Main chain type fluorine-containing active ester as well as preparation method and application thereof

Abstract

The invention provides main chain type fluorine-containing active ester as well as a preparation method and application thereof, and belongs to the field of electronic material processing. The main chain type fluorine-containing active ester curing agent is prepared, and a resin cured product formed by curing the main chain type fluorine-containing active ester curing agent and epoxy resin has the advantages of low dielectric constant, low dielectric loss, high glass transition temperature, excellent mechanical property and excellent heat resistance. The main chain type fluorine-containing active ester curing agent and the cured product thereof are suitable for the fields of high-performance electronic packaging materials and high-performance printed circuit boards, and have wide application prospects.

Description

Technical Field

[0001] The invention belongs to the field of electronic material processing, and in particular relates to a main chain type fluorine-containing active ester and a preparation method and application thereof. Background Art

[0002] With the rapid development of 5G communication technology, in recent years, with the continuous development of high-frequency communication field, electronic equipment has been continuously accelerated and miniaturized, which has put forward higher performance requirements for insulation materials used for packaging. However, thermosetting epoxy resins prepared with traditional amine or anhydride curing agents have high dielectric constants (Dk) and dielectric losses (Df), which limit their further application in the field of high-frequency and high-speed communication. Therefore, the development of epoxy resins with ultra-low dielectric losses has received more and more attention.

[0003] There is a literature (J. Zhang, L. Dang, F. Zhang, K. Zhang, Q. Kong, J. Gu, Effect of the Structure of Epoxy Monomers and Curing Agents: Toward Making Intrinsically Highly Thermally Conductive and Low-Dielectric Epoxy Resins [J]. JACS Au (2023) 3424–3435.) reporting that dielectric properties can be improved by introducing low polar structures, such as CF bonds, into epoxy resins. However, the thermal decomposition temperature (T d5％ ) is low, heat resistance is poor, glass transition temperature (T g ) is low, and the dielectric properties cannot meet the requirements of high-frequency insulating electronic packaging materials.

[0004] Studies have reported that active esters can improve the dielectric properties of cured resins as curing agents for epoxy resins. Currently, active ester compounds are usually obtained by esterifying the hydroxyl groups of phenol novolac. However, due to the transfer of ester groups to the side chains of the molecules during the reaction between active esters and epoxy resins, the crosslinking density of the cured resin is not high, resulting in poor heat resistance and low glass transition temperature (CN 110511360 A).

[0005] Therefore, developing an epoxy curing agent for preparing a resin cured product with high cross-linking density, good heat resistance and excellent dielectric properties to meet the application requirements of high-frequency insulating electronic packaging materials is a research focus in this field. Summary of the invention

[0006] In order to solve the defects of the prior art, the object of the present invention is to provide a main chain type fluorine-containing active ester and a preparation method and use thereof.

[0007] The present invention provides a main chain type fluorine-containing active ester, and its preparation method comprises the following steps:

[0008] (1) reacting a bisphenol compound, a bisacyl chloride compound and a base to obtain a mixture;

[0009] (2) reacting the acyl chloride monomer with the mixture in step (1) to obtain a main-chain fluorine-containing active ester.

[0010] Furthermore, in step (1), the molar ratio of the bisphenol compound, the bisacyl chloride compound and the base is 1:0.3-1:2-2.5; the bisphenol compound is selected from bisphenol A, bisphenol F, bisphenol AF, bisphenol S, bisphenol B, bisphenol Z or dimethyl bisphenol A; the bisacyl chloride compound is an aliphatic bisacyl chloride compound or an aromatic bisacyl chloride compound; the base is an organic base or an inorganic base; the solvent of the reaction is an organic solvent; the reaction temperature is 40-60°C and the reaction time is 2-4h;

[0011] In step (2), the molar ratio of the bisphenol compound to the acyl chloride monomer in step (1) is 1:1-1.5; the acyl chloride monomer is an aliphatic acyl chloride monomer or an aromatic acyl chloride monomer; the solvent of the reaction is an organic solvent; the reaction temperature is 70-90°C and the reaction time is 3-5h.

[0012] Furthermore, in step (1), the molar ratio of the bisphenol compound, the bisacyl chloride compound and the base is 1:0.7:2.2; the bisphenol compound is bisphenol AF; the bisacyl chloride compound is isophthaloyl chloride; the base is triethylamine; the solvent of the reaction is butanone; the reaction temperature is 50°C and the reaction time is 3 hours;

[0013] In step (2), the molar ratio of the bisphenol compound to the acyl chloride monomer in step (1) is 1:1.2; the acyl chloride monomer is benzoyl chloride; the solvent of the reaction is butanone; the reaction temperature is 80° C. and the reaction time is 4 hours.

[0014] Furthermore, after the reaction of step (2) is completed, the following purification step is also included: after the reaction is completed, the mixture is filtered, an ethanol / water mixture is added to the filtrate for precipitation, the precipitate is collected by filtration, and dried to obtain a main chain type fluorine-containing active ester.

[0015] Furthermore, the main chain type fluorine-containing active ester is a compound having the following structure:

[0016]

[0017] Here, n represents the degree of polymerization.

[0018] The present invention also provides a method for preparing the main chain type fluorine-containing active ester, which comprises the following steps: reacting a bisphenol compound, a bisacyl chloride compound and a base to obtain a mixture; and then reacting an acyl chloride monomer with the mixture to obtain a main chain type fluorine-containing active ester.

[0019] The present invention also provides the use of the main chain type fluorine-containing active ester in preparing a resin curing agent.

[0020] The present invention also provides a resin cured product, which is a product obtained by a curing reaction using the main chain type fluorine-containing active ester, resin and catalyst as raw materials.

[0021] Furthermore, the resin is an epoxy resin, the molar ratio of the epoxy group in the epoxy resin to the ester group in the main chain fluorine-containing active ester is 1:1-1.5; the weight percentage of the catalyst to the resin is 0.5-1.5wt%; the catalyst is an acidic catalyst or a basic catalyst; and the solvent of the reaction is an organic solvent.

[0022] Furthermore, the epoxy resin is a dicyclopentadiene epoxy resin; the catalyst is 4-dimethylaminopyridine; the molar ratio of the epoxy group in the epoxy resin to the ester group in the main chain fluorine-containing active ester is 1:1.2; and the weight percentage of the catalyst to the resin is 1wt%.

[0023] Furthermore, the curing conditions are: curing at 80°C for 30 minutes, curing at 120°C for 1 hour, curing at 150°C for 1 hour, curing at 180°C for 2 hours and curing at 200°C for 1 hour.

[0024] The present invention also provides the use of the above-mentioned resin cured product in preparing electronic packaging materials and printed circuit boards.

[0025] The present invention has achieved the following beneficial effects:

[0026] The present invention prepares a main chain type fluorine-containing active ester curing agent, and a resin cured product formed by curing the main chain type fluorine-containing active ester curing agent with an epoxy resin has low dielectric constant, low dielectric loss, excellent mechanical properties and excellent heat resistance. The main chain type fluorine-containing active ester curing agent and the cured product thereof are suitable for the fields of high-performance electronic packaging materials and high-performance printed circuit boards, and have broad application prospects.

[0027] The T values ​​of the epoxy resin cured products DCPD / AE-1, DCPD / AE-2 and DCPD / AE-3 of the present invention are as follows: d5％ They are 336℃, 353℃ and 359℃ respectively, the dielectric constants are 2.76, 3.11 and 2.76 respectively, and the dielectric losses are 7.11‰, 7.44‰ and 7.36‰ respectively.

[0028] The T of epoxy resin prepared in the literature (J. Zhang, L. Dang, F. Zhang, K. Zhang, Q. Kong, J. Gu, Effect of the Structure of Epoxy Monomers and Curing Agents: Toward Making Intrinsically Highly Thermally Conductive and Low-Dielectric Epoxy Resins [J]. JACS Au (2023) 3424–3435.) d5％ They are 249.8°C and 288.4°C respectively, the dielectric constant is 2.72, and the dielectric loss is 0.015 and 0.042. It can be seen that compared with the epoxy resin reported in the document, the heat resistance and dielectric properties of the epoxy resin cured product of the present invention are significantly improved.

[0029] The dielectric constant of the epoxy resin prepared in CN 110511360 A is 3.7-4.2, and the dielectric loss is 0.0059-0.0068. It can be seen that compared with the epoxy resin reported in CN 110511360 A, the dielectric constant of the epoxy resin cured product of the present invention is significantly lower, which is conducive to significantly improving the propagation speed of the signal.

[0030] Obviously, according to the above contents of the present invention, in accordance with common technical knowledge and customary means in the art, without departing from the above basic technical ideas of the present invention, other various forms of modification, replacement or change may be made.

[0031] The above contents of the present invention are further described in detail below through specific implementation methods in the form of examples. However, this should not be understood as the scope of the above subject matter of the present invention being limited to the following examples. All technologies realized based on the above contents of the present invention belong to the scope of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 The preparation flow chart of thermosetting epoxy resin film.

[0033] Figure 2 DSC curves of three active ester-cured DCPD epoxy resins (a) and DSC curve of thermosetting epoxy resin (b).

[0034] Figure 3 The infrared spectra (a) and nuclear magnetic resonance (NMR) spectra (b) of three fluorine-containing active esters with different main chain types, AE-1, AE-2 and AE-3.

[0035] Figure 4The figure shows the molecular weight and distribution curves of three different main chain fluorine-containing active esters.

[0036] Figure 5 Infrared spectra of active ester-cured DCPD epoxies of AE-1 (a), AE-2 (b) and AE-3 (c).

[0037] Figure 6 The tensile strength and tensile stress-strain curve of epoxy cured products.

[0038] Figure 7 Storage modulus (a) and tanδ (b) curves of thermosetting epoxy resin. DETAILED DESCRIPTION

[0039] The raw materials and equipment used in the present invention are all known products, which are obtained by purchasing commercially available products.

[0040] 4,4′-(Hexafluoroisopropylidene)diphenol (also known as bisphenol AF), isophthaloyl chloride, benzoyl chloride, DMAP and triethylamine were purchased from Adamas; DCPD epoxy resin (DPNE1501L, epoxy value: 273 g / mol) was a product of Hunan Jiashengde Materials Technology Co., Ltd.; ethanol and butanone were purchased from Chengdu Xilong Technology Co., Ltd. The above materials were used directly without treatment.

[0041] The "room temperature" referred to in the present invention is 25±5°C.

[0042] Example 1. Preparation of main chain fluorinated active ester

[0043] Add 4,4′-(hexafluoroisopropylidene)diphenol (0.05mol, 16.81g), isophthaloyl chloride (0.025mol, 5.1g) and 100ml butanone to a 500ml two-necked flask equipped with a dropping funnel and a nitrogen protection device, and stir and dissolve at 25°C. Dissolve triethylamine (0.11mol, 11.13g) in 50ml butanone, slowly drop it into the reactant within 1h, and heat it to 50°C for 3h after the addition is complete. After the reaction is completed, cool the reactant to room temperature, dissolve benzoyl chloride (0.06mol, 8.43g) in 50ml butanone, slowly drop it into the reactant within 1h, and heat it to 80°C for 4h after the addition is complete. After the reaction, the mixture was filtered to obtain a light yellow filtrate, which was added dropwise to about 1000 ml of an ethanol / water mixture to produce a large amount of white precipitate. The precipitate was collected by filtration after standing, and the precipitate was washed three times with ethanol. The white solid was then dried in a vacuum oven at 80°C for 12 hours to obtain the final product with a yield of 84.3%, which was named AE-1. The synthetic route is as follows:

[0044]

[0045] Example 2: Preparation of main chain fluorinated active ester

[0046] The preparation method of reference example 1 is different only in that the amount of isophthaloyl chloride is changed to 0.03 mol, and the final product is obtained with a yield of 86.2%, which is named AE-2.

[0047] Example 3: Preparation of main chain fluorinated active ester

[0048] The preparation method of reference example 1 is different only in that the amount of isophthaloyl chloride is changed to 0.035 mol, and the final product is obtained with a yield of 85.7%, which is named AE-3.

[0049] Example 4: Preparation of Thermosetting Epoxy Resin Cured Material

[0050] DCPD epoxy resin, main chain fluorinated active ester (AE-1) and 4-dimethylaminopyridine (DMAP) were dissolved in butanone to prepare a glue solution with a solid content of 60wt%. The molar ratio of epoxy groups in DCPD epoxy resin to ester groups in main chain active ester was controlled to be 1:1.2, and the amount of catalyst DMAP added was 1wt% of the mass of DCPD epoxy resin. The glue solution was uniformly cast onto the PET film using a film coater, and cured in sequence according to the temperature program of curing at 80℃ for 30min, 120℃ for 1h, 150℃ for 1h, 180℃ for 2h and 200℃ for 1h, and finally an epoxy resin film was obtained, which was named DCPD / AE-1.

[0051] Example 5. Preparation of Thermosetting Epoxy Resin Cured Material

[0052] The preparation method of Reference Example 4 is different in that the main chain type fluorine-containing active ester AE-1 is replaced by the main chain type fluorine-containing active ester AE-2 to obtain an epoxy resin film, which is named DCPD / AE-2.

[0053] Example 6: Preparation of Thermosetting Epoxy Resin Cured Material

[0054] The preparation method of Reference Example 4 is different in that the AE-1 main chain type fluorinated active ester is replaced by the AE-3 main chain type fluorinated active ester to obtain an epoxy resin film, which is named DCPD / AE-3.

[0055] The beneficial effects of the present invention are demonstrated by experimental examples below.

[0056] Experimental Example 1: Structural Characterization and Performance Determination of Active Ester Curing Agent and Thermosetting Epoxy Resin Cured Material

[0057] 1. Test instruments and characterization methods

[0058] Infrared spectrum test: The active ester curing agent test method adopts KBr tablet method, and the resin curing material adopts ATR reflection method with a resolution of 1cm -1 , infrared scanning range is 400~4000cm -1 The infrared spectra of the samples were measured using a Nicolet 570 (Nicolet, USA) infrared spectrometer.

[0059] Nuclear magnetic resonance spectroscopy test: The active ester curing agent nuclear magnetic resonance test adopts Bruker AV II (Bruker, Germany) nuclear magnetic resonance spectrometer, tests H spectrum, uses deuterated chloroform as the test solvent, and the test frequency is 400 Hz.

[0060] Differential Scanning Calorimetry Test: The DSC curve of the samples was measured by using a DSC 204F1 Iris (Netzsch, Germany) differential scanning calorimeter. The test atmosphere was N2, the test temperature range was 40-200°C, and the heating rate was 5°C / min.

[0061] Dynamic thermomechanical test: Q800 (TA, USA) dynamic thermomechanical analyzer was used to characterize the glass transition behavior of the epoxy film. The test frequency was 1 Hz, the test temperature range was 40-220 °C, the heating rate was 5 °C / min, and the test mode was tensile mode.

[0062] Mechanical properties test: The tensile properties of the epoxy film were tested using an Instron 5966 (Instron, USA) universal testing machine. The tensile strength was tested according to GB13022-91 standard by cutting the sample into rectangular strips at a test rate of 1 mm / min to obtain the tensile strength, tensile modulus and elongation at break.

[0063] Dielectric property test: The cured samples were tested by a resonant cavity (AET. Inc, Japan) and a vector network analyzer N5247A (Keysight Technologies, Malaysia). The test sample size was 8 cm × 8 cm film, the test temperature was 25 °C, and the test frequency was 10 GHz.

[0064] 2. Experimental results

[0065] 2.1 Curing conditions of main chain fluorinated active esters

[0066] The preparation process of thermosetting epoxy resin film is as follows Figure 1As shown. The uncured resin film was cured in sequence according to the temperature program of curing at 80°C for 30 minutes, curing at 120°C for 1 hour, curing at 150°C for 1 hour, curing at 180°C for 2 hours and curing at 200°C for 1 hour to obtain a thermosetting epoxy resin film. In order to determine whether the active ester can fully react with the epoxy group under this curing process, the three thermosetting films were subjected to DSC testing. The curing conditions are determined by the DSC curve, as shown in Figure 2 As shown in (a), it can be seen from the curve that the starting temperature of the curing reaction is between 120℃-140℃, and the peak temperature of the curing reaction is between 160℃-180℃, among which AE-1 active ester has a higher curing peak temperature than the other two active esters. Figure 2 As shown in (b), there is a step-like change in heat capacity in the curve, which corresponds to the corresponding glass transition temperature (Tg-DSC). In the temperature range of 40℃ to 200℃, the cured product does not show an exothermic peak, indicating that the above temperature program is appropriate for preparing thermosetting epoxy films.

[0067] 2.2 Structural characterization of main chain fluorinated active esters

[0068] The infrared spectra of active esters of AE-1, AE-2 and AE-3 are shown in Figure 3 As shown in (a), at 3076 cm -1 and 1420cm -1 The CH and CC vibration absorption peaks of the benzene ring appear at 1420 cm -1 The vibration absorption peak of CF appeared. This shows that the structure of bisphenol AF was successfully introduced into the active ester. The infrared spectra of the three active esters all have obvious ester characteristic absorption peaks at 1745cm -1 There is a strong C=O vibration absorption peak and a peak at 1170 cm -1 The CO vibration absorption peak appeared. The above indicated that the trifluoromethyl group and ester group were successfully introduced into the active ester.

[0069] In order to further determine the structures of the three active esters, their 1 H NMR spectrum, such as Figure 3 (b). All active hydrogens are located on the benzene ring, and their chemical shifts are between 7-9ppm. The characteristic absorption peaks at e, f and c correspond to the hydrogens on the benzene ring of benzoyl chloride, the characteristic absorption peaks at a, b and d correspond to the hydrogens on the benzene ring of isophthaloyl chloride, and the characteristic absorption peaks at h and g correspond to the hydrogens on the benzene ring of bisphenol AF. This indicates that the main chain type fluorinated active ester curing agents AE-1, AE-2 and AE-3 were successfully synthesized by the chain extension reaction of bisphenol AF compound with isophthaloyl chloride and the end-capping reaction of benzoyl chloride.

[0070] The molecular weight and distribution of the three active ester curing agents were characterized by GPC, as shown in Table 1. AE-1, AE-2 and AE-3 all have narrow molecular weight distributions. With the increase in the amount of isophthaloyl chloride, the molecular weight of the active ester increases continuously, and AE-3 has the highest molecular weight. In order to further determine the difference between the molecular weights of the three active esters, the molecular weight distribution curves of the three active esters were drawn and the mass fractions of the components with different polymerization degrees were calculated, as shown in Tables 2 and Figure 4 Nearly half of the components of AE-1 have a degree of polymerization less than 3, and the mass fractions of components with n≥3 in AE-2 and AE-3 are 64.17% and 70.42%, respectively. AE-3 has more components with high degree of polymerization than the other two active esters.

[0071] Table 1. GPC data of different active esters

[0072]

[0073] Table 2. Proportion of active esters with different polymerization degrees

[0074]

[0075] 2.3 Structural identification of thermosetting epoxy resins

[0076] In order to determine the degree of curing reaction between epoxy resin and active ester, FTIR spectroscopy was performed on DCPD epoxy resin and the cured resin, such as Figure 5 As shown. The absorption peak of the epoxy group in epoxy resin is at 917cm -1 The ester absorption peaks of the three active ester curing agents are at 1745 cm -1 At 1727 cm-1, the absorption peaks of epoxy groups in the prepared thermosetting epoxy resin disappeared, and the absorption peaks of ester groups were located at 1727 cm-1. -1 , 1724cm -1 and 1730cm -1 Compared with the active ester curing agent, different degrees of red shift occurred, indicating that the chemical environment of the ester group has changed significantly. The above proves that almost all the epoxy groups in the thermosetting epoxy resin participate in the reaction with the active ester, and the ester group is introduced into the cross-linking structure.

[0077] 2.4 Mechanical properties analysis of thermosetting epoxy resin

[0078] Mechanical properties are the most basic properties of materials. Figure 6 The mechanical properties of three epoxy resin cured products are shown. Among them, DCPD / AE-3 has the best mechanical strength and elongation at break, with a tensile strength of 84.1 MPa and an elongation at break of 5.94%. The relevant data are listed in Table 3.

[0079] Table 3. Mechanical properties of epoxy cured products

[0080]

[0081] 2.5 Dynamic mechanical properties analysis of thermosetting epoxy resin

[0082] Glass transition temperature (Tg) is an important parameter for evaluating the thermal properties of dielectric materials. The storage modulus and tanδ curves of three thermosetting epoxy resins were measured by DMA, such as Figure 7 As shown. The storage modulus of DCPD / AE-1, DCPD / AE-2 and DCPD / AE-3 at room temperature are very close (~2400MPa). As the temperature rises, the epoxy resin changes from the glass state to the rubber state, and the storage modulus suddenly decreases, corresponding to the glass transition. Compared with the other two epoxy resins, DCPD / AE-3 has the highest transition temperature and the highest storage modulus (15.86MPa) in the rubber platform area. From the tanδ curve, it can be seen that DCPD / AE-3 has the highest Tg-DMA (188℃). The relevant data are listed in Table 4.

[0083] 2.6 Thermal stability analysis of thermosetting epoxy resin

[0084] Since a lot of heat is generated in electronic devices, the thermal stability of dielectric materials is a very important property. The thermal stability of the cured resin was analyzed by TGA. Among them, DCPD / AE-3 has the highest T d5％ , is 358℃. The relevant data are listed in Table 4. This shows that it has excellent application potential in high heat-resistant electronic packaging materials.

[0085] 2.7 Analysis of Dielectric Properties of Thermosetting Epoxy Resins

[0086] In high-frequency communication devices, in order to ensure high-speed and high-quality signal transmission, low dielectric constant (Dk) and low dielectric loss (Df) are the top priorities for evaluating the dielectric properties of materials. Low Dk and low Df are conducive to increasing the propagation speed of signals and reducing the propagation loss of signals, respectively. The Dk and Df of thermosetting epoxy resin films were tested at a frequency of 10 GHz, and the relevant data are listed in Table 4. It can be seen that the three thermosetting epoxy resins all have low Dk and low Df.

[0087] Table 4. Dielectric properties, thermal stability and heat resistance data of epoxy resin cured products

[0088]

[0089] It can be seen from the above experimental results that the thermosetting epoxy resin prepared using the main chain fluorine-containing active ester of the present invention as a curing agent has low dielectric constant, low dielectric loss, high glass transition temperature, excellent mechanical properties and excellent heat resistance. Among them, compared with DCPD / AE-1 and DCPD / AE-2, DCPD / AE-3 prepared with AE-3 has the best mechanical strength and fracture growth rate, the highest glass transition temperature and the highest storage modulus, and the best thermal stability.

[0090] In summary, the present invention provides a main chain type fluorine-containing active ester and a preparation method and use thereof. The present invention prepares a main chain type fluorine-containing active ester curing agent, and the resin cured product formed by curing the main chain type fluorine-containing active ester curing agent with epoxy resin has low dielectric constant, low dielectric loss, high glass transition temperature, excellent mechanical properties and excellent heat resistance. The main chain type fluorine-containing active ester curing agent and the cured product thereof of the present invention are suitable for the fields of high-performance electronic packaging materials and high-performance printed circuit boards, and have broad application prospects.

Claims

1. A main chain type fluorine-containing active ester, characterized in that: Its preparation method comprises the following steps: (1) reacting a bisphenol compound, a bisacyl chloride compound and a base to obtain a mixture; (2) reacting the acyl chloride monomer with the mixture in step (1) to obtain a main-chain fluorine-containing active ester.

2. The main chain type fluorine-containing active ester according to claim 1, characterized in that: In step (1), the molar ratio of the bisphenol compound, the bisacyl chloride compound and the base is 1:0.3-1:2-2.5; the bisphenol compound is selected from bisphenol A, bisphenol F, bisphenol AF, bisphenol S, bisphenol B, bisphenol Z or dimethyl bisphenol A; the bisacyl chloride compound is an aliphatic bisacyl chloride compound or an aromatic bisacyl chloride compound; the base is an organic base or an inorganic base; the solvent of the reaction is an organic solvent; the reaction temperature is 40-60°C and the reaction time is 2-4h; In step (2), the molar ratio of the bisphenol compound to the acyl chloride monomer in step (1) is 1:1-1.5; the acyl chloride monomer is an aliphatic acyl chloride monomer or an aromatic acyl chloride monomer; the solvent of the reaction is an organic solvent; the reaction temperature is 70-90°C and the reaction time is 3-5h.

3. The method according to claim 2, characterized in that In step (1), the molar ratio of the bisphenol compound, the bisacyl chloride compound and the base is 1:0.7:2.2; the bisphenol compound is bisphenol AF; the bisacyl chloride compound is isophthaloyl chloride; the base is triethylamine; the solvent of the reaction is butanone; the reaction temperature is 50°C and the reaction time is 3 hours; In step (2), the molar ratio of the bisphenol compound to the acyl chloride monomer in step (1) is 1:1.2; the acyl chloride monomer is benzoyl chloride; the solvent of the reaction is butanone; the reaction temperature is 80° C. and the reaction time is 4 hours.

4. The main chain type fluorine-containing active ester according to claim 3, characterized in that: The main chain type fluorine-containing active ester is a compound having the following structure: Here, n represents the degree of polymerization.

5. A method for preparing the main chain type fluorine-containing active ester according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: reacting a bisphenol compound, a bisacyl chloride compound and a base to obtain a mixture; and then reacting an acyl chloride monomer with the mixture to obtain a main chain type fluorine-containing active ester.

6. Use of the main chain type fluorine-containing active ester according to any one of claims 1 to 4 in the preparation of a resin curing agent.

7. A cured resin product, characterized in that: The invention is a product obtained by curing reaction using the main chain type fluorine-containing active ester as claimed in any one of claims 1 to 4, a resin and a catalyst as raw materials.

8. The cured resin material according to claim 7, characterized in that: The resin is an epoxy resin, and the molar ratio of the epoxy group in the epoxy resin to the ester group in the main chain type fluorine-containing active ester is 1:1-1.5; the weight percentage of the catalyst to the resin is 0.5-1.5wt%; the catalyst is an acidic catalyst or a basic catalyst; and the solvent of the reaction is an organic solvent.

9. The cured resin material according to claim 8, characterized in that: The curing reaction conditions are: curing at 80°C for 30 minutes, curing at 120°C for 1 hour, curing at 150°C for 1 hour, curing at 180°C for 2 hours and curing at 200°C for 1 hour.

10. Use of the cured resin according to any one of claims 7 to 9 in the preparation of electronic packaging materials and printed circuit boards.

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