阅读说明：本技术 一种用于电线的绝缘层材料及其制备方法 (Insulating layer material for electric wire and preparation method thereof ) 是由 张世泉 于 2020-10-14 设计创作，主要内容包括：本发明公开了一种用于电线的绝缘层材料,所述绝缘层材料包裹于导体外部,所述绝缘层包括如下重量份的原料：80份聚烯烃,35-40份聚磷酸铵,20-30份超细季戊四醇,10-13份乙烯-醋酸乙烯共聚物,12-18份第一阻燃剂,5-10份第二阻燃剂,2-3份抗氧化剂,3-5份加工助剂,方法包括(1)改性季戊四醇；(2)混料成型；(3)辐照交联；(4)挤出切粒过筛。本发明的优点在于通过将季戊四醇阻燃体系以及聚烯烃/膨胀性阻燃体系通过辐照交联,从而极大提升整体材料的阻燃性能以及防火性能,提升整体在水汽以及杂质影响下的绝缘性能,使用寿命更加长,从而与城市建筑设计寿命同步。(The invention discloses an insulating layer material for an electric wire, which is wrapped outside a conductor and comprises the following raw materials in parts by weight: 80 parts of polyolefin, 35-40 parts of ammonium polyphosphate, 20-30 parts of superfine pentaerythritol, 10-13 parts of ethylene-vinyl acetate copolymer, 12-18 parts of first flame retardant, 5-10 parts of second flame retardant, 2-3 parts of antioxidant and 3-5 parts of processing aid, and the method comprises (1) modified pentaerythritol; (2) mixing and forming; (3) performing irradiation crosslinking; (4) extruding, granulating and sieving. The invention has the advantages that the flame retardant performance and the fireproof performance of the whole material are greatly improved by crosslinking the pentaerythritol flame retardant system and the polyolefin/expansible flame retardant system through irradiation, the insulating performance of the whole material under the influence of water vapor and impurities is improved, the service life is prolonged, and the service life is synchronous with the design life of urban buildings.)

1. The insulating layer material for the electric wire is wrapped outside a conductor and is characterized by comprising the following raw materials in parts by weight: 80 parts of polyolefin, 35-40 parts of ammonium polyphosphate, 20-30 parts of superfine pentaerythritol, 10-13 parts of ethylene-vinyl acetate copolymer, 12-18 parts of first flame retardant, 5-10 parts of second flame retardant, 2-3 parts of antioxidant and 3-5 parts of processing aid.

2. An insulating layer material for electric wire according to claim 1, characterized in that: the polyolefin comprises maleic anhydride grafted metallocene polyethylene accounting for 30-40% of the whole mass of the polyolefin, ethylene-octene copolymer accounting for 30-40% of the whole mass of the polyolefin, and the balance of metallocene polyethylene.

3. An insulating layer material for electric wire according to claim 1, characterized in that: the first flame retardant is selected from one of melamine urate, melamine triallyl cyanurate and ammonium borate.

4. An insulating layer material for electric wire according to claim 1, characterized in that: the ammonium polyphosphate is high-polymerization-degree ammonium polyphosphate, and the polymerization degree of the ammonium polyphosphate is more than 1500.

5. An insulating layer material for electric wire according to claim 1, characterized in that: the antioxidant is selected from one of antioxidant 300, antioxidant 1010 or 2, 6-di-tert-butyl-p-cresol.

6. An insulating layer material for electric wire according to claim 1, characterized in that: the processing aid is one or more of kaolin, calcium carbonate and organic montmorillonite.

7. An insulating layer material for electric wire according to claim 1, characterized in that: the second flame retardant is selected from one or more of aluminum diethylphosphinate, zinc borate, aluminum hydroxide and magnesium hydroxide.

8. A preparation method of an insulating layer material for electric wires is characterized by comprising the following steps: the method comprises the following steps:

(1) firstly weighing ammonium polyphosphate and ethylene-vinyl acetate copolymer according to the weight parts, carrying out melt blending in a rheometer to prepare master batch, uniformly mixing the master batch and superfine pentaerythritol, and mixing the mixture in the rheometer at the temperature of 120-;

(2) weighing the rest components in parts by weight, mixing the polyolefin and the second flame retardant in a rheometer at the temperature of 130-150 ℃ and the rotation speed of 250-300 r/min for 15-20 min, mixing the modified pentaerythritol prepared in the step (1) and the rest components in the rheometer according to the same conditions, and forming by a flat vulcanizing machine after the mixing is finished;

(3) performing radiation crosslinking on the mixture formed in the step (2), wherein the radiation source is gamma⁶⁰Co, source strength 3.5x10¹⁵~3.7x10¹⁵Bq, at room temperature, N₂Irradiating the mixed material at the irradiation dose of 10-12kGy/h in the atmosphere for 3-8 h;

(4) and (4) feeding the mixed material subjected to radiation crosslinking in the step (3) into a single-screw extruder for extruding and granulating, wherein the extrusion temperature is 110-150 ℃, the extrusion speed is 200-300 r/min, and sieving to obtain the final insulating layer material.

Technical Field

The invention relates to the technical field of preparation of an insulating outer layer of a wire, in particular to an insulating layer material for the wire and a preparation method thereof.

Background

According to incomplete statistics, more than 85% of electric fires in domestic and foreign building fields are caused by short circuit and ignition of lines due to aging of wires and cables. The aging of the sheath and insulation of the concealed wiring used in a large number of old buildings has occurred, and replacement is urgently required. With the acceleration of urban intellectualization and high-rise building development pace, the synchronization of the design life of building materials and buildings is the direction of future development. The hidden electric wire is an important component of building materials, and in order to prevent the damage to a building structure caused by midway line changing, the hidden electric wire should have the same service life as 70-year house property rights as much as possible. Meanwhile, with the continuous improvement of the matching system in China, the hidden wiring is kept at a green pace. The outer layer of the existing hidden-coated wire has low insulating property, and the insulating property and the service life of the wire are influenced under the influence of water vapor or conductive impurities.

Disclosure of Invention

The invention aims to provide an insulating layer material for an electric wire and a preparation method thereof.

The technical purpose of the invention is realized by the following technical scheme:

the insulating layer material for the electric wire is wrapped outside a conductor and is characterized by comprising the following raw materials in parts by weight: 80 parts of polyolefin, 35-40 parts of ammonium polyphosphate, 20-30 parts of superfine pentaerythritol, 10-13 parts of ethylene-vinyl acetate copolymer, 12-18 parts of first flame retardant, 5-10 parts of second flame retardant, 2-3 parts of antioxidant and 3-5 parts of processing aid.

Preferably, the polyolefin comprises maleic anhydride grafted metallocene polyethylene accounting for 30-40% of the overall mass of the polyolefin, ethylene-octene copolymer accounting for 30-40% of the overall mass of the polyolefin, and the balance of metallocene polyethylene.

Preferably, the first flame retardant is selected from one of melamine urate, melamine triallyl cyanurate and ammonium borate.

Preferably, the ammonium polyphosphate is ammonium polyphosphate with high polymerization degree, and the polymerization degree of the ammonium polyphosphate is more than 1500.

Preferably, the antioxidant is selected from one of antioxidant 300, antioxidant 1010 or 2, 6-di-tert-butyl-p-cresol.

Preferably, the processing aid is selected from one or more of kaolin, calcium carbonate and organic montmorillonite.

Preferably, the second flame retardant is selected from one or more of aluminum diethylphosphinate, zinc borate, aluminum hydroxide and magnesium hydroxide.

A preparation method of an insulating layer material for electric wires is characterized by comprising the following steps: the method comprises the following steps:

(1) firstly weighing ammonium polyphosphate and ethylene-vinyl acetate copolymer according to the weight parts, carrying out melt blending in a rheometer to prepare master batch, uniformly mixing the master batch and superfine pentaerythritol, and mixing the mixture in the rheometer at the temperature of 120-;

(2) weighing the rest components in parts by weight, mixing the polyolefin and the second flame retardant in a rheometer at the temperature of 130-150 ℃ and the rotation speed of 250-300 r/min for 15-20 min, mixing the modified pentaerythritol prepared in the step (1) and the rest components in the rheometer according to the same conditions, and forming by a flat vulcanizing machine after the mixing is finished;

(3) performing radiation crosslinking on the mixture formed in the step (2), wherein the radiation source is gamma⁶⁰Co，The source intensity was 3.5x10¹⁵~3.7x10¹⁵Bq, at room temperature, N₂Irradiating the mixed material at the irradiation dose of 10-12kGy/h in the atmosphere, wherein the irradiation time is 3-8;

(4) and (4) feeding the mixed material subjected to radiation crosslinking in the step (3) into a single-screw extruder for extruding and granulating, wherein the extrusion temperature is 110-150 ℃, the extrusion speed is 200-300 r/min, and sieving to obtain the final insulating layer material.

In conclusion, the invention has the following beneficial effects: according to the invention, the pentaerythritol flame-retardant system and the polyolefin/intumescent flame-retardant system are crosslinked by irradiation, so that the flame-retardant property and the fireproof property of the whole material are greatly improved, the insulating property of the whole material under the influence of water vapor and impurities is improved, the service life is prolonged, and the service life is synchronous with the design life of urban buildings.

Detailed Description

The following further describes the embodiments of the present invention, which are not to be construed as limiting the invention.

Example 1

The insulating layer material for the electric wire is wrapped outside a conductor and comprises the following raw materials in parts by weight: 30 parts of maleic anhydride grafted metallocene polyethylene, 25 parts of ethylene-octene copolymer, 25 parts of metallocene polyethylene, 35 parts of high-polymerization-degree ammonium polyphosphate, 20 parts of superfine pentaerythritol, 11 parts of ethylene-vinyl acetate copolymer, 15 parts of melamine triallyl cyanurate, 2 parts of aluminum diethylphosphinate, 2 parts of aluminum hydroxide, 2 parts of antioxidant 300, 2 parts of kaolin, 2 parts of calcium carbonate and the polymerization degree of ammonium polyphosphate is more than 1500.

(1) Firstly, high-polymerization ammonium polyphosphate and ethylene-vinyl acetate copolymer are subjected to melt blending in a rheometer to prepare master batch, and then the master batch and superfine pentaerythritol are mixed uniformly and mixed in the rheometer for 15 minutes at 120 ℃ at 250 rpm to prepare the modified pentaerythritol.

(2) Weighing the rest components in parts by weight, mixing polyolefin, aluminum diethylphosphinate and aluminum hydroxide in a rheometer at 130 ℃ at 300 rpm for 15-20 minutes, mixing the modified pentaerythritol prepared in the step (1) with the rest components in the rheometer under the same condition, and molding by a flat-plate vulcanizing machine after the mixing is finished.

(3) Performing radiation crosslinking on the mixture formed in the step (2), wherein the radiation source is gamma⁶⁰Co, source strength 3.5x10¹⁵Bq, at room temperature, N₂Irradiating the mixed material at the irradiation dose of 10kGy/h in the atmosphere for 3 h;

(4) and (4) feeding the mixed material subjected to radiation crosslinking in the step (3) into a single-screw extruder for extruding and pelletizing, wherein the extrusion temperature is 120 ℃, the extrusion speed is 230 r/min, and sieving to obtain the final insulating layer material.

Example 2

The insulating layer material for the electric wire is wrapped outside a conductor and comprises the following raw materials in parts by weight: 25 parts of maleic anhydride grafted metallocene polyethylene, 28 parts of ethylene-octene copolymer, 27 parts of metallocene polyethylene, 37 parts of high-polymerization-degree ammonium polyphosphate, 25 parts of superfine pentaerythritol, 13 parts of ethylene-vinyl acetate copolymer, 15 parts of ammonium borate, 1 part of zinc borate, 2 parts of magnesium hydroxide, 3 parts of 2, 6-di-tert-butyl-p-cresol, 1 part of kaolin, 3 parts of organic montmorillonite, and the polymerization degree of the ammonium polyphosphate is more than 1500.

(1) Firstly, high-polymerization ammonium polyphosphate and ethylene-vinyl acetate copolymer are melted and blended in a rheometer to prepare master batch, and then the master batch and superfine pentaerythritol are mixed uniformly and mixed in the rheometer for 10 minutes at 130 ℃ at 250 rpm to prepare the modified pentaerythritol.

(2) Weighing the rest components in parts by weight, mixing polyolefin, aluminum diethylphosphinate and magnesium hydroxide in a rheometer at 130 ℃ at 300 r/min for 18 minutes, mixing the modified pentaerythritol prepared in the step (1) with the rest components in the rheometer under the same condition, and forming by a flat-plate vulcanizing machine after the mixing is finished;

(3) performing radiation crosslinking on the mixture formed in the step (2), wherein the radiation source is gamma⁶⁰Co, source strength 3.6x10¹⁵Bq, at room temperature, N₂The mixed material is irradiated under the atmosphere with the irradiation dose of 11kGy/h, and the irradiation time is 5h。

(4) And (4) feeding the mixed material subjected to radiation crosslinking in the step (3) into a single-screw extruder for extruding and pelletizing, wherein the extrusion temperature is 130 ℃, the extrusion speed is 260 r/min, and sieving to obtain the final insulating layer material.

Example 3

The insulating layer material for the electric wire is wrapped outside a conductor and comprises the following raw materials in parts by weight: 28 parts of maleic anhydride grafted metallocene polyethylene, 30 parts of ethylene-octene copolymer, 22 parts of metallocene polyethylene, 40 parts of high-polymerization-degree ammonium polyphosphate, 26 parts of superfine pentaerythritol, 12 parts of ethylene-vinyl acetate copolymer, 18 parts of melamine urate, 7 parts of magnesium hydroxide, 3 parts of antioxidant 1010, 4 parts of organic montmorillonite, wherein the polymerization degree of the ammonium polyphosphate is more than 1500.

(1) Firstly, high-polymerization ammonium polyphosphate and ethylene-vinyl acetate copolymer are subjected to melt blending in a rheometer to prepare master batch, and then the master batch and superfine pentaerythritol are mixed uniformly and mixed in the rheometer for 10 minutes at 140 ℃ at 270 r/min to prepare the modified pentaerythritol.

(2) Weighing the rest components in parts by weight, mixing polyolefin, aluminum diethylphosphinate and magnesium hydroxide in a rheometer at 130 ℃ at 300 r/min for 18 minutes, mixing the modified pentaerythritol prepared in the step (1) with the rest components in the rheometer under the same condition, and forming by a flat-plate vulcanizing machine after the mixing is finished.

(3) Performing radiation crosslinking on the mixture formed in the step (2), wherein the radiation source is gamma⁶⁰Co, source strength 3.5x10¹⁵Bq, at room temperature, N₂And irradiating the mixed material at the irradiation dose of 12kGy/h in the atmosphere for 7 h.

(4) And (4) feeding the mixed material subjected to radiation crosslinking in the step (3) into a single-screw extruder for extruding and pelletizing, wherein the extrusion temperature is 150 ℃, the extrusion speed is 250 revolutions per minute, and sieving to obtain the final insulating layer material.

According to the invention, the pentaerythritol flame-retardant system and the polyolefin/intumescent flame-retardant system are crosslinked by irradiation, so that the flame retardant property of the whole material is greatly improvedAnd fire resistance, and improves the insulation performance of the whole body under the influence of water vapor and impurities, the breakdown field strength of the whole body is more than 27MV/m, and the volume resistivity is more than 2x10¹³Omega m, the other mechanical properties meet the national standard, the service life is longer, and therefore the service life is synchronous with the design life of urban buildings.

While the invention has been described with reference to a preferred embodiment, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the spirit and scope of the invention.