Production method for recycling waste drip irrigation tape

Abstract

The invention discloses a production method for recycling waste drip irrigation tapes, and belongs to the technical field of recycling of waste drip irrigation tapes, an acidic additive is added into a processing material to change the pH value of the processing material, and a new drip irrigation tape prepared by mixing the obtained acidic processing material with a new material, a color master batch and a processing aid can meet the requirement for tensile strength, and can be used for preparing a new drip irrigation tape. Compared with the drip irrigation tape prepared in the prior art, the new drip irrigation tape prepared by adding 25 parts of the new material, 5 parts of the color master batch, 10 parts of the processing aid and 80 parts of the acidic processing material (the mixing ratio of oxalic acid to acetic acid is 1: 2) has the advantages that the addition amount of the waste drip irrigation tape (processing material) is increased by 6.7%, the tensile strength is increased by 4.8 MPa, and the increasing rate is 9.06%, so that the new drip irrigation tape can be applied to the field of drip irrigation. The acid additive is added into the processing material, so that the utilization rate of the waste drip irrigation tape can be increased, the tensile strength of the drip irrigation tape can be improved, and the problem of contradiction between the tensile strength of the drip irrigation tape and the adding amount of the recycled drip irrigation tape is solved.

Description

Technical Field

[0001] The present application belongs to the technical field of recycling waste drip irrigation tapes, and in particular, relates to a production method for recycling and reusing waste drip irrigation tapes. Technical Background

[0002] Drip irrigation tape uses plastic pipes to deliver water to the roots of crops through orifices or drippers on capillaries with a diameter of about 10 mm for local irrigation. Drip irrigation tape uses plastic pipes to deliver water to the roots of crops through orifices or drippers on capillaries with a diameter of about 10 mm for local irrigation. Drip irrigation tape is generally produced by extrusion molding of polyethylene as raw material. When it is used, it is generally exposed to the natural environment. Due to the influence of the external environment (such as heat, light, oxygen, microorganisms, etc.), photo-oxidation degradation, thermal-oxidation degradation and microbial degradation will occur, which will reduce the molecular weight of polyethylene and cause the performance of the drip irrigation tape to decline, so that the drip irrigation tape cannot meet actual needs.

[0003] For drip irrigation tapes that cannot meet actual needs, it is necessary to recycle these drip irrigation tapes. In the prior art, one of the methods for recycling drip irrigation tapes is to mix the recycled drip irrigation tapes with new materials for producing drip irrigation tapes (without mixing the recycled drip irrigation tapes) to prepare new drip irrigation tapes. However, during the preparation process, it is obviously found that if the tensile strength of the new drip irrigation tape is to be increased, the amount of recycled drip irrigation tape added needs to be reduced, thereby reducing the recycling rate of the recycled drip irrigation tapes.

[0004] For example, a Chinese invention patent with publication number "CN201410837957.1" discloses a composite material of a toughened polypropylene drip irrigation tape and a preparation method thereof, which relates to a composite material of a toughened polypropylene drip irrigation tape and a preparation method thereof. According to the description in the specification, the prepared drip irrigation tape has a tensile strength between 52 and 53 MPa, and the addition amount of polypropylene recycled material (recycled drip irrigation tape) is 60%, reflecting that as the addition amount of polypropylene recycled material (recycled drip irrigation tape) increases, the tensile strength of the new drip irrigation tape will be weakened. Summary of the invention

[0005] The purpose of the present application is to solve the contradiction between the tensile strength of the new drip irrigation tape and the amount of recycled drip irrigation tape added when the new drip irrigation tape is prepared by using the recycled drip irrigation tape in the prior art.

[0006] To achieve the above objectives, this application provides the following technical solutions:

[0007] A production method for recycling and reusing waste drip irrigation tapes, comprising the following steps:

[0008] S1. Crushing the recycled waste drip irrigation tape to obtain crushed old material, and sequentially subjecting the crushed old material to a first water washing, an acid washing, a second water washing, and drying to obtain a processed material;

[0009] S2, adding an acidic additive to the processed material to obtain an acidic processed material, wherein the acidic additive is at least one of oxalic acid and acetic acid, and the amount of the acidic additive added is 0.5wt% to 1wt% of the processed material;

[0010] S3, taking 15 to 25 parts of new material, 4 to 5 parts of masterbatch, 5 to 10 parts of processing aid and 60 to 80 parts of the acidic processing material by weight, mixing, extruding and molding, and making a new drip irrigation tape.

[0011] Preferably, in the step S2, the step of adding an acidic additive to the processed material comprises the following steps:

[0012] An acidic additive is added to the processing material and mixed evenly by a high-speed mixer at a mixing temperature of 30° C. to 50° C. for a mixing time of 1 h to 3 h to obtain the acidic processing material.

[0013] Preferably, in the step S2, the amount of the acidic additive added is 0.7 wt % of the processed material.

[0014] Preferably, in the step S2, the acidic additive is oxalic acid.

[0015] Preferably, in step S2, the acidic additive is a mixture of oxalic acid and acetic acid.

[0016] Preferably, in the acidic additive, the mass ratio of the oxalic acid to the acetic acid is 1:1 to 1:2.

[0017] Preferably, in step S1, the crushed waste material after the first water washing is placed in an acid solution with a mass fraction of 5% to 20% for acid washing.

[0018] Preferably, in the step S3, 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 80 parts of the acidic processing material are mixed by weight.

[0019] Preferably, in the step S3, the processing aid is a silane coupling agent.

[0020] A production method for recycling and reusing waste drip irrigation tapes as described in any one of the above items is used in the field of waste drip irrigation tape recycling and drip irrigation tape preparation.

[0021] Beneficial effect: When a new drip irrigation tape is prepared by using the recycled drip irrigation tape, an acidic additive is added to the processed material to change the pH value of the processed material. The new drip irrigation tape prepared by mixing the obtained acidic processed material with new material, masterbatch and processing aid can meet the tensile strength requirements, that is, the new drip irrigation tape prepared by adding 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 80 parts of the acidic processed material (wherein the mixing ratio of oxalic acid to acetic acid in the acidic additive is 1:2) is different from the prior art (such as a composite material of a toughened polypropylene drip irrigation tape and its preparation method mentioned in the background technology) Compared with the drip irrigation tape prepared by the method, the addition amount of the waste drip irrigation tape in the prior art is 60%, and the tensile strength is between 52 and 53 MPa. The addition amount of the waste drip irrigation tape in the present application is 66.7%, and the tensile strength is 57.8 MPa; compared with the two, the addition amount of the waste drip irrigation tape is increased by 6.7%, and the tensile strength is increased by 4.8 MPa, and the increase rate is 9.06%. It can be seen that adding acidic additives to the processing material can improve the utilization rate of the waste drip irrigation tape, and can also improve the tensile strength of the drip irrigation tape, thereby solving the contradiction between the tensile strength of the drip irrigation tape and the amount of recycled drip irrigation tape added. DETAILED DESCRIPTION

[0022] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present application can be combined with each other. The technical solution of the present application will be further described below, and the present application is not limited to the following specific implementation methods.

[0023] In the description of this application, it should be understood that if there are terms such as "upper", "lower", "front", "back", "left", "right", "top", "bottom", etc. indicating directions or positional relationships, it is only for the convenience of describing this application and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship are only used for illustrative purposes and cannot be understood as limitations on this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0024] A production method for recycling and reusing waste drip irrigation tapes, comprising the following steps:

[0025] S1. Crushing the recycled waste drip irrigation tape to obtain crushed old material, and sequentially subjecting the crushed old material to a first water washing, an acid washing, a second water washing, and drying to obtain a processed material;

[0026] S2, adding an acidic additive to the processed material to obtain an acidic processed material, wherein the acidic additive is at least one of oxalic acid and acetic acid, and the amount of the acidic additive added is 0.5wt% to 1wt% of the processed material;

[0027] S3, taking 15 to 25 parts of new material, 4 to 5 parts of masterbatch, 5 to 10 parts of processing aid and 60 to 80 parts of the acidic processing material by weight, mixing, extruding and molding, and making a new drip irrigation tape.

[0028] First, the recycled drip irrigation tape is crushed, and then the crushed drip irrigation tape is cleaned (in the waste material cleaning step, the crushed recycled drip irrigation tape is placed in an ultrasonic cleaning tank, and the oscillation frequency of the ultrasonic cleaning tank is 0.6-1MHz) to remove the sediment, and then the old material with the sediment removed is acid-soaked to remove the firm scale on the drip irrigation tape, and finally it is cleaned with clean water to ensure that the aqueous solution for cleaning the drip irrigation tape is a neutral aqueous solution to obtain a processed material, and then acid additives are added to the processed material obtained in the above steps to change the pH value of the processed material, and finally the obtained acidic processed material is mixed with new material, masterbatch and processing aid, and then extruded to prepare a new drip irrigation tape.

[0029] At the same time, in the above steps, when adding acidic additives to the processing materials, the water content of the acidic additives should be considered to avoid the new drip irrigation tape being of unqualified quality due to high water content, and the processing aids include additives such as UV protection, antioxidants and antibacterial agents.

[0030] The new material is polyethylene; polyethylene (PE for short) is a thermoplastic resin obtained by polymerization of ethylene. In industry, it also includes copolymers of ethylene and a small amount of α-olefins. Polyethylene is odorless, non-toxic, feels like wax, has excellent low temperature resistance (the lowest operating temperature can reach -100 to -70°C), good chemical stability, and can withstand the corrosion of most acids and alkalis (not resistant to oxidizing acids). It is insoluble in general solvents at room temperature, has low water absorption, and has excellent electrical insulation.

[0031] The function of the masterbatch is to add to the plastic raw materials, such as carbon black, to change the color of the raw materials and enhance the aesthetics and market competitiveness of plastic products. At the same time, the black masterbatch of the drip irrigation tape will also affect the light transmittance, mechanical properties, weather resistance and other characteristics of the plastic products. Different masterbatches can be selected according to the different drip irrigation tapes, and hindered phenol antioxidants, light shielding agents and ultraviolet absorbers need to be added.

[0032] The processing aid is a plastic additive that improves the interface performance between synthetic resin and inorganic filler or reinforcing material in plastic compounding. It is also called surface modifier. It can reduce the viscosity of synthetic resin melt during plastic processing, improve the dispersion of filler to improve processing performance, and then make the product have good surface quality and mechanical, thermal and electrical properties. Coupling agent generally consists of two parts: one part is inorganic affinity group, which can react with inorganic filler or reinforcing material; the other part is organic affinity group, which can react with synthetic resin.

[0033] Specifically, in the step S2, the step of adding the acidic additive to the processed material comprises the following steps:

[0034] An acidic additive is added to the processing material and mixed evenly by a high-speed mixer at a mixing temperature of 30° C. to 50° C. for a mixing time of 1 h to 3 h to obtain the acidic processing material.

[0035] When the processing material and the acidic additive are mixed, if the mixing temperature is high, part of the processing material will melt, while the other part of the processing material will remain in the original state. At this time, the acidic additive and the processing material cannot be evenly mixed. At this time, it is necessary to add the acidic additive while stirring to ensure that the acidic additive and the processing material are evenly contacted and mixed.

[0036] In a preferred embodiment, in the step S2, the amount of the acidic additive added is 0.7 wt % of the processed material.

[0037] When adding the acidic additive, the amount of the acidic additive added cannot be too much. For example, 0.7 kg of the acidic additive is added to 100 kg of the processed material. If too much acidic additive is added, the tensile strength of the newly produced drip irrigation tape will be weakened, and even the processed material may be carbonized.

[0038] Specifically, in the step S2, the acidic additive is oxalic acid.

[0039] The type of the acidic additive may be oxalic acid (pure acid), because oxalate has a strong compatibility and after being mixed with the processing material, it can be better integrated with the processing material in the subsequent granulation and extrusion steps.

[0040] Alternatively, in step S2, the acidic additive is a mixture of oxalic acid and acetic acid.

[0041] When preparing the acidic additive, oxalic acid and acetic acid may be mixed to prepare the acidic additive.

[0042] In a specific embodiment, in the acidic additive, the mass ratio of the oxalic acid to the acetic acid is 1:1 to 1:2.

[0043] When preparing the acidic additive, it is necessary to take into account that acetic acid will volatilize during the preparation process. Therefore, during preparation, the mass ratio of the oxalic acid to the acetic acid is at least 1:1.

[0044] Furthermore, in step S1, the crushed waste material after the first water washing is placed in an acid solution with a mass fraction of 5% to 20% for pickling.

[0045] A large amount of scale will be attached to the inner wall of the recycled drip irrigation tape, which is cleaned with a pickling solution to perform a neutralization reaction to remove the scale on the inner wall of the discarded drip irrigation tape; at the same time, in order to shorten the time of removing the scale attached to the inner wall of the recycled drip irrigation tape, the drip irrigation tape is cut to a suitable length when the old material is pickled. When cutting the drip irrigation tape, it is cut into small sections of different lengths according to the use time and use area of ​​the drip irrigation tape, which improves the descaling efficiency and facilitates the subsequent drying steps.

[0046] Polyethylene is the main raw material of drip irrigation tape. It has high strength and toughness and can withstand the erosion of high temperature, strong acid and alkaline liquid. However, the recycled drip irrigation tape in the natural environment will be affected by the external environment (such as heat, light, oxygen, microorganisms, etc.), and will undergo photo-oxidative degradation, thermal-oxidative degradation and microbial degradation, which will reduce the molecular weight of polyethylene and lead to its performance degradation. At this time, if a pickling solution with a lower pH value, that is, a more acidic pickling solution, is used for descaling, it will react with the old material, such as carbonization; it is even more unfavorable for the subsequent production process, and in the state of strong acid, carbon tetrachloride will be produced in the process of producing drip irrigation tape.

[0047] When the pickling solution is selected, the acid added to the pickling solution is diluted, for example, a large amount of water is added to dilute hydrochloric acid or sulfuric acid to reduce the pH value of the pickling solution.

[0048] In a preferred embodiment, in the step S3, 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 80 parts of the acidic processing material are mixed by weight.

[0049] When preparing a new drip irrigation tape, the ingredients are mixed according to the above ratio to prepare the new drip irrigation tape, so as to meet the daily demand for tensile strength and improve the utilization rate of the recycled drip irrigation tape.

[0050] Or use the following material ratio: 20 parts of new material, 5 parts of masterbatch, 5 parts of processing aid and 70 parts of acidic processing material;

[0051] 20 parts of new material, 5 parts of masterbatch, 5 parts of processing aid and 50 parts of acidic processing material;

[0052] The drip irrigation tape is prepared according to 25 parts of new material, 5 parts of masterbatch, 5 parts of processing aid and 70 parts of acidic processed material.

[0053] Or in another embodiment, a corresponding material ratio may be selected to prepare a new drip irrigation tape to improve the utilization rate of the recycled drip irrigation tape.

[0054] Specifically, in the step S3, the processing aid is a silane coupling agent.

[0055] The general formula of silane coupling agent is RSiX3, where R represents amino, mercapto, vinyl, epoxy, cyano and methacryloxy groups, which have strong reactivity with different base resins, and X represents alkoxy groups (such as methoxy, ethoxy, etc.) that can be hydrolyzed. There are several types of silane coupling agents in China, including KH550, KH560, KH570, KH792, DL602 and DL171. KH550 is selected in this application.

[0056] A production method for recycling and reusing waste drip irrigation tapes as described in any one of the above items is used in the field of waste drip irrigation tape recycling and drip irrigation tape preparation.

[0057] The production method for recycling and reusing the waste drip irrigation tape reasonably uses the waste (recycled) drip irrigation tape. When the recycled drip irrigation tape is used to prepare a new drip irrigation tape, an acidic additive is added to the processed material to change the pH of the processed material. The new drip irrigation tape prepared by mixing the obtained acidic processed material with the new material, the masterbatch and the processing aid can meet the tensile strength requirements. Compared with the drip irrigation tape prepared in the prior art, the addition amount of the waste drip irrigation tape in the prior art is 60%, and the tensile strength is between 52 and 53 MPa. In the present application, the addition amount of the waste drip irrigation tape is 66.7%, and the tensile strength is 57.8 MPa; compared with the two, the addition amount of the waste drip irrigation tape is increased by 6.7%, and the tensile strength is increased by 4.8 MPa, with an increase rate of 9.06%. It can be seen that adding an acidic additive to the processed material can improve the utilization rate of the waste drip irrigation tape, and can also improve the tensile strength of the drip irrigation tape, solving the contradiction between the tensile strength of the drip irrigation tape and the addition amount of the recycled drip irrigation tape.

[0058] In order to enable those skilled in the art to better understand the scheme of the present invention, the present invention is further described in detail below in conjunction with embodiments.

[0059] Unless otherwise specified, the experimental methods used in the embodiments of the present invention are all conventional methods.

[0060] Unless otherwise specified, the materials, reagents, etc. used in the embodiments of the present invention can be obtained from commercial sources.

[0061] Material preparation: new material (polyethylene), masterbatch (carbon black), processing aid (KH550), oxalic acid and acetic acid, all of which are commercially available.

[0062] Preparation of processing materials: The recycled waste drip irrigation tape is crushed to obtain crushed old materials, and the crushing length is about 5 cm. The crushed old materials are then washed with water for the first time, acid washed, and washed with water for the second time. After drying, they are set aside. During this process, the crushed old materials are placed in 10% acid solution (sulfuric acid solution) for acid washing.

[0063] Strength testing instrument: Cut the prepared drip irrigation tape into 40 cm in length, and then put the cut drip irrigation tape on a tensile strength testing machine. The tensile strength testing machine can be a conventional instrument, such as the zipper tensile strength tester HY-1080, and the loading speed of the tensile tester is 10 mm / min.

[0064] Tensile strength testing method:

[0065] During the tensile process, the material enters the strengthening stage after the yield stage, and the transverse cross-sectional size is significantly reduced. The maximum force (Fb) that the material bears when it is pulled apart is divided by the original cross-sectional area (So) of the sample. The stress (σ) is called the tensile strength or ultimate strength (σb), and the unit is N / (MPa). It represents the maximum ability of metal materials to resist damage under tension. The calculation formula is:

[0066] σ=Fb / So

[0067] Where: Fb--the maximum force that the sample bears when it is broken, N (Newton); So--the original cross-sectional area of ​​the sample, mm 2 .

[0068] The technical solutions and technical effects of the present invention are further illustrated below through specific embodiments.

[0069] A block design was adopted and the blocks were divided into 4 groups. For the convenience of marking, each group was marked as blank example: A1, A2, A3; comparative example: B1, B2, B3; Example 1: C1, C2; Example 2: D1, D2, D3, D4, D5; Example 3: E1, E2, E3, E4.

[0070] 1. Blank Example

[0071] 1. Material ratio for preparing drip irrigation tape

[0072] A1: 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 60 parts of the processed material are mixed by mass fraction, and then put into a drip irrigation tape preparation device to prepare a drip irrigation tape.

[0073] A2: 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 80 parts of the processed material are mixed by mass, and then put into a drip irrigation tape preparation device to prepare a drip irrigation tape.

[0074] A3: 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 100 parts of the processed material are mixed by mass, and then put into a drip irrigation tape preparation device to prepare a drip irrigation tape.

[0075] Table 1 Blank Example Material Ratio for Drip Irrigation Tape Preparation

[0076] Group Proportion of processed materials New Materials Masterbatch Processing Aids Processing materials A1 60％ 25 5 10 60 A2 66.7％ 25 5 10 80 A3 71.4％ 25 5 10 100

[0077] Among them: the weight unit of new materials, masterbatches, processing aids and processed materials is kilograms.

[0078] 2. The tensile strength of the drip irrigation tape produced in the above blank example was tested. The results are shown in Table 2.

[0079] Table 2 Detection of tensile strength of blank examples

[0080] Group A1 A2 A3 Tensile strength(MPa) 41.1 46 19

[0081] It can be seen from Table 1 and Table 2 that as the amount of the processed material added (increase in proportion) increases, the tensile strength of the produced drip irrigation tape gradually decreases.

[0082] 2. Comparison

[0083] 1. While keeping other conditions of the blank case unchanged, the processing material in the blank case is replaced with an acidic processing material (see Table 3). Specifically, the preparation of the acidic processing material: take the processing material and oxalic acid (acidic additive), add oxalic acid to the processing material and mix it evenly by a high-speed mixer, the mixing temperature is 40° C., the mixing time is 3 h, and the acidic processing material is obtained. In the acidic processing material, the amount of oxalic acid added is 0.7wt% of the processing material, and more acidic processing material is prepared for standby use. After that, the new material, masterbatch, processing aid and acidic processing material are mixed evenly and put into the drip irrigation tape preparation device to prepare the drip irrigation tape.

[0084] Table 3 Comparative Example of Material Ratios for Preparing Drip Irrigation Tapes

[0085] Group Proportion of acidic processed materials New Materials Masterbatch Processing Aids Acidic processing materials B1 60％ 25 5 10 60 B2 66.7％ 25 5 10 80 B3 71.4％ 25 5 10 100

[0086] 2. The tensile strength of the drip irrigation tape produced in the above comparative example was tested. The results are shown in Table 4.

[0087] Table 4 Detection of tensile strength of comparative examples

[0088] Group B1 B2 B3 Tensile strength(MPa) 45.3 51 21

[0089] It can be seen from Tables 3 and 4 that, without changing the new material, masterbatch and processing aid, after adding oxalic acid to the processed material, it can be obviously found that the tensile strength of the drip irrigation tape becomes higher. The tensile strength of B1 is increased by 10.2% compared with A1, the tensile strength of B2 is increased by 10.9% compared with A2, and the tensile strength of B3 is increased by 10.5% compared with A3. After replacing the processed material with the acidic processed material, the tensile strength of the drip irrigation tape can be effectively improved. The tensile strength of B2 is better than that of B1 and B3, that is, the drip irrigation tape prepared with 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 80 parts of the acidic processed material has a better strength increase.

[0090] 3. Embodiment 1

[0091] 1. While keeping other conditions of Comparative Example B2 unchanged, the type of acidic additive in Comparative Example B2 is replaced with a mixture of acetic acid, oxalic acid and acetic acid (see Table 5), wherein the mixing ratio of oxalic acid and acetic acid is 1:1, and then the new material, masterbatch, processing aid and acidic processing material are mixed evenly (see Table 6) and put into the drip irrigation tape preparation device to prepare the drip irrigation tape.

[0092] Table 5 Preparation of acidic processing materials

[0093] category Number of processed materials Types of Acidic Additives c1 80 acetic acid c2 80 Oxalic acid + acetic acid

[0094] Table 6 Material ratio for preparing drip irrigation tape in Example 1

[0095]

[0096] 2. The tensile strength of the drip irrigation tape produced in Example 1 above was tested. The results are shown in Table 7.

[0097] Table 7 Detection of tensile strength of Example 1

[0098] Group C1 C2 Tensile strength(MPa) 52 54.7

[0099] It can be seen from Tables 5 to 7 that, under the premise of not changing the new material, masterbatch and processing aid, different acidic additives are added to the processed material, and the tensile strength obtained is different. It can be seen from the above table that when the acidic additive is a mixture of oxalic acid and acetic acid, the tensile strength of the prepared new drip irrigation tape is better, and its tensile strength is 1.98% and 6.76% higher than the tensile strength of adding oxalic acid and acetic acid alone, respectively.

[0100] 3. Embodiment 2

[0101] 1. While keeping other conditions of C2 in Example 1 unchanged, the number of added portions of the acidic additive in C2 was changed (see Table 8), and then the new material, masterbatch, processing aid and acidic processed material were mixed evenly (see Table 9) and placed in a drip irrigation tape preparation device to obtain a drip irrigation tape.

[0102] Table 8 Preparation of acidic processing materials

[0103]

[0104] Table 9 Material ratio for preparing drip irrigation tape in Example 2

[0105]

[0106]

[0107] 2. The tensile strength of the drip irrigation tape produced in the above comparative example was tested. The results are shown in Table 10.

[0108] Table 10 Detection of tensile strength of Example 2

[0109] Group D1 D2 D3 D4 D5 Tensile strength(MPa) 41 52.7 52.9 51.7 49.8

[0110] It can be seen from Tables 8 to 10 that, without changing the new material, masterbatch, and processing aid, only the amount of the acidic additive added is changed, and the tensile strength obtained is different. It can be obtained from the above table that the amount of the acidic additive added is 0.5wt% to 1wt% of the processed material, and the strength of the obtained drip irrigation tape is above 50MPa. When the amount of the acidic additive added is less than 0.5wt%, the tensile strength of the obtained drip irrigation tape is poor. When the amount of the acidic additive added exceeds 1wt%, the tensile strength of the obtained drip irrigation tape is reduced. It can be seen from Table 10 that the tensile strength of the drip irrigation tape is similar to a peak. When the amount of the acidic additive added is 0.7wt%, it is a peak value. At both ends of the peak, the tensile strength gradually decreases; it can be seen that the tensile strength of the drip irrigation tape obtained when the amount of the acidic additive added is 0.7wt% is better than the tensile strength of the drip irrigation tape obtained from D1 to D5.

[0111] V. Embodiment 3

[0112] 1. While keeping other conditions of C2 in Example 1 unchanged, the ratio of oxalic acid + acetic acid in C2 was changed (see Table 11), and then the new material, masterbatch, processing aid and acidic processing material were mixed evenly (see Table 12) and placed in a drip irrigation tape preparation device to obtain a drip irrigation tape.

[0113] 1. The ratio of the mixture of oxalic acid and acetic acid is shown in Table 11:

[0114] Table 11 Mixing ratio of oxalic acid and acetic acid

[0115] category e1 e2 e3 e4 Mixing ratio of oxalic acid and acetic acid 1:0.5 1:1.5 1:2 1:2.5

[0116] 2. The material ratios for producing the drip irrigation tape in Example 2 above are shown in Table 12.

[0117] Table 12 Material ratios for preparing drip irrigation tape in Example 3

[0118] Classification Proportion of acidic processed materials New Materials Masterbatch Processing Aids Acidic processing materials E1 66.7％ 25 5 10 80 / e1 E2 66.7％ 25 5 10 80 / e2 E3 66.7％ 25 5 10 80 / e3 E4 66.7％ 25 5 10 80 / e4

[0119] The tensile strength of the drip irrigation tape produced in the above Example 3 was tested, and the results are shown in Table 13.

[0120] Table 13 Detection of tensile strength of Example 3

[0121] E1 E2 E3 E4 Tensile strength(MPa) 50.9 54.1 57.8 51.7

[0122] It can be seen from Tables 11 to 13 that, without changing the types of the new material, masterbatch, processing aid and acidic additive, only changing the mixing ratio of oxalic acid and acetic acid, it is obviously found that the tensile strength will change. The tensile strength of the drip irrigation tape prepared when the mixing ratio of oxalic acid and acetic acid is 1:2 is better, and the tensile strength is 57.8MPa.

[0123] Obviously, the above embodiments of the present application are merely examples for clearly illustrating the present application, and are not intended to limit the implementation methods of the present application. For those of ordinary skill in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all implementation methods here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present application should be included in the protection scope of the present application.

Claims

1. A production method for recycling and reusing waste drip irrigation tapes, characterized in that: The following steps are involved: S1. The recycled waste drip irrigation tape is crushed to obtain crushed old material, and the crushed old material is sequentially subjected to a first water washing, an acid washing, a second water washing, and drying to obtain a processed material; S2, adding an acidic additive to the processed material to obtain an acidic processed material, wherein the acidic additive is at least one of oxalic acid and acetic acid, and the amount of the acidic additive added is 0.5wt% to 1wt% of the processed material; S3, taking 15 to 25 parts of new material, 4 to 5 parts of masterbatch, 5 to 10 parts of processing aid and 60 to 80 parts of the acidic processing material by weight, mixing, extruding and molding, and making a new drip irrigation tape.

2. The production method for recycling and reusing waste drip irrigation tapes according to claim 1, characterized in that: In the step S2, the step of adding an acidic additive to the processed material comprises the following steps: An acidic additive is added to the processing material and mixed evenly by a high-speed mixer at a mixing temperature of 30° C. to 50° C. for a mixing time of 1 h to 3 h to obtain the acidic processing material.

3. The production method for recycling and reusing waste drip irrigation tapes according to claim 1, characterized in that: In the step S2, the amount of the acidic additive added is 0.7 wt % of the processed material.

4. The production method for recycling and reusing waste drip irrigation tapes according to claim 1, characterized in that: In the step S2, the acidic additive is oxalic acid.

5. The production method for recycling and reusing waste drip irrigation tapes according to claim 1, characterized in that: In the step S2, the acidic additive is a mixture of oxalic acid and acetic acid.

6. The production method for recycling and reusing waste drip irrigation tapes according to claim 5, characterized in that: In the acidic additive, the mass ratio of the oxalic acid to the acetic acid is 1:1 to 1:

2.

7. The production method for recycling and reusing waste drip irrigation tapes according to claim 1, characterized in that: In the step S1, the crushed waste material after the first water washing is placed in an acid solution with a mass fraction of 5% to 20% for pickling.

8. The production method for recycling and reusing waste drip irrigation tapes according to claim 7, characterized in that: In the step S3, 25 parts of the new material, 5 parts of the masterbatch, 10 parts of the processing aid and 80 parts of the acidic processing material are mixed by weight.

9. The production method for recycling and reusing waste drip irrigation tapes according to claim 1, characterized in that: In the step S3, the processing aid is a silane coupling agent.

10. Application of the production method for recycling and reusing waste drip irrigation tapes as claimed in any one of claims 1 to 9 in the field of recycling and preparing waste drip irrigation tapes.

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