An organic associating molecule / polyetherimide energy storage composite dielectric film and its preparation method and application

Abstract

An organic associating molecule / polyetherimide energy storage composite dielectric film and its preparation method and application, which belongs to energy storage dielectric materials and its preparation method and application. The purpose of the present invention is to solve the problems of poor insulation properties, high conductivity loss and low energy storage density of existing polyetherimide-based energy storage composite dielectrics. An organic associating molecule / polyetherimide energy storage composite dielectric film is composited by organic associating molecules and polyetherimide; the organic associating molecules are formed by non-covalent association of organic small molecules with electron-repelling properties and organic small molecules with electrophilic properties; the organic molecule associating filler has strong intermolecular forces and can form more delocalized structures, which not only enhances the electron capture effect, but also avoids charge accumulation through strong scattering effects. An organic associating molecule / polyetherimide energy storage composite dielectric film is used as an energy storage material for pulse capacitors or in pulse energy storage devices under electrothermal field coupling conditions.

Description

Technical Field

[0001] The present invention relates to energy storage dielectric materials and a preparation method and application thereof. Background Art

[0002] Currently, with the rapid expansion of high-end fields such as new energy vehicles, electromagnetic launches, and aerospace exploration, the demand for pulse capacitors has surged. These applications place extremely high demands on capacitors, requiring not only higher voltage resistance, low dielectric loss, and high power density, but also long-term energy storage stability and reliability. However, existing energy storage materials perform poorly in high electric fields, high temperatures, and complex electrothermal coupling environments, becoming a bottleneck limiting the widespread application of pulse capacitors.

[0003] Polyetherimide (PEI) has attracted attention as a potential material to replace traditional biaxially oriented polypropylene due to its excellent temperature resistance. However, its benzene ring structure easily promotes electron transport and reduces the energy storage efficiency of the material. To this end, researchers have proposed modification strategies including nanofiller doping, multilayer structure design and polymer blending, aiming to suppress carrier transport by forming localized states. However, these methods have limited improvement effects and are prone to accumulate space charges inside the dielectric, causing electric field distortion under complex electrothermal coupling conditions, further limiting performance improvements. Therefore, in order to develop dielectric materials with high electrical strength and excellent energy storage efficiency, it is urgent to start from the two aspects of reducing carrier accumulation and transport, and to collaboratively design new material structures to meet the use requirements of pulse capacitors under harsh conditions. Summary of the Invention

[0004] The purpose of the present invention is to solve the problems of poor insulation properties, high conductivity loss and low energy storage density of existing polyetherimide-based energy storage composite dielectrics, and to provide an organic associating molecule / polyetherimide energy storage composite dielectric film and its preparation method and application.

[0005] An organic associating molecule / polyetherimide energy storage composite dielectric film is composed of an organic associating molecule and polyetherimide; the organic associating molecule is formed by an organic small molecule with electron-repelling properties and an organic small molecule with electrophilic properties being associated through non-covalent bonds;

[0006] The electron-repelling organic small molecule is 4-(dimethylamino)phenylboronic acid;

[0007] The electrophilic organic small molecule is tetrafluorotetracyanoquinolinodimethane, 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] or 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester.

[0008] A method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film is specifically completed by the following steps:

[0009] 1. dissolving the electron-repelling organic small molecules and the electrophilic organic small molecules in an organic solvent, and then ultrasonically treating the organic small molecules for a period of time to obtain an associated molecular solution;

[0010] 2. dissolving polyetherimide into the associating molecule solution, and then performing vacuum defoaming treatment to obtain a bubble-free polyetherimide / associating molecule mixed solution;

[0011] 3. The bubble-free polyetherimide / associating molecule mixed solution is scraped on the substrate and then dried to obtain an organic associating molecule / polyetherimide energy storage composite medium film.

[0012] An organic associating molecule / polyetherimide energy storage composite dielectric film is used as an energy storage material for a pulse capacitor; the pulse capacitor is used in the field of electric-thermal field coupling of new energy vehicle inverters, electromagnetic emission pulse systems, or aerospace exploration energy storage systems.

[0013] An organic associating molecule / polyetherimide energy storage composite dielectric film is used in a pulse energy storage device under electrothermal field coupling conditions. The pulse energy storage device can achieve an energy storage density of 6.52 J / cm at 150°C, 660 kV / mm, and a charge and discharge efficiency of 91%. 3 .

[0014] Compared with the prior art, the present invention has the following beneficial effects:

[0015] 1. The present invention mixes organic small molecules with opposite electron affinities in different proportions to construct a complex (molecular association filler) interacting through non-covalent bonds, and incorporates it into polyetherimide (PEI) to prepare a composite dielectric; the electron-repelling filler (organic small molecule with electron-repelling properties) is selected from 4-(dimethylamino)phenylboronic acid (4-NB), and the electron-attracting filler (organic small molecule with electrophilic properties) is selected from tetrafluorotetracyanoquinolinodimethane (F4TCNQ), 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2, 1(3H)-dimethyl)]]bis[propylamine] (ITIC) or 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester (PCBM); molecularly associated fillers have strong intermolecular forces and can form more delocalized structures, which not only enhances the electron capture effect, but also avoids charge accumulation through strong scattering effects and reduces the free volume of the composite medium, ultimately effectively regulating the carrier transport behavior and reducing conductivity losses. The presence of molecularly associated fillers also forms an electric dipole layer at the electrode and interface, which plays a role in hindering electron injection. Results show that the prepared composite medium has an energy storage density of 6.52 J / cm at 150°C, 660 kV / mm, and a charge-discharge efficiency of 91%. 3 ;

[0016] Second, the organic associating molecule / polyetherimide energy storage composite dielectric film prepared by the present invention can form an electric dipole layer at the electrode and interface by utilizing the molecular associating filler, thereby changing the interfacial potential distribution and playing a role in hindering electron injection;

[0017] 3. The organic associating molecule / polyetherimide energy storage composite dielectric film prepared by the present invention can utilize the delocalized structural oscillation of the molecular associating filler to dissipate the energy of electrons, reduce the electron jump conduction distance, and hinder the long-distance transmission of electrons;

[0018] Fourth, the organic associating molecule / polyetherimide energy storage composite dielectric film prepared by the present invention can utilize the strong dipole-dipole interaction of the associating molecules composed of the organic small molecules with attractive electronic properties and the organic small molecules with repulsive electronic properties to enhance the dipole moment in the dielectric, thereby improving the relative dielectric constant of the dielectric;

[0019] Fifth, by introducing molecularly associated fillers, this invention enhances the intermolecular forces in the material, giving it strong impact resistance. This allows it to effectively withstand the high current shocks generated by pulse capacitors and prevent damage to the film material caused by electron migration due to high current shocks, thereby significantly improving the material's service reliability. Furthermore, this invention improves the short-term breakdown performance of the composite dielectric while reducing the introduction of deep traps. The low trap density solution also demonstrates promising application potential in the long-term durability of capacitor films. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 XRD patterns of organic associating molecules / polyetherimide energy storage composite dielectric films prepared in different embodiments;

[0021] Figure 2 Infrared spectra of organic associating molecules / polyetherimide energy storage composite dielectric films prepared in different embodiments;

[0022] Figure 3 1 is a graph showing the change in dielectric constant and dielectric loss of the composite dielectric film with frequency at 150°C. In the graph, (a) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 1 to 5; (b) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 6 to 10. (c) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester associating molecules;

[0023] Figure 4The Weibull distribution of the breakdown field strength of the composite dielectric film at 150°C; (a) in the figure is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 1 to 5; (b) in the figure is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 6 to 10; (c) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with indene-2,1(3H)-dimethylene)]]bis[propylamine] associating molecules; (c) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester associating molecules in Examples 11 to 15; (d) is a pure polyetherimide energy storage composite dielectric film and a polyetherimide energy storage composite dielectric film doped with tetrafluorotetracyanoquinolinodimethane obtained in Comparative Examples 1 to 2;

[0024] Figure 5 The intermolecular force simulation diagrams of the associated molecules composed of different types of electrophilic small molecules / electron repelling small molecules according to different ratios in Examples 1 to 15 are shown;

[0025] Figure 6 Free volume simulation diagram of the organic associating molecule / polyetherimide energy storage composite dielectric film prepared in Examples 1 to 15;

[0026] Figure 7 The surface electrostatic potential cloud diagram and potential statistics diagram of the associated molecules, in which (a) is the associated molecule of 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane; (b) is the associated molecule of 4-(dimethylamino)phenylboronic acid / 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1, 2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] association molecule; (c) is a 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester association molecule;

[0027] Figure 8The energy storage density diagram and energy storage efficiency diagram of the composite dielectric film at 150°C are shown in FIG. 1 ; (a) and (b) in the figure are organic associating molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 1 to 5; (c) and (d) are organic associating molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 6 to 10; :5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] association molecules doped with polyetherimide to obtain an organic association molecule / polyetherimide energy storage composite dielectric film; (e) and (f) are organic association molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester association molecules in Examples 11 to 15;

[0028] Figure 9 The energy storage density diagram and energy storage efficiency diagram of the pure polyetherimide energy storage dielectric film and the polyetherimide energy storage composite dielectric film doped with tetrafluorotetracyanoquinolinodimethane obtained in Comparative Examples 1 and 2 at 150°C are shown;

[0029] Figure 10 Figure 1 is a hopping conduction fitting diagram and a Schottky barrier fitting diagram of the composite dielectric film. In the figure, (a) and (b) are organic association molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane association molecules in Examples 1 to 5; (c) and (d) are organic association molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5, (e) and (f) are organic associating molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester associating molecules. DETAILED DESCRIPTION

[0030] Specific embodiment 1: This embodiment is an organic associating molecule / polyetherimide energy storage composite dielectric film, which is composed of an organic associating molecule and polyetherimide; the organic associating molecule is composed of an organic small molecule with electron-repelling properties and an organic small molecule with electrophilic properties that are associated through non-covalent bonds;

[0031] The electron-repelling organic small molecule is 4-(dimethylamino)phenylboronic acid;

[0032] The electrophilic organic small molecule is tetrafluorotetracyanoquinolinodimethane, 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] or 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester.

[0033] Specific embodiment 2: This embodiment differs from specific embodiment 1 in that the volume ratio of the organic associating molecule to the polyetherimide is 0.007:1. The other steps are the same as those of specific embodiment 1.

[0034] Specific embodiment 3: This embodiment differs from specific embodiment 1 or 2 in that the volume ratio of the electrophilic organic small molecule to the electron-repelling organic small molecule is 1:(0.3-3). Other steps are the same as specific embodiment 1 or 2.

[0035] Specific embodiment 4: This embodiment is a method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film, which is specifically completed by the following steps:

[0036] 1. dissolving the electron-repelling organic small molecules and the electrophilic organic small molecules in an organic solvent, and then ultrasonically treating the organic small molecules for a period of time to obtain an associated molecular solution;

[0037] 2. dissolving polyetherimide into the associating molecule solution, and then performing vacuum defoaming treatment to obtain a bubble-free polyetherimide / associating molecule mixed solution;

[0038] 3. The bubble-free polyetherimide / associating molecule mixed solution is scraped on the substrate and then dried to obtain an organic associating molecule / polyetherimide energy storage composite medium film.

[0039] Specific embodiment 5: This embodiment differs from specific embodiments 1 to 4 in that the organic solvent in step 1 is N-methylpyrrolidone, dimethylacetamide, or N,N-dimethylformamide; the volume ratio of the total mass of the electron-repelling organic small molecule and the electrophilic organic small molecule in step 1 to the organic solvent is (0.00105 g to 0.00126 g):1 mL; and the volume ratio of the total mass of the electron-repelling organic small molecule, the electrophilic organic small molecule, and the polyetherimide in step 2 to the organic solvent is (0.15 g to 0.18 g):1 mL. The other steps are the same as specific embodiments 1 to 4.

[0040] Specific embodiment 6: This embodiment differs from specific embodiments 1 to 5 in that: in step 1, the electron-repelling organic small molecules and the electrophilic organic small molecules are dissolved in the organic solvent at 60°C to 70°C and a stirring speed of 300 to 500 r / min; the ultrasonic treatment in step 1 is performed using a gradient ultrasonic dispersion combined with a gradient cooling technique. The specific method is as follows: first, the solution is ultrasonically dispersed at a power of 200 W and a temperature of 30°C for 30 minutes, then the power is increased to 400 W, the temperature is lowered to 25°C, and ultrasonic dispersion is carried out at a power of 400 W and a temperature of 25°C for 15 minutes. Finally, the power is increased to 500 W, the temperature is lowered to 20°C, and ultrasonic dispersion is carried out at a power of 500 W and a temperature of 20°C for 10 minutes. The other steps are the same as specific embodiments 1 to 5.

[0041] Specific embodiment 7: This embodiment differs from specific embodiments 1 to 6 in that: in step 2, polyetherimide is dissolved in the associating molecule solution at 60°C to 70°C and a stirring speed of 300 to 500 r / min; the vacuum defoaming method described in step 2 uses a gradient vacuum and gradient temperature treatment, specifically: first, standing at 500 mbar vacuum and 60°C for 5 to 15 minutes, then standing at 100 mbar vacuum and 65°C for 5 to 15 minutes, and finally standing at 10 mbar vacuum and 70°C for 5 to 15 minutes. The other steps are the same as specific embodiments 1 to 6.

[0042] Specific embodiment eight: This embodiment differs from specific embodiments one to seven in that the drying method described in step three is:

[0043] ① In an environment without natural light and with a relative humidity of 40%, keep warm at 70℃ for 4 hours and then at 120℃ for 2 hours;

[0044] ②In an environment without natural light and with a relative humidity of 30%, keep warm at 150℃ for 2 hours and then at 200℃ for 2 hours;

[0045] ③ In an environment without natural light and with a relative humidity of 20%, keep warm at 200°C for 4 hours in an argon atmosphere;

[0046] ④. Place the film in a nitrogen atmosphere and cool it to room temperature, and control the nitrogen flow along the coating direction;

[0047] The thickness of the organic associating molecule / polyetherimide energy storage composite medium film in step 3 is 3 μm to 15 μm. The other steps are the same as those in specific embodiments 1 to 7.

[0048] Specific Embodiment 9: This embodiment differs from Specific Embodiments 1 through 8 in that an organic associating molecule / polyetherimide energy storage composite dielectric film is used as the energy storage material for a pulse capacitor; this pulse capacitor is used in the field of electric-thermal field coupling in new energy vehicle inverters, electromagnetic emission pulse systems, or aerospace exploration energy storage systems. The remaining steps are the same as Specific Embodiments 1 through 8.

[0049] Specific embodiment 10: The difference between this embodiment and specific embodiments 1 to 9 is that an organic associating molecule / polyetherimide energy storage composite dielectric film is used for a pulse energy storage device under electrothermal field coupling conditions, and the pulse energy storage device can achieve an energy storage density of 6.52 J / cm at 150 ° C, 660 kV / mm, and a charge and discharge efficiency of 91%. 3 The other steps are the same as those in Specific Embodiments 1 to 9.

[0050] The following examples are used to verify the beneficial effects of the present invention:

[0051] Example 1: A method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film using 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules doped with polyetherimide is specifically completed by the following steps:

[0052] 1. Dissolving an electron-repelling organic small molecule and an electrophilic organic small molecule in N-methylpyrrolidone at 60°C and a stirring speed of 300 r / min, followed by ultrasonic treatment for a period of time to obtain a 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associated molecular solution (F4TCNQ / 4-NB associated molecular solution);

[0053] The electron-repelling organic small molecule described in step 1 is 4-(dimethylamino)phenylboronic acid;

[0054] The electrophilic organic small molecule described in step 1 is tetrafluorotetracyanoquinodimethane (F4TCNQ);

[0055] The volume ratio of tetrafluorotetracyanoquinolinodimethane to 4-(dimethylamino)phenylboronic acid described in step 1 is 1:1;

[0056] The volume ratio of the total mass of tetrafluorotetracyanoquinolinodimethane and 4-(dimethylamino)phenylboronic acid to N-methylpyrrolidone described in step 1 is 0.00126 g:1 mL;

[0057] 2. Under the conditions of 60℃ and stirring speed of 300r / min, PolyK company's model Ultem 1000% polyetherimide is dissolved in a 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecule solution, and then vacuum degassing is performed to obtain a bubble-free polyetherimide / associating molecule mixed solution;

[0058] The volume ratio of the total mass of the electron-repelling organic small molecule, the electrophilic organic small molecule and the polyetherimide described in step 2 to the organic solvent is 0.16 g:1 mL;

[0059] 3. Pour the bubble-free polyetherimide / associating molecule mixed solution evenly onto a clean, flat glass plate at 70°C. Raise the coating knife to a height of 15 μm and apply it horizontally at a speed of 5 cm / s. Then dry it to obtain a 10 μm thick, dense organic associating molecule / polyetherimide energy storage composite dielectric film (denoted as FN 1-1).

[0060] The ultrasonic treatment described in step 1 is carried out by gradient ultrasonic dispersion treatment combined with gradient cooling technology, and the specific method is: first, the solution is ultrasonically dispersed at a power of 200 W and a temperature of 30° C. for 30 minutes, then the power is increased to 400 W, the temperature is reduced to 25° C., and ultrasonic dispersion is carried out at a power of 400 W and a temperature of 25° C. for 15 minutes, and finally the power is increased to 500 W, the temperature is reduced to 20° C., and ultrasonic dispersion is carried out at a power of 500 W and a temperature of 20° C. for 10 minutes;

[0061] The vacuum defoaming treatment method described in step 2 is a gradient vacuum and gradient temperature treatment, specifically: first, stand at a vacuum degree of 500 mbar and 60°C for 15 minutes, then stand at a vacuum degree of 100 mbar and 65°C for 15 minutes, and finally stand at a vacuum degree of 10 mbar and 70°C for 15 minutes;

[0062] The drying method described in step 3 is:

[0063] ① In an environment without natural light and with a relative humidity of 40%, keep warm at 70℃ for 4 hours and then at 120℃ for 2 hours;

[0064] ②In an environment without natural light and with a relative humidity of 30%, keep warm at 150℃ for 2 hours and then at 200℃ for 2 hours;

[0065] ③ In an environment without natural light and with a relative humidity of 20%, keep warm at 200°C for 4 hours in an argon atmosphere;

[0066] ④. Place the film in a nitrogen atmosphere and cool it to room temperature, and control the nitrogen flow along the coating direction.

[0067] Example 2: This example differs from Example 1 in that the volume ratio of tetrafluorotetracyanoquinolinodimethane to 4-(dimethylamino)phenylboronic acid in Step 1 is 1:2. The resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated FN 1-2. All other steps and parameters are the same as in Example 1.

[0068] Example 3: This example differs from Example 1 in that the volume ratio of tetrafluorotetracyanoquinolinodimethane to 4-(dimethylamino)phenylboronic acid in Step 1 is 1:3. The resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated FN 1-3. All other steps and parameters are the same as in Example 1.

[0069] Example 4: This example differs from Example 1 in that the volume ratio of tetrafluorotetracyanoquinolinodimethane to 4-(dimethylamino)phenylboronic acid in Step 1 is 2:1. The resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated FN 2-1. All other steps and parameters are the same as in Example 1.

[0070] Example 5: This example differs from Example 1 in that the volume ratio of tetrafluorotetracyanoquinolinodimethane to 4-(dimethylamino)phenylboronic acid in Step 1 is 3:1. The resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated FN 3-1. All other steps and parameters are the same as in Example 1.

[0071] Example 6: A method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] associating molecules, specifically comprising the following steps:

[0072] 1. Dissolving an electron-repelling organic small molecule and an electrophilic organic small molecule in N-methylpyrrolidone at 60° C. and a stirring speed of 300 r / min, and then ultrasonicating for a period of time to obtain an associated molecule solution (ITIC / 4-NB associated molecule solution);

[0073] The electron-repelling organic small molecule described in step 1 is 4-(dimethylamino)phenylboronic acid;

[0074] The electrophilic organic small molecule described in step 1 is 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] (ITIC);

[0075] The volume ratio of 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] to 4-(dimethylamino)phenylboronic acid described in step 1 is 1:1;

[0076] The volume ratio of the total mass of 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] and 4-(dimethylamino)phenylboronic acid to N-methylpyrrolidone described in step 1 is 0.00126 g:1 mL;

[0077] 2. At 60℃ and stirring speed of 300r / min, PolyK company's model 1000% polyetherimide is dissolved in a 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecule solution, and then vacuum degassing is performed to obtain a bubble-free polyetherimide / associating molecule mixed solution;

[0078] The volume ratio of the total mass of the electron-repelling organic small molecule, the electrophilic organic small molecule and the polyetherimide described in step 2 to the organic solvent is 0.16 g:1 mL;

[0079] 3. Pour the bubble-free polyetherimide / associating molecule mixed solution evenly onto a clean, flat glass plate at 70°C, raise the coating knife to a height of 15 μm, and apply it horizontally at a speed of 5 cm / s. Then dry it to obtain a 10 μm thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film (denoted as IN 1-1).

[0080] The ultrasonic treatment described in step 1 is carried out by gradient ultrasonic dispersion treatment combined with gradient cooling technology, and the specific method is: first, the solution is ultrasonically dispersed at a power of 200 W and a temperature of 30° C. for 30 minutes, then the power is increased to 400 W, the temperature is reduced to 25° C., and ultrasonic dispersion is carried out at a power of 400 W and a temperature of 25° C. for 15 minutes, and finally the power is increased to 500 W, the temperature is reduced to 20° C., and ultrasonic dispersion is carried out at a power of 500 W and a temperature of 20° C. for 10 minutes;

[0081] The vacuum defoaming treatment method described in step 2 is a gradient vacuum and gradient temperature treatment, specifically: first, stand at a vacuum degree of 500 mbar and 60°C for 15 minutes, then stand at a vacuum degree of 100 mbar and 65°C for 15 minutes, and finally stand at a vacuum degree of 10 mbar and 70°C for 15 minutes;

[0082] The drying method described in step 3 is:

[0083] ① In an environment without natural light and with a relative humidity of 40%, keep warm at 70℃ for 4 hours and then at 120℃ for 2 hours;

[0084] ②In an environment without natural light and with a relative humidity of 30%, keep warm at 150℃ for 2 hours and then at 200℃ for 2 hours;

[0085] ③ In an environment without natural light and with a relative humidity of 20%, keep warm at 200°C for 4 hours in an argon atmosphere;

[0086] ④. Place the film in a nitrogen atmosphere and cool it to room temperature, and control the nitrogen flow along the coating direction.

[0087] Example 7: This example differs from Example 6 in that the volume ratio of 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] to 4-(dimethylamino)phenylboronic acid in Step 1 is 1:2; the prepared 10 μm thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated IN 1-2. Other steps and parameters are the same as in Example 1.

[0088] Example 8: This example differs from Example 6 in that the volume ratio of 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] to 4-(dimethylamino)phenylboronic acid in Step 1 is 1:3; the prepared 10 μm thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated IN 1-3. Other steps and parameters are the same as in Example 1.

[0089] Example 9: This example differs from Example 6 in that the volume ratio of 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] to 4-(dimethylamino)phenylboronic acid in Step 1 is 2:1; the prepared 10 μm thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated IN 2-1. Other steps and parameters are the same as in Example 1.

[0090] Example 10: This example differs from Example 6 in that the volume ratio of 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] to 4-(dimethylamino)phenylboronic acid in Step 1 is 3:1; the prepared 10 μm thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated IN 3-1. Other steps and parameters are the same as in Example 1.

[0091] Example 11: A method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film using 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester associating molecules doped with polyetherimide is specifically completed in the following steps:

[0092] 1. Dissolving an electron-repelling organic small molecule and an electrophilic organic small molecule in N-methylpyrrolidone at 60°C and a stirring speed of 300 r / min, and then ultrasonicating for a period of time to obtain an associated molecule solution (PCBM / 4-NB associated molecule solution);

[0093] The electron-repelling organic small molecule described in step 1 is 4-(dimethylamino)phenylboronic acid;

[0094] The electrophilic organic small molecule described in step 1 is 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester (PCBM);

[0095] The volume ratio of 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester to 4-(dimethylamino)phenylboronic acid described in step 1 is 1:1;

[0096] The volume ratio of the total mass of 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester and 4-(dimethylamino)phenylboronic acid to N-methylpyrrolidone described in step 1 is 0.00126 g:1 mL;

[0097] 2. Under the conditions of 60℃ and stirring speed of 300r / min, PolyK company's model Ultem 1000% polyetherimide is dissolved in a 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecule solution, and then vacuum degassing is performed to obtain a bubble-free polyetherimide / associating molecule mixed solution;

[0098] The volume ratio of the total mass of the electron-repelling organic small molecule, the electrophilic organic small molecule and the polyetherimide described in step 2 to the organic solvent is 0.16 g:1 mL;

[0099] 3. Pour the bubble-free polyetherimide / associating molecule mixed solution evenly onto a clean, flat glass plate at 70°C. Raise the coating knife to a height of 15 μm and apply it horizontally at a speed of 5 cm / s. Then dry it to obtain a 10 μm thick, dense organic associating molecule / polyetherimide energy storage composite dielectric film (denoted as PN 1-1).

[0100] The ultrasonic treatment described in step 1 is carried out by gradient ultrasonic dispersion treatment combined with gradient cooling technology, and the specific method is: first, the solution is ultrasonically dispersed at a power of 200 W and a temperature of 30° C. for 30 minutes, then the power is increased to 400 W, the temperature is reduced to 25° C., and ultrasonic dispersion is carried out at a power of 400 W and a temperature of 25° C. for 15 minutes, and finally the power is increased to 500 W, the temperature is reduced to 20° C., and ultrasonic dispersion is carried out at a power of 500 W and a temperature of 20° C. for 10 minutes;

[0101] The vacuum defoaming treatment method described in step 2 is a gradient vacuum and gradient temperature treatment, specifically: first, stand at a vacuum degree of 500 mbar and 60°C for 15 minutes, then stand at a vacuum degree of 100 mbar and 65°C for 15 minutes, and finally stand at a vacuum degree of 10 mbar and 70°C for 15 minutes;

[0102] The drying method described in step 3 is:

[0103] ① In an environment without natural light and with a relative humidity of 40%, keep warm at 70℃ for 4 hours and then at 120℃ for 2 hours;

[0104] ②In an environment without natural light and with a relative humidity of 30%, keep warm at 150℃ for 2 hours and then at 200℃ for 2 hours;

[0105] ③ In an environment without natural light and with a relative humidity of 20%, keep warm at 200°C for 4 hours in an argon atmosphere;

[0106] ④. Place the film in a nitrogen atmosphere and cool it to room temperature, and control the nitrogen flow along the coating direction.

[0107] Example 12: This example differs from Example 11 in that the volume ratio of 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester to 4-(dimethylamino)phenylboronic acid in Step 1 is 1:2; the resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated PN1-2. All other steps and parameters are the same as in Example 1.

[0108] Example 13: This example differs from Example 11 in that the volume ratio of 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester to 4-(dimethylamino)phenylboronic acid in Step 1 is 1:3; the resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated PN1-3. All other steps and parameters are the same as in Example 1.

[0109] Example 14: This example differs from Example 11 in that the volume ratio of 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester to 4-(dimethylamino)phenylboronic acid in Step 1 is 2:1. The resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated PN2-1. All other steps and parameters are the same as in Example 1.

[0110] Example 15: This example differs from Example 11 in that the volume ratio of 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester to 4-(dimethylamino)phenylboronic acid in Step 1 is 3:1; the resulting 10 μm-thick, densely structured organic associating molecule / polyetherimide energy storage composite dielectric film is designated PN3-1. All other steps and parameters are the same as in Example 1.

[0111] Comparative Example 1: Preparation of a pure polyetherimide energy storage dielectric film (PEI dielectric film), specifically completed by the following steps:

[0112] 1. At 60℃ and stirring speed of 300r / min, 1000% polyetherimide was completely dissolved in N-methylpyrrolidone, and then vacuum degassing was performed to obtain a bubble-free PEI solution;

[0113] The volume ratio of polyetherimide to N-methylpyrrolidone in step 1 is 0.16 g:1 mL;

[0114] 2. Pour the bubble-free PEI solution evenly onto a clean, flat glass plate, raise the coating knife to a height of 15 μm, apply it horizontally at a speed of 5 cm / s, and then dry it to form a 10 μm thick, densely structured PEI dielectric film (denoted as PEI);

[0115] The vacuum degassing method described in step 1 is: the vacuum degassing method adopts gradient vacuum and gradient temperature treatment, specifically: first, stand at a vacuum degree of 500 mbar and 60°C for 15 minutes, then stand at a vacuum degree of 100 mbar and 65°C for 15 minutes, and finally stand at a vacuum degree of 10 mbar and 70°C for 15 minutes;

[0116] The drying method described in step 2 is:

[0117] ① In an environment without natural light and with a relative humidity of 40%, keep warm at 70℃ for 4 hours and then at 120℃ for 2 hours;

[0118] ②In an environment without natural light and with a relative humidity of 30%, keep warm at 150℃ for 2 hours and then at 200℃ for 2 hours;

[0119] ③ In an environment without natural light and with a relative humidity of 20%, keep warm at 200°C for 4 hours in an argon atmosphere;

[0120] ④. Place the film in a nitrogen atmosphere and cool it to room temperature, and control the nitrogen flow along the coating direction.

[0121] Comparative Example 2: Preparation of a polyetherimide energy storage composite dielectric film doped with tetrafluorotetracyanoquinolinodimethane (F4TCNQ / PEI composite dielectric film), specifically completed by the following steps:

[0122] 1. Under the conditions of 60℃ and stirring speed of 300r / min, the PolyK company's model Ultem 1000% polyetherimide and tetrafluorotetracyanoquinodimethane with a high electron affinity were completely dissolved in N-methylpyrrolidone, and then vacuum degassing was performed to obtain a bubble-free F4TCNQ / PEI mixed solution;

[0123] In step 1, the volume ratio of tetrafluorotetracyanoquinolinodimethane to polyetherimide is 0.006:1;

[0124] The volume ratio of the total mass of polyetherimide and tetrafluorotetracyanoquinolinodimethane to N-methylpyrrolidone in step 1 is 0.16 g:1 mL;

[0125] 2. Pour the bubble-free F4TCNQ / PEI mixed solution evenly on a clean flat glass plate, raise the coating knife to a height of 15 μm, scrape horizontally at a speed of 5 cm / s, and then dry it to form a 10 μm thick and dense F4TCNQ / PEI composite dielectric film (denoted as F 0.6 );

[0126] The vacuum degassing method described in step 1 is: the vacuum degassing method adopts gradient vacuum and gradient temperature treatment, specifically: first, stand at a vacuum degree of 500 mbar and 60°C for 15 minutes, then stand at a vacuum degree of 100 mbar and 65°C for 15 minutes, and finally stand at a vacuum degree of 10 mbar and 70°C for 15 minutes;

[0127] The drying method described in step 2 is:

[0128] ① In an environment without natural light and with a relative humidity of 40%, keep warm at 70℃ for 4 hours and then at 120℃ for 2 hours;

[0129] ②In an environment without natural light and with a relative humidity of 30%, keep warm at 150℃ for 2 hours and then at 200℃ for 2 hours;

[0130] ③ In an environment without natural light and with a relative humidity of 20%, keep warm at 200°C for 4 hours in an argon atmosphere;

[0131] ④. Place the film in a nitrogen atmosphere and cool it to room temperature, and control the nitrogen flow along the coating direction.

[0132] Figure 1 XRD patterns of organic associating molecules / polyetherimide energy storage composite dielectric films prepared in different embodiments;

[0133] Depend on Figure 1 It can be seen that for the F4TCNQ and 4-NB co-doped composite dielectric, the XRD peak shifts slightly to the left with increasing 4-NB doping content, attributed to the reduction of PEI chain stacking by 4-NB. However, for the ITIC and 4-NB co-doped composite dielectrics and the PCBM and 4-NB co-doped composite dielectrics, the peak does not shift to the left. This may be due to the smaller molecular weight of F4TCNQ and its smaller electrostatic influence area, which is unable to resist the changes in molecular chain segments caused by 4-NB. In contrast, the larger molecular weights of ITIC and PCBM form a more stable association structure with 4-NB, which reduces the influence of 4-NB on molecular chain segments.

[0134] Figure 2 Infrared spectra of organic associating molecules / polyetherimide energy storage composite dielectric films prepared in different embodiments;

[0135] Depend on Figure 2The composite medium contains characteristic peaks such as the C=O stretching vibration peak of the imide ring, the CN stretching vibration peak of the imide ring, and the COC stretching vibration peak, but does not exhibit the characteristic peaks of the filler. This is mainly due to the low filler content, which is masked by the strong absorption peak of PEI, and the strong interaction between molecular association and filler, which causes the filler characteristic peaks to change.

[0136] Figure 3 1 is a graph showing the change in dielectric constant and dielectric loss of the composite dielectric film with frequency at 150°C. In the graph, (a) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 1 to 5; (b) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 6 to 10. (c) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester associating molecules;

[0137] Depend on Figure 3The relative dielectric constants of the F4TCNQ / 4-NB molecularly associated filler co-doped composites are superior to those of pure PEI. This increase in dielectric constant with increasing F4TCNQ content is attributed to the strong polarity of F4TCNQ. The relative dielectric constants of FN 2-1 and FN 3-1 reach 3.61 and 3.74, respectively, at 10 Hz, exceeding those of composites doped with the same amount of F4TCNQ or 4-NB alone. This is likely due to the interaction between the associated molecules and the PEI molecular segments, increasing the dipole moment within the dielectric and thus enhancing polarizability. Furthermore, both F4TCNQ and 4-NB have aromatic ring structures that can interact with the aromatic rings in PEI, thereby altering the dielectric constant of the PEI composite. The relative dielectric constant of the ITIC / 4-NB molecular associative filler co-doped composite dielectrics also increases with increasing electron-attracting ITIC molecule content. This can be attributed to the strong dipole-dipole interaction between ITIC and 4-NB, which enhances the overall polarity of the composite dielectric. Furthermore, the associating molecules influence the stacking of the dielectric molecular chains, further increasing the relative dielectric constant. The effect of PCBM / 4-NB molecular associative fillers on the relative dielectric constant of the composite dielectrics differs from that of the other two types. When the PCBM content is high, the relative dielectric constant of the composite dielectric increases due to the strong polarization of its fullerene moiety and the hollow structure of PCBM, which forms a large number of interfaces with PEI. However, due to the hollow structure of PCBM, its interaction with 4-NB leads to a more complex effect on the molecular chains of the PEI composite dielectric. Consequently, the relative dielectric constant decreases with increasing proportion of the more polar PCBM.

[0138] All three types of composite dielectrics doped with molecularly associated fillers exhibit excellent dielectric loss characteristics, remaining within 0.01 in the low-frequency range. The figure also shows that when the PCBM content in the composite dielectric is high, the dielectric loss increases slightly. This is primarily due to the spherical fullerene structure of PCBM, which easily forms interfaces and defects within the dielectric, leading to a slight increase in dielectric loss. F4TCNQ and ITIC, on the other hand, have nearly planar molecular structures, resulting in better compatibility with PEI. The difference in dielectric loss among the three types of composite dielectrics widens further at high frequencies. This is primarily due to the increased polarization hysteresis of polarized charges at defects, which leads to increased losses.

[0139] Figure 4The Weibull distribution of the breakdown field strength of the composite dielectric film at 150°C; (a) in the figure is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 1 to 5; (b) in the figure is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 6 to 10; (c) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with indene-2,1(3H)-dimethylene)]]bis[propylamine] associating molecules; (c) is an organic associating molecule / polyetherimide energy storage composite dielectric film obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester associating molecules in Examples 11 to 15; (d) is a pure polyetherimide energy storage composite dielectric film and a polyetherimide energy storage composite dielectric film doped with tetrafluorotetracyanoquinolinodimethane obtained in Comparative Examples 1 to 2;

[0140] Depend on Figure 4 It can be seen that when the F4TCNQ to 4-NB doping ratio is 1:1, the breakdown field strength of the composite dielectric is significantly improved to 671.0 kV / mm. When the F4TCNQ to 4-NB doping ratio is 1:3, the breakdown field strength of the composite dielectric reaches 660.2 kV / mm. The improvement effect is less pronounced at other ratios. This is likely due to the strong interaction between the fillers at the 1:1 and 1:3 ratios. The associative fillers with strong coercivity can withstand the impact of high-energy electrons, and the electrostatic potential distribution between the fillers changes, forming a delocalized structure between the positive and negative electrostatic potential groups, which enables electron capture and scattering, reducing electron energy without causing charge accumulation. At other ratios, the interaction between the fillers is weak, and the fillers can only play their own capture and scattering roles, failing to achieve functional synergy.

[0141] When ITIC / 4-NB associative fillers are introduced into PEI, the breakdown field strength of the composite medium can be increased to 704.1kV / mm when the ratio of ITIC to 4-NB is 1:2. The difference in the improvement ability at different ratios may be due to the difference in the interaction force between the fillers. When PCBM / 4-NB associative fillers are introduced into PEI, the breakdown field strength of the composite medium can be increased to 657.4kV / mm when the ratio of PCBM to 4-NB is 1:2. The optimal breakdown field strength of the polyetherimide composite medium doped with associative molecular fillers is higher than the breakdown field strength of the pure PEI film, and is also higher than that of the F4TCNQ single-doped F4TCNQ with a larger electron affinity. 0.6 The film exhibited excellent breakdown properties. A comprehensive comparison of the characteristic breakdown field strengths of different types of associative fillers and at varying content ratios revealed that ITIC / 4-NB fillers possessed the strongest ability to enhance the breakdown of composite dielectrics. This is likely due to ITIC's longer chain segments, which possess multiple electron-attracting sites. When co-doped with 4-NB, this allows for the formation of more delocalized structures, enhancing electron capture and scattering. However, this advantage was not observed in PCBM / 4-NB.

[0142] Figure 5 The intermolecular force simulation diagrams of the associated molecules composed of different types of electrophilic small molecules / electron repelling small molecules according to different ratios in Examples 1 to 15 are shown;

[0143] Depend on Figure 5 It can be seen that the interaction energy of the F4TCNQ / 4-NB molecularly associated filler reaches its maximum, -246.19 kcal / mol, at a filler ratio of 1:1, and reaches its minimum, -199.09 kcal / mol, at a filler ratio of 3:1. The breakdown field strength of the corresponding composite medium is highest when the filler interaction energy is maximum, and lowest when the interaction energy is minimum. However, at content ratios of 1:2, 1:3, and 2:1, the breakdown field strength of the corresponding medium does not increase with increasing filler interaction energy. Greater interaction energy in the ITIC / 4-NB molecularly associated filler is associated with greater breakdown field strength, except at ratios of 2:1 and 1:3. The breakdown field strength of the PCBM / 4-NB molecularly associated filler-doped PEI composite medium also does not increase with increasing intermolecular forces. Therefore, the breakdown field strength of the composite medium is not solely dependent on intermolecular forces within the filler.

[0144] Figure 6 Free volume simulation diagram of the organic associating molecule / polyetherimide energy storage composite dielectric film prepared in Examples 1 to 15;

[0145] Depend on Figure 6It can be seen that when doped with ITIC / 4-NB fillers, the free volume of the composite medium is small, all below 23.5%. This is primarily due to the strong interaction between ITIC and 4-NB, which allows for a stable association structure and reduces interchain porosity. The ITIC-4-NB complex has a large volume and limited segmental motion, thus restricting the motion of the PEI molecular chains. The low interaction energy between F4TCNQ and 4-NB, and between PCBM and 4-NB, leads to an unstable molecular association structure and weakens the constraint on the PEI molecular segments, thereby increasing the free volume of the composite medium. Furthermore, the F4TCNQ-4-NB complex has a low molecular weight and is easily embedded between molecular chains, which in turn increases porosity. The fullerene cage structure of PCBM also resists close packing, resulting in a larger free volume in the composite medium. A larger free volume increases the chances of electrons accelerating in free space, accumulating energy, and ultimately leading to dielectric breakdown.

[0146] Figure 7 The surface electrostatic potential cloud diagram and potential statistics diagram of the associated molecules, in which (a) is the associated molecule of 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane; (b) is the associated molecule of 4-(dimethylamino)phenylboronic acid / 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1, 2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] association molecule; (c) is a 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester association molecule;

[0147] Depend on Figure 7 It can be seen that the ITIC / 4-NB associative filler has more regions with large electrostatic potential differences, that is, more delocalized space, while PCBM / 4-NB and F4TCNQ / 4-NB have relatively few. This demonstrates that ITIC / 4-NB effectively captures and scatters charge carriers, thereby reducing conductivity losses. Furthermore, the delocalized structure captures electrons, causing them to oscillate within the structure, dissipating their energy. Even with long hopping distances, the electron energy is relatively low, minimizing the impact on conductivity. These phenomena indicate that the conductive current is not limited to hopping conduction mechanisms. This may also be because hopping conduction ignores interfacial effects, and the longer molecular chains of ITIC allow for a larger interfacial area with PEI.

[0148] Figure 8The energy storage density diagram and energy storage efficiency diagram of the composite dielectric film at 150°C are shown in FIG. 1 ; (a) and (b) in the figure are organic associating molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 1 to 5; (c) and (d) are organic associating molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane associating molecules in Examples 6 to 10; :5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] association molecules doped with polyetherimide to obtain an organic association molecule / polyetherimide energy storage composite dielectric film; (e) and (f) are organic association molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester association molecules in Examples 11 to 15;

[0149] Depend on Figure 8 It can be seen that in the PEI composite medium doped with F4TCNQ / 4-NB associated molecules, when the energy storage efficiency is not less than 90%, the energy storage density of FN 1-1 can reach 5.50 J / cm 3 , the corresponding polarization field strength is 600kV / mm, which is mainly attributed to its good breakdown performance, which increases the maximum polarization electric field. The polarization electric field of FN 1-3 at an energy storage efficiency of 90% is 580kV / mm, and the energy storage density reaches 4.62J / cm 3 The polarization electric field of FN 2-1 is only 540kV / mm when the energy storage efficiency is 91%, but the energy storage density exceeds that of FN 2-1 and can reach 4.70J / cm 3 This is mainly because the relative dielectric constant of FN 2-1 is greater than that of FN 1-3, and its polarization ability is stronger, so it can achieve higher energy storage performance even at lower electric fields. The energy storage performance of the ITIC / 4-NB associated molecule doped PEI composite medium can reach an energy storage density of 6.52 J / cm when the content ratio of ITIC and 4-NB is 1:2. 3 , and the energy storage efficiency remains at 91%, the corresponding polarization electric field is 660kV / mm, and the energy storage density is increased by 307.5% relative to PEI. The improvement in energy storage performance of the PCBM / 4-NB associating molecules on the PEI composite medium is slightly worse than that of F4TCNQ / 4-NB and ITIC / 4-NB. When the PCBM and 4-NB content ratio is 1:1, the energy storage density can reach 5.21J / cm 3, and the energy storage efficiency remains at 94.4%, corresponding to a polarization electric field of 580kV / mm.

[0150] Figure 9 The energy storage density diagram and energy storage efficiency diagram of the pure polyetherimide energy storage dielectric film and the polyetherimide energy storage composite dielectric film doped with tetrafluorotetracyanoquinolinodimethane obtained in Comparative Examples 1 and 2 at 150°C are shown;

[0151] Depend on Figure 9 It can be seen that the energy storage density of the F4TCNQ / 4-NB associated molecules doped PEI composite medium is increased by 225.6% relative to PEI, the energy storage density of the ITIC / 4-NB associated molecules doped PEI composite medium is increased by 307.5% relative to PEI, and the energy storage density of the PCBM / 4-NB associated molecules doped PEI composite medium is increased by 208.2% relative to PEI, and the energy storage efficiency is also better than PEI. The energy storage density of the PEI composite medium with single F4TCNQ doping can reach 4.86J / cm 3， But it is still not as good as the improvement effect of molecular associated fillers.

[0152] Figure 10 Figure 1 is a hopping conduction fitting diagram and a Schottky barrier fitting diagram of the composite dielectric film. In the figure, (a) and (b) are organic association molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / tetrafluorotetracyanoquinolinodimethane association molecules in Examples 1 to 5; (c) and (d) are organic association molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5, (e) and (f) are organic associating molecules / polyetherimide energy storage composite dielectric films obtained by doping polyetherimide with 4-(dimethylamino)phenylboronic acid / 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester associating molecules.

[0153] Depend on Figure 10It can be seen that the hopping distances of the composite dielectrics are all lower than those of PEI, indicating that the shorter electron hopping distance reduces conductivity losses, thus exhibiting better insulation properties. However, a detailed analysis revealed that the hopping distance of the composite dielectric doped with F4TCNQ / 4-NB filler reached a minimum of 1.29 nm at a doping ratio of 1:3. However, the composite dielectric with the lowest conductance current occurs at a doping ratio of 1:1, which is inconsistent with its larger hopping distance. The composite dielectric doped with IN / 4-NB filler exhibits a lower conductance current than the other two types, but similarly does not show a corresponding advantage in hopping distance. Analysis of the Schottky barrier fitting data for the composite dielectrics shows that all composite dielectrics have low intercepts. The PEI composite dielectric doped with ITIC / 4-NB molecularly associated filler exhibits a smaller intercept than the other two types, demonstrating a higher Schottky barrier and effectively hindering carrier injection. This may be because the associated molecules composed of electron-attracting and electron-repelling fillers have a significant dipole moment, which can form an electric dipole layer at the interface between the electrode and the dielectric, thereby changing the interfacial potential distribution. ITIC has a longer molecular chain, which can form more interfaces and, in turn, a stronger electric dipole layer. As shown in the figure, the Schottky barrier of the PCBM / 4-NB molecularly associated filler-doped PEI composite dielectric is between that of the ITIC / 4-NB and F4TCNQ / 4-NB-doped composite dielectrics, which is consistent with the above hypothesis. Overall analysis shows that the regulation of the conductivity loss of the composite dielectric by molecularly associated fillers is not only affected by internal hopping transport, but also by interfacial injection, which plays a key role.

[0154] In summary, the organic associating molecule / polyetherimide energy storage composite dielectric film prepared in the present invention has high high-temperature breakdown field strength, good polarization performance, good energy storage density and relatively stable high energy storage efficiency.

[0155] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Anyone familiar with this technology can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention should be based on the definition of the claims.

Claims

1. An organic associating molecule / polyetherimide energy storage composite dielectric film, characterized in that The organic associating molecule / polyetherimide energy storage composite medium film is composed of organic associating molecules and polyetherimide; the organic associating molecules are composed of organic small molecules with electron-repelling properties and organic small molecules with electrophilic properties that are associated through non-covalent bonds; The electron-repelling organic small molecule is 4-(dimethylamino)phenylboronic acid; The electrophilic organic small molecule is tetrafluorotetracyanoquinolinodimethane, 2,2'-[[[6,6,12,12-tetrakis(4-hexylphenyl)-6,12-dihydrodithio[2,3-D:2',3'-D']-S-indolol[1,2-B:5,6-B']dithiophene-2,8-diyl]bis[methylene(3-oxo-1H-indene-2,1(3H)-dimethylene)]]bis[propylamine] or 2ALPHA-phenyl-1,2(2ALPHA)-homo[5,6]fullerene-C60-LH-2ALPHA-butyric acid methyl ester; The volume ratio of the electrophilic organic small molecules to the electron-repelling organic small molecules is 1:1 or 1:

3.

2. The organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 1, characterized in that The volume ratio of the organic associating molecule to the polyetherimide is 0.007:

1.

3. The method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 1, characterized in that The preparation method is specifically completed according to the following steps:

1. dissolving the electron-repelling organic small molecules and the electrophilic organic small molecules in an organic solvent, and then ultrasonically treating the organic small molecules for a period of time to obtain an associated molecular solution; 2. dissolving polyetherimide into the associating molecule solution, and then performing vacuum defoaming treatment to obtain a bubble-free polyetherimide / associating molecule mixed solution; 3. The bubble-free polyetherimide / associating molecule mixed solution is scraped on the substrate and then dried to obtain an organic associating molecule / polyetherimide energy storage composite medium film.

4. The method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 3, characterized in that The organic solvent described in step one is N-methylpyrrolidone, dimethylacetamide or N,N-dimethylformamide; the volume ratio of the total mass of the electron-repelling organic small molecules and the electrophilic organic small molecules described in step one to the organic solvent is (0.00105g~0.00126g):1mL; the volume ratio of the total mass of the electron-repelling organic small molecules, the electrophilic organic small molecules and the polyetherimide described in step two to the organic solvent is (0.15g~0.18g):1mL.

5. The method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 3, characterized in that In step 1, under the conditions of 60° C. to 70° C. and a stirring speed of 300 r / min to 500 r / min, the electron-repelling organic small molecules and the electrophilic organic small molecules are dissolved in an organic solvent; the ultrasonic treatment described in step 1 is carried out by using a gradient ultrasonic dispersion treatment combined with a gradient cooling technology, and the specific method is: first, the solution is ultrasonically dispersed for 30 minutes at a power of 200 W and a temperature of 30° C., then the power is increased to 400 W, the temperature is reduced to 25° C., and ultrasonic dispersion is carried out for 15 minutes at a power of 400 W and a temperature of 25° C., and finally the power is increased to 500 W, the temperature is reduced to 20° C., and ultrasonic dispersion is carried out for 10 minutes at a power of 500 W and a temperature of 20° C.

6. The method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 3, characterized in that In step 2, polyetherimide is dissolved in the associating molecule solution at 60°C to 70°C and a stirring speed of 300r / min to 500r / min; the vacuum defoaming treatment method described in step 2 adopts gradient vacuum and gradient temperature treatment, specifically: first, let it stand for 5min to 15min in a vacuum environment of 500mbar and 60°C, then let it stand for 5min to 15min in a vacuum environment of 100mbar and 65°C, and finally let it stand for 5min to 15min in a vacuum environment of 10mbar and 70°C.

7. The method for preparing an organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 3, characterized in that The drying method described in step 3 is: ① In an environment without natural light and with a relative humidity of 40%, keep warm at 70℃ for 4 hours and then at 120℃ for 2 hours; ② In an environment without natural light and with a relative humidity of 30%, keep the temperature at 150°C for 2 hours and then at 200°C for 2 hours; ③ In an environment without natural light and with a relative humidity of 20%, keep warm at 200°C for 4 hours in an argon atmosphere; ④. Place the film in a nitrogen atmosphere and cool it to room temperature, and control the nitrogen flow along the coating direction; The thickness of the organic associating molecule / polyetherimide energy storage composite medium film described in step three is 3 μm to 15 μm.

8. The use of an organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 1, characterized in that An organic associating molecule / polyetherimide energy storage composite dielectric film is used as an energy storage material for a pulse capacitor; the pulse capacitor is used in the field of electric-thermal field coupling of new energy vehicle inverters, electromagnetic emission pulse systems, or aerospace exploration energy storage systems.

9. The use of an organic associating molecule / polyetherimide energy storage composite dielectric film according to claim 1, characterized in that An organic associating molecule / polyetherimide energy storage composite dielectric film is used in a pulse energy storage device under electrothermal field coupling conditions. The pulse energy storage device can achieve an energy storage density of 6.52 J / cm at 150°C, 660 kV / mm, and a charge and discharge efficiency of 91%. 3 .

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