CN115232384B

CN115232384B - Antistatic PE gas pipe and preparation method thereof

Info

Publication number: CN115232384B
Application number: CN202211025120.8A
Authority: CN
Inventors: 于常军; 崔东明; 张群甲
Original assignee: Qingdao U Pipe Environmental Protection Technology Co ltd
Current assignee: Qingdao U Pipe Environmental Protection Technology Co ltd
Priority date: 2022-08-25
Filing date: 2022-08-25
Publication date: 2023-02-10
Anticipated expiration: 2042-08-25
Also published as: CN115232384A

Abstract

The application relates to the technical field of gas pipes, and particularly discloses an antistatic PE gas pipe and a preparation method thereof. The paint comprises the following components in parts by weight: 90-100 parts of polyethylene, 3.5-7 parts of antistatic master batch, 4-8 parts of flame retardant, 5-9 parts of anti-aging agent, 30-35 parts of aramid fiber and 15-20 parts of carbon black; the antistatic master batch comprises the following components in parts by weight: 4-5 parts of high-density polyethylene, 0.3-0.5 part of graphene oxide, 1-2 parts of carbon fiber, 10-15 parts of deionized water and 1-2 parts of long-acting antistatic agent. The utility model provides an antistatic PE gas pipe has that antistatic effect is strong, and antistatic effect is lasting, and when root hot melt connection is pursued, hot melt department tensile strength is high, difficult cracked advantage.

Description

Antistatic PE gas pipe and preparation method thereof

Technical Field

The application relates to the technical field of gas pipes, in particular to an antistatic PE gas pipe and a preparation method thereof.

Background

With the continuous acceleration of the urbanization process, the number of urban residents is increasing day by day, and the requirements on municipal infrastructure such as gas engineering and the like are also continuously improved. The gas pipe is used as a special pipeline for conveying combustible gas, and has the characteristics of convenient installation, reliable connection, corrosion resistance, no gas blockage, good flexibility, long service life, free bending without deformation and the like, and the strong development of the polyethylene pipe is most attractive.

The existing polyethylene gas pipe is obtained by adding PE master batch, an antioxidant, a flame retardant and the like into an extruder, spraying, cooling and cutting at a fixed length. The polyethylene has high resistance per se, and can reach 10 ¹⁰ -10 ²⁰ Ohm, when used as a gas pipe, the gas rubs with the pipe, and is easy to collect on the pipeThe static electricity is gathered, if the gathered static electricity can not be led out in time, explosion is easy to generate, therefore, when the polyethylene gas pipe is prepared, the antistatic agent is generally added into the polyethylene body in a mixing mode, the antistatic agent mixed in the polyethylene body can make up the loss of the antistatic agent on the inner wall of the pipe through migration, and the antistatic effect is more durable. However, the antistatic agent is mixed into the pipe, and the compatibility of the antistatic agent and a polyethylene matrix is regulated, controlled and controlled, because if the compatibility is too strong, the antistatic agent in the polyethylene pipe cannot timely supplement the loss of the inner wall of the pipe, so that the antistatic effect cannot be achieved, and the compatibility is too weak, so that the antistatic agent is easy to accumulate on the inner wall of the polyethylene pipe, the loss is accelerated, and the durable antistatic effect cannot be achieved.

In view of the above-mentioned related art, the inventors found that when the antistatic agent is added to the polyethylene pipe in a mixing manner, the antistatic effect of the inner wall of the pipe, which is rubbed with gas, is difficult to control, and the initial antistatic effect and the durability of the antistatic property are not good.

Disclosure of Invention

In order to improve the antistatic effect and the antistatic durability of a polyethylene gas pipe, the application provides an antistatic PE gas pipe and a preparation method thereof.

In a first aspect, the application provides an antistatic PE gas pipe, which adopts the following technical scheme:

an antistatic PE gas pipe comprises the following components in parts by weight: 90-100 parts of polyethylene, 3.5-7 parts of antistatic master batch, 4-8 parts of flame retardant, 5-9 parts of anti-aging agent, 30-35 parts of aramid fiber and 15-20 parts of carbon black;

the antistatic master batch comprises the following components in parts by weight: 4-5 parts of high-density polyethylene, 0.3-0.5 part of graphene oxide, 1-2 parts of carbon fiber, 10-15 parts of deionized water and 1-2 parts of long-acting antistatic agent.

By adopting the technical scheme, the aramid fiber is a high-performance synthetic fiber, not only has higher strength and toughness, but also has the advantages of high elastic modulus, high temperature resistance, acid and alkali resistance, low density and good thermal stability, and can be used as a reinforcing material to prevent the mechanical property reduction of polyethylene master batches due to the doping of carbon black and an anti-aging agent because of poor compatibility; in addition, the high-density polyethylene is used as a main material in the antistatic master batch, the high-density polyethylene can be used as compatibility, the compatibility of the rest components in the antistatic master batch with the polyethylene is improved, the graphene oxide contains hydroxyl and epoxide functional groups, carbonyl and carboxyl are contained at the edge of the graphene oxide, the graphene oxide has good solubility, the graphene oxide is very easy to combine with carbon fibers, although the graphene oxide does not have conductivity, the graphene oxide has excellent conductivity, and after the graphene oxide is reduced, a conductive sheet layer is formed on the surface of the carbon fibers loaded with the graphene, so that the dissipation of accumulated charges on the surface of the polyethylene is accelerated, and the pipe achieves the antistatic effect; carbon fiber surface load's graphite alkene layer self-assembly, the antistatic properties of carbon fiber has been showing and has been improved, make the surface resistivity of carbon fiber reduce, graphite alkene forms the conducting network on carbon fiber surface, and carbon fiber is the fibre that has good conductivity, carbon fiber can form the electrically conductive route in the mutual overlap joint of tubular product, thereby make the surface resistivity of gas pipe reduce, utilize the form with the better antistatic master batch of polyethylene compatibility, the component that will have antistatic function is doped into the gas pipe, can improve the gathering of carbon fiber in the polyethylene gas pipe, improve the dispersion degree of consistency, improve antistatic effect and persistence.

When the end hot melting connection of the two pipes is carried out, the carbon fibers at the ends of the pipes are still in a fiber state, and when the end hot melting connection of the two pipes is carried out, the carbon fibers at the ends of the two pipes can be mutually overlapped, so that the tensile strength of the hot melting connection position of the pipes is increased.

Optionally, the antistatic master batch is prepared by the following method:

mixing graphene oxide with deionized water to prepare graphene oxide dispersion liquid;

soaking carbon fibers in the graphene oxide dispersion liquid, heating to 80-90 ℃, soaking for 20-48h, drying, hot-pressing and reducing to obtain graphene modified carbon fibers;

and drying the high-density polyethylene, mixing with the long-acting antistatic agent and the graphene modified carbon fiber, dispersing, melting and granulating to obtain the antistatic master batch.

By adopting the technical scheme, the carbon fibers are soaked in the graphene oxide dispersion liquid, graphene oxide is loaded on the surfaces of the carbon fibers, after drying and hot pressing, the graphene oxide is mutually lapped on the surfaces of the carbon fibers to form a network structure, the graphene oxide is reduced into graphene after reduction, the lattice structures are orderly arranged, a large number of oxygen-containing groups are removed, the graphene is self-assembled on the surfaces of the carbon fibers to improve the antistatic performance of the carbon fibers, then the graphene modified carbon fibers, high-density polyethylene and a long-acting antistatic agent are blended to prepare the antistatic master batch, and the antistatic master batch is fully and uniformly dispersed in the pipes when the gas pipes are extruded and manufactured, so that a better antistatic effect is formed.

Optionally, the hot pressing temperature is 120-150 ℃, and the pressure is 0.4-0.8MPa.

By adopting the technical scheme, hot pressing is carried out before graphene oxide is reduced into graphene, so that a more compact and continuous conductive net structure can be formed on the surface of carbon fiber, and the conductivity is enhanced.

Optionally, the reduction method is selected from one of ultraviolet reduction and dopamine reduction.

By adopting the technical scheme, the reaction speed of ultraviolet light irradiation reduction is high, and the reduction time is short; the dopamine reduction method can reduce graphene oxide, increase the bonding effect between high-density polyethylene and carbon fibers, improve the interface bonding strength of the high-density polyethylene and the carbon fibers, and improve the tensile strength of a welded junction of two gas pipes during hot-melt connection.

Optionally, the specific method for reducing dopamine comprises: dissolving Tris (hydroxymethyl) aminomethane with deionized water, adjusting pH to 8-8.5 to prepare a Tris solution, and preparing a dopamine solution by using the Tris solution;

and adding the hot-pressed carbon fiber into a dopamine solution, soaking for 20-24h at room temperature, washing with deionized water, and drying.

By adopting the technical scheme, the dopamine solution contains hydroxyl and amino, so that the interface wettability between the carbon fiber and the high-density polyethylene can be improved, and the dopamine solution is tender and adhered to the surface of the high-density polyethylene through strong interaction, so that the adhesive force of the carbon fiber and the high-density polyethylene is further improved, the mechanical strength of the antistatic master batch is improved, and the mechanical effect of the gas pipe is further improved.

Optionally, the ultraviolet light reduction method includes adding a reducing agent into the graphene oxide dispersion liquid, where the reducing agent is hydrazine hydrate with a mass concentration of 1-1.5%, and a mass ratio of the reducing agent to the graphene oxide is 1-2.

By adopting the technical scheme, hydrazine hydrate is used as a reducing agent of the graphene oxide and is reduced by cooperating with ultraviolet rays, so that oxygen-containing functional groups can be rapidly removed from the graphene oxide, and the reduction time is shortened.

Optionally, the long-acting antistatic agent is polyethylene wax grafted sodium acrylate.

By adopting the technical scheme, the polyethylene wax has good compatibility with polyethylene, and after the sodium acrylate with the antistatic function is grafted on the polyethylene wax, the sodium acrylate can be uniformly dispersed in a matrix in a micron-sized sheet or particle form, and the electric charge can be circulated by forming a conductive network structure in the polyethylene, so that the antistatic master batch with the long-acting antistatic effect is prepared, the gas pipe has lower surface resistivity, and a better antistatic effect is obtained.

Optionally, the aramid fiber is pretreated by:

carrying out chemical silver plating on the surface of the aramid fiber to prepare silver-plated aramid fiber;

adding the silver-plated aramid fiber into an absolute ethanol solution, adding thioglycolic acid, reacting at room temperature in a nitrogen atmosphere in a dark place for 20-24 hours, centrifuging, and washing to prepare the carboxylated nano silver aramid fiber;

mixing polyvinylidene fluoride particles with 1, 4-butanediamine solution and sodium carbonate, soaking at room temperature for 12-16h, centrifuging, washing and drying to obtain aminated polyvinylidene fluoride;

dispersing the carboxylated nano-silver aramid fiber in an absolute ethanol solution, adding the aminated polyvinylidene fluoride, mixing, continuously reacting for 24-28h at room temperature in a nitrogen atmosphere, washing, centrifuging, drying, and melting and granulating.

By adopting the technical scheme, the aramid fiber has smooth surface and poor surface wettability, when the aramid fiber is compounded with polyvinylidene fluoride, the bonding strength of two phase interfaces is weaker, the silver coating is arranged on the aramid fiber, the bonding force of the interface of the aramid fiber and the polyvinylidene fluoride can be improved, and the aramid fiber has conductive performance because the conductive performance of all fillers is the best, and then the silver coating on the surface of the aramid fiber is coated by thioglycolic acid, so that carboxyl is introduced on the silver coating, the surface functionalization is carried out on the silver coating, the silver-coated aramid fiber is uniformly distributed in the pipe, and the silver-coated aramid fiber is uniformly distributed in the pipe matrix, so that a complete, uniform and effective conductive network is formed for enhancing the antistatic performance of the pipe; polyvinylidene fluoride is thermoplastic resin, has excellent performances such as chemical corrosion resistance, high mechanical strength and the like, is grafted by amino through 1, 4-butanediamine, and then is subjected to amidation reaction with aminated polyvinylidene fluoride and carboxylated silver-plated aramid fiber to form a chemical bond on the interface of the composite material, so that the interface combination of the aramid fiber and the polyvinylidene fluoride is enhanced, and the performance of the composite material is improved; in addition, the polyvinylidene fluoride is thermoplastic fluororesin, and can be hot-melted when the pipes are hot-melted and connected, so that the hot-melting bonding strength of the connecting ports is increased, and the connecting force at the connecting ports is increased.

Optionally, the flame retardant is selected from one of magnesium hydroxide, aluminum hydroxide and organic bromide;

the anti-aging agent comprises dibutyl hydroxy toluene, butyl hydroxy anisole and tert-butyl hydroquinone in a mass ratio of 1.8-1.

In a second aspect, the application provides a preparation method of an antistatic PE gas pipe, which adopts the following technical scheme: the preparation method of the antistatic PE gas pipe comprises the following steps:

drying carbon black and polyethylene at 75-85 deg.C for 3-5 hr;

uniformly mixing the dried polyethylene and carbon black with the antistatic master batch, the anti-aging agent, the flame retardant and the aramid fiber to obtain a mixture;

preheating a machine barrel, and performing extrusion molding on the mixture to obtain a tubular gas pipe;

and sequentially carrying out vacuum shaping, spray cooling, marking printing and traction cutting on the gas pipe to obtain a finished product.

By adopting the technical scheme, because the carbon black component has strong water absorption, the carbon black and polyethylene are dried before production, and then are sequentially mixed, extruded, shaped, cooled and the like, so that the prepared gas pipe has high mechanical strength, the welded junction is tightly bonded, and the gas pipe is not easy to break.

Optionally, the preheating of the cylinder is divided into three stages, wherein the first stage is heating to 130 ℃, the temperature is kept for 1-3h, the second stage is heating to 180 ℃, the temperature is kept for 1-2h, and the third stage is heating to 180-220 DEG C

By adopting the technical scheme, the defects of raw material deterioration, carbonization and the like caused by overhigh heating temperature and overlong time of the raw material can be overcome by heating in sections.

Optionally, the temperature of the cooling water is 15-25 ℃.

Through adopting above-mentioned technical scheme, the cooling water temperature is too high, the temperature difference of gas pipe and cooling water is on the low side, the cooling efficiency reduces or obtains the required cooling time of same cooling effect long in unit cooling time, it is long to mean that the gas pipe surface is in the time of high temperature, especially the tubular product inner wall, can accelerate the decomposition of additives such as anti-aging in the raw materials like this, reduce the ageing resistance performance of tubular product, also have adverse effect to the cooling crystallization of tubular product equally, cooling water temperature is low excessively on the contrary, then can make the gas pipe surface cooling crystallization rate too fast, cause the inside and outside surface temperature difference of tubular product too big and make tubular product produce great internal stress after the shaping, reduce the mechanics, the physical properties of tubular product.

In summary, the present application has the following beneficial effects:

1. because this application polyethylene is as main base material, mix aramid fiber and improve the mechanical strength of gas pipe, and use high density polyethylene, oxidation graphite alkene, carbon fiber etc. to make antistatic master batch, because oxidation graphite alkene is after the reduction makes graphite alkene, have preferred electric conductivity, and graphite alkene and carbon fiber have better affinity, consequently use high density polyethylene as the compatibility of carbon fibre and graphite alkene, enable carbon fibre and graphite alkene homodisperse in the gas pipe, thereby reach preferred antistatic effect and comparatively lasting antistatic properties.

2. The graphene oxide is preferably reduced by a dopamine reduction method, because the wettability of the carbon fiber treated by the dopamine solution and the high-density polyethylene is enhanced, and the viscosity of the dopamine with hydroxyl and amino polar groups can be better on the high-density polyethylene, so that the interface bonding force of the carbon fiber and the high-density polyethylene is improved, and the joint has higher hot melt strength when the gas pipe is connected in a hot melting manner.

3. The aramid fiber is preferably pretreated by chemical silver plating, polyvinylidene fluoride and the like, so that the conductivity of the aramid fiber can be improved, the mechanical strength of the aramid fiber is increased, the tensile strength of a gas pipe is improved, and the tensile strength of a hot-melt joint is improved.

Detailed Description

Preparation examples 1 to 6 of antistatic Master batch

Preparation example 1: (1) Mixing 0.5kg of graphene oxide with 15kg of deionized water to prepare graphene oxide dispersion liquid;

(2) Dipping 2kg of carbon fiber in the graphene oxide dispersion liquid, heating to 80 ℃, dipping for 48h, vacuum drying for 4h at 60 ℃, hot pressing for 30s at 120 ℃ under the pressure of 0.4MPa, and reducing by using dopamine to obtain graphene modified carbon fiber; the dopamine reduction method comprises the following steps: dissolving 0.01mol of Tris (hydroxymethyl) aminomethane in deionized water, adjusting the pH value to 8 to prepare a Tris solution with the concentration of 10mmol/l, and preparing a dopamine solution with the concentration of 2mg/ml by using the Tris solution;

adding the hot-pressed carbon fibers into a dopamine solution, soaking for 24 hours at room temperature, washing with deionized water until filtrate is colorless and transparent, and vacuum-drying for 12 hours at 60 ℃;

(3) Drying 5kg of high-density polyethylene PE100 at 80 ℃ for 3h, mixing and dispersing the high-density polyethylene PE100 with 2kg of long-acting antistatic agent and graphene modified carbon fiber, and performing melt extrusion and granulation at 270 ℃ to obtain the antistatic master batch, wherein the long-acting antistatic agent is polyethylene wax grafted sodium acrylate.

Preparation example 2: (1) Mixing 0.3kg of graphene oxide with 10kg of deionized water to prepare graphene oxide dispersion liquid; (2) Dipping 1kg of carbon fiber in the graphene oxide dispersion liquid, heating to 90 ℃, dipping for 20h, vacuum drying for 4h at 60 ℃, hot pressing for 10s at 150 ℃ under the pressure of 0.8MPa, and reducing by using dopamine to obtain graphene modified carbon fiber; the dopamine reduction method comprises the following steps: dissolving 0.01mol of Tris (hydroxymethyl) aminomethane in deionized water, adjusting the pH value to 8.5 to prepare a Tris solution with the concentration of 10mmol/l, and preparing a dopamine solution with the concentration of 2mg/ml by using the Tris solution; adding the hot-pressed carbon fibers into a dopamine solution, soaking for 20h at room temperature, washing with deionized water until the filtrate is colorless and transparent, and vacuum-drying at 60 ℃ for 12h;

(3) Drying 4kg of high-density polyethylene PE100 at 80 ℃ for 3h, mixing and dispersing the high-density polyethylene PE100 with 1kg of long-acting antistatic agent and graphene modified carbon fibers, and performing melt extrusion and granulation at 270 ℃ to obtain the antistatic master batch, wherein the long-acting antistatic agent is polyethylene wax grafted sodium acrylate.

Preparation example 3: the difference from preparation example 1 is that hot pressing was not performed.

Preparation example 4: the difference from preparation example 1 is that reduction was not carried out.

Preparation example 5: the difference from the preparation example 1 is that the reduction method in the step (2) adopts ultraviolet ray reduction, and the specific method is as follows:

(1) Mixing 0.5kg of graphene oxide with 15kg of deionized water, and adding a reducing agent with the mass ratio of the reducing agent to the graphene oxide being 1;

(2) Soaking 2kg of carbon fiber in the graphene oxide dispersion liquid, heating to 80 ℃, soaking for 48h, vacuum drying for 4h at 60 ℃, hot-pressing for 30s at 120 ℃ under the pressure of 0.4MPa, and placing the hot-pressed carbon fiber under an ultraviolet lamp (the power is 15W, the wavelength is 254nm, and the distance from the carbon fiber is 6 cm) for irradiation reduction for 0.5h to prepare graphene modified carbon fiber;

Preparation example 6: drying 5kg of high-density polyethylene PE100 at 80 ℃ for 3h, uniformly mixing with 2kg of long-acting antistatic agent, 0.5kg of graphene oxide, 2kg of carbon fiber and 1kg of deionized water, and performing melt extrusion and granulation at 270 ℃ to obtain the antistatic master batch, wherein the long-acting antistatic agent is polyethylene wax grafted sodium acrylate.

Examples

Example 1: an antistatic PE gas pipe comprises 100kg of polyethylene, 75kg of antistatic master batch, 8kg of flame retardant, 9kg of anti-aging agent, 35kg of aramid fiber and 20kg of carbon black, wherein the polyethylene is PE100, the antistatic master batch is prepared from preparation example 1, the flame retardant is magnesium hydroxide, the anti-aging agent comprises dibutyl hydroxy toluene, butyl hydroxy anisole and tert-butyl hydroquinone in a mass ratio of 1.

The preparation method of the antistatic PE gas pipe comprises the following steps:

s1, drying the carbon black and polyethylene at 75 ℃ for 5 hours;

s2, uniformly mixing the dried polyethylene and carbon black with the antistatic master batch, the anti-aging agent, the flame retardant and the aramid fiber to obtain a mixture;

s3, preheating a machine barrel, and performing extrusion molding on the mixture to obtain a tubular gas pipe;

and S4, sequentially carrying out vacuum forming, spray cooling, marking and traction cutting on the gas pipe to obtain a finished product.

Example 2: an antistatic PE gas pipe comprises 90kg of polyethylene, 3.5kg of antistatic master batch, 4kg of flame retardant, 5kg of anti-aging agent, 30kg of aramid fiber and 15kg of carbon black, wherein the polyethylene is PE100, the antistatic master batch is prepared by preparation example 2, the flame retardant is aluminum hydroxide, the anti-aging agent comprises dibutyl hydroxy toluene, butyl hydroxy anisole and tert-butyl hydroquinone in a mass ratio of 1.

s1, drying carbon black and polyethylene at 85 ℃ for 3h;

Example 3: an antistatic PE gas pipe is different from the PE gas pipe in example 1 in that antistatic master batches are prepared in preparation example 3.

Example 4: an antistatic PE gas pipe is different from the PE gas pipe in example 1 in that antistatic master batches are prepared in preparation example 4.

Example 5: an antistatic PE gas pipe is different from the PE gas pipe in example 1 in that antistatic master batches are prepared in preparation example 5.

Example 6: an antistatic PE gas pipe is different from the PE gas pipe in example 1 in that antistatic master batches are prepared from preparation example 6.

Example 7: an antistatic PE gas pipe is different from the antistatic PE gas pipe in example 1 in that aramid fiber is pretreated by the following steps:

carrying out chemical silvering on 5kg of aramid fiber to prepare silvered aramid fiber;

adding the obtained silver-plated aramid fiber into absolute ethyl alcohol, adding thioglycollic acid, carrying out a dark reaction at room temperature for 24 hours in a nitrogen atmosphere, centrifuging, and carrying out cyclic alternate centrifugal washing on absolute ethyl alcohol and deionized water at a rotating speed of 6000rpm to obtain the carboxylated nano silver aramid fiber, wherein the mass ratio of the silver-plated aramid fiber to the absolute ethyl alcohol to the thioglycollic acid is 1;

mixing 2kg of polyvinylidene fluoride particles with 3kg of 1, 4-butanediamine solution and 0.5 g of sodium carbonate, soaking for 12 hours at room temperature, centrifuging, washing and drying to obtain aminated polyvinylidene fluoride;

dispersing the obtained carboxylated nano-silver aramid fiber in 10kg of absolute ethanol solution, adding the obtained aminated polyvinylidene fluoride, mixing, continuously reacting for 24 hours at room temperature in a nitrogen atmosphere, washing with deionized water, centrifuging, drying, and melting and granulating at 185 ℃.

Example 8: an antistatic PE gas pipe is different from that of preparation example 7 in that chemical silvering is not carried out on the surface of aramid fiber.

Example 9: the antistatic PE gas pipe is different from the preparation example 7 in that silver-plated aramid fibers are not subjected to carboxylation treatment, polyvinylidene fluoride particles are not subjected to amination treatment, and the silver-plated aramid fibers and the polyvinylidene fluoride particles are directly blended and then melted and granulated at 185 ℃.

Comparative example

Comparative example 1: an antistatic PE gas pipe is different from the PE gas pipe in example 1 in that a long-acting antistatic agent is not added.

Comparative example 2: an antistatic PE gas pipe is different from the antistatic PE gas pipe in example 1 in that graphene oxide is not added.

Preparation example 3: an antistatic PE gas pipe is different from the antistatic PE gas pipe in example 1 in that carbon fibers are not added.

Comparative example 4: an antistatic PE gas pipe is different from that in the embodiment 1 in that aramid fiber is not added.

Comparative example 5: a polyethylene gas pipe comprises 86 parts of polyethylene 100, 0.4 part of styrene, 0.4 part of acrylonitrile, 4 parts of antistatic color master batch, 0.2 part of butylated hydroxytoluene, 0.2 part of butylated hydroxyanisole, 0.2 part of tert-butylhydroquinone, 0.1 part of vitriol and 4 parts of copper, wherein the copper can be a fine copper wire, 1 part of lithium ion, 1 part of aluminum hydroxide, 0.1 part of octabromoether, 0.1 part of triphenyl phosphate, 0.1 part of hexabromocyclododecane, 0.2 part of decabromodiphenylethane, 1.3 parts of polystyrene, 0.3 part of trichloro phosphate, 0.1 part of 2.3-chloropropyl, 0.1 part of N-methylguanidine, 0.1 part of ammonium polyphosphate and 0.1 part of decabromodiphenylether. The manufacturing method of the polyethylene gas pipe comprises the following steps: step 101 is: heating and stirring polyethylene to 38 ℃;

step 102 is: adding an antistatic agent, an anti-aging agent and a catalyst into polyethylene heated to 38 ℃ and uniformly stirring to obtain a mixed raw material;

step 103 is: preheating the extruder to ensure that the temperature of the extruder is 200 ℃;

step 104 is: putting the mixed raw materials into an extruder to obtain a tubular polyethylene gas pipe;

step 105 is: carrying out vacuum shaping on the polyethylene gas pipe;

step 106 is: and cooling the polyethylene gas pipe subjected to vacuum forming.

Performance test

Gas pipes were prepared according to the methods in examples and comparative examples, and the properties of the gas pipes were examined with reference to the following methods, and the examination results are reported in table 1.

1. Surface resistivity: detecting initial surface resistivity according to GB/T1410-2006 test method for volume resistivity and surface resistivity of solid insulating materials, scrubbing for 30 times by water, and detecting the surface resistivity again;

2. tensile strength: detecting according to GB/T8804.3-2003 part 3 determination of tensile property of polyolefin pipes for thermoplastic plastics;

3. elongation at break: detecting according to GB/T8804.1-2203 general rule of test methods for determining the tensile property of thermoplastic plastic pipes 1;

4. weld bond tensile strength: according to GB/T19810-2005 test methods for tensile strength and tensile failure modes of polyethylene pipe and key hot melt butt joints.

TABLE 1 gas pipe Performance test results

The antistatic master batches prepared in preparation examples 1 and 2 are adopted in example 1 and example 2 respectively, and the data in Table 1 show that the surface resistivity of the gas pipe prepared in example 1 and example 2 is lower than 5X 10 ⁶ Omega, has better antistatic effect and still has less than 6 multiplied by 10 after 30 times of scrubbing ⁸ Omega surface resistivity, and lasting antistatic effect.

Example 3 is different from example 1 in that the antistatic master batch prepared in preparation example 3 is used, and since hot pressing is not performed in preparation example 3, the data in table 1 show that the gas pipe prepared in example 3 has increased surface resistivity, and the increase after scrubbing is more obvious, and the antistatic effect is reduced, which indicates that the hot pressing can increase the antistatic effect and the antistatic durability of the gas pipe.

Example 4 compared to example 1, the antistatic master batch prepared in preparation example 4 was used, and since no reduction was performed, the gas pipe prepared in example 4 had a higher surface resistivity than example 1, and the surface resistivity after scrubbing was increased, indicating that reduction can improve the antistatic effect of the gas pipe.

In example 5, the antistatic master batch prepared in preparation example 5 was used, and in preparation example 5, graphene oxide was reduced by an ultraviolet radiation reduction method, and compared with example 1, the initial surface resistivity was similar, but after 30 times of scrubbing, the surface resistivity of the gas pipe was increased, which indicates that although a gas pipe having a higher initial antistatic effect could be obtained by an ultraviolet reduction method, the antistatic durability of the gas pipe was inferior to that of example 1.

In example 6, the antistatic master batch prepared in preparation example 6 was used, and in preparation example 6, the antistatic master batch prepared by mixing and extruding graphene oxide, carbon fiber and the like was higher in surface resistivity and lower in antistatic effect than in example 1 in example 6.

In example 7, compared to example 1, aramid fibers were also pretreated with polyvinylidene fluoride or the like, and table 1 shows that the gas pipe prepared in example 7 has increased tensile strength and elongation at break, decreased surface resistivity, enhanced antistatic effect, increased weld bead tensile strength, and tight and firm weld.

In example 8, compared with example 7, the surface of the aramid fiber was not chemically plated with silver, and table 1 shows that the gas pipe made in example 8 has a surface resistivity similar to that of example 1, the antistatic effect is reduced compared with example 7, and the weld tensile strength of the gas pipe is reduced.

Compared with the embodiment 7, the embodiment 9 has the advantages that the silver-plated aramid fiber and the polyvinylidene fluoride particles are blended, the interface bonding force between the silver-plated aramid fiber and the polyvinylidene fluoride is reduced, the mechanical strength of the gas pipe is reduced, and the tensile strength of a welded junction is reduced.

Compared with the example 1, the long-acting antistatic agent, the graphene oxide and the carbon fiber are not added in the comparative examples 1 to 3 respectively, the antistatic effect of the gas pipe prepared in the comparative examples 1 to 3 is reduced, the aramid fiber is not added in the comparative example 4, the mechanical property of the gas pipe prepared in the comparative examples 3 and 4 is weakened, and the tensile strength of a welded junction is reduced.

Comparative example 5 is a gas pipe prepared in the prior art, the initial antistatic effect is inferior to that of example, after 30 times of scrubbing, the antistatic effect is reduced, the antistatic durability is poor, the tensile strength of a welded joint is lower than that of example 1, the strength of a hot-melt joint is not high, and the gas pipe is easy to break.

The present embodiment is only for explaining the present application, and it is not limited to the present application, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present application.

Claims

1. The antistatic PE gas pipe is characterized by comprising the following components in parts by weight: 90-100 parts of polyethylene, 3.5-7 parts of antistatic master batch, 4-8 parts of flame retardant, 5-9 parts of anti-aging agent, 30-35 parts of aramid fiber and 15-20 parts of carbon black;

the antistatic master batch comprises the following components in parts by weight: 4-5 parts of high-density polyethylene, 0.3-0.5 part of graphene oxide, 1-2 parts of carbon fiber, 10-15 parts of deionized water and 1-2 parts of long-acting antistatic agent;

the antistatic master batch is prepared by the following method:

drying high-density polyethylene, mixing with a long-acting antistatic agent and the graphene modified carbon fiber, dispersing, melting and granulating to prepare antistatic master batches;

the aramid fiber is pretreated by the following steps:

adding the silver-plated aramid fiber into an absolute ethanol solution, adding thioglycollic acid, carrying out room-temperature dark reaction for 20-24h in a nitrogen atmosphere, centrifuging, and washing to obtain the carboxylated nano silver aramid fiber;

mixing polyvinylidene fluoride particles with a 1, 4-butanediamine solution and sodium carbonate, soaking at room temperature for 12-16h, centrifuging, washing and drying to obtain aminated polyvinylidene fluoride;

2. The antistatic PE gas pipe as claimed in claim 1, wherein the hot pressing temperature is 120-150 ℃ and the pressure is 0.4-0.8MPa.

3. The antistatic PE gas pipe according to claim 1, wherein the reduction method is selected from one of ultraviolet reduction and dopamine reduction.

4. The antistatic PE gas pipe as claimed in claim 3, wherein the specific method for reducing dopamine is as follows: dissolving Tris (hydroxymethyl) aminomethane with deionized water, adjusting pH to 8-8.5 to prepare a Tris solution, and preparing a dopamine solution by using the Tris solution;

5. The antistatic PE gas pipe according to claim 3, wherein the ultraviolet light reduction method is to add a reducing agent into the graphene oxide dispersion liquid, the reducing agent is hydrazine hydrate with the mass concentration of 1-1.5%, and the mass ratio of the reducing agent to the graphene oxide is 1-2.

6. The antistatic PE gas pipe according to claim 1, wherein the long-acting antistatic agent is polyethylene wax grafted sodium acrylate.

7. The antistatic PE gas pipe according to claim 1, wherein the flame retardant is selected from one of magnesium hydroxide, aluminum hydroxide and organic bromide;

8. The method for preparing an antistatic PE gas pipe as claimed in any one of claims 1 to 7, comprising the steps of:

drying the carbon black and polyethylene at 75-85 ℃ for 3-5h;