A highly corrosion-resistant HDPE double-wall corrugated pipe and its preparation method

Abstract

The present invention provides a highly corrosion-resistant HDPE double-wall corrugated pipe, which comprises 50-80 parts of high-density polyethylene resin, 0.7-2.5 parts of titanate coupling agent, 3-4.2 parts of polyimide, 1-3 parts of paraffin, 2-5 parts of glass flakes, 1.2-2.3 parts of talcum powder, 4-5 parts of antimony trioxide, 4-10 parts of corrosion-resistant material, 2.5-3.5 parts of composite fiber, 10-26 parts of thermoreversible crosslinking agent, and 1-3 parts of crosslinking accelerator. By adding the corrosion-resistant material, the corrosion resistance of the high-density polyethylene resin is enhanced. The scientific proportioning of each raw material enables them to synergistically exert their acid and alkali resistance. At the same time, through process improvement, the chemical resistance, heat resistance and mechanical properties of polyethylene are improved, thereby enhancing the corrosion resistance of the water pipe.

Description

Technical Field

[0001] The present invention relates to the technical field of pipe processing, and particularly relates to a highly corrosion-resistant HDPE double-wall corrugated pipe and a preparation method thereof. Background Art

[0002] HDPE double-wall corrugated pipe is a new type of lightweight pipe made of high-density polyethylene, with the characteristics of light weight, high pressure resistance, good toughness, fast construction, long service life, etc. Due to its excellent pipe wall structure design, compared with pipes of other structures, the cost is greatly reduced. And because of the convenient and reliable connection, it is widely used at home and abroad. However, traditional HDPE double-wall corrugated pipes are made by combining low-pressure polyethylene and filling materials, resulting in poor corrosion resistance inside the pipe wall. At present, the main way to solve this problem is to improve it through paint coatings. However, the paint only adheres to the surface layer of the pipe. When used in high-temperature, humid or harsh environments, the outer coating is easy to fall off and is also easily corroded, greatly reducing the service life of the pipe and causing waste of resources in the pipe field. Summary of the Invention

[0003] In view of this, the present invention proposes a highly corrosion-resistant HDPE double-wall corrugated pipe and a preparation method thereof to solve the above problems.

[0004] The technical solution of the present invention is realized as follows: A highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 50 - 80 parts of high-density polyethylene resin, 0.7 - 2.5 parts of titanate coupling agent, 3 - 4.2 parts of polyimide, 1 - 3 parts of paraffin, 2 - 5 parts of glass flakes, 1.2 - 2.3 parts of talcum powder, 4 - 5 parts of antimony trioxide, 4 - 10 parts of corrosion-resistant material, 2.5 - 3.5 parts of composite fiber, 10 - 26 parts of thermoreversible crosslinking agent, 1 - 3 parts of crosslinking promoter; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 3 - 5:1 - 4:2 - 4; the corrosion-resistant material includes 2 - 6 parts of metallocene resin, 20 - 35 parts of waterborne polyurethane resin, and 1 - 5 parts of modified graphene.

[0005] Further, a highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 70 parts of high-density polyethylene resin, 1.3 parts of titanate coupling agent, 3.3 parts of polyimide, 2 parts of paraffin, 3 parts of glass flakes, 1.7 parts of talcum powder, 4.6 parts of antimony trioxide, 7 parts of corrosion-resistant material, 3.1 parts of composite fiber, 18 parts of thermoreversible crosslinking agent, 2 parts of crosslinking promoter.

[0006] Further, the corrosion-resistant material includes 4 parts of metallocene resin, 26 parts of waterborne polyurethane resin, and 3 parts of modified graphene.

[0007] Further, the modified graphene is obtained by grinding small flake graphene into powder, dispersing the powder in N,N-dimethylformamide solution to form a graphene dispersion, and then immersing the dispersion in hydrochloric acid with a volume fraction of 20-40%, reacting at 30-50 °C for 20-40 min. It can enhance the acid and alkali resistance of the pipe and has extremely strong corrosion resistance even in harsh environments such as humidity.

[0008] Further, the thermoreversible crosslinking agent is any one or a combination of several of sodium dicyclopentadiene dicarboxylate, potassium dicyclopentadiene dicarboxylate, and dicarboxylic acids with a dicyclopentadiene structure.

[0009] Further, the crosslinking promoter is any one or a combination of several of triethylenediamine, poly-1,2-butadiene, triphosphite, diallyl terephthalate, and nitroxide piperidinol.

[0010] Further, a preparation method of a highly corrosion-resistant HDPE double-wall corrugated pipe includes the following steps:

[0011] S1. Thermoreversible crosslinking of high-density polyethylene resin: Take the thermoreversible crosslinking agent and crosslinking promoter according to the above weight parts, stir and mix them evenly, add high-density polyethylene resin, and mix evenly at a high speed at a temperature of 220-250 °C to obtain crosslinked high-density polyethylene resin. First, crosslinking occurs, changing from the original two-dimensional structure to a three-dimensional network structure, which can improve the chemical resistance, heat resistance, and mechanical properties of polyethylene, thereby enhancing the corrosion resistance of the water pipe.

[0012] S2. Preparation of the base material layer: Mix titanate coupling agent, polyimide, paraffin, glass flakes, talcum powder, and antimony trioxide, pulverize them, grind at 60-80 °C, pass through a 80-120 mesh sieve, and add crosslinked high-density polyethylene resin and stir and mix evenly to obtain the base material layer.

[0013] S3. Preparation of the corrosion-resistant layer: Add corrosion-resistant materials and composite fibers to the base material layer, and stir and mix at 60-80 °C for 18-30 min to obtain the corrosion-resistant layer.

[0014] S4. Preparation of the pipe: Feed the corrosion-resistant layer into an extruder for heating and plasticization, and extrude and mold it to obtain a corrugated pipe blank. Then, feed it into a corrugated pipe forming machine for forming and flaring, and cool and shape it to obtain a rough corrugated pipe.

[0015] Preferably, the mixing speed in S1 is 500-700 rpm.

[0016] Preferably, the stirring rate in S2 is 400-700 rpm, and the stirring time is 30-60 min.

[0017] Preferably, the stirring rate in S3 is 300-500 rpm.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] For the HDPE double-wall corrugated pipe of the present invention, high-density polyethylene was originally selected as the main material, combined with raw materials such as corrosion-resistant materials, and scientifically proportioned to make it have better acid and alkali resistance. Among them, modified graphene can enhance the acid and alkali resistance of the pipe, and also has extremely strong corrosion resistance when used in harsh environments such as humidity;

[0020] Corrosion-resistant materials are added. The low surface tension of metallocene resin usually has good wettability and fluidity, which can better cover and penetrate the surface of the substrate, thereby improving the adhesion of the pipe. The resin with low surface tension can also reduce the defects and bubbles on the resin surface, improve the acid and alkali resistance of the pipe. The waterborne polyurethane resin molecule chain contains a large number of nitrogen-containing groups and hydrocarbon groups, which can chemically react with most chemical substances, thereby effectively inhibiting corrosion. The waterborne polyurethane resin is dispersed in each raw material, which can prevent moisture in the environment from penetrating into the interior of the material, thereby effectively preventing corrosion. The corrosion-resistant materials are made into anti-corrosion materials according to a specific ratio, and cooperate with high-density polyethylene to have strong anti-corrosion performance.

[0021] At the same time, the preparation method of the present invention has been improved in process. The high-density polyethylene resin is thermally reversibly crosslinked, changing its original two-dimensional structure into a three-dimensional network structure, which can improve the chemical resistance, heat resistance and mechanical properties of polyethylene, thereby improving the corrosion resistance of the water pipe. Specific Embodiments

[0022] In order to better understand the technical content of the present invention, specific embodiments are provided below to further illustrate the present invention.

[0023] The experimental methods used in the embodiments of the present invention are all conventional methods unless otherwise specified.

[0024] The materials, reagents, etc. used in the embodiments of the present invention can be obtained from commercial channels unless otherwise specified.

[0025] Example 1

[0026] A highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 50 parts of high-density polyethylene resin, 0.7 - part of titanate coupling agent, 3 parts of polyimide, 1 part of paraffin, 2 parts of glass flakes, 1.2 parts of talcum powder, 4 parts of antimony trioxide, 4 parts of corrosion-resistant material, 2.5 parts of composite fiber, 10 parts of thermoreversible crosslinking agent, 1 part of crosslinking promoter; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 3:1:2; the corrosion-resistant material includes 2 parts of metallocene resin, 20 parts of waterborne polyurethane resin, 1 part of modified graphene; the modified graphene is obtained by grinding small flake graphene into powder, dispersing the powder in N,N-dimethylformamide solution to form a graphene dispersion, then immersing it in hydrochloric acid with a volume fraction of 20%, and reacting at 30°C for 20 min. The above thermoreversible crosslinking agent is sodium dicyclopentadiene dicarboxylate, and the crosslinking promoter is triethylenediamine.

[0027] Example 2

[0028] A highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 80 parts of high-density polyethylene resin, 2.5 parts of titanate coupling agent, 4.2 parts of polyimide, 3 parts of paraffin, 5 parts of glass flakes, 2.3 parts of talcum powder, 5 parts of antimony trioxide, 10 parts of corrosion-resistant material, 3.5 parts of composite fiber, 26 parts of thermoreversible crosslinking agent, 3 parts of crosslinking promoter; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 5:4:4; the corrosion-resistant material includes 6 parts of metallocene resin, 35 parts of waterborne polyurethane resin, 5 parts of modified graphene; the modified graphene is obtained by grinding small flake graphene into powder, dispersing the powder in N,N-dimethylformamide solution to form a graphene dispersion, then immersing it in hydrochloric acid with a volume fraction of 40%, and reacting at 50°C for 40 min. The above thermoreversible crosslinking agent is sodium dicyclopentadiene dicarboxylate, and the crosslinking promoter is poly-1,2-butadiene.

[0029] Example 3

[0030] A highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 70 parts of high-density polyethylene resin, 1.3 parts of titanate coupling agent, 3.3 parts of polyimide, 2 parts of paraffin, 3 parts of glass flakes, 1.7 parts of talcum powder, 4.6 parts of antimony trioxide, 7 parts of corrosion-resistant material, 3.1 parts of composite fiber, 18 parts of thermoreversible crosslinking agent, and 2 parts of crosslinking accelerator; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 4:3:3; the corrosion-resistant material comprises 4 parts of metallocene resin, 26 parts of waterborne polyurethane resin, and 3 parts of modified graphene; the modified graphene is obtained by grinding small-layer graphene into powder, dispersing the powder in N,N-dimethylformamide solution to form a graphene dispersion, then immersing it in hydrochloric acid with a volume fraction of 30%, and reacting at 40°C for 30 min; the above thermoreversible crosslinking agent is dicyclopentadiene dimethyl potassium salt, and the crosslinking accelerator is poly-1,2-butadiene.

[0031] The above Examples 1-3 adopt the following preparation method:

[0032] S1. Thermoreversible crosslinking of high-density polyethylene resin: Take the thermoreversible crosslinking agent and crosslinking accelerator according to the above parts by weight, stir and mix them evenly, add high-density polyethylene resin, and mix them evenly at a temperature of 230°C and a rotation speed of 600 rpm to obtain crosslinked high-density polyethylene resin;

[0033] S2. Preparation of the base material layer: Take titanate coupling agent, polyimide, paraffin, glass flakes, talcum powder, and antimony trioxide, mix and crush them, grind them at 70°C, pass through a 100-mesh sieve, add crosslinked high-density polyethylene resin, and stir at a stirring rate of 500 rpm for 40 min to mix evenly and obtain the base material layer;

[0034] S3. Preparation of the corrosion-resistant layer: Add the corrosion-resistant material and composite fiber to the base material layer, and stir and mix at 70°C and a stirring rate of 400 rpm for 24 min to obtain the corrosion-resistant layer;

[0035] S4. Preparation of the pipe: Feed the corrosion-resistant layer into an extruder for heating and plasticization, and extrude and mold it to obtain a corrugated pipe blank, then feed it into a corrugated pipe forming machine for forming and flaring, and cool and shape it to obtain a rough corrugated pipe.

[0036] Example 4

[0037] A highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 50 parts of high-density polyethylene resin, 0.7 parts of titanate coupling agent, 3 parts of polyimide, 1 part of paraffin, 2 parts of glass flakes, 1.2 parts of talcum powder, 4 parts of antimony trioxide, 4 parts of corrosion-resistant material, 2.5 parts of composite fiber, 10 parts of thermoreversible crosslinking agent, and 1 part of crosslinking accelerator; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 3:1:2; the corrosion-resistant material includes 2 parts of metallocene resin, 20 parts of waterborne polyurethane resin, and 1 part of modified graphene; the modified graphene is obtained by grinding small lamellar graphene into powder, dispersing the powder in N,N-dimethylformamide solution to form a graphene dispersion, and then immersing it in hydrochloric acid with a volume fraction of 20%, and reacting at 30°C for 20 min; the above thermoreversible crosslinking agent is dicyclopentadiene dimethyl potassium salt, and the crosslinking accelerator is poly-1,2-butadiene.

[0038] The highly corrosion-resistant HDPE double-wall corrugated pipe adopts the following preparation method:

[0039] S1. Thermoreversible crosslinking of high-density polyethylene resin: Take the thermoreversible crosslinking agent and crosslinking accelerator according to the above parts by weight, stir and mix them evenly, add high-density polyethylene resin, and melt and extrude with a screw at a temperature of 220°C and a rotation speed of 500 rpm to obtain crosslinked high-density polyethylene resin;

[0040] S2. Preparation of the base material layer: Take titanate coupling agent, polyimide, paraffin, glass flakes, talcum powder, and antimony trioxide, mix and crush them, grind at 60°C, pass through an 80-mesh sieve, add crosslinked high-density polyethylene resin, and stir and mix evenly at a stirring rate of 400 pm for 30 min to obtain the base material layer;

[0041] S3. Preparation of the corrosion-resistant layer: Add the corrosion-resistant material and composite fiber to the base material layer, and stir and mix at 60°C and a rate of 300 rpm for 18 min to obtain the corrosion-resistant layer;

[0042] S4. Pipe preparation: Feed the corrosion-resistant layer into an extruder for heating and plasticization, and extrude and mold it to obtain a corrugated pipe blank, and then feed it into a corrugated pipe forming machine for forming and flaring, and cool and shape it to obtain a rough corrugated pipe.

[0043] Example 5

[0044] A highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 80 parts of high-density polyethylene resin, 2.5 parts of titanate coupling agent, 4.2 parts of polyimide, 3 parts of paraffin wax, 5 parts of glass flakes, 2.3 parts of talcum powder, 5 parts of antimony trioxide, 10 parts of corrosion-resistant material, 3.5 parts of composite fiber, 26 parts of thermoreversible crosslinking agent, and 3 parts of crosslinking accelerator; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 5:4:4; the corrosion-resistant material comprises 6 parts of metallocene resin, 35 parts of waterborne polyurethane resin, and 5 parts of modified graphene; the modified graphene is obtained by grinding small-layer graphene into powder, dispersing the powder in N,N-dimethylformamide solution to form a graphene dispersion, and then immersing it in hydrochloric acid with a volume fraction of 40% and reacting at 50°C for 40 min; the above thermoreversible crosslinking agent is dicyclopentadiene dimethyl potassium salt, and the crosslinking accelerator is poly-1,2-butadiene.

[0045] The highly corrosion-resistant HDPE double-wall corrugated pipe adopts the following preparation method:

[0046] S1. Thermoreversible crosslinking of high-density polyethylene resin: Take the thermoreversible crosslinking agent and crosslinking accelerator according to the above parts by weight, stir and mix them evenly, add high-density polyethylene resin, and melt and extrude it with a screw at a temperature of 250°C and a rotation speed of 700 rpm to obtain crosslinked high-density polyethylene resin;

[0047] S2. Preparation of the base material layer: Take titanate coupling agent, polyimide, paraffin wax, glass flakes, talcum powder, and antimony trioxide, mix, crush, grind at 80°C, pass through a 120-mesh sieve, add crosslinked high-density polyethylene resin, stir and mix evenly, with a stirring rate of 700 rpm and a stirring time of 60 min to obtain the base material layer;

[0048] S3. Preparation of the corrosion-resistant layer: Add the corrosion-resistant material and composite fiber to the base material layer, stir and mix at 80°C and a rate of 500 rpm for 30 min to obtain the corrosion-resistant layer;

[0049] S4. Pipe preparation: Feed the corrosion-resistant layer into an extruder for heating and plasticization, and extrude and mold it to obtain a corrugated pipe blank, then feed it into a corrugated pipe molding machine for molding and flaring, and cool and shape it to obtain a rough corrugated pipe.

[0050] Comparative Example 1

[0051] The difference between this comparative example and Example 3 is that: A highly corrosion-resistant HDPE double-wall corrugated pipe, comprising the following raw materials in parts by weight: 90 parts of high-density polyethylene resin, 0.5 part of titanate coupling agent, 1.2 parts of polyimide, 5 parts of paraffin wax, 8 parts of glass flakes, 3.2 parts of talcum powder, 5.0 parts of antimony trioxide, 2 parts of corrosion-resistant material, 2 parts of composite fiber, 6 parts of thermoreversible crosslinking agent, and 3 parts of crosslinking accelerator; the remaining operations are the same as those in Example 3.

[0052] Comparative Example 2

[0053] The difference between this comparative example and Example 3 is that no corrosion-resistant material is added to the raw materials in the HDPE double-wall corrugated pipe. The specific raw materials by weight are as follows: 70 parts of high-density polyethylene resin, 1.3 parts of titanate coupling agent, 3.3 parts of polyimide, 2 parts of paraffin, 3 parts of glass flakes, 1.7 parts of talcum powder, 4.6 parts of antimony trioxide, 3.1 parts of composite fiber, 18 parts of thermoreversible crosslinking agent, and 2 parts of crosslinking accelerator; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 4:3:3;

[0054] The preparation method is carried out according to the following steps

[0055] S1. Thermoreversible crosslinking of high-density polyethylene resin: Take the thermoreversible crosslinking agent and crosslinking accelerator according to the above weight parts, stir and mix them evenly, add the high-density polyethylene resin, and mix them evenly at a temperature of 230 °C and a rotation speed of 600 rpm to obtain crosslinked high-density polyethylene resin;

[0056] S2. Preparation of the base material layer: Take the titanate coupling agent, polyimide, paraffin, glass flakes, talcum powder, and antimony trioxide, mix them, crush them, grind them at 70 °C, pass through a 100-mesh sieve, add the crosslinked high-density polyethylene resin, and stir at a stirring rate of 500 rpm for 40 min to mix evenly and obtain the base material layer;

[0057] S3. Preparation of the corrosion-resistant layer: Add the composite fiber to the base material layer, and stir and mix at 70 °C and a stirring rate of 400 rpm for 24 min to obtain the corrosion-resistant layer;

[0058] S4. Preparation of the pipe: Feed the corrosion-resistant layer into an extruder for heating and plasticization, and extrude and mold it to obtain a corrugated pipe blank. Then, feed it into a corrugated pipe forming machine for forming and flaring, and cool and shape it to obtain a rough corrugated pipe.

[0059] Comparative Example 3

[0060] The difference between this comparative example and Example 3 is that the graphene is not modified.

[0061] Comparative Example 4

[0062] The difference between this comparative example and Example 3 is that in the preparation process, the high-density polyethylene resin does not undergo a crosslinking reaction.

[0063] I. Corrosion resistance test

[0064] The double-wall corrugated pipes prepared in the above Examples 1-5 and Comparative Examples 1-4 and the commercially available corrugated pipes were divided into 10 groups for testing. Each group was simultaneously immersed in hydrochloric acid, sulfuric acid, nitric acid, and sodium hydroxide with concentrations of 68%, 52%, 43%, and 48% for 112 days at an immersion temperature of 20-30°C. After the immersion, the change rates of tensile strength and elongation at break were measured;

[0065] The test results are as follows in the table:

[0066]

[0067] Result analysis:

[0068] The high corrosion-resistant HDPE double-wall corrugated pipe of the present invention selects specific materials and scientific ratios to synergistically exert its high corrosion-resistant effect. Combined with its preparation method, it enables high-efficiency corrosion resistance. Among them, the change rate of tensile strength of the Example group resistant to 68% hydrochloric acid is -4.6 to -2.5%, and the change rate of elongation at break is -4.5 to -3.0%. The change rate of tensile strength of the Example group resistant to 52% nitric acid is -4.9 to -2.7%, and the change rate of elongation at break is -4.7 to -2.9%. The change rate of tensile strength of the Example group resistant to 43% nitric acid is -2.6 to -2.2%, and the change rate of elongation at break is -2.9 to -1.2%. The change rate of tensile strength of the Example group resistant to 48% sodium hydroxide is -3.1 to -1.6%, and the change rate of elongation at break is -3.7 to -2.3%. It can be seen that the corrosion-resistant performance of the Example group is better, basically within 5%;

[0069] Compared with Comparative Example 1, the present invention uses high-density polyethylene as the main raw material, and combines with corrosion-resistant materials and other raw materials to improve its acid and alkali resistance; compared with Comparative Example 2, the addition of corrosion-resistant materials in the present invention has a significant corrosion-resistant effect. Modified graphene can enhance the acid and alkali resistance of the pipe, and also has extremely strong corrosion resistance when used in harsh environments such as humidity. Metallocene resin can improve the acid and alkali resistance of the pipe, and the corrosion-resistant material is prepared according to a specific ratio, which synergistically has strong corrosion resistance with high-density polyethylene resin; compared with Comparative Example 3, graphene is modified and covalently bonded with the dispersion liquid to enhance the three-dimensional spatial structure of graphene, which can exist stably and uniformly in the pipe raw material for a long time, and has good shielding effect and anti-corrosion performance; compared with Comparative Example 4, the cross-linking of high-density polyethylene resin changes the original two-dimensional structure into a three-dimensional network structure, which can improve the chemical resistance, heat resistance and mechanical properties of polyethylene, thereby improving the corrosion resistance of the water pipe.

[0070] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A highly corrosion-resistant HDPE double-wall corrugated pipe, characterized in that: It comprises the following raw materials in parts by weight: 50 - 80 parts of high - density polyethylene resin, 0.7 - 2.5 parts of titanate coupling agent, 3 - 4.2 parts of polyimide, 1 - 3 parts of paraffin, 2 - 5 parts of glass flakes, 1.2 - 2.3 parts of talcum powder, 4 - 5 parts of antimony trioxide, 4 - 10 parts of corrosion - resistant material, 2.5 - 3.5 parts of composite fiber, 10 - 26 parts of thermoreversible cross - linker, and 1 - 3 parts of cross - linking accelerator; the composite fiber is glass fiber, carbon fiber, and pearl fiber with a mass ratio of 3 - 5:1 - 4:2 - 4; the corrosion - resistant material comprises 2 - 6 parts of metallocene resin, 20 - 35 parts of water - borne polyurethane resin, and 1 - 5 parts of modified graphene; The modified graphene is obtained by grinding small - lamella graphene into powder, dispersing the powder in N,N - dimethylformamide solution to form a graphene dispersion, then immersing the dispersion in hydrochloric acid with a volume fraction of 20 - 40%, and reacting at 30 - 50 °C for 20 - 40 min. The preparation method of a highly corrosion - resistant HDPE double - wall corrugated pipe comprises the following steps: S1. Polyethylene thermoreversible cross - linking: Take the thermoreversible cross - linker and cross - linking accelerator according to the above parts by weight, stir and mix them evenly, add the high - density polyethylene resin, and mix them evenly at a high speed at a temperature of 220 - 250 °C to obtain cross - linked high - density polyethylene resin; S2. Substrate layer preparation: Take the titanate coupling agent, polyimide, paraffin, glass flakes, talcum powder, and antimony trioxide, mix them, crush them, grind them at 60 - 80 °C, pass through a 80 - 120 - mesh sieve, add the cross - linked high - density polyethylene resin, and stir and mix them evenly to obtain the substrate layer; S3. Corrosion - resistant layer preparation: Add the corrosion - resistant material and composite fiber to the substrate layer, stir and mix them at 60 - 80 °C for 18 - 30 min to obtain the corrosion - resistant layer; S4. Pipe preparation: Feed the corrosion - resistant layer into an extruder for heating and plasticizing, and extrude and form it to obtain a corrugated pipe blank, then feed it into a corrugated pipe forming machine for forming and flaring, and cool and shape it to obtain a rough corrugated pipe.

2. The high corrosion-resistant HDPE double-wall corrugated pipe according to claim 1, characterized in that: It comprises the following raw materials in parts by weight: 70 parts of high - density polyethylene resin, 1.3 parts of titanate coupling agent, 3.3 parts of polyimide, 2 parts of paraffin, 3 parts of glass flakes, 1.7 parts of talcum powder, 4.6 parts of antimony trioxide, 7 parts of corrosion - resistant material, 3.1 parts of composite fiber, 18 parts of thermoreversible cross - linker, and 2 parts of cross - linking accelerator.

3. The high-corrosion-resistant HDPE double-wall corrugated pipe according to claim 1, characterized in that: The corrosion - resistant material comprises 4 parts of metallocene resin, 26 parts of water - borne polyurethane resin, and 3 parts of modified graphene.

4. A highly corrosion-resistant HDPE double-wall corrugated pipe according to claim 1, characterized in that: The thermoreversible cross - linker is any one or a combination of several of sodium dicyclopentadiene dicarboxylate, potassium dicyclopentadiene dicarboxylate, and dicyclopentadiene - structured dicarboxylic acid.

5. The high corrosion-resistant HDPE double-wall corrugated pipe according to claim 1, characterized in that: The cross - linking accelerator is any one or a combination of several of triethylenediamine, poly - 1,2 - butadiene, trialkyl phosphite, diallyl terephthalate, and nitroxide piperidinol.

6. The high-corrosion-resistant HDPE double-wall corrugated pipe according to claim 1, wherein: The mixing speed in S1 is 500 - 700 rpm.

7. The high-corrosion-resistant HDPE double-wall corrugated pipe according to claim 1, characterized in that: The stirring rate in S2 is 400 - 700 rpm, and the stirring time is 30 - 60 min.

8. The high-corrosion-resistant HDPE double-wall corrugated pipe according to claim 1, characterized in that: The stirring rate in S3 is 300 - 500 rpm.

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