic ketone structural units in the main chain are obtained through precipitation, separation, washing and drying steps.

[0012] In this invention, the aryl diketone is an aromatic compound containing two or more ketone groups in its molecule, and at least one ketone group has an active hydrogen at its α-position. By designing the structure of the aryl diketone, polyaryl ketones with different topologies can be constructed.

[0013] Preferably, the aryl diketone is selected from at least one of the following:

[0014] (1) Linear aryl ether ketone compounds;

[0015] (2) Aryl diketone compounds containing flexible alkyl or ether chains;

[0016] (3) Star-shaped aryl polyketone compounds with three or more arms;

[0017] (4) Aryl diketone compounds with para or meta substitution of the aromatic ring.

[0018] In this invention, the type of aryl or cycloalkyl diester compound is not particularly limited, as long as it can participate in the Claisen polycondensation reaction under alkaline conditions. Preferably, the diester compound is selected from at least one of diester, isophthalate, its structural isomers, and cyclohexanedicarboxylate.

[0019] In this invention, the molar ratio of the aryl diketone compound to the aryl or cycloalkyl diester compound is 1:(0.5-1.5).

[0020] In this invention, the type of organometallic strong base is not particularly limited, as long as it can initiate the deprotonation of the aryl diketone and promote the Claisen condensation reaction. Preferably, the organometallic strong base is selected from alkali metal or alkaline earth metal alkoxides, hydrides, or mixtures thereof, more preferably from at least one of potassium tert-butoxide, sodium tert-butoxide, potassium methoxide, and sodium methoxide. The amount of the organometallic strong base used is 1.5-5 times the molar amount of the aryl diketone compound.

[0021] In this invention, the organic solvent is preferably a polar amide solvent to facilitate the dissolution of the reactants and the polycondensation reaction. Preferably, the solvent is selected from at least one of N,N-dimethylformamide, N-methylpyrrolidone, and dimethylimidazolinone. The volume of the polar amide solvent is 3-10 mL / 6 mmol of raw material.

[0022] In this invention, the reaction temperature of the Claisen polycondensation reaction is 20-180°C. o C, preferably 40-60 o C; The reaction time is 2-72 hours, preferably 8-24 hours. By controlling the reaction conditions, polyaryl ketone materials with different molecular weights and molecular weight distributions can be obtained.

[0023] Second aspect: Structural regulation of polyaryl ketones

[0024] By designing the structure of aryl diketone monomers and adjusting the reaction conditions, a variety of polyaryl ketone materials with different microstructures were constructed.

[0025] In some preferred embodiments, linear polyaryl ketone materials can be prepared by using linear aryl diketone monomers; star-shaped or multi-arm polyaryl ketone materials can be prepared by using multifunctional aryl polyketone monomers; and polyaryl ketone materials with fluorescent properties can be prepared by introducing aromatic units with luminescent properties.

[0026] The third aspect: Post-modification and functionalization of polyaryl ketones

[0027] The present invention also provides a method for post-modifying the polyaryl ketone obtained by the above method.

[0028] In some embodiments, the polyaryl ketone can undergo a Baeyer-Villiger oxidation reaction under the action of a peroxidant, converting some of the main chain ketone groups into ester groups, thereby obtaining a polyaryl ketone ester material containing an ester bond structure, thus endowing the material with potential degradability.

[0029] In other embodiments, the polyaryl ketone can undergo ketamine condensation or oxime reaction with diamine, hydroxylamine or their derivatives to prepare polyaryl ketone imine or polyaryl ketone oxime materials, thereby further expanding their chemical functionality and application range.

[0030] Fourth aspect: Applications of polyaryl ketones and their derivatives

[0031] This invention also provides the application of polyaryl ketones and their functionalized derivatives prepared by the above method in biodegradable thermoplastic materials, engineering plastics, membrane materials, radiation-resistant materials, and recyclable chemical recycling systems.

[0032] In some preferred embodiments, small molecule aromatic acid compounds can be recovered by hydrolyzing polyaryl ketone ester materials, demonstrating the potential value of this material system in terms of recycling and sustainable development.

[0033] Through the above technical solutions, the present invention has the following advantages and beneficial effects:

[0034] (1) This invention is the first to systematically apply the Claysen polycondensation reaction to the preparation of polyaryl ketones, with mild reaction conditions and significantly reduced energy consumption;

[0035] (2) The method of the present invention has a wide range of substrates and can achieve the controllable construction of the microstructure of polyaryletones through monomer structure design;

[0036] (3) The polyaryl ketone backbone obtained is rich in ketone groups, which makes it easy to carry out a variety of post-modification reactions and has strong functional expansion capabilities;

[0037] (4) Baeyer–Villiger oxidation can introduce ester bonds into the polymer backbone, giving the material potential degradability;

[0038] (5) The method of this invention is simple in process, controllable in operation, and has good scale-up potential and industrial application prospects. (See attached figures)

[0039] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0040] Figure 1. Multiple functional transformations of polyketone.

[0041] Figure 2. Synthesis of polyketone.

[0042] Figure 3. Infrared spectra of polyaryletherketone before and after oxidation.

[0043] Figure 4. Hydrogen spectrum of polyaryletherketone ester after hydrolysis.

[0044] Figure 5. Carbon spectrum of polyaryletherketone ester after hydrolysis.

[0045] Figure 6. Infrared spectra of polyaryletherketone functional groups before and after transformation. Detailed Implementation

[0046] The present invention will be further described in detail below with reference to specific embodiments. Those skilled in the art should understand that the present invention is not limited to the following embodiments, and any equivalent substitutions or modifications made to the present invention without departing from its spirit and essence should fall within the protection scope of the present invention.

[0047] In this invention, unless otherwise stated, all percentages are mass percentages, and all temperatures are Celsius temperatures. o C), the room temperature refers to 20-25°C. o C.

[0048] The numerical ranges and their endpoints listed in this document, as well as any specific values, should not be construed as absolutely precise boundaries, but rather as reasonable ranges or variations that include the stated values ​​or adjacent ranges. Reasonable deviations or errors that may exist in measurement, calculation, or implementation should be considered when interpreting these values. All disclosed numerical range endpoints, endpoints and specific values, and different specific values ​​can be combined or interleaved to form new numerical ranges or sets of values ​​with clear technical meaning. These numerical ranges derived through reasonable combinations should also be considered as explicitly disclosed and supported in this document.

[0049] In specific embodiments of the present invention, the aryl diketone monomers, aryl or cycloalkyl diester monomers used can be prepared or purchased by conventional methods in the art, and no special treatment is required before use, unless otherwise stated.

[0050] In this invention, the aryl diketone monomer is an aromatic compound containing two or more ketone groups in its molecule, and at least one ketone group has an active hydrogen at its α-position. The aryl diketone monomer can be a linear structure, a star structure with three or more arms, or a modified structure with the introduction of ether chains, flexible segments, or luminescent groups.

[0051] In this invention, the type of aryl or cycloalkyl diester monomer is not particularly limited, as long as it can undergo Claisen polycondensation with the aryl diketone monomer under alkaline conditions. Preferably, the diester monomer includes, but is not limited to, dimethyl terephthalate, diethyl terephthalate, dimethyl isophthalate, diethyl isophthalate, their structural isomers, and cyclohexanedicarboxylate.

[0052] In this invention, the organometallic strong base used is selected from alkali metal or alkaline earth metal alkali salts, hydrides, or mixtures thereof. Preferably, the organometallic strong base includes at least one selected from potassium tert-butoxide, sodium tert-butoxide, potassium methoxide, and sodium methoxide.

[0053] In this invention, the reaction solvent is preferably a polar amide solvent, including but not limited to N,N-dimethylformamide (DMF), N-methylpyrrolidone (NMP), and dimethylimidazolinone (DMI). These solvents can effectively dissolve the reactants and promote the Claisen polycondensation reaction. The volume of the polar amide solvent is 3–10 mL / 6 mmol of raw material.

[0054] In this invention, the structure of the obtained polyaryl ketones and their derivatives was characterized using Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance spectroscopy (NMR). 1 H NMR, 13 The characterization was confirmed by methods such as C NMR; the molecular weight and molecular weight distribution were determined by gel permeation chromatography (GPC). Unless otherwise specified, all characterization methods described are conventional techniques in the art.

[0055] In a general embodiment of the present invention, the method for preparing polyaryl ketones based on Claisen polycondensation reaction includes the following steps:

[0056] Under inert gas protection, aryl diketone monomers and aryl or cycloalkyl diester monomers are added to a reaction vessel in a predetermined molar ratio, and an appropriate amount of polar amide solvent is added to fully dissolve or disperse the reactants and form a homogeneous reaction system.

[0057] Subsequently, under stirring conditions, a strong organometallic base is added to the above reaction system to initiate the deprotonation reaction of the active hydrogen at the α-position in the aryl diketone monomer, causing it to undergo Claisen condensation reaction with the diester monomer, thereby gradually forming a polyaryl ketone containing aromatic ketone structural units in the main chain.

[0058] In this invention, the molar ratio of the aryl diketone monomer to the aryl or cycloalkyl diester monomer can be adjusted within a wide range. Preferably, the molar ratio of the aryl diketone to the diester is 1:(0.5-1.5), more preferably 1:(0.8-1.2).

[0059] In this invention, the amount of the organometallic strong base is based on the molar amount of the aryl diketone monomer, preferably 1.5-5 times the molar amount, more preferably 2-3 times the molar amount.

[0060] In this invention, the reaction temperature of the Claisen polycondensation reaction is 20-180°C. o C, preferably 40-60 o C; The reaction time is 2-72 hours, preferably 8-24 hours. By adjusting the reaction temperature, time, and reactant concentration, the molecular weight and molecular weight distribution of the polymer can be controlled.

[0061] After the reaction was complete, the reaction solution was slowly poured into an acidified aqueous solution to precipitate the polymer. After centrifugation or filtration, the obtained solid was washed successively with deionized water and lower alcohol to remove residual solvent and inorganic salts, and then dried under vacuum to obtain the target polyaryl ketone material.

[0062] The following examples further illustrate the technical solution of the present invention by changing the structure of the aryl diketone monomer, the type of diester monomer, the reaction conditions, and the subsequent treatment methods, based on the general preparation method described above.

[0063] Unless otherwise specified, each embodiment changes only one or a few experimental variables while keeping the other conditions consistent, in order to highlight the influence of different parameters on the Claisen polycondensation reaction and the structure and properties of polyaryl ketones.

[0064] In this invention, the preparation methods of some aryl diketone compounds are as follows:

[0065] Example 1

[0066]

[0067] This embodiment provides a method for synthesizing an aryl diketone compound of formula (I-1), comprising the following steps:

[0068] Acetyl chloride (1.88 g, 24 mmol), aluminum trichloride (2.39 g, 18 mmol), and anhydrous dichloroethane (10 mL) were sequentially added to a 100 mL round-bottom flask. At room temperature, a mixture of diphenylmethyl (1.01 g, 6 mmol) and anhydrous dichloroethane (5 mL) was slowly added dropwise to the reaction mixture. After the addition was complete, the reaction mixture was heated to 40 °C. oThe mixture was stirred at C for 7 hours, and then the reaction mixture was poured into 50 mL of ice-cold concentrated hydrochloric acid. The organic layer was washed three times with water (50 mL × 3), three times with brine (50 mL × 3), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was separated by column chromatography (petroleum ether / ethyl acetate = 9 / 1) to give a white solid, which was the target compound (1.40 g, 93%). 1 H NMR (600 MHz, CDCl3): δ 7.90 (d, J = 8.3 Hz, 4H, Ar-H), 7.27 (d, J = 8.4 Hz, 4H, Ar-H), 4.09 (s, 2H, CH2), 2.58 (s, 6H, CH3) ppm.

[0069] Example 2

[0070]

[0071] This embodiment provides a method for synthesizing an aryl diketone compound of formula (I-2), comprising the following steps:

[0072] Following the synthetic steps of compound formula (I-1) in Experimental Example 1, diphenylmethyl was replaced with diphenyl ether (1.02 g, 6 mmol) in the reaction. The crude product was recrystallized from dichloromethane / petroleum ether to obtain white crystals, which were the target compound (1.37 g, 90%). 1 H NMR (600 MHz, CDCl3): δ 7.99 (d, J = 8.4 Hz, 4H, Ar-H), 7.09 (d, J =8.5 Hz, 4H, Ar-H), 2.60 (s, 6H, CH3) ppm.

[0073] Example 3

[0074]

[0075] This embodiment provides a method for synthesizing aryl diketone compounds (I-3), including the following steps:

[0076] p-Hydroxyacetophenone (1.63 g, 12 mmol), 1,6-dibromohexane (1.22 g, 5 mmol), anhydrous potassium carbonate (1.66 g, 12 mmol), and N,N-dimethylformamide (20 mL) were added sequentially to a 100 mL round-bottom flask. The reaction mixture was heated to 50 °C. oThe reaction was carried out at C for 19 hours. After the reaction was completed, a small amount of hydrochloric acid was added to the reaction system to remove excess base. The organic phase was extracted with ethyl acetate, washed with water (50 mL × 3) to remove N,N-dimethylformamide, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The crude product was recrystallized from dichloromethane / petroleum ether to give white crystals, which were the target compound (1.63 g, 92%). 1 H NMR (600 MHz, CDCl3): δ 7.92 (d, J = 8.5 Hz, 4H, Ar-H), 6.92 (d, J =8.4 Hz, 4H, Ar-H), 4.04 (t, J = 6.4 Hz, 4H, OCH2), 2.55 (s, 6H, CH3), 1.87 -1.83 (m, 4H, OCH2CH2), 1.58 - 1.55 (m, 4H, OCH2CH2CH2) ppm.

[0077] Example 4

[0078]

[0079] This embodiment provides a method for synthesizing aryl diketone compounds of formula (I-4), including the following steps:

[0080] Following the synthetic procedure of compound formula (I-3) in Experimental Example 3, 1,6-dibromohexane was replaced with 1,10-dibromodecane (1.50 g, 5 mmol) in the reaction. The crude product was recrystallized from dichloromethane / petroleum ether to obtain white crystals, which were the target compound (1.94 g, 95%). 1 H NMR (600 MHz, CDCl3): δ 7.92 (d, J = 8.4 Hz, 4H, Ar-H), 6.92 (d, J = 8.5 Hz, 4H, Ar-H), 4.02 (t, J = 6.5 Hz, 4H, OCH2), 2.55 (s, 6H, CH3), 1.83 - 1.78 (m, 4H, OCH2CH2), 1.49 - 1.44 (m, 4H, OCH2CH2CH2), 1.38 - 1.34 (m,8H, OCH2CH2CH2CH2CH2) ppm.

[0081] Example 5

[0082]

[0083] This embodiment provides a method for synthesizing aryl diketone compounds of formula (I-5), including the following steps:

[0084] Following the synthetic procedure of compound formula (I-3) in Experimental Example 3, 1,6-dibromohexane was replaced with bis(2-bromoethyl) ether (1.16 g, 5 mmol) in the reaction. The crude product was recrystallized from dichloromethane / petroleum ether to obtain white crystals, which were the target compound (1.59 g, 93%). 1 H NMR (600 MHz, CDCl3): δ 7.92 (d, J = 8.4 Hz, 4H, Ar-H), 6.95 (d, J = 8.5 Hz, 4H, Ar-H), 4.22 (t, J = 4.7 Hz, 4H, OCH2), 3.96 (t, J = 4.7Hz, 4H, OCH2), 2.55 (s, 6H, CH3) ppm.

[0085] Example 6

[0086]

[0087] This embodiment provides a method for synthesizing aryl diketone compounds of formula (I-7), including the following steps:

[0088] Following the synthetic steps of compound formula (I-1) in Example 1, the diphenylmethyl group was replaced with triphenylmethyl (0.98 g, 4 mmol) in the reaction. The crude product was separated by column chromatography (petroleum ether / ethyl acetate = 9 / 1) to obtain a white solid, which was the target compound (1.37 g, 93%). 1 H NMR (600 MHz, CDCl3): δ 7.91 (d, J = 8.3 Hz, 6H, Ar-H), 7.20 (d, J = 8.1 Hz, 6H, Ar-H), 5.70 (s, 1H, CH), 2.59 (s, 9H, CH3) ppm.

[0089] Example 7

[0090]

[0091] This embodiment provides a method for synthesizing aryl diketone compounds of formula (I-8), including the following steps:

[0092] Following the synthetic steps of compound formula (I-1) in Example 1, the diphenylmethyl group was replaced with triphenylamine (0.98 g, 4 mmol) in the reaction. The crude product was separated by column chromatography (petroleum ether / ethyl acetate = 9 / 1) to obtain a green solid, which was the target compound (1.32 g, 89%). 1 H NMR (600 MHz, CDCl3): δ 7.91 (d, J = 8.2 Hz, 6H, Ar-H), 7.16 (d, J = 8.7 Hz, 6H, Ar-H), 2.59 (s, 9H, CH3) ppm.

[0093] Example 8

[0094]

[0095] This embodiment provides a method for synthesizing aryl diketone compounds of formula (I-9), including the following steps:

[0096] Following the synthetic steps of compound formula (I-1) in Example 1, diphenylmethyl was replaced with tetraphenylmethyl (0.64 g, 2 mmol) in the reaction. The crude product was separated by column chromatography (petroleum ether / ethyl acetate / dichloromethane = 9 / 1 / 1) to obtain a white solid, which was the target compound (0.85 g, 87%). 1 H NMR (600 MHz, CDCl3): δ 7.87 (d, J = 8.2 Hz, 8H, Ar-H), 7.34 (d, J = 8.2 Hz, 8H, Ar-H), 2.58 (s, 12H, CH3) ppm.

[0097] Examples 1-8 illustrate the preparation of some aryl diketone compounds.

[0098] The preparation route of polyaryl ketones in this invention is as follows:

[0099]

[0100] Example 9

[0101] Under inert gas protection, a Shrek reaction flask that has been anhydrous and has undergone three vacuuming and three argon purging operations to fully remove air from the flask was used. In a continuous argon atmosphere, aryl diketone compounds (Formula I-1, 3 mmol), diethyl isophthalate (Formula II-1, 3 mmol), potassium tert-butoxide (9 mmol), and strictly dehydrated N,N-dimethylformamide (DMF, 15 mL) were added to the reaction flask in sequence to form a homogeneous reaction system.

[0102] After the feed is completed, the reaction system is placed at a constant temperature of 25 ℃ and reacted for 16 hours under continuous stirring to allow the aryl diketone and diester monomer to undergo Claisen polycondensation under alkaline conditions.

[0103] After the reaction was complete, a suitable amount of deionized water was slowly added to the reaction system, and concentrated hydrochloric acid was added dropwise to quench the reaction while adjusting the pH of the system. Subsequently, the reaction mixture was extracted multiple times with ethyl acetate, the organic phases were combined, and the mixture was repeatedly washed with deionized water until the organic phase was clean.

[0104] The washed organic phase was subjected to vacuum distillation to remove ethyl acetate and other volatile organic solvents, yielding a crude product. Further, the crude product was washed with dichloromethane to remove any remaining unreacted monomers, small molecule byproducts, and oligomers. Finally, the resulting solid was dried to constant weight under vacuum to obtain the target polyaryl ketone material in 74% yield.

[0105] Gel permeation chromatography (GPC) analysis showed that the number-average molecular weight of the obtained polyaryl ketone was approximately 2.25 kDa, the weight-average molecular weight was approximately 2.60 kDa, and the molecular weight distribution was 1.16, indicating that the Claysen polycondensation reaction can effectively construct polyaryl ketone materials under mild conditions. Specific experimental results are shown in Table 1.

[0106] Example 10

[0107] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with sodium tert-butoxide (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0108] Example 11

[0109] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with lithium tert-butoxide (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0110] Example 12

[0111] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with sodium ethoxide (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0112] Example 13

[0113] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with potassium tert-butoxide (9 mmol) using potassium methoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0114] Example 14

[0115] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with sodium methoxide (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0116] Example 15

[0117] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with lithium methoxide (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0118] Example 16

[0119] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with lithium ethoxide (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0120] Example 17

[0121] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with potassium ethoxide (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0122] Example 18

[0123] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with sodium hydride (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0124] Example 19

[0125] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with potassium hexamethyldisilazane (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0126] Example 20

[0127] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with sodium hexamethyldisilazane (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0128] Example 21

[0129] The procedure was performed according to the method described in Example 9, except that the strong organometallic base was replaced with lithium diisopropylamine (9 mmol) instead of potassium tert-butoxide. All other reaction conditions remained the same as in Example 9. After the reaction was completed and subjected to the same post-treatment steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 1.

[0130] Table 1

[0131]

[0132] Examples 9-21 are screening for the bases used in the polymerization reaction, among which potassium tert-butoxide is the best.

[0133] Example 22

[0134] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 0°C. o C. The types and amounts of other reactants, the types and volumes of solvents, the organometallic strong bases used, the reaction time (16 h), and the post-treatment steps were all the same as in Example 9. After the reaction was completed, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. The specific experimental results are shown in Table 2.

[0135] Example 23

[0136] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 15°C. o C. The types and amounts of other reactants, the types and volumes of solvents, the organometallic strong bases used, the reaction time (16 h), and the post-treatment steps were all the same as in Example 9. After the reaction was completed, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. The specific experimental results are shown in Table 2.

[0137] Example 24

[0138] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 50°C. o C. The types and amounts of other reactants, the types and volumes of solvents, the organometallic strong bases used, the reaction time (16 h), and the post-treatment steps were all the same as in Example 9. After the reaction was completed, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. The specific experimental results are shown in Table 2.

[0139] Example 25

[0140] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 70°C. o C. The types and amounts of other reactants, the types and volumes of solvents, the organometallic strong bases used, the reaction time (16 h), and the post-treatment steps were all the same as in Example 9. After the reaction was completed, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. The specific experimental results are shown in Table 2.

[0141] Example 26

[0142] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 90°C. o C. The types and amounts of other reactants, the types and volumes of solvents, the organometallic strong bases used, the reaction time (16 h), and the post-treatment steps were all the same as in Example 9. After the reaction was completed, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. The specific experimental results are shown in Table 2.

[0143] Example 27

[0144] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 120°C. o C. The types and amounts of other reactants, the types and volumes of solvents, the organometallic strong bases used, the reaction time (16 h), and the post-treatment steps were all the same as in Example 9. After the reaction was completed, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. The specific experimental results are shown in Table 2.

[0145] Example 28

[0146] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 150°C. oC. The types and amounts of other reactants, the types and volumes of solvents, the organometallic strong bases used, the reaction time (16 h), and the post-treatment steps were all the same as in Example 9. After the reaction was completed, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. The specific experimental results are shown in Table 2.

[0147] Table 2

[0148]

[0149] Examples 22-28 are for screening the polymerization reaction temperature, among which 50 °C is the optimal temperature.

[0150] Example 29

[0151] The procedure was performed according to the method described in Example 9, except that the reaction temperature of the Claisen polycondensation reaction was controlled at 50°C. o C, and the reaction time was set to 2 h. The types and amounts of other reactants, the type and volume of solvent, the organometallic strong base used, and the post-treatment steps were all the same as in Example 9. After the reaction, the product was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone product. Specific experimental results are shown in Table 3.

[0152] Example 30

[0153] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 4 hours, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0154] Example 31

[0155] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 8 hours, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0156] Example 32

[0157] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 12 hours, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0158] Example 33

[0159] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 16 h, while all other reaction conditions remained the same. After the reaction was completed and subjected to the same post-processing steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 3.

[0160] Example 34

[0161] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 20 h, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0162] Example 35

[0163] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 24 hours, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 3.

[0164] Example 36

[0165] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 28 hours, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0166] Example 37

[0167] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 32 h, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0168] Example 38

[0169] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 36 h, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 3.

[0170] Example 39

[0171] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 40 h, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0172] Example 40

[0173] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 44 h, while all other reaction conditions remained the same. After the reaction was completed and subjected to the same post-processing steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 3.

[0174] Example 41

[0175] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 48 h, while all other reaction conditions remained the same. After the reaction was completed and subjected to the same post-processing steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 3.

[0176] Example 42

[0177] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 52 h, while all other reaction conditions remained the same. After the reaction was completed and subjected to the same post-processing steps, polyaryl ketone materials were obtained. Specific experimental results are shown in Table 3.

[0178] Example 43

[0179] The procedure was performed according to the method described in Example 29, except that the reaction time was extended to 72 h, while all other reaction conditions remained the same. After the reaction was completed and the same post-processing steps were performed, polyaryl ketone materials were obtained. The specific experimental results are shown in Table 3.

[0180] Table 3

[0181]

[0182] Examples 29-43 are for screening polymerization reaction times, with a reaction time of 16 h being optimal.

[0183] Example 44

[0184] The procedure was performed according to the method described in Example 9, except that the reaction temperature was controlled at 50°C. o C. The reaction solvent used was N-methylpyrrolidone (NMP, 15 mL) that had undergone strict dehydration treatment. The types and amounts of the other reactants, the organometallic strong base used, and the post-treatment steps were the same as in Example 9.

[0185] After the reaction was completed, the material was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone material. Gel permeation chromatography analysis confirmed the formation of the target polymer. The results are shown in Table 4.

[0186] Example 45

[0187] The procedure was performed according to the method described in Example 44, except that the reaction solvent was replaced with dehydrated dimethylimidazolinone (DMI, 15 mL), and the other reaction conditions were the same as in Example 44.

[0188] After the reaction was complete, the product was obtained by treating it in the same way. Analysis showed that a polymer material was formed in the reaction system. The results are shown in Table 4.

[0189] Example 46

[0190] The procedure was performed according to the method described in Example 44, except that the reaction solvent was replaced with dehydrated N,N-dimethylacetamide (DMAc, 15 mL), and the other reaction conditions were the same as in Example 44.

[0191] After the reaction was complete, the product was obtained by treating it in the same way. Analysis showed that a polymer material was formed in the reaction system. The results are shown in Table 4.

[0192] Example 47

[0193] The procedure was performed according to the method described in Example 44, except that the reaction solvent was replaced with dehydrated tetrahydrofuran (THF, 15 mL), and the other reaction conditions were the same as in Example 44.

[0194] After the reaction was complete, the product was obtained by treating it in the same way. Analysis showed that a polymer material was formed in the reaction system. The results are shown in Table 4.

[0195] Example 48

[0196] The procedure was performed according to the method described in Example 44, except that the reaction solvent was replaced with dehydrated toluene (15 mL), and the other reaction conditions were the same as in Example 44.

[0197] After the reaction was complete, the product was obtained by treating it in the same way. Analysis showed that a polymer material was formed in the reaction system. The results are shown in Table 4.

[0198] Table 4

[0199]

[0200] Examples 44-48 show the screening of solvents for the polymerization reaction, in which DMF was the optimal solvent.

[0201] Example 49

[0202]

[0203] The procedure was performed according to the method described in Example 24, except that the aryl diketone monomer was replaced with an aryl diketone compound containing an ether linkage (Formula I-2, 3 mmol), while the other reaction conditions remained the same. After the reaction, the mixture was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone material. Gel permeation chromatography analysis confirmed the formation of the target polymer. Specific experimental results are shown in Table 5.

[0204] Example 50

[0205]

[0206] The procedure was performed according to the method described in Example 24, except that the aryl diketone monomer used was an aryl diketone compound containing a peroxy bond structure (Formula I-3, 3 mmol), while the other reaction conditions remained the same. After the reaction, the mixture was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone material. Gel permeation chromatography analysis confirmed the formation of the target polymer. Specific experimental results are shown in Table 5.

[0207] Example 51

[0208]

[0209] The procedure was performed according to the method described in Example 24, except that the aryl diketone monomer was replaced with an aryl diketone compound linked by an alkylene chain (Formula I-4, 3 mmol), while the other reaction conditions remained the same. After the reaction, the mixture was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone material. Gel permeation chromatography analysis confirmed the formation of the target polymer. Specific experimental results are shown in Table 5.

[0210] Example 52

[0211]

[0212] The procedure was performed according to the method described in Example 24, except that the aryl diketone monomer used was an aryl diketone compound 5-1e (formula I-5, 3 mmol) containing a flexible ether chain structure, while the other reaction conditions remained the same. After the reaction, the mixture was quenched, extracted, and purified in the same manner to obtain a linear polyaryl ketone material. Gel permeation chromatography analysis confirmed the formation of the target polymer. Specific experimental results are shown in Table 5.

[0213] Example 53

[0214]

[0215] The procedure was performed according to the method described in Example 24, except that the aryl monomer used was a trifunctional aryl polyketone compound (Formula I-6, 4.5 mmol), and the molar amount of the reactants was adjusted accordingly, while the other reaction conditions remained the same. After the reaction was completed, the polyfunctional polyaryl ketone material was obtained by processing it in the same manner. Specific experimental results are shown in Table 5.

[0216] Example 54

[0217]

[0218] The procedure was performed according to the method described in Example 24, except that the aryl polyketone monomer was replaced with a three-armed star-shaped aryl polyketone compound (Formula I-7, 4.5 mmol). After the reaction, the mixture was treated in the same manner to obtain the star-shaped polyaryl ketone material. Specific experimental results are shown in Table 5.

[0219] Example 55

[0220]

[0221] The procedure was performed according to the method described in Example 24, except that the aryl polyketone monomer used was a three-arm aryl polyketone compound (Formula I-8, 4.5 mmol) containing heteroatoms. After the reaction, the material was treated in the same manner to obtain the polyaryl ketone material. Specific experimental results are shown in Table 5.

[0222] Example 56

[0223]

[0224] The procedure was performed according to the method described in Example 24, except that the aryl polyketone monomer was replaced with a four-armed aryl polyketone compound (Formula I-9, 6 mmol). After the reaction, the compound was treated in the same manner to obtain a multi-armed polyaryl ketone material. Specific experimental results are shown in Table 5.

[0225] Example 57

[0226]

[0227] The procedure was performed according to the method described in Example 24, except that the aryl diketone monomer used was an aryl diketone compound with a small aromatic skeleton (Formula I-10, 3 mmol). After the reaction, the material was treated in the same manner to obtain the polyaryl ketone material. Specific experimental results are shown in Table 5.

[0228] Example 58

[0229]

[0230] The procedure was performed according to the method described in Example 24, except that the aryl diketone monomer was replaced with an aryl diketone compound with a p-phenylene structure (Formula I-11, 3 mmol). After the reaction, the material was treated in the same manner to obtain the polyaryl ketone material. Specific experimental results are shown in Table 5.

[0231] Example 59

[0232]

[0233] The procedure was performed according to the method described in Example 24, except that the aryl diketone monomer used was an aryl diketone compound containing a heterocyclic structure (Formula I-12, 3 mmol). After the reaction, the material was treated in the same manner to obtain the polyaryl ketone material. Specific experimental results are shown in Table 5.

[0234] Example 60

[0235]

[0236] The procedure was performed according to the method described in Example 50, except that the diester comonomer used was diethyl terephthalate (Formula II-2, 3 mmol), which underwent a Claisen polycondensation reaction with an aryl diketone monomer (Formula I-3, 3 mmol) under alkaline conditions. After the reaction, the mixture was quenched, extracted, and purified in the same manner to obtain the polyaryl ketone material. Specific experimental results are shown in Table 5.

[0237] Example 61

[0238]

[0239] The procedure was performed according to the method described in Example 60, except that the diester comonomer was replaced with diethyl cyclohexanedicarboxylate (Formula II-3, 3 mmol), while the other reaction conditions remained unchanged.

[0240] After the reaction was completed, the polyaryl ketone material was obtained by treating it in the same way, indicating that the method of the present invention is applicable not only to aromatic diesters, but also to alicyclic diester monomers. Specific experimental results are shown in Table 5.

[0241] Table 5

[0242]

[0243] The following application example, based on the polyaryl ketones prepared in the aforementioned embodiments, uses a Baeyer-Villiger oxidation reaction to convert some ketone groups in the polymer backbone into ester groups, thus preparing a polyaryl ketone ester material containing ester bonds. Subsequently, the polyaryl ketone ester material is subjected to hydrolysis to verify its controllable degradation behavior under external conditions, including backbone breakage or molecular weight reduction. This process endows the polyaryl ketone material with potential degradability and chemical recycling capabilities, and provides an important pathway for subsequent functional modification.

[0244] Unless otherwise stated, the polyaryl ketone raw materials used in the following examples are representative linear polyaryl ketone materials prepared according to the method described in Example 50, and the other experimental conditions not explicitly stated are conventional conditions in the art.

[0245]

[0246] Application Example 1

[0247] The polyaryl ketone (1.0 g) obtained in Example 50 was dissolved in chlorobenzene (20 mL) and stirred in an ice-water bath to form a homogeneous solution. Then, a peracetic acid solution (0.3 molar equivalents based on the ketone groups in the polymer) was slowly added, controlling the addition rate to avoid violent exothermic reactions. After the addition was complete, the reaction system was brought to room temperature and stirred continuously for 24 h to allow some of the ketone groups in the polyaryl ketone backbone to undergo Baeyer–Villiger oxidation.

[0248] After the reaction was completed, a saturated sodium bicarbonate solution was added to the reaction system for quenching, and residual oxidant was removed by washing with water. Subsequently, solvent extraction, drying, and depressurization were performed to remove the solvent, yielding a partially esterified polyaryl ketone ester material.

[0249] Infrared spectroscopy analysis revealed a new ester carbonyl absorption peak while the original ketone carbonyl absorption peak weakened, indicating that the Baeyer–Villiger oxidation reaction was successfully carried out (Figure 3).

[0250] Application Example 2

[0251] The procedure was carried out according to the method described in Application Example 1, except that the amount of peracetic acid used was 0.1 equivalents relative to the molar ratio of ketone groups in the polymer, while the other reaction conditions remained the same.

[0252] After the reaction was completed, the polyaryl ketone ester material with a low degree of oxidation was obtained by processing it in the same way.

[0253] Application Example 3

[0254] The procedure was carried out according to the method described in Example 60, except that the amount of peracetic acid used was 0.2 equivalents relative to the molar ratio of ketone groups in the polymer, while the other reaction conditions remained the same.

[0255] After the reaction was completed, the polyaryl ketone ester material with a moderate degree of oxidation was obtained by treating it in the same way.

[0256] Application Example 4

[0257] The procedure was carried out according to the method described in Example 60, except that the amount of peracetic acid used was 0.5 equivalents relative to the molar ratio of ketone groups in the polymer, while the other reaction conditions remained the same.

[0258] After the reaction was completed, the polyaryl ketone ester material with a high degree of oxidation was obtained by processing it in the same way.

[0259] Application Example 5

[0260] The polyaryl ketone (1.0 g) obtained in Example 50 was dissolved in chlorobenzene, and m-chloroperoxybenzoic acid (m-CPBA, 0.3 molar equivalents based on the ketone groups in the polymer) was slowly added under ice-water bath conditions. After the addition was complete, the reaction system was stirred continuously at room temperature for 24 h.

[0261] After the reaction was completed, the material was quenched, washed and purified according to the method described in Application Example 1 to obtain the Baeyer–Villiger oxidative modified polyaryl ketone ester material.

[0262] Application Example 6

[0263] The polyaryl ketone (1.0 g) obtained in Example 50 was added to acetic acid (20 mL) to form a homogeneous system under stirring. Subsequently, an aqueous hydrogen peroxide solution (30 wt%, with a molar ratio of 0.3 equivalents based on the ketone groups in the polymer) was slowly added under controlled temperature conditions, and the reaction was continuously stirred under acidic conditions for 24 h to allow some of the ketone groups in the polyaryl ketone backbone to undergo Baeyer–Villiger oxidation.

[0264] After the reaction was completed, an appropriate amount of deionized water was added to the system for dilution, and residual oxidants and acidic substances were removed by washing with water. Subsequently, solvent extraction, drying, and depressurization were performed to remove the solvent, yielding a partially esterified polyaryl ketone ester material.

[0265] Application Example 7

[0266] The polyaryl ketone material prepared in Example 51 was subjected to Baeyer–Villiger oxidation reaction according to the method described in Application Example 5.

[0267] After the reaction was completed, the polyaryl ketone ester material with the corresponding structure was obtained by processing it in the same way.

[0268] Application Example 8-16

[0269] The experimental procedure was the same as in Application Example 7, except that the polyaryl ketone material prepared in Example 51 was replaced with the polyaryl ketone materials prepared in Examples 52, 53, 54, 55, 56, 57, 58, 59, and 60, respectively.

[0270] Application Example 17

[0271]

[0272] The polyaryl ketone ester material (0.3 g) obtained in Application Example 5 was added to a mixed solvent of tetrahydrofuran and deionized water. Dilute hydrochloric acid solution was then added under stirring to make the system acidic. The mixture was then heated to 60 °C. o The reaction was continued at C for 24 h, causing the ester bonds in the polymer backbone to undergo hydrolysis.

[0273] After the reaction, the polymer product or low molecular weight fragments with significantly reduced molecular weight were obtained through neutralization, washing with water, and drying. 78.5 mg of small molecule benzoic acid derivatives were recovered, with a yield of 33%. This indicates that acidic conditions can induce hydrolytic degradation of polyaryl ketone esters (Figures 4-5).

[0274] The following application examples demonstrate how functionalization and modification reactions are performed on the polyaryl ketone or polyaryl ketone ester materials prepared in the foregoing examples to further convert the ketone groups in the polymer backbone into oxime or imine structures, thereby preparing a series of polyaryl ketone derivatives with diverse structures and tunable functions.

[0275] Unless otherwise stated, the polyaryl ketone raw materials used in the following examples are representative linear polyaryl ketone materials prepared according to the method described in Example 50, and the other experimental conditions not explicitly stated are conventional conditions in the art.

[0276] Application Example 18

[0277]

[0278] The polyaryl ketone (1.0 g) obtained in Example 50 was dissolved in N,N-dimethylformamide (DMF, 20 mL) to form a homogeneous system under stirring. Hydroxylamine hydrochloride (1.2 molar equivalents based on the ketone groups in the polymer) and a suitable amount of alkaline reagent were then added to bring the system to a weakly alkaline condition. The mixture was then stirred at 60 °C. o The reaction was continuously stirred at C for 24 h to induce oximation of the ketone groups in the polyaryl ketone backbone with hydroxylamine.

[0279] After the reaction was completed, the reaction solution was poured into a large amount of deionized water to precipitate the solid. After filtration, washing and drying, polyaryl ketoxime material was obtained.

[0280] Infrared spectroscopy analysis revealed novel characteristic absorption peaks associated with the oxime group in the polymer, indicating that the oxime reaction was successfully carried out (Figure 6a).

[0281] Application Example 19

[0282] The procedure is performed according to the method described in Application Example 18, except that hydroxylamine hydrochloride is replaced with hydroxylamine sulfate or a derivative thereof, while the other reaction conditions remain the same.

[0283] After the reaction was completed and the same post-processing steps were performed, polyaryl ketoxime materials were obtained, indicating that the method of the present invention has good applicability to different oxime reagents.

[0284] Application Example 20

[0285]

[0286] The polyaryl ketone (1.0 g) obtained in Example 50 was dissolved in an appropriate amount of polar solvent, and hexamethylenediamine (1.0 equivalent based on the ketone groups in the polymer by molar ratio) was added. The mixture was stirred continuously under heating conditions to allow the ketone groups and amine groups in the polyaryl ketone backbone to undergo a condensation reaction to generate an imine structure.

[0287] After the reaction was completed, the polyaryl ketone imine material was obtained by solvent removal, water washing and drying (Figure 6b).

[0288] Application Example 21

[0289] The procedure was performed according to the method described in Application Example 20, except that hexamethylenediamine was replaced with pentamethylenediamine, while the other reaction conditions remained the same. After the reaction was completed and followed by the same post-treatment steps, a polyaryl ketone imine material was obtained.

[0290] Application Example 22

[0291] The procedure was performed according to the method described in Application Example 20, except that hexamethylenediamine was replaced with heptanediamine, while the other reaction conditions remained the same. After the reaction was completed and followed by the same post-treatment steps, a polyaryl ketone imine material was obtained.

[0292] Application Example 23

[0293] The polyaryl ketone material prepared in Example 51 was subjected to an oxime reaction according to the method described in Application Example 20. After the reaction was completed, the corresponding functionalized polyaryl ketone derivative was obtained by processing in the same manner.

[0294] Application Example 24-32

[0295] The experimental procedure was the same as in Application Example 23, except that the polyaryl ketone material prepared in Example 51 was replaced with the polyaryl ketone materials prepared in Examples 52, 53, 54, 55, 56, 57, 58, 59, and 60, respectively.

[0296] This invention provides a method for constructing polyaryl ketone materials and controlling the main chain modification based on Claisen polycondensation. The method achieves a one-step synthesis of polyaryl ketone materials under mild conditions by polycondensation of aryl diketones with aryl or alicyclic diesters under the action of a strong organometallic base. This method offers controllable process conditions, a wide range of applicable substrates, and the ability to construct polyaryl ketone materials with various topologies, including linear, star-shaped, and multi-arm structures.

[0297] Building upon this foundation, this invention further introduces the Baeyer–Villiger oxidation reaction to controllably transform the ketone groups in the polyaryl ketone backbone, preparing polyaryl ketone ester materials containing ester bonds. This achieves a structural upgrade of polyaryl ketone materials from highly stable engineering plastics to potentially degradable or recyclable materials. Simultaneously, through oxime and ketamine condensation reactions, the polyaryl ketone or polyaryl ketone ester materials are functionalized by introducing oxime groups or imines into the polymer backbone, significantly expanding the structural diversity and chemical reactivity of the materials.

[0298] The polyaryl ketones and their derivatives obtained by this invention possess excellent mechanical properties, structural designability, and potential for subsequent functionalization. They can be widely used in high-performance engineering plastics, biodegradable materials, functional membrane materials, and recyclable chemical recycling systems, and have significant scientific value and promising industrial application prospects.

[0299] The above detailed description of the preferred embodiments of the present invention illustrates the preferred methods. However, the scope of the present invention is not limited thereto. Within the technical concepts and design principles covered by the present invention, any simple modifications and adjustments made based on the technical solutions of the present invention, as well as the combination or reconfiguration of the various technical features in any other suitable form, should be considered as included in the content disclosed in the present invention and also fall within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing polyaryl ketones via Claisen polycondensation, characterized in that, The process includes the following steps: under inert gas protection, an aryl diketone compound is mixed with an aryl or cycloalkyl diester compound, then an organometallic strong base is added, and under anhydrous conditions, a polar amide solvent is added and stirred to induce a Claisen polycondensation reaction. The reaction solution is poured into acidified water to precipitate, and the precipitate is separated, washed, and dried to obtain polyaryl ketone.

2. The method for preparing polyaryl ketones via Claisen polycondensation according to claim 1, characterized in that, The structure of the aryl diketone compound is selected from one of the following: linear aryl ether ketones, diaryl ketones containing alkyl chains, tridentate or tetradentate star-shaped aryl polyketones, and aryl diketones with para- or meta-substituted aromatic rings.

3. The method for preparing polyaryl ketones via Claisen polycondensation according to claim 1, characterized in that, The aryl or cycloalkyl diester compound is selected from one of isophthalate diester, terephthalate diester, isomer of aryl diester, and cyclohexanedicarboxylate diester.

4. The method for preparing polyaryl ketones via Claisen polycondensation according to claim 1, characterized in that, The molar ratio of the aryl diketone compound to the aryl or cycloalkyl diester compound is 1:(0.5-1.5).

5. The method for preparing polyaryl ketones via Claisen polycondensation according to claim 1, characterized in that, The organometallic strong base is selected from at least one of potassium tert-butoxide, sodium tert-butoxide, potassium methoxide, and sodium methoxide, and the amount of the organometallic strong base is 1.5-5 times the molar amount of the aryl diketone compound.

6. The method for preparing polyaryl ketones via Claisen polycondensation according to claim 1, characterized in that, The polar amide solvent is one or more of N,N-dimethylformamide (DMF), dimethylimidazolinone (DMI), and N-methylpyrrolidone (NMP).

7. The method for preparing polyaryl ketones via Claisen polycondensation according to claim 1, characterized in that, The Claysen polycondensation reaction temperature is 20-180°C. o C, the reaction time is 2-72 hours.

8. The polyaryl ketone prepared by the method of preparing polyaryl ketone by Claysen polycondensation according to claim 1 is further subjected to Bayer-Villiger oxidation by a peroxidant to generate at least partially esterified polyaryl ketone ester.

9. The polyaryl ketone prepared by the method of preparing polyaryl ketone by Claysen polycondensation according to claim 1 is further subjected to ketamine condensation or oxime reaction with diamine, hydroxylamine or its derivatives to prepare polyaryl ketone imine or polyaryl ketone oxime.

10. The use of the polyaryl ketone or its derivative obtained according to any one of claims 1-9 in biodegradable thermoplastic materials, engineering plastics, membrane materials, radiation-resistant materials or recyclable chemical recycling systems.

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