Heteroaromatic polypropylene modified material as well as preparation method and application thereof
By grafting aromatic heterocyclic compounds in polypropylene films to prepare high-temperature capacitance films, the problem of degradation of performance of polypropylene films at high temperatures is solved, and the high discharge energy density and charge and discharge efficiency are improved at high temperatures.
Patent Information
- Application Number
- CN202510563757.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-30
- Publication Date
- 2025-08-01
AI Technical Summary
The performance of polypropylene dielectric films has sharply decreased at high temperatures, resulting in limited operation of capacitors in extreme environments, especially when the temperature may exceed 120°C in hybrid electric vehicles, the discharge efficiency and energy density are significantly reduced.
An aromatic heterocyclic compound containing alkenyl groups is mixed with polypropylene, and an aromatic heterocyclic polypropylene modified material is prepared by screw grafting reaction, and a high-temperature capacitance film is prepared by bidirectional stretching method to improve the high-temperature performance of the material.
Maintain high discharge energy density and charge and discharge efficiency at high temperatures, improve breakdown field strength, and reduce dielectric loss. It is suitable for high-temperature energy storage dielectric materials.
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Figure CN120399154A_ABST
Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of polymer materials, and particularly relates to an aromatic heterocyclic-containing polypropylene modified material, a preparation method thereof, and an application thereof. Background Art
[0002] A polymer film capacitor is a sandwich-structured capacitor with a polymer film as the dielectric and metal as the electrodes. Due to its advantages such as high voltage resistance, high power density, mechanical flexibility, and low cost, this device has been widely used in fields such as aerospace, electromagnetic weapons, underground oil and gas exploration, and new energy transportation. Currently, commercial polypropylene materials have extremely low dielectric losses and mature large-scale preparation processes, and are the most widely used dielectric materials in the field of film capacitor applications. However, polypropylene dielectric films have problems such as a low upper limit of the long-term working temperature and a sharp decline in performance at high temperatures, which have become the core limiting factors for capacitors operating in extreme environments. For example, in a hybrid electric vehicle, the temperature near the engine may exceed 120 °C. In an environment below 85 °C, the polypropylene film capacitor can maintain a discharge efficiency of more than 95% and a relatively high energy density. However, at a temperature of 125 °C, the discharge energy density and charge-discharge efficiency will rapidly decrease, the leakage current will increase significantly, and the energy storage performance will decline significantly. Summary of the Invention
[0003] In view of this, the purpose of the present invention is to provide an aromatic heterocyclic-containing polypropylene modified material, a preparation method thereof, and an application thereof. This aromatic heterocyclic-modified polypropylene dielectric energy storage material has a high working temperature and can also maintain a high discharge energy density and charge-discharge efficiency at a relatively high working temperature.
[0004] The present invention provides an aromatic heterocyclic-containing polypropylene modified material, which comprises the following raw materials in parts by weight:
[0005] 100 parts of polypropylene, 0.5 - 30 parts of an alkenyl-containing aromatic heterocyclic compound, 0.1 - 10 parts of an initiator;
[0006] The alkenyl-containing aromatic heterocyclic compound is a compound represented by Formula I or Formula II:
[0007]
[0008] In Formula I and Formula II, the R a is selected from one of a substituted or unsubstituted C4 - C6 epoxy 1 - 3 alkenyl, a substituted or unsubstituted C4 - C6 heteroaryl containing only one heteroatom, and a substituted or unsubstituted C4 - C6 biheteroaryl containing only two heteroatoms, and the heteroatom is selected from one or more of O, S, and Se;
[0009] The R b , R cand R d is independently selected from a hydrogen atom and a substituted or unsubstituted C1-C5 alkyl group.
[0010] Preferably, the R a is independently selected from a substituted or unsubstituted C6 epoxy 3-enyl group, a substituted or unsubstituted C4 heteroaryl group containing only one heteroatom, and a substituted or unsubstituted C4 biheteroaryl group containing only two heteroatoms.
[0011] Preferably, the R a is independently selected from one of the groups represented by Formula III to Formula X:
[0012]
[0013] Wherein, X1 to X4 and the X 1 ~X 4 are independently selected from O, S or Se;
[0014] The R1 to R 21 and the R 1 ~R 10 are independently selected from halogen, hydroxyl, amino, aldehyde, carboxyl, isocyanate, acyl chloride, cyano, hydrogen atom, sulfonic acid group, substituted or unsubstituted C1-C5 alkyl group, substituted or unsubstituted C3-C8 cycloalkyl group, substituted or unsubstituted C1-C8 alkoxy group, substituted or unsubstituted C1-C8 ester group, and substituted or unsubstituted C1-C8 amino group.
[0015] Preferably, the substituents in the R1 to R 21 and the R 1 ~R 10 are independently selected from halogen, hydroxyl, amino, aldehyde, carboxyl, isocyanate, acyl chloride, cyano, hydrogen atom, sulfonic acid group, C1-C5 alkyl group, C3-C8 cycloalkyl group, C1-C8 alkoxy group, C1-C8 ester group or C1-C8 amino group.
[0016] Preferably, the initiator is selected from organic peroxide initiators or ketone initiators.
[0017] Preferably, the organic peroxide initiators are selected from one or more of benzoyl peroxide, tert-butyl perbenzoate, di-tert-butyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl hydroperoxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, and 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxynonane;
[0018] The ketone initiators are selected from one or more of bis(pentafluorophenyl)methanone, benzophenone, benzoin dimethyl ether, xanthone, and cyclohexanone.
[0019] Preferably, the polypropylene is homopolypropylene and / or copolymerized polypropylene;
[0020] The ash content of the polypropylene resin is less than 40 ppm, and the flexural modulus is 1000-2200 MPa;
[0021] It also has at least one of the following characteristics: the melt flow rate at 230 °C under a load of 2.16 kg is 0.8-10 g / 10 min; the melting temperature Tm is above 120 °C; the isotacticity is greater than 95%.
[0022] The present invention provides a method for preparing the aromatic heterocyclic polypropylene modified material described in the above technical solution, including the following steps:
[0023] Mix polypropylene and an alkenyl-containing aromatic heterocyclic compound and heat them;
[0024] After the mixture melts, add an initiator for screw grafting reaction, and pelletize to obtain the aromatic heterocyclic polypropylene modified material;
[0025] The alkenyl-containing aromatic heterocyclic compound is a compound represented by Formula I or Formula II:
[0026]
[0027] In Formula I and Formula II, the R a is selected from one of substituted or unsubstituted C4-C6 epoxy 1-3 alkenyl, substituted or unsubstituted C4-C6 heteroaryl containing only one heteroatom, and substituted or unsubstituted C4-C6 biheteroaryl containing only two heteroatoms, and the heteroatom is selected from one or more of O, S, and Se;
[0028] The R b , R c and R d are independently selected from one of a hydrogen atom, substituted or unsubstituted C1-C5 alkyl.
[0029] Preferably, the temperature of the screw grafting reaction is 100-300 °C; the time is 0.5-20 min.
[0030] The present invention provides a high-temperature capacitor film made of the aromatic heterocyclic polypropylene modified material described in the above technical solution.
[0031] The present invention provides an aromatic heterocyclic-containing polypropylene modified material, which comprises the following raw materials in parts by weight: 100 parts of polypropylene, 0.5 - 30 parts of an alkenyl-containing aromatic heterocyclic compound, and 0.1 - 10 parts of an initiator; the alkenyl-containing aromatic heterocyclic compound is a compound represented by Formula I or Formula II. By using the alkenyl-containing aromatic heterocyclic compound represented by Formula I or Formula II to prepare the aromatic heterocyclic-containing polypropylene modified material and using it as a capacitor film in the preparation of high-temperature energy storage dielectric materials, the polypropylene dielectric energy storage material has a high working temperature and can also maintain a high charge-discharge efficiency and discharge energy density at a relatively high working temperature. Experimental results show that: at 125 °C and 300 MV / m, the charge-discharge efficiency of the high-temperature capacitor film prepared from the aromatic heterocyclic-containing polypropylene modified material is 95.5 - 97.6%, and the discharge energy density is 0.78 - 1.21 J / cm 3 , and the breakdown field strength is 553 - 601 MV / m. BRIEF DESCRIPTION OF THE DRAWINGS
[0032] Figure 1 is the NMR spectrum of methyl 2-(benzo[b]thiophen-2-yl)acrylate in Example 1 of the present invention;
[0033] Figure 2 is the NMR spectrum of methyl 2-(oxolan-2-yl)acrylate in Example 2 of the present invention;
[0034] Figure 3 is the NMR spectrum of methyl 2-(thiophen-2-yl)acrylate in Example 3 of the present invention;
[0035] Figure 4 is the NMR spectrum of methyl 2,2'-bithiophen-5-yl methacrylate in Example 5 of the present invention;
[0036] Figure 5 is the NMR spectrum of methyl 2-(pyridin-2-yl)acrylate in Comparative Example 3 of the present invention;
[0037] Figure 6 is a comparative data graph of the discharge energy density and charge-discharge efficiency of the modified materials prepared in the examples and comparative examples. DETAILED DESCRIPTION OF THE INVENTION
[0038] The present invention provides an aromatic heterocyclic-containing polypropylene modified material, which comprises the following raw materials in parts by weight:
[0039] 100 parts of polypropylene, 0.5 - 30 parts of an alkenyl-containing aromatic heterocyclic compound, and 0.1 - 10 parts of an initiator;
[0040] the alkenyl-containing aromatic heterocyclic compound is a compound represented by Formula I or Formula II:
[0041]
[0042] In Formula I and Formula II, the R a is selected from one of a substituted or unsubstituted C4-C6 epoxy 1-3 alkenyl group, a substituted or unsubstituted C4-C6 heteroaryl group containing only one heteroatom, and a substituted or unsubstituted C4-C6 biheteroaryl group containing only two heteroatoms, and the heteroatom is selected from one or more of O, S, and Se;
[0043] The R b , R c and R d are independently selected from one of a hydrogen atom and a substituted or unsubstituted C1-C5 alkyl group.
[0044] The application of the above-mentioned aromatic heterocyclic polypropylene modified material provided by the present invention as a capacitor film in the preparation of a high-temperature energy storage dielectric material. This polypropylene dielectric energy storage material has a high working temperature and can also maintain a high charge-discharge efficiency and discharge energy density at a relatively high working temperature.
[0045] The raw materials for preparing the aromatic heterocyclic polypropylene modified material provided by the present invention include 100 parts of polypropylene; the polypropylene is homopolypropylene and / or copolymerized polypropylene, preferably homopolypropylene. The ash content of the polypropylene is less than 40 ppm, preferably 20 ppm to 35 ppm; the flexural modulus of the polypropylene is 1000 MPa to 2200 MPa, preferably 1500 MPa to 1800 MPa; the polypropylene also has at least one of the following characteristics: Characteristic One: The melt flow rate at 230 °C under a load of 2.16 kg is 0.8 to 10 g / 10 min, preferably 1 to 9 g / 10 min; Characteristic Two: The melting temperature T m is above 120 °C, preferably 120 to 170 °C; Characteristic Three: The isotacticity is greater than 95%, preferably 96 to 98%.
[0046] The raw materials for preparing the aromatic heterocyclic polypropylene modified material provided by the present invention include 0.5 to 30 parts of an alkenyl-containing aromatic heterocyclic compound, specifically it can be 0.5 part, 1.0 part, 1.5 parts, 2.0 parts, 2.5 parts, 3.0 parts, 3.5 parts, 4.0 parts, 4.5 parts, 5.0 parts, 5.5 parts, 6.0 parts, 6.5 parts, 7.0 parts, 7.5 parts, 8.0 parts, 9 parts, 10 parts, 11 parts, 12 parts, 13 parts, 14 parts, 15 parts, 16 parts, 17 parts, 18 parts, 19 parts, 20 parts, 21 parts, 22 parts, 23 parts, 24 parts, 5 parts, 26 parts, 27 parts, 28 parts, 29 parts or 30 parts; preferably 0.5 to 20 parts, more preferably 1 to 10 parts. The alkenyl-containing aromatic heterocyclic compound is a compound represented by Formula I or Formula II:
[0047]
[0048] In Formula I and Formula II, the R a is selected from one of a substituted or unsubstituted C4-C6 epoxy 1-3 alkenyl, a substituted or unsubstituted C4-C6 heteroaryl containing only one heteroatom, and a substituted or unsubstituted C4-C6 biheteroaryl containing only two heteroatoms, and the heteroatom is selected from one or more of O, S, and Se;
[0049] The R b , R c and R d are independently selected from one of a hydrogen atom and a substituted or unsubstituted C1-C5 alkyl.
[0050] In the present invention, the R a is independently selected from one of a substituted or unsubstituted C6 epoxy 3 alkenyl, a substituted or unsubstituted C4 heteroaryl containing only one heteroatom, and a substituted or unsubstituted C4 biheteroaryl containing only two heteroatoms.
[0051] In Formula I or Formula II, the R a is independently selected from one of the groups shown in Formula III to Formula X:
[0052]
[0053] Wherein, X1-X4 and the X 1 -X 4 are independently selected from O, S or Se;
[0054] The R1-R 21 and the R 1 -R 10 are independently selected from halogen, hydroxyl, amino, aldehyde, carboxyl, isocyanate, acyl chloride, cyano, hydrogen atom, sulfonic acid group, substituted or unsubstituted C1-C5 alkyl, substituted or unsubstituted C3-C8 cycloalkyl, substituted or unsubstituted C1-C8 alkoxy, substituted or unsubstituted C1-C8 ester group, and substituted or unsubstituted C1-C8 amino group. The substituted groups in the R1-R 21 and the R 1 -R 10 are independently selected from halogen, hydroxyl, amino, aldehyde, carboxyl, isocyanate, acyl chloride, cyano, hydrogen atom, sulfonic acid group, C1-C5 alkyl, C3-C8 cycloalkyl, C1-C8 alkoxy, C1-C8 ester group or C1-C8 amino group.
[0055] Specifically, the alkenyl-containing aromatic heterocyclic compound is one or more of methyl benzothiophene-2-methylacrylate, methyl oxolene-2-ylmethacrylate, methyl thiophene-2-methylacrylate, and 2-vinylthiophene.
[0056] The raw materials for preparing the aromatic heterocyclic-containing polypropylene modified material provided by the present invention include 0.1 to 10 parts of an initiator, specifically, it can be 0.1 part, 0.2 part, 0.3 part, 0.5 part, 1.0 part, 1.5 part, 2.0 part, 2.5 part, 3.0 part, 3.5 part, 4.0 part, 4.5 part, 5.0 part, 5.5 part, 6.0 part, 7.0 part, 7.5 part, 8.0 part, 9.0 part, 9.5 part or 10 parts; preferably 0.1 to 8 parts, more preferably 0.3 to 5 parts. The initiator is selected from organic peroxide initiators or ketone initiators. The organic peroxide initiators are selected from one or more of benzoyl peroxide, tert-butyl peroxybenzoate, di-tert-butyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl hydroperoxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane and 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxynonane; the ketone initiators are selected from one or more of bis(pentafluorophenyl)methanone, benzophenone, benzoin dimethyl ether, xanthone and cyclohexanone.
[0057] In specific embodiments, by weight, the raw materials for the aromatic heterocyclic-containing polypropylene modified material include:
[0058] 100 parts of polypropylene, 2 parts of an alkenyl-containing aromatic heterocyclic compound, and 0.3 part of an initiator.
[0059] The present invention provides a method for preparing the aromatic heterocyclic-containing polypropylene modified material according to the above technical solution, including the following steps:
[0060] Mix polypropylene and an alkenyl-containing aromatic heterocyclic compound and heat them;
[0061] After the mixture melts, add an initiator for a screw grafting reaction, granulate, and obtain the aromatic heterocyclic-containing polypropylene modified material;
[0062] The alkenyl-containing aromatic heterocyclic compound is a compound represented by Formula I or Formula II:
[0063]
[0064] In Formula I and Formula II, the R a is selected from one of a substituted or unsubstituted C4-C6 epoxy 1-3 alkenyl, a substituted or unsubstituted C4-C6 heteroaryl containing only one heteroatom, and a substituted or unsubstituted C4-C6 biheteroaryl containing only two heteroatoms, and the heteroatom is selected from one or more of O, S, and Se;
[0065] The R b , R c and R d are independently selected from one of a hydrogen atom and a substituted or unsubstituted C1-C5 alkyl group.
[0066] In the present invention, the temperature of the screw grafting reaction is 100 - 300 °C, preferably 120 - 280 °C, more preferably 150 - 250 °C; the time is 0.5 - 20 min, preferably 1 - 15 min, more preferably 2 - 10 min. The length-diameter ratio of the twin-screw extruder used is 52:1.
[0067] In a specific embodiment, the temperature of the screw grafting reaction is 200 °C and the time is 2.5 min.
[0068] The present invention provides a high-temperature capacitor film, which is prepared from the aromatic heterocyclic-containing polypropylene modified material described in the above technical solution.
[0069] The present invention prepares the aromatic heterocyclic-containing polypropylene modified material by a biaxial stretching method.
[0070] By adopting the alkenyl-containing aromatic heterocyclic compound shown in the above formula I or formula II, the capacitor film has a higher working temperature, and has a higher discharge energy density, charge-discharge efficiency and breakdown field strength at high temperature.
[0071] In order to further illustrate the present invention, the following examples are used to describe in detail an aromatic heterocyclic-containing polypropylene modified material and its preparation method and application provided by the present invention, but they should not be construed as limiting the protection scope of the present invention.
[0072] Example 1
[0073] Synthesis process of methyl benzo[b]thiophene-2-yl methacrylate:
[0074] Dissolve benzo[b]thiophene-2-methanol (10 mmol) and the catalyst triethylamine (12 mmol) in dichloromethane and place them in a 500 mL single-necked flask. Under an atmosphere of 0 °C, drop methylacryloyl chloride (12 mmol) dissolved in dichloromethane into the above mixed solution. After the dropping is completed, react for 10 hours. After the reaction is completed, quench the reaction with saturated sodium bicarbonate solution, then extract it 3 times with dichloromethane, collect the organic phase, dry it with anhydrous magnesium sulfate, concentrate it under reduced pressure and finally dry it in vacuo for 5 hours to obtain methyl benzo[b]thiophene-2-yl methacrylate; Figure 1 is the NMR spectrum of methyl benzo[b]thiophene-2-yl methacrylate;
[0075] 10.00 kg of pure polypropylene powder (Borealis - grade HC300BF), 0.20 kg of benzothiophene - 2 - methyl methacrylate, and 0.03 kg of bis(pentafluorophenyl) ketone were thoroughly mixed in a 30 L high - speed mixer. Then, the above mixture was continuously added into a twin - screw extruder preheated to 200 °C (length - diameter ratio 52:1) through a feeder for grafting reaction. The back - mixing ratio of the screw combination was adjusted, and the residence time was controlled at 2.5 min. After passing through water - ring pelletization, aromatic - heterocyclic - containing polypropylene modified material A1 was obtained.
[0076] Example 2.
[0077] Synthesis process of oxolane - 2 - yl methyl methacrylate:
[0078] 2 - Oxolane methanol (10 mmol) and catalyst triethylamine (12 mmol) were dissolved in dichloromethane and placed in a 500 mL single - necked flask. Methacryloyl chloride (12 mmol) dissolved in dichloromethane was added dropwise to the above mixed solution under an atmosphere of 0 °C. After the addition was complete, the reaction was carried out for 10 hours. After the reaction ended, the reaction was quenched with saturated sodium bicarbonate solution, and then it was extracted 3 times with dichloromethane. The organic phase was collected, dried with anhydrous magnesium sulfate, concentrated under reduced pressure, and finally dried in vacuo for 5 hours to obtain oxolane - 2 - yl methyl methacrylate; Figure 2 is the NMR spectrum of oxolane - 2 - yl methyl methacrylate;
[0079] 10.00 kg of pure polypropylene powder (Borealis - grade HC300BF), 0.20 kg of oxolane - 2 - yl methyl methacrylate, and 0.03 kg of bis(pentafluorophenyl) ketone were thoroughly mixed in a 30 L high - speed mixer. Then, the above mixture was continuously added into a twin - screw extruder preheated to 200 °C (length - diameter ratio 52:1) through a feeder for grafting reaction. The back - mixing ratio of the screw combination was adjusted, and the residence time was controlled at 2.5 min. After passing through water - ring pelletization, aromatic - heterocyclic - containing polypropylene modified material A2 was obtained.
[0080] Example 3.
[0081] Synthesis process of thiophene - 2 - methyl methacrylate:
[0082] Dissolve 2 - thiophene methanol (10 mmol) and the catalyst triethylamine (12 mmol) in dichloromethane in a 500 mL single - necked flask. Under an atmosphere of 0 °C, add methacryloyl chloride (12 mmol) dissolved in dichloromethane dropwise to the above - mentioned mixed solution. After the dropwise addition, react for 10 hours. After the reaction is completed, quench the reaction with saturated sodium bicarbonate solution, then extract it 3 times with dichloromethane, collect the organic phase, dry it with anhydrous magnesium sulfate, concentrate it under reduced pressure, and finally dry it under vacuum for 5 hours to obtain methyl 2 - thiophene - methacrylate; Figure 3 It is the NMR spectrum of methyl 2 - thiophene - methacrylate;
[0083] Fully mix 10.00 kg of pure polypropylene powder (Borealis - grade HC300BF), 0.20 kg of methyl 2 - thiophene - methacrylate, and 0.03 kg of bis(pentafluorophenyl) ketone in a 30 L high - speed mixer. Then, continuously add the above - mentioned mixture to a twin - screw extruder preheated to 200 °C (length - to - diameter ratio 52:1) through a feeder for grafting reaction. Adjust the back - mixing ratio of the screw combination, control the residence time to be 2.5 min, and granulate through water - cutting to obtain the aromatic heterocyclic - containing polypropylene modified material A3.
[0084] Example 4.
[0085] Fully mix 10.00 kg of pure polypropylene powder (Borealis - grade HC300BF), 0.20 kg of 2 - vinylthiophene, and 0.03 kg of bis(pentafluorophenyl) ketone in a 30 L high - speed mixer. Then, continuously add the above - mentioned mixture to a twin - screw extruder preheated to 200 °C (length - to - diameter ratio 52:1) through a feeder for grafting reaction. Adjust the back - mixing ratio of the screw combination, control the residence time to be 2.5 min, and granulate through water - cutting to obtain the aromatic heterocyclic - containing polypropylene modified material A4.
[0086] Example 5.
[0087] Synthesis process of methyl 2,2'-bis(thiophen)-5 - yl methacrylate:
[0088] Dissolve 2,2'-bithiophen]-5 - yl methanol (10 mmol) and the catalyst triethylamine (12 mmol) in dichloromethane in a 500 mL single - necked flask. Under an atmosphere of 0 °C, add methacryloyl chloride (12 mmol) dissolved in dichloromethane dropwise to the above - mentioned mixed solution. After the dropwise addition, react for 10 hours. After the reaction is completed, quench the reaction with saturated sodium bicarbonate solution, then extract it 3 times with dichloromethane, collect the organic phase, dry it with anhydrous magnesium sulfate, concentrate it under reduced pressure, and finally dry it under vacuum for 5 hours to obtain methyl 2,2'-bis(thiophen)-5 - yl methacrylate; Figure 41H NMR spectrum of 2,2'-bithiophen]-5-yl methyl methacrylate;
[0089] 10.00 kg of pure polypropylene powder (Borealis - grade HC300BF), 0.20 kg of 2,2'-bithiophen]-5-yl methyl methacrylate, and 0.03 kg of bis(pentafluorophenyl) ketone were thoroughly mixed in a 30 L high-speed mixer. Then, the above mixture was continuously added to a twin-screw extruder preheated to 200 °C (length-to-diameter ratio 52:1) through a feeder for grafting reaction. The backmixing ratio of the screw combination was adjusted, and the residence time was controlled at 2.5 min. After passing through water granulation, the aromatic heterocyclic polypropylene modified material A5 was obtained.
[0090] Comparative Example 1.
[0091] Pure polypropylene powder was used as Comparative Example B1.
[0092] Comparative Example 2.
[0093] 10.00 kg of pure polypropylene powder (Borealis - grade HC300BF), 0.20 kg of 2-morpholinoethyl methacrylate, and 0.03 kg of bis(pentafluorophenyl) ketone were thoroughly mixed in a 30 L high-speed mixer. Then, the above mixture was continuously added to a twin-screw extruder preheated to 200 °C (length-to-diameter ratio 52:1) through a feeder for grafting reaction. The backmixing ratio of the screw combination was adjusted, and the residence time was controlled at 2.5 min. After passing through water granulation, the aromatic heterocyclic polypropylene modified material B2 was obtained.
[0094] Comparative Example 3.
[0095] Synthesis process of 2-pyridylmethyl methacrylate:
[0096] 2-Pyridinemethanol (10 mmol) and catalyst triethylamine (12 mmol) were dissolved in dichloromethane and placed in a 500 mL single-neck flask. Methacryloyl chloride (12 mmol) dissolved in dichloromethane was added dropwise to the above mixed solution under an atmosphere of 0 °C. After the addition was complete, the reaction was carried out for 10 hours. After the reaction was completed, the reaction was quenched with saturated sodium bicarbonate solution, and then it was extracted 3 times with dichloromethane. The organic phase was collected, dried over anhydrous magnesium sulfate, concentrated under reduced pressure, and finally dried in vacuo for 5 hours to obtain the compound 2-pyridylmethyl methacrylate; Figure 5 1H NMR spectrum of 2-pyridylmethyl methacrylate;
[0097] 10.00 kg of pure polypropylene powder (Borealis, grade HC300BF), 0.20 kg of 2-pyridylmethyl methacrylate, and 0.03 kg of bis(pentafluorophenyl) ketone were thoroughly mixed in a 30 L high-speed mixer. Then, the above mixture was continuously added to a twin-screw extruder preheated to 200 °C (length-to-diameter ratio 52:1) through a feeder for grafting reaction. The backmixing ratio of the screw combination was adjusted, and the residence time was controlled at 2.5 min. After passing through a water ring pelletizer, a polypropylene modified material B3 containing aromatic heterocycles was obtained.
[0098] All the powders obtained above were respectively prepared into film products by a biaxial stretching method, and various performance parameters of all the obtained film products were tested. The results are shown in Table 1. Table 1 is a summary of the basic characterization test results of the materials described in the examples and comparative examples, and a summary of the dielectric and discharge energy performance test results of the films of the materials.
[0099] Table 1
[0100]
[0101] From the test results in Table 1 above, compared with Comparative Example 1, the flexural modulus and film thickness of Examples 1 to 5 are not much different, indicating that there is not much difference in the basic performance test after grafting aromatic heterocyclic groups onto pure polypropylene powder; further, it shows that grafting aromatic hybrid groups onto polypropylene materials is successful.
[0102] Compared with Comparative Example 1, the breakdown field strength, discharge energy density, and charge-discharge efficiency of Examples 1 to 5 have been significantly improved, indicating that the film materials of aromatic heterocycle-grafted modified polypropylene not only have a high breakdown field strength and low dielectric loss value, but also can maintain a high discharge energy density and charge-discharge efficiency at a higher working temperature; moreover, compared with Examples 1 to 5, Comparative Example 2 containing non-aromatic oxygen-containing heterocyclic groups has a lower breakdown field strength, discharge energy density, charge-discharge efficiency, and a higher dielectric loss, proving that aromatic heterocycle grafting modification is beneficial to improving dielectric properties and enhancing energy storage performance; further, compared with Examples 1 to 5, Comparative Example 3 with other types of aromatic heterocycle modifications containing ester groups has a poor effect in improving the breakdown field strength, discharge energy density, charge-discharge efficiency, etc., indicating that the combined effect of ester groups and aromatic heterocycle grafting modification improves the problem of poor energy storage performance of polypropylene at high temperatures. As Figure 6 shown, Figure 6 is a comparison data chart of discharge energy density and efficiency in the examples and comparative examples.
[0103] As can be seen from the above embodiments, the present invention provides an aromatic heterocyclic polypropylene modified material, which comprises the following raw materials in parts by weight: 100 parts of polypropylene, 0.5 to 30 parts of an alkenyl-containing aromatic heterocyclic compound, and 0.1 to 10 parts of an initiator; the alkenyl-containing aromatic heterocyclic compound is a compound represented by Formula I or Formula II. The present invention prepares an aromatic heterocyclic polypropylene modified material by using an alkenyl-containing aromatic heterocyclic compound represented by Formula I or Formula II, and uses it as a capacitor film in the preparation of a high-temperature energy storage dielectric material. The polypropylene dielectric energy storage material has a high working temperature, and can also maintain a high charge-discharge efficiency and discharge energy density at a relatively high working temperature. Experimental results show that: at 125 °C and 300 MV / m, the charge-discharge efficiency of the high-temperature capacitor film prepared from the aromatic heterocyclic polypropylene modified material is 95.5 to 97.6%, and the discharge energy density is 0.78 to 1.21 J / cm 3 , and the breakdown field strength is 553 to 601 MV / m.
[0104] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and modifications can be made, and these improvements and modifications should also be regarded as the protection scope of the present invention.
Claims
1. A kind of aromatic heterocyclic polypropylene modified material, by weight, comprising the following raw materials: 100 parts of polypropylene, 0.5 - 30 parts of alkenyl-containing aromatic heterocyclic compound, 0.1 - 10 parts of initiator; The alkenyl-containing aromatic heterocyclic compound is the compound shown in Formula I or Formula II: In Formula I and Formula II, the R a is selected from one of substituted or unsubstituted C4-C6 epoxy 1-3 alkenyl, substituted or unsubstituted C4-C6 heteroaryl containing only one heteroatom, and substituted or unsubstituted C4-C6 biheteroaryl containing only two heteroatoms, and the heteroatom is selected from one or more of O, S, and Se; Said R b , R c and R d are each independently selected from a hydrogen atom, or a substituted or unsubstituted C1-C5 alkyl group.
2. The aromatic heterocyclic-containing polypropylene modified material according to claim 1, wherein Said R a Independently selected from one of substituted or unsubstituted C6 epoxy 3-enyl, substituted or unsubstituted C4 heteroaryl containing only one heteroatom, and substituted or unsubstituted C4 biheteroaryl containing only two heteroatoms.
3. The aromatic heterocyclic-containing polypropylene modified material according to claim 1, wherein The R a is independently selected from one of the groups represented by Formula III to Formula X: wherein, X1 to X4 and said X 1 to X 4 are independently selected from O, S or Se; The R1 to R 21 and the R 1 to R 10 are independently selected from halogen, hydroxyl, amino, aldehyde, carboxyl, isocyanate, acyl chloride, cyano, hydrogen atom, sulfonic acid group, substituted or unsubstituted C1-C5 alkyl, substituted or unsubstituted C3-C8 cycloalkyl, substituted or unsubstituted C1-C8 alkoxy, substituted or unsubstituted C1-C8 ester group, substituted or unsubstituted C1-C8 amino group.
4. The aromatic heterocyclic-containing polypropylene modified material according to claim 3, characterized in that, The R1 to R 21 and the R 1 to R 10 The substituted groups in are independently selected from halogen, hydroxyl, amino, aldehyde, carboxyl, isocyanate, acyl chloride, cyano, hydrogen atom, sulfonic acid group, C1-C5 alkyl group, C3-C8 cycloalkyl group, C1-C8 alkoxy group, C1-C8 ester group or C1-C8 amine group.
5. The aromatic heterocyclic-containing polypropylene modified material according to claim 3, characterized in that, The initiator is selected from organic peroxide initiators or ketone initiators.
6. The aromatic heterocyclic-containing polypropylene modified material according to claim 5, characterized in that, The organic peroxide initiators are selected from one or more of benzoyl peroxide, tert-butyl perbenzoate, di-tert-butyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert-butyl hydroperoxide, dicumyl peroxide, 2,5-dimethyl-2,5-bis(tert-butylperoxy)hexane, and 3,6,9-triethyl-3,6,9-trimethyl-1,4,7-triperoxynonane; The ketone initiators are selected from one or more of bis(pentafluorophenyl) ketone, benzophenone, benzoin dimethyl ether, xanthone, and cyclohexanone.
7. The aromatic heterocyclic-containing polypropylene modified material according to claim 1, wherein The polypropylene is homopolypropylene and / or copolymerized polypropylene; The ash content of the polypropylene resin is less than 40 ppm, and the flexural modulus is 1000 - 2200 MPa; It also has at least one of the following characteristics: The melt flow rate at 230 °C under a load of 2.16 kg is 0.8 - 10 g / 10 min; the melting temperature Tm is above 120 °C; the isotacticity is greater than 95%.
8. A preparation method of the aromatic heterocyclic polypropylene modified material according to claim 1, comprising the following steps: Mix polypropylene and the alkenyl-containing aromatic heterocyclic compound and heat; After the mixture is melted, add the initiator for screw grafting reaction, and pelletize to obtain the aromatic heterocyclic polypropylene modified material; The alkenyl-containing aromatic heterocyclic compound is the compound shown in Formula I or Formula II: In Formula I and Formula II, the R a is selected from one of a substituted or unsubstituted C4-C6 epoxy 1-3 alkenyl, a substituted or unsubstituted C4-C6 heteroaryl containing only one heteroatom, and a substituted or unsubstituted C4-C6 biheteroaryl containing only two heteroatoms, and the heteroatom is selected from one or more of O, S, and Se; Said R b , R c and R d are independently selected from a hydrogen atom, or a substituted or unsubstituted C1-C5 alkyl group.
9. The preparation method according to claim 8, characterized in that, The temperature of the screw grafting reaction is 100 - 300 °C; the time is 0.5 - 20 min.
10. A high-temperature capacitive film, characterized in that, Prepared from the aromatic heterocyclic polypropylene modified material according to any one of claims 1 - 7.