CN107353473B - Small molecular compound filled high-pressure crosslinked polyethylene cable material and preparation method thereof - Google Patents

Abstract

The invention provides a small molecular compound filled high-pressure crosslinked polyethylene cable material, which is prepared from the following raw materials in parts by weight: 100 parts of polyethylene resin; 0.5-20 parts of a crosslinking agent; 0.5-10 parts of an antioxidant; 0.1-30 parts of a small molecular compound. The invention has the beneficial effects that the high-voltage crosslinked polyethylene cable material has excellent mechanical properties, and the electric properties such as breakdown strength, high pressure resistance and the like of the high-voltage crosslinked polyethylene cable material can be further improved by selecting a proper small molecular compound, so that the application range of the crosslinkable polyethylene cable material can be effectively expanded.

Description

A kind of small molecular compound filling high-pressure cross-linked polyethylene cable material and preparation method thereof

technical field

The invention belongs to the technical field of cable materials, in particular to a high-voltage cross-linked polyethylene cable material and a preparation method thereof.

Background technique

As a supporting industry of the electric power industry, one of the pillar industries of the national economy, the wire and cable industry plays an extremely important role and position in the national economy. Wire and cable are the key components of power transportation, and the insulating material is one of the key factors that determine the cable's withstand voltage. Due to its good heat resistance and mechanical properties and large transmission capacity, XLPE cables are not only suitable for medium and low voltages, but also can be applied to high and ultra-high voltages. Because of its excellent comprehensive properties, such as good electrical properties, high breakdown electric field strength, small dielectric loss tangent, high insulation resistance; good heat resistance and aging resistance, high allowable operating temperature; large current carrying capacity , suitable for high drop and vertical laying, etc. Cross-linked polyethylene power cables have been paid more and more attention and have become the main material of high-voltage cables in recent years. Studies have shown that the performance of cross-linked polyethylene can be further improved by introducing appropriate other components.

Chinese patent application 201610762167.0 proposes a 220kV cross-linkable polyethylene insulating material with low by-products and a preparation method thereof. By using a formula composed of specific components of low-density polyethylene, antioxidants, cross-linking agents and cross-linking accelerators , can avoid problems such as excessive impurity content and internal pinholes in the obtained product, and can meet the requirements of 220kV cable insulation material manufacturing. However, the mechanical properties of the cross-linked polyethylene cable material are general, the electrical properties such as breakdown strength and high voltage resistance are not outstanding enough, and the application range is narrow.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a high-pressure cross-linked polyethylene cable material and a preparation method thereof. By selecting suitable small molecular compounds to fill, the prepared high-pressure cross-linked polyethylene cable material has excellent mechanical properties, and at the same time further improves the high-pressure cross-linking. The electrical properties such as breakdown strength and high voltage resistance of polyethylene cable materials can effectively expand the application range of cross-linkable polyethylene cable materials.

In order to achieve the above object, the technical scheme created by the present invention is realized like this:

The invention provides a high-pressure cross-linked polyethylene cable material, which is prepared from the following raw materials by weight: 100 parts of polyethylene resin; 0.5-20 parts of cross-linking agent; 0.5-10 parts of antioxidant; 0.1 to 30 parts of small molecular compounds.

Preferably, the small molecule compound is at least one of perfluoropolyether oil, insulating oil, silicone oil or fluorosilicone oil.

Preferably, the perfluoropolyether oil is selected from at least one of K-type, Y-type, Z-type or D-type perfluoropolyether oils.

Preferably, the insulating oil is selected from at least one of transformer oil, capacitor oil, cable oil or switch oil.

Preferably, the transformer oil is selected from at least one of 25# transformer oil, 45# transformer oil, and 10# transformer oil, and the transformer oil is selected from 1,1-phenylxylylethane (PXE), phenylethyl At least one of phenylethane (PEPE) and benzyltoluene blended oil (M/DBT).

Preferably, the silicone oil is selected from the structural formula of

At least one of them, wherein R is alkyl, aryl, R' is alkyl, aryl, hydrogen, carbon functional group or polyether chain; X is alkyl, aryl, alkenyl, hydrogen, hydroxyl, Alkoxy, acetoxy, chlorine, carbofunctional or polyether chains; n, m=0, 1, 2, 3....

Preferably, the fluorosilicone oil is trifluoropropyl vinyl terminated siloxane.

Preferably, the polyethylene resin is ultra-high molecular weight polyethylene (UHMWPE), high density polyethylene (HDPE), low density polyethylene (LDPE), linear low density polyethylene (LLDPE) or ultra low density polyethylene (ULDPE) ) at least one of them.

Preferably, the crosslinking agent is dicumyl peroxide (DCP), benzoyl peroxide (BPO), di-tert-butyl peroxide (DTBA), dicumyl peroxide (DBHP), At least one of diethylenetriamine (DTA) or 2,5-dimethyl-2,5 di-tert-butylperoxide (bis-25).

Preferably, the antioxidant is Antioxidant 1010, Antioxidant 1076, Antioxidant CA, Antioxidant 164, Antioxidant DNP, Antioxidant DLTP, Antioxidant TPP, Antioxidant MB or Antioxidant At least one of the oxygen agents 264.

Preferably, the cross-linking agent is 0.5-5 parts or 5-10 parts or 10-20 parts, more preferably, the cross-linking agent is 0.5-5 parts.

Preferably, the antioxidant is 0.5-4 parts or 4-7 parts or 7-10 parts, more preferably, the antioxidant is 1-4 parts.

Preferably, the small molecule compound is 0.1-10 parts or 10-20 parts or 20-30 parts; more preferably, the small-molecule compound is 10-20 parts.

The present invention also proposes a preparation method of high-pressure cross-linked polyethylene cable material, comprising the following steps:

1) Drying of polyethylene resin;

2) Preparation of pre-dispersed master batch: melt-blending the cross-linking agent, antioxidant, small molecular compound and part of the polyethylene resin after drying in step 1) in an extruder to prepare different pre-dispersed master batches; Among them, the cross-linking agent, antioxidant, small molecular compound and polyethylene resin are proportioned according to the following parts by weight: 100 parts of polyethylene resin; 0.5-40 parts of cross-linking agent; 0.5-20 parts of antioxidant; 0.1 part of small molecular compound ~60 servings;

3) Crushing and drying of the pre-dispersed masterbatch: The pre-dispersed masterbatch obtained in step 2) is crushed and then dried.

4) Preparation of cable material: mix the pre-dispersed masterbatch obtained in step 3) with the remaining polyethylene resin in step 1), add it to a twin-screw extruder, extrude and granulate, and dry to obtain cable material.

Preferably, in step 1), the drying temperature is 60-100° C., and the drying time is 10-24 h.

Preferably, in step 3), the drying temperature is 60-100° C., and the drying time is 8-12 h.

Preferably, the temperature of the extruder is set as follows: the feeding section is 105-135 °C, the compression section is 110-180 °C, the homogenizing section is 110-180 °C, and the die section is 110-180 °C; the rotational speed of the extruder is The setting is: 30-200 r/min; the extrusion process of the extruder adopts air cooling.

Preferably, the temperature of the twin-screw extruder is set to: 105-135°C in the feeding section, 110-180°C in the compression section, 110-180°C in the homogenization section, and 110-180°C in the head part; The rotating speed of the extruder is set as: 30-200 r/min; the extrusion process of the twin-screw extruder adopts air cooling.

Compared with the prior art, the small-molecule compound-filled high-pressure cross-linked polyethylene cable material created by the present invention has the following advantages:

The invention provides a high-pressure cross-linked polyethylene cable material filled with small molecular compounds and a preparation method thereof. The high-pressure cross-linked polyethylene cable material is prepared by filling components such as small molecular compounds. The high-voltage cross-linked polyethylene cable material has excellent mechanical properties. By selecting appropriate small molecular compounds, the electrical properties such as the breakdown strength and high voltage resistance of the high-voltage cross-linked polyethylene cable material can be further improved, which can effectively expand the cross-linked polyethylene cable material. The scope of application of the polyethylene cable material.

Detailed ways

The present invention is further described below with reference to specific embodiments, which are only used to illustrate the present invention and not to limit the protection scope of the present invention.

Example 1

A small molecular compound filling high-pressure cross-linked polyethylene cable material, the pre-dispersed master batch of the cable material is prepared from the raw materials comprising the following parts by weight:

The preparation method of the cable material comprises the following steps:

Step 1): dry all ULDPE in a blast drying oven at 60°C for 12h;

Step 2): Preparation of Pre-dispersed Masterbatch: Melt and blend accurately weighed ULDPE, crosslinking agent, antioxidant 1010 and perfluoropolyether oil in an extruder to obtain a pre-dispersed masterbatch. The temperature of the extruder was set to: 110°C in the feeding section, 115°C in the compression section, 120°C in the homogenization section, and 115°C in the head section; the rotational speed of the extruder was set at 30 r/min.

Step 3): crush the pre-dispersed masterbatch obtained in step 2) and dry it in a blast-type drying oven with a drying temperature of 60°C for 8 hours;

Step 4): preparation of cable material: ULDPE and pre-dispersed masterbatch are proportioned according to the following parts by weight:

100 copies of ULDPE;

50 parts of pre-dispersed masterbatch.

The raw materials are accurately weighed according to the formula, and then added to a twin-screw extruder for extrusion and granulation. The temperature of the twin-screw extruder is set to: 110°C in the feeding section, 115°C in the compression section, and 120°C in the homogenization section. The head part is 115°C; the rotating speed of the extruder is set to: 50r/min. Air cooling is used during extrusion into strands.

Example 2

A small molecular compound filling high-pressure cross-linked polyethylene cable material, the pre-dispersed master batch of the cable material is prepared from the raw materials comprising the following parts by weight:

Step 1): dry all HDPE in a blast drying oven at 80°C for 12h;

Step 2): Preparation of pre-dispersed masterbatch: accurately weighed HDPE, crosslinking agent, antioxidant 1010 and perfluoropolyether oil were melt-blended in an extruder whose temperature was set to : 120 °C in the feeding section, 135 °C in the compression section, 145 °C in the homogenization section, and 140 °C in the head part; the rotating speed of the extruder is set to: 80 r/min.

Step 3): the pre-dispersed masterbatch is crushed and dried for 8h in a blast drying oven with a drying temperature of 60°C;

Step 4): preparation of cable material: HDPE and pre-dispersed master batch are proportioned according to the following weight parts:

100 copies of HDPE;

40 parts of pre-dispersed masterbatch.

The raw materials are accurately weighed according to the formula, and then added to the twin-screw extruder for extrusion and granulation. The partial temperature is 140°C; the rotational speed of the twin-screw extruder is set to: 100r/min. Air cooling is used during extrusion into strands.

Example 3

A small molecular compound filling high-pressure cross-linked polyethylene cable material, the pre-dispersed master batch of the cable material is prepared from the raw materials comprising the following parts by weight:

The composition of ULDPE and pre-dispersed masterbatch in parts by weight:

100 copies of ULDPE;

25 parts of pre-dispersed masterbatch.

Processes such as the preparation of pre-dispersed masterbatch and the extrusion and granulation of cable material are the same as those in Example 1.

Example 4

A small molecular compound filling high-pressure cross-linked polyethylene cable material, the pre-dispersed master batch of the cable material is prepared from the raw materials comprising the following parts by weight:

The composition of HDPE and pre-dispersed masterbatch in parts by weight:

100 copies of HDPE;

100 parts of pre-dispersed masterbatch.

Processes such as the preparation of pre-dispersed masterbatch and the extrusion granulation of cable material are the same as those in Example 2.

Example 5

A small molecule compound filling high-pressure cross-linked polyethylene cable material, the different pre-dispersed master batches of the cable material are prepared from the raw materials comprising the following parts by weight:

Pre-dispersed masterbatch:

Polyethylene resin and pre-dispersed masterbatch are composed according to the following parts by weight:

100 copies of HDPE;

80 parts of pre-dispersed masterbatch.

Processes such as the preparation of pre-dispersed masterbatch and the extrusion granulation of cable material are the same as those in Example 2.

Example 6

A small molecule compound filling high-pressure cross-linked polyethylene cable material, the different pre-dispersed master batches of the cable material are prepared from the raw materials comprising the following parts by weight:

Pre-dispersed masterbatch:

The composition of polyethylene resin and pre-dispersed masterbatch in parts by weight:

100 copies of ULDPE;

30 parts of pre-dispersed masterbatch.

Processes such as the preparation of pre-dispersed masterbatch and the extrusion and granulation of cable material are the same as those in Example 1.

Table 1 shows the performance test results of the cable materials of Examples 1-6.

Table 1

The addition of small molecular compounds is conducive to the uniform dispersion of crosslinking agents and antioxidants, and improves crosslinking efficiency and crosslinking uniformity. Under the action of cross-linking agent, polyethylene becomes a cross-linked polyethylene material with a three-dimensional spatial network structure. Due to the interaction of chemical bonds between polyethylene macromolecular chains, the intermolecular connection is effectively increased, resulting in high molecular weight chains. As the force between them increases, the tensile strength increases. Due to the high gel content of the material, the movement of the chain segments is restricted, the material exhibits brittleness, and the elongation at break decreases. The addition of small molecular compounds plays a lubricating role, reduces the balance torque, improves the processing performance, and at the same time, has a certain effect on improving the mechanical properties of the material. In addition, the addition of small molecular compounds fills the free volume of cross-linked polyethylene, and because of its own insulation, it can effectively reduce the migration rate of carriers and improve the insulation performance of the material.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the within the scope of protection of the present invention.

Claims (1)

1. A perfluoropolyether oil filling high-pressure cross-linked polyethylene cable material, the pre-dispersed master batch of this cable material is prepared by the raw material of following parts by weight: 100 copies of ULDPE; 4.5 parts of cross-linking agent; Antioxidant 1010 3 copies; 9 parts of perfluoropolyether oil; The preparation method of the cable material comprises the following steps: Step 1): Dry all ULDPE in a blast drying oven at 60°C for 12h; Step 2): Preparation of Pre-dispersed Masterbatch: Melt and blend accurately weighed ULDPE, cross-linking agent, antioxidant 1010 and perfluoropolyether oil in an extruder to obtain a pre-dispersed masterbatch; The temperature of the extruder is set to: 110 °C in the feeding section, 115 °C in the compression section, 120 °C in the homogenization section, and 115 °C in the head part; the rotational speed of the extruder is set to: 30 r/min; Step 3): crush the pre-dispersed masterbatch obtained in step 2) and dry it for 8 hours in a blast drying oven with a drying temperature of 60°C; Step 4): Preparation of cable material: The ULDPE obtained in step 1) and the pre-dispersed masterbatch obtained in step 3) are proportioned according to the following parts by weight: 100 copies of ULDPE; 50 parts of pre-dispersed masterbatch; The raw materials are accurately weighed according to the formula, and then added to a twin-screw extruder for extrusion and granulation. The temperature of the twin-screw extruder is set to: 110°C in the feeding section, 115°C in the compression section, and 120°C in the homogenization section. The head part is 115°C; the rotating speed of the extruder is set to: 50r/min; air cooling is adopted during the extrusion process.