A polyethylene drip irrigation pipe for preventing crop scalding

Abstract

The invention relates to the technical field of irrigation pipes, and proposes a polyethylene drip irrigation pipe for preventing crops from being scalded, comprising a drip irrigation pipe body and a plurality of patch drippers embedded on the inner wall of the drip irrigation pipe body, the drip irrigation pipe body comprising an inner layer pipe and an outer layer pipe sequentially arranged from the inside to the outside, the raw materials of the inner layer pipe comprising the following components in parts by weight: 100 parts of polyethylene, 4.5-5.7 parts of carbon black, and 3-5 parts of masterbatch; the raw materials of the outer layer pipe comprising the following components in parts by weight: 100 parts of metallocene polyethylene, 3-5 parts of masterbatch, and 3-8 parts of PPA masterbatch. Through the above technical scheme, the problems of polyethylene drip irrigation pipes in the related art that they are easy to scald crops and have low hydrostatic strength are solved.

Description

Technical Field

[0001] The invention relates to the technical field of irrigation pipes, and in particular to a polyethylene drip irrigation pipe for preventing crops from being scalded. Background Art

[0002] Polyethylene drip irrigation pipe is a common pipe equipment for agricultural irrigation. It can save water, fertilizer and increase crop yield. It is made of polyethylene as the base material, with carbon black, masterbatch and other additives added. The addition of an appropriate amount of carbon black can mainly play the role of coloring, anti-ultraviolet and anti-aging. It is also due to the coloring effect of carbon black that the polyethylene drip irrigation pipe is black. As we all know, black is easy to absorb heat, which causes the water temperature in the polyethylene drip irrigation pipe to rise due to heat absorption when used outdoors. Especially in the hot summer, the rising water temperature will cause scalding to crops.

[0003] In addition, in order to meet the use requirements, the drip irrigation pipe must also have a certain anti-static hydraulic strength, which is reflected by two parameters: resistance to hydrostatic pressure and bursting pressure. However, the anti-static hydraulic strength of the existing polyethylene drip irrigation pipe needs to be improved. Summary of the invention

[0004] The invention provides a polyethylene drip irrigation pipe for preventing crops from being scalded, which solves the problem in the related art that the polyethylene drip irrigation pipe is easy to scald crops and has low hydrostatic pressure resistance.

[0005] The technical solution of the present invention is as follows:

[0006] A polyethylene drip irrigation pipe for preventing crops from being scalded comprises a drip irrigation pipe body and a plurality of patch drippers embedded on the inner wall of the drip irrigation pipe body, wherein the drip irrigation pipe body comprises an inner layer pipe and an outer layer pipe sequentially arranged from the inside to the outside.

[0007] The raw materials of the inner layer tube include the following components in parts by weight: 100 parts of polyethylene, 4.5-5.7 parts of carbon black, and 3-5 parts of masterbatch;

[0008] The raw materials of the outer layer tube include the following components in parts by weight: 100 parts of metallocene polyethylene, 3-5 parts of masterbatch, and 3-8 parts of PPA masterbatch.

[0009] As a further technical solution, the melt flow rate of the polyethylene at 190° C. and a load of 2.16 kg is less than 2 g / 10 min.

[0010] In the present invention, polyethylenes with different melt flow rates have different mechanical properties. When the melt flow rate of polyethylene at 190° C. and a load of 2.16 kg is less than 2 g / 10 min, the obtained drip irrigation pipe has higher anti-static hydraulic strength.

[0011] As a further technical solution, the polyethylene includes a first polyethylene and a second polyethylene having different melt flow rates.

[0012] The melt flow rate of the first polyethylene at 190° C. and 2.16 kg load is 0.2 g / 10 min to 0.5 g / 10 min,

[0013] The melt flow rate of the second polyethylene at 190° C. and 2.16 kg load is 1 g / 10 min to 1.5 g / 10 min.

[0014] The mass of the first polyethylene is less than the mass of the second polyethylene.

[0015] In the present invention, the first polyethylene and the second polyethylene having different melt flow rates cooperate with each other to further improve the hydrostatic strength of the drip irrigation pipe.

[0016] As a further technical solution, the mass ratio of the first polyethylene to the second polyethylene is 1:4 to 2:3.

[0017] In the present invention, when the mass of the first polyethylene is less than the mass of the second polyethylene, especially when the mass ratio of the first polyethylene to the second polyethylene is 1:4-2:3, the obtained drip irrigation pipe has a higher anti-static hydraulic strength.

[0018] As a further technical solution, the melt flow rate of the metallocene polyethylene at 190° C. and 2.16 kg load is 0.5-2.0 g / 10 min.

[0019] In the present invention, when the melt flow rate of the metallocene polyethylene in the outer layer tube is 0.5-2.0 g / 10 min at 190° C. and 2.16 kg load, the metallocene polyethylene and the polyethylene in the inner layer tube work synergistically to further improve the hydrostatic strength of the drip irrigation pipe.

[0020] As a further technical solution, the PPA masterbatch comprises the following components in parts by weight:

[0021] 40-60 parts of linear low-density polyethylene, 30-50 parts of ethylene-acrylic acid copolymer, 5-10 parts of antioxidant, and 2-4 parts of fluorine-containing polymer.

[0022] In the present invention, the fluorine-containing polymer is composed of a low surface energy fluorocarbon polymer, which is added to the matrix resin to lubricate the matrix resin and improve the surface quality of the product. The fluorine-containing polymer may be, for example, polyvinylidene fluoride, polyvinylidene fluoride-hexafluoroethylene, polyvinylidene fluoride-chlorotrifluoroethylene, preferably polyvinylidene fluoride.

[0023] In the present invention, the PPA masterbatch uses linear low-density polyethylene and ethylene-acrylic acid copolymer as carrier resins. On the one hand, the PPA masterbatch has good processing performance and improves the compatibility of the PPA masterbatch with the metallocene polyethylene matrix. On the other hand, the addition of the ethylene-acrylic acid copolymer also improves the dispersibility of the fluoropolymer, thereby promoting the effectiveness of the fluoropolymer in the PPA masterbatch, thereby further improving the hydrostatic strength of the drip irrigation pipe.

[0024] As a further technical solution, the mass content of acrylic acid in the ethylene-acrylic acid copolymer is 7.5% to 10%.

[0025] In the present invention, when the mass content of acrylic acid in the ethylene-acrylic acid copolymer is 7.5% to 10%, the dispersibility of the fluorine-containing polymer is better, and the hydrostatic strength of the drip irrigation pipe is further improved.

[0026] As a further technical solution, the PPA masterbatch also includes 1 to 2 parts of polyvinyl pyrrolidone.

[0027] In the present invention, the addition of polyvinyl pyrrolidone further improves the dispersion uniformity of the fluorine-containing polymer, thereby further improving the hydrostatic strength of the drip irrigation pipe. Polyvinyl pyrrolidone may be, for example, PVP-K30, PVP-K60, PVP-K90, preferably PVP-K30.

[0028] As a further technical solution, the preparation method of the PPA masterbatch includes the following steps: mixing the fluorine-containing polymer with linear low-density polyethylene, ethylene-acrylic acid copolymer, and an antioxidant, extruding and granulating the mixture, and drying the mixture to obtain the PPA masterbatch.

[0029] In the present invention, the fluorine-containing polymer is added in the form of first mixing with linear low-density polyethylene, ethylene-acrylic acid copolymer, antioxidant, etc. to prepare masterbatch by extrusion, and then adding the masterbatch into the metallocene polyethylene resin matrix, which further promotes the effect of the fluorine-containing polymer, not only improves the surface quality of the drip irrigation pipe, but also further improves the anti-static hydraulic strength of the drip irrigation pipe.

[0030] As a further technical solution, the inner diameter of the drip irrigation pipe body is 15.7-16.3 mm, preferably 16 mm; the wall thickness is 0.19-0.24 mm, preferably 0.2 mm; the drip hole spacing of the patch dripper is 285-315 mm, preferably 300 mm.

[0031] The working principle and beneficial effects of the present invention are:

[0032] In the present invention, the drip irrigation pipe body includes an inner layer pipe and an outer layer pipe which are sequentially arranged from the inside to the outside, and carbon black is only added to the inner layer pipe, which not only meets the requirement (2.25%±0.50%) for the carbon black content in the drip irrigation pipe in the standard of GB T 19812.3-2017 "Plastic Water-Saving Irrigation Equipment Part 3: Inlaid Drip Irrigation Pipe and Drip Irrigation Belt", but also avoids the problem of scalding crops due to the carbon black in the outer layer pipe causing the drip irrigation pipe to absorb heat. The outer layer pipe uses metallocene polyethylene as a matrix, which improves the anti-static hydraulic strength of the polyethylene drip irrigation pipe. DETAILED DESCRIPTION

[0033] 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.

[0034] In the following examples and comparative examples, the raw material information is as follows:

[0035] (1) The grades of polyethylene and their corresponding melt flow rates are:

[0036] Polyethylene LLDPE DFDA7042, melt flow rate (190℃, 2.16kg) is 2g / 10min;

[0037] The first polyethylene LLDPE BD20030BA, the melt flow rate (190 ° C, 2.16 kg) is 0.35 g / 10 min;

[0038] The second polyethylene LLDPE 2045G has a melt flow rate (190° C., 2.16 kg) of 1 g / 10 min.

[0039] (2) The grades of metallocene polyethylene and their corresponding melt flow rates are:

[0040] Metallocene polyethylene mLLDPE LL7835A, melt flow rate (190°C, 2.16kg) is 3.5g / 10min;

[0041] Metallocene polyethylene mLLDPE 2018MA, melt flow rate (190°C, 2.16kg) is 2g / 10min;

[0042] Metallocene polyethylene mLLDPE 2005MC, melt flow rate (190°C, 2.16kg) is 0.5g / 10min;

[0043] Metallocene polyethylene mLLDPE 2703MC, melt flow rate (190°C, 2.16kg) is 0.3g / 10min.

[0044] (3) The grades of ethylene-acrylic acid copolymers and the corresponding mass contents of acrylic acid are:

[0045] Ethylene-acrylic acid copolymer EAA 5200, mass content of acrylic acid: 15%;

[0046] Ethylene-acrylic acid copolymer EAA 5080, mass content of acrylic acid: 10%;

[0047] Ethylene-acrylic acid copolymer EAA 5020, mass content of acrylic acid: 7.5%;

[0048] Ethylene acrylic acid copolymer EAA 6000, mass content of acrylic acid: 6%.

[0049] (4) Carbon black is a pigment.

[0050] (5) The masterbatch is a silver-grey masterbatch.

[0051] (6) The PPA masterbatch model is PPA-1M, which was purchased from Shaoxing Shangyu Qimingxing Plastic New Material Co., Ltd.

[0052] (7) Linear low-density polyethylene grade is LLDPE 3470, density is 0.926 g / cm 3 , the melt flow rate (190℃, 2.16kg) is 25g / 10min.

[0053] (8) The fluorine-containing polymer is polyvinylidene fluoride, and its brand name is PVDF DS206.

[0054] (9) The polyvinyl pyrrolidone is PVP-K30.

[0055] In the following embodiments and comparative examples, the inner diameter of the polyethylene drip irrigation pipe is 16 mm, the wall thickness is 0.20 mm, the thickness ratio of the inner layer pipe to the outer layer pipe is 1:1, and the distance between the drip holes is 300 mm.

[0056] Example 1

[0057] A polyethylene drip irrigation pipe for preventing crops from being scalded comprises a drip irrigation pipe body and a plurality of patch drippers embedded on the inner wall of the drip irrigation pipe body. The drip irrigation pipe body comprises an inner layer pipe and an outer layer pipe sequentially arranged from the inside to the outside.

[0058] The raw materials of the inner layer tube include the following components in parts by weight: 100 parts of polyethylene LLDPE DFDA7042, 5.7 parts of carbon black, and 3 parts of masterbatch;

[0059] The raw materials of the outer layer tube include the following components in parts by weight: 100 parts of metallocene polyethylene mLLDPE LL7835A, 3 parts of color masterbatch, and 3 parts of PPA masterbatch PPA-1M.

[0060] Example 2

[0061] A polyethylene drip irrigation pipe for preventing crops from being scalded comprises a drip irrigation pipe body and a plurality of patch drippers embedded on the inner wall of the drip irrigation pipe body.

[0062] The drip irrigation pipe body includes an inner layer pipe and an outer layer pipe arranged in sequence from the inside to the outside.

[0063] The raw materials of the inner layer tube include the following components in parts by weight: 100 parts of polyethylene LLDPE DFDA7042, 4.5 parts of carbon black, and 5 parts of masterbatch;

[0064] The raw materials of the outer layer tube include the following components in parts by weight: 100 parts of metallocene polyethylene mLLDPE LL7835A, 5 parts of color masterbatch, and 8 parts of PPA masterbatch PPA-1M.

[0065] Example 3

[0066] The difference between this embodiment and embodiment 1 is that the polyethylene in the inner layer tube is the first polyethylene LLDPEBD20030BA.

[0067] Example 4

[0068] The only difference between this embodiment and embodiment 1 is that the polyethylene in the inner layer tube is the second polyethylene LLDPE 2045G.

[0069] Example 5

[0070] The only difference between this embodiment and embodiment 3 is that in the inner layer tube, the polyethylene is composed of a first polyethylene LLDPE BD20030BA and a second polyethylene LLDPE 2045G in a mass ratio of 1:1.

[0071] Example 6

[0072] The only difference between this embodiment and embodiment 3 is that in the inner layer tube, the polyethylene is composed of a first polyethylene LLDPE BD20030BA and a second polyethylene LLDPE 2045G in a mass ratio of 3:2.

[0073] Example 7

[0074] The difference between this embodiment and embodiment 3 is that in the inner layer tube, the polyethylene is composed of a first polyethylene LLDPE BD20030BA and a second polyethylene LLDPE 2045G in a mass ratio of 2:3.

[0075] Example 8

[0076] The difference between this embodiment and embodiment 3 is that in the inner layer tube, the polyethylene is composed of a first polyethylene LLDPE BD20030BA and a second polyethylene LLDPE 2045G in a mass ratio of 1:4.

[0077] Example 9

[0078] The only difference between this embodiment and embodiment 8 is that the grade of the metallocene polyethylene in the outer tube is mLLDPE2018MA.

[0079] Example 10

[0080] The only difference between this embodiment and embodiment 8 is that the grade of the metallocene polyethylene in the outer tube is mLLDPE2005MC.

[0081] Embodiment 11

[0082] The only difference between this embodiment and embodiment 8 is that the grade of the metallocene polyethylene in the outer tube is mLLDPE2703MC.

[0083] Example 12

[0084] The difference between this embodiment and embodiment 10 is that in the outer tube, the PPA masterbatch includes the following components in parts by weight:

[0085] Linear low-density polyethylene LLDPE 3470 40 parts, ethylene-acrylic acid copolymer EAA 5200 30 parts, antioxidant 1010 5 parts, fluorinated polymer PVDF DS206 2 parts;

[0086] The preparation method of PPA masterbatch comprises the following steps: mixing fluorine-containing polymer PVDF DS206 with linear low-density polyethylene LLDPE 3470, ethylene-acrylic acid copolymer EAA 5200 and antioxidant 1010, extruding and granulating, and drying to obtain PPA masterbatch.

[0087] Embodiment 13

[0088] The only difference between this embodiment and embodiment 12 is that in the outer tube, the PPA masterbatch includes the following components in parts by weight:

[0089] 60 parts of linear low-density polyethylene LLDPE 3470, 50 parts of ethylene-acrylic acid copolymer EAA 5200, 10 parts of antioxidant 1010, and 4 parts of fluorine-containing polymer PVDF DS206.

[0090] Embodiment 14

[0091] The only difference between this embodiment and embodiment 12 is that the grade of the ethylene-acrylic acid copolymer in the outer tube is EAA5080.

[0092] Embodiment 15

[0093] The only difference between this embodiment and embodiment 12 is that the grade of the ethylene-acrylic acid copolymer in the outer tube is EAA5020.

[0094] Example 16

[0095] The only difference between this embodiment and embodiment 12 is that the grade of the ethylene-acrylic acid copolymer in the outer tube is EAA6000.

[0096] Embodiment 17

[0097] The difference between this embodiment and embodiment 10 is that in the outer tube, the PPA masterbatch includes the following components in parts by weight:

[0098] Linear low-density polyethylene LLDPE 3470 40 parts, ethylene-acrylic acid copolymer EAA 5200 30 parts, antioxidant 1010 5 parts, fluorinated polymer PVDF DS206 2 parts, polyvinyl pyrrolidone PVP-K30 1 part;

[0099] The preparation method of PPA masterbatch comprises the following steps: mixing fluorine-containing polymer PVDF DS206 with linear low-density polyethylene LLDPE 3470, ethylene-acrylic acid copolymer EAA 5200, antioxidant 1010 and polyvinyl pyrrolidone PVP-K30, extruding and granulating the mixture, and drying the mixture to obtain PPA masterbatch.

[0100] Embodiment 18

[0101] The only difference between this embodiment and embodiment 17 is that in the outer tube, the PPA masterbatch includes the following components in parts by weight:

[0102] 60 parts of linear low-density polyethylene LLDPE 3470, 50 parts of ethylene-acrylic acid copolymer EAA 5200, 10 parts of antioxidant 1010, 4 parts of fluorine-containing polymer PVDF DS206, and 2 parts of polyvinyl pyrrolidine PVP-K30.

[0103] Comparative Example 1

[0104] The difference between this comparative example and Example 1 is that the drip irrigation pipe body has only one layer, and the raw materials include the following components in parts by weight: 100 parts of polyethylene LLDPE DFDA7042, 2.7 parts of carbon black, and 3 parts of masterbatch.

[0105] Comparative Example 2

[0106] The only difference between this comparative example and Example 1 is that the raw materials of the outer layer tube include the following components in parts by weight: 100 parts of polyethylene LLDPE DFDA7042, 3 parts of color masterbatch, and 3 parts of PPA masterbatch PPA-1M.

[0107] Comparative Example 3

[0108] The only difference between this comparative example and Example 1 is that the raw materials of the outer layer tube include the following components in parts by weight: 100 parts of metallocene polyethylene mLLDPE LL7835A and 3 parts of masterbatch.

[0109] Water pressure resistance can test whether the hydrostatic strength of the drip irrigation pipe can meet the requirements, and the bursting pressure is the maximum pressure value that the drip irrigation pipe can withstand when it bursts. Both aspects can reflect the hydrostatic strength of the drip irrigation belt. Therefore, in order to verify the hydrostatic strength of the drip irrigation pipes of each embodiment and comparative example, the polyethylene drip irrigation pipes prepared in embodiments 1 to 18 and comparative examples 1 to 3 were tested for water pressure resistance and bursting pressure. The test method was carried out in accordance with the method specified in GB / T 19812.3-2017 "Plastic Water-Saving Irrigation Equipment Part 3: Inlaid Drip Irrigation Pipes and Drip Irrigation Belts". The test results are shown in Table 1:

[0110] Table 1 Water pressure resistance and bursting pressure test results

[0111]

[0112] It can be seen from the data in Table 1 that, compared with Comparative Examples 1 to 3, the water pressure resistance test of the polyethylene drip irrigation pipes prepared in Examples 1 to 18 meets the standard requirements, and the bursting pressure is as high as 377.4 kPa or more, indicating that the arrangement of the inner layer tube and the outer layer tube and the use of metallocene polyethylene as the matrix in the outer layer tube and the addition of PPA masterbatch significantly improve the anti-static hydraulic strength of the polyethylene drip irrigation pipe.

[0113] Compared with Example 1, the bursting pressure of the polyethylene drip irrigation pipes prepared in Examples 3 to 8 is higher, and the bursting pressure of the polyethylene drip irrigation pipes in Examples 7 to 8 is higher than that in Examples 3 to 5, indicating that when the melt flow rate of the polyethylene in the outer layer tube is less than 2 g / 10 min at 190° C. and a load of 2.16 kg, the anti-static hydraulic strength of the prepared polyethylene drip irrigation pipe is higher, and when the mass ratio of the first polyethylene to the second polyethylene is 1:4 to 2:3, the anti-static hydraulic strength of the polyethylene drip irrigation pipe is further improved.

[0114] Compared with Example 8 and Example 11, the bursting pressure of the polyethylene drip irrigation pipe prepared in Examples 9-10 is higher, indicating that when the melt flow rate of the metallocene polyethylene in the outer layer tube is 0.5-2.0 g / 10 min at 190° C. and a load of 2.16 kg, the obtained polyethylene drip irrigation pipe has a higher anti-static hydraulic strength.

[0115] Compared with Example 10, the bursting pressure of the polyethylene drip irrigation pipes prepared in Examples 12 to 16 is higher, and the bursting pressure of the polyethylene drip irrigation pipes in Examples 14 to 15 is higher than that in Examples 12 to 13 and Example 16, indicating that when the PPA masterbatch extruded by mixing linear low-density polyethylene, ethylene-acrylic acid copolymer, fluorine-containing polymer, antioxidant, etc. is added to the outer tube, the anti-static hydraulic strength of the polyethylene drip irrigation pipe is further improved, and when the mass content of acrylic acid in the ethylene-acrylic acid copolymer is 7.5% to 10%, the anti-static hydraulic strength of the obtained polyethylene drip irrigation pipe is higher.

[0116] Compared with Examples 12 to 13, the bursting pressure of the polyethylene drip irrigation pipes prepared in Examples 17 and 18 is higher, indicating that when the PPA masterbatch extruded by mixing linear low-density polyethylene, ethylene-acrylic acid copolymer, polyvinyl pyrrolidone, fluorine-containing polymer, antioxidant, etc. is added to the outer layer, the hydrostatic strength of the polyethylene drip irrigation pipe is further improved.

[0117] In addition, the polyethylene drip irrigation pipes prepared in Examples 1 to 18 were tested for pull-out resistance according to the method specified in GB / T 19812.3-2017 "Plastic Water-Saving Irrigation Equipment Part 3: Inlaid Drip Irrigation Pipes and Drip Irrigation Belts". The standard requirements are: the pull-out resistance (110N, 15min) should not show any breakage phenomenon, and the change in the spacing between markings before and after the test is no more than 5%; after testing, the pull-out resistance of the polyethylene drip irrigation pipes prepared in Examples 1 to 18 meets the standard requirements.

[0118] 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 polyethylene drip irrigation pipe for preventing crops from being scalded, comprising a drip irrigation pipe body and a plurality of patch drippers embedded on the inner wall of the drip irrigation pipe body, characterized in that: The drip irrigation pipe body comprises an inner layer pipe and an outer layer pipe arranged in sequence from the inside to the outside. The raw materials of the inner layer tube include the following components in parts by weight: 100 parts of polyethylene, 4.5-5.7 parts of carbon black, and 3-5 parts of masterbatch; the melt flow rate of the polyethylene at 190° C. and 2.16 kg load is less than 2 g / 10 min; The raw materials of the outer layer tube include the following components in parts by weight: 100 parts of metallocene polyethylene, 3-5 parts of color masterbatch, and 3-8 parts of PPA masterbatch; the melt flow rate of the metallocene polyethylene at 190° C. and 2.16 kg load is 0.5-2.0 g / 10 min; the PPA masterbatch includes the following components in parts by weight: 40-60 parts of linear low-density polyethylene, 30-50 parts of ethylene-acrylic acid copolymer, 5-10 parts of antioxidant, 2-4 parts of fluorine-containing polymer; The masterbatch is a silver-grey masterbatch.

2. A polyethylene drip irrigation pipe for preventing crop scalding according to claim 1, characterized in that: The polyethylene includes a first polyethylene and a second polyethylene having different melt flow rates, The melt flow rate of the first polyethylene at 190° C. and 2.16 kg load is 0.2 g / 10 min to 0.5 g / 10 min, The melt flow rate of the second polyethylene at 190° C. and 2.16 kg load is 1 g / 10 min to 1.5 g / 10 min. The mass of the first polyethylene is less than the mass of the second polyethylene.

3. A polyethylene drip irrigation pipe for preventing crop scalding according to claim 2, characterized in that: The mass ratio of the first polyethylene to the second polyethylene is 1:4 to 2:

3.

4. A polyethylene drip irrigation pipe for preventing crop scalding according to claim 1, characterized in that: The mass content of acrylic acid in the ethylene-acrylic acid copolymer is 7.5% to 10%.

5. The polyethylene drip irrigation pipe for preventing crop scalding according to claim 1, characterized in that: The PPA masterbatch also includes 1 to 2 parts of polyvinyl pyrrolidone.

6. A polyethylene drip irrigation pipe for preventing crops from being scalded according to claim 1, characterized in that: The preparation method of the PPA masterbatch comprises the following steps: mixing a fluorine-containing polymer with a linear low-density polyethylene, an ethylene-acrylic acid copolymer and an antioxidant, extruding and granulating the mixture, and drying the mixture to obtain the PPA masterbatch.

7. The polyethylene drip irrigation pipe for preventing crop scalding according to claim 1, characterized in that: The inner diameter of the drip irrigation pipe body is 15.7-16.3 mm, the wall thickness is 0.19-0.24 mm, and the spacing between the drip holes of the patch dripper is 285-315 mm.

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