CN111073126A - Heat deformation resistant semiconductive polyethylene shielding material - Google Patents

Heat deformation resistant semiconductive polyethylene shielding material Download PDF

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Publication number
CN111073126A
CN111073126A CN201911309841.XA CN201911309841A CN111073126A CN 111073126 A CN111073126 A CN 111073126A CN 201911309841 A CN201911309841 A CN 201911309841A CN 111073126 A CN111073126 A CN 111073126A
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China
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parts
shielding material
thermal deformation
polyethylene
deformation resistant
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CN201911309841.XA
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Inventor
丁子龙
邹惠忠
张雪良
杨建锋
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Cgn Delta Jiangsu Plastics Co ltd
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Cgn Delta Jiangsu Plastics Co ltd
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Priority to CN201911309841.XA priority Critical patent/CN111073126A/en
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    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L23/00Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers
    • C08L23/02Compositions of homopolymers or copolymers of unsaturated aliphatic hydrocarbons having only one carbon-to-carbon double bond; Compositions of derivatives of such polymers not modified by chemical after-treatment
    • C08L23/04Homopolymers or copolymers of ethene
    • C08L23/08Copolymers of ethene
    • C08L23/0807Copolymers of ethene with unsaturated hydrocarbons only containing more than three carbon atoms
    • C08L23/0815Copolymers of ethene with aliphatic 1-olefins
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00Specific properties of additives
    • C08K2201/001Conductive additives
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08KUse of inorganic or non-macromolecular organic substances as compounding ingredients
    • C08K2201/00Specific properties of additives
    • C08K2201/014Additives containing two or more different additives of the same subgroup in C08K
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2201/00Properties
    • C08L2201/08Stabilised against heat, light or radiation or oxydation
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2203/00Applications
    • C08L2203/20Applications use in electrical or conductive gadgets
    • C08L2203/202Applications use in electrical or conductive gadgets use in electrical wires or wirecoating
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2205/00Polymer mixtures characterised by other features
    • C08L2205/03Polymer mixtures characterised by other features containing three or more polymers in a blend
    • C08L2205/035Polymer mixtures characterised by other features containing three or more polymers in a blend containing four or more polymers in a blend
    • CCHEMISTRY; METALLURGY
    • C08ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08LCOMPOSITIONS OF MACROMOLECULAR COMPOUNDS
    • C08L2207/00Properties characterising the ingredient of the composition
    • C08L2207/06Properties of polyethylene
    • C08L2207/062HDPE

Abstract

The invention relates to a thermal deformation resistant semiconductive polyethylene shielding material which comprises the following components in parts by mass: 704290-105 parts of linear low-density polyethylene, 609815-20 parts of high-density polyethylene, 10-15 parts of polyolefin, 15-20 parts of ethylene-vinyl acetate copolymer, 2-5 parts of p-hydroxybenzene sulfonic acid, 10-20 parts of 5-sulfosalicylic acid, 40-50 parts of conductive carbon black, 5-10 parts of 3, 6-dibromo-1, 2-phenylenediamine, 5-10 parts of graphite, 1-3 parts of lubricant, 1-2 parts of organic silicon master batch GT-3001, 1-2 parts of polyethylene wax, 10100.5-1 part of antioxidant and 1-3 parts of white oil. The thermal deformation resistant semiconductive polyethylene shielding material has thermal deformation resistance and low temperature embrittlement resistance, the volume resistance change rate between 20 ℃ and 90 ℃ is shortened, the processing technology performance of the polyethylene shielding material is excellent, the extrusion surface is smoother, and the phenomenon of cable extrusion and scorching is avoided.

Description

Heat deformation resistant semiconductive polyethylene shielding material
Technical Field
The invention belongs to the technical field of cable shielding materials, and particularly relates to a thermal deformation resistant semiconductive polyethylene shielding material.
Background
The semi-conductive shielding material is an important component of a medium-high voltage cable, so that the electric field inside the cable can be distributed more uniformly, the damage of stress concentration to a cable insulating layer is reduced, and the safety and the service life of the cable are greatly influenced. In the past, various domestic research institutions and enterprises are dedicated to improving the quality level of the semiconductive shielding material in China and reducing the gap with advanced manufacturers in the world. The preparation process of the semiconductive shielding material is continuously improved, and the formula is continuously optimized. But the quality level of the domestic semiconductive shielding material is still not small different from the international advanced level because of the problems in various aspects such as raw materials, industrial foundation, research and development fund and the like. The rapid development of the cable market today places higher demands on the quality and performance of the semiconducting shield. Therefore, it is an effort for those skilled in the art to overcome the above technical problems.
The cross-linked polyethylene insulated inner and outer shielding material of the medium and high voltage power cable generally adopts a semi-conductive shielding material, and the composition of the semi-conductive shielding material is prepared from ethylene-vinyl acetate copolymer, linear low-density polyethylene, carbon black and the like. However, linear low-density polyethylene is used as a base material, the semiconductive shielding material has poor thermal stability and poor heat deformation resistance, and meanwhile, the linear low-density polyethylene has relatively strong electrical insulation, a large amount of conductive carbon black is required to be added in the process of manufacturing the shielding to improve the electrical conductivity of the material, but the addition of the large amount of conductive carbon black greatly reduces the physical and chemical properties and the processing property of the shielding material, the surface smoothness of the shielding layer after thin-wall extrusion is extremely poor, and uneven pits or cracks and fractures exist in the semiconductive shielding material if the semiconductive shielding material cannot ensure the smooth surface, so that partial discharge or insulation breakdown is caused.
Disclosure of Invention
The invention aims to provide a thermal deformation resistant semiconductive polyethylene shielding material which has thermal deformation resistance and low-temperature embrittlement resistance, shortens the volume resistance change rate between 20 ℃ and 90 ℃, has excellent processing performance, has a smoother extrusion surface and does not have the phenomenon of cable extrusion and scorching.
In order to achieve the purpose of the invention, the technical scheme adopted by the invention is as follows: the thermal deformation resistant semiconductive polyethylene shielding material comprises the following components in parts by mass:
704290-105 parts of linear low-density polyethylene,
609815-20 parts of high-density polyethylene,
10-15 parts of polyolefin,
15-20 parts of ethylene-vinyl acetate copolymer,
2-5 parts of p-hydroxybenzene sulfonic acid,
10-20 parts of 5-sulfosalicylic acid,
40-50 parts of conductive carbon black,
5-10 parts of 3, 6-dibromo-1, 2-phenylenediamine,
5-10 parts of graphite,
1-3 parts of a lubricant,
1-2 parts of organic silicon master batch GT-3001,
1-2 parts of polyethylene wax,
10100.5-1 part of an antioxidant,
26# 1-3 parts of white oil.
The technical scheme of the further improvement of the technical scheme is as follows:
1. in the above embodiment, the lubricant is at least one selected from stearic acid, zinc stearate, and calcium stearate.
2. In the above scheme, the polyolefin is any one of DF810 and DF805 produced by mitsui chemical of japan.
3. In the scheme, the ethylene-vinyl acetate copolymer is any one of V4610J and V5110J produced by Yangzubusf.
4. In the scheme, the conductive carbon black is any one of VXC72R and VXC72 which are made by Karper products in the United states.
Due to the application of the technical scheme, compared with the prior art, the invention has the following advantages:
1. the thermal deformation resistant semiconductive polyethylene shielding material adopts linear low density polyethylene 7042, high density polyethylene 6098, polyolefin and ethylene-vinyl acetate copolymer to form a shielding material base material, and 5-sulfosalicylic acid and p-hydroxybenzene sulfonic acid are added into the base material, so that the thermal deformation resistance of the product is improved, the thermal deformation temperature is improved from 100 ℃ to 120 ℃, the deformation rate is about 5%, and the thermal deformation resistant semiconductive polyethylene shielding material has good low temperature embrittlement resistance.
2. According to the heat-deformation-resistant semiconductive polyethylene shielding material, 3, 6-dibromo-1, 2-phenylenediamine is further added on the basis of a shielding material base material and 5-sulfosalicylic acid, so that the filling property of the base material to conductive carbon black is improved, the conductive carbon black is fully mixed and dispersed, the volume resistance change rate between 20 ℃ and 90 ℃ is reduced, the excellent processing technological property of the material is ensured, the extrusion surface of the polyethylene shielding material is smoother, and the phenomenon of cable extrusion and scorching is avoided.
Detailed Description
The invention is further described below with reference to the following examples:
examples 1 to 4: the thermal deformation resistant semiconductive polyethylene shielding material comprises the following components in parts by mass as shown in Table 1:
TABLE 1
Figure 310421DEST_PATH_IMAGE002
The lubricant of example 1 is zinc stearate, the lubricant of example 2 is calcium stearate, the lubricant of example 3 is a mixture of zinc stearate and stearic acid, and the lubricant of example 4 is a mixture of calcium stearate and stearic acid;
the polyolefin of example 1 and example 2 was DF810 produced by mitsui chemicals, and the polyolefin of example 3 and example 4 was DF805 produced by mitsui chemicals;
the ethylene-vinyl acetate copolymers of examples 1 and 3 are V4610J from yankee basf, and the ethylene-vinyl acetate copolymers of examples 2 and 4 are V5110J from yankee basf;
the conductive carbon black of examples 1 and 2 is VXC72R, a product of american karposi, and the conductive carbon black of examples 3 and 4 is VXC72, a product of american karposi.
The thermal deformation resistant semiconductive polyethylene shielding material is prepared by the following steps:
firstly, 704290-105 parts of linear low-density polyethylene, 609815-20 parts of high-density polyethylene, 10-15 parts of polyolefin, 15-20 parts of ethylene-vinyl acetate copolymer, 40-50 parts of conductive carbon black, 2-5 parts of p-hydroxybenzene sulfonic acid, 10-20 parts of 5-sulfosalicylic acid and 5-10 parts of 3, 6-dibromo-1, 2-phenylenediamine are put into an internal mixer to be internally mixed for 2-3 minutes according to corresponding parts by weight;
opening an internal mixing bin, then putting 5-10 parts of graphite, 1-3 parts of lubricant, 1-2 parts of organic silicon master batch GT-3001-2 parts, 1-2 parts of polyethylene wax, 0.5-1 part of antioxidant 1010 and 1-3 parts of white oil into an internal mixer according to corresponding parts by weight of 1-3 parts, carrying out internal mixing for 10-12 minutes, and discharging after the temperature reaches 150 ℃ and the materials are fully and uniformly mixed;
and step three, adding the material discharged in the step (2) into a double-screw extruder for granulation, wherein the double-screw extrusion temperature is 130-160 ℃, the screw rotation speed is 35rpm, cooling, sieving, drying, vacuumizing and packaging.
Comparative examples 1 to 3: the thermal deformation resistant semiconductive polyethylene shielding material comprises the following components in parts by mass as shown in Table 2:
TABLE 2
Figure DEST_PATH_IMAGE004
The lubricant of comparative examples 1-3 was zinc stearate, the polyolefin was DF810, a product of Mitsui Chemicals, Japan, the ethylene-vinyl acetate copolymer was V4610J, a product of Bausff, Yankee, and the conductive carbon black was VXC72R, a product of Karper, USA. The preparation method of a thermal deformation resistant semiconductive polyethylene shield material of comparative examples 1 to 3 is the same as that of examples 1 to 4, and will not be described here.
The thermal deformation resistant semiconductive polyethylene shielding materials obtained in the embodiments 1-4 and the comparative examples 1-3 are subjected to relevant tests according to standards, the tensile strength and the elongation at break are tested according to GB/T1040, the volume resistivity is tested according to GB/T3048, the melt flow rate is tested according to GB/T3682, the low-temperature impact embrittlement temperature (-45 ℃) is tested according to GB/T5470, the 120 ℃ thermal deformation is tested according to GB/T8815, the surface smoothness is visually observed in a phi 45 single-screw extrusion bracing mode, and the mouth mold of an extruder is 1mm thick and 10mm wide. The data obtained are shown in table 3:
TABLE 3
Figure DEST_PATH_IMAGE006
As can be seen from the test data in Table 3, the polyethylene shielding material of comparative example 1 has high volume resistivity at 20 ℃ and high volume resistivity at 90 ℃, has low melt flow rate and poor surface smoothness, and has the cable extrusion scorching condition, but has low temperature impact embrittlement resistance at-45 ℃ and small thermal deformation at 120 ℃. The polyethylene shielding material of comparative example 2 has high volume resistivity at 20 ℃ and volume resistivity at 90 ℃, low melt flow rate, poor surface smoothness, low-temperature impact embrittlement resistance at-45 ℃, large thermal deformation at 120 ℃ and cable extrusion scorching. The polyethylene shielding material of comparative example 3 has low volume resistivity at 20 ℃ and volume resistivity at 90 ℃, high melt flow rate, good surface smoothness, no cable extrusion scorching condition, low temperature impact embrittlement resistance at-45 ℃ and large thermal deformation at 120 ℃.
Therefore, the thermal deformation resistant semiconductive polyethylene shielding material adopts linear low density polyethylene 7042, high density polyethylene 6098, polyolefin and ethylene-vinyl acetate copolymer to form a shielding material base material, and 5-sulfosalicylic acid and p-hydroxybenzene sulfonic acid are added into the base material, so that the thermal deformation resistance of the product is improved, the thermal deformation temperature is improved from 100 ℃ to 120 ℃ and the deformation rate is about 5%, and the thermal deformation resistant semiconductive polyethylene shielding material has good low temperature embrittlement resistance. According to the heat-deformation-resistant semiconductive polyethylene shielding material, 3, 6-dibromo-1, 2-phenylenediamine is further added on the basis of a shielding material base material and 5-sulfosalicylic acid, so that the filling property of the base material to conductive carbon black is improved, the conductive carbon black is fully mixed and dispersed, the volume resistance change rate between 20 ℃ and 90 ℃ is reduced, the excellent processing technological property of the material is ensured, the extrusion surface of the polyethylene shielding material is smoother, and the phenomenon of cable extrusion and scorching is avoided.
The above embodiments are merely illustrative of the technical ideas and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and implement the present invention, and not to limit the protection scope of the present invention. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.

Claims (5)

1. The utility model provides a thermal deformation resistant semiconductive polyethylene shielding material which characterized in that: the composition comprises the following components in parts by weight:
704290-105 parts of linear low-density polyethylene,
609815-20 parts of high-density polyethylene,
10-15 parts of polyolefin,
15-20 parts of ethylene-vinyl acetate copolymer,
2-5 parts of p-hydroxybenzene sulfonic acid,
10-20 parts of 5-sulfosalicylic acid,
40-50 parts of conductive carbon black,
5-10 parts of 3, 6-dibromo-1, 2-phenylenediamine,
5-10 parts of graphite,
1-3 parts of a lubricant,
1-2 parts of organic silicon master batch GT-3001,
1-2 parts of polyethylene wax,
10100.5-1 part of an antioxidant,
26# 1-3 parts of white oil.
2. The thermal deformation resistant semiconductive polyethylene shielding material according to claim 1, wherein: the lubricant is at least one selected from stearic acid, zinc stearate and calcium stearate.
3. The thermal deformation resistant semiconductive polyethylene shielding material according to claim 1, wherein: the polyolefin is any one of DF810 and DF805 produced by Mitsui chemical in Japan.
4. The thermal deformation resistant semiconductive polyethylene shielding material according to claim 1, wherein: the ethylene-vinyl acetate copolymer is any one of V4610J and V5110J produced by Yangzubusf.
5. The thermal deformation resistant semiconductive polyethylene shielding material according to claim 1, wherein: the conductive carbon black is any one of VXC72R and VXC72 which are special products of Kaposi in the United states.
CN201911309841.XA 2019-12-18 2019-12-18 Heat deformation resistant semiconductive polyethylene shielding material Pending CN111073126A (en)

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CN107129625A (en) * 2017-05-09 2017-09-05 上海贝恩科电缆有限公司 A kind of elevator cable semi-conductive screen CABLE MATERIALS and preparation method thereof
CN109593256A (en) * 2018-11-02 2019-04-09 湖北科普达光电材料有限公司 A kind of uvioresistant semiconductive polyethylene sheath material and its application

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Application publication date: 20200428