A kind of ageing-resistant polypropylene cable insulation formula technology

Abstract

The present invention proposes a design of an aging-resistant polypropylene cable insulation formula, which belongs to the field of electrical material synthesis and preparation. In terms of mass fractions, the cable insulation material includes 70-90 parts of polypropylene, 10-20 parts of polymer elastomer, 1-3 parts of voltage stabilizer, and 0.1-0.2 parts of lubricant. Among them, the voltage stabilizer is oleic acid amide. The present invention proposes to mix polypropylene and polymer elastomer uniformly, obtain a blended masterbatch after melt blending, extrusion, cooling, drying, and pelletizing, and then melt extrude the blended masterbatch after mixing with the polymer elastomer to obtain a long-aging resistant polypropylene cable insulation material.

Description

Technical Field

[0001] The invention provides a method for preparing an aging-resistant polypropylene cable insulation formula, which has a service life of more than 25 years at a long-term use temperature of 90 DEG C and belongs to the technical field of electrical materials. Background Art

[0002] Polypropylene has excellent electrical insulation properties and high heat resistance, as well as high mechanical strength and good chemical corrosion resistance. It stands out in the research and development of non-cross-linked high-voltage DC cable materials and represents the development direction of power cables today. However, due to its poor flexibility at room temperature and the easy accumulation of space charges under the action of high-voltage electric fields, single polypropylene cannot be directly used in high-voltage DC cables. Modification of polypropylene becomes particularly important and is a hot topic in current research.

[0003] The performance of polypropylene depends on its structure. As we all know, the multi-layer structure is the basic characteristic of polymers, and the change of each layer structure provides the possibility of improving its performance.

[0004] The copolymerization modification of polypropylene is mainly based on propylene monomer, and other monomers (one or more) are added during the polymerization stage using high-efficiency catalysts to make them co-polymerized. Depending on the polymerization method, block copolymers, alternating copolymers and random copolymers can be obtained.

[0005] As the importance of polypropylene cables becomes increasingly prominent, it is imperative to develop new technologies with simple processes, convenient operations, and aging resistance. The implementation of this patent has important theoretical and practical significance for promoting the application of polypropylene cables. At the same time, it can promote the structural adjustment of the traditional cable industry. Summary of the invention

[0006] In order to improve the aging resistance of polypropylene cables, the present invention provides an aging-resistant polypropylene cable insulation formula, which includes 70 to 90 parts of polypropylene, 10 to 20 parts of polymer elastomer, 1 to 3 parts of voltage stabilizer, and 0.1-0.2 parts of lubricant in parts by mass.

[0007] The present invention also proposes a method for preparing an aging-resistant polypropylene cable insulation material, which comprises at least the following steps:

[0008] Preparation of blending masterbatch: the voltage stabilizer and polypropylene are mixed at a high speed of 1500-1800 r / min for 20-30 min, the obtained blend is melt-blended and extruded in an extruder at 200-250° C., and pelletized after cooling and drying to obtain blending masterbatch;

[0009] Preparation of aging-resistant polypropylene cable insulation material: the blended masterbatch and the polymer elastomer are mixed at a high speed of 1500-1800r / min for 20-30min, and then placed in a wire and cable extruder at a temperature of 200-250°C for melt extrusion, and then cooled and solidified, while adjusting the take-up speed of the traction machine to control the shrinkage rate of the insulation material, and then dried and pelletized to obtain the aging-resistant polypropylene cable insulation material. DETAILED DESCRIPTION

[0010] Example 1

[0011] Preparation of blended masterbatch: 1g voltage stabilizer and 85g polypropylene are mixed at a high speed of 1500-1800r / min for 20-30min, the obtained blend is melt-blended and extruded in an extruder at 200-250°C, cooled and dried, and then pelletized to obtain blended masterbatch;

[0012] Preparation of aging-resistant polypropylene cable insulation material: 86g of blended masterbatch and 14g of ethylene-propylene rubber are mixed at a high speed of 1500-1800r / min for 20-30min, and then placed in a wire and cable extruder at a temperature of 200-250°C for melt extrusion, followed by cooling and curing, while adjusting the take-up speed of the traction machine to control the shrinkage rate of the insulation material, and then dried and pelletized to obtain the aging-resistant polypropylene cable insulation material.

[0013] Example 2

[0014] Preparation of blended masterbatch: 3g voltage stabilizer and 75g polypropylene are mixed at a high speed of 1500-1800r / min for 20-30min, the obtained blend is melt-blended and extruded in an extruder at 200-250°C, and pelletized after cooling and drying to obtain blended masterbatch;

[0015] Preparation of aging-resistant polypropylene cable insulation material: 78g of blended masterbatch and 22g of butadiene rubber are mixed at a high speed of 1500-1800r / min for 20-30min, and then placed in a wire and cable extruder at a temperature of 200-250°C for melt extrusion, followed by cooling and curing, while adjusting the take-up speed of the traction machine to control the shrinkage rate of the insulation material, and then drying and pelletizing to obtain the aging-resistant polypropylene cable insulation material.

[0016] Example 3

[0017] Preparation of blended masterbatch: 1g voltage stabilizer and 70g polypropylene are mixed at a high speed of 1500-1800r / min for 20-30min, the obtained blend is melt-blended and extruded in an extruder at 200-250°C, cooled and dried, and then pelletized to obtain blended masterbatch;

[0018] Preparation of aging-resistant polypropylene cable insulation material: 71g of blended masterbatch and 29g of styrene-butadiene-styrene are mixed at a high speed of 1500-1800r / min for 20-30min, and then placed in a wire and cable extruder at a temperature of 200-250°C for melt extrusion, followed by cooling and curing, while adjusting the take-up speed of the traction machine to control the shrinkage rate of the insulation material, and then drying and pelletizing to obtain the aging-resistant polypropylene cable insulation material.

[0019] Example 4

[0020] Preparation of blended masterbatch: 3g voltage stabilizer and 90g polypropylene are mixed at a high speed of 1500-1800r / min for 20-30min, the obtained blend is melt-blended and extruded in an extruder at 200-250°C, cooled and dried, and then pelletized to obtain blended masterbatch;

[0021] Preparation of aging-resistant polypropylene cable insulation material: 93g of blended masterbatch and 7g of polyolefin are mixed at a high speed of 1500-1800r / min for 20-30min, and then placed in a wire and cable extruder at a temperature of 200-250°C for melt extrusion, followed by cooling and curing, while adjusting the take-up speed of the traction machine to control the shrinkage rate of the insulation material, and then dried and pelletized to obtain the aging-resistant polypropylene cable insulation material.

Claims

1. The present invention aims to develop a method for preparing an ageing-resistant polypropylene cable insulation formula, which has a service life of more than 25 years at a long-term use temperature of 90°C, characterized in that: Calculated by weight, the cable insulation material comprises 70-90 parts of polypropylene, 10-20 parts of polymer elastomer, 1-3 parts of voltage stabilizer, and 0.1-0.2 parts of lubricant.

2. The aging-resistant polypropylene cable insulation material according to claim 1, characterized in that: The polypropylene has a melting point of 145-160°C, a density of 0.707 g / cm3, and a melt index of 200°C / 1.57kg.

3. The aging-resistant polypropylene cable insulation material according to claim 1, characterized in that: The voltage stabilizer is oleamide.

4. The aging-resistant polypropylene cable insulation material according to claim 1, characterized in that: The polymer elastomer is one or more mixtures of ethylene-propylene rubber, butadiene rubber, polyolefin, and styrene-butadiene-styrene.