High-wear-resistance silicon core pipe and preparation method thereof

Abstract

The invention relates to the technical field of silicon core pipes, and provides a high-wear-resistance silicon core pipe and a preparation method thereof. The high-wear-resistance silicon core pipe comprises an outer layer and an inner layer, and the outer layer is prepared from, by weight, 90-110 parts of high-density polyethylene, 10-15 parts of ethylene acrylic acid copolymer, 1-2 parts of antioxidant, 10-20 parts of polyacrylonitrile carbon fiber, 1-3 parts of flame retardant and 1-3 parts of lubricant; the inner layer is prepared from the following raw materials in parts by weight: 8 to 10 parts of polydimethylsiloxane, 70 to 90 parts of high-density polyethylene, 10 to 15 parts of ethylene-acrylic acid copolymer, 1 to 2 parts of antioxidant and 1 to 3 parts of flame retardant; the lubricant is prepared from 2-fluoro-5-(trifluoromethyl) aniline and / or N-propenyl pyrrolidone. According to the technical scheme, the problem of low wear resistance of the silicon core pipe in the prior art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of silicon core tubes, and in particular to a highly wear-resistant silicon core tube and a preparation method thereof. Background Art

[0002] HDPE silicon core pipe is a kind of pipe composed of high-density polyethylene outer layer and silicon core. It is widely used in underground communication line protection, urban infrastructure construction, traffic tunnel communication and other fields due to its advantages such as light weight, easy handling and installation, and low cost. With the development of communication technology, higher requirements are put forward for pipeline materials. Since there are usually sand, gravel, soil and other particulate matter in the underground environment, if the pipeline material does not have good wear resistance, it is easy to be worn and damaged, thus affecting the stability and reliability of the communication line. Therefore, ensuring that the HDPE silicon core pipe has good wear resistance is crucial for the continuous operation of underground communications. Summary of the invention

[0003] The invention provides a highly wear-resistant silicon core tube and a preparation method thereof, which solves the problem of low wear resistance of the silicon core tube in the related art.

[0004] The technical scheme of the present invention is as follows: The present invention provides a highly wear-resistant silicon core tube, comprising an outer layer and an inner layer, wherein the outer layer comprises the following raw materials in parts by weight: 90-110 parts of high-density polyethylene, 10-15 parts of ethylene acrylic acid copolymer, 1-2 parts of antioxidant, 10-20 parts of polyacrylonitrile carbon fiber, 1-3 parts of flame retardant, and 1-3 parts of lubricant; The inner layer comprises the following raw materials in parts by weight: 8-10 parts of polydimethylsiloxane, 70-90 parts of high-density polyethylene, 10-15 parts of ethylene acrylic acid copolymer, 1-2 parts of antioxidant, and 1-3 parts of flame retardant; The lubricant includes 2-fluoro-5-trifluoromethylaniline and / or N-propenylpyrrolidone.

[0005] As a further technical solution, the lubricant consists of 2-fluoro-5-trifluoromethylaniline and N-propenylpyrrolidone.

[0006] As a further technical solution, the mass ratio of the 2-fluoro-5-trifluoromethylaniline to N-propenylpyrrolidone is 3-5:1.

[0007] As a further technical solution, the mass ratio of the 2-fluoro-5-trifluoromethylaniline to N-propenylpyrrolidone is 4:1.

[0008] As a further technical solution, the antioxidant includes one or both of antioxidant 1010 and antioxidant 168 .

[0009] As a further technical solution, the flame retardant includes one or two of aluminum oxide and bromide-based flame retardants.

[0010] As a further technical solution, the brominated flame retardant includes one or two of decabromodiphenylethane and bromotriazine.

[0011] As a further technical solution, the polyacrylonitrile carbon fiber includes one or more of powdered polyacrylonitrile carbon fiber, chopped polyacrylonitrile carbon fiber, and continuous polyacrylonitrile carbon fiber.

[0012] As a further technical solution, the polyacrylonitrile carbon fiber is chopped carbon fiber.

[0013] The present invention also provides a method for preparing a highly wear-resistant silicon core tube, comprising the following steps: S1, mixing the outer layer raw materials uniformly to obtain an outer layer mixture; S2, mixing the inner layer raw materials uniformly to obtain an inner layer mixture; S3, after the outer layer mixture and the inner layer mixture are heated and melted respectively, they are extruded and compounded simultaneously, and after shaping, a silicon core tube is obtained.

[0014] As a further technical solution, the outer layer raw materials are mixed at a temperature of 120-130° C. and a mixing time of 60-90 min.

[0015] As a further technical solution, the inner layer raw materials are mixed at a temperature of 105-120° C. and a mixing time of 40-50 min.

[0016] The working principle and beneficial effects of the present invention are: In the present invention, 2-fluoro-5-trifluoromethylaniline and / or N-propylene pyrrolidone are used as lubricants, wherein the aromatic ring part of 2-fluoro-5-trifluoromethylaniline makes the molecule have good stability and rigidity, which helps to reduce the friction coefficient while enhancing the mechanical strength of the silicon core tube, and can increase the wear resistance of the molecule to a certain extent. The trifluoromethyl group can reduce the polarity of the molecule and increase the hydrophobicity of the molecule, so that they reduce the friction when in contact with other materials, thereby improving the wear resistance and increasing the maximum traction load of the silicon core tube. The vinyl functional group in N-propylene pyrrolidone can be used to chemically bond with the surface of the HDPE material, which helps to enhance the adhesion between the coating and the pipe surface, improve the wear resistance and mechanical strength, and the pyrrolidone functional group can improve the hydrophilicity of the coating, form a hydrophilic film, improve the smoothness of the pipe surface, reduce the friction coefficient, thereby improving the wear resistance and increasing the maximum traction load. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] In the following examples and comparative examples: Powdered polyacrylonitrile carbon fiber: diameter 7μm, length 0.01~2mm, manufacturer is Hangzhou Gaoke Composite Materials Co., Ltd.; Chopped polyacrylonitrile carbon fiber: length 0.01~50mm, manufacturer is Hangzhou Gaoke Composite Materials Co., Ltd.; Continuous polyacrylonitrile carbon fiber: model is nce, manufacturer is Jiangsu Nongchaoer Composite Materials Co., Ltd.; Ethylene acrylic acid copolymer: solid content 36%, manufacturer is Shanghai Kundu Industrial Co., Ltd.; High-density polyethylene: model number is P4406C, the manufacturer is Suzhou Jedamin Plastic Raw Materials Co., Ltd.; Polydimethylsiloxane: model number is ST-30, content is 30%, manufacturer is Suzhou Jingyu Biotechnology Co., Ltd.; Silicone oil: Model is AP150, manufacturer is Nanjing Sisbo Silicone Co., Ltd.

[0019] Example 1 S1, weigh 90 parts of high-density polyethylene, 10 parts of ethylene acrylic acid copolymer, 1 part of antioxidant 1010, 10 parts of powdered polyacrylonitrile carbon fiber, 1 part of aluminum oxide, and 1 part of 2-fluoro-5-trifluoromethylaniline, heat to 120°C, stir for 90 minutes, mix evenly, and obtain an outer layer mixture; S2, weigh 8 parts of polydimethylsiloxane, 70 parts of high-density polyethylene, 10 parts of ethylene acrylic acid copolymer, 1 part of antioxidant 1010, and 1 part of aluminum oxide, heat to 105°C, stir for 50 minutes, mix evenly, and obtain an inner layer mixture; S3, after the outer layer mixture and the inner layer mixture are heated and melted respectively, they are extruded and compounded simultaneously, and after shaping, a silicon core tube is obtained.

[0020] Example 2 S1. Weigh 100 parts of high-density polyethylene, 12 parts of ethylene acrylic acid copolymer, 1.5 parts of antioxidant 1010, 15 parts of chopped polyacrylonitrile carbon fiber, 2 parts of decabromodiphenylethane, and 2.4 parts of 2-fluoro-5-trifluoromethylaniline, heat to 125° C., stir for 75 minutes, mix well, and obtain an outer layer mixture; S2, weigh 9 parts of polydimethylsiloxane, 80 parts of high-density polyethylene, 12 parts of ethylene acrylic acid copolymer, 1.5 parts of antioxidant 1010, and 2 parts of decabromodiphenylethane, heat to 115°C, stir for 45 minutes, mix well, and obtain an inner layer mixture; S3, after the outer layer mixture and the inner layer mixture are heated and melted respectively, they are extruded and compounded simultaneously, and after shaping, a silicon core tube is obtained.

[0021] Example 3 S1. Weigh 110 parts of high-density polyethylene, 15 parts of ethylene acrylic acid copolymer, 2 parts of antioxidant 168, 20 parts of continuous polyacrylonitrile carbon fiber, 3 parts of bromotriazine, and 3 parts of 2-fluoro-5-trifluoromethylaniline, heat to 130°C, stir for 60 minutes, mix well, and obtain an outer layer mixture; S2, weigh 10 parts of polydimethylsiloxane, 90 parts of high-density polyethylene, 15 parts of ethylene acrylic acid copolymer, 2 parts of antioxidant 1010, and 3 parts of bromotriazine, heat to 120°C, stir for 40 minutes, mix evenly, and obtain an inner layer mixture; S3, after the outer layer mixture and the inner layer mixture are heated and melted respectively, they are extruded and compounded simultaneously, and after shaping, a silicon core tube is obtained.

[0022] Example 4 Compared with Example 2, Example 4 is different in that 2-fluoro-5-trifluoromethylaniline is replaced by an equal amount of N-propenylpyrrolidone.

[0023] Example 5 Compared with Example 2, Example 5 is different in that 2.4 parts of 2-fluoro-5-trifluoromethylaniline are replaced by 1.6 parts of 2-fluoro-5-trifluoromethylaniline and 0.8 parts of N-propenylpyrrolidone.

[0024] Example 6 Compared with Example 2, Example 6 is different in that 2.4 parts of 2-fluoro-5-trifluoromethylaniline are replaced by 1.8 parts of 2-fluoro-5-trifluoromethylaniline and 0.6 parts of N-propenylpyrrolidone.

[0025] Example 7 Compared with Example 2, Example 7 is different in that 2.4 parts of 2-fluoro-5-trifluoromethylaniline are replaced by 1.92 parts of 2-fluoro-5-trifluoromethylaniline and 0.48 parts of N-propenylpyrrolidone.

[0026] Example 8 Compared with Example 2, Example 8 is different in that 2.4 parts of 2-fluoro-5-trifluoromethylaniline are replaced by 2.0 parts of 2-fluoro-5-trifluoromethylaniline and 0.4 parts of N-propenylpyrrolidone.

[0027] Example 9 Compared with Example 2, Example 9 is different in that 2.4 parts of 2-fluoro-5-trifluoromethylaniline are replaced by 2.1 parts of 2-fluoro-5-trifluoromethylaniline and 0.3 parts of N-propenylpyrrolidone.

[0028] Comparative Example 1 Compared with Example 2, the difference in Comparative Example 1 is that 2-fluoro-5-trifluoromethylaniline is replaced by an equal amount of silicone oil.

[0029] The highly wear-resistant silicon core tube prepared in Examples 1 to 9 and Comparative Example 1 was tested according to the following method: 1. Outer layer wear: According to the test method specified in GB / T 5478-2008 "Plastic Rolling Wear Test Method", the outer layer wear of the test sample is tested.

[0030] 2. Maximum traction load: According to the test method specified in YD / T 841.4-2016 "Plastic pipes for underground communication pipelines Part 4: Silicon core pipes", the maximum traction load of the test sample is tested.

[0031] Table 1 Performance test results of silicon core tubes prepared in Examples 1 to 9 and Comparative Example 1

[0032] Compared with Comparative Example 1, Examples 1 to 3 add 2-fluoro-5-trifluoromethylaniline, and Example 4 adds N-propenyl pyrrolidone. As a result, the outer layer wear amount of Examples 1 to 3 is less than that of Comparative Example 1, and the maximum traction load is greater than that of Comparative Example 1, indicating that the addition of 2-fluoro-5-trifluoromethylaniline or N-propenyl pyrrolidone can improve the wear resistance and maximum traction load of the silicon core tube.

[0033] Compared with Example 2, Examples 5 to 9 simultaneously added 2-fluoro-5-trifluoromethylaniline and N-propenylpyrrolidone. As a result, the outer layer wear amount of Examples 5 to 9 was less than that of Example 2, and the maximum traction load was greater than that of Example 2, indicating that 2-fluoro-5-trifluoromethylaniline and N-propenylpyrrolidone played a synergistic role and could further improve the wear resistance of the silicon core tube.

[0034] Compared with Example 5, Examples 6 to 9 added 2-fluoro-5-trifluoromethylaniline and N-propenylpyrrolidone in different proportions. As a result, the outer layer wear amount of Examples 6 to 8 was less than that of Examples 5 and 9, and the maximum traction load was greater than that of Examples 5 and 9, indicating that when the mass ratio of 2-fluoro-5-trifluoromethylaniline and N-propenylpyrrolidone is 3 to 5:1, and the preferred mass ratio is 4:1, the wear resistance of the silicon core tube is best.

[0035] Referring to the test method specified in the standard GB / T 24456-2009 "High-density polyethylene silicon core tube", the appearance, drop hammer impact resistance, cold bending radius, chemical medium corrosion resistance, hydraulic resistance, thermal stress cracking resistance, and hydrocarbon resistance of Examples 1 to 9 were tested, and the test results are as follows: Appearance: The color is uniform, the inner and outer surfaces are flat, uniform and smooth, without defects such as collapse, pits, holes, tear marks and impurity pits, the cross-section is bright, without bubbles or cracks, the inner wall of the silicon core tube is tightly sintered without detachment, all meeting the requirements.

[0036] Drop hammer impact resistance: At the specified temperature (normal temperature 23℃, low temperature -20℃), at a height of 2m, a 15.3kg hammer impacted 10 specimens, and none of the 10 specimens showed cracking, meeting the qualification standards.

[0037] Cold bending radius: No cracking, cracking or obvious stress whitening.

[0038] Resistance to chemical corrosion: The samples were immersed in 5% NaCl, 40% H2SO4 and 40% NaOH solutions for 24 hours respectively, and there was no obvious fading or corrosion.

[0039] Hydraulic resistance: Under the conditions of temperature 20℃ and water pressure 2.0MPa, maintained for 15min, there are no visible cracks on the samples.

[0040] Resistance to thermal stress cracking: 168h, failure rate is 0.

[0041] Inner wall friction coefficient: static ≤0.25, all samples passed.

[0042] Therefore, the silicon core tubes of Examples 1 to 9 of the present invention all meet the relevant requirements of the standard GB / T 24456-2009 "High-density polyethylene silicon core tube".

[0043] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A highly wear-resistant silicon core tube, It is characterized in that It comprises an outer layer and an inner layer, wherein the outer layer comprises the following raw materials in parts by weight: 90-110 parts of high-density polyethylene, 10-15 parts of ethylene acrylic acid copolymer, 1-2 parts of antioxidant, 10-20 parts of polyacrylonitrile carbon fiber, 1-3 parts of flame retardant, and 1-3 parts of lubricant; The inner layer comprises the following raw materials in parts by weight: 8-10 parts of polydimethylsiloxane, 70-90 parts of high-density polyethylene, 10-15 parts of ethylene acrylic acid copolymer, 1-2 parts of antioxidant, and 1-3 parts of flame retardant; the lubricant comprises 2-fluoro-5-trifluoromethylaniline and / or N-acrylpyrrolidone.

2. A highly wear-resistant silicon core tube according to claim 1, It is characterized in that The lubricant consists of 2-fluoro-5-trifluoromethylaniline and N-propenylpyrrolidone.

3. A highly wear-resistant silicon core tube according to claim 2, It is characterized in that The mass ratio of the 2-fluoro-5-trifluoromethylaniline to N-propenylpyrrolidone is 3-5:

1.

4. A highly wear-resistant silicon core tube according to claim 1, It is characterized in that The antioxidant includes one or both of antioxidant 1010 and antioxidant 168 .

5. A highly wear-resistant silicon core tube according to claim 1, It is characterized in that The flame retardant includes one or both of aluminum oxide and bromine-based flame retardant.

6. A highly wear-resistant silicon core tube according to claim 5, It is characterized in that The brominated flame retardant includes one or two of decabromodiphenylethane and bromotriazine.

7. A highly wear-resistant silicon core tube according to claim 1, It is characterized in that The polyacrylonitrile carbon fiber includes one or more of powdered polyacrylonitrile carbon fiber, chopped polyacrylonitrile carbon fiber, and continuous polyacrylonitrile carbon fiber.

8. A method for preparing a highly wear-resistant silicon core tube according to any one of claims 1 to 7, It is characterized in that The following steps are involved: S1, mixing the outer layer raw materials uniformly to obtain an outer layer mixture; S2, mixing the inner layer raw materials uniformly to obtain an inner layer mixture; S3, after the outer layer mixture and the inner layer mixture are heated and melted respectively, they are extruded and compounded simultaneously, and after shaping, a silicon core tube is obtained.

9. A method for preparing a highly wear-resistant silicon core tube according to claim 8, It is characterized in that The outer layer raw materials are mixed at a temperature of 120-130° C. and a mixing time of 60-90 min.

10. The method for preparing a highly wear-resistant silicon core tube according to claim 8, It is characterized in that The inner layer raw materials are mixed at a temperature of 105-120° C. and a mixing time of 40-50 min.

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