A macromolecular dielectric enhancer, its preparation method and application

Abstract

The present application provides a kind of macromolecular dielectric enhancer and its preparation method and application. Especially in the application of preparation polypropylene capacitor film. Including: with diisocyanate compound and alkoxysilane as raw material preparation dielectric enhancer step;R1, R2 and R4 are selected from C 1‑8 Alkyl, C 5‑8 Cycloalkyl, C 6‑8 Aromatic group and C 1‑4 Alkoxy;R3 is C 1‑4 Alkyl;R' is C 2‑20 Olefin, alkane, alcohol, ether, ketone, aldehyde or ester, or C 5‑20 Cycloalkane or aromatic group;And, the step of the obtained dielectric enhancer and ethylene reaction to obtain macromolecular dielectric enhancer. The polypropylene prepared by the method is very suitable for thin film capacitor, lithium battery diaphragm and other related products requiring high dielectric constant and lower dielectric loss, which can significantly increase the capacity of capacitor.

Description

TECHNICAL FIELD

[0001] The present application relates to the chemical industry field, and in particular, the present application relates to a macromolecular dielectric enhancer, a preparation method and application thereof. BACKGROUND

[0002] In the prior art, a common method for improving the dielectric constant of polypropylene is to compound polypropylene with inorganic particles having a high dielectric constant to achieve complementary advantages of both. However, the addition of inorganic materials not only increases the defects of polypropylene, but also increases the dielectric loss of the polypropylene composite, and the breakdown strength of the capacitor film made therefrom is significantly reduced. Moreover, the inhomogeneous dispersion of inorganic materials makes the film processing process more difficult. Therefore, some researchers use polar organic substances to prepare a composite material with polypropylene to improve the dielectric constant of the capacitor film medium.

[0003] For example, CN202010199051.7 uses polyvinylidene fluoride-hexafluoropropylene as a raw material to prepare a polyvinylidene fluoride-hexafluoropropylene / polypropylene composite material by melt blending. The polyvinylidene fluoride-hexafluoropropylene and the polypropylene substrate in the composite material have good compatibility and dispersion. A 5-30 micron thin film made by further hot pressing or co-extrusion has the advantages of high dielectric constant and good processing performance.

[0004] CN201310708192.7 uses isotactic polypropylene, low-density polyethylene, sodium borate, methyltriacetoxysilane, sodium silicate, ethylenediaminetetraacetic acid, and sodium glycocholate to prepare a composite material as a raw material for a composite plastic metallized film for capacitors, which solves the problems of low dielectric constant, poor heat resistance, poor film-forming property, and low mechanical strength of general thin film capacitors.

[0005] In the above prior art, the addition of inorganic materials or organic materials can improve the dielectric constant, but significantly increases the dielectric loss of the polypropylene composite, and the breakdown strength of the capacitor film made therefrom is significantly reduced. Moreover, the inhomogeneous dispersion of inorganic materials makes the film processing process more difficult. SUMMARY

[0006] One object of the present application is to provide a preparation method of a macromolecular dielectric enhancer.

[0007] Another object of the present application is to provide a macromolecular dielectric enhancer.

[0008] Still another object of the present application is to provide a preparation method of high dielectric constant polypropylene.

[0009] Still another object of the present application is to provide a high dielectric constant polypropylene.

[0010] Another object of the present invention is to provide the use of the high dielectric constant polypropylene.

[0011] To achieve the above objectives, in one aspect, the present invention provides a method for preparing a macromolecular dielectric enhancer, wherein the method includes:

[0012] The steps for preparing dielectric enhancers using diisocyanate compounds of formula (II) and alkoxysilanes of formula (III) as raw materials;

[0013]

[0014] R1, R2, and R4 may be the same or different, and each is independently selected from one of the following: alkyl groups having 1-8 carbon atoms, cycloalkyl groups having 5-8 carbon atoms, aromatic groups having 6-8 carbon atoms, and alkoxy groups having 1-4 carbon atoms; R3 is an alkyl group having 1-4 carbon atoms.

[0015] R' is an alkene, alkane, alcohol, ether, ketone, aldehyde or ester group with 2-20 carbon atoms, or a cycloalkane or aromatic group with 5-20 carbon atoms;

[0016] as well as,

[0017] The step of reacting the obtained dielectric enhancer with ethylene to obtain the macromolecular dielectric enhancer;

[0018] Based on 100 parts by mass of diisocyanate compounds, the amount of alkoxysilane used in the reaction is 60-95 parts; the amount of ethylene used is to maintain a reaction pressure of 20-30 MPa.

[0019] According to some specific embodiments of the present invention, the diisocyanate compound is selected from one or more of dicyclohexylmethane-4,4'-diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and methylcyclohexane diisocyanate; the alkoxysilane is selected from one of dicyclopentyldimethoxysilane, phenyltriethoxysilane and diphenyldimethoxysilane.

[0020] According to some specific embodiments of the present invention, the diisocyanate compound is hexamethylene diisocyanate.

[0021] According to some specific embodiments of the present invention, the alkoxysilane is dicyclopentyldimethoxysilane.

[0022] According to some specific embodiments of the present invention, the method includes preparing a dielectric enhancer using diisocyanate compounds and alkoxysilanes as raw materials at 65-85°C, and then reacting the obtained dielectric enhancer with ethylene at 85-110°C and a pressure of 20-30 MPa for 2-5 hours to obtain the macromolecular dielectric enhancer.

[0023] According to some specific embodiments of the present invention, the diisocyanate compound and the alkoxysilane are reacted in the presence of initiator a to obtain a dielectric enhancer; the amount of initiator a is 0.2-0.5 parts per 100 parts by mass of the diisocyanate compound.

[0024] According to some specific embodiments of the present invention, the diisocyanate compound and the alkoxysilane are reacted in the presence of a solvent to obtain a dielectric enhancer; the amount of solvent used is 73-126 parts per 100 parts by mass of the diisocyanate compound.

[0025] According to some specific embodiments of the present invention, the step of preparing the dielectric enhancer includes: mixing a diisocyanate compound, a solvent, and an initiator a under an inert gas atmosphere, then adding alkoxysilane dropwise at 65-85°C at a dropping rate of 6-9% silane / min, and then reacting for 30-45 min to obtain the dielectric enhancer.

[0026] According to some specific embodiments of the present invention, the step of preparing the dielectric enhancer includes: mixing a diisocyanate compound, a solvent, and an initiator a at 55-70°C under an inert gas atmosphere, then heating to 75-90°C and stirring at 110-280 rpm for 20-40 min, adding alkoxysilane dropwise at 65-85°C, and then stirring the reaction at 90-120 rpm for 30-45 min to obtain the dielectric enhancer.

[0027] According to some specific embodiments of the present invention, the initiator a is an organic peroxide.

[0028] According to some specific embodiments of the present invention, the initiator a is selected from one or more of diacetyl peroxide, diisobutyryl peroxide, cumene hydroperoxide and benzoyl peroxide, or a mixture thereof.

[0029] According to some specific embodiments of the present invention, the initiator a is diacetyl peroxide.

[0030] According to some specific embodiments of the present invention, the solvent is a polyol.

[0031] According to some specific embodiments of the present invention, the polyol is selected from one or more of pentaerythritol, ethylene glycol, glycerol, 1,4-butanediol and 1,6-hexanediol, or a mixture thereof.

[0032] According to some specific embodiments of the present invention, the polyol is ethylene glycol.

[0033] According to some specific embodiments of the present invention, the inert gas atmosphere during the preparation of the dielectric enhancer is achieved by purging the reactor with inert gas 2-3 times.

[0034] According to some specific embodiments of the present invention, the step of preparing the dielectric enhancer includes:

[0035] Taking 100 parts by mass of diisocyanate compound, firstly, the reactor is purged with inert gas 2-3 times. Under an inert gas atmosphere, 100 parts of diisocyanate compound are weighed into the reactor. After heating the reactor to 55-70℃, 73-126 parts of polyol and 0.2-0.5 parts of initiator a are added. The temperature is then further increased to 75-90℃ and stirred at 110-280 rpm for 20-40 min. At a reactor temperature of 65-85℃, 60-95 parts of alkoxysilane are added dropwise at a rate of 6-9 w% silane / min. The mixture is stirred at 90-120 rpm for 30-45 min until the reaction is complete, thus obtaining the dielectric enhancer.

[0036] According to some specific embodiments of the present invention, the dielectric enhancer and ethylene are reacted in the presence of a nickel-based complexing catalyst and an alkylaluminoxane co-catalyst to obtain the macromolecular dielectric enhancer; based on 1 part by mass of the nickel-based complexing catalyst, the amount of the alkylaluminoxane co-catalyst is 55-80 parts, and the amount of the dielectric enhancer is 2-4 parts.

[0037] According to some specific embodiments of the present invention, the step of preparing the macromolecular dielectric enhancer includes mixing a nickel-based complex, an alkylaluminoxane cocatalyst, and a dielectric enhancer with a solvent under an inert gas atmosphere, introducing ethylene, and reacting to obtain the macromolecular dielectric enhancer.

[0038] According to some specific embodiments of the present invention, the step of preparing the macromolecular dielectric enhancer includes adding an alkylaluminoxane co-catalyst dropwise to a solvent under an inert gas atmosphere at 85-110°C and a stirring speed of 400-800 rpm, stirring for 15-30 min, adding a nickel-based complex catalyst and a dielectric enhancer, introducing ethylene to carry out the reaction, and then obtaining the macromolecular dielectric enhancer by centrifugation and drying.

[0039] According to some specific embodiments of the present invention, the nickel-based complexing catalyst is selected from one of (1-naphthyl)[8-(diphenylphosphino)quinoline]nickel chloride, trans-phenyl bromide (di(triphenylphosphine))nickel, and 2,5-dicarboxypyrrole nickel dibromide; the alkylaluminoxane co-catalyst is selected from one of methylaluminoxane (MAO) and ethylaluminoxane (EAO).

[0040] According to some specific embodiments of the present invention, the nickel-based complexing catalyst is (1-naphthyl)[8-(diphenylphosphino)quinoline]nickel.

[0041] According to some specific embodiments of the present invention, the alkylaluminoxane cocatalyst is methylaluminoxane.

[0042] According to some specific embodiments of the present invention, in the step of preparing the macromolecular dielectric enhancer, the dielectric enhancer and ethylene are reacted in a solvent in the presence of a nickel-based complexing catalyst and an alkylaluminoxane co-catalyst to obtain the macromolecular dielectric enhancer; the amount of solvent used is 400-600 parts by mass, with 1 part by mass of the nickel-based complexing catalyst.

[0043] According to some specific embodiments of the present invention, the inert gas atmosphere during the preparation of macromolecular dielectric enhancers is achieved by purging the reactor with inert gas 2-3 times.

[0044] According to some specific embodiments of the present invention, the solvent used in preparing the macromolecular dielectric enhancer is selected from toluene, ethylbenzene, xylene, dichloroethane, and cyclohexanone.

[0045] According to some specific embodiments of the present invention, the solvent used in preparing the macromolecular dielectric enhancer is toluene.

[0046] According to some specific embodiments of the present invention, the step of preparing the macromolecular dielectric enhancer includes:

[0047] Taking one part by mass of nickel-based complex catalyst, firstly, inert gas is purged into the high-pressure reactor 2-3 times, and after heating to 85-110℃, 400-600 parts of solvent are added. Under uniform stirring at 400-800 rpm, 55-80 parts of alkylaluminoxane co-catalyst are gradually added dropwise. Stirring is continued for 15-30 min under inert gas protection. Then, one part of nickel-based complex catalyst and 2-4 parts of dielectric enhancer are added, and ethylene is introduced. The pressure is maintained at 20-30 MPa for 2.0-5.0 h. After the reaction is completed, the macromolecular dielectric enhancer is obtained by centrifugation, drying, and processing.

[0048] On the other hand, the present invention also provides a macromolecular dielectric enhancer, wherein the macromolecular dielectric enhancer is prepared according to the preparation method described in any one of the preceding claims of the present invention.

[0049] According to some specific embodiments of the present invention, the macromolecular dielectric enhancer is as shown in formula (I):

[0050]

[0051] R' is an alkene, alkane, alcohol, ether, ketone, aldehyde or ester group with 2-20 carbon atoms, or a cycloalkane or aromatic group with 5-20 carbon atoms;

[0052] R1 and R2 may be the same or different, and each is independently selected from one of the following: alkyl groups having 1-8 carbon atoms, cycloalkyl groups having 5-8 carbon atoms, aromatic groups having 6-8 carbon atoms, and alkoxy groups having 1-4 carbon atoms;

[0053] n is 6-22.

[0054] In another aspect, the present invention also provides a method for preparing polypropylene with high dielectric constant, wherein the method comprises preparing the polypropylene with high dielectric constant by means of a polymerization reaction using the macromolecular dielectric enhancer described in any one of the present invention and propylene as raw materials.

[0055] According to some specific embodiments of the present invention, the method includes preparing the high dielectric constant polypropylene by polymerization reaction using the macromolecular dielectric enhancer and propylene as raw materials in the presence of a supported Ziegler-Natta catalyst and initiator b; the macromolecular dielectric enhancer is 8-15 parts by mass of 1 part by mass of supported Ziegler-Natta catalyst, the initiator b is 3-6 parts by mass of initiator b, and the amount of propylene used is to maintain a reaction pressure of 15-25 MPa.

[0056] According to some specific embodiments of the present invention, the polymerization reaction of the macromolecular dielectric enhancer and propylene is carried out at a temperature of 65-90°C, a pressure of 15-25 MPa, and a reaction time of 1.5-3 h.

[0057] According to some specific embodiments of the present invention, the method includes mixing a supported Ziegler-Natta catalyst, initiator b and a macromolecular dielectric enhancer under an inert gas atmosphere, introducing propylene and hydrogen, and carrying out a polymerization reaction for 1.5-3 hours at a temperature of 65-90°C and a pressure of 15-25 MPa to obtain the high dielectric constant polypropylene.

[0058] According to some specific embodiments of the present invention, the inert gas atmosphere in the preparation of high dielectric constant polypropylene is achieved by heating the reactor and evacuating it, followed by inert gas replacement 2-4 times.

[0059] According to some specific embodiments of the present invention, the method for preparing high dielectric constant polypropylene includes:

[0060] Using 1 part by mass of the supported Ziegler-Natta catalyst, the high-pressure reactor is heated and evacuated to remove air and water. The reactor is then purged with inert gas 2-4 times. Then, 1 part of the supported Ziegler-Natta solid catalyst, 8-15 parts of macromolecular dielectric enhancer, and 3-6 parts of initiator b are added. Propylene and a small amount of hydrogen are then introduced, and the pressure is maintained at 15-25 MPa and the reactor temperature at 65-90℃ to start polymerization. After reacting for 1.5-3 hours, the unreacted gas is discharged to obtain polypropylene powder with a high dielectric constant.

[0061] According to some specific embodiments of the present invention, the method further includes the step of fully mixing the obtained high dielectric constant polypropylene with an antioxidant composite additive and then extruding and granulating it to obtain high dielectric constant polypropylene resin granules, wherein the mass of the antioxidant composite additive is 0.12-0.58 parts based on 100 parts of the mass of the high dielectric constant polypropylene.

[0062] According to some specific embodiments of the present invention, the extrusion granulation is performed using a screw kneader.

[0063] According to some specific embodiments of the present invention, the screw kneader is selected from a single-screw extruder, a twin-screw extruder, and a multi-screw extruder with 3-5 screws, preferably a twin-screw extruder.

[0064] According to some specific embodiments of the present invention, the antioxidant complex additive comprises an acid remover, a primary antioxidant, and a secondary antioxidant; with the total mass of the antioxidant complex additive being 100%.

[0065] According to some specific embodiments of the present invention, the acid-removing agent is selected from one or a combination of two of metal stearates and hydrotalcite; the main antioxidant is selected from 2,6-di-tert-butyl-p-cresol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-S-triazine-2,4,6-(1H,3H,5H)trione, octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-trimethyl- The co-antioxidant is selected from one or more combinations of 2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene and 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane; the co-antioxidant is selected from one or more combinations of dilauryl thiodipropionate, dioctadecyl thiodipropionate, di(tetradecyl) thiodipropionate, trinonylphenyl phosphite, di(octadecyl)pentaerythritol diphosphite, tris(2,4-tert-butylphenyl) phosphite and di(2,4-di-tert-butylphenyl)pentaerythritol diphosphite.

[0066] According to some specific embodiments of the present invention, the acid remover is selected from one or a combination of two of zinc stearate and calcium stearate.

[0067] According to some specific embodiments of the present invention, the antioxidant composite additive is a product of Beijing Jiyi Holdings Group Co., Ltd.

[0068] The components of the supported Ziegler-Natta catalysts described in this invention are generally known to those skilled in the art. Typically, the Ziegler-Natta main catalyst comprises a titanium compound and an optional internal electron donor. An internal electron donor refers to a compound that is part of the solid Ziegler-Natta main catalyst. The titanium compound and the optional internal electron donor are preferably supported on a solid magnesium compound support.

[0069] According to some specific embodiments of the present invention, the supported Ziegler-Natta catalyst comprises a main catalyst and an organometallic co-catalyst; the main catalyst is a combination of one or more catalysts selected from ethyl benzoate, phthalic acid monoester or diester, monoether, diether or succinate as internal electron donors, with MgCl2 as support and TiCl4 as active center; the organometallic co-catalyst is composed of alkyl aluminum compounds.

[0070] According to some specific embodiments of the present invention, the alkylaluminum compound is selected from one or more combinations of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, diethylaluminum chloride, and ethylaluminum dichloride.

[0071] According to some specific embodiments of the present invention, the alkylaluminum compound is triethylaluminum.

[0072] According to some specific embodiments of the present invention, the internal electron donor is diisobutyl phthalate.

[0073] According to some specific embodiments of the present invention, the content of active transition metal element (Ti) in the main catalyst of the present invention is 1.85-3.56 wt% based on the total mass of the main catalyst being 100%, and the organometallic co-catalyst alkyl aluminum is added in a ratio of Al / Ti (molar) = 50-80.

[0074] According to some specific embodiments of the present invention, the supported Ziegler-Natta catalyst is a product of Yingkou Xiangyang Catalyst Co., Ltd.

[0075] According to some specific embodiments of the present invention, the initiator b is an organic peroxide.

[0076] According to some specific embodiments of the present invention, the initiator b is selected from one of tert-butyl hydroperoxide, dicumyl peroxide, cumyl hydroperoxide, benzoyl peroxide, and di-tert-butyl peroxide.

[0077] According to some specific embodiments of the present invention, the initiator b is tert-butyl hydroperoxide.

[0078] According to some specific embodiments of the present invention, the method further includes a step of prepolymerizing propylene and a macromolecular dielectric enhancer at 10-45°C, and then carrying out a polymerization reaction to obtain the high dielectric constant polypropylene.

[0079] According to some specific embodiments of the present invention, the amount of hydrogen added is well known to those skilled in the art, and the amount of hydrogen added is within the conventional addition range for propylene polymerization in the prior art. The present invention does not impose any particular limitation.

[0080] The high-pressure reactor for preparing high dielectric constant polypropylene described in this invention can be a loop reactor or a batch reactor, preferably a batch reactor.

[0081] The polymerization method for preparing high dielectric constant polypropylene described in this invention can utilize known liquid-phase bulk polymerization or gas-phase polymerization, with liquid-phase bulk polymerization being preferred. This method operates in a liquid phase or via a mixed liquid-gas technique. These methods are well known to those skilled in the art.

[0082] The polymerization reactions described in this invention are carried out in an oxygen-free, anhydrous, and inert gas environment. The inert gas is nitrogen or a gas of a group 0 element in the periodic table, excluding radon, with nitrogen being preferred.

[0083] In another aspect, the present invention also provides high dielectric constant polypropylene prepared by the method for preparing high dielectric constant polypropylene according to any one of the present invention.

[0084] According to some specific embodiments of the present invention, the dielectric constant of the high dielectric constant polypropylene is greater than 2.

[0085] According to some specific embodiments of the present invention, the dielectric constant of the high dielectric constant polypropylene is 2.5-2.8.

[0086] According to some specific embodiments of the present invention, the dielectric loss of the high dielectric constant polypropylene is less than 3tgδ×10. 4 .

[0087] According to some specific embodiments of the present invention, the dielectric loss of the high dielectric constant polypropylene is less than 2.6tgδ×10. 4 .

[0088] According to some specific embodiments of the present invention, the dielectric loss of the high dielectric constant polypropylene is 2.20-2.55 tgδ×10 4 .

[0089] In another aspect, the present invention also provides the application of the high dielectric constant polypropylene in the preparation of thin-film capacitors or lithium battery separators.

[0090] It is understood that, without contradiction, the various specific embodiments of the present invention can be arbitrarily combined with each other.

[0091] In summary, this invention provides a macromolecular dielectric enhancer, its preparation method, and its application. The technical solution of this invention has the following advantages:

[0092] This invention first synthesizes a dielectric enhancer with strong polar groups using alkoxysilanes and diisocyanates in a polyol environment; secondly, in the presence of a nickel-based complexing catalyst, a macromolecular dielectric enhancer with free radical reactivity is prepared from the reactive monomer ethylene and the dielectric enhancer; finally, in the presence of peroxides, the macromolecular dielectric enhancer is added to a polypropylene polymerization reactor for further reaction, thus preparing polypropylene with a high dielectric constant through the dual action of free radical polymerization and grafting.

[0093] The polypropylene prepared by this method has a high dielectric constant and low dielectric loss, making it very suitable for use in products such as film capacitors and lithium battery separators that require high dielectric constant and low dielectric loss, and can significantly increase the capacitance of capacitors.

[0094] The high dielectric constant polypropylene prepared by this invention significantly increases the dielectric constant of the polypropylene film without significantly increasing the dielectric loss of the polypropylene film, thereby avoiding a reduction in the breakdown strength of the polypropylene film in the service environment. Detailed Implementation

[0095] The following detailed embodiments illustrate the implementation process and beneficial effects of the present invention, aiming to help readers better understand the essence and characteristics of the present invention, and are not intended to limit the scope of implementation of this case.

[0096] Example 1

[0097] (1) Preparation of dielectric enhancer:

[0098] First, the reactor was purged twice with nitrogen. Under a nitrogen atmosphere, 100g of hexamethylene diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 55°C, and 73g of ethylene glycol and 0.2g of diacetyl peroxide were added. The temperature was then raised to 75°C and stirred at 110 rpm for 20 min. At a reactor temperature of 65°C, 60g of dicyclopentyldimethoxysilane was added dropwise at a rate of 6w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 90 rpm for 30 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0099] (2) Preparation of macromolecular dielectric enhancers:

[0100] First, nitrogen was purged twice in a jacketed 10L high-pressure reactor. After heating to 85℃, 400g of toluene was added. Then, 55g of methylaluminoxane co-catalyst was added dropwise under uniform stirring at 400rpm. Stirring was continued for 15min under nitrogen protection. Then, 1g of nickel chloride (1-naphthyl)[8-(diphenylphosphino)quinoline] and 2g of the dielectric enhancer were added, and ethylene was introduced. The pressure was maintained at 20MPa and the reaction was carried out for 2.0h. After the reaction was completed, the polymer dielectric enhancer was obtained by centrifugation, drying, and extraction.

[0101] (3) Preparation of polypropylene with high dielectric constant:

[0102] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged twice with nitrogen. 1g of MgCl2-supported Ziegler-Natta solid catalyst (purchased from Yingkou Xiangyang Catalyst Co., Ltd., composition: TiCl4, triethylaluminum, diisobutyl phthalate), 8g of the macromolecular dielectric enhancer, and 3g of tert-butyl hydrogen peroxide were then introduced. Propylene and a small amount of hydrogen were then introduced, maintaining the pressure at 15MPa and the reactor temperature at 65℃ to begin polymerization. After 1.5 hours of reaction, unreacted gases were discharged to obtain high dielectric constant polypropylene powder.

[0103] (4) 1000g of the high dielectric constant polypropylene powder and 1.2g of antioxidant composite additive (purchased from Beijing Jiyi Holdings Group Co., Ltd.) are thoroughly mixed and then added to a twin-screw extruder for extrusion granulation to obtain high dielectric constant polypropylene resin granules.

[0104] After preparing thin film samples from high dielectric constant polypropylene resin granules according to standard methods, dielectric tests were performed.

[0105] Example 2

[0106] (1) Preparation of dielectric enhancer:

[0107] First, the reactor was purged with nitrogen three times. Under a nitrogen atmosphere, 100g of hexamethylene diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 70°C, and 126g of ethylene glycol and 0.5g of diacetyl peroxide were added. The temperature was then raised to 90°C and stirred at 280 rpm for 40 min. At a reactor temperature of 85°C, 95g of dicyclopentyldimethoxysilane was added dropwise at a rate of 9w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 120 rpm for 45 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0108] (2) Preparation of macromolecular dielectric enhancers:

[0109] First, nitrogen was purged three times in a jacketed 10L high-pressure reactor. After heating to 110℃, 600g of toluene was added. 80g of methylaluminoxane co-catalyst was added dropwise under uniform stirring at 800rpm. Stirring continued for 30min under nitrogen protection. Then, 1g of nickel chloride (1-naphthyl)[8-(diphenylphosphino)quinoline] and 4g of the dielectric enhancer were added, and ethylene was introduced. The reaction was carried out at 30MPa for 5.0h. After the reaction was completed, the polymer dielectric enhancer was obtained by centrifugation, drying, and extraction.

[0110] (3) Preparation of polypropylene with high dielectric constant:

[0111] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged with nitrogen three times. Next, 1g of MgCl2-supported Ziegler-Natta solid catalyst (purchased from Yingkou Xiangyang Catalyst Co., Ltd., composed of TiCl4, triethylaluminum, and diisobutyl phthalate), 15g of the macromolecular dielectric enhancer, and 6g of tert-butyl hydrogen peroxide were added. Propylene and a small amount of hydrogen were then introduced, maintaining a pressure of 25MPa and a reactor temperature of 90℃ to initiate polymerization. After 3 hours of reaction, unreacted gases were discharged to obtain high dielectric constant polypropylene powder.

[0112] (4) 1000g of the high dielectric constant polypropylene powder and 5.8g of antioxidant composite additive (purchased from Beijing Jiyi Holdings Group Co., Ltd.) are thoroughly mixed and then added to a twin-screw extruder for extrusion granulation to obtain high dielectric constant polypropylene resin granules.

[0113] After preparing thin film samples from high dielectric constant polypropylene resin granules according to standard methods, dielectric tests were performed.

[0114] Example 3

[0115] (1) Preparation of dielectric enhancer:

[0116] First, the reactor was purged with nitrogen three times. Under a nitrogen atmosphere, 100g of hexamethylene diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 60°C, and 100g of ethylene glycol and 0.3g of diacetyl peroxide were added. The temperature was then raised to 80°C and stirred at 210 rpm for 30 min. At a reactor temperature of 70°C, 75g of dicyclopentyldimethoxysilane was added dropwise at a rate of 7w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 100 rpm for 40 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0117] (2) Preparation of macromolecular dielectric enhancers:

[0118] First, nitrogen was purged three times in a jacketed 10L high-pressure reactor. After heating to 90℃, 500g of toluene was added. 70g of methylaluminoxane co-catalyst was gradually added dropwise under uniform stirring at 650rpm. Stirring continued for 20min under nitrogen protection. Then, 1g of (1-naphthyl)[8-(diphenylphosphino)quinoline]nickel chloride and 3g of the dielectric enhancer were added, and ethylene was introduced. The reaction was carried out at 25MPa for 3.5h. After the reaction was completed, the polymer dielectric enhancer was obtained by centrifugation, drying, and extraction.

[0119] (3) Preparation of polypropylene with high dielectric constant:

[0120] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged with nitrogen three times. Next, 1g of MgCl2-supported Ziegler-Natta solid catalyst (purchased from Yingkou Xiangyang Catalyst Co., Ltd., composition: TiCl4, triethylaluminum, diisobutyl phthalate), 11g of the macromolecular dielectric enhancer, and 5g of tert-butyl hydrogen peroxide were added. Propylene and a small amount of hydrogen were then introduced, maintaining a pressure of 20MPa and a reactor temperature of 75℃ to initiate polymerization. After 2 hours of reaction, unreacted gases were discharged to obtain high dielectric constant polypropylene powder.

[0121] (4) 1000g of the high dielectric constant polypropylene powder and 3.5g of antioxidant composite additive (purchased from Beijing Jiyi Holdings Group Co., Ltd.) are thoroughly mixed and then added to a twin-screw extruder for extrusion granulation to obtain high dielectric constant polypropylene resin granules.

[0122] After preparing thin film samples from high dielectric constant polypropylene resin granules according to standard methods, dielectric tests were performed.

[0123] Example 4

[0124] (1) Preparation of dielectric enhancer:

[0125] First, the reactor was purged twice with argon gas. Under an argon atmosphere, 100g of dicyclohexylmethane-4,4'-diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 55°C, and 73g of glycerol and 0.2g of diisobutyryl peroxide were added. The temperature was then raised to 75°C and stirred at 110 rpm for 20 min. At a reactor temperature of 65°C, 60g of phenyltriethoxysilane was added dropwise at a rate of 6w% phenyltriethoxysilane / min. The mixture was stirred at 90 rpm for 30 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0126] (2) Preparation of macromolecular dielectric enhancers:

[0127] First, argon gas was purged twice in a jacketed 10L high-pressure reactor. After heating to 85℃, 400g of ethylbenzene was added. Under uniform stirring at 400rpm, 55g of ethylaluminoxane co-catalyst was added dropwise. Stirring was continued for 15min under argon protection. Then, 1g of trans-bromophenyl(di(triphenylphosphine))nickel and 2g of the dielectric enhancer were added, and ethylene was introduced. The reaction was carried out at 20MPa for 2.0h. After the reaction was completed, the polymer dielectric enhancer was obtained by centrifugation, drying, and extraction.

[0128] (3) Preparation of polypropylene with high dielectric constant:

[0129] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged twice with argon gas. 1g of MgCl2-supported Ziegler-Natta solid catalyst (purchased from Yingkou Xiangyang Catalyst Co., Ltd., composed of TiCl4, diethylaluminum chloride, and ethyl benzoate), 8g of the macromolecular dielectric enhancer, and 3g of dicumyl peroxide were then added. Propylene and a small amount of hydrogen were then introduced, maintaining the pressure at 15MPa and the reactor temperature at 65℃ to initiate polymerization. After 1.5 hours of reaction, unreacted gases were discharged to obtain polypropylene powder with a high dielectric constant.

[0130] (4) 1000g of the high dielectric constant polypropylene powder and 1.2g of antioxidant composite additive (purchased from Beijing Jiyi Holdings Group Co., Ltd.) are thoroughly mixed and then added to a twin-screw extruder for extrusion granulation to obtain high dielectric constant polypropylene resin granules.

[0131] After preparing thin film samples from high dielectric constant polypropylene resin granules according to standard methods, dielectric tests were performed.

[0132] Example 5

[0133] (1) Preparation of dielectric enhancer:

[0134] First, the reactor was purged with nitrogen three times. Under a nitrogen atmosphere, 100g of isophorone diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 70°C, and 126g of 1,4-butanediol and 0.5g of cumene hydroperoxide were added. The temperature was then raised to 90°C and stirred at 280 rpm for 40 min. At a reactor temperature of 85°C, 95g of diphenyldimethoxysilane was added dropwise at a rate of 9w% diphenyldimethoxysilane / min. The mixture was stirred at 120 rpm for 45 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0135] (2) Preparation of macromolecular dielectric enhancers:

[0136] First, nitrogen gas was purged three times in a jacketed 10L high-pressure reactor. After heating to 110℃, 600g of dichloroethane was added. Under uniform stirring at 800rpm, 80g of methylaluminoxane co-catalyst was gradually added. Stirring continued for 30min under nitrogen protection. Then, 1g of 2,5-dicarboxypyrrole nickel dibromide and 4g of the dielectric enhancer were added, and ethylene was introduced. The pressure was maintained at 30MPa for 5.0h. After the reaction was completed, the polymer dielectric enhancer was obtained by centrifugation, drying, and extraction.

[0137] (3) Preparation of polypropylene with high dielectric constant:

[0138] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged with nitrogen three times. Next, 1g of MgCl2-supported Ziegler-Natta solid catalyst (purchased from Yingkou Xiangyang Catalyst Co., Ltd., composed of TiCl4, ethylaluminum dichloride, and diisobutyl phthalate), 15g of the macromolecular dielectric enhancer, and 6g of tert-butyl hydrogen peroxide were added. Propylene and a small amount of hydrogen were then introduced, maintaining a pressure of 25MPa and a reactor temperature of 90℃ to initiate polymerization. After 3 hours of reaction, unreacted gases were discharged to obtain high dielectric constant polypropylene powder.

[0139] (4) 1000g of the high dielectric constant polypropylene powder and 5.8g of antioxidant composite additive (purchased from Beijing Jiyi Holdings Group Co., Ltd.) are thoroughly mixed and then added to a three-screw extruder for extrusion granulation to obtain high dielectric constant polypropylene resin granules.

[0140] After preparing thin film samples from high dielectric constant polypropylene resin granules according to standard methods, dielectric tests were performed.

[0141] Example 6

[0142] (1) Preparation of dielectric enhancer:

[0143] First, the reactor was purged with argon gas three times. Under an argon atmosphere, 100g of methylcyclohexane diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 60°C, and 100g of pentaerythritol and 0.3g of benzoyl peroxide were added. The temperature was then raised to 80°C and stirred at 210 rpm for 30 min. At a reactor temperature of 70°C, 75g of dicyclopentyldimethoxysilane was added dropwise at a rate of 7w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 100 rpm for 40 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0144] (2) Preparation of macromolecular dielectric enhancers:

[0145] First, argon gas was purged three times in a jacketed 10L high-pressure reactor. After heating to 90℃, 500g of pentaerythritol was added. 70g of ethylaluminoxane co-catalyst was added dropwise under uniform stirring at 650rpm. Stirring continued for 20min under argon protection. Then, 1g of nickel chloride (1-naphthyl)[8-(diphenylphosphino)quinoline] and 3g of the dielectric enhancer were added, and ethylene was introduced. The reaction was carried out at 25MPa for 3.5h. After the reaction was completed, the polymer dielectric enhancer was obtained by centrifugation, drying, and extraction.

[0146] (3) Preparation of polypropylene with high dielectric constant:

[0147] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged three times with argon gas. Next, 1g of a MgCl2-supported Ziegler-Natta solid catalyst (purchased from Yingkou Xiangyang Catalyst Co., Ltd., composed of TiCl4, trimethylaluminum, and 2,2-diphenyl-1,3-propanediol dimethyl ether), 11g of the macromolecular dielectric enhancer, and 5g of di-tert-butyl peroxide were added. Propylene and a small amount of hydrogen were then introduced, maintaining a pressure of 20MPa and a reactor temperature of 75℃ to initiate polymerization. After 2 hours of reaction, unreacted gases were discharged to obtain high dielectric constant polypropylene powder.

[0148] (4) 1000g of the high dielectric constant polypropylene powder and 3.5g of antioxidant composite additive (purchased from Beijing Jiyi Holdings Group Co., Ltd.) are thoroughly mixed and then added to a twin-screw extruder for extrusion granulation to obtain high dielectric constant polypropylene resin granules.

[0149] After preparing thin film samples from high dielectric constant polypropylene resin granules according to standard methods, dielectric tests were performed.

[0150] Comparative Example 1

[0151] The other conditions are the same as in Example 1, except that no large molecular weight dielectric enhancer is added when preparing high dielectric constant polypropylene in step (3), that is:

[0152] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged twice with nitrogen. 1g of MgCl2-supported Ziegler-Natta solid catalyst (composed of TiCl4, triethylaluminum, and diisobutyl phthalate) and 3g of tert-butyl hydrogen peroxide were added. Propylene and a small amount of hydrogen were then introduced, maintaining the pressure at 15MPa and the reactor temperature at 65℃ to initiate polymerization. After 1.5 minutes of reaction, unreacted gases were discharged to obtain polypropylene powder with a high dielectric constant.

[0153] Comparative Example 2

[0154] The other conditions are the same as in Example 1, except that in step (3) when preparing high dielectric constant polypropylene, a macromolecular dielectric enhancer is not added, but 8g of the dielectric enhancer prepared in Example 1 is added, that is:

[0155] A 15L high-pressure reactor with a jacket was heated and evacuated to remove air and water. The reactor was then purged twice with nitrogen. 1g of MgCl2-supported Ziegler-Natta solid catalyst (composed of TiCl4, triethylaluminum, and diisobutyl phthalate), 8g of the dielectric enhancer, and 3g of tert-butyl hydrogen peroxide were added. Propylene and a small amount of hydrogen were then introduced, maintaining the pressure at 15MPa and the reactor temperature at 65℃ to initiate polymerization. After 1.5 minutes of reaction, unreacted gases were discharged to obtain polypropylene powder with a high dielectric constant.

[0156] Comparative Example 3

[0157] The other conditions are the same as in Example 2, except that the amount of dicyclopentyldimethoxysilane added in step (1) is 50g, that is:

[0158] Preparation of dielectric enhancer: First, the reactor was purged with nitrogen three times. Under nitrogen atmosphere, 100g of hexamethylene diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 70℃, and 126g of ethylene glycol and 0.5g of diacetyl peroxide were added. The temperature was then raised to 90℃ and stirred at 280rpm for 40min. At a reactor temperature of 85℃, 50g of dicyclopentyldimethoxysilane was added dropwise at a rate of 9w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 120rpm for 45min until the reaction was complete, thus obtaining the dielectric enhancer.

[0159] Comparative Example 4

[0160] The other conditions are the same as in Example 3, except that the amount of diacetyl peroxide added in step (1) is 0.1 g, that is:

[0161] First, the reactor was purged with nitrogen three times. Under nitrogen atmosphere, 100g of hexamethylene diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 60°C, and 100g of ethylene glycol and 0.1g of diacetyl peroxide were added. The temperature was then raised to 80°C and stirred at 210 rpm for 30 min. At a reactor temperature of 70°C, 75g of dicyclopentyldimethoxysilane was added dropwise at a rate of 7w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 100 rpm for 40 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0162] Comparative Example 5

[0163] The other conditions are the same as in Example 2, except that the amount of dicyclopentyldimethoxysilane added in step (1) is 110g, that is:

[0164] First, the reactor was purged with nitrogen three times. Under a nitrogen atmosphere, 100g of hexamethylene diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 70°C, and 126g of ethylene glycol and 0.5g of diacetyl peroxide were added. The temperature was then raised to 90°C and stirred at 280 rpm for 40 min. At a reactor temperature of 85°C, 110g of dicyclopentyldimethoxysilane was added dropwise at a rate of 9w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 120 rpm for 45 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0165] Comparative Example 6

[0166] The other conditions are the same as in Example 3, except that the amount of diacetyl peroxide added in step (1) is 0.1 g, that is:

[0167] First, the reactor was purged with nitrogen three times. Under nitrogen atmosphere, 100g of hexamethylene diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 60°C, and 100g of ethylene glycol and 0.1g of diacetyl peroxide were added. The temperature was then raised to 80°C and stirred at 210 rpm for 30 min. At a reactor temperature of 70°C, 75g of dicyclopentyldimethoxysilane was added dropwise at a rate of 7w% dicyclopentyldimethoxysilane / min. The mixture was stirred at 100 rpm for 40 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0168] Comparative Example 7

[0169] The other conditions are the same as in Example 4, except that dicumyl peroxide is not added in step (3), that is:

[0170] A 15L jacketed high-pressure reactor was heated and evacuated to remove air and water. The reactor was then purged twice with argon gas. Next, 1g of a MgCl2-supported Ziegler-Natta solid catalyst (composed of TiCl4, diethylaluminum chloride, and ethyl benzoate) and 8g of the macromolecular dielectric enhancer were added. Propylene and a small amount of hydrogen were then introduced, maintaining a pressure of 15MPa and a reactor temperature of 65℃ to initiate polymerization. After 1.5 minutes of reaction, unreacted gases were discharged to obtain high dielectric constant polypropylene powder.

[0171] Comparative Example 8

[0172] The other conditions are the same as in Example 5, except that cumene hydroperoxide is not added in step (1), that is:

[0173] First, the reactor was purged with nitrogen three times. Under a nitrogen atmosphere, 100g of isophorone diisocyanate was weighed into a jacketed 1L reactor. The reactor was heated to 70°C, and 126g of 1,4-butanediol was added. The temperature was then raised to 90°C and stirred at 280 rpm for 40 min. At a reactor temperature of 85°C, 95g of diphenyldimethoxysilane was added dropwise at a rate of 9w% diphenyldimethoxysilane / min. The mixture was stirred at 120 rpm for 45 min until the reaction was complete, thus obtaining the dielectric enhancer.

[0174] Test case

[0175] Analysis and testing methods:

[0176] Preparation method of high dielectric constant polypropylene film sample: High dielectric constant polypropylene granules are placed in a vacuum hot press for hot pressing to obtain high dielectric constant polypropylene film. The hot pressing conditions are: 150℃, pressure of 10MPa, and holding time of 2min.

[0177] Dielectric testing: The polypropylene film sample was tested by first sputtering gold (gold ion sputtering) onto the sample surface, with an electrode diameter of 30 mm. The test was conducted at room temperature (25℃) in a frequency range of 0.1 Hz to 105 Hz to obtain the dielectric constant and dielectric loss of the sample.

[0178] Table 1 Properties of high dielectric constant polypropylene

[0179]

[0180]

[0181] As shown in Table 1, the high dielectric constant polypropylene of the present invention has both a high dielectric constant and a low dielectric loss.

Claims

1. A method for preparing a macromolecular dielectric enhancer, wherein, The method includes: The step of preparing a dielectric enhancer at 65-85°C using a diisocyanate compound of formula (II) and an alkoxysilane of formula (III) as raw materials in the presence of initiator a; wherein the amount of initiator a is 0.2-0.5 parts per 100 parts by mass of the diisocyanate compound, and the initiator a is selected from one or a mixture of diacetyl peroxide, diisobutyryl peroxide, cumene hydroperoxide and benzoyl peroxide; R1, R2, and R4 may be the same or different, and each is independently selected from one of the following: alkyl groups having 1-8 carbon atoms, cycloalkyl groups having 5-8 carbon atoms, aromatic groups having 6-8 carbon atoms, and alkoxy groups having 1-4 carbon atoms; R3 is an alkyl group having 1-4 carbon atoms. R' is an alkene, alkane, alcohol, ether, ketone, aldehyde or ester group with 2-20 carbon atoms, or a cycloalkane or aromatic group with 5-20 carbon atoms; as well as, The step involves reacting the obtained dielectric enhancer and ethylene in the presence of a nickel-based complex catalyst and an alkylaluminoxane co-catalyst at 85-110°C and a pressure of 20-30 MPa for 2-5 hours to obtain the macromolecular dielectric enhancer; the amount of alkylaluminoxane co-catalyst is 55-80 parts and the amount of dielectric enhancer is 2-4 parts, with 1 part by mass of nickel-based complex catalyst. Based on 100 parts by mass of diisocyanate compounds, the amount of alkoxysilane used in the reaction is 60-95 parts; the amount of ethylene used is to maintain a reaction pressure of 20-30 MPa. The diisocyanate compound is selected from one or more of dicyclohexylmethane-4,4'-diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate, and methylcyclohexane diisocyanate; the alkoxysilane is selected from one of dicyclopentyldimethoxysilane, phenyltriethoxysilane, and diphenyldimethoxysilane.

2. The preparation method according to claim 1, wherein, The steps for preparing the dielectric enhancer include: mixing a diisocyanate compound, a solvent, and an initiator a under an inert gas atmosphere, then adding alkoxysilane dropwise at 65-85°C at a rate of 6-9% silane / min, and reacting for 30-45 min to obtain the dielectric enhancer.

3. The preparation method according to claim 2, wherein, The steps for preparing the dielectric enhancer include: mixing a diisocyanate compound, a solvent, and an initiator a at 55-70°C under an inert gas atmosphere, then heating to 75-90°C and stirring at 110-280 rpm for 20-40 min, adding alkoxysilane dropwise at 65-85°C, and then stirring the reaction at 90-120 rpm for 30-45 min to obtain the dielectric enhancer.

4. The preparation method according to claim 1, wherein, The steps for preparing the macromolecular dielectric enhancer include mixing a nickel-based complex, an alkylaluminoxane cocatalyst, and a dielectric enhancer with a solvent under an inert gas atmosphere, introducing ethylene, and reacting to obtain the macromolecular dielectric enhancer.

5. The preparation method according to claim 4, wherein, The steps for preparing the macromolecular dielectric enhancer include adding an alkylaluminoxane co-catalyst dropwise to a solvent under an inert gas atmosphere at 85-110°C and a stirring speed of 400-800 rpm, stirring for 15-30 min, adding a nickel-based complex catalyst and a dielectric enhancer, introducing ethylene to carry out the reaction, and then centrifuging and drying to obtain the macromolecular dielectric enhancer.

6. The preparation method according to any one of claims 1 to 5, wherein, The nickel-based complex catalyst is selected from one of (1-naphthyl)[8-(diphenylphosphino)quinoline]nickel chloride, trans-phenyl bromide (di(triphenylphosphine))nickel, and 2,5-dicarboxypyrrole nickel dibromide; the alkylaluminoxane co-catalyst is selected from one of methylaluminoxane (MAO) and ethylaluminoxane (EAO).

7. The macromolecular dielectric enhancer prepared by the preparation method according to any one of claims 1 to 6.

8. A method for preparing polypropylene with high dielectric constant, wherein, The method comprises preparing the high dielectric constant polypropylene by polymerization reaction using the macromolecular dielectric enhancer as described in claim 7 and propylene as raw materials.

9. The preparation method according to claim 8, wherein, The method includes preparing the high dielectric constant polypropylene by polymerization reaction using the macromolecular dielectric enhancer and propylene as raw materials in the presence of a supported Ziegler-Natta catalyst and initiator b; the macromolecular dielectric enhancer is 8-15 parts by mass of 1 part ... of 1 part by mass of 1 part of 1 part by mass of 1 part of 1 part by mass of 1 part of 1 part by mass of 1 part of 1 part by mass of 1 part of 1 part by mass of 1 part of 1 part by mass of 1 part of 1 part of 1 part by mass of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 1 part of 10. The preparation method according to claim 8, wherein, The polymerization reaction of macromolecular dielectric enhancers and propylene is carried out at a temperature of 65-90℃, a pressure of 15-25MPa, and a reaction time of 1.5-3h.

11. The preparation method according to claim 9, wherein the method comprises mixing a supported Ziegler-Natta catalyst, initiator b and a macromolecular dielectric enhancer under an inert gas atmosphere, introducing propylene and hydrogen gas at a hydrogen concentration of 200ppm-2000ppm, and carrying out a polymerization reaction for 1.5-3h at a temperature of 65-90℃ and a pressure of 15-25MPa to obtain the high dielectric constant polypropylene.

12. The preparation method according to any one of claims 8 to 11, wherein, The method further includes the step of fully mixing the obtained high dielectric constant polypropylene with an antioxidant composite additive and then extruding and granulating it to obtain high dielectric constant polypropylene resin granules, wherein the mass of the high dielectric constant polypropylene is 100 parts and the mass of the antioxidant composite additive is 0.12-0.58 parts.

13. The preparation method according to claim 12, wherein, The antioxidant complex comprises an acid scavenger, a primary antioxidant, and a secondary antioxidant; the acid scavenger is selected from one or a combination of two of metal stearates and hydrotalcite; the primary antioxidant is selected from 2,6-di-tert-butyl-p-cresol, pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 1,3,5-tris(3,5-di-tert-butyl-4-hydroxybenzyl)-S-triazine-2,4,6-(1H,3H,5H)trione, octadecyl β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 1,3,5-di-tert-butyl-4-hydroxyphenyl)propionate, and 1,3,5-di-tert-butyl-4-hydroxyphenyl)propionate. -Trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene and 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane; the co-antioxidant is selected from one or more combinations of dilauryl thiodipropionate, dioctadecyl thiodipropionate, di(tetradecyl)thiodipropionate, trinonylphenyl phosphite, di(octadecyl)pentaerythritol diphosphite, tri(2,4-tert-butylphenyl) phosphite and di(2,4-di-tert-butylphenyl)pentaerythritol diphosphite.

14. The preparation method according to claim 9, wherein, The supported Ziegler-Natta catalyst comprises a main catalyst and an organometallic co-catalyst; the main catalyst is a combination of one or more catalysts selected from ethyl benzoate, phthalic acid monoester or diester, monoether, diether or succinate as internal electron donors, with MgCl2 as support and TiCl4 as active center; the organometallic co-catalyst is composed of alkyl aluminum compounds.

15. The preparation method according to claim 14, wherein, The alkylaluminum compound is selected from one or more combinations of trimethylaluminum, triethylaluminum, triisobutylaluminum, tri-n-hexylaluminum, tri-n-octylaluminum, diethylaluminum chloride, and ethylaluminum dichloride.

16. The preparation method according to claim 9, wherein, The initiator b is selected from one of tert-butyl hydroperoxide, dicumyl peroxide, cumyl hydroperoxide, benzoyl peroxide, and di-tert-butyl peroxide.

17. The high dielectric constant polypropylene prepared by the preparation method according to any one of claims 8 to 16.

18. The use of the high dielectric constant polypropylene of claim 17 in the preparation of thin-film capacitors or lithium battery separators.

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