Preparation method of high-strength anti-puncture tear-resistant agricultural mulching film

Abstract

The invention relates to a preparation method of a high-strength anti-puncture tear-resistant agricultural mulching film, and belongs to the technical field of agricultural mulching films. The preparation method comprises the following steps: stirring and mixing linear low-density polyethylene, modified polypropylene, nano calcium carbonate, montmorillonite, a polyolefin elastomer, an antioxidant, an ultraviolet light absorber and a lubricant, adding the mixture into a double-screw extruder, carrying out melt blending, and granulating by a granulator to obtain composite master batch; adding the composite master batch into a blow molding machine, carrying out blow molding, traction and rolling, feeding into an ultraviolet reaction kettle, adding ethyl acetate, 2-aminothiazolo [4, 5-b] pyridine, acetic anhydride, HMPP and p-toluenesulfonic acid into a dip-coating tank in the kettle, and carrying out ultrasonic dispersion to obtain a mixed solution; turning on an ultraviolet lamp, coating the upper surface of the film with the mixed solution, and performing dip-coating on the lower surface of the film through a dip-coating tank; neutralizing and drying to obtain the high-strength anti-puncture tear-resistant agricultural mulching film. The prepared agricultural mulching film is high in tensile strength, puncture strength and tear strength, and can meet the requirements of complex field environments.

Description

Technical Field

[0001] This invention relates to the field of agricultural mulch film technology, and in particular to a method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film. Background Technology

[0002] Agricultural mulch film, as an important material in agricultural production, plays a vital role in heat preservation, moisture retention, fertilizer retention, and weed suppression, and is widely used in the cultivation of vegetables, fruits, and grains. However, with the development of large-scale and mechanized agriculture, traditional agricultural mulch film has gradually revealed problems such as low strength, susceptibility to puncture, and poor tear resistance. During field operations, the mulch film is easily torn by gravel in the soil, plant roots, or agricultural machinery, leading to its failure. This not only affects agricultural production but also generates a large amount of residual film, polluting the soil environment.

[0003] Chinese Patent CN106009710A discloses an agricultural mulch film and its production process, relating to the field of agricultural mulch film preparation technology. The agricultural mulch film, by weight, contains: 15-20 parts sodium caseinate, 8-14 parts low-density polyethylene resin, 5-7 parts ultrafine calcium carbonate, 1-3 parts acrylate, 5-8 parts polymethyl ethylene carbonate, 3-5 parts maifanite, 5-8 parts nano titanium dioxide, 3-5 parts gum arabic, 1-3 parts insecticide, 8-10 parts ethyl acetate, 20-25 parts PBM degradable material, 5-9 parts tributyl acetylacetonate, 8-10 parts ultraviolet absorber, and 3-5 parts opening agent.

[0004] Chinese Patent CN112341695A discloses a method for preparing agricultural mulch film; it relates to the field of agricultural mulch film technology and includes the following steps: (1) obtaining bentonite powder; (2) obtaining treated bentonite powder; (3) obtaining modified bentonite powder; (4) mixing the modified bentonite powder and polyethylene resin together, then adding them to a twin-screw extruder for melt extrusion, and then transferring them to a blown film machine for blown film to obtain agricultural mulch film.

[0005] Agricultural mulch films prepared using existing technologies are insufficient to meet the needs of complex field environments, and their puncture and tear resistance properties need further improvement. Summary of the Invention

[0006] To address the aforementioned problems, this invention provides a method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film. The operational steps are as follows, in parts by weight: S1 Blending Granulation: 50-70 parts of linear low-density polyethylene, 15-25 parts of modified polypropylene, 4-7 parts of nano-calcium carbonate, 1-3 parts of montmorillonite, 5-10 parts of polyolefin elastomer, 0.2-2 parts of antioxidant, 0.1-1 parts of ultraviolet absorber, and 0.08-0.8 parts of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: Feed the agricultural mulch film roll into the ultraviolet reaction vessel through the unwinding roller, and unfold it horizontally through the guide roller; add 163-326 parts of ethyl acetate, 18-25 parts of 2-aminothiazo[4,5-b]pyridine, and 9-15 parts of acetic anhydride to the dipping tank in the vessel, and add 0.3-0.8 parts of HMPP and 0.2-0.6 parts of p-toluenesulfonic acid while stirring, and ultrasonically disperse for 5-10 minutes to obtain a mixture; S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 12-18cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 30-45 minutes. S5: Neutralize the film surface to pH=7 by spraying with 3-5wt% sodium bicarbonate solution, and dry with hot air to obtain high-strength puncture-resistant and tear-resistant agricultural mulch film.

[0007] In some embodiments, the extrusion temperature of the S1 twin-screw extruder is 160-190°C.

[0008] In some embodiments, the screw speed of the S1 twin-screw extruder is 300-400 r / min.

[0009] In some embodiments, the blow molding temperature of the S2 blow molding machine is 165-180°C, and the blow-up ratio is 2.0-2.5.

[0010] In some embodiments, the antioxidant is one of antioxidant 1010, antioxidant 1076, antioxidant 1098, and antioxidant 168.

[0011] In some embodiments, the ultraviolet absorber is one of UV-0, UV-9, and UV-531.

[0012] In some embodiments, the lubricant is one of calcium stearate, magnesium stearate, and zinc stearate.

[0013] In some embodiments, the method for preparing the modified polypropylene is as follows: 50-70 parts of polypropylene, 1-3 parts of maleic anhydride, and 0.1-0.5 parts of benzoyl peroxide initiator are reacted at 170-180℃ for 10-15 minutes, cooled, and then pulverized to obtain modified polypropylene.

[0014] In some embodiments, the thickness of the agricultural mulch film is 0.012-0.015 mm.

[0015] In some embodiments, the S5 hot air drying temperature is 60-70°C and the time is 5-8 minutes.

[0016] Reaction mechanism: Ultraviolet light activates the hydroxyl (-OH) and carbonyl (C=O) groups of HMPP, causing the carbonyl groups to cleave and produce free radicals, which initiate the esterification of the acyloxy group (-O-CO-CH3) of acetic anhydride with the hydroxyl group (-OH) of the hydroxyl compound; the sulfonic acid group (-SO3H) of p-toluenesulfonic acid (donates protons to promote the reaction); the hydroxyl (-OH) groups (covalently bonded) and carboxyl groups (-COOH) groups (crosslinked) on the surface of the polyethylene film participate in enhancing the film strength.

[0017] Technical effect This invention discloses a method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film. Compared with existing technologies, this invention has the following significant advantages: 1. Significantly improves the puncture resistance of agricultural mulch film, resisting puncture damage from weeds, stones, or agricultural machinery operations, and reducing the decline in soil moisture retention caused by mulch film damage.

[0018] 2. Enhance the tear resistance of the mulch film, making it less prone to tearing due to pulling or external forces during installation and use, thus extending the service life of the mulch film. Detailed Implementation

[0019] To further illustrate the technical means and effects of the present invention in achieving the intended purpose, the following detailed description of the specific implementation methods and effects of the present invention, in conjunction with embodiments, is provided below.

[0020] 1. Tensile strength: Tested according to GB / T1040.3-2006 "Determination of tensile properties of plastics - Part 3: Test conditions for films and sheets" using a universal testing machine.

[0021] 2. Puncture strength: The puncture strength test shall be conducted in accordance with the puncture strength test method in GB / T10004-2008 "Packaging Plastic Composite Films and Bags Dry Lamination and Extrusion Lamination".

[0022] 3. Tear strength: Tested according to GB / T11999-1989 "Test method for tear resistance of plastic films and sheets - trouser tear method" using a tear strength tester.

[0023] Example 1 A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps: S1 Blending Granulation: 50g of linear low-density polyethylene DFDA-7042, 15g of modified polypropylene, 4g of nano calcium carbonate, 1g of montmorillonite, 5g of polyolefin elastomer DOW7467, 0.2g of antioxidant, 0.1g of ultraviolet absorber, and 0.08g of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: The agricultural film roll is fed into the ultraviolet reaction vessel through the unwinding roller and horizontally unfolded by the guide roller; 163g of ethyl acetate, 18g of 2-aminothiazo[4,5-b]pyridine and 9g of acetic anhydride are added to the dipping tank in the vessel, and 0.3g of HMPP and 0.2g of p-toluenesulfonic acid are added under stirring. The mixture is ultrasonically dispersed for 5 minutes to obtain a mixed solution. S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 12cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 30 minutes. S5: Neutralize the film surface to pH=7 by spraying with 3wt% sodium bicarbonate solution, and dry with hot air to obtain high-strength puncture-resistant and tear-resistant agricultural mulch film.

[0024] The extrusion temperature of the S1 twin-screw extruder is 160°C.

[0025] The screw speed of the S1 twin-screw extruder is 300 r / min.

[0026] The blow molding temperature of the S2 blow molding machine is 165℃, and the blow-up ratio is 2.0.

[0027] The antioxidant mentioned is antioxidant 1010.

[0028] The ultraviolet absorber mentioned is UV-0.

[0029] The lubricant is calcium stearate.

[0030] The method for preparing the modified polypropylene is as follows: 50g of polypropylene K7726, 1g of maleic anhydride, and 0.1g of benzoyl peroxide initiator were reacted at 170℃ for 10min, cooled, and then pulverized to obtain modified polypropylene.

[0031] The thickness of the agricultural mulch film is 0.0125 mm.

[0032] The S5 hot air drying temperature is 60℃ and the time is 5 minutes.

[0033] Example 2 A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps: S1 Blending Granulation: 55g of linear low-density polyethylene DFDA-7042, 18g of modified polypropylene, 5g of nano calcium carbonate, 2g of montmorillonite, 6g of polyolefin elastomer DOW7467, 1g of antioxidant, 0.5g of ultraviolet absorber, and 0.3g of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: The agricultural film roll is fed into the ultraviolet reaction vessel through the unwinding roller and horizontally unfolded by the guide roller; 222g of ethyl acetate, 20g of 2-aminothiazo[4,5-b]pyridine and 11g of acetic anhydride are added to the dipping tank in the vessel, and 0.4g of HMPP and 0.3g of p-toluenesulfonic acid are added under stirring. The mixture is ultrasonically dispersed for 6 minutes to obtain a mixed solution. S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 14cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 35 minutes. S5: Neutralize the film surface to pH=7 by spraying with 4wt% sodium bicarbonate solution, and dry with hot air to obtain high-strength puncture-resistant and tear-resistant agricultural mulch film.

[0034] The extrusion temperature of the S1 twin-screw extruder is 170°C.

[0035] The screw speed of the S1 twin-screw extruder is 350 r / min.

[0036] The blow molding temperature of the S2 blow molding machine is 170℃, and the blow-up ratio is 2.1.

[0037] The antioxidant mentioned is antioxidant 1076.

[0038] The ultraviolet absorber mentioned is UV-9.

[0039] The lubricant is magnesium stearate.

[0040] The method for preparing the modified polypropylene is as follows: 55g of polypropylene K7726, 2g of maleic anhydride, and 0.2g of benzoyl peroxide initiator were reacted at 175℃ for 11min, cooled, and then pulverized to obtain modified polypropylene.

[0041] The thickness of the agricultural mulch film is 0.013 mm.

[0042] The S5 hot air drying temperature is 65℃ and the time is 6 minutes.

[0043] Example 3 A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps: S1 Blending Granulation: 65g of linear low-density polyethylene DFDA-7042, 23g of modified polypropylene, 6g of nano calcium carbonate, 2g of montmorillonite, 8g of polyolefin elastomer DOW7467, 1.5g of antioxidant, 0.8g of ultraviolet absorber, and 0.6g of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: The agricultural mulch film roll is fed into the ultraviolet reaction vessel through the unwinding roller and horizontally unfolded by the guide roller; 300g ethyl acetate, 23g 2-aminothiazo[4,5-b]pyridine and 13g acetic anhydride are added to the dipping tank in the vessel, and 0.7g HMPP and 0.5g p-toluenesulfonic acid are added under stirring. The mixture is ultrasonically dispersed for 8 minutes to obtain a mixed solution. S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 16cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 40 minutes. S5: Neutralize the film surface to pH=7 by spraying with 4wt% sodium bicarbonate solution, and dry with hot air to obtain high-strength puncture-resistant and tear-resistant agricultural mulch film.

[0044] The extrusion temperature of the S1 twin-screw extruder is 180℃.

[0045] The screw speed of the S1 twin-screw extruder is 350 r / min.

[0046] The blow molding temperature of the S2 blow molding machine is 175℃, and the blow-up ratio is 2.4.

[0047] The antioxidants mentioned are 1098 kinds of antioxidants.

[0048] The ultraviolet absorber mentioned is UV-9.

[0049] The lubricant is magnesium stearate.

[0050] The method for preparing the modified polypropylene is as follows: 65g of polypropylene K7726, 2g of maleic anhydride, and 0.4g of benzoyl peroxide initiator were reacted at 175℃ for 14min, cooled, and then pulverized to obtain modified polypropylene.

[0051] The thickness of the agricultural mulch film is 0.014 mm.

[0052] The S5 hot air drying temperature is 65℃ and the time is 7 minutes.

[0053] Example 4 A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps: S1 Blending Granulation: 70g of linear low-density polyethylene DFDA-7042, 25g of modified polypropylene, 7g of nano calcium carbonate, 3g of montmorillonite, 10g of polyolefin elastomer DOW7467, 2g of antioxidant, 1g of ultraviolet absorber, and 0.8g of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: The agricultural film roll is fed into the ultraviolet reaction vessel through the unwinding roller and horizontally unfolded by the guide roller; 26g ethyl acetate, 25g 2-aminothiazo[4,5-b]pyridine and 15g acetic anhydride are added to the dipping tank in the vessel, and 0.8g HMPP and 0.6g p-toluenesulfonic acid are added under stirring. The mixture is ultrasonically dispersed for 10 minutes to obtain a mixed solution. S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 18cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 45 minutes. S5: Neutralize the film surface to pH=7 by spraying with 5wt% sodium bicarbonate solution, and dry with hot air to obtain high-strength puncture-resistant and tear-resistant agricultural mulch film.

[0054] The extrusion temperature of the S1 twin-screw extruder is 190°C.

[0055] The screw speed of the S1 twin-screw extruder is 400 r / min.

[0056] The blow molding temperature of the S2 blow molding machine is 180℃, and the blow-up ratio is 2.5.

[0057] The antioxidant mentioned is antioxidant 1098.

[0058] The ultraviolet absorber mentioned is UV-531.

[0059] The lubricant is zinc stearate.

[0060] The method for preparing the modified polypropylene is as follows: 70g of polypropylene K7726, 3g of maleic anhydride, and 0.5g of benzoyl peroxide initiator were reacted at 180℃ for 15min, cooled, and then pulverized to obtain modified polypropylene.

[0061] The thickness of the agricultural mulch film is 0.015 mm.

[0062] The S5 hot air drying temperature is 70℃ and the time is 8 minutes.

[0063] Comparative Example 1 A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps: S1 Blending Granulation: 50g of linear low-density polyethylene DFDA-7042, 15g of modified polypropylene, 4g of nano calcium carbonate, 1g of montmorillonite, 5g of polyolefin elastomer DOW7467, 0.2g of antioxidant, 0.1g of ultraviolet absorber, and 0.08g of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, a high-strength puncture-proof and tear-resistant agricultural mulch film is obtained.

[0064] The extrusion temperature of the S1 twin-screw extruder is 160°C.

[0065] The screw speed of the S1 twin-screw extruder is 300 r / min.

[0066] The blow molding temperature of the S2 blow molding machine is 165℃, and the blow-up ratio is 2.0.

[0067] The antioxidant mentioned is antioxidant 1010.

[0068] The ultraviolet absorber mentioned is UV-0.

[0069] The lubricant is calcium stearate.

[0070] The method for preparing the modified polypropylene is as follows: 50g of polypropylene K7726, 1g of maleic anhydride, and 0.1g of benzoyl peroxide initiator were reacted at 170℃ for 10min, cooled, and then pulverized to obtain modified polypropylene.

[0071] The thickness of the agricultural mulch film is 0.0125 mm.

[0072] Comparative Example 2 A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps: S1 Blending Granulation: 50g of linear low-density polyethylene DFDA-7042, 15g of modified polypropylene, 4g of nano calcium carbonate, 1g of montmorillonite, 5g of polyolefin elastomer DOW7467, 0.2g of antioxidant, 0.1g of ultraviolet absorber, and 0.08g of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: The agricultural film roll is fed into the ultraviolet reaction vessel through the unwinding roller and horizontally unfolded by the guide roller; 163g of ethyl acetate and 9g of acetic anhydride are added to the dipping tank in the vessel, and 0.3g of HMPP and 0.2g of p-toluenesulfonic acid are added under stirring. The mixture is ultrasonically dispersed for 5 minutes to obtain a mixed solution. S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 12cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 30 minutes. S5: Neutralize the film surface to pH=7 by spraying with 3wt% sodium bicarbonate solution, and dry with hot air to obtain high-strength puncture-resistant and tear-resistant agricultural mulch film.

[0073] The extrusion temperature of the S1 twin-screw extruder is 160°C.

[0074] The screw speed of the S1 twin-screw extruder is 300 r / min.

[0075] The blow molding temperature of the S2 blow molding machine is 165℃, and the blow-up ratio is 2.0.

[0076] The antioxidant mentioned is antioxidant 1010.

[0077] The ultraviolet absorber mentioned is UV-0.

[0078] The lubricant is calcium stearate.

[0079] The method for preparing the modified polypropylene is as follows: 50g of polypropylene K7726, 1g of maleic anhydride, and 0.1g of benzoyl peroxide initiator were reacted at 170℃ for 10min, cooled, and then pulverized to obtain modified polypropylene.

[0080] The thickness of the agricultural mulch film is 0.0125 mm.

[0081] The S5 hot air drying temperature is 60℃ and the time is 5 minutes.

[0082] Comparative Example 3 A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps: S1 Blending Granulation: 50g of linear low-density polyethylene DFDA-7042, 15g of modified polypropylene, 4g of nano calcium carbonate, 1g of montmorillonite, 5g of polyolefin elastomer DOW7467, 0.2g of antioxidant, 0.1g of ultraviolet absorber, and 0.08g of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: The agricultural film roll is fed into the UV reactor through the unwinding roller and horizontally unfolded by the guide roller; 163g of ethyl acetate and 18g of 2-aminothiazo[4,5-b]pyridine are added to the dipping tank in the reactor, and 0.3g of HMPP and 0.2g of p-toluenesulfonic acid are added under stirring. The mixture is ultrasonically dispersed for 5 minutes to obtain a mixed solution. S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 12cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 30 minutes. S5: Neutralize the film surface to pH=7 by spraying with 3wt% sodium bicarbonate solution, and dry with hot air to obtain a strong puncture-resistant and tear-resistant agricultural mulch film.

[0083] The extrusion temperature of the S1 twin-screw extruder is 160°C.

[0084] The screw speed of the S1 twin-screw extruder is 300 r / min.

[0085] The blow molding temperature of the S2 blow molding machine is 165℃, and the blow-up ratio is 2.0.

[0086] The antioxidant mentioned is antioxidant 1010.

[0087] The ultraviolet absorber mentioned is UV-0.

[0088] The lubricant is calcium stearate.

[0089] The method for preparing the modified polypropylene is as follows: 50g of polypropylene K7726, 1g of maleic anhydride, and 0.1g of benzoyl peroxide initiator were reacted at 170℃ for 10min, cooled, and then pulverized to obtain modified polypropylene.

[0090] The thickness of the agricultural mulch film is 0.0125 mm.

[0091] The S5 hot air drying temperature is 60℃ and the time is 5 minutes.

[0092] Table 1. Test results of tensile strength, puncture strength, and tear strength of agricultural mulch films in the examples and comparative examples.

[0093] The tensile strength, puncture strength, and tear strength test results of the agricultural mulch film of the present invention (1-4) are higher than those of the comparative examples (1-3), indicating that the agricultural mulch film prepared by the present invention has high tensile strength, high puncture strength, and high tear strength, which can meet the needs of complex field environments.

[0094] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention in any way. Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Any person skilled in the art can make some modifications or alterations to the above-disclosed technical content to create equivalent embodiments without departing from the scope of the present invention. Any simple modifications, equivalent changes and alterations made to the above embodiments based on the technical essence of the present invention without departing from the scope of the present invention shall still fall within the scope of the present invention.

Claims

1. A method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film, comprising the following steps, in parts by weight: S1 Blending Granulation: 50-70 parts of linear low-density polyethylene, 15-25 parts of modified polypropylene, 4-7 parts of nano-calcium carbonate, 1-3 parts of montmorillonite, 5-10 parts of polyolefin elastomer, 0.2-2 parts of antioxidant, 0.1-1 parts of ultraviolet absorber, and 0.08-0.8 parts of lubricant are stirred and mixed, then added to a twin-screw extruder, melt-blended, and granulated by a pelletizer to obtain composite masterbatch; S2 blow molding: The composite masterbatch is added to the blow molding machine, and after blow molding, traction and winding, agricultural mulch film rolls are obtained; S3: Feed the agricultural mulch film roll into the ultraviolet reaction vessel through the unwinding roller, and unfold it horizontally through the guide roller; add 163-326 parts of ethyl acetate, 18-25 parts of 2-aminothiazo[4,5-b]pyridine, and 9-15 parts of acetic anhydride to the dipping tank in the vessel, and add 0.3-0.8 parts of HMPP and 0.2-0.6 parts of p-toluenesulfonic acid while stirring, and ultrasonically disperse for 5-10 minutes to obtain a mixture; S4: Turn on the UV lamp array and adjust the lamp distance to the membrane surface to 12-18cm; the roller coating device coats the mixture onto the upper surface of the membrane, and the lower surface of the membrane is dipped in the dip coating tank. The membrane is continuously transported and reacted under the lamp array for 30-45 minutes. S5: Neutralize the film surface to pH=7 by spraying with 3-5wt% sodium bicarbonate solution, and dry with hot air to obtain high-strength puncture-proof and tear-resistant agricultural mulch film; The modified polypropylene is prepared by reacting polypropylene, maleic anhydride, and benzoyl peroxide initiator.

2. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The extrusion temperature of the S1 twin-screw extruder is 160-190℃.

3. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The screw speed of the S1 twin-screw extruder is 300-400 r / min.

4. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The blow molding temperature of the S2 blow molding machine is 165-180℃, and the blow-up ratio is 2.0-2.

5.

5. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The antioxidant is one of antioxidant 1010, antioxidant 1076, antioxidant 1098, and antioxidant 168.

6. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The ultraviolet absorber is one of UV-0, UV-9, and UV-531.

7. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The lubricant is one of calcium stearate, magnesium stearate, and zinc stearate.

8. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The method for preparing the modified polypropylene is as follows: 50-70 parts of polypropylene, 1-3 parts of maleic anhydride, and 0.1-0.5 parts of benzoyl peroxide initiator are reacted at 170-180℃ for 10-15 minutes, cooled, and then pulverized to obtain modified polypropylene.

9. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The thickness of the agricultural mulch film is 0.012-0.015 mm.

10. The method for preparing a high-strength, puncture-resistant, and tear-resistant agricultural mulch film according to claim 1, characterized in that: The S5 hot air drying temperature is 60-70℃, and the time is 5-8 minutes.

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