A modified high-density polyethylene pipe and its production process

Abstract

The present invention relates to a modified high-density polyethylene pipe and a production process thereof, and belongs to the technical field of special polyolefin pipes. The invention comprises, by weight, 100 parts of high-density polyethylene masterbatch, 15-22 parts of anti-fouling modifier, 1.1-1.4 parts of free radical initiator, 0.5-0.7 parts of lubricant, 0.12-0.16 parts of antioxidant, 0.01-0.02 parts of ultraviolet absorber and 0.01-0.02 parts of heat stabilizer; the anti-fouling modifier is an inorganic-organic composite, which reduces the migration of fluoride in the matrix and improves the compatibility with the matrix through block copolymerization, introduces a carbonyl ester structure to promote the formation of active sites, grafts the anti-fouling modifier with the matrix, exerts a stable anti-fouling and anti-scaling effect, and the inorganic nano-silica is connected to the matrix in the form of a covalent bond, fully exerts a strengthening effect, and has a significant promoting effect on the improvement of the mechanical properties of the pipe.

Description

Technical Field

[0001] The invention belongs to the technical field of special polyolefin pipes, and in particular, relates to a modified high-density polyethylene pipe and a production process thereof. Background Art

[0002] In the process of liquor production, many links involve the transportation and discharge of high-temperature liquids, such as high-temperature and high-pollution cooling water, and high-temperature weakly acidic and corrosive production wastewater. At present, ductile iron pipes lined with cement mortar pipelines are mainly used for transportation. Since the mortar is easily corroded by acidic sewage, and as the wastewater temperature drops, crystalline substances will precipitate, and the mortar layer is rough and easily corroded, the pipeline is seriously scaled, affecting the normal operation of the pipeline.

[0003] Polyolefin pipes have become the best substitute for ductile iron composite pipes due to their acid resistance, smooth surface, easy installation, and wide range of raw materials. Polyethylene, as a common polyolefin, has good acid and alkali resistance and solvent resistance, and is widely used in medium transportation pipelines. Polyethylene mainly includes three types: low-density polyethylene, high-density polyethylene, and linear low-density polyethylene. Among them, high-density polyethylene has strong mechanical properties, high softening point, and excellent chemical corrosion resistance. It is a better substitute for liquor wastewater transportation pipeline materials; in actual application, the scaling problem of ductile iron composite pipes has been alleviated compared to that of ductile iron composite pipes, but the scaling problem is still a pain point and difficulty of the production line. Therefore, this application aims to develop a modified high-density polyethylene pipe with anti-scaling performance. Summary of the invention

[0004] In order to solve the technical problems mentioned in the background technology, the purpose of the present invention is to provide a modified high-density polyethylene pipe and a production process thereof.

[0005] The purpose of the present invention can be achieved by the following technical solutions:

[0006] A modified high-density polyethylene pipe comprises, by weight, 100 parts of high-density polyethylene masterbatch, 15-22 parts of anti-fouling modifier, 1.1-1.4 parts of free radical initiator, 0.5-0.7 parts of lubricant, 0.12-0.16 parts of antioxidant, 0.01-0.02 parts of ultraviolet absorber and 0.01-0.02 parts of heat stabilizer.

[0007] The antifouling modifier is prepared by the following method:

[0008] Step A1: maleic anhydride, tetrafluorobutanediol, anhydrous sodium acetate and dimethylformamide are mixed, the temperature is raised to 85-95°C, mechanical stirring is performed at 80-120 rpm, and the mixture is stirred and reacted for 1.2-1.5 hours. Excess maleic anhydride and tetrafluorobutanediol form a fluorine-containing low molecular weight polyester under the catalysis of anhydrous sodium acetate. 1,4-butanediol is then added and mixed, the temperature is raised to 102-108°C, the stirring rate is increased to 150-200 rpm, the mixture is stirred and reacted for 1.5-2 hours. 1,4-butanediol is used as a connecting material and a capping agent to continue to react with the small molecular weight polyester. After the reaction is completed, low boiling points are removed by vacuum rotary evaporation to obtain an intermediate;

[0009] Furthermore, the usage ratio of maleic anhydride, tetrafluorobutanediol, 1,4-butanediol and anhydrous sodium acetate is 0.1 mol: 0.05-0.08 mol: 0.07-0.1 mol: 0.14-0.18 g.

[0010] Step A2: the intermediate, triethylamine and tetrahydrofuran are mixed, the temperature is kept constant at 10-20°C, stirring is applied at 200-300 rpm, allyl chloride is slowly added, and the reaction time is controlled to be 3-4 hours, the allyl chloride reacts with the terminal hydroxyl group of the intermediate to modify the intermediate, and a large amount of deionized water is added for washing after the reaction is completed, and the organic phase is taken and rotary evaporated under reduced pressure to obtain a prepolymer monomer;

[0011] Furthermore, the usage ratio of the intermediate, allyl chloride and triethylamine is 100 g: 35-40 mmol: 6-8 mL.

[0012] Step A3: nano-silica, silane coupling agent KH560 and ethanol aqueous solution are mixed, stirred at room temperature for 12 hours, centrifuged to obtain bottom precipitate for washing, silane coupling agent KH560 is used for coupling treatment of nano-silica, epoxy groups are introduced on the surface for modification, undecenol, triethylenediamine and dioxane are added and mixed, the temperature is raised to 105-110° C., mechanically stirred at 120-150 rpm, and the mixture is refluxed for 1.8-2.2 hours. Under the catalysis of triethylenediamine, undecenol reacts with the surface epoxy groups of nano-silica for ring-opening reaction. After the reaction is completed, the bottom precipitate is centrifuged to obtain, washed with ethanol, and dried to obtain a loaded monomer;

[0013] Furthermore, the usage ratio of nano-silica, silane coupling agent KH560, undecenyl alcohol and triethylenediamine is 50g:15-20mL:6-8mL:0.3-0.4g.

[0014] Step A4: prepolymer monomer, load monomer, azobisisobutyronitrile and cyclohexane are mixed, the temperature is raised to 60-70°C, mechanically stirred at 120-180 rpm, and the reaction is kept warm for 2.5-3 hours. Under the initiation of azobisisobutyronitrile, the prepolymer monomer and the load monomer undergo an addition reaction to graft the prepolymer monomer onto the load monomer. After the reaction is completed, the cyclohexane is removed by vacuum rotary evaporation to obtain an anti-fouling modifier;

[0015] Furthermore, the usage ratio of the prepolymer monomer, the loaded monomer and azobisisobutyronitrile is 100g:20-50g:1.3-1.7g.

[0016] Furthermore, the free radical initiator is dicumyl peroxide.

[0017] Furthermore, the lubricant is ethylene-octene copolymer.

[0018] A production process for a modified high-density polyethylene pipe specifically includes the following steps:

[0019] Step S1: adding high-density polyethylene masterbatch, anti-fouling modifier, free radical initiator, lubricant, antioxidant, ultraviolet absorber and heat stabilizer, premixing and uniformly obtaining a compound;

[0020] Step S2: Extruding the compound material into a pipe extruder, the temperature of each temperature zone of the pipe extruder is set to: 140-160°C for zone 1, 160-180°C for zone 2, 180-200°C for zone 3, 200°C for zone 4, and 160°C for die head. After cooling, a modified high-density polyethylene pipe is obtained.

[0021] Beneficial effects of the present invention:

[0022] The invention uses a self-made anti-fouling modifier to modify high-density polyethylene to obtain a pipe with excellent anti-fouling effect. The anti-fouling modifier is formed by excess maleic anhydride and tetrafluorobutanediol under the catalysis of anhydrous sodium acetate to form a fluorine-containing low-molecular-weight polyester, and then 1,4-butanediol is used as a connecting material and a capping agent to continue to react with the small-molecule polyester to prepare an intermediate with an alcohol hydroxyl end capping and a side chain fluorine-containing group, and then allyl chloride reacts with the end hydroxyl group of the intermediate to modify the end of the intermediate molecular chain with a double bond to prepare a prepolymer monomer; nano-silicon dioxide is modified by a silane coupling agent KH560, epoxy group modification is introduced on the surface, and then undecenol is reacted with the surface epoxy group of the nano-silicon dioxide by triethylenediamine catalysis to introduce olefin chains and double bond modification to the surface to prepare a loaded monomer; finally, azobisisobutyronitrile is added to the nano-silicon dioxide to form a prepolymer monomer. Under initiation, the prepolymer monomer and the load monomer undergo addition reaction, and the prepolymer monomer is grafted onto the load monomer, and the obtained anti-fouling modifier is an inorganic-organic composite; wherein, the prepolymer monomer forms a high molecular weight compound by block copolymerization, which reduces the migration of fluoride in the high-density polyethylene matrix and improves the compatibility with the matrix. At the same time, the introduction of the carbonyl ester structure is conducive to the attack of the free radical initiator to form free radicals, and produces multiple active sites, making it easier for the anti-fouling modifier to graft with the matrix, and fix the anti-fouling modifier on the macromolecular chain of the matrix, thereby exerting a stable anti-fouling and anti-scaling effect; the load monomer has a higher compatibility with the matrix through the modification of olefin chains and double bonds, and the inorganic nano-silica is connected to the matrix by covalent bonds, giving full play to the strengthening effect, which has a significant promoting effect on the improvement of the mechanical properties of the pipe. DETAILED DESCRIPTION

[0023] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0024] Example 1

[0025] This embodiment prepares a modified high-density polyethylene tube, and the specific implementation process is as follows:

[0026] 1) Preparation of antifouling modifier

[0027] 1.1. Take maleic anhydride, tetrafluorobutanediol and anhydrous sodium acetate as feed materials, then add dimethylformamide in an amount 1.2 times the mass of the substrate and mix, stir and heat the reaction system until the temperature reaches 85°C, supplemented with 80rpm mechanical stirring, keep warm and stir for 1.5h, then add 1,4-butanediol and mix, continue to heat to 102°C, increase the stirring rate to 150rpm, keep warm and stir for 2h, in the reaction, the amount ratio of maleic anhydride, tetrafluorobutanediol, 1,4-butanediol and anhydrous sodium acetate is 0.1mol: 0.05mol: 0.1mol: 0.14g, after the reaction is completed, remove the low-boiling substances mainly composed of 1,4-butanediol under reduced pressure to obtain an intermediate.

[0028] 1.2. Take the intermediate and triethylamine as feed materials, add tetrahydrofuran 0.8 times the mass of the substrate to dilute, keep the temperature at 20°C, apply stirring at 200rpm, slowly add allyl chloride within 2h, keep the temperature and stir to react after adding, and control the total reaction time to be 4h. During the reaction, the amount ratio of the intermediate, allyl chloride and triethylamine is 100g:35mmol:6mL. After the reaction is completed, add deionized water 5 times the mass of the reaction substrate to wash, take the organic phase and dehydrate it by vacuum rotary evaporation to obtain a prepolymer monomer.

[0029] 1.3. Take nano-silica and silane coupling agent KH560 as feed materials, then add ethanol aqueous solution with twice the mass of substrate and volume concentration of 30%, stir at 60rpm at room temperature for 12h, centrifuge to get the bottom precipitate, wash it with deionized water, centrifuge to get the precipitate again, add undecenol, triethylenediamine and 1.5 times the mass of dioxane of the precipitate, mix, heat to 105℃, stir mechanically at 120rpm, keep warm and reflux for 2.2h. In the reaction, the amount ratio of nano-silica, silane coupling agent KH560, undecenol and triethylenediamine is 50g:15mL:6mL:0.3g. After the reaction, centrifuge to get the bottom precipitate, wash it with ethanol, centrifuge to get the precipitate again, place it in a drying oven at 60℃ for 2h to obtain the loaded monomer.

[0030] 1.4. Take the prepolymer monomer, the load monomer and azobisisobutyronitrile as feed materials, add cyclohexane 1.5 times the mass of the substrate, mix, heat to 60°C, stir mechanically at 120rpm, and keep warm for 3 hours. During the reaction, the amount ratio of the prepolymer monomer, the load monomer and azobisisobutyronitrile is 100g:20g:1.7g. After the reaction, remove the cyclohexane by reduced pressure rotary evaporation to obtain an anti-fouling modifier.

[0031] 2) Preparation of modified high-density polyethylene pipe

[0032] 2.1 Ingredients: Take the following raw materials by weight:

[0033] 100 parts of high-density polyethylene masterbatch, model 8050;

[0034] 18 parts of antifouling modifier, prepared in this example;

[0035] 1.1 parts of free radical initiator, selected from dicumyl peroxide, industrial grade raw material;

[0036] 0.5 parts of lubricant, selected from ethylene-octene copolymer, model 871L;

[0037] 0.15 parts of antioxidant, selected from antioxidant 1076;

[0038] 0.02 parts of ultraviolet absorber, selected from ultraviolet absorber UV-0;

[0039] 0.01 part of heat stabilizer, selected from JX-181 organic tin heat stabilizer;

[0040] Add the above raw materials into a stirrer and mix well to obtain a batch material.

[0041] 2.2. Melt extrusion: The compound material is extruded by a pipe extruder, which is provided with four temperature zones. The temperature of each temperature zone is set as follows: zone 1 140-160°C, zone 2 160-180°C, zone 3 temperature 180-200°C, zone 4 temperature 200°C, and the head temperature is set to 160°C. After extrusion, the material is cooled to obtain a modified high-density polyethylene pipe.

[0042] Example 2

[0043] This embodiment prepares a modified high-density polyethylene tube, and the specific implementation process is as follows:

[0044] 1) Preparation of antifouling modifier

[0045] 1.1. Take maleic anhydride, tetrafluorobutanediol and anhydrous sodium acetate as feed materials, then add dimethylformamide in an amount 1.2 times the mass of the substrate and mix, stir and heat the reaction system until the temperature reaches 95°C, supplemented with mechanical stirring at 120rpm, and stir and react for 1.2h at this temperature, then add 1,4-butanediol and mix, continue to heat to 108°C, increase the stirring rate to 200rpm, and stir and react for 1.5h at this temperature. During the reaction, the amount ratio of maleic anhydride, tetrafluorobutanediol, 1,4-butanediol and anhydrous sodium acetate is 0.1mol: 0.08mol: 0.07mol: 0.18g. After the reaction is completed, the low-boiling substances mainly composed of 1,4-butanediol are removed under reduced pressure to obtain an intermediate.

[0046] 1.2. Take the intermediate and triethylamine as feed materials, add tetrahydrofuran 1.1 times the mass of the substrate to dilute, keep the temperature at 10°C, apply stirring at 300rpm, slowly add allyl chloride within 1.5h, keep warm and stir to react after adding, and control the total addition reaction time to be 3h. During the reaction, the amount ratio of the intermediate, allyl chloride and triethylamine is 100g:40mmol:8mL. After the reaction is completed, add deionized water 5 times the mass of the reaction substrate to wash, take the organic phase and dehydrate it by vacuum rotary evaporation to obtain a prepolymer monomer.

[0047] 1.3. Take nano-silica and silane coupling agent KH560 as feed materials, and then add ethanol aqueous solution with 3 times the mass of the substrate and a volume concentration of 30%, stir at 60rpm at room temperature for 12h, centrifuge to take the bottom precipitate, wash it with deionized water, centrifuge again to take the precipitate, add undecenol, triethylenediamine and 1.5 times the mass of dioxane of the precipitate, mix, heat to 110℃, stir mechanically at 150rpm, keep warm and reflux for 1.8h. During the reaction, the amount ratio of nano-silica, silane coupling agent KH560, undecenol and triethylenediamine is 50g:20mL:8mL:0.4g. After the reaction, centrifuge to take the bottom precipitate, wash it with ethanol, centrifuge again to take the precipitate, place it in a drying oven at 60℃ for 2h to obtain the loaded monomer.

[0048] 1.4. Take the prepolymer monomer, the load monomer and azobisisobutyronitrile as feed materials, add cyclohexane twice the mass of the substrate, mix, heat to 70°C, stir mechanically at 180rpm, and keep warm for 2.5h. During the reaction, the amount ratio of the prepolymer monomer, the load monomer and azobisisobutyronitrile is 100g:50g:1.3g. After the reaction, remove the cyclohexane by reduced pressure rotary evaporation to obtain an anti-fouling modifier.

[0049] 2) Preparation of modified high-density polyethylene pipe

[0050] 2.1 Ingredients: Take the following raw materials by weight:

[0051] 100 parts of high-density polyethylene masterbatch, model 8050;

[0052] 22 parts of antifouling modifier, prepared in this example;

[0053] 1.4 parts of free radical initiator, selected from dicumyl peroxide, industrial grade raw material;

[0054] 0.7 parts of lubricant, selected from ethylene-octene copolymer, model 871L;

[0055] 0.12 parts of antioxidant, selected from antioxidant 1076;

[0056] 0.012 parts of ultraviolet absorber, selected from ultraviolet absorber UV-0;

[0057] 0.02 parts of heat stabilizer, selected from JX-181 organic tin heat stabilizer;

[0058] Add the above raw materials into a stirrer and mix well to obtain a batch material.

[0059] 2.2. Melt extrusion: The compound material is extruded by a pipe extruder, which is provided with four temperature zones. The temperature of each temperature zone is set as follows: zone 1 140-160°C, zone 2 160-180°C, zone 3 temperature 180-200°C, zone 4 temperature 200°C, and the head temperature is set to 160°C. After extrusion, the material is cooled to obtain a modified high-density polyethylene pipe.

[0060] Example 3

[0061] This embodiment prepares a modified high-density polyethylene tube, and the specific implementation process is as follows:

[0062] 1) Preparation of antifouling modifier

[0063] 1.1. Take maleic anhydride, tetrafluorobutanediol and anhydrous sodium acetate as feed materials, then add dimethylformamide in an amount 1.2 times the mass of the substrate and mix, stir and heat the reaction system until the temperature reaches 92°C, supplemented with mechanical stirring at 120rpm, and stir and react for 1.4h at this temperature, then add 1,4-butanediol and mix, continue to heat to 105°C, increase the stirring rate to 150rpm, and stir and react for 1.6h at this temperature. During the reaction, the amount ratio of maleic anhydride, tetrafluorobutanediol, 1,4-butanediol and anhydrous sodium acetate is 0.1mol: 0.07mol: 0.07mol: 0.16g. After the reaction is completed, the low-boiling substances mainly composed of 1,4-butanediol are removed under reduced pressure to obtain an intermediate.

[0064] 1.2. Take the intermediate and triethylamine as feed materials, add tetrahydrofuran of the same mass as the substrate to dilute, keep the temperature at 10°C, apply stirring at 300rpm, slowly add allyl chloride within 1.5h, keep warm and stir to react after adding, and control the total reaction time to be 3.5h. During the reaction, the amount ratio of the intermediate, allyl chloride and triethylamine is 100g:35mmol:7mL. After the reaction is completed, add deionized water 5 times the mass of the reaction substrate to wash, take the organic phase and dehydrate it by vacuum rotary evaporation to obtain a prepolymer monomer.

[0065] 1.3. Take nano-silica and silane coupling agent KH560 as feed materials, then add ethanol aqueous solution with 3 times the mass of the substrate and a volume concentration of 30%, stir at 60rpm at room temperature for 12h, centrifuge to take the bottom precipitate, wash it with deionized water, centrifuge to take the precipitate again, add undecenol, triethylenediamine and 1.5 times the mass of dioxane of the precipitate, mix, heat to 108℃, stir mechanically at 150rpm, keep warm and reflux for 2h. In the reaction, the amount ratio of nano-silica, silane coupling agent KH560, undecenol and triethylenediamine is 50g:18mL:7mL:0.4g. After the reaction, centrifuge to take the bottom precipitate, wash it with ethanol, centrifuge to take the precipitate again, place it in a drying oven at 60℃ for 2h to obtain the loaded monomer.

[0066] 1.4. Take the prepolymer monomer, the load monomer and azobisisobutyronitrile as feed materials, add cyclohexane 1.5 times the mass of the substrate, mix, heat to 62°C, stir mechanically at 180rpm, and keep warm for 2.6h. During the reaction, the amount ratio of the prepolymer monomer, the load monomer and azobisisobutyronitrile is 100g:35g:1.5g. After the reaction is completed, remove the cyclohexane by reduced pressure rotary evaporation to obtain an anti-fouling modifier.

[0067] 2) Preparation of modified high-density polyethylene pipe

[0068] 2.1 Ingredients: Take the following raw materials by weight:

[0069] 100 parts of high-density polyethylene masterbatch, model 8050;

[0070] 15 parts of antifouling modifier, prepared in this example;

[0071] 1.2 parts of free radical initiator, selected from dicumyl peroxide, industrial grade raw material;

[0072] 0.6 parts of lubricant, selected from ethylene-octene copolymer, model 871L;

[0073] 0.16 parts of antioxidant, selected from antioxidant 1076;

[0074] 0.02 parts of ultraviolet absorber, selected from ultraviolet absorber UV-0;

[0075] 0.01 part of heat stabilizer, selected from JX-181 organic tin heat stabilizer;

[0076] Add the above raw materials into a stirrer and mix well to obtain a batch material.

[0077] 2.2. Melt extrusion: The compound material is extruded by a pipe extruder, which is provided with four temperature zones. The temperature of each temperature zone is set as follows: zone 1 140-160°C, zone 2 160-180°C, zone 3 temperature 180-200°C, zone 4 temperature 200°C, and the head temperature is set to 160°C. After extrusion, the material is cooled to obtain a modified high-density polyethylene pipe.

[0078] Comparative Example

[0079] This comparative example is a commercially available HDPE flat-wall pipe provided by a Shandong Plastic Products Co., Ltd.

[0080] Take the modified high-density polyethylene pipes prepared in Examples 1 to 3 and the HDPE flat-wall pipe provided in the comparative example, cut a sample with a length of 100 mm, and perform a scaling test on the sample. The specific test method is as follows:

[0081] The concentrated wastewater from a winery in Sichuan was taken as the test material. The roughness of the inner wall of the sample was tested and each sample was weighed. Then the sample was filled with wastewater and sealed at both ends with glass plugs. The sample was placed in a constant temperature box at 50°C and left to stand horizontally for 20 days, 50 days and 80 days respectively. The sample was taken out and the wastewater was discharged. The sample was placed in a drying oven at 60°C for 2 hours and then weighed again to calculate the amount of scaling. The specific test data are shown in Table 1:

[0082] Table 1

[0083]

[0084]

[0085] It can be seen from the data in Table 1 that the modified high-density polyethylene pipe prepared in the present invention has excellent anti-scaling performance compared with existing pipes.

[0086] Samples were taken from the modified high-density polyethylene pipes prepared in Examples 1 to 3 and the HDPE flat-wall pipes provided in the comparative example, and tensile tests were performed according to the GB / T 1040.2-2022 standard, and impact tests were performed according to the GB / T1843-2008 standard. The specific test data are shown in Table 2:

[0087] Table 2

[0088]

[0089] It can be seen from the data in Table 2 that the modified high-density polyethylene pipe prepared in the present invention has better tensile properties than existing pipes, and its impact strength is similar to that of existing pipes.

[0090] Samples were taken from the modified high-density polyethylene pipes prepared in Examples 1 to 3 and the HDPE flat-wall pipes provided in the comparative example, and the pipe performance was tested in accordance with the YD / T841.1-2016 standard. The specific test data are shown in Table 3:

[0091] Table 3

[0092]

[0093] It can be seen from the data in Table 3 that the modified high-density polyethylene pipe prepared in the present invention meets the pipe use standards and has a relatively high ring stiffness compared to existing pipes.

[0094] In the description of the specification, the description with reference to the terms "one embodiment", "example", "specific example", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0095] The above contents are merely examples and explanations of the present invention. Those skilled in the art may make various modifications or additions to the specific embodiments described or replace them in a similar manner. As long as they do not deviate from the invention or exceed the scope defined by the claims, they shall all fall within the protection scope of the present invention.

Claims

1. A modified high-density polyethylene pipe, characterized in that: The composition comprises, by weight: 100 parts of high-density polyethylene masterbatch, 15-22 parts of antifouling modifier, 1.1-1.4 parts of free radical initiator, 0.5-0.7 parts of ethylene-octene copolymer, 0.12-0.16 parts of antioxidant, 0.01-0.02 parts of ultraviolet absorber and 0.01-0.02 parts of heat stabilizer; The antifouling modifier is prepared by the following method: Step A1: maleic anhydride, tetrafluorobutanediol, anhydrous sodium acetate and dimethylformamide are mixed, the temperature is raised to 85-95°C, the mixture is stirred and kept warm for 1.2-1.5 hours, 1,4-butanediol is added and mixed, the temperature is raised to 102-108°C, the mixture is stirred and kept warm for 1.5-2 hours, and low-boiling substances are removed by vacuum rotary evaporation after the reaction is completed to obtain an intermediate, wherein the amount ratio of maleic anhydride, tetrafluorobutanediol, 1,4-butanediol and anhydrous sodium acetate is 0.1 mol: 0.05-0.08 mol: 0.07-0.1 mol: 0.14-0.18 g; Step A2: The intermediate, triethylamine and tetrahydrofuran are mixed, kept at a constant temperature of 10-20°C, stirred and allyl chloride is slowly added, and the reaction time is controlled to be 3-4h. After the reaction is completed, deionized water is added for washing, and the organic phase is taken and vacuum rotary evaporated to obtain a prepolymer monomer, wherein the amount ratio of the intermediate, allyl chloride and triethylamine is 100g:35-40mmol:6-8mL; Step A3: nano-silica, silane coupling agent KH560 and ethanol aqueous solution are mixed, stirred at room temperature for 12 hours, centrifuged to obtain a precipitate for washing, undecenol, triethylenediamine and dioxane are added and mixed, the temperature is raised to 105-110° C., stirred, kept warm and refluxed for 1.8-2.2 hours, and after the reaction is completed, the precipitate is centrifuged, washed and dried to obtain a loaded monomer, wherein the amount ratio of nano-silica, silane coupling agent KH560, undecenol and triethylenediamine is 50g:15-20mL:6-8mL:0.3-0.4g; Step A4: Mix the prepolymer monomer, the loaded monomer, azobisisobutyronitrile and cyclohexane, raise the temperature to 60-70°C, stir and keep warm for 2.5-3h, and perform vacuum rotary evaporation after the reaction to obtain an anti-fouling modifier, wherein the amount ratio of the prepolymer monomer, the loaded monomer and azobisisobutyronitrile is 100g:20-50g:1.3-1.7g.

2. The modified high-density polyethylene pipe according to claim 1, characterized in that: The free radical initiator is dicumyl peroxide.

3. The production process of a modified high-density polyethylene pipe according to claim 1, characterized in that: Including the following processes: Step S1: premixing the raw materials uniformly according to the weight ratio to obtain a batch material; Step S2: Extruding the compound material into a pipe extruder, the temperature of each temperature zone of the pipe extruder is set to: 140-160°C for zone 1, 160-180°C for zone 2, 180-200°C for zone 3, 200°C for zone 4, and 160°C for die head. After cooling, a modified high-density polyethylene pipe is obtained.

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