阅读说明：本技术 一种防冻聚乙烯电力管及其制备方法 (Anti-freezing polyethylene power tube and preparation method thereof ) 是由 陈毅明 孙东华 裘杨燕 傅亚斌 齐国良 于 2020-03-24 设计创作，主要内容包括：本发明属于电力防护管道技术领域,具体涉及一种防冻聚乙烯电力管及其制备方法,包括碳纳米管改性高密度高密度聚乙烯10-12份、高密度高密度聚乙烯88-90份、增韧剂3-5份、填充剂3-5份、偶联剂6-8份、增塑剂1-2份和架桥剂1-2份；制备时将碳纳米管改性高密度高密度聚乙烯、高密度聚乙烯、碱式硫酸镁晶须、KH550硅烷、丙烯酸酯橡胶、二氧化硅、马来酸二辛酯和三甲基六亚甲基二胺搅拌反应得到熔融液；再置入双螺杆挤出机,其中进料段温度控制在100-110℃,连接体温度控制在150-160℃,口模温度控制在220-260℃,芯模模温机温度控制在195-205℃,挤出速度为1.0-1.6m/min,得到电力管。本发明不仅能够具有良好的耐低温性能,并且具有较强的抗冲击强度、拉伸强度和断裂伸长率等力学性能。(The invention belongs to the technical field of electric power protection pipelines, and particularly relates to an anti-freezing polyethylene electric power tube and a preparation method thereof, wherein the anti-freezing polyethylene electric power tube comprises 10-12 parts of carbon nano tube modified high-density polyethylene, 88-90 parts of high-density polyethylene, 3-5 parts of a toughening agent, 3-5 parts of a filler, 6-8 parts of a coupling agent, 1-2 parts of a plasticizer and 1-2 parts of a bridging agent; during preparation, carbon nano tube modified high-density polyethylene, basic magnesium sulfate whisker, KH550 silane, acrylate rubber, silicon dioxide, dioctyl maleate and trimethyl hexamethylene diamine are stirred to react to obtain molten liquid; then placing the mixture into a double-screw extruder, wherein the temperature of the feeding section is controlled to be 110-. The invention not only has good low temperature resistance, but also has strong mechanical properties such as impact strength, tensile strength, elongation at break and the like.)

1. The utility model provides an anti-freezing polyethylene power tube which characterized in that: the composite material comprises the following raw materials in parts by weight: 10-12 parts of carbon nano tube modified high-density polyethylene, 88-90 parts of high-density polyethylene, 3-5 parts of toughening agent, 3-5 parts of filler, 6-8 parts of coupling agent, 1-2 parts of plasticizer and 1-2 parts of bridging agent.

2. The antifreeze polyethylene power pipe of claim 1, wherein: the toughening agent is acrylate rubber, the filling agent is silicon dioxide, the coupling agent is KH550 silane, the plasticizer is dioctyl maleate, and the bridging agent is trimethyl hexamethylene diamine.

3. The antifreeze polyethylene power pipe of claim 2, wherein: the raw materials of the antifreezing polyethylene power tube also comprise 5-8 parts of basic magnesium sulfate whisker.

4. The antifreeze polyethylene power pipe of claim 3, wherein: the anti-freezing polyethylene power tube comprises, by mass, 11 parts of carbon nanotube modified high-density polyethylene, 89 parts of high-density polyethylene, 6.5 parts of basic magnesium sulfate whisker, 4 parts of acrylate rubber, 4 parts of silicon dioxide, 7 parts of a coupling agent, 1.5 parts of dioctyl maleate and 1.5 parts of trimethylhexamethylene diamine.

5. The method for preparing the antifreeze polyethylene power tube as claimed in claim 3, wherein the method comprises the following steps: comprises the following steps of (a) carrying out,

a1, melting the carbon nano tube modified high-density polyethylene, the basic magnesium sulfate whisker and the KH550 silane at the temperature of 100-120 ℃, fully and uniformly stirring, and reacting for 30-40min under the stirring state;

a2, adding acrylate rubber, silicon dioxide, dioctyl maleate and trimethyl hexamethylene diamine at the temperature of 100-120 ℃, and stirring for reaction for 20-30min to obtain molten liquid;

a3, placing the molten liquid into a double-screw extruder, wherein the temperature of a feeding section of the double-screw extruder is controlled to be 110 ℃ plus 100 ℃, the temperature of a connecting body is controlled to be 160 ℃ plus 150 ℃, the temperature of a neck mold is controlled to be 260 ℃ plus 220 ℃, the temperature of a core mold temperature machine is controlled to be 205 ℃ plus 195 ℃, and the extrusion speed is 1.0-1.6m/min, so as to obtain the power tube.

6. The method for preparing the antifreeze polyethylene power tube as claimed in claim 5, wherein the method comprises the following steps: the preparation method of the carbon nano tube modified high-density polyethylene comprises the following steps:

b1, according to the mass parts, taking 10 parts of carbon nanotubes, and dispersing the carbon nanotubes in a solvent with the volume ratio of 3: 1, treating the mixed solution by 20-25 parts of mixed solution of 98% concentrated sulfuric acid and 68% concentrated nitric acid in a stirring state for 10-12 hours, filtering and cleaning to obtain the cut carbon nano tube with carboxyl;

b2 heating 100 parts of high-density polyethylene to 100-120 ℃, adding the carbon nano tube cut in the step B1 after the high-density polyethylene is completely melted, fully and uniformly stirring, adding 10-20 parts of potassium permanganate powder, and stirring and reacting for 30-40 min;

and B3, cooling and granulating the reaction product of B2 to obtain the carbon nano tube modified high-density polyethylene.

7. The method for preparing the antifreeze polyethylene power tube as claimed in claim 6, wherein the method comprises the following steps: in step B1, when the carbon nanotubes are reacted in 98% concentrated sulfuric acid and 68% concentrated nitric acid, ultrasonic wave is used for oscillation, the ultrasonic wave frequency is 20000- & ltwb00 & gtHZ, and the reaction time is 2-3 hours.

8. The method for preparing the antifreeze polyethylene power tube as claimed in claim 7, wherein the method comprises the following steps: in the step B2, after the reaction is finished, 0.2-0.4 part of trimethyl tin is added and stirred uniformly.

Technical Field

The invention belongs to the technical field of electric power protection pipelines, and particularly relates to an anti-freezing polyethylene electric power pipe and a preparation method thereof.

Background

The current electric power tube is a product which is subjected to hot dip coating by PE (modified polyethylene) or is coated with epoxy resin inside and outside, and has excellent corrosion resistance. Meanwhile, the coating has good electrical insulation and can not generate electric corrosion. Low water absorption, high mechanical strength and small friction coefficient, and can achieve the purpose of long-term use. And can also effectively prevent the damage of the plant root system and the soil environmental stress, and the like.

The electric power pipe adopts the formula pipe laying of burying more, and need weld the electric power pipe, needs natural cooling after the welding is accomplished, and because of the winter temperature is lower, natural cooling is very fast, freezes the pipeline easily. In addition, the power tube is more brittle and hard in winter than in summer, if the power tube is easily broken due to violent loading and unloading, the internal cable cannot be protected in time, and loss is caused, so that the anti-freezing performance of the power tube is particularly important.

The patent with the application number of CN201510666712.1 discloses a low-temperature-resistant high-density polyethylene power cable protection tube, which comprises high-density polyethylene, a toughening agent, a filler, a coupling agent, a plasticizer and a bridging agent, wherein the toughening agent is liquid acrylate rubber, the filler is mica powder, the coupling agent is gamma-mercaptopropyltriethoxysilane, the plasticizer is dioctyl maleate, and the bridging agent is trimethylhexamethylenediamine.

Although the high-density polyethylene, the toughening agent, the filler, the coupling agent, the plasticizer and the bridging agent in the patent scheme enable the produced power cable protection pipe to have the characteristics of good low temperature resistance and long service life; but also has the following disadvantages: the high-density polyethylene used by the method has the defects of low toughness, low hardness, poor environmental stress cracking energy and the like, and is used for burying the power pipe underground, and if the ground is pressed by a heavy vehicle, the impact strength of the power pipe cannot meet the requirement.

Disclosure of Invention

The invention aims to provide an antifreezing polyethylene electric power tube and a preparation method thereof, which not only have good low-temperature resistance, but also have stronger mechanical properties such as impact strength, tensile strength, elongation at break and the like.

In order to achieve the technical purpose, the technical scheme adopted by the invention is as follows:

an anti-freezing high-density polyethylene power tube comprises, by mass, 10-12 parts of carbon nanotube-modified high-density polyethylene, 88-90 parts of high-density polyethylene, 3-5 parts of a toughening agent, 3-5 parts of a filler, 6-8 parts of a coupling agent, 1-2 parts of a plasticizer and 1-2 parts of a bridging agent.

Further, the toughening agent is acrylate rubber, the filler is silicon dioxide, the coupling agent is KH550 silane, the plasticizer is dioctyl maleate, and the bridging agent is trimethyl hexamethylene diamine.

Further, the raw material of the anti-freezing polyethylene power tube also comprises 5-8 parts of basic magnesium sulfate whisker. The basic magnesium sulfate whisker has a single crystal structure and is needle-shaped or fibrous, can change the crystallization behavior of high-density polyethylene when added into the high-density polyethylene, has a relatively obvious reinforcing effect on the high-density polyethylene, has a small self-expansion coefficient, and can also play a filling role, and can be arranged along the flow direction of a melt after being filled into the high-density polyethylene, so that the linear expansion coefficient of the high-density polyethylene composite material is favorably reduced, and the mechanical property of the high-density polyethylene is enhanced.

Further, the anti-freezing polyethylene power tube comprises, by mass, 11 parts of carbon nanotube-modified high-density polyethylene, 89 parts of high-density polyethylene, 6.5 parts of basic magnesium sulfate whisker, 4 parts of acrylate rubber, 4 parts of silicon dioxide, 7 parts of KH550 silane, 1.5 parts of dioctyl maleate and 1.5 parts of trimethylhexamethylene diamine.

The invention also discloses a preparation method of the anti-freezing high-density polyethylene power tube, which comprises the following steps:

a1, melting the carbon nano tube modified high-density polyethylene, the basic magnesium sulfate whisker and the KH550 silane at the temperature of 100-120 ℃, fully and uniformly stirring, and reacting for 30-40min under a stirring state; KH550 silane coupling agent and high-density polyethylene are subjected to silane crosslinking reaction, so that the mechanical property of the high-density polyethylene is enhanced.

A2, adding acrylate rubber, silicon dioxide, dioctyl maleate and trimethyl hexamethylene diamine at the temperature of 100-120 ℃, and stirring for reaction for 20-30min to obtain molten liquid;

a3, placing the molten liquid into a double-screw extruder, wherein the temperature of a feeding section of the double-screw extruder is controlled to be 110 ℃ plus 100 ℃, the temperature of a connecting body is controlled to be 160 ℃ plus 150 ℃, the temperature of a neck mold is controlled to be 260 ℃ plus 220 ℃, the temperature of a core mold temperature machine is controlled to be 205 ℃ plus 195 ℃, and the extrusion speed is 1.0-1.6m/min, so as to obtain the power tube.

Further, the preparation method of the carbon nanotube modified high-density polyethylene comprises the following steps:

b1, according to the mass parts, taking 10 parts of carbon nanotubes, and dispersing the carbon nanotubes in a solvent with the volume ratio of 3: 1, treating the mixed solution by 20-25 parts of mixed solution of 98% concentrated sulfuric acid and 68% concentrated nitric acid in a stirring state for 10-12 hours, filtering and cleaning to obtain the cut carbon nano tube with carboxyl;

b2 heating 100 parts of high-density polyethylene to 100-120 ℃, adding the carbon nano tube cut in the step B1 after the high-density polyethylene is completely melted, fully and uniformly stirring, adding 10-20 parts of potassium permanganate powder, and stirring and reacting for 30-40 min;

and B3, cooling and granulating the reaction product of B2 to obtain the carbon nano tube modified high-density polyethylene.

The oxidation of carbon nanotube (SWNT) in concentrated sulfuric acid and concentrated nitric acid produces SWNT-COOH, which reacts with high density polyethylene under the strong oxidation of potassium permanganate to make the-OH of SWNT-COOH react with the-H of high density polyethylene to obtain high density polyethylene grafted with "SWNT-CO-".

Further, in step B1, when the carbon nanotubes are reacted in 98% concentrated sulfuric acid and 68% concentrated nitric acid, ultrasonic waves are used for oscillation, the ultrasonic frequency is 20000-30000HZ, and the reaction time is 2-3 hours. Under the oscillation of ultrasonic waves, the reaction time can be reduced, and the reaction fullness can also be increased.

Further, in the step B2, after the reaction is completed, 0.2 to 0.4 part of trimethyltin is further added and stirred uniformly. The addition of the trimethyltin can enhance the chemical stability of the carbon nanotube modified high-density polyethylene in a high-temperature state, avoid the bond fracture of the high-density polyethylene and the carbon nanotube in a cooling stage, stabilize the chemical bond in the processes of cooling and heating in the production of the power tube and ensure the mechanical strength of the power tube.

The invention has the following beneficial effects:

1. according to the invention, the carbon nanotube modified high-density polyethylene is introduced into the high-density polyethylene power tube, wherein the carbon nanotube modified high-density polyethylene accounts for about 10% of the whole high-density polyethylene, and the carbon nanotube group is added into the carbon nanotube modified high-density polyethylene through a grafting reaction, so that the introduction of the carbon nanotube group greatly increases the mechanical properties of the power tube, such as impact strength, tensile strength, elongation at break and the like, and the produced power tube can meet the requirements of low temperature resistance and mechanical properties of the power tube.

2. The carbon nanotube modified high-density polyethylene is prepared by grafting carboxyl on the carbon nanotube, then reacting with the high-density polyethylene, grafting a carbon nanotube group on the high-density polyethylene, and adding trimethyltin for protecting chemical bonds after cooling, so that the damage to the chemical bonds in the production of the power tube is avoided, and the mechanical property of the power tube can be better ensured.

3. When the power tube is prepared, the basic magnesium sulfate whisker is added, so that the effect of filling and changing high-density polyvinyl chloride can be achieved, and the mechanical property of the power tube is improved; KH550 silane is used as a coupling agent, and the coupling agent and the high-density polyethylene are subjected to silane crosslinking reaction, so that the mechanical property of the high-density polyethylene is enhanced.

Detailed Description

In order that those skilled in the art can better understand the present invention, the following embodiments are further described.