Buried arch-shaped winding pipe composite material and winding pipe
By adding high-strength fibers and specific inorganic fillers to polyethylene gas buried pipelines, the problem of insufficient bearing capacity of polyethylene pipelines in complex terrain and corrosive environments is solved, and high pressure strength and brittleness resistance are improved.
Patent Information
- Application Number
- CN202510936913.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-08
- Publication Date
- 2025-10-10
AI Technical Summary
Existing polyethylene buried gas pipelines have insufficient load-bearing capacity in complex terrains and are prone to cracking due to pressure and external forces. They are also prone to corrosion due to long-term exposure to soil environments, affecting their sealing and strength.
High-density polyethylene is used as the base material, and linear low-density polyethylene, glass fiber, polylactic acid fiber, ethylene-butene polymer, ethylene-octene polymer and inorganic fillers such as calcium carbonate and silicon carbide in a specific proportion are added. The polyethylene structural wall tube is prepared by stirring, melting and extrusion to enhance its pressure bearing strength and brittleness resistance.
It improves the pressure-bearing strength and brittleness resistance of polyethylene structural wall pipes, slows down the crack growth rate, and enhances the durability and sealing of pipelines in complex terrain and corrosive environments.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of polymer materials, in particular to a buried arch-shaped winding pipe composite material and a winding pipe. Background Art A buried gas pipeline is a pipeline system used to transport natural gas, liquefied petroleum gas and other gases. It is buried underground to safely transport gas to various user points.
[0002] Traditional buried gas pipelines typically utilize high-strength steel pipes, which can withstand significant pressure and external forces. Welded or threaded connections provide excellent sealing properties, effectively preventing gas leaks. However, steel pipes are heavy, making transportation, installation, and construction more difficult. Furthermore, prolonged exposure to soil and humid environments can lead to corrosion, which can reduce the strength and sealing properties of the pipes and increase the risk of leaks. Therefore, plastic pipes are gradually becoming an alternative to steel pipes.
[0003] Polyethylene wall pipe is a specially structured polyethylene pipe with excellent strength and rigidity, capable of withstanding certain pressures and loads. However, when used in underground applications, due to the complexities of underground installations, buried polyethylene pipes often need to withstand significant pressure loads to meet long-term pipeline requirements. However, the load-bearing capacity of existing polyethylene pipes is relatively low, leaving room for improvement. Summary of the Invention
[0004] In order to further improve the pressure-bearing strength of a buried arch-shaped wound pipe composite material and a wound pipe, the present application provides a buried arch-shaped wound pipe composite material and a wound pipe.
[0005] In a first aspect, the present application provides a buried arch-shaped wound pipe composite material, which adopts the following technical solution: A buried arch-shaped wound pipe composite material comprises the following components in parts by mass: 80-100 parts of high-density polyethylene; 10-20 parts of linear low-density polyethylene; 5-8 parts of fiber, composed of glass fiber and polylactic acid fiber in a mass ratio of (4-7): (1-2); 6-9 parts of an anti-cracking agent, composed of ethylene-butene polymer and ethylene-octene polymer in a mass ratio of (3-4): (3-5); 10-15 parts of inorganic filler; 4-5 parts of anti-aging agent; 2-5 parts of coupling agent; 2-4 parts of dispersant.
[0006] By adopting the technical scheme, the polyethylene structural wall pipe for buried use is prepared by taking high-density polyethylene as a base material. Because the molecular chain arrangement is regular and has no branch chain, the prepared polyethylene structural wall pipe has high hardness. By adding a small amount of linear low-density polyethylene, which has a short and small comonomer branch chain on the main chain and has stronger impact resistance than high-density polyethylene, the flexibility of the polyethylene wall pipe is improved. The elastic deformation capacity of the polyethylene wall pipe and the surrounding soil form a good stress structure, and the wall pipe is not prone to rupture and cracking due to complex terrain changes.
[0007] By adding glass fibers and polylactic acid fibers with high strength and rigidity, the mechanical properties of polyethylene can be effectively enhanced, so that the prepared polyethylene structural wall pipe has high pressure-bearing strength and can withstand high-intensity load under low pressure. By adding ethylene-butene polymer and ethylene-octene polymer, the rate of slow growth of material cracks is slowed down, the brittleness resistance of the polyethylene wall pipe is improved, and the polyethylene wall pipe can still maintain good shape under high load-bearing pressure and is not prone to cracking. Even in a terrain environment containing many sharp stones and sand, the polyethylene pipe is not prone to cracking due to local strong external force. At the same time, the glass fibers and polylactic acid fibers are beneficial to further connecting the ethylene-butene polymer and the ethylene-octene polymer, so that the hardness of the pipe is not too high, the flexibility of the pipe is not reduced, and the bending capacity is weakened. When subjected to external force or internal pressure increases, the pipe is prone to rupture.
[0008] Preferably, the inorganic filler includes one or more of calcium carbonate, silicon carbide, silicon nitride, and calcium sulfate whisker.
[0009] By adopting the above technical scheme, the above one or more substances are used as inorganic fillers to fill the voids of polyethylene and increase the compactness of the material. This can improve the hardness, strength, and wear resistance of polyethylene and improve the mechanical properties of the material.
[0010] Preferably, the inorganic filler is composed of calcium carbonate and silicon carbide in a mass ratio of (2-5):(8-10).
[0011] By adopting the above technical scheme, the specific proportion of calcium carbonate and silicon carbide as inorganic fillers is beneficial to improving the hardness and strength of polyethylene and improving the mechanical properties of polyethylene. At the same time, it does not easily affect the flexibility and brittleness resistance of polyethylene.
[0012] Preferably, the particle size of the calcium carbonate is 50-800 μm, and the particle size of the silicon carbide is 40-50 nm.
[0013] By adopting the above technical solution, micron-sized calcium carbonate and nano-sized silicon carbide are used as inorganic fillers to fully fill the pores of polyethylene, increase the density and firmness of the material, improve the hardness of the polyethylene pipe, and improve the mechanical properties of polyethylene; at the same time, it is not easy to affect the flexibility and brittleness of polyethylene.
[0014] Preferably, the anti-aging agent is carbon black.
[0015] By adopting the above technical solution and using carbon black as an antioxidant, the polyethylene can be protected, stabilized, and strengthened, which is beneficial to improving the durability and reliability of the polyethylene structural wall pipe.
[0016] Preferably, the coupling agent includes one or more of silane coupling agent KH-540, silane coupling agent KH-550, silane coupling agent KH-560, and silane coupling agent KH-570.
[0017] By adopting the above technical solution and using the above one or more substances as coupling agents, the inorganic filler can have better fluidity between polyethylene molecules, so that the inorganic filler can be evenly dispersed in the wall tube, further improving the pressure bearing strength of the wall tube.
[0018] Preferably, the dispersant is PE520 dispersant.
[0019] By adopting the above technical solution and using PE520 dispersant as the dispersant, the distribution of particles in the components can be adjusted, the fluidity of polyethylene can be improved, and the quality of the polyethylene structural wall pipe for ground use can be improved.
[0020] In a second aspect, the present application provides a method for preparing a buried arch-shaped wound pipe composite material, which adopts the following technical solution: A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: High-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are mixed uniformly to obtain a premix; Step 2, adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and mixing them uniformly to obtain a mixture; Step 3, adding the above mixture into a twin-screw, heating and melting, extruding, cooling and granulating to obtain a polyethylene structure wall pipe for underground use.
[0021] By adopting the above technical solution and following the above steps to prepare the buried polyethylene structure wall pipe, the prepared polyethylene structure wall pipe has a higher pressure bearing capacity.
[0022] In a third aspect, the present application provides a winding pipe, which adopts the following technical solution: A wound pipe made from the buried arch-shaped wound pipe composite material comprises a polyethylene structural wall pipe made from the buried arch-shaped wound pipe composite material and a through pipe wound around the polyethylene structural wall pipe.
[0023] By adopting the above technical solution, the polyethylene structural wall pipe made from the buried arch-shaped winding pipe composite material has a higher pressure-bearing strength, so that the winding pipe also has a higher pressure-bearing strength.
[0024] In summary, this application has the following beneficial effects: 1. By adding high-strength and rigid glass fiber and polylactic acid fiber, the mechanical properties of polyethylene can be effectively enhanced, giving the resulting polyethylene structural wall pipe a high compressive strength, allowing it to withstand high-intensity loads at low temperatures. The addition of ethylene-butene polymer and ethylene-octene polymer helps slow the rate of slow-growth cracks in the material and improves the polyethylene wall pipe's brittleness. This allows the polyethylene wall pipe to maintain its shape under high loads and resist cracking. Even in terrain with a high concentration of sharp rocks and gravel, the polyethylene pipe is less susceptible to cracking due to localized strong external forces. Furthermore, glass fiber and polylactic acid fiber further connect the ethylene-butene polymer and ethylene-octene polymer, preventing them from becoming too hard, which would reduce the pipe's flexibility and bending capacity, making it susceptible to rupture when subjected to external forces or increased internal pressure.
[0025] 2. By using calcium carbonate and silicon carbide as inorganic fillers in a specific proportion, it is beneficial to increase the hardness and strength of polyethylene and improve the mechanical properties of polyethylene; at the same time, it is not easy to affect the flexibility of polyethylene. BRIEF DESCRIPTION OF THE DRAWINGS
[0026] Figure 1 This is a schematic diagram of the structure of a buried arch-shaped winding pipe.
[0027] In the figure, 1. Polyethylene structural wall pipe; 2. Through pipe. DETAILED DESCRIPTION
[0028] The present application is further described in detail below with reference to the embodiments.
[0029] The raw materials of the following examples and experimental examples are all commercially available, as follows: The CAS number of high-density polyethylene is 9002-88-4; The CAS number of linear low-density polyethylene is 88497-56-7; The CAS number of glass fiber is 65997-17-3; The CAS number of nano-silicon carbide is 409-21-2 The CAS number of carbon black is 1333-86-4; The CAS number of silane coupling agent KH-540 is 13822-56-5; Silicon nitride was purchased from Shanghai Pantian Powder Materials Co., Ltd. with a particle size of 20 nm; Silicon carbide was purchased from Shanghai Jiadeer Chemical Technology Co., Ltd. with a particle size of 20 nm, a particle size of 40 nm, and a particle size of 0.5-0.7 μm; calcium carbonate was purchased from Ningbo Beijiaer New Materials Co., Ltd. with a particle size of 50-800 nm and a particle size of 1-10 μm; Carbon fiber was purchased from Wuhan Jiyesheng Chemical Co., Ltd.; Ethylene-propylene polymer was purchased from Dongguan Shenghao Plastic Raw Materials Co., Ltd., model VERSIFY TM 3000; Polylactic acid fiber was purchased from Xi'an Qiyue Biotechnology Co., Ltd.; Ethylene-butene polymer was purchased from Suzhou Junjun Plastic Raw Materials Co., Ltd., brand DF640; Ethylene-octene polymer was purchased from Hongji Plastics Trading Company, Zhangmutou, Dongguan City, brand 8201; PE520 dispersant was purchased from Guangzhou Haocheng New Materials Co., Ltd.
[0030] Example 1 A buried arch-shaped spiral pipe composite material, consisting of the following components: 80kg high-density polyethylene; 10kg linear low-density polyethylene; 4kg glass fiber, 1kg polylactic acid fiber; 3kg ethylene-butene polymer, 3kg ethylene-octene polymer; 10kg inorganic filler; 4kg anti-aging agent; 2kg coupling agent; 2kg dispersant.
[0031] The inorganic filler is a mixture of 2 kg calcium carbonate and 8 kg silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0032] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0033] Example 2 A buried arch-shaped spiral pipe composite material, consisting of the following components: 100kg high-density polyethylene; 20kg linear low-density polyethylene; 7kg glass fiber, 2kg polylactic acid fiber; 4kg ethylene-butene polymer, 5kg ethylene-octene polymer; 15kg inorganic filler; 5kg anti-aging agent; 5kg coupling agent; 4kg dispersant.
[0034] The inorganic filler is a mixture of 5 kg calcium carbonate and 10 kg silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0035] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0036] Example 3 A buried arch-shaped spiral pipe composite material, consisting of the following components: 90kg high-density polyethylene; 15kg linear low-density polyethylene; 5.5kg glass fiber, 1.5kg polylactic acid fiber; 3.5kg ethylene-butene polymer, 4kg ethylene-octene polymer; 12.5kg inorganic filler; 4.4kg anti-aging agent; 3.5kg coupling agent; 3kg dispersant.
[0037] The inorganic filler is a mixture of 3.5 kg of calcium carbonate and 9 kg of silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0038] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0039] Example 4 A buried arch-shaped spiral pipe composite material, consisting of the following components: 90kg high-density polyethylene; 15kg linear low-density polyethylene; 5.5kg glass fiber, 1.5kg polylactic acid fiber; 3.5kg ethylene-butene polymer, 4kg ethylene-octene polymer; 12.5kg inorganic filler; 4.4kg anti-aging agent; 3.5kg coupling agent; 3kg dispersant.
[0040] The inorganic filler is a mixture of 2-5 kg of silicon nitride and 8-10 kg of silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0041] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0042] The difference from Example 3 is that the calcium carbonate is replaced by an equal amount of silicon nitride.
[0043] Example 5 A buried arch-shaped spiral pipe composite material, consisting of the following components: 90kg high-density polyethylene; 15kg linear low-density polyethylene; 5.5kg glass fiber, 1.5kg polylactic acid fiber; 3.5kg ethylene-butene polymer, 4kg ethylene-octene polymer; 12.5kg inorganic filler; 4.4kg anti-aging agent; 3.5kg coupling agent; 3kg dispersant.
[0044] The inorganic filler is a mixture of 2-5 kg of calcium carbonate and 8-10 kg of silicon nitride; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0045] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0046] The difference from Example 3 is that silicon carbide is replaced by equal amounts of silicon nitride.
[0047] Example 6 A buried arch-shaped spiral pipe composite material, consisting of the following components: 90kg high-density polyethylene; 15kg linear low-density polyethylene; 5.5kg glass fiber, 1.5kg polylactic acid fiber; 3.5kg ethylene-butene polymer, 4kg ethylene-octene polymer; 12.5kg inorganic filler; 4.4kg anti-aging agent; 3.5kg coupling agent; 3kg dispersant.
[0048] The inorganic filler is a mixture of 2-5 kg of calcium carbonate and 8-10 kg of silicon nitride; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0049] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0050] The difference from Example 3 is that the particle size of calcium carbonate is 1-10 μm.
[0051] Example 7 A buried arch-shaped spiral pipe composite material, consisting of the following components: 90kg high-density polyethylene; 15kg linear low-density polyethylene; 5.5kg glass fiber, 1.5kg polylactic acid fiber; 3.5kg ethylene-butene polymer, 4kg ethylene-octene polymer; 12.5kg inorganic filler; 4.4kg anti-aging agent; 3.5kg coupling agent; 3kg dispersant.
[0052] The inorganic filler is a mixture of 2-5 kg of calcium carbonate and 8-10 kg of silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0053] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0054] The difference from Example 3 is that the particle size of silicon carbide is 0.5-0.7 μm.
[0055] Comparative Example 1 A buried arch-shaped spiral pipe composite material, consisting of the following components: 90kg high-density polyethylene; 15kg linear low-density polyethylene; 5.5kg carbon fiber, 1.5kg polylactic acid fiber; 3.5kg ethylene-butene polymer, 4kg ethylene-octene polymer; 12.5kg inorganic filler; 4.4kg anti-aging agent; 3.5kg coupling agent; 3kg dispersant.
[0056] The inorganic filler is a mixture of 2-5 kg of calcium carbonate and 8-10 kg of silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0057] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3, take the above mixture into the double screw, melt at 220℃, rotate at 180r / min, extrude, cool and granulate to obtain the polyethylene structural wall pipe for buried use.
[0058] The difference from Example 3 is that the equal amount of carbon fibers respectively replace the glass fibers.
[0059] Comparative Example 2 A buried arch-shaped winding pipe composite material is composed of the following components by mass: High-density polyethylene 90 kg; linear low-density polyethylene 15 kg; glass fiber 5.5 kg, carbon fiber 1.5 kg; ethylene-butene polymer 3.5 kg, ethylene-octene polymer 4 kg; inorganic filler 12.5 kg; anti-aging agent 4.4 kg; coupling agent 3.5 kg; dispersing agent 3 kg.
[0060] Among them, the inorganic filler is mixed by 2-5 kg of calcium carbonate and 8-10 kg of silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersing agent is PE520 dispersing agent.
[0061] A preparation method of a buried arch-shaped winding pipe composite material, comprising the following steps: Step 1, take high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler, stir at a rotation speed of 50r / min for 20 minutes to obtain a premix; Step 2, add anti-aging agent, coupling agent, and dispersing agent to the premix, stir at a rotation speed of 50r / min for 20 minutes to obtain a mixture; Step 3, take the above mixture into the double screw, melt at 220℃, rotate at 180r / min, extrude, cool and granulate to obtain the polyethylene structural wall pipe for buried use.
[0062] The difference from Example 3 is that the equal amount of carbon fibers respectively replace the glass fibers.
[0063] Comparative Example 3 A buried arch-shaped winding pipe composite material is composed of the following components by mass: High-density polyethylene 90 kg; linear low-density polyethylene 15 kg; glass fiber 5.5 kg, poly lactic acid fiber 1.5 kg; ethylene-propylene polymer 3.5 kg, ethylene-octene polymer 4 kg; inorganic filler 12.5 kg; anti-aging agent 4.4 kg; coupling agent 3.5 kg; dispersing agent 3 kg.
[0064] Among them, the inorganic filler is mixed by 2-5 kg of calcium carbonate and 8-10 kg of silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersing agent is PE520 dispersing agent.
[0065] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; The above mixture is added into a twin-screw extruder, heated to 220°C for melting, rotated at 180 r / min, extruded, cooled and granulated to obtain a polyethylene structural wall pipe for underground use.
[0066] The difference from Example 3 is that the ethylene-propylene polymer is used in equal amounts to replace the ethylene-butene polymer.
[0067] Comparative Example 4 A buried arch-shaped spiral pipe composite material, consisting of the following components: 90kg high-density polyethylene; 15kg linear low-density polyethylene; 5.5kg glass fiber, 1.5kg polylactic acid fiber; 3.5kg ethylene-butene polymer, 4kg ethylene-propylene polymer; 12.5kg inorganic filler; 4.4kg anti-aging agent; 3.5kg coupling agent; 3kg dispersant.
[0068] The inorganic filler is a mixture of 2-5 kg of calcium carbonate and 8-10 kg of silicon carbide; the antioxidant is carbon black; the coupling agent is silane coupling agent KH-540; and the dispersant is PE520 dispersant.
[0069] A method for preparing a buried arch-shaped wound pipe composite material comprises the following steps: Step 1: high-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are stirred at a speed of 50 r / min for 20 minutes to obtain a premix; Step 2: adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and stirring at a speed of 50 r / min for 20 minutes to obtain a mixture; Step 3: add the above mixture into a twin-screw extruder, heat to 220°C for melting, rotate at 180 r / min, extrude, cool and granulate to obtain a polyethylene structural wall pipe for underground use.
[0070] The difference from Example 3 is that the ethylene-octene polymer is replaced by an equal amount of ethylene-propylene polymer.
[0071] Application Example 1 A winding tube, such as Figure 1As shown, it includes a polyethylene structural wall pipe 1 made of a wound pipe composite material in the shape of an underground arch and a through pipe 2 wound around the polyethylene structural wall pipe 1.
[0072] In this application example, the polyethylene structure wall tube 1 is the polyethylene structure wall tube 1 prepared in Example 1.
[0073] Experiment 1 Pipeline Stress Intensity A pipeline stress test device was used to perform pipeline stress testing to record the maximum pressure (MPa) that the pipeline could withstand without leakage. The buried pipeline stress detector was purchased from Beijing Zhongcheng Jiayi Technology Co., Ltd.
[0074] The above experimental test data are detailed in Table 1.
[0075] Experiment 2: Flexibility The pipe masterbatch prepared in the above embodiment and comparative example was tested for elongation at break according to GB / T 1040.1-2018, with a tensile rate of 20 mm / min.
[0076] The above experimental test data are detailed in Table 1.
[0077] Experiment 3 Slow growth crack rate The pipe masterbatches prepared in the above examples and comparative examples were injection molded into polyethylene-walled pipes with an outer diameter of 220 mm and a wall thickness of 5 mm. Four V-shaped notches with an angle of 60° and a depth of 1 mm were machined into the outer surface of the polyethylene-walled pipe along the axial direction. Each notch was spaced 90° apart along the circumference. The opened polyethylene-walled pipe was placed in an 80°C water tank under static pressure for testing, and the maximum time (h) for pipe failure was recorded.
[0078] The above experimental test data are detailed in Table 1.
[0079] Table 1 Comparison of the data in Example 3 and Comparative Examples 1-4 in Table 1 shows that Example 3, using high-density polyethylene and linear low-density polyethylene as substrates, with the addition of glass fiber, polylactic acid fiber, ethylene-butene polymer, and ethylene-octene polymer, produces a polyethylene structural wall tube having good compressive strength and a low crack growth rate. Comparative Examples 1-2, by replacing the glass fiber and polylactic acid fiber with equal amounts of carbon fiber, respectively, reduce the compressive strength of the polyethylene structural wall tubes produced. Comparative Examples 3-4, by replacing the ethylene-butene polymer and ethylene-octene polymer with equal amounts of ethylene-propylene polymer, respectively, increase the crack growth rate of the polyethylene structural wall tubes produced. Comparative Examples 1-4, by replacing the glass fiber, polylactic acid fiber, ethylene-butene polymer, and ethylene-octene polymer with equal amounts of carbon fiber and ethylene-propylene polymer, respectively, produce polyethylene structural wall tubes having good compressive strength while still maintaining good flexibility.
[0080] According to the data comparison of Example 3 and Examples 6-7 in Table 1, it can be seen that using calcium carbonate and silicon carbide of specific particle sizes as inorganic fillers is beneficial to increasing the hardness and strength of polyethylene and improving the mechanical properties of polyethylene; at the same time, it is not easy to affect the flexibility of polyethylene.
[0081] According to the data comparison of Example 3 and Examples 4-5 in Table 1, it can be seen that using calcium carbonate and silicon carbide as inorganic fillers in a specific ratio is beneficial to increasing the hardness and strength of polyethylene and improving the mechanical properties of polyethylene; at the same time, it is not easy to affect the flexibility of polyethylene.
[0082] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make non-creative modifications to the present embodiment as needed, but as long as they are within the scope of the claims of the present application, they are protected by the patent law.
Claims
1. A buried arch-shaped wound pipe composite material, characterized by: The composition includes the following parts by weight: 80-100 parts of high-density polyethylene; 10-20 parts of linear low-density polyethylene; 5-8 parts of fiber, composed of glass fiber and polylactic acid fiber in a mass ratio of (4-7): (1-2); 6-9 parts of an anti-cracking agent, composed of ethylene-butene polymer and ethylene-octene polymer in a mass ratio of (3-4): (3-5); 10-15 parts of inorganic filler; 4-5 parts of anti-aging agent; 2-5 parts of coupling agent; 2-4 parts of dispersant.
2. The buried arch-shaped wound pipe composite material according to claim 1, characterized in that: The inorganic filler includes one or more of calcium carbonate, silicon carbide, silicon nitride, and calcium sulfate whiskers.
3. The buried arch-shaped wound pipe composite material according to claim 2, characterized in that: The inorganic filler is composed of calcium carbonate and silicon carbide in a mass ratio of (2-5): (8-10).
4. The buried arch-shaped wound pipe composite material according to claim 3, characterized in that: The particle size of the calcium carbonate is 50-800 μm; the particle size of the silicon carbide is 40-50 nm.
5. The buried arch-shaped wound pipe composite material according to claim 1, characterized in that: The anti-aging agent is carbon black.
6. The buried arch-shaped wound pipe composite material according to claim 1, characterized in that: The coupling agent includes one or more of silane coupling agent KH-540, silane coupling agent KH-550, silane coupling agent KH-560, and silane coupling agent KH-570.
7. The buried arch-shaped wound pipe composite material according to claim 1, characterized in that: The dispersant is PE520 dispersant.
8. A method for preparing a buried arch-shaped wound pipe composite material according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1: High-density polyethylene, linear low-density polyethylene, fiber, anti-cracking agent, and inorganic filler are mixed uniformly to obtain a premix; Step 2, adding an anti-aging agent, a coupling agent, and a dispersant to the premix, and mixing them uniformly to obtain a mixture; Step 3, adding the above mixture into a twin-screw, heating and melting, extruding, cooling and granulating to obtain a polyethylene structure wall pipe for underground use.
9. A wound pipe made of the buried arch-shaped wound pipe composite material according to any one of claims 1 to 7, characterized in that: The invention comprises a polyethylene structural wall pipe (1) made of a buried arch-shaped winding pipe composite material and a through pipe (2) wound around the polyethylene structural wall pipe.
Citation Information
Patent Citations
Toughened modified high-density polyethylene material and preparation method thereof
CN108178862A