Crystalline polyarylene ether nitrile composite film and preparation method thereof

Abstract

The invention discloses a crystalline polyarylene ether nitrile composite film and a preparation method thereof, and belongs to the technical field of special high polymer materials. When the crystalline poly (arylene ether nitrile) composite film is prepared, low-molecular-weight poly (arylene ether nitrile) is doped into high-molecular-weight poly (arylene ether nitrile), a branched structure of the low-molecular-weight poly (arylene ether nitrile) can be used as a nucleation site to reduce the activation energy of ordered arrangement of a high-molecular-weight chain, and the end group of the branched structure and the nitrile group of the high-molecular-weight poly (arylene ether nitrile) form hydrogen-bond interaction, so that the crystalline poly (arylene ether nitrile) composite film is prepared. Molecular chains are induced to be piled in a specific direction, so that the crystallinity of the composite film is improved, and the crystalline polyarylene ether nitrile composite film with excellent performance is obtained. Besides, low-molecular-weight polyarylene ether nitrile is adopted to induce crystallization of a high-molecular-weight polyarylene ether nitrile matrix, disordered oscillation of dipoles is reduced due to regular arrangement of nitrile groups in a crystallization region of the obtained composite film, the constant of the obtained composite film is increased, and the dielectric loss of the film is reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of special polymer materials, and in particular relates to a crystalline polyarylethernitrile composite film and a preparation method thereof. Background Art

[0002] With the development of science and technology and social progress, the demand for films in aerospace, national defense, electronics and electrical, new energy, automobile manufacturing, optics and other fields has gradually increased, and the application conditions have become more demanding, with higher requirements for the dielectric properties, heat resistance, flame retardancy, etc. of the films. Polyarylethernitrile (PEN) has excellent dielectric properties, mechanical properties, flame retardancy, heat resistance, etc., which makes it stand out among many materials.

[0003] Polyarylethernitrile is divided into crystalline PEN and amorphous PEN according to the condensed state. Amorphous polyarylethernitrile is relatively simple to synthesize and easy to control; crystalline PEN is easy to precipitate during synthesis, which is relatively difficult to synthesize, but has better performance. Highly crystalline PEN has high strength, high modulus, and better heat resistance, which improves the crystallization of polyarylethernitrile and optimizes the performance of polyarylethernitrile. However, the crystallization of polyarylethernitrile is affected by many conditions and factors, such as the molecular weight of the matrix polyarylethernitrile resin itself, annealing temperature, cooling rate, nucleating agent, etc. Finding a preparation method that can promote the crystallization of polyarylethernitrile is particularly important for improving the performance of polyarylethernitrile. Summary of the invention

[0004] In view of the above-mentioned prior art, the present invention provides a crystalline poly(arylene ether nitrile) composite film and a preparation method thereof, so as to solve the technical problem of poor comprehensive performance of the poly(arylene ether nitrile) film in the prior art.

[0005] In order to achieve the above object, the technical solution adopted by the present invention is to provide a method for preparing a crystalline poly(arylene ether nitrile) composite film, comprising the following steps:

[0006] (1) Preparation of high molecular weight crystallizable poly(arylene ether nitrile):

[0007] Putting hydroquinone, resorcinol, 2,6-dichlorobenzonitrile and the first catalyst into a reaction container, adding the first mixed solvent to dissolve, then heating the resulting solution to 180-190° C., keeping the temperature for reaction for 1.5-3 hours to obtain a crude product, and then purifying the crude product to obtain a high molecular weight crystallizable polyarylethernitrile;

[0008] (2) Preparation of low molecular weight RS polyarylether nitrile resin

[0009] Putting resorcinol, 2,6-dichlorobenzonitrile and a second catalyst into a reaction container, adding a second mixed solvent to dissolve, then heating the resulting solution to 185-195° C., keeping the temperature for reaction for 2-3 hours to obtain a crude product, and then purifying the crude product to obtain a low molecular weight RS polyarylethernitrile resin;

[0010] (3) Preparation of crystalline poly(arylene ether nitrile) composite films

[0011] A high molecular weight crystallizable polyarylethernitrile and a low molecular weight RS polyarylethernitrile resin are mixed in a mass ratio of 50:1-5, and then the mixture is dissolved in N-methylpyrrolidone, and the obtained solution is heated to 140°C to obtain a hot solution; then the obtained hot solution is formed into a film by a casting method, and the heating program of the casting film forming process is: from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then heated to 100°C within 10 minutes, and kept at 100°C for 1 hour; then heated to 120°C within 10 minutes, and kept at 120°C for 1 hour; then heated to 160°C within 20 minutes, and kept at 160°C for 2 hours; then heated to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the heating program is completed, it is cooled to room temperature to obtain a crystalline polyarylethernitrile composite film.

[0012] Based on the above technical solution, the present invention can also be improved as follows.

[0013] Furthermore, after the film is cast in step (3), a heat treatment is performed. The heat treatment method is as follows: the film that has been cooled to room temperature after the heating program is completed is heated to 280°C within 1 hour, kept warm for 2 hours, and then naturally cooled to room temperature to obtain a crystalline polyarylethernitrile composite film.

[0014] Furthermore, the molar ratio of hydroquinone, resorcinol, 2,6-dichlorobenzonitrile and the first catalyst is 8:2:10:13; and the first catalyst is potassium carbonate.

[0015] Furthermore, the first mixed solvent is formed by mixing N-methylpyrrolidone and toluene in a volume ratio of 3:1; the total amount of hydroquinone, resorcinol, 2,6-dichlorobenzonitrile and the first catalyst to the first mixed solvent has a solid-liquid ratio of 1g:0.9~1.5ml.

[0016] Furthermore, the crude product in step (1) is purified by pouring the crude product into cold water to precipitate, crushing and filtering; then soaking the obtained powder in acetone, standing for 8 hours, then filtering, and then soaking the obtained powder in a dilute hydrochloric acid solution for 8 hours, and then washing it with pure water by boiling for 3 to 5 times; then placing the washed powder in a vacuum oven and drying it for 12 hours; the dilute hydrochloric acid solution is obtained by mixing hydrochloric acid with a concentration of 36% and water in a volume ratio of 1:100.

[0017] Furthermore, the molar ratio of resorcinol, 2,6-dichlorobenzonitrile and the second catalyst is 1:1:1.05; and the second catalyst is potassium carbonate.

[0018] Furthermore, the second mixed solvent is formed by mixing N-methylpyrrolidone and toluene in a volume ratio of 2:1; the total amount of resorcinol, 2,6-dichlorobenzonitrile and the second catalyst to the second mixed solvent has a solid-liquid ratio of 1g:0.9-1.5ml.

[0019] Furthermore, the crude product in step (2) is purified by pouring the crude product into cold water to precipitate, crushing and filtering; then soaking the obtained powder in acetone, standing for 8 hours, then filtering, and then soaking the obtained powder in a dilute hydrochloric acid solution for 8 hours, and then washing it with pure water by boiling for 3 to 5 times; then placing the washed powder in a vacuum oven and drying it for 12 hours; the dilute hydrochloric acid solution is obtained by mixing hydrochloric acid with a concentration of 36% and water in a volume ratio of 1:100.

[0020] Furthermore, the heating rate of the solution in steps (1), (2) and (3) is 5°C / min.

[0021] The invention also discloses a crystalline polyarylethernitrile composite film prepared by the preparation method.

[0022] The beneficial effects of the present invention are:

[0023] 1. The present invention first synthesizes high molecular weight polyarylether nitrile and low molecular weight polyarylether nitrile respectively; wherein, the high molecular weight polyarylether nitrile is copolymerized by hydroquinone (rigid structure) and resorcinol (flexible structure), and by adjusting the ratio of the two, the orderly arrangement of the chain segments can be achieved while ensuring the high molecular weight, thereby improving the crystallinity of the polyarylether nitrile; compared with some single bisphenol systems in the prior art, the high molecular weight polyarylether nitrile obtained in the present application has both excellent mechanical strength and processing properties. The low molecular weight polyarylether nitrile uses only resorcinol as the bisphenol monomer, and forms a branched structure by limiting chain growth. The obtained low molecular weight polyarylether nitrile is used as a crystallization nucleating agent for the high molecular weight matrix, which can reduce its crystallization activation energy, thereby promoting the crystallization of the high molecular weight polyarylether nitrile.

[0024] 2. When preparing the crystalline polyarylethernitrile composite film, the low molecular weight polyarylethernitrile is doped into the high molecular weight polyarylethernitrile. The branched structure of the low molecular weight polyarylethernitrile can be used as a nucleation site to reduce the activation energy of the orderly arrangement of the polymer chain (crystallization activation energy). The end group forms a hydrogen bond with the nitrile group of the high molecular weight polyarylethernitrile, inducing the molecular chains to stack in a specific direction, thereby improving the crystallinity of the composite film, thereby obtaining a crystalline polyarylethernitrile composite film with excellent performance.

[0025] 3. The composite film of the present invention is prepared by combining high molecular weight polyarylethernitrile and low molecular weight polyarylethernitrile. The rigid aromatic ring main chain of the high molecular weight polyarylethernitrile provides strength support, and the flexible ether bond of the low molecular weight polyarylethernitrile plasticizes the amorphous region, thereby improving the elongation at break of the composite film and achieving a synergistic improvement in strength and toughness. At the same time, the low molecular weight polyarylethernitrile forms a molecular-level interpenetrating network with the high molecular weight polyarylethernitrile matrix through the terminal active groups, which evenly disperses the external force to the crystalline region and the amorphous region, inhibits the crack propagation path, and further improves the film strength.

[0026] 4. The present invention uses low molecular weight polyarylethernitrile to induce crystallization of high molecular weight polyarylethernitrile matrix. The regular arrangement of nitrile groups in the crystallization region of the obtained composite film reduces the disordered oscillation of dipoles, thereby improving the constant of the obtained composite film and reducing the dielectric loss of the film. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 The DSC curves of the crystalline poly(arylene ether nitrile) composite films prepared in the examples and comparative examples are shown;

[0028] Figure 2 The TGA curves of the crystalline poly(arylene ether nitrile) composite films prepared in the examples and comparative examples;

[0029] Figure 3 The dielectric constant (a) and node loss (b) of the crystalline poly(arylene ether nitrile) composite films prepared in Examples 1 to 5 and Comparative Example 1;

[0030] Figure 4 The dielectric constant (a) and node loss (b) of the crystalline poly(arylene ether nitrile) composite films prepared in Examples 6 to 10 and Comparative Example 2;

[0031] Figure 5 These are polarized photographs of the crystalline poly(arylene ether nitrile) composite films prepared in Example 8 and Comparative Example 2. DETAILED DESCRIPTION

[0032] The specific implementation modes of the present invention are described in detail below with reference to the embodiments.

[0033] Example 1

[0034] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0035] Step 1: Preparation of high molecular weight crystallizable poly(arylether nitrile) (PEN)

[0036] (1) adding hydroquinone, resorcinol and 2,6-dichlorobenzonitrile as reactants into a three-necked flask equipped with a thermometer and a mechanical stirring device, and adding potassium carbonate as a catalyst to obtain a mixture powder; wherein the molar ratio of hydroquinone, resorcinol, 2,6-dichlorobenzonitrile and potassium carbonate is 8:2:10:13;

[0037] (2) adding a mixed solvent to a three-necked flask and stirring until completely dissolved to obtain a mixed solution A; the mixed solvent used is prepared by mixing N-methylpyrrolidone (NMP) and toluene in a volume ratio of 3:1; the solid-liquid ratio of the mixed powder to the mixed solvent is 1 g:1.5 ml;

[0038] (3) The temperature of the mixed solution A was raised to 186°C at a heating rate of 5°C / min and kept for reaction for 2 hours to obtain a crude product;

[0039] (4) The crude product is poured into cold water to precipitate, crushed, and filtered to obtain a light yellow powder; the powder is soaked in acetone, allowed to stand for 8 hours, and then filtered. The obtained powder is then soaked in a dilute hydrochloric acid solution (36% hydrochloric acid mixed with water in a volume ratio of 1:100) for 8 hours, and then boiled and washed with pure water for 4 times until the pH is neutral; the washed powder is placed in a vacuum oven and dried for 12 hours to obtain PEN powder.

[0040] Step 2: Preparation of low molecular weight RS polyarylethernitrile resin (PENRS)

[0041] (1) adding resorcinol and 2,6-dichlorobenzonitrile as reactants into a three-necked flask equipped with a thermometer and a mechanical stirring device, and adding potassium carbonate as a catalyst to obtain a mixture powder; wherein the molar ratio of resorcinol, 2,6-dichlorobenzonitrile and potassium carbonate is 1:1:1.05;

[0042] (2) adding a mixed solvent to a three-necked flask and stirring until completely dissolved to obtain a mixed solution B; the mixed solvent used is prepared by mixing N-methylpyrrolidone (NMP) and toluene in a volume ratio of 2:1; the solid-liquid ratio of the mixed powder to the mixed solvent is 1 g:1.5 ml;

[0043] (3) Raising the temperature of the mixed solution B to 190°C at a heating rate of 5°C / min and keeping the temperature for reaction for 2 hours to obtain a crude product;

[0044] (4) The crude product was poured into cold water to precipitate, crushed, and filtered to obtain a yellow powder; the powder was soaked in acetone, allowed to stand for 8 hours, and then filtered. The obtained powder was then soaked in a dilute hydrochloric acid solution (36% hydrochloric acid and water mixed in a volume ratio of 1:100) for 8 hours, and then boiled and washed with pure water for 4 times until the pH was neutral; the washed powder was placed in a vacuum oven and dried for 12 hours to obtain PENRS powder.

[0045] Step 3: Preparation of crystalline poly(arylene ether nitrile) composite film

[0046] (1) PEN powder and PENRS powder were mixed at a mass ratio of 50:1 to obtain a blended powder.

[0047] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0048] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the program is completed, the mixture is cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0049] Example 2

[0050] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0051] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0052] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0053] (1) PEN powder and PENRS powder were mixed at a mass ratio of 25:1 to obtain a blended powder.

[0054] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0055] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the program is completed, the mixture is cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0056] Example 3

[0057] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0058] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0059] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0060] (1) PEN powder and PENRS powder were mixed in a mass ratio of 50:3 to obtain a blended powder.

[0061] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0062] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the program is completed, the mixture is cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0063] Example 4

[0064] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0065] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0066] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0067] (1) PEN powder and PENRS powder were mixed in a mass ratio of 50:4 to obtain a blended powder.

[0068] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0069] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the program is completed, the mixture is cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0070] Example 5

[0071] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0072] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0073] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0074] (1) PEN powder and PENRS powder were mixed in a mass ratio of 10:1 to obtain a blended powder.

[0075] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0076] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the program is completed, the mixture is cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0077] Example 6

[0078] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0079] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0080] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0081] (1) PEN powder and PENRS powder were mixed at a mass ratio of 50:1 to obtain a blended powder.

[0082] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0083] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and the temperature is kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and the temperature is kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and the temperature is kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and the temperature is kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and the temperature is kept at 200°C for 2 hours; after the program is completed, the film is cooled to room temperature to obtain a preliminary film;

[0084] (4) The initial film product is heated to 280° C. within 1 hour, kept at this temperature for 2 hours, and then naturally cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0085] Example 7

[0086] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0087] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0088] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0089] (1) PEN powder and PENRS powder were mixed at a mass ratio of 25:1 to obtain a blended powder.

[0090] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0091] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and the temperature is kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and the temperature is kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and the temperature is kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and the temperature is kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and the temperature is kept at 200°C for 2 hours; after the program is completed, the film is cooled to room temperature to obtain a preliminary film;

[0092] (4) The initial film product is heated to 280° C. within 1 hour, kept at this temperature for 2 hours, and then naturally cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0093] Example 8

[0094] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0095] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0096] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0097] (1) PEN powder and PENRS powder were mixed in a mass ratio of 50:3 to obtain a blended powder.

[0098] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0099] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and the temperature is kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and the temperature is kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and the temperature is kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and the temperature is kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and the temperature is kept at 200°C for 2 hours; after the program is completed, the film is cooled to room temperature to obtain a preliminary film;

[0100] (4) The initial film product is heated to 280° C. within 1 hour, kept at this temperature for 2 hours, and then naturally cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0101] Example 9

[0102] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0103] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0104] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0105] (1) PEN powder and PENRS powder were mixed in a mass ratio of 50:4 to obtain a blended powder.

[0106] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0107] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and the temperature is kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and the temperature is kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and the temperature is kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and the temperature is kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and the temperature is kept at 200°C for 2 hours; after the program is completed, the film is cooled to room temperature to obtain a preliminary film;

[0108] (4) The initial film product is heated to 280° C. within 1 hour, kept at this temperature for 2 hours, and then naturally cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0109] Example 10

[0110] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0111] Step 1: A high molecular weight crystallizable poly(arylether nitrile) (PEN) and a low molecular weight RS poly(arylether nitrile) resin (PENRS) were prepared by the same method as in Example 1.

[0112] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0113] (1) PEN powder and PENRS powder were mixed in a mass ratio of 10:1 to obtain a blended powder.

[0114] (2) dissolving the blended powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the blended powder to N-methylpyrrolidone is 1:13;

[0115] (3) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and the temperature is kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and the temperature is kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and the temperature is kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and the temperature is kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and the temperature is kept at 200°C for 2 hours; after the program is completed, the film is cooled to room temperature to obtain a preliminary film;

[0116] (4) The initial film product is heated to 280° C. within 1 hour, kept at this temperature for 2 hours, and then naturally cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0117] Comparative Example 1

[0118] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0119] Step 1: A high molecular weight crystallizable poly(arylene ether nitrile) (PEN) was prepared by the same method as in Example 1.

[0120] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0121] (1) dissolving PEN powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of PEN powder to N-methylpyrrolidone is 1:13;

[0122] (2) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the program is completed, the mixture is cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0123] Comparative Example 2

[0124] A crystalline poly(arylene ether nitrile) composite film is prepared by the following steps:

[0125] Step 1: A high molecular weight crystallizable poly(arylene ether nitrile) (PEN) was prepared by the same method as in Example 1.

[0126] Step 2: Preparation of crystalline poly(arylether nitrile) composite film

[0127] (1) dissolving PEN powder in N-methylpyrrolidone (NMP) to obtain a mixed solution C; the volume ratio of the mixed powder to N-methylpyrrolidone is 1:13;

[0128] (2) The temperature of the mixed solution C is raised to 140°C at a heating rate of 5°C / min, and the mixture is kept warm and stirred for 4 hours to obtain a hot solution; the obtained hot solution is formed into a film by a casting method, and the heating process of the casting method is as follows: the temperature is raised from room temperature to 80°C within 10 minutes, and the temperature is kept at 80°C for 1 hour; then the temperature is raised to 100°C within 10 minutes, and the temperature is kept at 100°C for 1 hour; then the temperature is raised to 120°C within 10 minutes, and the temperature is kept at 120°C for 1 hour; then the temperature is raised to 160°C within 20 minutes, and the temperature is kept at 160°C for 2 hours; then the temperature is raised to 200°C within 20 minutes, and the temperature is kept at 200°C for 2 hours; after the program is completed, the film is cooled to room temperature to obtain a preliminary film;

[0129] (3) The initial film product is heated to 280° C. within 1 hour, kept at this temperature for 2 hours, and then naturally cooled to room temperature to obtain a crystalline poly(arylene ether nitrile) composite film.

[0130] Experimental example

[0131] The thermal properties of the crystalline poly(arylene ether nitrile) composite films prepared in the above-mentioned embodiments and comparative examples were tested by thermogravimetric analysis (TGA-Q50) and differential scanning calorimetry (DSC-Q100); the dielectric properties of the crystalline poly(arylene ether nitrile) composite films were tested by a precision LCR meter (TH 2819A).

[0132] The differential scanning calorimetry analysis of the crystalline poly(arylene ether nitrile) composite films prepared in the examples and comparative examples is as follows: Figure 1 The thermogravimetric analysis results are shown in Figure 2 As shown. Figure 1 and 2 It can be seen that the addition of low molecular weight RS poly(arylether nitrile) to the matrix has a significant effect on the T g The effect is not significant. A small amount of low molecular weight RS poly(arylether nitrile) can reduce the cold crystallization peak of the composite film, which makes it easier for the composite film to crystallize.

[0133] The dielectric properties analysis results of the crystalline poly(arylene ether nitrile) composite films prepared in Examples 1 to 5 and Comparative Example 1 are as follows: Figure 3 As shown, the dielectric properties analysis results of the crystalline poly(arylene ether nitrile) composite films prepared in Examples 6 to 10 and Comparative Example 2 are as follows: Figure 4 As shown. Figure 3 and 4 It can be seen that the addition of low molecular weight RS polyarylethernitrile can improve the dielectric constant of the composite film, which is more obvious after isothermal treatment. After isothermal treatment, the dielectric loss of the composite film is lower.

[0134] In order to more intuitively compare the performance of the crystalline poly(arylene ether nitrile) composite film in the embodiment and the comparative example, the thermodynamic properties and dielectric properties of the film are listed in Table 1.

[0135] Table 1 Thermodynamic and dielectric properties of the films

[0136] <![CDATA[T g / ℃]]> <![CDATA[T 5% / ℃]]> Dielectric constant (10KHz) Dielectric loss (10KHz) Example 1 174 503.8 3.90 0.0086 Example 2 173.9 493.5 4.09 0.0086 Example 3 173.6 489.2 4.53 0.012 Example 4 173.2 489.1 4.29 0.0149 Example 5 173 484.8 4.22 0.023 Example 6 176.5 510 3.940 0.0073 Example 7 176.7 502.3 4.716 0.0080 Example 8 178.2 496 4.374 0.011 Example 9 176.4 488.9 4.338 0.014 Example 10 176.2 486.8 3.945 0.015 Comparative Example 1 174.1 500.8 3.52 0.0083 Comparative Example 2 175.8 503.1 3.713 0.025

[0137] In addition, polarization analysis tests were performed on the crystalline poly(arylether nitrile) composite films prepared in Example 8 and Comparative Example 2. The results are as follows: Figure 5 As shown in the figure, it can be seen that the crystal quantity of Example 8 is larger than that of Comparative Example 2, and the crystal size is more perfect, indicating that the low molecular weight RS polyarylethernitrile can promote the crystallization of the matrix PEN.

[0138] Although the specific implementation of the present invention is described in detail in conjunction with the embodiments, it should not be understood as limiting the scope of protection of this patent. Within the scope described in the claims, various modifications and variations that can be made by those skilled in the art without creative work still fall within the scope of protection of this patent.

Claims

1. A method for preparing a crystalline poly(arylene ether nitrile) composite film, characterized in that: The following steps are involved: (1) Preparation of high molecular weight crystallizable poly(arylene ether nitrile): Putting hydroquinone, resorcinol, 2,6-dichlorobenzonitrile and the first catalyst into a reaction container, adding the first mixed solvent to dissolve, then heating the resulting solution to 180-190° C., keeping the temperature for reaction for 1.5-3 hours to obtain a crude product, and then purifying the crude product to obtain a high molecular weight crystallizable polyarylethernitrile; (2) Preparation of low molecular weight RS polyarylether nitrile resin Putting resorcinol, 2,6-dichlorobenzonitrile and a second catalyst into a reaction container, adding a second mixed solvent to dissolve, then heating the resulting solution to 185-195° C., keeping the temperature for reaction for 2-3 hours to obtain a crude product, and then purifying the crude product to obtain a low molecular weight RS polyarylethernitrile resin; (3) Preparation of crystalline poly(arylene ether nitrile) composite films A high molecular weight crystallizable polyarylethernitrile and a low molecular weight RS polyarylethernitrile resin are mixed in a mass ratio of 50:1-5, and then the mixture is dissolved in N-methylpyrrolidone, and the obtained solution is heated to 140°C to obtain a hot solution; then the obtained hot solution is formed into a film by a casting method, and the heating program of the casting film forming process is: from room temperature to 80°C within 10 minutes, and kept at 80°C for 1 hour; then heated to 100°C within 10 minutes, and kept at 100°C for 1 hour; then heated to 120°C within 10 minutes, and kept at 120°C for 1 hour; then heated to 160°C within 20 minutes, and kept at 160°C for 2 hours; then heated to 200°C within 20 minutes, and kept at 200°C for 2 hours; after the heating program is completed, it is cooled to room temperature to obtain a crystalline polyarylethernitrile composite film.

2. The preparation method according to claim 1, characterized in that: After the film is cast in step (3), a heat treatment is performed. The heat treatment method is as follows: the film cooled to room temperature after the heating program is completed is heated to 280°C within 1 hour, kept warm for 2 hours, and then naturally cooled to room temperature to obtain a crystalline polyarylethernitrile composite film.

3. The preparation method according to claim 1, characterized in that: The molar ratio of the hydroquinone, resorcinol, 2,6-dichlorobenzonitrile and the first catalyst is 8:2:10:13; and the first catalyst is potassium carbonate.

4. The preparation method according to claim 3, characterized in that: The first mixed solvent is formed by mixing N-methylpyrrolidone and toluene in a volume ratio of 3:1; the total amount of hydroquinone, resorcinol, 2,6-dichlorobenzonitrile and the first catalyst to the first mixed solvent has a solid-liquid ratio of 1g:0.9-1.5ml.

5. The preparation method according to claim 1, characterized in that: The purification method of the crude product in step (1) is as follows: pouring the crude product into cold water to precipitate, crushing and filtering; then soaking the obtained powder in acetone, standing for 8 hours, then filtering, and then soaking the obtained powder in a dilute hydrochloric acid solution for 8 hours, and then boiling and washing with pure water for 3 to 5 times; then placing the washed powder in a vacuum oven and drying it for 12 hours; the dilute hydrochloric acid solution is obtained by mixing hydrochloric acid with a concentration of 36% and water in a volume ratio of 1:

100.

6. The preparation method according to claim 1, characterized in that: The molar ratio of the resorcinol, 2,6-dichlorobenzonitrile and the second catalyst is 1:1:1.05; and the second catalyst is potassium carbonate.

7. The preparation method according to claim 6, characterized in that: The second mixed solvent is formed by mixing N-methylpyrrolidone and toluene in a volume ratio of 2:1; the total amount of resorcinol, 2,6-dichlorobenzonitrile and the second catalyst to the second mixed solvent has a solid-liquid ratio of 1g:0.9-1.5ml.

8. The preparation method according to claim 1, characterized in that: The purification method of the crude product in step (2) is as follows: pouring the crude product into cold water to precipitate, crushing and filtering; then soaking the obtained powder in acetone, standing for 8 hours, then filtering, and then soaking the obtained powder in a dilute hydrochloric acid solution for 8 hours, and then boiling and washing with pure water for 3 to 5 times; then placing the washed powder in a vacuum oven and drying it for 12 hours; the dilute hydrochloric acid solution is obtained by mixing hydrochloric acid with a concentration of 36% and water in a volume ratio of 1:

100.

9. The preparation method according to claim 1, characterized in that: The heating rate of the solution in steps (1), (2) and (3) is 5°C / min.

10. The crystalline poly(arylene ether nitrile) composite film obtained by the preparation method according to any one of claims 1 to 9.

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