Environment-friendly peelable semiconductive shielding material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of polymers, and discloses an environment-friendly peelable semiconductive shielding material and a preparation method and application thereof, the semiconductive shielding material contains a functional monomer graft modified propylene polymer, an ethylene copolymer, a conductive filler and an antioxidant; based on the total weight of the functional monomer graft modified propylene polymer, the ethylene copolymer and the conductive filler, the content of the functional monomer graft modified propylene polymer is 5-60 wt%, the content of the ethylene copolymer is 15-75 wt%, and the content of the conductive filler is 15-45 wt%; by taking the weight of the functional monomer graft-modified propylene polymer as a reference, the content of a grafted functional monomer structural unit in the functional monomer graft-modified propylene polymer is 5-30wt%. The semi-conductive shielding material disclosed by the invention has good mechanical property and excellent conductivity, is peelable, and can be matched with a polypropylene-based insulating material for use.

Description

Technical Field

[0001] This invention belongs to the field of polymer technology, specifically relating to an environmentally friendly peelable semiconductive shielding material, a method for preparing the semiconductive shielding material, and applications of the semiconductive shielding material. Background Technology

[0002] With the sustained and rapid development of my country's economy and the continuous improvement of people's living standards, the demand for electricity is also growing rapidly. Solving the problem of power transmission channels, and delivering large-capacity electrical energy to users, is one of the major issues that urgently needs to be addressed in power development. To address this problem, my country has established the basic development direction of constructing and developing ultra-high voltage and large-capacity AC / DC transmission systems.

[0003] Traditional extruded cables typically use cross-linked polyethylene (XLPE) as the cable insulation material. However, this has revealed several problems during production and operation: the maximum operating temperature of these cables can reach 90°C, but the maximum operating temperature of existing XLPE cables is only 70°C; the cross-linking process generates byproducts, increasing the probability of cable breakdown.

[0004] Power cables are mainly composed of metallic conductors, conductor shielding layers, insulation layers, insulation shielding layers, and protective materials. To meet the requirements of environmental protection and sustainable development, research on novel recyclable non-crosslinked polyolefin cable insulation materials has become a hot topic in insulation materials. Polypropylene, with its excellent motor performance and low price, has become the most popular research direction. Research on environmentally friendly semi-conductive shielding materials compatible with polypropylene insulation materials is also of great significance. Currently, there are few reports on environmentally friendly semi-conductive shielding materials, especially peelable semi-conductive shielding materials, both domestically and internationally. To adapt to the application trend of high current carrying capacity cables and the convenience of installation, developing a peelable, non-crosslinked environmentally friendly semi-conductive shielding material with good mechanical properties, stable conductivity, and high practical value is essential. Summary of the Invention

[0005] To address the aforementioned problems in existing technologies, the purpose of this invention is to provide an environmentally friendly peelable semiconductive shielding material, its preparation method, and its applications. This semiconductive shielding material possesses good mechanical properties, excellent electrical conductivity, and is peelable.

[0006] A first aspect of the present invention provides an environmentally friendly peelable semiconductive shielding material comprising a functional monomer-grafted modified propylene polymer, an ethylene copolymer, a conductive filler, and an antioxidant.

[0007] Based on the total weight of the functional monomer grafted modified propylene polymer, ethylene copolymer, and conductive filler, the content of the functional monomer grafted modified propylene polymer is 5-60 wt%, the content of the ethylene copolymer is 15-75 wt%, and the content of the conductive filler is 15-45 wt%; based on the weight of the functional monomer grafted modified propylene polymer, the content of the functional monomer structural units in the grafted state in the functional monomer grafted modified propylene polymer is 5-30 wt%.

[0008] A second aspect of the present invention provides a method for preparing the above-mentioned environmentally friendly peelable semiconductive shielding material, the method comprising the following steps:

[0009] S1: In the presence of an inert gas, a reaction mixture including a propylene polymer and a functional monomer is subjected to a grafting reaction to obtain a propylene polymer grafted with a functional monomer.

[0010] S2: Mix the materials containing the functional monomer-grafted modified propylene polymer, ethylene copolymer, conductive filler and antioxidant, melt extrude and granulate to obtain the semi-conductive shielding material.

[0011] A third aspect of the present invention provides the application of the above-mentioned environmentally friendly peelable semiconductive shielding material in the field of cable semiconductive shielding.

[0012] Compared with the prior art, the present invention has the following beneficial effects:

[0013] The semiconductive shielding material of the present invention has good mechanical properties, excellent and stable conductivity, and peelability; the semiconductive shielding material of the present invention is non-crosslinked, green and environmentally friendly, and can be used in conjunction with polypropylene-based insulating materials.

[0014] Other features and advantages of the present invention will be described in detail in the following detailed description section. Detailed Implementation

[0015] The following provides a detailed description of specific embodiments of the present invention. It should be understood that the specific embodiments described herein are for illustrative and explanatory purposes only and are not intended to limit the scope of the invention.

[0016] According to a first aspect of the present invention, the present invention provides an environmentally friendly peelable semiconductive shielding material comprising a functional monomer-grafted modified propylene polymer, an ethylene copolymer, a conductive filler, and an antioxidant.

[0017] Based on the total weight of the functional monomer grafted modified propylene polymer, ethylene copolymer, and conductive filler, the content of the functional monomer grafted modified propylene polymer is 5-60 wt%, the content of the ethylene copolymer is 15-75 wt%, and the content of the conductive filler is 15-45 wt%; based on the weight of the functional monomer grafted modified propylene polymer, the content of the functional monomer structural units in the grafted state in the functional monomer grafted modified propylene polymer is 5-30 wt%.

[0018] In a preferred embodiment, based on the total weight of the functional monomer-grafted modified propylene polymer, ethylene copolymer, and conductive filler, the content of the functional monomer-grafted modified propylene polymer is 8-55 wt%, preferably 10-45 wt%, the content of the ethylene copolymer is 25-65 wt%, preferably 28-58 wt%, and the content of the conductive filler is 18-35 wt%; and based on the weight of the functional monomer-grafted modified propylene polymer, the content of the functional monomer structural units in the grafted state in the functional monomer-grafted modified propylene polymer is 10-25 wt%.

[0019] In this invention, the semiconductive shielding material has at least one of the following characteristics: a melt flow rate of 0.01-8 g / 10 min, more preferably 0.01-4 g / 10 min, at 230°C and a load of 2.16 kg; a melting temperature Tm of 110-180°C, more preferably 120-170°C; and a density of 0.900-1.100 g / cm³. 3 .

[0020] According to the present invention, the volume resistivity of the semiconductive shielding material at 20°C is not greater than 40 Ω·cm, preferably not greater than 30 Ω·cm; and at 105°C, the volume resistivity is not greater than 200 Ω·cm, preferably not greater than 120 Ω·cm; the peel force between the semiconductive shielding material and the insulating layer is not greater than 40 N / cm, preferably not greater than 20 N / cm; the tensile strength of the semiconductive shielding material is 5-30 MPa, preferably 10-25 MPa; and the elongation at break is 50-800%, preferably 100-600%.

[0021] The functional monomers of the present invention contain alkenyl groups, which can be grafted onto propylene polymers. Therefore, any alkenyl-containing functional monomers with alkenyl groups located in reactive positions are applicable to the present invention.

[0022] Specifically, the functional monomer may be selected from at least one of the monomers having the structure shown in formula (1).

[0023]

[0024] In equation (1), Rb R c R d Each is independently selected from H, substituted or unsubstituted alkyl groups; R a It is selected from substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted ester, substituted or unsubstituted carboxyl, substituted or unsubstituted cycloalkyl or heterocyclic, cyano, substituted or unsubstituted silyl.

[0025] Preferably, R b R c R d Each is independently selected from H, substituted or unsubstituted C1-C6 alkyl groups; R a Selected from substituted or unsubstituted C1-C 20 Alkyl, substituted or unsubstituted C1-C 20 Alkoxy, substituted or unsubstituted C6-C 20 aryl, substituted or unsubstituted C1-C 20 Ester group, substituted or unsubstituted C1-C 20 Carboxyl, substituted or unsubstituted C3-C 20 Cycloalkyl or heterocyclic, cyano, substituted or unsubstituted C3-C 20 Silyl group; the substituted group is halogen, hydroxyl, amino, C1-C 12 Alkyl, C3-C6 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 Acyloxy group.

[0026] More preferably, R b R c R d Each is independently selected from H, substituted or unsubstituted C1-C6 alkyl groups; R a Selected from the group shown in formula (2), the group shown in formula (3), the group shown in formula (4), the group shown in formula (5), the group shown in formula (6), a combination of the group shown in formula (6) and the group shown in formula (7), and heterocyclic groups.

[0027]

[0028] In equation (2), R 4 -R 8 Each is independently selected from H, halogen, hydroxyl, amino, phosphate group, sulfonic acid group, substituted or unsubstituted C1-C. 12 Alkyl, substituted or unsubstituted C3-C 12 cycloalkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C l -C 12ester group, substituted or unsubstituted C1-C 12 The substituted amino group, wherein the substituted group is selected from halogen, hydroxyl, amino, phosphate, sulfonic acid, C1-C 12 Alkyl, C3-C 12 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 ester group, C1-C 12 The amino group; preferably, R 4 -R 8 Each is independently selected from H, halogen, hydroxyl, amino, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C6 alkoxy.

[0029]

[0030] In equation (3), R4-R 10 Each is independently selected from H, halogen, hydroxyl, amino, phosphate group, sulfonic acid group, substituted or unsubstituted C1-C. 12 Alkyl, substituted or unsubstituted C3-C 12 cycloalkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C1-C 12 ester group, substituted or unsubstituted C1-C 12 The substituted amino group, wherein the substituted group is selected from halogen, hydroxyl, amino, phosphate, sulfonic acid, C1-C 12 Alkyl, C3-C 12 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 ester group, C1-e 12 The amino group; preferably, R4-R 10 Each of the groups is independently selected from H, halogen, hydroxyl, amino, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C6 alkoxy, wherein the substituted group is selected from halogen, hydroxyl, amino, C1-C6 alkyl, C1-C6 alkoxy.

[0031]

[0032] In equation (4), R4'-R 10 Each group is independently selected from H, halogen, hydroxyl, amino, phosphate, sulfonic acid, substituted or unsubstituted C1-C. 12 Alkyl, substituted or unsubstituted C3-C 12 cycloalkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C1-C 12 ester group, substituted or unsubstituted C1-C 12The substituted amino group, wherein the substituted group is selected from halogen, hydroxyl, amino, phosphate, sulfonic acid, C1-C 12 Alkyl, C3-C 12 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 ester group, C1-C 12 The amino group; preferably, R4'-R 10 Each of the groups is independently selected from H, halogen, hydroxyl, amino, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C6 alkoxy, wherein the substituted group is selected from halogen, hydroxyl, amino, C1-C6 alkyl, C1-C6 alkoxy.

[0033]

[0034] In equation (5), R', R”, and R”' are each independently selected from substituted or unsubstituted C1-C. 12 Straight-chain alkyl, substituted or unsubstituted C3-C 12 Branched alkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C1-C 12 The acyloxy group; preferably, R', R'', R''' are each independently selected from substituted or unsubstituted C1-C6 straight-chain alkyl groups, substituted or unsubstituted C3-C6 branched alkyl groups, substituted or unsubstituted C1-C6 alkoxy groups, and substituted or unsubstituted C1-C6 acyloxy groups.

[0035]

[0036] In equation (6), R m Selected from the following groups, substituted or unsubstituted: C1-C 20 Straight-chain alkyl, C3-C 20 Branched alkyl, C3-C 12 cycloalkyl, C3-C 12 Epoxyalkyl, C3-C 12 Epoxyalkyl alkyl, wherein the substituted group is selected from at least one of halogen, amino, and hydroxyl groups. Wherein C3-C 12 Epoxyalkyl refers to an alkyl group that has 3-12 carbon atoms and is substituted with an epoxyalkyl group, such as ethylene oxide methyl.

[0037] The heterocyclic group can be selected from imidazole, pyrazol, carbazole, pyrrolidone, pyridinyl, piperidinyl, caprolactam, pyrazinyl, thiazolyl, purine, morpholino, and oxazolino.

[0038] In this invention, the functional monomer can be selected from aromatic olefin monomers, alkenyl-containing silane monomers, acrylate monomers, and optionally acrylic monomers, preferably acrylate monomers and optionally acrylic monomers.

[0039] Specifically, the aromatic olefin monomer may be selected from at least one of styrene, α-methylstyrene, 1-vinylnaphthalene, 2-vinylnaphthalene, monosubstituted or polysubstituted styrene, monosubstituted or polysubstituted α-methylstyrene, monosubstituted or polysubstituted 1-vinylnaphthalene, and monosubstituted or polysubstituted 2-vinylnaphthalene. The substituted group is preferably selected from at least one of halogen, hydroxyl, amino, phosphate, sulfonic acid, C1-C8 straight-chain alkyl, C3-C8 branched alkyl or cycloalkyl, C1-C6 straight-chain alkoxy, C3-C8 branched alkoxy or cyclic alkoxy, C1-C8 straight-chain ester, C3-C8 branched ester or cyclic ester, C1-C8 straight-chain amino, and C3-C8 branched amino or cyclic amino; more preferably, the aromatic olefin monomer is selected from at least one of styrene, α-methylstyrene, 2-methylstyrene, 3-methylstyrene, and 4-methylstyrene.

[0040] The alkenyl-containing silane monomer may be selected from at least one of vinyltriethoxysilane, vinyltrimethoxysilane, vinyltriisopropoxysilane, vinyltritert-butoxysilane, vinyltriacetoxysilane, methylvinyldimethoxysilane, ethylvinyldiethoxysilane, allyltriethoxysilane, allyltrimethoxysilane, allyltriisopropoxysilane, vinyltri(β-methoxyethoxy)silane, allyltri(β-methoxyethoxy)silane, allyltritert-butoxysilane, allyltriacetoxysilane, methylallyldimethoxysilane, and ethylallyldiethoxysilane.

[0041] The acrylate monomers may be selected from at least one of methyl methacrylate, sec-butyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, isooctyl methacrylate, dodecyl methacrylate, coconut oil ester methacrylate, octadecyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, and glycidyl methacrylate.

[0042] The acrylic monomer may be selected from at least one of acrylic acid, methacrylic acid and 2-ethylacrylic acid.

[0043] In this invention, the structural units derived from acrylic monomers may be absent or may coexist with the structural units derived from acrylate monomers. When the functional monomer is an acrylate monomer or optionally an acrylic monomer, the molar ratio of the structural units derived from acrylate monomers to the structural units derived from acrylic monomers may be 1:0-2, preferably 1:0.125-1.

[0044] According to the present invention, the functional monomer can be an alkenyl-containing heterocyclic compound, which can be any alkenyl-containing heterocyclic compound capable of free radical polymerization, and can be selected from at least one of alkenyl-substituted imidazole, alkenyl-substituted pyrazole, alkenyl-substituted carbazole, alkenyl-substituted pyrrolidone, alkenyl-substituted pyridine or pyridine salt, alkenyl-substituted piperidine, alkenyl-substituted caprolactam, alkenyl-substituted pyrazine, alkenyl-substituted thiazole, alkenyl-substituted purine, alkenyl-substituted morpholine, and alkenyl-substituted oxazoline; preferably, the alkenyl-containing heterocyclic monomer is a monoalkenyl-containing heterocyclic monomer.

[0045] Specifically, the alkenyl-containing heterocyclic monomer may be selected from at least one of the following: 1-vinylimidazolium, 2-methyl-1-vinylimidazolium, N-allylimidazolium, 1-vinylpyrazole, 3-methyl-1-vinylpyrazole, vinylcarbazole, N-vinylpyrrolidone, 2-vinylpyridine, 3-vinylpyridine, 4-vinylpyridine, 2-methyl-5-vinylpyridine, vinylpyridine N-oxide, vinylpyridine salt, vinylpiperidine, N-vinylcaprolactam, 2-vinylpyrazine, N-vinylpiperazine, 4-methyl-5-vinylthiazole, N-vinylpurine, vinylmorpholine, and vinyloxazoline.

[0046] In this invention, the term "structural unit" refers to a part of a propylene polymer grafted with a functional monomer, and its form is not limited. Specifically, "functional monomer structural unit" and "structural unit derived from functional monomer" refer to products formed from functional monomers, which include products in the form of "groups," "monomers," and "polymers"; "structural unit derived from propylene polymer" refers to products formed from propylene polymers, which include products in the form of "groups" and "polymers." The "structural unit" can be a repeating unit or a non-repeating independent unit.

[0047] According to the present invention, the propylene polymer modified by the functional monomer grafting includes structural units derived from propylene polymers and structural units derived from functional monomers; the functional monomer structural units in the grafted state are structural units derived from functional monomers and in the grafted state.

[0048] In this invention, the propylene polymer can be homopolymer or copolymer polypropylene, and the propylene polymer has at least one of the following characteristics: a comonomer content of 0-15 mol%, preferably 0-12 mol%, more preferably 0-8 mol%; a melt flow rate of 0.01-10 g / 10 min at 230°C and 2.16 kg load, preferably 0.1-5 g / 10 min; a melt temperature Tm of 110-180°C, more preferably 120-170°C; and a weight-average molecular weight of 20 × 10⁻⁶. 4 -50×10 4 g / mol; tensile strength greater than 5 MPa, preferably 10-40 MPa.

[0049] According to the present invention, the comonomer of the copolymerized polypropylene may be selected from at least one of C2-C8 α-olefins other than propylene. Preferably, the comonomer of the copolymerized polypropylene is selected from at least one of ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene, and 1-octene. More preferably, the comonomer of the copolymerized polypropylene is ethylene and / or 1-butene. The copolymerized polypropylene of the present invention is preferably a porous granular or powdered resin.

[0050] The homopolymer or copolymer polypropylene described in this invention can be any commercially available polypropylene powder suitable for this invention, or it can be produced by the polymerization process described in patent documents CN102453180B, CN101490096B, CN102816269B, CN102816270B, etc.

[0051] According to the present invention, the concept of "ethylene copolymer" is well known to those skilled in the art, referring to a non-crosslinked polyolefin material copolymerized from ethylene and a polar monomer. The polar copolymer unit, i.e., the polar monomer, can be acrylic acid, methacrylic acid, acrylate, methacrylate, vinyl ester, preferably acrylic acid or vinyl ester. The ethylene copolymer can be any commercially available powder or granule suitable for the present invention, such as at least one of ethylene vinyl acetate (EVA) and ethylene acrylate (EAA). This includes, but is not limited to, DuPont's NUCREL series and ExxonMobile's ESCOR series. It can also be prepared by the methods described in patents or documents such as CN101490096A and CN112724303A.

[0052] Preferably, the ethylene copolymer has at least one of the following characteristics: a polar comonomer content of 0-40 mol%, preferably 10-35 mol%; a melt flow rate of 0.05-25 g / 10 min at 190°C and 2.16 kg load, preferably 1-10 g / 10 min; a melt temperature greater than 40°C, preferably 50°C-140°C; a tensile strength greater than 10 MPa; and an elongation at break greater than 500%.

[0053] In this invention, the conductive filler may be selected from one or more of conductive carbon black, carbon nanotubes, graphene, and MXene, preferably conductive carbon black, and more preferably acetylene black.

[0054] Preferably, the acetylene black has an oil absorption value of not less than 120cc / 100g, an iodine absorption value of not less than 70mg / g, and a residue of not more than 25ppm on a 325-mesh sieve.

[0055] According to a second aspect of the present invention, the present invention provides a method for preparing the above-mentioned environmentally friendly peelable semiconductive shielding material, the method comprising the following steps:

[0056] S1: In the presence of an inert gas, a reaction mixture including a propylene polymer and a functional monomer is subjected to a grafting reaction to obtain a propylene polymer grafted with a functional monomer.

[0057] S2: Mix the materials containing the functional monomer-grafted modified propylene polymer, ethylene copolymer, conductive filler and antioxidant, melt extrude and granulate to obtain the semi-conductive shielding material.

[0058] According to one specific embodiment, the preparation method of the environmentally friendly peelable semiconductive shielding material includes the following steps:

[0059] a. Place the propylene polymer in a closed reactor and replace it with an inert gas;

[0060] b. Add the free radical initiator and functional monomer to the closed reactor and stir to mix;

[0061] c. Optionally add an interfacial agent and optionally swell the reaction system;

[0062] d. Optionally add a dispersant to raise the temperature of the reaction system to the grafting reaction temperature and carry out the grafting reaction;

[0063] f. Optionally, filter the product and place it in a vacuum or inert gas environment to heat and devolatilize it to obtain a functional monomer-grafted modified propylene polymer.

[0064] g. The propylene polymer and ethylene copolymer grafted with the functional monomers, conductive filler, antioxidant, and optional other additives are granulated by melt screw extrusion using a reciprocating single-screw compounding extruder or a twin-screw extruder to obtain the semi-conductive shielding material.

[0065] In this invention, the reaction mixture contains a free radical initiator, which may be selected from peroxide-based free radical initiators and / or azo-based free radical initiators. Preferably, the grafting site is initiated by a peroxide-based free radical initiator, and the grafting reaction is further carried out.

[0066] According to the present invention, the mass ratio of the free radical initiator to the functional monomer can be 0.01-10:100, preferably 0.5-5:100.

[0067] Specifically, the peroxide-based free radical initiator may be selected from at least one of benzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, lauroyl peroxide, dodecyl peroxide, tert-butyl peroxide, diisopropyl peroxide, tert-butyl peroxide (2-ethylhexanoate), and dicyclohexyl peroxide.

[0068] Furthermore, the grafting reaction of the present invention can also be carried out by the methods described in CN106543369A, CN104499281A, CN102108112A, CN109251270A, CN1884326A and CN101492517B.

[0069] The present invention does not particularly limit the process conditions for the grafting reaction. Preferably, the grafting reaction is a solid-phase grafting reaction. Specifically, the temperature of the grafting reaction is 30-130℃, preferably 60-120℃; the time is 0.5-10 hours, preferably 1-6 hours.

[0070] In this invention, the "reaction mixture" includes all materials added to the grafting reaction system. The materials can be added all at once or at different stages of the reaction.

[0071] The reaction mixture of the present invention includes a dispersant, preferably an aqueous solution of water or sodium chloride. The mass amount of the dispersant is preferably 50-300% of the mass of the propylene polymer.

[0072] The reaction mixture of the present invention includes an interface agent, which is an organic solvent that has a swelling effect on polyolefins. Preferably, it is at least one of the following organic solvents that have a swelling effect on propylene polymers: ether solvents, ketone solvents, aromatic solvents, and alkane solvents. More preferably, it is at least one of the following organic solvents: chlorobenzene, polychlorinated benzene, alkanes or cycloalkanes with more than 6 carbon atoms, benzene, C1-C4 alkyl-substituted benzene, C2-C6 aliphatic ethers, C3-C6 aliphatic ketones, and decahydronaphthalene. Further preferably, it is at least one of the following organic solvents: benzene, toluene, xylene, chlorobenzene, tetrahydrofuran, diethyl ether, acetone, hexane, cyclohexane, decahydronaphthalene, and heptane. The mass content of the interface agent is preferably 1-30% of the mass of the propylene polymer, and more preferably 10-25%.

[0073] The reaction mixture of the present invention may each independently include an organic solvent as a solvent for dissolving the solid free radical initiator. The organic solvent preferably includes at least one of C2-C5 alcohols, C2-C4 ethers, and C3-C5 ketones; more preferably, it includes at least one of C2-C4 alcohols, C2-C3 ethers, and C3-C5 ketones; and most preferably, it includes at least one of ethanol, diethyl ether, and acetone. The mass content of the organic solvent is preferably 1-35% of the mass of the propylene polymer.

[0074] According to the present invention, if volatile components are present in the system after the reaction, the method of the present invention preferably includes a step of removing the volatiles, which can be carried out by any conventional method, including vacuum extraction or the use of a stripping agent at the end of the grafting process. Suitable stripping agents include, but are not limited to, inert gases.

[0075] As described above, the "functional monomer-grafted modified propylene polymer" of the present invention includes both the product (crude product) directly obtained from the propylene polymer and the functional monomer through a grafting reaction, and the pure grafted modified propylene polymer obtained by further purifying the product. Therefore, the preparation method of the present invention may optionally include a step of purifying the crude product. The purification can be carried out using various methods conventional in the art, such as extraction.

[0076] This invention does not impose a particular limitation on the grafting efficiency of the grafting reaction, but a higher grafting efficiency is more advantageous for obtaining functional monomer-grafted modified propylene polymer materials with the desired properties through a one-step grafting reaction. Therefore, it is preferable to control the grafting efficiency of the grafting reaction to be 20-100%, and more preferably 25-90%. The concept of grafting efficiency is well known to those skilled in the art, referring to the amount of functional monomer grafted onto the polymer and the total amount of functional monomers added to the reaction feed.

[0077] The inert gas described in this invention can be any of the inert gases commonly used in the art, including but not limited to nitrogen and argon.

[0078] The antioxidants of the present invention are selected from one or more of hindered phenols, hindered amines, phosphites, and thiocyanates, preferably from pentaerythritol tetrakis[β-(3,5---tert-butyl-4-hydroxyphenyl)propionate], 2,2′-methylenebis(4-methyl-6-tert-butylphenol), 2,4,6-tris(3′,5′-di-tert-butyl-4′-hydroxybenzyl)trimethylbenzene, 2,2′-thiobis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], 2 One or more of the following: ',2-oxamido-bis-[ethyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)]propionate, β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate n-octadecyl alcohol, 1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 4,4'-thiobis(6-tert-butyl-3-methylphenol), triphenyl phosphite, tris[2,4-di-tert-butylphenyl]phosphite, and dilauryl thiodipropionate.

[0079] In this invention, the antioxidant content in the resin and conductive filler mixture is greater than 2000 ppm, preferably 3000-15000 ppm.

[0080] According to the present invention, the other additives may be any one or more of the following: voltage stabilizers, antioxidants, copper inhibitors, processing aids, stripping agents, etc. The types and amounts of additives used are conventional and known to those skilled in the art.

[0081] The processing aids are fluorinated compounds, polypropylene wax, polyethylene wax, fatty acid esters, mineral oil, etc., preferably polypropylene wax, fatty acid esters and mineral oil.

[0082] The copper-resistant agent is preferably one or more of N,N′-bis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyl]hydrazine, 2,2-oxamido-bis[ethyl-3-(3,5-di-tert-butyl-4-hydroxyphenyl)]propionic acid, and N-salicylamidophthalimide.

[0083] The stripping agent can be a polar polyolefin wax, a modified polysiloxane, etc.

[0084] In this invention, the amount of additive added can be 0.1-8% of the mass of the mixture of resin and conductive filler, preferably 0.2-5%.

[0085] According to the present invention, the melt extrusion temperature is 170-250°C, preferably 180-230°C, and more preferably 190-220°C.

[0086] According to a third aspect of the present invention, the present invention provides the application of the above-described environmentally friendly peelable semiconductive shielding material in the field of cable semiconductive shielding.

[0087] The substances and process parameters not limited in this invention can be selected according to existing technology, which is a conventional technical means in this field.

[0088] The present invention will be further described below with reference to embodiments. However, the invention is not limited to these embodiments.

[0089] In the following embodiments and comparative examples, the data were obtained using the following methods:

[0090] 1. Determination of comonomer content in propylene polymers:

[0091] The content of comonomers was determined by quantitative Fourier transform infrared (FTIR) spectroscopy. The correlation of the determined comonomer content was calibrated by quantitative nuclear magnetic resonance (NMR) spectroscopy. Based on quantitative... 13 The calibration method for the C-NMR spectrometer results was performed according to conventional methods in the art.

[0092] 2. Determination of melt flow rate (melt index, MFR):

[0093] According to the method specified in GB / T 3682-2018, using a CEAST 7026 melt indexer, the melt index of propylene polymers and semiconductive shielding materials was determined at 230℃ and 2.16kg load, and the melt index of ethylene copolymers was determined at 190℃ and 2.16kg load.

[0094] 3. Determination of melting temperature (melting point, Tm):

[0095] Differential scanning calorimetry (DSC) was used to analyze the melting and crystallization processes of the material. Specifically, under nitrogen protection, 5-10 mg of sample was heated from 20°C to 200°C using a three-stage temperature rise and fall measurement method. The change in heat flow reflected the melting and crystallization processes, and the melting temperature Tm was calculated.

[0096] 4. Grafting rate (GD) (the content of functional monomer structural units in the grafted state in propylene polymers modified with functional monomers):

[0097] 2-4g of the grafted product was placed in a Soxhlet extractor and extracted for 12 hours with an organic solvent (ethyl acetate for aromatic olefin monomers, acrylate monomers, and acid anhydrides; acetone for silane monomers) to remove unreacted monomers and their homopolymers, yielding a pure grafted product. The product was dried, weighed, and the grafting rate (GD) was calculated. The formula for calculating GD in this invention is as follows:

[0098]

[0099] In the above formulas, W0 is the mass of the propylene polymer; W1 is the mass of the grafted product before extraction; and W2 is the mass of the grafted product after extraction.

[0100] 5. Measurement of DC volume resistivity:

[0101] The determination shall be carried out in accordance with the method specified in GB / T 1410-2006.

[0102] 6. Determination of tensile strength:

[0103] The determination shall be carried out in accordance with the method specified in GB / T 1040.2-2006.

[0104] 7. Determination of elongation at break:

[0105] The determination shall be carried out in accordance with the method specified in GB / T 1040.2-2006.

[0106] 8. Peel strength measurement:

[0107] Peel force was tested using a peel tester with a 180° peel method.

[0108] The sources and properties of the raw materials used in the examples and comparative examples are described in Table 1.

[0109] Table 1

[0110]

[0111] Example 1

[0112] Weigh 2.0 kg of PP1 powder (after sieving to remove fine powder smaller than 40 mesh) and add it to a 10 L reactor equipped with a mechanical stirrer. Seal the reaction system and purge with nitrogen to remove oxygen. Add 5.8 g of tert-butyl peroxide (2-ethylhexanoate) and 389.5 g of acrylic acid, stir and mix for 30 minutes, add 2 kg of water as a dispersant, and allow to swell at 60 °C for 2 hours. Then raise the temperature to 90 °C and react for 4 hours. After the reaction is complete, cool the mixture, filter to remove the water dispersant, and vacuum dry at 70 °C for 10 hours to obtain the grafted polypropylene powder.

[0113] Polypropylene grafted powder, C28J6, carbon black VXC500, 3000ppm antioxidant 1010 / 168 (mass ratio 1:1), 0.15% copper inhibitor 1024, and 0.3% stripper 6252 were weighed according to a mass ratio of 30:40:30 (the amounts of antioxidant, copper inhibitor, and stripper are based on the total mass of polypropylene grafted powder, C28J6, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material C1. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0114] Example 2

[0115] 2.0 kg of PPH-F03D powder (after sieving to remove fine powder smaller than 40 mesh) was weighed and added to a 10 L reactor equipped with a mechanical stirrer. The reaction system was sealed, and nitrogen was used for purging to remove oxygen. 5.0 g of benzoyl peroxide and 327.8 g of vinyl acetate were added, and the mixture was stirred for 30 minutes. The mixture was then swollen at 45 °C for 1 hour, and the temperature was raised to 95 °C for 3 hours. After the reaction was completed, the mixture was cooled and dried under vacuum at 70 °C for 10 hours to obtain the polypropylene grafted powder.

[0116] Polypropylene grafted powder, C28J6, carbon black VXC500, 4000ppm antioxidant 1035, 0.15% copper inhibitor 1024, and 0.3% processing aid 5920 were weighed according to a mass ratio of 22:50:28 (the amounts of antioxidant, copper inhibitor, and processing aid are based on the total mass of polypropylene grafted powder, C28J6, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material C2. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0117] Example 3

[0118] Weigh 2.0 kg of PP2 powder (after sieving to remove fine powder smaller than 40 mesh) and add it to a 10 L reactor equipped with a mechanical stirrer. Seal the reaction system and purge with nitrogen to remove oxygen. Add 7.5 g of benzoyl peroxide and 501.5 g of vinyltriethoxysilane, stir and mix for 30 minutes, swell at 40 °C for 2 hours, then raise the temperature to 95 °C and react for 4 hours. After the reaction is complete, cool and dry under vacuum at 70 °C for 10 hours to obtain the polypropylene grafted powder.

[0119] Polypropylene grafted powder, C28J6, carbon black VXC500, 3000ppm antioxidant 1010 / 168 / 1076 (mass ratio 1:1:1), 0.15% copper inhibitor 1024, and 0.3% processing aid 5920 were weighed according to a mass ratio of 28:42:30 (the amounts of antioxidant, copper inhibitor, and processing aid are based on the total mass of polypropylene grafted powder, C28J6, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material C3. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0120] Example 4

[0121] 2.0 kg of K8003 powder (after sieving to remove fine powder smaller than 40 mesh) was weighed and added to a 10 L reactor equipped with a mechanical stirrer. The reaction system was sealed, and nitrogen was used for purging to remove oxygen. 5.5 g of tert-butyl peroxide (2-ethylhexanoate) and 346.0 g of methyl methacrylate were added, and the mixture was stirred and mixed for 30 minutes. 2 kg of water (dispersant) was added, and the mixture was allowed to swell at 55 °C for 2 hours. The temperature was then raised to 90 °C, and the reaction was continued for 4 hours. After the reaction was completed, the mixture was cooled, filtered to remove the water (dispersant), and vacuum dried at 70 °C for 10 hours to obtain the polypropylene grafted powder.

[0122] Polypropylene grafted powder, V6110MC, carbon black VXC500, 3000ppm antioxidant 1010 / 168 (mass ratio 1:1), 0.15% copper inhibitor 1024, and 0.3% release agent 6252 were weighed according to a mass ratio of 38:32:30 (the amounts of antioxidant, copper inhibitor, and release agent are based on the total mass of polypropylene grafted powder, V6110MC, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material C4. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0123] Example 5

[0124] Weigh 2.0 kg of K8003 powder (after sieving to remove fine powder smaller than 40 mesh) and add it to a 10L reactor equipped with a mechanical stirrer. Seal the reaction system and purge with nitrogen to remove oxygen. Add 6.3 g of tert-butyl peroxide (2-ethylhexanoate) and 423.0 g of methyl methacrylate, stir and mix for 30 minutes, add 2 kg of water as a dispersant, swell at 55℃ for 2 hours, then raise the temperature to 90℃ and react for 4 hours. After the reaction is complete, cool down, filter to remove the water dispersant, and vacuum dry at 70℃ for 10 hours to obtain polypropylene grafted powder.

[0125] Polypropylene grafted powder, V6110MC, carbon black VXC500, 3000ppm antioxidant 1010 / 168 (mass ratio 1:1), 0.15% copper inhibitor 1024, and 0.3% release agent 6252 were weighed according to a mass ratio of 46:24:30 (the amounts of antioxidant, copper inhibitor, and release agent are based on the total mass of polypropylene grafted powder, V6110MC, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material C5. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0126] Example 6

[0127] Weigh 2.0 kg of PP1 powder (after sieving to remove fine powder smaller than 40 mesh) and add it to a 10 L reactor equipped with a mechanical stirrer. Seal the reaction system and purge with nitrogen to remove oxygen. Add 3.5 g of tert-butyl peroxide (2-ethylhexanoate) and 236.5 g of acrylic acid, stir and mix for 30 minutes, add 2 kg of water as a dispersant, and allow to swell at 60 °C for 2 hours. Then raise the temperature to 90 °C and react for 4 hours. After the reaction is complete, cool the mixture, filter to remove the water dispersant, and vacuum dry at 70 °C for 10 hours to obtain the grafted polypropylene powder.

[0128] Polypropylene grafted powder, C28J6, carbon black VXC500, 3000ppm antioxidant 1010 / 168 (mass ratio 1:1), 0.15% copper inhibitor 1024, and 0.3% release agent 6252 were weighed according to a mass ratio of 30:40:30 (the amounts of antioxidant, copper inhibitor, and release agent are based on the total mass of polypropylene grafted powder, C28J6, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material C6. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0129] Example 7

[0130] The polypropylene grafted powder, C28J6, carbon black VXC500, and 4000ppm antioxidant 1035, 0.15% copper inhibitor 1024, and 0.3% processing aid 5920 were weighed according to a mass ratio of 22:50:28 (the amounts of antioxidant, copper inhibitor, and processing aid are based on the total mass of the polypropylene grafted powder, C28J6, and carbon black VXC500). The mixture was granulated in a twin-screw extruder at a zone temperature of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 250rpm to obtain the semi-conductive shielding material C7. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0131] Comparative Example 1

[0132] PP1, C28J6, carbon black VXC500, 3000ppm antioxidant 1010 / 168 (mass ratio 1:1), 0.15% copper inhibitor 1024, and 0.3% stripping agent 6252 were weighed according to a mass ratio of 30:40:30 (the amounts of antioxidant, copper inhibitor, and stripping agent are based on the total mass of PP1, C28J6, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material D1. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0133] Comparative Example 2

[0134] 2.0 kg of PPH-F03D powder (after sieving to remove fine powder smaller than 40 mesh) was weighed and added to a 10 L reactor equipped with a mechanical stirrer. The reaction system was sealed, and nitrogen was used for purging to remove oxygen. 1.0 g of benzoyl peroxide and 59.8 g of vinyl acetate were added, and the mixture was stirred and mixed for 30 minutes. The mixture was then swollen at 45 °C for 1 hour, and the temperature was raised to 95 °C for 3 hours. After the reaction was completed, the mixture was cooled and dried under vacuum at 70 °C for 10 hours to obtain the polypropylene grafted powder.

[0135] Polypropylene grafted powder, C28J6, carbon black VXC500, 4000ppm antioxidant 1035, 0.15% copper inhibitor 1024, and 0.3% processing aid 5920 were weighed according to a mass ratio of 22:50:28 (the amounts of antioxidant, copper inhibitor, and processing aid are based on the total mass of polypropylene grafted powder, C28J6, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material D2. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0136] Comparative Example 3

[0137] Weigh 2.0 kg of PP1 powder (after sieving to remove fine powder smaller than 40 mesh) and add it to a 10 L reactor equipped with a mechanical stirrer. Seal the reaction system and purge with nitrogen to remove oxygen. Add 5.8 g of tert-butyl peroxide (2-ethylhexanoate) and 389.5 g of acrylic acid, stir and mix for 30 minutes, add 2 kg of water as a dispersant, and allow to swell at 60 °C for 2 hours. Then raise the temperature to 90 °C and react for 4 hours. After the reaction is complete, cool the mixture, filter to remove the water dispersant, and vacuum dry at 70 °C for 10 hours to obtain the grafted polypropylene powder.

[0138] Polypropylene grafted powder, carbon black VXC500, 3000ppm antioxidant 1010 / 168 (mass ratio 1:1), 0.15% copper inhibitor 1024, and 0.3% release agent 6252 were weighed according to a mass ratio of 70:30 (the amounts of antioxidant, copper inhibitor, and release agent are based on the total mass of polypropylene grafted powder, C28J6, and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material D4. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0139] Comparative Example 4

[0140] C28J6, carbon black VXC500, 3000ppm antioxidant 1010 / 168 (mass ratio 1:1:1), 0.15% copper inhibitor 1024, and 0.3% stripper 6252 were weighed according to a mass ratio of 70:30 (the amounts of antioxidant, copper inhibitor, and stripper are based on the total mass of C28J6 and carbon black VXC500). Granulation was performed using a reciprocating single-screw compounding extruder at zone temperatures of 190-200-210-220-220-220-220-210-200℃ and a screw speed of 300rpm to obtain semi-conductive shielding material D4. The performance parameters of the obtained product were tested, and the results are shown in Table 2.

[0141] Table 2

[0142]

[0143]

[0144] Comparing the data of Example 1 and Comparative Example 1, it can be seen that the semiconductive shielding material without the introduction of functional monomers does not meet the requirements for insulation and shielding peel force.

[0145] Comparing the data of Example 2 and Comparative Example 2, it can be seen that the semiconductive shielding material with a low amount of functional monomers has poor electrical performance and high peel strength between insulation and shielding.

[0146] Comparing the data of Example 1 and Comparative Example 3, it can be seen that when the semiconductive shielding material is mainly composed of propylene polymer modified with functional monomers, the mechanical properties of the shielding material do not meet the requirements for use.

[0147] Comparing the data of Example 1 and Comparative Example 4, it can be seen that when the semiconductive shielding material is mainly composed of ethylene copolymer, the shielding material separates from the polypropylene insulating material and is not suitable for the use of polypropylene-based insulating materials.

[0148] In summary, as can be seen from the data in Table 2, the semiconductive shielding material obtained by this invention not only has excellent electrical properties, good mechanical properties, and peelability.

[0149] The various embodiments of the present invention have been described above. These descriptions are exemplary and not exhaustive, nor are they limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. An environmentally friendly peelable semiconductive shielding material, characterized in that, This semiconductive shielding material contains functional monomer-grafted modified propylene polymer, ethylene copolymer, conductive filler, and antioxidant; Based on the total weight of the functional monomer grafted modified propylene polymer, ethylene copolymer, and conductive filler, the content of the functional monomer grafted modified propylene polymer is 5-60 wt%, the content of the ethylene copolymer is 15-75 wt%, and the content of the conductive filler is 15-45 wt%; based on the weight of the functional monomer grafted modified propylene polymer, the content of the functional monomer structural units in the grafted state in the functional monomer grafted modified propylene polymer is 5-30 wt%.

2. The environmentally friendly peelable semiconductive shielding material according to claim 1, wherein, Based on the total weight of the functional monomer-grafted propylene polymer, ethylene copolymer, and conductive filler, the content of the functional monomer-grafted propylene polymer is 8-55 wt%, preferably 10-45 wt%, the content of the ethylene copolymer is 25-65 wt%, preferably 28-58 wt%, and the content of the conductive filler is 18-35 wt%. Based on the weight of the functional monomer-grafted propylene polymer, the content of the functional monomer structural units in the grafted state in the functional monomer-grafted propylene polymer is 10-25 wt%. Preferably, the semiconductive shielding material has at least one of the following characteristics: a melt flow rate of 0.01-8 g / 10 min at 230°C and a load of 2.16 kg, more preferably 0.01-4 g / 10 min; a melting temperature Tm of 110-180°C, more preferably 120-170°C; and a density of 0.900-1.100 g / cm³. 3 .

3. The environmentally friendly peelable semiconductive shielding material according to claim 1, wherein, The semiconductive shielding material has a volume resistivity of no more than 40 Ω·cm at 20°C, preferably no more than 30 Ω·cm; and a volume resistivity of no more than 200 Ω·cm at 105°C, preferably no more than 120 Ω·cm. The peel force between the semiconductive shielding material and the insulating layer is no more than 40 N / cm, preferably no more than 20 N / cm. The tensile strength of the semiconductive shielding material is 5-30 MPa, preferably 10-25 MPa; and the elongation at break is 50-800%, preferably 100-600%.

4. The environmentally friendly peelable semiconductive shielding material according to claim 1, wherein, The functional monomer is selected from at least one monomer having the structure shown in formula (1). In equation (1), R b R c R d Each is independently selected from H, substituted or unsubstituted alkyl groups; R a Selected from substituted or unsubstituted alkyl, substituted or unsubstituted alkoxy, substituted or unsubstituted aryl, substituted or unsubstituted ester, substituted or unsubstituted carboxyl, substituted or unsubstituted cycloalkyl or heterocyclic, cyano, substituted or unsubstituted silyl; Preferably, R b R c R d Each is independently selected from H, substituted or unsubstituted C1-C6 alkyl groups; R a Selected from substituted or unsubstituted C1-C 20 Alkyl, substituted or unsubstituted C1-C 20 Alkoxy, substituted or unsubstituted C6-C 20 aryl, substituted or unsubstituted C1-C 20 Ester group, substituted or unsubstituted C1-C 20 Carboxyl, substituted or unsubstituted C3-C 20 Cycloalkyl or heterocyclic, cyano, substituted or unsubstituted C3-C 20 Silyl group; the substituted group is halogen, hydroxyl, amino, C1-C 12 Alkyl, C3-C6 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 Acyloxy group; More preferably, R b R c R d Each is independently selected from H, substituted or unsubstituted C1-C6 alkyl groups; R a Selected from the group shown in formula (2), the group shown in formula (3), the group shown in formula (4), the group shown in formula (5), the group shown in formula (6), a combination of the group shown in formula (6) and the group shown in formula (7), and heterocyclic groups; In equation (2), R 4 -R 8 Each is independently selected from H, halogen, hydroxyl, amino, phosphate group, sulfonic acid group, substituted or unsubstituted C1-C. 12 Alkyl, substituted or unsubstituted C3-C 12 cycloalkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C1-C 12 ester group, substituted or unsubstituted C1-C 12 The substituted amino group, wherein the substituted group is selected from halogen, hydroxyl, amino, phosphate, sulfonic acid, C1-C 12 Alkyl, C3-C 12 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 ester group, C1-C 12 The amino group; preferably, R 4 -R 8 Each is independently selected from H, halogen, hydroxyl, amino, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C6 alkoxy; In equation (3), R4-R 10 Each is independently selected from H, halogen, hydroxyl, amino, phosphate group, sulfonic acid group, substituted or unsubstituted C1-C. 12 Alkyl, substituted or unsubstituted C3-C 12 cycloalkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C1-C 12 ester group, substituted or unsubstituted C1-C 12 The substituted amino group, wherein the substituted group is selected from halogen, hydroxyl, amino, phosphate, sulfonic acid, C1-C 12 Alkyl, C3-C 12 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 ester group, C1-C 12 The amino group; preferably, R4-R 10 Each of the groups is independently selected from H, halogen, hydroxyl, amino, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C6 alkoxy, wherein the substituted group is selected from halogen, hydroxyl, amino, C1-C6 alkyl, C1-C6 alkoxy; In equation (4), R4'-R 10 Each group is independently selected from H, halogen, hydroxyl, amino, phosphate, sulfonic acid, substituted or unsubstituted C1-C. 12 Alkyl, substituted or unsubstituted C3-C 12 cycloalkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C1-C 12 ester group, substituted or unsubstituted C1-C 12 The substituted amino group, wherein the substituted group is selected from halogen, hydroxyl, amino, phosphate, sulfonic acid, C1-C 12 Alkyl, C3-C 12 cycloalkyl, C1-C 12 alkoxy groups, C1-C 12 ester group, C1-C 12 The amino group; preferably, R4'-R 10 Each of the following is independently selected from H, halogen, hydroxyl, amino, substituted or unsubstituted C1-C6 alkyl, substituted or unsubstituted C1-C6 alkoxy, wherein the substituted group is selected from halogen, hydroxyl, amino, C1-C6 alkyl, C1-C6 alkoxy; In equation (5), R', R”, and R”' are each independently selected from substituted or unsubstituted C1-C. 12 Straight-chain alkyl, substituted or unsubstituted C3-C 12 Branched alkyl, substituted or unsubstituted C1-C 12 alkoxy, substituted or unsubstituted C1-C 12 The acyloxy group; preferably, R', R"', R"' are each independently selected from substituted or unsubstituted C1-C6 straight-chain alkyl, substituted or unsubstituted C3-C6 branched alkyl, substituted or unsubstituted C1-C6 alkoxy, substituted or unsubstituted C1-C6 acyloxy. In equation (6), R m Selected from the following groups, substituted or unsubstituted: C1-C 20 Straight-chain alkyl, C3-C 20 Branched alkyl, C3-C 12 cycloalkyl, C3-C 12 Epoxyalkyl, C3-C 12 Epoxyalkylalkyl, wherein the substituted group is selected from at least one of halogen, amino and hydroxyl groups; The heterocyclic group is selected from imidazole, pyrazol, carbazole, pyrrolidone, pyridinyl, piperidinyl, caprolactam, pyrazinyl, thiazolyl, purine, morpholino, and oxazolino.

5. The environmentally friendly peelable semiconductive shielding material according to claim 4, wherein, The functional monomers are acrylate monomers and optionally acrylate monomers; Preferably, the acrylate monomer is selected from at least one of methyl methacrylate, sec-butyl methacrylate, ethyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, tert-butyl methacrylate, isooctyl methacrylate, dodecyl methacrylate, coconut oleate methacrylate, octadecyl methacrylate, dimethylaminoethyl methacrylate, diethylaminoethyl methacrylate, dimethylaminopropyl methacrylate, and glycidyl methacrylate; preferably, the acrylic monomer is selected from at least one of acrylic acid, methacrylic acid, and 2-ethylacrylic acid; more preferably, the molar ratio of the structural unit derived from the acrylate monomer to the structural unit derived from the acrylic monomer is 1:0-2, more preferably 1:0.125-1.

6. The environmentally friendly peelable semiconductive shielding material according to claim 1, wherein, The propylene polymer is a homopolymer or copolymer polypropylene, having at least one of the following characteristics: a comonomer content of 0-15 mol%, preferably 0-12 mol%, more preferably 0-8 mol%; a melt flow rate of 0.01-10 g / 10 min at 230°C and a load of 2.16 kg, preferably 0.1-5 g / 10 min; a melt temperature Tm of 110-180°C, more preferably 120-170°C; and a weight-average molecular weight of 20 × 10⁻⁶. 4 -50×10 4 g / mol; tensile strength greater than 5 MPa, preferably 10-40 MPa; Preferably, the comonomer of the copolymerized polypropylene is selected from at least one of C2-C8 α-olefins other than propylene; more preferably, the comonomer of the copolymerized polypropylene is selected from at least one of ethylene, 1-butene, 1-pentene, 4-methyl-1-pentene, 1-hexene, 1-heptene and 1-octene; even more preferably, the comonomer of the copolymerized polypropylene is ethylene and / or 1-butene.

7. The environmentally friendly peelable semiconductive shielding material according to claim 1, wherein, The copolymer unit of the ethylene copolymer is selected from polar copolymer units, preferably acrylic acid, methacrylic acid, acrylate, methacrylate, vinyl ester, and more preferably acrylic acid or vinyl ester. Preferably, the ethylene copolymer has at least one of the following characteristics: a polar comonomer content of 0-40 mol%, preferably 10-35 mol%; a melt flow rate of 0.05-25 g / 10 min at 190°C and 2.16 kg load, preferably 1-10 g / 10 min; a melt temperature greater than 40°C, preferably 50°C-140°C; a tensile strength greater than 10 MPa; and an elongation at break greater than 500%.

8. The environmentally friendly peelable semiconductive shielding material according to claim 1, wherein, The conductive filler is selected from one or more of conductive carbon black, carbon nanotubes, graphene, and MXene, preferably conductive carbon black, and more preferably acetylene black; More preferably, the acetylene black has an oil absorption value of not less than 120cc / 100g, an iodine absorption value of not less than 70mg / g, and a residue of not more than 25ppm on a 325-mesh sieve.

9. A method for preparing the environmentally friendly peelable semiconductive shielding material according to any one of claims 1-8, characterized in that, The preparation method includes the following steps: S1: In the presence of an inert gas, a reaction mixture including a propylene polymer and a functional monomer is subjected to a grafting reaction to obtain a propylene polymer grafted with a functional monomer. S2: Mix the materials containing the functional monomer-grafted modified propylene polymer, ethylene copolymer, conductive filler and antioxidant, melt extrude and granulate to obtain the semi-conductive shielding material.

10. The method for preparing the environmentally friendly peelable semiconductive shielding material according to claim 9, wherein, The reaction mixture contains a free radical initiator selected from peroxide free radical initiators and / or azo free radical initiators; the mass ratio of the free radical initiator to the functional monomer is 0.01-10:100, preferably 0.5-5:100; The peroxide-based free radical initiator is preferably selected from at least one of benzoyl peroxide, dicumyl peroxide, di-tert-butyl peroxide, lauroyl peroxide, dodecyl peroxide, tert-butyl peroxide, diisopropyl peroxide, tert-butyl peroxide, and dicyclohexyl peroxide.

11. The method for preparing the environmentally friendly peelable semiconductive shielding material according to claim 9, wherein, The grafting reaction is carried out at a temperature of 30-130°C, preferably 60-120°C, for a time of 0.5-10 hours, preferably 1-6 hours. The temperature of melt extrusion is 170-250℃, preferably 180-230℃, and more preferably 190-220℃.

12. The application of the environmentally friendly peelable semiconductive shielding material according to any one of claims 1-8 in the field of cable semiconductive shielding.

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