High-puncture-resistance polyethylene geomembrane as well as production device and production process thereof

Abstract

The invention discloses a high-puncture-resistance polyethylene geomembrane as well as a production device and a production process thereof, and belongs to the technical field of geomembranes. The high-puncture-resistance polyethylene geomembrane comprises an upper-layer membrane, a first middle-layer membrane, an inner-layer membrane, a second middle-layer membrane and a lower-layer membrane from top to bottom, each of the upper-layer film and the lower-layer film comprises the following components in parts by weight: 90-100 parts of modified linear low-density polyethylene resin and 2-10 parts of double-resistance black master batch; each of the first middle-layer film and the second middle-layer film comprises 40-60 parts of medium-density polyethylene resin, 35-55 parts of metallocene high-density polyethylene resin and 2-10 parts of double-resistance black master batch; and the inner-layer film comprises 60-80 parts of medium-density polyethylene resin, 15-35 parts of linear low-density polyethylene resin and 2-10 parts of double-resistance black master batch. The polyethylene geomembrane is of a symmetrical five-layer membrane structure with the inner layer membrane as the center, the components of all the layers and the proportional relation between the components are specifically limited, the puncture resistance and the environmental stress cracking resistance of the polyethylene geomembrane are synchronously improved, and the requirements of severe environment anti-seepage engineering are met.

Description

Technical Field

[0001] The present application relates to a highly puncture-resistant polyethylene geomembrane and a production device and a production process thereof, belonging to the technical field of geomembranes. Background Art

[0002] At present, the flexible cushion used in landfill anti-seepage and tailings pond anti-seepage as the main anti-seepage layer is mainly polyethylene geomembrane. In some anti-seepage projects, the foundation conditions are not ideal, and there are many sharp-angled gravels in the compacted soil layer, which poses a great risk of forming holes during the laying of the geomembrane; the environmental conditions are complex, which is a great test for the environmental stress cracking resistance of the geomembrane; in addition, after the geomembrane is laid on the protective layer, a leachate gravel diversion layer is generally laid on top of the geotextile, and there may be sharp-angled gravel in the gravel layer. Although there is a geotextile as a protective layer, the safety factor of the integrity of the geomembrane is greatly reduced under the high pressure of the garbage pile; on the other hand, for landfill anti-seepage, there are inevitably sharp objects in the backfill garbage after the landfill is put into operation, which puts higher requirements on the puncture resistance of the geomembrane under the high pressure of the garbage pile.

[0003] The raw materials of composite geomembranes in the prior art are generally selected from high-density polyethylene or linear low-density polyethylene as raw materials, which are sent to an extruder after screening, cleaning, drying and other treatments to prepare geomembranes. However, the geomembranes prepared in the prior art are difficult to take into account both puncture resistance and environmental stress cracking resistance, and are difficult to be applied to anti-seepage projects in harsh environments. Therefore, how to provide a polyethylene geomembrane that meets both puncture resistance and environmental stress cracking resistance in harsh environment anti-seepage projects is an urgent problem to be solved. Summary of the invention

[0004] In order to solve the above problems, a high puncture-resistant polyethylene geomembrane and its production device and production process are provided. The present application forms a polyethylene geomembrane with a symmetrical five-layer membrane structure centered on the inner membrane by arranging an upper membrane, a first middle membrane, an inner membrane, a second middle membrane and a lower membrane in sequence from top to bottom, and specifically defines the components of each layer and the proportional relationship between the components, thereby simultaneously improving the puncture resistance and environmental stress cracking resistance of the polyethylene geomembrane to meet the needs of anti-seepage projects in harsh environments.

[0005] According to one aspect of the present application, a high puncture-resistant polyethylene geomembrane is provided, which comprises, from top to bottom, an upper film, a first middle film, an inner film, a second middle film and a lower film; in terms of weight percentage, the upper film and the lower film both comprise 90 to 100 parts of modified linear low-density polyethylene resin and 2 to 10 parts of double-resistant black masterbatch; the first middle film and the second middle film both comprise 40 to 60 parts of medium-density polyethylene resin, 35 to 55 parts of metallocene high-density polyethylene resin and 2 to 10 parts of double-resistant black masterbatch; the inner film comprises 60 to 80 parts of medium-density polyethylene resin, 15 to 35 parts of linear low-density polyethylene resin and 2 to 10 parts of double-resistant black masterbatch.

[0006] Preferably, in terms of weight parts, the upper film and the lower film each include 95 parts of modified linear low-density polyethylene resin and 5 parts of double-anti-black masterbatch; the first middle layer film and the second middle layer film each include 50 parts of medium-density polyethylene resin, 45 parts of metallocene high-density polyethylene resin and 5 parts of double-anti-black masterbatch; the inner layer film includes 70 parts of medium-density polyethylene resin, 25 parts of linear low-density polyethylene resin and 5 parts of double-anti-black masterbatch.

[0007] Specifically, the present application includes an upper film, a first middle film, an inner film, a second middle film and a lower film from top to bottom, forming a symmetrical film structure centered on the inner film; in the upper film and the lower film, the modified linear low-density polyethylene resin is toughened and strengthened, and then acts together with the double-resistant black masterbatch to make the upper film and the lower film have high stiffness, high tensile strength and high puncture resistance, and excellent flexibility and environmental stress cracking resistance; the first middle film and the second middle film are made of medium-density polyethylene resin, metallocene high-density polyethylene resin and double-resistant black masterbatch. The metallocene high-density polyethylene has high rigidity and high tensile modulus, and is resistant to puncture. It has excellent puncture resistance, but poor environmental stress cracking resistance. It works together with a specific proportion of medium-density polyethylene resin and double-resistant black masterbatch to give it excellent puncture resistance, good environmental stress cracking resistance and tearing resistance. The inner membrane adopts medium-density polyethylene resin, linear low-density polyethylene resin and double-resistant black masterbatch to improve the flexibility of the geomembrane while taking into account the rigidity requirements of the geomembrane. This application adopts a symmetrical five-layer membrane structure to work together, so that the geomembrane has good environmental stress cracking resistance and tearing resistance on the basis of excellent puncture resistance, and can adapt to harsh environment anti-seepage projects.

[0008] Optionally, in parts by weight, the modified linear low-density polyethylene resin includes 80 to 100 parts of linear low-density polyethylene resin, 5 to 15 parts of modified nano-silicon dioxide, 5 to 10 parts of nano-titanium dioxide, 2 to 8 parts of maleic anhydride grafted polyethylene, 0.5 to 1.5 parts of antioxidant, and 0.05 to 0.1 parts of ultraviolet absorber; the modified nano-silicon dioxide is prepared by modification with a silane coupling agent.

[0009] Specifically, the preparation method of the modified linear low-density polyethylene resin comprises the following steps:

[0010] S01: uniformly mixing modified nano silicon dioxide, nano titanium dioxide, maleic anhydride grafted polyethylene, antioxidant, and ultraviolet absorber according to a certain proportion to obtain a premix;

[0011] S02: adding the premix to the linear low-density polyethylene resin and extruding the mixture using a twin-screw extruder at a temperature of 180-220°C;

[0012] S03 is cooled and granulated to obtain a modified linear low-density polyethylene resin.

[0013] Specifically, in the present application, a modified linear low-density polyethylene resin is obtained by modification of the linear low-density polyethylene, the strength and toughness of which are improved, and it works together with the double-resistant black masterbatch to ensure the puncture resistance, oxidation resistance and environmental stress cracking resistance of the geomembrane; on the one hand, a specific proportion of modified nano-silica and nano-titanium dioxide and maleic anhydride grafted polyethylene work synergistically to improve its mechanical properties and toughness; on the other hand, the modified nano-silica effectively improves the dispersibility and compatibility of the nano-silica, further enhancing the modification effect.

[0014] Optionally, the preparation method of the modified nano-silicon dioxide comprises the following steps:

[0015] (1) dispersing nano-silicon dioxide in ethanol to obtain a nano-silicon dioxide dispersion;

[0016] (2) adding a silane coupling agent to the nano-silicon dioxide dispersion, heating and stirring;

[0017] (3) Centrifugation and vacuum drying to obtain modified nano-silica.

[0018] Specifically, the mass ratio of nano-silicon dioxide to ethanol is 1:(300-400), and the volume fraction of the silane coupling agent is 1.5% to 2%.

[0019] Specifically, the dispersion time in step (1) is 25 to 35 minutes; the temperature in step (2) is 60 to 75° C., and the stirring time is 3 to 4 hours; the centrifugal speed in step (3) is 7500 to 8500 rpm, and the vacuum drying is 45 to 55° C. for 24 to 36 hours.

[0020] Specifically, the silane coupling agent is an aminosilane coupling agent.

[0021] Specifically, the aminosilane coupling agent is 3-aminopropyltriethoxysilane or N-(2-aminoethyl)-3-aminopropyltrimethoxysilane.

[0022] Preferably, the aminosilane coupling agent is 3-aminopropyltriethoxysilane.

[0023] Specifically, the aminosilane coupling agent can introduce amine groups into the nano-silica, which helps to improve the dispersibility of the nano-silica, avoid its agglomeration, and further enhance the modification effect.

[0024] According to another aspect of the present application, a production device for the above-mentioned high puncture-resistant polyethylene geomembrane is also provided, which comprises a centralized feeding mechanism, a melt extrusion mechanism, a mold forming mechanism, an internal cooling control mechanism and a traction and rolling mechanism in sequence; the centralized feeding mechanism comprises a first feeding component, a second feeding component, a third feeding component, a fourth feeding component and a fifth feeding component.

[0025] Specifically, the production device of high puncture-resistant polyethylene geomembrane provided in the present application sequentially uses a centralized feeding mechanism, a melt extrusion mechanism, a mold forming mechanism, an internal cooling control mechanism and a traction and rolling mechanism to obtain a high puncture-resistant polyethylene geomembrane through five-layer co-extrusion blow molding.

[0026] Optionally, the first feeding assembly includes a first silo, a first quantitative feeder and a first hopper; the second feeding assembly includes a second silo, a second quantitative feeder and a second hopper; the third feeding assembly includes a third silo, a third quantitative feeder and a third hopper; the fourth feeding assembly includes a fourth silo, a fourth quantitative feeder and a fourth hopper; the fifth feeding assembly includes a fifth silo, a fifth quantitative feeder and a fifth hopper, and the first hopper, the second hopper, the third hopper, the fourth hopper and the fifth hopper are respectively arranged below the first quantitative feeder, the second quantitative feeder, the third quantitative feeder, the fourth quantitative feeder and the fifth quantitative feeder.

[0027] Specifically, the first silo is used to store modified linear low-density polyethylene resin, the second silo is used to store metallocene high-density polyethylene resin, the third silo is used to store medium-density polyethylene resin; the fourth silo is used to store linear low-density polyethylene resin, and the fifth silo is used to store double-resistant black masterbatch.

[0028] Specifically, the first quantitative feeder, the second quantitative feeder, the third quantitative feeder, the fourth quantitative feeder, and the fifth quantitative feeder extract raw materials from the corresponding silos according to the formula ratio and mix them fully, and then feed the mixed raw materials to the corresponding first hopper, the second hopper, the third hopper, the fourth hopper, and the fifth hopper.

[0029] Optionally, the melt extrusion mechanism includes a first screw melt extruder, a second screw melt extruder, a third screw melt extruder, a fourth screw melt extruder, and a fifth screw melt extruder, and the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder are respectively arranged below the first hopper, the second hopper, the third hopper, the fourth hopper, and the fifth hopper.

[0030] Specifically, the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder heat and melt the mixed raw materials fed from the first hopper, the second hopper, the third hopper, the fourth hopper, and the fifth hopper, respectively, and then extrude them into the mold molding mechanism.

[0031] Optionally, the mold molding mechanism includes a connecting pipe assembly, a fluid distributor, a five-layer molding mold and an A-frame; the connecting pipe assembly includes a first connecting pipe, a second connecting pipe, a third connecting pipe, a fourth connecting pipe and a fifth connecting pipe; the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe and the fifth connecting pipe respectively connect the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, the fifth screw melt extruder and the fluid distributor, and the fluid distributor is connected to the five-layer molding mold.

[0032] Specifically, a flowing melt is formed in a five-layer molding die and extruded through the five-layer molding die.

[0033] Specifically, a guide tube is arranged on the herringbone frame.

[0034] Optionally, the internal cooling control mechanism includes an air inlet fan, an air outlet fan, a width probe, an air inlet duct and an air outlet duct; the air inlet duct connects the air inlet fan and the five-layer forming mold, and the air outlet duct connects the air outlet fan and the five-layer forming mold; the traction and rolling mechanism includes a first traction machine, a cutting knife assembly, an upper guide roller, a film unfolding frame, a lower guide roller, a second traction machine, a film storage frame, a third traction machine and a friction rolling machine in sequence, and the cutting knife assembly includes a cutting knife and a cutting knife bracket; the five-layer forming mold includes a mold body, an air inlet and an air outlet, and a flow channel is provided inside the mold body, and the flow channel includes a first flow channel, a second flow channel, a third flow channel, a fourth flow channel and a fifth flow channel, and the first flow channel, the second flow channel, the third flow channel, the fourth flow channel and the fifth flow channel are respectively connected to the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe and the fifth connecting pipe.

[0035] Specifically, the five-layer forming mold collects the raw materials transported by the flow distribution, and extrude the geomembrane bubbles from the top of the mold, and the herringbone frame transports the extruded and cooled geomembrane bubbles upward and stably to the first traction machine.

[0036] Specifically, a five-layer film structure of an upper film, a first middle film, an inner film, a second middle film, and a lower film is formed through a five-layer molding die.

[0037] Specifically, the width probe is used to control the width of the geomembrane bubble.

[0038] According to another aspect of the present application, a production process of the above-mentioned high puncture-resistant polyethylene geomembrane is also provided, comprising the following steps:

[0039] S1 The first quantitative feeder, the second quantitative feeder, the third quantitative feeder, the fourth quantitative feeder, and the fifth quantitative feeder extract raw materials from the first silo, the second silo, the third silo, the fourth silo, and the fifth silo in proportion and mix them fully, and enter the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder through the first hopper, the second hopper, the third hopper, the fourth hopper, and the fifth hopper respectively;

[0040] S2: The first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder extrude the molten raw materials into the flow distribution through the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe, and the fifth connecting pipe, respectively, and transport them to the five-layer molding die to form a flowing melt, and the flowing melt is extruded through the five-layer molding die to obtain a cylindrical film bubble;

[0041] S3 lifts the cylindrical film bubble to the first traction machine, and the cylindrical film bubble forms a closed cylindrical cavity between the five-layer forming mold and the first traction machine; the air inlet fan injects air into the cylindrical cavity, and the air outlet fan discharges the air in the cylindrical cavity, and the air inlet fan and the air outlet fan are controlled according to the transverse draft ratio of 1: (1.2-1.4) to form a cylindrical cavity with a stable diameter;

[0042] The first traction machine S4 controls the traction speed according to the longitudinal stretching ratio of 1: (1.2~1.4) to form a cylindrical cavity with stable thickness. The cylindrical cavity is cut by the cutting knife assembly and unfolded by the film unfolding rack to form a geomembrane with stable width and stable thickness. After being pulled by the second traction machine, the film storage rack and the third traction machine, the friction rolling machine cuts it into rolls to obtain a high puncture-resistant polyethylene geomembrane.

[0043] Optionally, in S2, the aspect ratio of the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder is 35:1, the feeding section temperature is 175-185°C, the compression section temperature is 195-205°C, and the metering section temperature is 185-195°C; the diameter D1 of the first screw melt extruder is 120mm, the diameter D2 of the second screw melt extruder is 150mm, the diameter D3 of the third screw melt extruder is 180mm, the diameter D4 of the fourth screw melt extruder is 150mm, and the diameter D5 of the fifth screw melt extruder is 120mm.

[0044] Specifically, in S2, the extrusion ratios of the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder are 10%, 20%, 40%, 20%, and 10%, respectively.

[0045] Specifically, in S2, the extrusion ratios of the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder are 15%, 15%, 40%, 15%, and 15%, respectively.

[0046] Specifically, in S2, the extrusion ratios of the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder are 20%, 10%, 40%, 10%, and 20%, respectively.

[0047] Specifically, in S2, the extrusion ratios of the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder are 10%, 10%, 60%, 10%, and 10%, respectively.

[0048] Specifically, the extrusion ratio of the third screw melt extruder is greater than the extrusion ratios of the first screw melt extruder, the second screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder.

[0049] Specifically, the present application sets specific limits on the temperature. If the temperature is too high, the decomposition of the dual-resistance black masterbatch will be accelerated, the antioxidant properties of the geomembrane will be reduced, and the service life of the geomembrane will be greatly reduced.

[0050] Specifically, the present application makes specific restrictions on the steps and process parameters of the production process of high puncture-resistant polyethylene geomembrane, so that the obtained polyethylene geomembrane has good environmental stress cracking resistance and tearing resistance on the basis of excellent puncture resistance, and can adapt to harsh environment anti-seepage projects. It solves the problem of puncture damage to the geomembrane caused by the presence of many sharp-angled gravel in the compacted soil layer of the anti-seepage project, sharp-angled gravel in the gravel drainage layer, sharp objects in the backfill garbage, etc., and greatly improves the safety factor of the integrity of the geomembrane.

[0051] The beneficial effects of this application include but are not limited to:

[0052] 1. According to a highly puncture-resistant polyethylene geomembrane of the present application, the present application sequentially arranges an upper membrane, a first middle membrane, an inner membrane, a second middle membrane and a lower membrane from top to bottom to form a polyethylene geomembrane with a symmetrical five-layer membrane structure centered on the inner membrane, and specifically defines the components of each layer and the proportional relationship between the components, thereby simultaneously improving the puncture resistance and environmental stress cracking resistance of the polyethylene geomembrane to meet the needs of anti-seepage projects in harsh environments.

[0053] 2. According to a high puncture-resistant polyethylene geomembrane of the present application, in the upper and lower films, the modified linear low-density polyethylene resin is toughened and strengthened, and then acts together with the double-resistant black masterbatch, so that the upper and lower films have high stiffness, high tensile strength and high puncture resistance, and excellent flexibility and environmental stress cracking resistance; the first middle film and the second middle film adopt medium-density polyethylene resin, metallocene high-density polyethylene and double-resistant black masterbatch. The metallocene high-density polyethylene has high rigidity and high tensile modulus, and excellent puncture resistance, but its environmental stress cracking resistance The performance is poor, and it works together with a specific proportion of medium-density polyethylene resin and double-resistant black masterbatch to make it have good environmental stress cracking resistance and tearing resistance on the basis of excellent puncture resistance; the inner layer membrane adopts medium-density polyethylene resin, linear low-density polyethylene resin and double-resistant black masterbatch to improve the flexibility of the geomembrane while taking into account the rigidity requirements of the geomembrane. This application adopts a symmetrical five-layer membrane structure to work together, so that the geomembrane has good environmental stress cracking resistance and tearing resistance on the basis of excellent puncture resistance, and can adapt to harsh environment anti-seepage projects.

[0054] 3. According to a highly puncture-resistant polyethylene geomembrane of the present application, a modified linear low-density polyethylene resin is obtained by modifying the linear low-density polyethylene used in the present application, and its strength and toughness are improved, and it works together with the dual-resistant black masterbatch to ensure the puncture resistance, antioxidant performance and environmental stress cracking resistance of the geomembrane; on the one hand, a specific proportion of modified nano-silica and nano-titanium dioxide, and maleic anhydride grafted polyethylene work synergistically to improve its mechanical properties and toughness; on the other hand, the modified nano-silica effectively improves the dispersibility and compatibility of the nano-silica, further enhancing the modification effect.

[0055] 4. According to a production device of a high puncture-resistant polyethylene geomembrane of the present application, a five-layer co-extrusion blow molding process is adopted. The device is reasonably designed, can be compatible with the components and structure of the high puncture-resistant polyethylene geomembrane, and is conducive to improving production efficiency.

[0056] 5. According to the production process of a highly puncture-resistant polyethylene geomembrane of the present application, specific limitations are made on the steps and process parameters of the production process of the highly puncture-resistant polyethylene geomembrane, so that the obtained polyethylene geomembrane has good environmental stress cracking resistance and tearing resistance on the basis of excellent puncture resistance, and can adapt to anti-seepage projects in harsh environments. It solves the problem of puncture damage to the geomembrane caused by the presence of many sharp-angled gravel in the compacted soil layer of the anti-seepage project, sharp-angled gravel in the gravel drainage layer, sharp objects in the backfill garbage, etc., and greatly improves the safety factor of the integrity of the geomembrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0058] Figure 1 It is a schematic diagram of the cross-sectional structure of a production device for a high-puncture-resistant polyethylene geomembrane involved in an embodiment of the present application.

[0059] Figure 2 This is a schematic diagram of the cross-sectional structure of a five-layer molding mold involved in an embodiment of the present application.

[0060] Figure 3 This is a schematic diagram of the cross-sectional structure of the high puncture-resistant polyethylene geomembrane involved in an embodiment of the present application.

[0061] List of parts and reference numerals:

[0062] 1. First screw melt extruder; 2. First quantitative feeder; 3. First hopper; 4. Second screw melt extruder; 5. Second quantitative feeder; 6. Second hopper; 7. Third screw melt extruder; 8. Third quantitative feeder; 9. Third hopper; 10. Fourth screw melt extruder; 11. Fourth quantitative feeder; 12. Fourth hopper; 13. Fifth screw melt extruder; 14. Fifth quantitative feeder; 15. Fifth hopper; 16 fluid distribution; 17. Five-layer molding die; 18. Film bubble; 19. Herringbone frame; 20. Guide tube; 21. First tractor; 22. Slicer bracket; 23. Slicer; 24. Upper guide roller; 25. Film spreading frame; 26. Lower guide roller; 27. First Second traction machine; 28. Film storage rack; 29. ​​Third traction machine; 30. Friction rolling machine; 31. Fifth silo; 32. Fourth silo; 33. Third silo; 34. Second silo; 35. First silo; 36. First connecting pipe; 37. Second connecting pipe; 38. Third connecting pipe; 39. Fourth connecting pipe; 40. Fifth connecting pipe; 41. First flow channel; 42. Second flow channel; 43. Third flow channel; 44. Fourth flow channel; 45. Fifth flow channel; 46. Flowing melt; 47. Air inlet; 48. Width probe; 49. Air outlet; 50. Air inlet; 51. Air outlet; 52. Upper film; 53. First middle film; 54. Inner film; 55. Second middle film; 56. Lower film. DETAILED DESCRIPTION

[0063] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0064] Unless otherwise specified, the raw materials in the examples and comparative examples of the present application were purchased through commercial channels.

[0065] Unless otherwise specified, the methods used in the examples and comparative examples of the present application are conventional methods in the prior art.

[0066] Example 1

[0067] Preparation method of modified linear low-density polyethylene resin:

[0068] S01: 5 parts of modified nano silicon dioxide, 5 parts of nano titanium dioxide, 2 parts of maleic anhydride grafted polyethylene, 0.5 parts of antioxidant, and 0.05 parts of ultraviolet absorber are mixed uniformly to obtain a premix;

[0069] S02: adding the premix to 80 parts of linear low-density polyethylene resin and extruding the mixture using a twin-screw extruder at a temperature of 180°C;

[0070] S03 is cooled and granulated to obtain a modified linear low-density polyethylene resin.

[0071] Preparation method of high puncture resistance polyethylene geomembrane:

[0072] S1 The first quantitative feeder extracts 90 parts of modified linear low-density polyethylene resin and 2 parts of double-anti-black masterbatch from the first silo and the fifth silo respectively, mixes them thoroughly, and adds them to the first screw melt extruder through the first hopper. The length-to-diameter ratio of the first screw melt extruder is 35:1, and the diameter D=120mm. The feeding section temperature of the first screw melt extruder is 175°C, the compression section temperature is 195°C, and the metering section temperature is 185°C;

[0073] The second quantitative feeder extracts 40 parts of medium-density polyethylene resin, 35 parts of metallocene high-density polyethylene resin and 2 parts of double-anti-black masterbatch from the third silo, the second silo and the fifth silo respectively, and mixes them thoroughly, and adds them to the second screw melt extruder through the second hopper. The second screw melt extruder has a length-to-diameter ratio of 35:1 and a diameter of D=150 mm. The feeding section temperature of the second screw melt extruder is 175°C, the compression section temperature is 195°C, and the metering section temperature is 185°C;

[0074] The third quantitative feeder extracts 60 parts of medium-density polyethylene resin, 15 parts of linear low-density polyethylene resin and 2 parts of double-resistance black masterbatch from the third silo, the fourth silo and the fifth silo respectively, mixes them thoroughly, and adds them into the third screw melt extruder through the third hopper. The length-to-diameter ratio of the third screw melt extruder is 35:1, the diameter D=180mm, the feeding section temperature of the third screw melt extruder is 175°C, the compression section temperature is 195°C, and the metering section temperature is 185°C;

[0075] The fourth quantitative feeder extracts 40 parts of medium-density polyethylene resin, 35 parts of metallocene high-density polyethylene resin and 2 parts of double-resistance black masterbatch from the third silo, the second silo and the fifth silo respectively, mixes them thoroughly, and adds them into the fourth screw melt extruder through the fourth hopper. The fourth screw melt extruder has a length-to-diameter ratio of 35:1 and a diameter of D=150 mm. The feeding section temperature of the fourth screw melt extruder is 175°C, the compression section temperature is 195°C, and the metering section temperature is 185°C.

[0076] The fifth quantitative feeder extracts 90 parts of modified linear low-density polyethylene resin and 2 parts of double-resistance black masterbatch from the first silo and the fifth silo respectively, mixes them thoroughly, and adds them into the fifth screw melt extruder through the fifth hopper. The aspect ratio of the fifth screw melt extruder is 35:1, the diameter D=120mm, the feeding section temperature of the fifth screw melt extruder is 175°C, the compression section temperature is 195°C, and the metering section temperature is 185°C;

[0077] S2: the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder and the fifth screw melt extruder extrude the molten raw materials in the proportion of 20%, 10%, 40%, 10% and 20% respectively, and enter the flow distribution flow through the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe and the fifth connecting pipe respectively, and are transported to the five-layer molding die to form a flowing melt, and the flowing melt is extruded through the five-layer molding die to obtain a cylindrical film bubble;

[0078] S3 lifts the cylindrical film bubble to the first traction machine, and the cylindrical film bubble forms a closed cylindrical cavity between the five-layer forming mold and the first traction machine; the air inlet fan injects air into the cylindrical cavity, and the air outlet fan discharges the air in the cylindrical cavity. The air inlet fan and the air outlet fan are controlled according to the transverse draft ratio of 1:1.2 to form a cylindrical cavity with a stable diameter;

[0079] The first traction machine S4 controls the traction speed according to the longitudinal stretching ratio of 1:1.2 to form a cylindrical cavity with stable thickness. The cylindrical cavity is cut by the cutting knife assembly and unfolded by the film unfolding rack to form a geomembrane with stable width and thickness. After being pulled by the second traction machine, the film storage rack and the third traction machine, the friction rolling machine cuts it into rolls to obtain a high puncture-resistant polyethylene geomembrane.

[0080] Example 2

[0081] Preparation method of modified linear low-density polyethylene resin:

[0082] S01: 15 parts of modified nano silicon dioxide, 10 parts of nano titanium dioxide, 8 parts of maleic anhydride grafted polyethylene, 1.5 parts of antioxidant, and 0.1 parts of ultraviolet absorber are mixed uniformly to obtain a premix;

[0083] S02: adding the premix to 100 parts of linear low-density polyethylene resin, and extruding the mixture using a twin-screw extruder at a temperature of 220°C;

[0084] S03 is cooled and granulated to obtain a modified linear low-density polyethylene resin.

[0085] Preparation method of high puncture resistance polyethylene geomembrane:

[0086] S1 The first quantitative feeder extracts 100 parts of modified linear low-density polyethylene resin and 10 parts of double-anti-black masterbatch from the first silo and the fifth silo respectively, mixes them thoroughly, and adds them into the first screw melt extruder through the first hopper. The length-to-diameter ratio of the first screw melt extruder is 35:1, and the diameter D=120mm. The feeding section temperature of the first screw melt extruder is 185°C, the compression section temperature is 205°C, and the metering section temperature is 195°C;

[0087] The second quantitative feeder extracts 60 parts of medium-density polyethylene resin, 55 parts of metallocene high-density polyethylene resin and 10 parts of double-anti-black masterbatch from the third silo, the second silo and the fifth silo respectively, mixes them thoroughly, and adds them into the second screw melt extruder through the second hopper. The second screw melt extruder has a length-to-diameter ratio of 35:1 and a diameter of D=150 mm. The feeding section temperature of the second screw melt extruder is 185°C, the compression section temperature is 205°C, and the metering section temperature is 195°C;

[0088] The third quantitative feeder extracts 80 parts of medium-density polyethylene resin, 35 parts of linear low-density polyethylene resin and 10 parts of double-resistance black masterbatch from the third silo, the fourth silo and the fifth silo respectively, mixes them thoroughly, and adds them into the third screw melt extruder through the third hopper. The length-diameter ratio of the third screw melt extruder is 35:1, the diameter D=180mm, the feeding section temperature of the third screw melt extruder is 185°C, the compression section temperature is 205°C, and the metering section temperature is 195°C;

[0089] The fourth quantitative feeder extracts 60 parts of medium-density polyethylene resin, 55 parts of metallocene high-density polyethylene resin and 10 parts of double-anti-black masterbatch from the third silo, the second silo and the fifth silo respectively, mixes them thoroughly, and adds them into the fourth screw melt extruder through the fourth hopper. The fourth screw melt extruder has a length-to-diameter ratio of 35:1 and a diameter of D=150 mm. The feeding section temperature of the fourth screw melt extruder is 185°C, the compression section temperature is 205°C, and the metering section temperature is 195°C.

[0090] The fifth quantitative feeder extracts 100 parts of modified linear low-density polyethylene resin and 10 parts of double-resistance black masterbatch from the first silo and the fifth silo respectively, mixes them thoroughly, and adds them into the fifth screw melt extruder through the fifth hopper. The aspect ratio of the fifth screw melt extruder is 35:1, the diameter D=120mm, the feeding section temperature of the fifth screw melt extruder is 185°C, the compression section temperature is 205°C, and the metering section temperature is 195°C;

[0091] S2: the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder and the fifth screw melt extruder extrude the molten raw materials in the proportion of 15%, 15%, 40%, 15% and 15% respectively, and enter the flow distribution through the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe and the fifth connecting pipe respectively, and are transported to the five-layer molding die to form a flowing melt, and the flowing melt is extruded through the five-layer molding die to obtain a cylindrical film bubble;

[0092] S3 lifts the cylindrical film bubble to the first traction machine, and the cylindrical film bubble forms a closed cylindrical cavity between the five-layer forming mold and the first traction machine; the air inlet fan injects air into the cylindrical cavity, and the air outlet fan discharges the air in the cylindrical cavity. The air inlet fan and the air outlet fan are controlled according to the transverse draft ratio of 1:1.4 to form a cylindrical cavity with a stable diameter;

[0093] The first traction machine S4 controls the traction speed according to the longitudinal stretching ratio of 1:1.4 to form a cylindrical cavity with stable thickness. The cylindrical cavity is cut by the cutting knife assembly and unfolded by the film unfolding rack to form a geomembrane with stable width and thickness. After being pulled by the second traction machine, the film storage rack and the third traction machine, the friction rolling machine cuts it into rolls to obtain a high puncture-resistant polyethylene geomembrane.

[0094] Example 3

[0095] Preparation method of modified linear low-density polyethylene resin:

[0096] S01: 10 parts of modified nano silicon dioxide, 5 parts of nano titanium dioxide, 5 parts of maleic anhydride grafted polyethylene, 1 part of antioxidant, and 0.1 part of ultraviolet absorber are mixed uniformly to obtain a premix;

[0097] S02: adding the premix to 90 parts of linear low-density polyethylene resin, and extruding the mixture using a twin-screw extruder at a temperature of 200°C;

[0098] S03 is cooled and granulated to obtain a modified linear low-density polyethylene resin.

[0099] Preparation method of high puncture resistance polyethylene geomembrane:

[0100] S1 The first quantitative feeder extracts 95 parts of modified linear low-density polyethylene resin and 5 parts of double-resistance black masterbatch from the first silo and the fifth silo respectively, mixes them thoroughly, and adds them into the first screw melt extruder through the first hopper. The length-to-diameter ratio of the first screw melt extruder is 35:1, and the diameter D=120mm. The feeding section temperature of the first screw melt extruder is 180°C, the compression section temperature is 200°C, and the metering section temperature is 190°C;

[0101] The second quantitative feeder extracts 50 parts of medium-density polyethylene resin, 45 parts of metallocene high-density polyethylene resin and 5 parts of double-antioxidant black masterbatch from the third silo, the second silo and the fifth silo respectively, mixes them thoroughly, and adds them into the second screw melt extruder through the second hopper. The second screw melt extruder has a length-to-diameter ratio of 35:1 and a diameter of D=150 mm. The feeding section temperature of the second screw melt extruder is 180°C, the compression section temperature is 200°C, and the metering section temperature is 190°C.

[0102] The third quantitative feeder extracts 70 parts of medium-density polyethylene resin, 25 parts of linear low-density polyethylene resin and 5 parts of double-resistance black masterbatch from the third silo, the fourth silo and the fifth silo respectively, mixes them thoroughly, and adds them into the third screw melt extruder through the third hopper. The length-diameter ratio of the third screw melt extruder is 35:1, the diameter D=180mm, the feeding section temperature of the third screw melt extruder is 180°C, the compression section temperature is 200°C, and the metering section temperature is 190°C;

[0103] The fourth quantitative feeder extracts 50 parts of medium-density polyethylene resin, 45 parts of metallocene high-density polyethylene resin and 5 parts of double-resistance black masterbatch from the third silo, the second silo and the fifth silo respectively, mixes them thoroughly, and adds them into the fourth screw melt extruder through the fourth hopper. The fourth screw melt extruder has a length-to-diameter ratio of 35:1 and a diameter of D=150 mm. The feeding section temperature of the fourth screw melt extruder is 180°C, the compression section temperature is 200°C, and the metering section temperature is 190°C.

[0104] The fifth quantitative feeder extracts 95 parts of modified linear low-density polyethylene resin and 5 parts of double-resistance black masterbatch from the first silo and the fifth silo respectively, mixes them thoroughly, and adds them into the fifth screw melt extruder through the fifth hopper. The aspect ratio of the fifth screw melt extruder is 35:1, the diameter D=120mm, the feeding section temperature of the fifth screw melt extruder is 180°C, the compression section temperature is 200°C, and the metering section temperature is 190°C;

[0105] S2: the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder and the fifth screw melt extruder extrude the molten raw materials in the proportion of 10%, 20%, 40%, 20% and 10% respectively, and enter the flow distribution through the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe and the fifth connecting pipe respectively, and are transported to the five-layer molding die to form a flowing melt, and the flowing melt is extruded through the five-layer molding die to obtain a cylindrical film bubble;

[0106] S3 lifts the cylindrical film bubble to the first traction machine, and the cylindrical film bubble forms a closed cylindrical cavity between the five-layer forming mold and the first traction machine; the air inlet fan injects air into the cylindrical cavity, and the air outlet fan discharges the air in the cylindrical cavity. The air inlet fan and the air outlet fan are controlled according to the transverse draft ratio of 1:1.3 to form a cylindrical cavity with a stable diameter;

[0107] The first traction machine S4 controls the traction speed according to the longitudinal stretching ratio of 1:1.3 to form a cylindrical cavity with stable thickness. The cylindrical cavity is cut by the cutting knife assembly and unfolded by the film unfolding rack to form a geomembrane with stable width and thickness. After being pulled by the second traction machine, the film storage rack and the third traction machine, the friction rolling machine cuts it into rolls to obtain a high puncture-resistant polyethylene geomembrane.

[0108] Example 4

[0109] The difference between Example 4 and Example 3 is that the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder and the fifth screw melt extruder extrude the molten raw material in a ratio of 10%, 10%, 60%, 10% and 10%, respectively, and the rest are the same.

[0110] Example 5

[0111] The difference between Example 5 and Example 3 is that the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder and the fifth screw melt extruder extrude the molten raw material in the ratio of 20%, 20%, 20%, 20% and 20%, respectively, and the rest are the same.

[0112] Example 6

[0113] The difference between Example 6 and Example 3 is that the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder and the fifth screw melt extruder extrude the molten raw material in a ratio of 30%, 10%, 20%, 10% and 30% respectively, and the rest are the same.

[0114] Example 7

[0115] The difference between Example 7 and Example 3 is that the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder and the fifth screw melt extruder extrude the molten raw material in a ratio of 10%, 30%, 20%, 30% and 10%, respectively, and the rest are the same.

[0116] Example 8

[0117] The difference between Example 8 and Example 3 is that in S3 and S4, the transverse stretching ratio and the longitudinal stretching ratio are both 1.7, and the rest are the same.

[0118] Example 9

[0119] The difference between Example 9 and Example 3 is that in S3 and S4, the transverse stretching ratio and the longitudinal stretching ratio are both 1.1, and the rest are the same.

[0120] Example 10

[0121] The difference between Example 10 and Example 3 is that the feed section temperature of the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder is 200°C, the compression section temperature is 220°C, the metering section temperature is 210°C, and the rest are the same.

[0122] Embodiment 11

[0123] The difference between Example 11 and Example 3 is that the modified linear low-density polyethylene resin does not include modified nano-silica, and the rest is the same.

[0124] Example 12

[0125] The difference between Example 12 and Example 3 is that the modified nano-silica in the modified linear low-density polyethylene resin is not modified, and the rest is the same.

[0126] Example 13

[0127] The difference between Example 13 and Example 3 is that in the preparation method of modified nano-silica, the silane coupling agent is KH550, and the rest are the same.

[0128] Embodiment 14

[0129] The difference between Example 14 and Example 3 is that the modified linear low-density polyethylene resin does not include nano titanium dioxide, and the rest is the same.

[0130] Embodiment 15

[0131] The difference between Example 15 and Example 3 is that the modified linear low-density polyethylene resin does not include maleic anhydride polyethylene, and the rest is the same.

[0132] Comparative Example 1

[0133] The difference between Comparative Example 1 and Example 3 is that the upper film, the first middle film, the inner film, the second middle film and the lower film all include 95 parts of modified linear low-density polyethylene resin and 5 parts of double-resistant black masterbatch, and the rest are the same.

[0134] Comparative Example 2

[0135] The difference between Comparative Example 2 and Example 3 is that the upper film, the first middle film, the inner film, the second middle film and the lower film all include 50 parts of medium-density polyethylene resin, 45 parts of metallocene high-density polyethylene resin and 5 parts of double-anti-black masterbatch, and the rest are the same.

[0136] Comparative Example 3

[0137] The difference between Comparative Example 3 and Example 3 is that the upper film, the first middle film, the inner film, the second middle film and the lower film all include 70 parts of medium-density polyethylene resin, 25 parts of linear low-density polyethylene resin and 5 parts of double-resistant black masterbatch, and the rest are the same.

[0138] Comparative Example 4

[0139] The difference between Comparative Example 4 and Example 3 is that linear low-density polyethylene resin is used instead of modified linear low-density polyethylene resin, and the rest are the same.

[0140] Experimental Example 1

[0141] The polyethylene geomembrane prepared by the above method was tested for tensile properties, puncture resistance, environmental stress cracking resistance and oxidation resistance in the longitudinal and transverse directions. The test results are shown in Table 1.

[0142] Table 1 Performance test results

[0143]

[0144]

[0145] It can be seen from Table 1 that the polyethylene geomembrane provided in the present application has excellent puncture resistance and environmental stress cracking resistance, and can adapt to anti-seepage projects in harsh environments.

[0146] Depend on Figure 1 to Figure 3 It can be seen that the production device of high puncture-resistant polyethylene geomembrane provided in the present application sequentially passes through a centralized feeding mechanism, a melt extrusion mechanism, a mold forming mechanism, an internal cooling control mechanism and a traction and rolling mechanism, and obtains a high puncture-resistant polyethylene geomembrane by five-layer co-extrusion blow molding.

[0147] As an embodiment, the first feeding assembly includes a first silo 35, a first quantitative feeder 2 and a first hopper 3; the second feeding assembly includes a second silo 34, a second quantitative feeder 5 and a second hopper 6; the third feeding assembly includes a third silo 33, a third quantitative feeder 8 and a third hopper 9; the fourth feeding assembly includes a fourth silo 32, a fourth quantitative feeder 11 and a fourth hopper 12; the fifth feeding assembly includes a fifth silo 31, a fifth quantitative feeder 14 and a fifth hopper 15, and the first hopper 3, the second hopper 6, the third hopper 9, the fourth hopper 12 and the fifth hopper 15 are respectively arranged below the first quantitative feeder 2, the second quantitative feeder 5, the third quantitative feeder 8, the fourth quantitative feeder 11 and the fifth quantitative feeder 14.

[0148] Specifically, the first silo 35 is used to store modified linear low-density polyethylene resin, the second silo 34 is used to store metallocene high-density polyethylene resin, and the third silo 33 is used to store medium-density polyethylene resin; the fourth silo 32 is used to store linear low-density polyethylene resin, and the fifth silo 31 is used to store dual-resistance black masterbatch.

[0149] Specifically, the first quantitative feeder 2, the second quantitative feeder 5, the third quantitative feeder 8, the fourth quantitative feeder 11, and the fifth quantitative feeder 14 extract raw materials from the corresponding silos according to the formula ratio and mix them fully, and then feed them to the corresponding first hopper 3, the second hopper 6, the third hopper 9, the fourth hopper 12, and the fifth hopper 15 after mixing.

[0150] As an embodiment, the melt extrusion mechanism includes a first screw melt extruder 1, a second screw melt extruder 4, a third screw melt extruder 7, a fourth screw melt extruder 10, and a fifth screw melt extruder 13. The first screw melt extruder 1, the second screw melt extruder 4, the third screw melt extruder 7, the fourth screw melt extruder 10, and the fifth screw melt extruder 13 are respectively arranged below the first hopper 3, the second hopper 6, the third hopper 9, the fourth hopper 12, and the fifth hopper 15.

[0151] Specifically, the first screw melt extruder 1, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder heat and melt the mixed raw materials fed into the first hopper 3, the second hopper 6, the third hopper 9, the fourth hopper 12, and the fifth hopper 15, respectively, and then extrude them into the mold molding mechanism.

[0152] As an embodiment, the mold molding mechanism includes a connecting pipe assembly, a fluid distributor 16, a five-layer molding mold 17 and an A-frame 19; the connecting pipe assembly includes a first connecting pipe 36, a second connecting pipe 37, a third connecting pipe 38, a fourth connecting pipe 39 and a fifth connecting pipe 40; the first connecting pipe 36, the second connecting pipe 37, the third connecting pipe 38, the fourth connecting pipe 39 and the fifth connecting pipe 10 respectively connect the first screw melt extruder 1, the second screw melt extruder 4, the third screw melt extruder 7, the fourth screw melt extruder 10, the fifth screw melt extruder 13 with the fluid distributor 16, and the fluid distributor 16 is connected to the five-layer molding mold 17.

[0153] Specifically, a fluid melt 46 is formed in the five-layer molding die 17 and extruded through the five-layer molding die 17 .

[0154] Specifically, a guide tube 20 is provided on the herringbone frame 19 .

[0155] As an implementation mode, the internal cooling control mechanism includes an air inlet 50, an air outlet 51, a width probe 48, an air inlet pipe and an air outlet pipe; the air inlet pipe connects the air inlet 50 with the five-layer forming mold 17, and the air outlet pipe connects the air outlet 51 with the five-layer forming mold 17; the traction and rolling mechanism includes a first traction machine 21, a slitting knife assembly, an upper guide roller 24, a film unfolding frame 25, a lower guide roller 26, a second traction machine 27, a film storage frame 28, a third traction machine 29 and a friction rolling machine 30 in sequence, and the slitting knife assembly includes a slitting knife 23 and the dissecting knife bracket 22; the five-layer molding mold 17 includes a mold body, an air inlet 47 and an air outlet 49, and a flow channel is arranged inside the mold body, and the flow channel includes a first flow channel 41, a second flow channel 42, a third flow channel 43, a fourth flow channel 44 and a fifth flow channel 45, and the first flow channel 41, the second flow channel 42, the third flow channel 43, the fourth flow channel 44 and the fifth flow channel 45 are respectively connected to the first connecting pipe 36, the second connecting pipe 37, the third connecting pipe 38, the fourth connecting pipe 39 and the fifth connecting pipe 40.

[0156] Specifically, the five-layer forming die 17 collects the raw materials transported by the flow divider 16 and extrude the geomembrane bubble 18 from the top of the die, and the herringbone frame 19 transports the extruded and cooled geomembrane bubble 18 upward and stably to the first tractor 21 .

[0157] Specifically, a five-layer film structure of an upper film 52 , a first middle film 53 , an inner film 54 , a second middle film 55 , and a lower film 56 is formed through the five-layer molding die 17 .

[0158] Specifically, the width probe 48 is used to control the width of the geomembrane bubble 18 .

[0159] The above is only the embodiment of the present application, and the protection scope of the present application is not limited by these specific embodiments, but is determined by the claims of the present application. For those skilled in the art, the present application can have various changes and variations. Any modification, equivalent replacement, improvement, etc. made within the technical ideas and principles of the present application should be included in the protection scope of the present application.

Claims

1. A high puncture resistance polyethylene geomembrane, characterized in that: From top to bottom, it includes an upper film, a first middle film, an inner film, a second middle film and a lower film; in terms of weight, the upper film and the lower film each include 90-100 parts of a modified linear low-density polyethylene resin and 2-10 parts of a double-anti-black masterbatch; the first middle film and the second middle film each include 40-60 parts of a medium-density polyethylene resin, 35-55 parts of a metallocene high-density polyethylene resin and 2-10 parts of a double-anti-black masterbatch; the inner film includes 60-80 parts of a medium-density polyethylene resin, 15-35 parts of a linear low-density polyethylene resin and 2-10 parts of a double-anti-black masterbatch.

2. The high puncture resistance polyethylene geomembrane according to claim 1, characterized in that: Calculated by weight, the modified linear low-density polyethylene resin includes 80 to 100 parts of linear low-density polyethylene, 5 to 15 parts of modified nano-silicon dioxide, 5 to 10 parts of nano-titanium dioxide, 2 to 8 parts of maleic anhydride grafted polyethylene, 0.5 to 1.5 parts of antioxidant, and 0.05 to 0.1 parts of ultraviolet absorber; the modified nano-silicon dioxide is prepared by modification with a silane coupling agent.

3. The high puncture resistance polyethylene geomembrane according to claim 2, characterized in that: The preparation method of the modified nano silicon dioxide comprises the following steps: (1) dispersing nano-silicon dioxide in ethanol to obtain a nano-silicon dioxide dispersion; (2) adding a silane coupling agent to the nano-silicon dioxide dispersion, heating and stirring; (3) Centrifugation and vacuum drying to obtain modified nano-silica.

4. The production device of the high puncture resistance polyethylene geomembrane according to any one of claims 1 to 3, characterized in that: It includes a centralized feeding mechanism, a melt extrusion mechanism, a mold forming mechanism, an internal cooling control mechanism and a traction rolling mechanism in sequence; the centralized feeding mechanism includes a first feeding component, a second feeding component, a third feeding component, a fourth feeding component and a fifth feeding component.

5. The high puncture resistance polyethylene geomembrane production device according to claim 4 is characterized in that: The first feeding assembly includes a first silo, a first quantitative feeder and a first hopper; the second feeding assembly includes a second silo, a second quantitative feeder and a second hopper; the third feeding assembly includes a third silo, a third quantitative feeder and a third hopper; the fourth feeding assembly includes a fourth silo, a fourth quantitative feeder and a fourth hopper; the fifth feeding assembly includes a fifth silo, a fifth quantitative feeder and a fifth hopper, and the first hopper, the second hopper, the third hopper, the fourth hopper and the fifth hopper are respectively arranged below the first quantitative feeder, the second quantitative feeder, the third quantitative feeder, the fourth quantitative feeder and the fifth quantitative feeder.

6. The high puncture resistance polyethylene geomembrane production device according to claim 5 is characterized in that: The melt extrusion mechanism includes a first screw melt extruder, a second screw melt extruder, a third screw melt extruder, a fourth screw melt extruder, and a fifth screw melt extruder. The first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder are respectively arranged below the first hopper, the second hopper, the third hopper, the fourth hopper, and the fifth hopper.

7. The high puncture resistance polyethylene geomembrane production device according to claim 4 is characterized in that: The mold forming mechanism includes a connecting pipe assembly, a flow divider, a five-layer forming mold and an A-frame; the connecting pipe assembly includes a first connecting pipe, a second connecting pipe, a third connecting pipe, a fourth connecting pipe and a fifth connecting pipe; the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe and the fifth connecting pipe respectively connect the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, the fifth screw melt extruder and the flow divider, and the flow divider is connected to the five-layer forming mold.

8. The high puncture resistance polyethylene geomembrane production device according to claim 4 is characterized in that: The internal cooling control mechanism includes an air inlet fan, an air outlet fan, a width probe, an air inlet duct and an air outlet duct; the air inlet duct connects the air inlet fan and the five-layer forming mold, and the air outlet duct connects the air outlet fan and the five-layer forming mold; the traction and rolling mechanism includes a first traction machine, a cutting knife assembly, an upper guide roller, a film unfolding frame, a lower guide roller, a second traction machine, a film storage frame, a third traction machine and a friction rolling machine in sequence, and the cutting knife assembly includes a cutting knife and a cutting knife bracket; the five-layer forming mold includes a mold body, an air inlet and an air outlet, and a flow channel is provided inside the mold body, and the flow channel includes a first flow channel, a second flow channel, a third flow channel, a fourth flow channel and a fifth flow channel, and the first flow channel, the second flow channel, the third flow channel, the fourth flow channel and the fifth flow channel are respectively connected to the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe and the fifth connecting pipe.

9. The production process of high puncture-resistant polyethylene geomembrane according to any one of claims 1 to 3, characterized in that: The following steps are involved: S1 The first quantitative feeder, the second quantitative feeder, the third quantitative feeder, the fourth quantitative feeder, and the fifth quantitative feeder extract raw materials from the first silo, the second silo, the third silo, the fourth silo, and the fifth silo in proportion and mix them fully, and enter the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder through the first hopper, the second hopper, the third hopper, the fourth hopper, and the fifth hopper respectively; S2: The first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder extrude the molten raw materials into the flow distribution through the first connecting pipe, the second connecting pipe, the third connecting pipe, the fourth connecting pipe, and the fifth connecting pipe, respectively, and transport them to the five-layer molding die to form a flowing melt, and the flowing melt is extruded through the five-layer molding die to obtain a cylindrical film bubble; S3 lifts the cylindrical film bubble to the first traction machine, and the cylindrical film bubble forms a closed cylindrical cavity between the five-layer forming mold and the first traction machine; the air inlet fan injects air into the cylindrical cavity, and the air outlet fan discharges the air in the cylindrical cavity, and the air inlet fan and the air outlet fan are controlled according to the transverse draft ratio of 1: (1.2-1.4) to form a cylindrical cavity with a stable diameter; The first traction machine S4 controls the traction speed according to the longitudinal stretching ratio of 1: (1.2~1.4) to form a cylindrical cavity with stable thickness. The cylindrical cavity is cut by the cutting knife assembly and unfolded by the film unfolding rack to form a geomembrane with stable width and stable thickness. After being pulled by the second traction machine, the film storage rack and the third traction machine, the friction rolling machine cuts it into rolls to obtain a high puncture-resistant polyethylene geomembrane.

10. The production process of high puncture-resistant polyethylene geomembrane according to claim 9, characterized in that: In S2, the aspect ratio of the first screw melt extruder, the second screw melt extruder, the third screw melt extruder, the fourth screw melt extruder, and the fifth screw melt extruder is 35:1, the temperature of the feeding section is 175-185°C, the temperature of the compression section is 195-205°C, and the temperature of the metering section is 185-195°C; the diameter D1 of the first screw melt extruder is 120mm, the diameter D2 of the second screw melt extruder is 150mm, the diameter D3 of the third screw melt extruder is 180mm, the diameter D4 of the fourth screw melt extruder is 150mm, and the diameter D5 of the fifth screw melt extruder is 120mm.

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