Polyethylene winding solid-wall top-pull pipe with sealing self-locking connector and preparation method of polyethylene winding solid-wall top-pull pipe

Abstract

The invention provides a sealed self-locking interface polyethylene winding solid-wall top-pull pipe and a preparation method of the sealed self-locking interface polyethylene winding solid-wall top-pull pipe. The preparation method comprises the following steps: weighing and mixing an antioxidant, a plasticizer, a release agent, a first inorganic filler and first polyethylene resin, feeding into a first screw extruder, heating, melting and extruding, and cooling and molding to obtain a strip; an antioxidant, a plasticizer, a slipping agent, phenolic resin, a second inorganic filler and second polyethylene resin are weighed and mixed, the mixture is fed into a second screw extruder to be heated, melted and extruded, and a lining pipe is obtained after cooling forming; the strip is firstly fed into a glue dipping pool containing epoxy resin for glue dipping and then fed into a winding machine, so that the strip is heated, softened and wound to the outer periphery of the lining pipe, and the solid-wall top pull pipe is obtained; wherein the first inorganic filler comprises silicon dioxide and magnesium borate whiskers, and the second inorganic filler comprises silane modified talcum powder. The solid-wall top-pull pipe provided by the invention has excellent heat resistance.

Description

Technical Field

[0001] The invention relates to the technical field of polymer materials, and in particular to a sealed self-locking interface polyethylene winding solid wall top-drawn tube and a preparation method thereof. Background Art

[0002] Solid wall pipe refers to a pipe with the same ring shape in any cross section and solid wall. Solid wall pipe has the characteristics of thick wall, high hardness and precise size. Solid wall pipe also needs to have strong durability and corrosion resistance, and can adapt to use in various environmental conditions.

[0003] Among them, solid wall pipes are particularly widely used in the construction field, including indoor drainage systems, outdoor piping systems, water supply systems, ventilation systems, etc. In the agricultural field, solid wall pipes can be used to build high-strength and high-durability water / heating pipe systems, as well as agricultural water-saving irrigation systems. These applications meet the agricultural needs for water conservation, enhanced irrigation, and increased production. In the industrial field, solid wall pipes are often used in the chemical industry, pharmaceutical industry, food processing and other industries as pipes for transporting liquids or gases. In addition, solid wall pipes can also be used in other industries such as electricity, gas and water treatment.

[0004] Solid wall pipes for different application scenarios need to have different performance or characteristics. For example, solid wall pipes used in the construction field need to have excellent durability and corrosion resistance, so that the solid wall pipes can guarantee a long service life in various weather environments. Solid wall pipes used in the industrial field need to be non-toxic, odorless, and have high strength. In summary, how to improve mechanical strength and mechanical properties, as well as durability and corrosion resistance, are the two core technical issues in the field of solid wall pipes.

[0005] Among the various application scenarios of solid wall pipes, top-pull pipes are a very important and common one. Top-pull pipes are an auxiliary tool in pipeline construction. They are mainly used to gradually advance the pipe in the soil by applying a pulling force at one end of the pipe and a pushing force at the other end. Among them, the interface of the sealed self-locking interface top-pull pipe is designed with a self-locking structure. When the pipe fitting is centered and pushed forward, the front end of the pipe fitting will resist the front end structure of the joint and through internal springs and other structures, the claws at the front end of the joint will open and automatically lock the pipe fitting, while forming a good sealing surface to ensure the sealing of the pipeline system. Sealed self-locking interface top-pull pipes are widely used in drainage, sewage, water supply, gas and other fields, especially in projects such as urban pipeline network reconstruction and old pipeline repair. It has significant advantages.

[0006] Since the processing of sealed self-locking interface solid wall top-drawn tubes is more complicated than that of ordinary solid wall top-drawn tubes, it is very necessary for the polymer materials used to manufacture sealed self-locking interface solid wall top-drawn tube products to have good machinability and processing accuracy in addition to meeting the basic requirements of mechanical strength, mechanical properties, corrosion resistance, durability, etc.

[0007] Polyethylene (PE) winding pipe is a thermoplastic plastic pipe made of polyethylene resin as the main material and using a winding molding process. Polyethylene materials are widely used in many fields due to their unique physical, chemical, thermal and mechanical properties. In particular, polyethylene has good chemical stability, can withstand the erosion of most acids and alkalis, has good impact resistance, good wear resistance, and polyethylene has excellent low-temperature resistance, which enables it to maintain good mechanical properties in cold environments. Therefore, polyethylene materials are very suitable for solid wall top-drawn pipes, especially for application scenarios of solid wall top-drawn pipes for water supply and drainage systems that require low-temperature resistance. In addition, polyethylene has good fluidity, low processing temperature, moderate viscosity, mature technology, and is easy to process with high processing precision. Therefore, polyethylene-wound solid wall top-drawn pipes have become increasingly popular in the market in recent years.

[0008] The polyethylene material in the prior art has the disadvantages of not being heat resistant when used in solid wall top-drawn pipe products, and not being durable and having a service life that is not ideal in certain high temperature scenarios (such as hot summer weather or when the liquid medium is higher than room temperature). Summary of the invention

[0009] One of the problems solved by the present invention is how to provide a polyethylene-wound solid-wall top-drawn tube with a sealed self-locking interface and excellent heat resistance.

[0010] In order to solve at least one of the above problems, the present invention provides a method for preparing a sealed self-locking interface polyethylene wound solid wall top-drawn tube, the preparation method comprising:

[0011] S100, weighing and mixing an antioxidant, a plasticizer, a release agent, a first inorganic filler and a first polyethylene resin, sending them into a first screw extruder, heating and melting them, and extruding them, and cooling and molding them to obtain a strip;

[0012] S200, weighing and mixing an antioxidant, a plasticizer, a lubricant, a phenolic resin, a second inorganic filler, and a second polyethylene resin, and feeding the mixture into a second screw extruder to heat, melt, and extrude the mixture, and cooling and molding the mixture to obtain an inner liner pipe;

[0013] S300, firstly sending the strip into a dipping tank containing epoxy resin for dipping, and then sending the strip into a winding machine to heat and soften the strip and wind it to the outer periphery of the inner liner pipe to obtain a solid wall top-drawn pipe;

[0014] The first inorganic filler includes silicon dioxide and magnesium borate whisker, and the second inorganic filler includes modified talc treated with silane.

[0015] In any of the above technical solutions, in S100, the mass ratio of antioxidant: plasticizer: release agent: first inorganic filler: first polyethylene resin is (1-2): (1-3): (2-4): (10-30): 100.

[0016] In any of the above technical solutions, in S200, the mass ratio of antioxidant: plasticizer: lubricant: phenolic resin: second inorganic filler: second polyethylene resin is (1-2): (1-3): (2-4): (6-12): (10-30): 100.

[0017] In any of the above technical solutions, in S100, the first polyethylene resin includes low-density polyethylene and high-density polyethylene in a mass ratio of (1-2):(8-9), and the heating range of the first screw extruder is 180°C to 220°C.

[0018] In any of the above technical solutions, in S200, the second polyethylene resin includes low-density polyethylene and high-density polyethylene in a mass ratio of (3-4):(6-7), and the heating range of the second screw extruder is 160°C to 200°C.

[0019] In any of the above technical solutions, in S100 and / or S200, the antioxidant is antioxidant 1010, the plasticizer is di(2-ethylhexyl) phthalate, the release agent is pentaerythritol stearate or magnesium stearate, and the lubricant is ethylene bisstearamide.

[0020] In any of the above technical solutions, the modified talc is prepared by the following steps:

[0021] S410, tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane are mixed evenly in a closed reaction kettle, alkali solution is added dropwise to adjust the pH to 10 to 11, heated in a water bath to 90° C. to 95° C., stirred for 2 h to 4 h, and then cooled to 50° C. to 60° C.;

[0022] S420, continue to add trifluoroethyl methacrylate and ethanol 5 to 6 times the mass of trifluoroethyl methacrylate to the reactor, maintain the reaction system temperature at 50° C. to 60° C., continue stirring for 2 to 4 hours, stop keeping warm, transfer the reactants to a rotary evaporator, evaporate the solvent, and obtain a silane treatment agent;

[0023] S430, uniformly mix the silane treatment agent, talc, ethanol and water, heat to 60° C. to 65° C., stir for 1 h to 2 h, filter the solid, wash, and dry to obtain modified talc.

[0024] In any of the above technical solutions, in S410, by mass, tetramethyltetravinylcyclotetrasiloxane:octamethylcyclotetrasiloxane=(15-20):100; in S420, by mole, the amount of trifluoroethyl methacrylate added is equal to the total molar amount of tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane; in S430, by mass, silane treating agent: talcum powder: ethanol: water=(6-8):(15-25):(25-30):100.

[0025] In any of the above technical solutions, the alkali solution is a 6wt% to 12wt% sodium hydroxide aqueous solution.

[0026] The present invention also provides a sealed self-locking interface polyethylene wound solid wall top-drawn tube, and the sealed self-locking interface polyethylene wound solid wall top-drawn tube is obtained by using the preparation method of any of the above technical solutions.

[0027] Beneficial Effects

[0028] The present invention provides a method for preparing a sealed self-locking interface polyethylene-wound solid-wall top-drawn tube. The preparation method first weighs and mixes an antioxidant, a plasticizer, a release agent, a first inorganic filler and a first polyethylene resin, sends them into a first screw extruder to heat, melt and extrude, and obtains a strip after cooling and molding. Then, the antioxidant, plasticizer, lubricant, phenolic resin, a second inorganic filler and a second polyethylene resin are weighed and mixed, sent into a second screw extruder to heat, melt and extrude, and obtain an inner liner after cooling and molding. Finally, the strip is first sent to a dipping tank containing epoxy resin for dipping, and then sent to a winding machine to heat and soften the strip and wrap it around the outer periphery of the inner liner to obtain a solid-wall top-drawn tube. Among them, the present invention wraps the strip around the outer periphery of the inner liner as a reinforcing layer. Since the first inorganic filler includes silica and magnesium borate whiskers, the reinforcing layer has good mechanical strength, especially anti-deformation ability. Specifically, the addition of silica can improve the mechanical strength of the polyethylene resin. Magnesium borate whiskers have good thermal stability. In high-temperature application scenarios, magnesium borate whiskers will not experience strength loss, and can give solid-wall top-pull tubes better high-temperature resistance. And magnesium borate whiskers have good fracture strength and elastic modulus, making solid-wall top-pull tubes less likely to deform. In addition, the inner liner of the present invention has a long service life. Specifically, the second inorganic filler includes silane-treated modified talcum powder, which can not only improve the stiffness, impact strength, and creep resistance of the inner liner, but also improve the hardness, surface scratch resistance, and wear and corrosion resistance of the inner liner. Silane treatment can improve the dispersion properties of talcum powder, ensuring that it is evenly and stably dispersed in the polyethylene resin. DETAILED DESCRIPTION

[0029] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the following is a detailed description of the specific embodiments of the present invention.

[0030] Unless otherwise specified, the reagents and raw materials used in the present invention can be purchased through commercial channels. The experimental methods in the following examples without specifying specific conditions are selected according to conventional methods and conditions, or according to the product specifications.

[0031] The embodiment of the present invention provides a method for preparing a polyethylene-wound solid-wall top-drawn tube with a sealed self-locking interface. The preparation method adopted by the present invention comprises:

[0032] S100, weighing and mixing an antioxidant, a plasticizer, a release agent, a first inorganic filler and a first polyethylene resin, sending them into a first screw extruder, heating and melting them, and extruding them, and cooling and molding them to obtain a strip;

[0033] S200, weighing and mixing an antioxidant, a plasticizer, a lubricant, a phenolic resin, a second inorganic filler, and a second polyethylene resin, and feeding the mixture into a second screw extruder to heat, melt, and extrude the mixture, and cooling and molding the mixture to obtain an inner liner pipe;

[0034] S300, the strip is first sent into a dipping tank containing epoxy resin for dipping, and then sent into a winding machine to heat and soften the strip and wind it to the outer periphery of the liner pipe to obtain a solid wall top-drawn pipe.

[0035] The present invention prepares a solid wall top-drawn pipe by winding a strip around the outer periphery of an inner liner pipe as a reinforcement layer, wherein both the strip and the inner liner pipe use polyethylene resin as the main material and add necessary auxiliary additives.

[0036] It should be noted that the equipment and process conditions used for heating, melting and extruding polyethylene resin and related auxiliary materials, as well as cooling and molding are relatively mature existing technologies. Those skilled in the art are capable of selecting and adjusting them, and the present invention will not elaborate on them.

[0037] It should also be noted that those skilled in the art can select the type and molecular weight of polyethylene resin according to actual needs. For example, high-density polyethylene (HDPE) and low-density polyethylene (LDPE) are selected and used in a certain proportion. Among them, high-density polyethylene has a higher crystallinity (80% to 90%), and its hardness, tensile strength and creep are better than low-density polyethylene, and its melting temperature is relatively high. Low-density polyethylene has good elongation and processability, and its melting temperature is relatively low.

[0038] Preferably, in S100, the first polyethylene resin comprises low-density polyethylene and high-density polyethylene in a mass ratio of (1-2): (8-9), and the heating interval of the first screw extruder is 180° C. to 220° C. In S200, the second polyethylene resin comprises low-density polyethylene and high-density polyethylene in a mass ratio of (3-4): (6-7), and the heating interval of the second screw extruder is 160° C. to 200° C.

[0039] The selection of the raw material for dipping is common knowledge to those skilled in the art. The advantage of using epoxy resin is that it can improve the wear resistance and corrosion resistance of the strip. The epoxy resin in the dipping tank needs to be heated to a liquid resin before use.

[0040] It is understandable that after obtaining the solid wall top-drawn tube product, it can be cut and coated with a protective coating according to actual needs.

[0041] In some embodiments of the present invention, in S100, the mass ratio of antioxidant:plasticizer:release agent:first inorganic filler:first polyethylene resin is (1-2):(1-3):(2-4):(10-30):100.

[0042] Preferably, in S100 , the weight ratio of antioxidant:plasticizer:release agent:first inorganic filler:first polyethylene resin is 1:2:2:20:100.

[0043] In some embodiments of the present invention, in S200, the mass ratio of antioxidant: plasticizer: lubricant: phenolic resin: second inorganic filler: second polyethylene resin is (1-2): (1-3): (2-4): (6-12): (10-30): 100.

[0044] Preferably, in S200, the weight ratio of antioxidant:plasticizer:lubricant:phenolic resin:second inorganic filler:second polyethylene resin is 1:2:2:6:25:100.

[0045] Among them, antioxidants and plasticizers are added to the strips and the inner liner. Polyethylene resin materials are easily affected by environmental factors such as oxygen, heat and light during long-term use or storage, and oxidation reactions occur, resulting in performance degradation. The role of antioxidants is to effectively delay or inhibit the progress of this oxidation process, thereby maintaining the performance stability of polyethylene resin materials. The present invention can use phenolic antioxidants such as butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), tert-butylhydroquinone (TBHQ), and aromatic amine antioxidants such as compounds such as diphenylamine, p-phenylenediamine and dihydroquinoline and their derivatives or polymers, and can also use hindered phenolic antioxidants such as 2,6-tertiary butyl-4-methylphenol and bis (3,5-tertiary butyl-4-hydroxyphenyl) sulfide. Plasticizers can increase the softness and plasticity of polyethylene resins, making them easier to process. By reducing the force between resin molecular chains, plasticizers can make polyethylene resin materials easier to shape at lower temperatures, thereby meeting processing requirements. The present invention can use phthalate plasticizers such as dioctyl phthalate (DOP), dibutyl phthalate (DBP), etc., can also use aliphatic dibasic acid ester plasticizers such as dioctyl adipate (DOA), dioctyl sebacate (DOS), etc., can also use phosphate plasticizers such as tricresyl phosphate (TCP), toluene diphenyl phosphate (CDP), etc. Preferably, in S100 and S200, the antioxidant is antioxidant 1010, and the plasticizer is di(2-ethylhexyl) phthalate.

[0046] The present invention adds a release agent to the raw material components of the strip, and adds a lubricant to the raw material components of the liner. The addition of the release agent can enable the strip to maintain integrity and good appearance quality during the molding process, and reduce the occurrence of defects such as cracks. By adding a lubricant, the polyethylene resin material can flow more smoothly during the extrusion process, reducing friction with the equipment. In S100, the release agent is preferably pentaerythritol stearate or magnesium stearate, and in S200, the lubricant is preferably ethylene bisstearamide.

[0047] The present invention adds phenolic resin to the raw material components of the inner liner pipe, and the phenolic resin contains a large number of benzene rings and is cross-linked into a three-dimensional structure, so it has good heat resistance. The addition of phenolic resin helps the solid wall top-drawn pipe to maintain stable performance under high temperature conditions.

[0048] The present invention adds a first inorganic filler to the raw material components of the strip, and the first inorganic filler includes silicon dioxide and magnesium borate whiskers. Silicon dioxide can improve the mechanical strength of polyethylene resin. Magnesium borate whiskers have good thermal stability. In high-temperature application scenarios, magnesium borate whiskers will not lose strength, and can give the solid wall top-drawn tube better high-temperature resistance. In addition, magnesium borate whiskers have good fracture strength and elastic modulus, making the solid wall top-drawn tube not easy to deform.

[0049] The invention adds a second inorganic filler to the raw material components of the inner liner, and the second inorganic filler includes modified talc treated with silane. The talc can not only improve the stiffness, impact strength, creep resistance, but also improve the hardness, surface scratch resistance, wear resistance and corrosion resistance of the inner liner. Silane treatment can improve the dispersibility of talc and ensure that it is evenly and stably dispersed in the polyethylene resin.

[0050] Preferably, the modified talc is prepared by the following steps:

[0051] S410, tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane are mixed evenly in a closed reaction kettle, alkali solution is added dropwise to adjust the pH to 10 to 11, heated in a water bath to 90° C. to 95° C., stirred for 2 h to 4 h, and then cooled to 50° C. to 60° C.;

[0052] S420, continue to add trifluoroethyl methacrylate and ethanol 5 to 6 times the mass of trifluoroethyl methacrylate to the reactor, maintain the reaction system temperature at 50° C. to 60° C., continue stirring for 2 to 4 hours, stop keeping warm, transfer the reactants to a rotary evaporator, evaporate the solvent, and obtain a silane treatment agent;

[0053] S430, uniformly mix the silane treatment agent, talc, ethanol and water, heat to 60° C. to 65° C., stir for 1 h to 2 h, filter the solid, wash, and dry to obtain modified talc.

[0054] In some embodiments of the present invention, in S410, the ratio of tetramethyltetravinylcyclotetrasiloxane to octamethylcyclotetrasiloxane is (15-20):100 by mass.

[0055] Preferably, in S410, by mass, tetramethyltetravinylcyclotetrasiloxane:octamethylcyclotetrasiloxane=18:100;

[0056] In some embodiments of the present invention, in S420, the amount of trifluoroethyl methacrylate added is equal to the total molar amount of tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane, based on moles.

[0057] In some embodiments of the present invention, in S430, the ratio of silane treating agent: talc: ethanol: water is (6-8): (15-25): (25-30): 100 by mass.

[0058] Preferably, in S430, by mass, the ratio of silane treatment agent: talcum powder: ethanol: water = 8:18:25:100.

[0059] In some embodiments of the present invention, the alkali solution is a 6 wt % to 12 wt % sodium hydroxide aqueous solution.

[0060] The reason why the present invention adopts the above steps is that, by adding alkaline water bath reaction of tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane in a closed reactor, tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane can be ring-opened polymerized to form linear tetrasiloxane. Linear tetrasiloxane reacts with trifluoroethyl methacrylate that can undergo amine-ene addition to generate fluorinated silane as a silane treatment agent. Since the surface tension of the fluorinated functional group in the fluorinated silane is lower than that of the common hydrocarbon functional group, the talcum powder processed by the present invention is closer to the surface energy of the resin, and the hydrophobicity and oil-proof and antifouling properties are better. In addition, the fluorinated silane can be entangled with the polyethylene segment during the melt extrusion process and form a physical crosslink, promote the interface bonding of talcum powder and polyethylene, and ensure that talcum powder is more evenly dispersed in polyethylene. Accordingly, the inner liner pipe with the talcum powder obtained by the above steps is added, which is more suitable for the construction of indoor drainage and sewage pipelines, and its performance is more uniform and stable.

[0061] Example 1

[0062] In this embodiment, a series of pipe samples for manufacturing sealed self-locking interface polyethylene winding solid wall top-drawn pipes are prepared. The raw material ratios used are shown in Table 1. The preparation steps are as follows:

[0063] S1. According to the mass ratio in Table 1, tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane were mixed uniformly in a closed reaction vessel, 8 wt % sodium hydroxide aqueous solution was added dropwise to adjust the pH to 10 to 11, heated in a water bath to 90° C., stirred for 2 h, and then cooled to 50° C.;

[0064] S2, continue to add trifluoroethyl methacrylate and ethanol 5 times the mass of trifluoroethyl methacrylate to the reactor, wherein, in terms of moles, the amount of trifluoroethyl methacrylate added is equal to the total molar amount of tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane, maintain the reaction system temperature of 55°C, continue stirring for 2h, stop keeping warm, transfer the reactants to a rotary evaporator, evaporate the solvent, and obtain a silane treatment agent;

[0065] S3. According to the mass ratio in Table 1, the silane treatment agent, talc, ethanol and water were mixed evenly, heated to 60°C, stirred for 2h, the solid was filtered, washed with water twice, and infrared dried to obtain modified talc;

[0066] S4. According to the mass ratio in Table 1, antioxidant 1010, di(2-ethylhexyl) phthalate, pentaerythritol stearate, silicon dioxide, magnesium borate whisker and the first polyethylene resin are weighed and mixed, and sent into a first screw extruder to heat and melt at 180° C. to 220° C. and extrude, and then cooled and formed to obtain a strip; wherein the first polyethylene resin comprises low-density polyethylene and high-density polyethylene in a mass ratio of 1:9;

[0067] S5. According to the mass ratio in Table 1, antioxidant 1010, di(2-ethylhexyl) phthalate, ethylene bisstearamide, phenolic resin, modified talc and the second polyethylene resin are weighed and mixed, and sent into the second screw extruder to heat and melt at 160°C to 200°C and extrude, and after cooling and molding, an inner liner is obtained; the second polyethylene resin includes low-density polyethylene and high-density polyethylene in a mass ratio of 3:7.

[0068] Polyethylene;

[0069] S6. The strip is first sent into a dipping tank containing epoxy resin for dipping, and then sent into a winding machine to heat and soften the strip and wind it to the outer periphery of the liner pipe to obtain a solid wall top-drawn pipe.

[0070] Table 1

[0071]

[0072] 5 Performance Testing

[0073] GB / T 14152-2001 and GB / T 8804.3 were used to test the impact properties and tensile strength of samples 1 to 4 before and after accelerated aging. The test results are shown in Table 2. The accelerated aging conditions are:

[0074] Treat in 90℃ oven for 200h.

[0075] Table 2

[0076] performance Sample 1 Sample 2 Sample 3 Sample 4 Impact properties (TIR, %)-before accelerated aging 9.2 8.9 9.1 8.4 Tensile strength (MPa) - before accelerated aging 16.8 16.2 15.8 17.9 Impact properties (TIR, %) - after accelerated aging 9.8 9.5 9.6 8.9 Tensile strength (MPa) - after accelerated aging 15.6 15.2 15.1 16.8

[0077] 10 Although the present invention is disclosed as above, the present invention is not limited thereto. Any person skilled in the art,

[0078] Various changes and modifications may be made without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be based on the scope defined by the claims.

Claims

1. A method for preparing a sealed self-locking interface polyethylene-wound solid-wall top-drawn tube, characterized in that: The preparation method comprises: S100, weighing and mixing an antioxidant, a plasticizer, a release agent, a first inorganic filler and a first polyethylene resin, sending them into a first screw extruder, heating and melting them, and extruding them, and cooling and molding them to obtain a strip; S200, weighing and mixing an antioxidant, a plasticizer, a lubricant, a phenolic resin, a second inorganic filler, and a second polyethylene resin, and feeding the mixture into a second screw extruder to heat, melt, and extrude the mixture, and cooling and molding the mixture to obtain an inner liner pipe; S300, firstly sending the strip into a dipping tank containing epoxy resin for dipping, and then sending the strip into a winding machine, so as to heat and soften the strip and wind it around the outer periphery of the inner liner pipe to obtain the solid wall top-drawn pipe; Wherein, the first inorganic filler comprises silicon dioxide and magnesium borate whisker, and the second inorganic filler comprises modified talc treated with silane.

2. The preparation method according to claim 1, characterized in that: In S100, the mass ratio of antioxidant:plasticizer:release agent:first inorganic filler:first polyethylene resin is (1-2):(1-3):(2-4):(10-30):

100.

3. The preparation method according to claim 1, characterized in that: In S200, the weight ratio of antioxidant:plasticizer:lubricant:phenolic resin:second inorganic filler:second polyethylene resin is (1-2):(1-3):(2-4):(6-12):(10-30):

100.

4. The preparation method according to claim 1, characterized in that: In S100, the first polyethylene resin includes low-density polyethylene and high-density polyethylene in a mass ratio of (1-2):(8-9), and the heating range of the first screw extruder is 180°C to 220°C.

5. The preparation method according to claim 1, characterized in that: In S200, the second polyethylene resin includes low-density polyethylene and high-density polyethylene in a mass ratio of (3-4):(6-7), and the heating range of the second screw extruder is 160°C to 200°C.

6. The preparation method according to claim 1, characterized in that: In S100 and / or S200, the antioxidant is antioxidant 1010, the plasticizer is di(2-ethylhexyl) phthalate, the release agent is pentaerythritol stearate or magnesium stearate, and the lubricant is ethylene bisstearamide.

7. The preparation method according to any one of claims 1 to 6, characterized in that The modified talcum powder is prepared by the following steps: S410, tetramethyltetravinylcyclotetrasiloxane and octamethylcyclotetrasiloxane are mixed evenly in a closed reaction kettle, alkali solution is added dropwise to adjust the pH to 10 to 11, heated in a water bath to 90° C. to 95° C., stirred for 2 h to 4 h, and then cooled to 50° C. to 60° C.; S420, continue to add trifluoroethyl methacrylate and ethanol 5 to 6 times the mass of the trifluoroethyl methacrylate to the reactor, maintain the reaction system temperature at 50° C. to 60° C., continue stirring for 2 to 4 hours, stop keeping warm, transfer the reactants to a rotary evaporator, evaporate the solvent, and obtain a silane treatment agent; S430, uniformly mix the silane treatment agent, talcum powder, ethanol and water, heat to 60° C. to 65° C., stir for 1 h to 2 h, filter the solid, wash, and dry to obtain the modified talcum powder.

8. The preparation method according to claim 7, characterized in that: In S410, by mass, tetramethyltetravinylcyclotetrasiloxane:octamethylcyclotetrasiloxane=(15-20):100; In S420, the amount of trifluoroethyl methacrylate added is equal to the total molar amount of the tetramethyltetravinylcyclotetrasiloxane and the methylcyclotetrasiloxane, in terms of moles; In S430, the ratio of silane treatment agent: talc: ethanol: water is (6-8): (15-25): (25-30): 100 by mass.

9. The preparation method according to claim 7, characterized in that: The alkali solution is a 6wt% to 12wt% sodium hydroxide aqueous solution.

10. A sealed self-locking interface polyethylene winding solid wall top pull tube, characterized in that: The sealed self-locking interface polyethylene-wrapped solid-wall top-drawn tube is obtained by the preparation method described in any one of claims 1 to 9.

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