High-frequency-resistant and high-voltage-resistant wire and cable material and preparation method thereof

Abstract

According to the high-frequency-resistant and high-voltage-resistant wire and cable material disclosed by the invention, polyethylene is adopted as main body resin and is a non-polar material, the dipole moment of the polyethylene is 0, the dielectric loss of the polyethylene is very low and is 10 <-4 >, and thermal breakdown of higher voltage can be realized under high frequency due to the relatively low dielectric loss. Meanwhile, the insulating heat-conducting material with low dielectric loss and high heat conductivity coefficient is selected, when the polyethylene material generates heat at high frequency, the electric wire and cable material has good heat conductivity coefficient and small temperature rise, so that the voltage of heat breakdown resistance of the electric wire and cable material can be further improved, and the polyethylene and the insulating heat-conducting material have excellent insulativity, so that the service life of the electric wire and cable material is prolonged. The wire and cable material still has the volume resistivity of more than 1015, and has excellent insulating property. The high-frequency-resistant and high-voltage-resistant wire and cable material provided by the invention has good mechanical properties, is resistant to high frequency and high voltage, has a wide application prospect, and is particularly suitable for manufacturing various wires and cables in the high-frequency and high-voltage field.

Description

Technical Field

[0001] The present invention relates to the technical field of cable materials, and particularly relates to a high-frequency and high-voltage resistant wire and cable material and a preparation method thereof. Background Art

[0002] The non-metallic outer sheath or insulating layer of wire and cable mainly functions as ground insulation, waterproofing, mechanical protection, etc., and serves as the first protective layer of wire and cable. In a power frequency (50Hz) voltage environment, the breakdown voltage of wire and cable can range from dozens of kilovolts to hundreds of kilovolts. When wire and cable operates in a high-frequency environment, such as in a 400±100kHz environment, after the high-frequency electric field is excited, due to the dielectric loss of the raw materials for preparation and the raw materials themselves, wire and cable generates heat under the changing electric field in the electric field, resulting in an increase in the temperature of the insulating layer of wire and cable. Especially in the case of a high-voltage electric field, due to more heat generated by dielectric loss, it cannot be dissipated in a short time. The accumulation of heat causes the temperature of the polymer to rise, resulting in a sharp increase in the conductance of the polymer according to an exponential law. The conductance loss generates more heat, further increasing the temperature. The temperature of wire and cable rises sharply, leading to oxidation, melting and coking of the polymer, resulting in breakdown and ultimately failure of the insulation of wire and cable. Summary of the Invention

[0003] The main purpose of the present invention is to provide a high-frequency and high-voltage resistant wire and cable material made of polyethylene and insulating and heat-conducting materials, which has a leakage current of no more than 100mA after withstanding a voltage of 5000V for 60s at a frequency of 400±100kHz.

[0004] To achieve the above purpose, the present invention provides a high-frequency and high-voltage resistant wire and cable material. Calculated by weight, the preparation materials of the high-frequency and high-voltage resistant wire and cable material include the following components:

[0005] Polyethylene: 30 - 50 parts;

[0006] Insulating and heat-conducting material: 25 - 50 parts.

[0007] In some embodiments of the present application, the tensile strength of the polyethylene is greater than 17Mpa.

[0008] In some embodiments of the present application, the insulating and heat-conducting material includes at least one of α-Al2O3, boron nitride, and aluminum nitride.

[0009] In some embodiments of the present application, the average particle size of the insulating and heat-conducting material is 1 - 10μm.

[0010] In some embodiments of the present application, the average particle size of the insulating and heat-conducting material is 4 - 7μm.

[0011] In some embodiments of the present application, the preparation materials for the high-frequency and high-voltage resistant wire and cable compound further include 5-10 parts of polyolefin elastomer, and the polyolefin elastomer includes at least one of thermoplastic elastomers polymerized from metallocene-catalyzed ethylene and α-olefins, ethylene propylene diene monomer (EPDM), and ethylene propylene copolymer (EPM).

[0012] In some embodiments of the present application, the preparation materials for the high-frequency and high-voltage resistant wire and cable compound further include 1-5 parts of compatibilizer, and the compatibilizer includes at least one of polyolefin elastomer grafts and polyethylene grafts.

[0013] In some embodiments of the present application, the preparation materials for the high-frequency and high-voltage resistant wire and cable compound further include 0.3-0.5 parts of antioxidant, and the antioxidant includes at least one of hindered phenol main antioxidants and thioether antioxidants.

[0014] In some embodiments of the present application, the preparation materials for the high-frequency and high-voltage resistant wire and cable compound further include 0.3-1 part of coupling agent, and the coupling agent includes at least one of aluminate coupling agents and titanate coupling agents.

[0015] In some embodiments of the present application, the preparation materials for the high-frequency and high-voltage resistant wire and cable compound further include 0.3-1 part of sensitizer, and the sensitizer includes at least one of trimethylolpropane tri(meth)acrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, triallyl isocyanate, or 1,3-butanediol dimethacrylate.

[0016] To achieve the above object, the present invention also provides a method for preparing a high-frequency and high-voltage resistant wire and cable compound, including the following steps:

[0017] Masterbatch processing: Mixing polyethylene and insulating and heat-conducting materials according to the ratio in a kneader, and then extruding, drawing into strips, and pelletizing through an extrusion device to obtain masterbatch particles;

[0018] Extruding wire: Extruding the obtained masterbatch particles through an extrusion device to obtain semi-finished wire.

[0019] Irradiation process: Irradiating the above semi-finished wire through an irradiation device to obtain the high-frequency and high-voltage resistant wire and cable compound.

[0020] In some embodiments of the present application, in the masterbatch processing step, when mixing polyethylene and insulating and heat-conducting materials in the kneader, polyolefin elastomer, compatibilizer, antioxidant, coupling agent, or sensitizer can also be added for mixing;

[0021] In some embodiments of the present application, in the masterbatch processing step, the kneading temperature of the kneader is 100-130 °C, and the kneading time is 10-20 min;

[0022] In some embodiments of the present application, in the masterbatch processing step, the extrusion temperature of the extrusion equipment is 130 - 190 °C;

[0023] In some embodiments of the present application, in the extrusion wire step, the extrusion temperature of the extrusion equipment is 130 - 190 °C;

[0024] In some embodiments of the present application, in the irradiation process step, the irradiation dose of the irradiation equipment is 60 - 200 kGy.

[0025] Beneficial effects that the present invention can achieve:

[0026] The high-frequency and high-voltage resistant wire and cable material of the present invention uses polyethylene as the main resin. It is a non-polar material with a dipole moment of 0 and a very low dielectric loss of 10 -4 . The lower dielectric loss can achieve higher-voltage thermal breakdown at high frequencies. At the same time, an insulating and heat-conducting material with a lower dielectric loss and a higher thermal conductivity is selected. When the polyethylene material generates heat at high frequencies, due to the good thermal conductivity of the wire and cable material, its temperature rise is small, which can further increase the voltage for heat breakdown resistance. Moreover, because both polyethylene and the insulating and heat-conducting material have excellent insulation properties, the wire and cable material still has a volume resistivity of 10 15 or more, and has excellent insulation performance. The high-frequency and high-voltage resistant wire and cable material provided by the present invention has good mechanical properties, is resistant to high frequencies and high voltages at the same time, and has a broad application prospect, especially suitable for the manufacture of various wires and cables in the high-frequency and high-voltage fields. Specific embodiments

[0027] It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0028] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0029] In the present invention, descriptions such as "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0030] The present invention provides a high-frequency voltage resistant wire and cable material. The high-frequency voltage resistant wire and cable material preparation material comprises the following components calculated by weight:

[0031] Polyethylene: 30-50 parts;

[0032] Insulating thermal conductive material: 25-50 parts;

[0033] The leakage current of high-frequency and high-voltage wire and cable materials shall not exceed 100mA after withstanding the voltage of 5000V and 60s at a frequency of 400±100kHz.

[0034] Polymers are composed of many atoms connected by covalent bonds. Valence electrons are basically in a relatively stable low-energy state. Therefore, polymer materials are generally insulators with a volume resistivity of up to 10 8 As mentioned above, it has a good withstand voltage level under power frequency, up to hundreds of kV, but under high frequency, the withstand voltage of some polymer materials will drop greatly, which is mainly related to the polarity of the polymer materials, dielectric loss and the frequency characteristics of the electric field. Polymer materials are divided into non-polar, weakly polar, medium polar and strongly polar materials. From the perspective of microstructure, polarity is mainly caused by the misalignment of the positive and negative charge centers in the molecules, that is, molecular polarity. The size of the dipole moment is often used to represent the size of the molecular polarity. When the polymer material is placed in an electric field, due to the existence of the dipole moment, the dipoles of its molecules are arranged along the direction of the electric field, resulting in the orientation of the molecules, which are polarized by the electric field. Since the polar molecules need to overcome their own inertia and rotational resistance when they rotate along the external electric field, part of the electrical energy will be consumed and converted into heat energy. That is dielectric loss. When the frequency is very low, all polarizations have sufficient time to keep up with the changes in the electric field, so the energy consumption is very low and the heat generated is less. However, when the frequency becomes higher, the polar polymer material will consume part of the electrical energy to overcome the internal friction resistance due to dipole rotation under the alternating electric field, and the conversion into heat energy will increase significantly, that is, the dielectric loss will increase significantly. High dielectric loss will cause the material to heat up, age and even be damaged, resulting in breakdown at a lower voltage, the so-called thermal breakdown.

[0035] The high-frequency and high-voltage resistant wire and cable material of the present invention uses polyethylene as the main resin. It is a non-polar material with a dipole moment of 0 and a very low dielectric loss of 10 -4 . The lower dielectric loss can achieve thermal breakdown at a higher voltage under high frequencies. At the same time, an insulating and heat-conducting material with a lower dielectric loss and a higher thermal conductivity is selected. When the polyethylene material generates heat at high frequencies, due to the good thermal conductivity of the wire and cable material, its temperature rise is small, which can further increase the voltage resistant to thermal breakdown. Moreover, because both polyethylene and the insulating and heat-conducting material have excellent insulation properties, the wire and cable material still has a volume resistivity of 10 15 or more, has excellent insulation performance, and can achieve its high-voltage resistance performance under high-frequency conditions.

[0036] Polyethylene is a thermoplastic plastic polymerized from ethylene. Due to the different densities of the resins obtained by different polymerization methods, it is divided into high-density polyethylene (HDPE), medium-density polyethylene (MDPE), linear low-density polyethylene (LLDPE), and low-density polyethylene (LDPE).

[0037] In some embodiments of the present application, the tensile strength of polyethylene is greater than 17 Mpa. The tensile strength within this range is beneficial to improving the tensile strength of the wire and cable.

[0038] In some embodiments of the present application, the insulating and heat-conducting material includes at least one of α-Al2O3, boron nitride, and aluminum nitride. The dielectric losses of these three insulating and heat-conducting materials are relatively low, and thermal breakdown at a higher voltage can be achieved under high frequencies.

[0039] In some embodiments of the present application, the average particle size of the insulating and heat-conducting material is 1-10 μm.

[0040] In some embodiments of the present application, the average particle size of the insulating and heat-conducting material is 4-7 μm. If the particle size is too large, its own voltage resistance performance will be affected and the voltage resistance performance will decline. If the particle size is too small, the dispersibility is poor, which affects the fluidity and processing performance.

[0041] In some embodiments of the present application, the preparation material of the high-frequency and high-voltage resistant wire and cable material further includes a polyolefin elastomer. The polyolefin elastomer includes at least one of a thermoplastic elastomer polymerized from ethylene and α-olefin catalyzed by metallocene, ethylene propylene diene monomer (EPDM), and ethylene propylene copolymer (EPM). The addition of the polyolefin elastomer can improve the compatibility between polyethylene and the insulating and heat-conducting material, can increase the elongation at break of the wire and cable material, and thus improve its toughness and the mechanical properties of the wire and cable material.

[0042] In some embodiments of the present application, the preparation materials for high-frequency and high-voltage resistant wire and cable materials further include a compatibilizer, which includes at least one of a polyolefin elastomer graft and a polyethylene graft. The polyolefin elastomer graft includes a maleic anhydride graft; the polyethylene graft includes a maleic anhydride graft. The compatibilizer can improve the bonding force between polyethylene and the insulating and heat-conducting material, can improve the tensile strength and elongation at break of the wire and cable material, and further improve its tensile strength and toughness, and further improve the mechanical properties of the wire and cable material.

[0043] In some embodiments of the present application, the preparation materials for high-frequency and high-voltage resistant wire and cable materials further include an antioxidant, which includes at least one of a hindered phenol main antioxidant and a thioether antioxidant. By adding an antioxidant, it is beneficial to improve the antioxidant performance and aging resistance of the wire and cable material, and extend the service life of the wire and cable.

[0044] In some embodiments of the present application, the preparation materials for high-frequency and high-voltage resistant wire and cable materials further include a coupling agent, which includes at least one of an aluminate coupling agent and a titanate coupling agent. The coupling agent can improve the bonding force between polyethylene and the insulating and heat-conducting material, can improve the elongation at break of the wire and cable material, and further improve its toughness, and improve the mechanical properties of the wire and cable material.

[0045] In some embodiments of the present application, the preparation materials for high-frequency and high-voltage resistant wire and cable materials further include a sensitizer, which includes at least one of trimethylolpropane tri(meth)acrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, triallyl isocyanate or 1,3-butanediol dimethacrylate. The addition of the sensitizer can improve the crosslinking degree of the irradiation process and reduce the irradiation dose.

[0046] In some embodiments, calculated by weight, the preparation materials for high-frequency and high-voltage resistant wire and cable materials include the following components:

[0047] Polyethylene: 30-50 parts, insulating and heat-conducting material: 25-50 parts. For example, the polyethylene can be any weight part in the range of 30-50 parts such as 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, etc.; the insulating and heat-conducting material can be any weight part in the range of 25-50 parts such as 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, etc.

[0048] Under the limitation of the above weight parts, it is beneficial to promote the mixing of various raw materials, which not only meets the high-frequency and high-voltage resistance performance, but also can achieve certain mechanical properties such as strength and toughness.

[0049] In some embodiments, calculated by weight, the preparation materials for high-frequency and high-voltage resistant wire and cable materials further include the following components:

[0050] Polyolefin elastomer: 5 - 10 parts; compatibilizer: 1 - 5 parts; antioxidant: 0.3 - 0.5 parts; coupling agent: 0.3 - 1 part; sensitizer: 0.3 - 1 part. For example, the polyolefin elastomer can be any weight part within the range of 5 - 10 parts such as 5 parts, 7 parts, 10 parts, etc.; the compatibilizer can be any weight part within the range of 1 - 5 parts such as 1 part, 3 parts, 5 parts, etc.; the antioxidant can be any weight part within the range of 0.3 - 0.5 parts such as 0.3 parts, 0.4 parts, 0.5 parts, etc.; the coupling agent can be any weight part within the range of 0.3 - 1 part such as 0.3 parts, 0.5 parts, 0.8 parts, 1 part, etc.; the sensitizer can be any weight part within the range of 0.3 - 1 part such as 0.3 parts, 0.5 parts, 0.8 parts, 1 part, etc.

[0051] The addition of the above components can further improve the mechanical properties such as strength and toughness of the wire and cable material.

[0052] The present invention also provides a preparation method of a high-frequency and high-voltage resistant wire and cable material, comprising the following steps:

[0053] Masterbatch processing: Polyethylene and the insulating and heat-conducting material are kneaded by a kneader according to the ratio, and then extruded, drawn into strips, and pelletized by an extrusion device to obtain masterbatch pellets;

[0054] Extruding wire: The obtained masterbatch pellets are extruded by an extrusion device to obtain semi-finished wire.

[0055] Irradiation process: The semi-finished wire is irradiated by an irradiation device to obtain a high-frequency and high-voltage resistant wire and cable material.

[0056] In some embodiments, in the masterbatch processing step, when polyethylene and the insulating and heat-conducting material are kneaded, a polyolefin elastomer, a compatibilizer, an antioxidant, a coupling agent or a sensitizer can also be added for kneading.

[0057] In some embodiments, in the masterbatch processing step, the kneading temperature of the kneader is 100 - 130 °C, and the kneading time is 10 - 20 min.

[0058] In some embodiments, in the masterbatch processing step, the extrusion temperature of the extrusion device is 130 - 190 °C.

[0059] In some embodiments, in the extruding wire step, the extrusion temperature of the extrusion device is 130 - 190 °C.

[0060] In some embodiments, in the irradiation process step, the irradiation dose of the irradiation device is 60 - 200 KGy.

[0061] The high-frequency and high-voltage resistant wire and cable material of the present invention can be used to manufacture both the insulating layer and the sheath of wire and cable, and both meet the safety requirements of the national standard GB9706.202 - 2021.

[0062] The technical solution of the present invention will be further described in detail below in conjunction with specific embodiments. It should be understood that the following specific embodiments are only used to explain the present invention and are not used to limit the present invention.

[0063] Measurement of high-frequency and high-voltage resistance

[0064] Test is carried out using a medical high-frequency dielectric strength tester, model: CS9706TY, manufacturer: Changsheng Instrument Intelligent Technology (Hangzhou) Co., Ltd. The measurement of high-frequency and high-voltage resistance is carried out according to the standard requirements of GB9706.202-2021. The passing standard for the measurement is: at a frequency of 400±100kHz, a voltage of 5000V, and after a withstand voltage of 60s, the leakage current does not exceed 100mA.

[0065] Measurement of thermal conductivity

[0066] It is measured according to the measurement method of ASTM D5470.

[0067] Measurement of volume resistivity

[0068] It is measured according to the measurement method of the attached drawing of UL224.

[0069] Measurement of mechanical properties

[0070] Tensile strength and elongation at break are measured according to the measurement method of UL224.

[0071] Example 1

[0072] Masterbatch processing

[0073] Low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 is added to a kneader for kneading. The kneading temperature is 100-130°C, and the kneading time is 15 min. The material obtained from the above process is put into a twin-screw extruder with a diameter of 30 mm and extruded at a screw speed of 45 rpm and a temperature of 130-190°C, followed by strand drawing, water cooling and pelletizing to finally form masterbatch particles.

[0074] Extrusion of wire

[0075] The masterbatch particles obtained above are used for wire extrusion with the aid of a single-screw wire extruder. A full-thread screw is used, and extrusion molding is carried out at a screw speed of 5-45 rpm and a die temperature of 130-190°C to obtain semi-finished wire.

[0076] Irradiation crosslinking

[0077] The above semi-finished wire materials are irradiated by an electron accelerator device with an irradiation dose of 180 KGy for irradiation crosslinking to obtain high-frequency and high-voltage resistant wire and cable materials.

[0078] Example 2

[0079] Masterbatch processing

[0080] Except that low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was replaced with linear low-density polyethylene (LLDPE, LLDPE 218W) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4, the manufacturing was carried out in the same manner as in Example 1.

[0081] Extrusion of wire

[0082] The semi-forming was carried out in the same manner as in Example 1.

[0083] Irradiation crosslinking

[0084] The irradiation was carried out in the same manner as in Example 1 to obtain high-frequency and high-voltage resistant wire and cable materials.

[0085] Example 3

[0086] Masterbatch processing

[0087] Except that low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was replaced with medium-density polyethylene (MDPE, DOW AXELERON TM 8864NT) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4, the manufacturing was carried out in the same manner as in Example 1.

[0088] Extrusion of wire

[0089] The semi-forming was carried out in the same manner as in Example 1.

[0090] Irradiation crosslinking

[0091] The irradiation was carried out in the same manner as in Example 1 to obtain high-frequency and high-voltage resistant wire and cable materials.

[0092] Example 4

[0093] Masterbatch processing

[0094] Except that the low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was replaced with high-density polyethylene (HDPE, lyondellbasell ACP6541A) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4, the manufacturing was carried out in the same manner as in Example 1.

[0095] Extruded wire

[0096] Semi-forming was carried out in the same manner as in Example 1.

[0097] Irradiation crosslinking

[0098] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0099] Example 5

[0100] Masterbatch processing

[0101] Except that α-Al2O3 (4μm) was replaced with α-Al2O3 (1μm), the manufacturing was carried out in the same manner as in Example 1.

[0102] Extruded wire

[0103] Semi-forming was carried out in the same manner as in Example 1.

[0104] Irradiation crosslinking

[0105] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0106] Example 6

[0107] Masterbatch processing

[0108] Except that α-Al2O3 (4μm) was replaced with α-Al2O3 (7μm), the manufacturing was carried out in the same manner as in Example 1.

[0109] Extruded wire

[0110] Semi-forming was carried out in the same manner as in Example 1.

[0111] Irradiation crosslinking

[0112] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0113] Example 7

[0114] Masterbatch processing

[0115] Manufacturing was carried out in the same manner as in Example 1, except that α-Al2O3 (4 μm) was replaced with α-Al2O3 (10 μm).

[0116] Extruded wire

[0117] Semi-forming was carried out in the same manner as in Example 1.

[0118] Irradiation crosslinking

[0119] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0120] Example 8

[0121] Masterbatch processing

[0122] Manufacturing was carried out in the same manner as in Example 1, except that the mass ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) = 30 / 25 / 0.4 was replaced with the mass ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / boron nitride (4 μm) / antioxidant (antioxidant 1010) = 30 / 25 / 0.4.

[0123] Extruded wire

[0124] Semi-forming was carried out in the same manner as in Example 1.

[0125] Irradiation crosslinking

[0126] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0127] Example 9

[0128] Masterbatch processing

[0129] Manufacturing was carried out in the same manner as in Example 1, except that the mass ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) = 30 / 25 / 0.4 was replaced with the mass ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / aluminum nitride (4 μm) / antioxidant (antioxidant 1010) = 30 / 25 / 0.4.

[0130] Extruded wire

[0131] Semi-forming was carried out in the same manner as in Example 1.

[0132] Irradiation crosslinking

[0133] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0134] Example 10

[0135] Masterbatch processing

[0136] Manufacture was carried out in the same manner as in Example 1, except that the ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was changed to (mass ratio) = 30 / 35 / 0.4.

[0137] Extrusion of wire

[0138] Semi-forming was carried out in the same manner as in Example 1.

[0139] Irradiation crosslinking

[0140] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0141] Example 11

[0142] Masterbatch processing

[0143] Manufacture was carried out in the same manner as in Example 1, except that the ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was changed to low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) (mass ratio) (mass ratio) = 30 / 50 / 0.4.

[0144] Extrusion of wire

[0145] Semi-forming was carried out in the same manner as in Example 1.

[0146] Irradiation crosslinking

[0147] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0148] Example 12

[0149] Masterbatch processing

[0150] It was manufactured in the same manner as in Example 1, except that the ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) (mass ratio) was changed from 30 / 25 / 0.4 to 40 / 25 / 0.4.

[0151] Extruded wire

[0152] Semi-forming was carried out in the same manner as in Example 1.

[0153] Irradiation crosslinking

[0154] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0155] Example 13

[0156] Masterbatch processing

[0157] It was manufactured in the same manner as in Example 1, except that the ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) (mass ratio) was changed from 30 / 25 / 0.4 to 50 / 25 / 0.4.

[0158] Extruded wire

[0159] Semi-forming was carried out in the same manner as in Example 1.

[0160] Irradiation crosslinking

[0161] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0162] Example 14

[0163] Masterbatch processing

[0164] It was manufactured in the same manner as in Example 1, except that the ratio of low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) (mass ratio) was changed from 30 / 25 / 0.4 to low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / metallocene-catalyzed ethylene and α-olefin copolymerized thermoplastic elastomer (POE, ENGAGE TM 8480) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 8 / 0.4.

[0165] Extruded wire

[0166] The semi-forming was carried out in the same manner as in Example 1.

[0167] Irradiation crosslinking

[0168] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0169] Example 15

[0170] Masterbatch processing

[0171] Except that the low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was replaced with low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / ethylene propylene diene monomer (EPDM, NORDEL TM 6530) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 8 / 0.4, the production was carried out in the same manner as in Example 1.

[0172] Extruding wire

[0173] The semi-forming was carried out in the same manner as in Example 1.

[0174] Irradiation crosslinking

[0175] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0176] Example 16

[0177] Masterbatch processing

[0178] Except that the low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was replaced with low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4μm) / ethylene propylene copolymer (EPM, Vistalon TM 785) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 8 / 0.4, the production was carried out in the same manner as in Example 1.

[0179] Extruding wire

[0180] The semi-forming was carried out in the same manner as in Example 1.

[0181] Irradiation crosslinking

[0182] Irradiation was carried out in the same manner as in Example 1 to obtain a high-frequency and high-voltage resistant wire and cable material.

[0183] Comparative Example 1

[0184] Masterbatch processing

[0185] Low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 0.4 was added to a kneader for kneading. The kneading temperature was 100 - 130 °C, and the kneading time was 15 min. The material obtained from the above process was put into a twin-screw extruder with a diameter of 30 mm and extruded at a screw rotation speed of 45 rpm and a temperature of 130 - 190 °C, followed by strand drawing, water cooling and pelletizing to finally form masterbatch pellets.

[0186] Extruding wire

[0187] The masterbatch pellets obtained above were used to extrude wire by means of a wire extruder. A full-thread screw was used, and extrusion molding was carried out at a screw rotation speed of 5 - 45 rpm and a die temperature of 130 - 190 °C to obtain semi-finished wire.

[0188] Irradiation crosslinking

[0189] The above semi-finished wire was irradiated using an electron accelerator device and irradiated and crosslinked at an irradiation dose of 180 KGy to obtain a wire and cable material.

[0190] Comparative Example 2

[0191] Masterbatch processing

[0192] Except that low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4 was replaced with low-density polyethylene (LDPE, lyondellbasell Lupolen 2426K) / α-Al2O3 (20 μm) / antioxidant (antioxidant 1010) (mass ratio) = 30 / 25 / 0.4, the manufacturing was carried out in the same manner as in Example 1.

[0193] Extruding wire

[0194] Semi-forming was carried out in the same manner as in Example 1.

[0195] Irradiation crosslinking

[0196] Irradiation was carried out in the same manner as in Example 1 to obtain a wire and cable material.

[0197] Comparative Example 3

[0198] Masterbatch processing

[0199] It was manufactured in the same manner as in Example 1, except that the ratio of low-density polyethylene (LDPE, LyondellBasell Lupolen 2426K) / α-Al2O3 (4 μm) / antioxidant (antioxidant 1010) was changed from (mass ratio) = 30 / 25 / 0.4 to (mass ratio) = 30 / 10 / 0.4.

[0200] Extruding wire

[0201] Semi-forming was carried out in the same manner as in Example 1.

[0202] Irradiation crosslinking

[0203] Irradiation was carried out in the same manner as in Example 1 to obtain wire and cable materials.

[0204] Comparative Example 4

[0205] Masterbatch processing

[0206] It was manufactured in the same manner as in Example 1.

[0207] Extruding wire

[0208] Extrusion was carried out in the same manner as in Example 1 to obtain wire and cable materials.

[0209] Comparative Example 5

[0210] A commercially available PTFE wire and cable of AWG8 model was used.

[0211] When the amount of the insulating and heat-conducting material is too high, although wire can be extruded, its physical properties such as tensile strength and elongation at break decrease, and it can no longer meet the basic requirements of the wire and cable. Appropriate amounts of POE, EPDM, EPM, etc. can be added to improve the corresponding physical properties to meet the usage requirements of the wire and cable.

[0212] For the high-frequency and high-voltage resistant wire and cable materials prepared above, the preparation condition parameters of Examples 1-16 are shown in Table 1, and the preparation condition parameters of Comparative Examples 1-5 are shown in Table 2. The high-frequency and high-voltage resistance performance of the prepared wire and cable materials was measured according to the above-mentioned measurement method for high-frequency and high-voltage resistance; the thermal conductivity of the prepared wire and cable materials was measured according to the above-mentioned measurement method for thermal conductivity; the volume resistivity of the prepared wire and cable materials was measured according to the above-mentioned measurement method for volume resistivity; the tensile strength and elongation at break of the prepared wire and cable materials were measured according to the above-mentioned measurement method for mechanical properties. The measurement results of Examples 1-16 and Comparative Examples 1-5 are shown in Table 3.

[0213] Table 1 Preparation condition parameters of Examples 1-16

[0214]

[0215]

[0216] Table 2 Preparation condition parameters of Comparative Examples 1-5

[0217]

[0218] Table 3 Measurement results of Examples 1-16 and Comparative Examples 1-5

[0219]

[0220]

[0221] From Examples 1-16 and Comparative Example 1, it can be seen that the wire and cable material prepared from polyethylene and the insulating and heat-conducting material has a good thermal conductivity, resulting in a small temperature rise of the wire and cable material under high frequency and high voltage. It realizes that at a frequency of 400±100 kHz, a voltage of 5000 V, and after withstanding voltage for 60 s, the leakage current does not exceed 100 mA, meeting the safety requirement performance of GB9706.202-2021. From Examples 1, 14-16, it can be seen that after adding the polyolefin elastomer, the mechanical properties of the wire and cable material are improved. From Examples 1 and Comparative Example 4, it can be seen that the high-frequency and high-voltage resistant wire and cable material must be irradiated and crosslinked, otherwise the performance in terms of thermal conductivity, mechanical properties, volume resistivity, etc. will all decline. In summary, the high-frequency and high-voltage resistant wire and cable material provided by the present invention has good mechanical properties, is resistant to high frequency and high voltage at the same time, and has a broad application prospect, especially suitable for the manufacture of various wires and cables in the high-frequency and high-voltage fields.

[0222] The above are only the preferred embodiments of the present invention, and thus do not limit the patent scope of the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the patent protection scope of the present invention.

Claims

1. A high-frequency and high-voltage resistant wire and cable material, characterized in that, Calculated by weight parts, the preparation materials of the high-frequency and high-voltage resistant wire and cable material include the following components: Polyethylene: 30 - 50 parts; Insulating and heat-conducting material: 25 - 50 parts.

2. The high-frequency and high-voltage resistant wire and cable compound according to claim 1, wherein, The tensile strength of the polyethylene is greater than 17 Mpa.

3. The high-frequency and high-voltage resistant wire and cable material according to claim 1, characterized in that, The insulating and heat-conducting material includes at least one of α-Al2O3, boron nitride, and aluminum nitride.

4. The high-frequency and high-voltage resistant wire and cable material according to claim 1, characterized in that The average particle size of the insulating and heat-conducting material is 1 - 10 μm.

5. The high-frequency and high-voltage resistant wire and cable material according to claim 1, characterized in that The average particle size of the insulating and heat-conducting material is 4 - 7 μm.

6. The high-frequency and high-voltage resistant wire and cable material according to claim 1, characterized in that, The preparation materials of the high-frequency and high-voltage resistant wire and cable material further include polyolefin elastomer: 5 - 10 parts, and the polyolefin elastomer includes at least one of thermoplastic elastomer polymerized by metallocene-catalyzed ethylene and α-olefin, ethylene propylene diene monomer (EPDM), and ethylene propylene copolymer (EPM).

7. The high-frequency and high-voltage resistant wire and cable material according to claim 1, characterized in that The preparation materials of the high-frequency and high-voltage resistant wire and cable material further include compatibilizer: 1 - 5 parts, and the compatibilizer includes at least one of polyolefin elastomer graft and polyethylene graft.

8. The high-frequency and high-voltage resistant wire and cable material according to claim 1, characterized in that The preparation materials of the high-frequency and high-voltage resistant wire and cable material further include antioxidant 0.3 - 0.5 parts, and the antioxidant includes at least one of hindered phenol main antioxidant and thioether antioxidant; Or, the preparation materials of the high-frequency and high-voltage resistant wire and cable material further include coupling agent 0.3 - 1 part, and the coupling agent includes at least one of aluminate coupling agent and titanate coupling agent; Or, the preparation materials of the high-frequency and high-voltage resistant wire and cable material further include sensitizer 0.3 - 1 part, and the sensitizer includes at least one of trimethylolpropane tri(meth)acrylate, trimethylolpropane triacrylate, pentaerythritol tetraacrylate, triallyl isocyanate, or 1,3-butanediol dimethacrylate.

9. A preparation method of a high-frequency and high-voltage resistant wire and cable material, characterized in that, Including the following steps: Masterbatch processing: Mix polyethylene and insulating and heat-conducting material according to the ratio through an internal mixer, and then extrude, draw into strips, and pelletize through an extrusion device to obtain masterbatch particles; Extruding wire: Extrude the masterbatch particles obtained above through an extrusion device to obtain semi-finished wire. Irradiation process: Irradiate the above semi-finished wire through an irradiation device to obtain the high-frequency and high-voltage resistant wire and cable material.

10. The preparation method according to claim 9, characterized in that, In the masterbatch processing step, when mixing polyethylene and insulating and heat-conducting material, polyolefin elastomer, compatibilizer, antioxidant, coupling agent, or sensitizer can also be added for mixing; Or, in the masterbatch processing step, the mixing temperature of the internal mixer is 100 - 130 °C, and the mixing time is 10 - 20 min; Or, in the masterbatch processing step, the extrusion temperature of the extrusion device is 130 - 190 °C; Or, in the extruding wire step, the extrusion temperature of the extrusion device is 130 - 190 °C; Or, in the irradiation process step, the irradiation dose of the irradiation device is 60 - 200 KGy.

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