Wear-resistant self-cleaning PE film and preparation method thereof

Abstract

The application discloses a wear-resistant self-cleaning polyethylene film and a preparation method thereof. The wear-resistant self-cleaning PE film is prepared from the following raw materials in parts by weight: LLDPE 90 parts, wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@OMMT 2-5 parts, antioxidant 1010 0.5-1 part, antioxidant DLTP 0.5-1 part, and polyethylene wax 1-3 parts. The components are put into a mixer and uniformly mixed, and then the mixture is dried, extruded, granulated, extruded and cast, mirror surface is pressed, cooled, edged, and pressure-wound to obtain the wear-resistant self-cleaning PE film. In the application, OMMT modified by an organic modifier is used as a carrier, SiO2 modified by hydrophobicity is first loaded, and then combined with ZrO2, so that the obtained wear-resistant self-cleaning agent has excellent wear resistance and good self-cleaning performance. Meanwhile, ZrO2 / FSi-SiO2@OMMT, as a rigid medium with excellent performance, improves the mechanical properties of the composite material.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of polymer composite processing, and particularly relates to a wear-resistant self-cleaning PE film and a preparation method thereof. BACKGROUND

[0002] Polyethylene (PE) is a thermoplastic resin prepared by polymerization of ethylene, and the production thereof accounts for about 1 / 4 of the total amount of plastics, and the proportion of film is close to 50%. PE is widely used in life, such as the production of film, daily necessities, various sizes of hollow containers for industry, pipe materials, calendaring tapes and ligature tapes for packaging, ropes, fishing nets and woven fibers, electric wires and cables, etc. The large-scale application of polyethylene is not only because of its excellent chemical properties, such as excellent low-temperature resistance, acid and alkali corrosion resistance, but also because of its excellent mechanical properties, such as high toughness and strength, high tensile and compressive strength, high impact strength and good impact resistance. With the development of modern society, polyethylene film has been widely used in daily life due to its heat resistance, cold resistance, moisture retention and other properties. Functional polyethylene film has attracted widespread attention to meet the needs of people's life. However, in the actual application process, the outer surface of the polyethylene film is easy to adsorb a large amount of dust, which is due to the influence of various small molecular additives, light and heat aging; at the same time, the wear of the polyethylene film in use is also serious. Therefore, it is urgent to develop a polyethylene film with wear resistance and self-cleaning performance.

[0003] Silicon dioxide is a non-toxic and non-polluting particle, which is chemically stable, has good thermal stability and weather resistance, and nano-silicon dioxide has high specific surface area and good dispersibility. Due to these unique properties, nano-silicon dioxide has a wide range of applications. Zirconium dioxide has certain ultraviolet absorption function, excellent chemical stability, thermal stability, non-toxicity and other properties. Smaller zirconium dioxide has greater activity and good dispersibility, which determines that zirconium dioxide is an inorganic raw material with wide application and excellent application prospect.

[0004] Montmorillonite (MMT) is composed of nanometer-thick surface negatively charged silicate layers, which are stacked together by electrostatic interaction between layers. The unit cell in its crystal structure is composed of two layers of silicon-oxygen tetrahedron sandwiching one layer of aluminum-oxygen octahedron, forming a unique one-dimensional layered nanostructure. As a natural and inexpensive material, MMT may be a good choice for constructing micrometer-scale roughness due to its micrometer-scale layered structure. Moreover, MMT has strong adsorption capacity and cation exchange performance, which is due to the presence of a large number of exchangeable cations and water molecules between the layers, making the interlayer domain have interlayer exchange, interlayer adsorption and other characteristics. Therefore, in order to improve the performance of MMT, it is usually inorganic or organic modified. Organic modification changes the surface polarity and interlayer spacing of MMT by adding organic modifiers, thereby enhancing its dispersibility and compatibility in the polymer matrix. SUMMARY

[0005] The purpose of the present application is to provide a wear-resistant self-cleaning PE film and a preparation method thereof. The formula of the present application is scientific and reasonable, and the process flow is simple and practical. By adding a wear-resistant self-cleaning agent, the produced PE film has excellent wear-resistant and self-cleaning properties.

[0006] To achieve the above-mentioned purpose, the technical scheme adopted by the present application is as follows:

[0007] The present application provides a wear-resistant self-cleaning polyethylene film, which comprises the following raw materials in weight fraction:

[0008] LLDPE 90 parts;

[0009] wear-resistant self-cleaning agent 2-5 parts;

[0010] antioxidant 1010 0.5-1 parts;

[0011] polyethylene wax 1-3 parts;

[0012] antioxidant DLTP 0.5-1 parts;

[0013] The wear-resistant self-cleaning agent is ZrO2 / FSi-SiO2@OMMT.

[0014] The preparation method of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@OMMT comprises the following steps:

[0015] (1) Preparation of OMMT: 3 g of micron-sized montmorillonite is added to 120 mL of deionized water, stirred at room temperature for 30 minutes, and 0.1 mol / L NaOH solution is added to adjust the pH of the solution to 12. Continue to stir at 80 ℃ for 3 hours; 1.9 g of cetyltrimethylammonium bromide is dissolved in 50 mL of deionized water and added to the above solution and continue to stir for 3 hours. After the reaction is completed, centrifuge, wash and dryback obtaining OMMT;

[0016] (2) Preparation of FSi-SiO2: 5 mL of tetraethyl orthosilicate was added to a mixed solution of ethanol and ammonia water, and was left to stand for 3 h to obtain SiO2 sol; 0.37 g of KH-570 was added to the SiO2 sol, and was uniformly stirred at 60 ℃ for 2 h, and after the reaction was completed, centrifugation and drying were performed to obtain FSi-SiO2;

[0017] (3) Preparation of ZrO2 / FSi-SiO2@OMMT: 2.30 g of FSi-SiO2 and 1.50 g of ZrO2 were added to 20 mL of deionized water, and the pH of the solution was adjusted to 3 with hydrochloric acid, and was stirred at 60 ℃ for 30 min; 2.50 g of perfluorooctyltriethoxysilane and 7.50 g of OMMT were added, and were refluxed at 60 ℃ for 13 h; after the reaction was completed, the obtained solution was dried at 50 ℃, and was ground through a sieve to obtain powder-shaped ZrO2 / FSi-SiO2@OMMT.

[0018] Further, the volume ratio of ethanol and ammonia water in step (2) is 10:1.

[0019] The application further provides a preparation method of the wear-resistant and self-cleaning polyethylene film.

[0020] (1) The wear-resistant and self-cleaning agent, the antioxidant 1010, the antioxidant DLTP and the polyethylene wax are uniformly mixed, and then are added into a high-speed stirring machine to be uniformly mixed with LLDPE particles, and are dried at 60 ℃ for 1 h;

[0021] (2) The dried material is added into a double-screw extruder to be extruded and granulated to obtain a master batch;

[0022] (3) The obtained master batch is dried, and is added into a casting machine to be extruded and cast, mirror surface pressed, cooled, edge cut, and pressure wound, so that the wear-resistant and self-cleaning PE film is obtained.

[0023] Further, the rotating speed of the high-speed stirring machine in step (1) is 300 r / min, and the temperature is 60 ℃.

[0024] Further, the extrusion temperature of the double-screw extruder used in step (2) is: 150 ℃ for the first section, 170 ℃ for the second section, 165 ℃ for the third section, 160 ℃ for the fourth section, 155 ℃ for the fifth section, and 150 ℃ for the sixth section; and the screw rotating speed is 10 r / min.

[0025] Further, the casting process used in step (3) is direct casting, the casting roller is a chromium-plated steel roller, the thickness of the chromium plating layer is 0.01-0.015 mm, the diameter of the steel roller is 500 mm, the height of the steel roller is 0.20-0.25 mm; the temperature of the steel roller is set to 35-40 DEG C; the pressure winding process is pressure winding on a 60-65A liquid silica gel roller, and the pressure is 5-8 Kgf.

[0026] The MMT with high surface area is modified to obtain OMMT as a carrier, the nano-sized SiO2 is loaded on the OMMT, and then interacts with ZrO2 to obtain ZrO2 / FSi-SiO2@OMMT with good wear resistance and self-cleaning performance. The nano-sized SiO2 is modified by a silane coupling agent to obtain FSi-SiO2 with excellent wear resistance and hydrophobicity, is loaded on the OMMT, and is combined with ZrO2. In this process, PFOTES is added to modify the wear resistance and hydrophobicity of the three materials, and also reduces the surface energy of the materials. The OMMT obtained by the organic modification of hexadecyl trimethyl ammonium bromide (CTAB) and the grafting of PFOTES to the MMT not only provides micron-sized roughness for the wear-resistant and self-cleaning agent, but also improves the dispersibility and compatibility of the agent in the PE resin, thereby greatly improving the wear-resistant and self-cleaning performance of the PE film.

[0027] The application has the following beneficial effects:

[0028] (1) The application loads the nano-sized SiO2 with a small size (10-100 nm) and the zirconium dioxide with a medium size (500-1000 nm) on the micron-sized MMT which is organically modified to obtain a wear-resistant and self-cleaning filler with multiple nano- and micron-sized supermicrostructures. The synergistic effect of the three materials with different sizes increases the roughness of the composite material, and improves the wear resistance and self-cleaning performance of the material.

[0029] (2) The nano-particles used in the application originally have good dispersibility and thermal stability. After being organically modified, the dispersibility and compatibility of the filler in the base resin are further improved, the wear resistance and self-cleaning performance of the composite material are greatly improved, and the heat resistance and mechanical properties of the composite material are also improved. After the micron-sized MMT is modified by CTAB to obtain OMMT, and PFOTES is grafted to the surface of the OMMT, the hydrophobicity and the compatibility with the base material are greatly improved.

[0030] (3) The application combines nano-materials with multiple sizes to obtain an antibacterial and antifouling filler which is low in cost, excellent in performance, non-toxic and non-polluting, and very friendly to the environment, and therefore has excellent application prospects and a wider application range. BRIEF DESCRIPTION OF DRAWINGS

[0031] Figure 1 The Fourier infrared spectrum of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@OMMT.

[0032] Figure 2 The scanning electron microscope image of the OMMT obtained after organic modification and grafting of the micron-sized MMT of Example 1.

[0033] Figure 3 The scanning electron microscope image of the FSi-SiO2 prepared in Example 1 of the application.

[0034] Figure 4 The scanning electron microscope image of the ZrO2 / FSi-SiO2@OMMT prepared in Example 1 of the application. DETAILED DESCRIPTION

[0035] The application will be further described in conjunction with specific examples to make the application easier to understand, but the application is not limited to these examples only.

[0036] Example 1

[0037] The preparation method of the wear-resistant self-cleaning PE film is as follows:

[0038] 1. The specific preparation process of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@OMMT is as follows:

[0039] (1) 3 g of micron-sized (1-10 μm) montmorillonite (MMT) was added to 120 mL of deionized water, stirred at room temperature for 30 minutes, and NaOH solution (0.1 mol / L) was added to adjust the pH of the solution to 12. It was carried out for 3 hours under 80 ℃ water bath and magnetic stirring, 1.9 g of hexadecyl trimethyl ammonium bromide (CTAB) was dissolved in 50 mL of deionized water and then added, and the stirring was continued for 3 hours. The final product was centrifuged and washed with deionized water and ethanol three times, and dried at 60 ℃ for 12 h to obtain OMMT.

[0040] (2) First, 5 mL of tetraethyl orthosilicate (TEOS) was added to a mixed solution of ethanol (50 mL) and ammonia water (5 mL, concentration 28%), and left to stand for 3 h to prepare a SiO2 sol. Then 0.37 g of KH-570 was added to the SiO2 sol, and stirred uniformly at 60 ℃ for 2 h. The product was collected after multiple centrifugations to obtain modified SiO2 particles, which were dried in a 50 ℃ drying oven for 10 h to obtain FSi-SiO2 with a particle size of 10-100 nm.

[0041] (3) 2.30 g of FSi-SiO2 and 1.50 g of ZrO2 (500-1000 nm) were added to a three-necked flask containing 20 mL of deionized water, the pH was adjusted to 3 with hydrochloric acid, and stirring was carried out at 60°C for 30 min. Then 2.50 g of PFOTES (perfluorooctyltriethoxysilane) and 7.50 g of OMMT were added, and refluxing was carried out at 60°C for 13 h. Finally, the mixed solution was dried in a 50°C oven and then ground through a sieve to obtain ZrO2 / FSi-SiO2@OMMT in powder form.

[0042] 2. 2 parts by weight of ZrO2 / FSi-SiO2@OMMT, 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP, and 1 part by weight of polyethylene wax were mixed, and then uniformly mixed with 90 parts by weight of PE particles in a high-speed mixer at a speed of 300 r / min and a temperature of 60°C, and then dried in a 60°C oven for 1 h.

[0043] 3. The dried raw materials were added to a twin-screw extruder, the first, second, third, fourth, fifth, and sixth sections of the extruder were set to 150°C, 170°C, 165°C, 160°C, 155°C, and 150°C, respectively, the screw speed was 10 r / min, and the mixed masterbatch was obtained by extrusion granulation.

[0044] 4. The mixed masterbatch obtained by the twin-screw extruder and the granulator was dried in a 60°C oven for 1 h, and then subjected to extrusion casting, mirror surface lamination, cooling, edge cutting, and pressure winding in a casting machine to obtain a wear-resistant self-cleaning PE film. The casting process was direct casting, the casting roll was a chromium-plated steel roll with a chromium-plated layer thickness of 0.01 mm, a steel roll diameter of 500 mm, and a steel roll center height of 0.20 mm; the steel roll temperature was set to 40°C; and the pressure winding process was pressure winding on a 60 A liquid silicone rubber roll at a pressure of 7 Kgf.

[0045] Figure 1 The Fourier infrared spectrum of ZrO2 / FSi-SiO2@OMMT had a -CH3 stretching vibration peak at 2925 cm -1 , a -CH2 stretching vibration peak at 2854 cm -1 , a -CH2 bending vibration peak at 1470 cm -1 , a Si-O-Si asymmetric stretching vibration absorption peak at 1060 cm -1 , a Si-O-Si symmetric stretching vibration absorption peak at 800 cm -1 , and a peak at 449 cm -1There is Si-O-Si bending vibration absorption peak, which shows that the organic modification of MMT makes CTAB and PFOTES successfully grafted on the surface of OMMT; also shows that FSi-SiO2 is successfully loaded on OMMT. There is a characteristic peak of Zr-O at 654 cm -1

[0046] Figure 2 The scanning electron microscope image of OMMT obtained after the micron-sized MMT of Example 1 is subjected to organic modification and grafting. It can be seen that the surface of OMMT is in a lamellar structure, the surface is smooth and clear, the layers are stacked with each other, and the lamellar structure is dispersed.

[0047] Figure 3 The scanning electron microscope image of FSi-SiO2. It can be seen from the figure that the size of FSi-SiO2 is relatively small.

[0048] Figure 4 The scanning electron microscope image of ZrO2 / FSi-SiO2@OMMT. It can be seen that small-sized FSi-SiO2 is attached to OMMT, and then combined with large particles of medium-sized ZrO2.

[0049] Example 2

[0050] The preparation method of the wear-resistant and self-cleaning PE film is as follows:

[0051] 1. The preparation process of the wear-resistant and self-cleaning agent ZrO2 / FSi-SiO2@OMMT is the same as that of Example 1.

[0052] 2. 3 parts by weight of FSi-SiO2 / ZrO2@OMMT, 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP, and 1 part by weight of polyethylene wax are mixed, and then uniformly mixed with 90 parts by weight of PE particles in a high-speed mixer. The rotation speed of the high-speed mixer is 300 r / min, and the temperature is 60℃. Then, the mixture is placed in a 60℃ oven for drying for 1 hour.

[0053] 3. The dried raw materials are added to a twin-screw extruder, and the first, second, third, fourth, fifth and sixth sections of the twin-screw extruder are set to 150℃, 170℃, 165℃, 160℃, 155℃ and 150℃ respectively. The rotation speed of the screw is 10 r / min. The mixed master batch is obtained by extrusion granulation.

[0054] ​4. The mixed master batch obtained by the twin-screw extruder and the granulator is dried in an oven at 60°C for 1 hour, and then added to a casting machine to go through extrusion casting, mirror surface lamination, cooling, edge cutting, and pressure winding to obtain the wear-resistant self-cleaning PE film. The casting process is direct casting, the casting roller is a chromium-plated steel roller, the thickness of the chromium-plated layer is 0.01 mm, the diameter of the steel roller is 500 mm, and the middle height of the steel roller is 0.20 mm; the temperature of the steel roller is set to 40°C; and the pressure winding process is pressure winding on a 60A liquid silica gel roller with a pressure of 7 Kgf.

[0055] Example 3

[0056] The preparation method of the wear-resistant self-cleaning PE film is specifically as follows:

[0057] 1. The preparation process of the wear-resistant self-cleaning agent FSi-SiO2 / ZrO2@OMMT is the same as that in Example 1.

[0058] 2. 4 parts by weight of ZrO2 / FSi-SiO2@OMMT, 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP, and 1 part by weight of polyethylene wax are mixed, and then uniformly mixed with 90 parts by weight of PE particles in a high-speed mixer at a speed of 300 r / min and a temperature of 60°C, and then dried in an oven at 60°C for 1 hour.

[0059] 3. The dried raw materials are added to a twin-screw extruder, the first, second, third, fourth, fifth, and sixth sections of the twin-screw extruder are set to 150°C, 170°C, 165°C, 160°C, 155°C, and 150°C respectively, the rotation speed of the screw is 10 r / min, and mixed master batch is obtained by extrusion granulation.

[0060] 4. The mixed master batch obtained by the twin-screw extruder and the granulator is dried in an oven at 60°C for 1 hour, and then added to a casting machine to go through extrusion casting, mirror surface lamination, cooling, edge cutting, and pressure winding to obtain the wear-resistant self-cleaning PE film. The casting process is direct casting, the casting roller is a chromium-plated steel roller, the thickness of the chromium-plated layer is 0.01 mm, the diameter of the steel roller is 500 mm, and the middle height of the steel roller is 0.20 mm; the temperature of the steel roller is set to 40°C; and the pressure winding process is pressure winding on a 60A liquid silica gel roller with a pressure of 7 Kgf.

[0061] Example 4

[0062] The preparation method of the wear-resistant self-cleaning PE film is specifically as follows:

[0063] 1. The preparation process of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@OMMT is the same as that in Example 1.

[0064] 2. 5 parts by weight of ZrO2 / FSi-SiO2@OMMT and 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP, 1 part by weight of polyethylene wax were mixed, and then mixed with 90 parts by weight of PE particles in a high-speed mixer, the rotating speed of the high-speed mixer was 300 r / min, the temperature was 60℃, and then placed in a 60℃ oven for drying for 1 hour.

[0065] 3. The dried raw materials were added to a twin-screw extruder, the first section temperature of the twin-screw extruder was 150℃, the second section temperature was 170℃, the third section temperature was 165℃, the fourth section temperature was 160℃, the fifth section temperature was 155℃, and the sixth section temperature was 150℃; the rotating speed of the screw was 10 r / min; and the mixed master batch was obtained by extrusion granulation.

[0066] 4. The mixed master batch obtained by the twin-screw extruder and the granulator was dried in a 60℃ oven for 1 hour, and then added to a casting machine to obtain a wear-resistant self-cleaning PE film by extrusion casting, mirror surface pressing, cooling, edge cutting, and pressure winding. The casting process was direct casting, the casting roller was a chromium-plated steel roller, the thickness of the chromium-plated layer was 0.01 mm, the diameter of the steel roller was 500 mm, the center height of the steel roller was 0.20 mm; the temperature of the steel roller was set to 40℃; and the pressure winding process was pressure winding on a 60 A liquid silicone rubber roller with a pressure of 7 Kgf.

[0067] Comparative Example 1

[0068] 1. 90 parts by weight of LLDPE particles were mixed with 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP, and 1 part by weight of polyethylene wax in a high-speed mixer, the rotating speed of the high-speed mixer was 300 r / min, the temperature was 60℃, and then placed in a 60℃ oven for drying for 1 hour.

[0069] 2. The dried raw materials were added to a twin-screw extruder, the first section temperature of the twin-screw extruder was 180℃, the second section temperature was 175℃, the third section temperature was 170℃, the fourth section temperature was 165℃, and the fifth section temperature was 160℃; the rotating speed of the screw was 10 r / min; and the mixed master batch was obtained by extrusion granulation.

[0070] 3. The mixed master batch obtained by twin-screw extruder and granulator is dried in an oven at 60°C for 1 hour, and then added into a casting machine to obtain the wear-resistant self-cleaning PE film through extrusion casting, mirror surface pressing, cooling, edge cutting and pressure winding. The casting process is direct casting, the casting roller is a chromium-plated steel roller, the thickness of the chromium-plated layer is 0.01 mm, the diameter of the steel roller is 500 mm, and the center height of the steel roller is 0.20 mm; the temperature of the steel roller is set to 40°C; and the pressure winding process is pressure winding on a 60A liquid silica gel roller with a pressure of 7 Kgf.

[0071] Comparative Example 2

[0072] The preparation method of the wear-resistant self-cleaning PE film is as follows:

[0073] 1. The specific preparation process of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@MMT is as follows:

[0074] (1) 5 mL of TEOS is added to a mixed solution of ethanol (50 mL) and ammonia water (5 mL, concentration of 28%), and left to stand for 3 h to prepare a SiO2 sol. Then 0.37 g of KH-570 is added to the SiO2 sol, and after uniform stirring at 60°C for 2 h, the product is centrifuged multiple times to collect the modified SiO2 particles, which are dried in a 50°C drying oven for 10 h to obtain FSi-SiO2 with a particle size of 10-100 nm.

[0075] (2) 2.30 g of FSi-SiO2 and 1.50 g of ZrO2 (500-1000 nm) are added to a three-necked flask containing 20 mL of deionized water, and the pH is adjusted to 3 with hydrochloric acid, and stirred at 60°C for 30 min. Then 2.50 g of PFOTES and 7.50 g of MMT are added, and refluxed at 60°C for 13 h. Finally, the mixed solution is dried in a 50°C oven and ground through a sieve to obtain a powder of ZrO2 / FSi-SiO2@MMT

[0076] 2. 4 parts by weight of ZrO2 / FSi-SiO2@MMT, 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP and 1 part by weight of polyethylene wax are mixed, and then uniformly mixed with 90 parts by weight of PE particles in a high-speed mixer at a speed of 300 r / min and a temperature of 60°C, and then dried in a 60°C oven for 1 hour.

[0077] 3. The dried raw materials are added to a twin-screw extruder, the first section of which has a temperature of 150°C, the second section has a temperature of 170°C, the third section has a temperature of 165°C, the fourth section has a temperature of 160°C, the fifth section has a temperature of 155°C, and the sixth section has a temperature of 150°C; the screw speed is 10 r / min; and the mixed masterbatch is obtained by extrusion granulation.

[0078] 4. The mixed masterbatch obtained by the twin-screw extruder and the granulator is dried in an oven at 60°C for 1 hour, and then added to a casting machine to undergo extrusion casting, mirror surface lamination, cooling, edge cutting, and pressure winding, thereby obtaining the wear-resistant self-cleaning PE film. The casting process is direct casting, the casting roller is a chromium-plated steel roller, the thickness of the chromium plating layer is 0.01 mm, the diameter of the steel roller is 500 mm, and the center height of the steel roller is 0.20 mm; the temperature of the steel roller is set to 40°C; and the pressure winding process is pressure winding on a 60 A liquid silica gel roller with a pressure of 7 Kgf.

[0079] Comparative Example 3

[0080] The preparation method of the wear-resistant self-cleaning PE film is as follows:

[0081] 1. The specific preparation process of the wear-resistant self-cleaning agent FSi-SiO2@OMMT is as follows:

[0082] (1) 3 g of micron-sized MMT is added to 120 mL of deionized water, stirred at room temperature for 30 minutes, and then NaOH solution (0.1 mol / L) is added to adjust the pH of the solution to 12. The solution is stirred under a water bath at 80°C and a magnetic stirrer for 3 hours. 1.9 g of CTAB is dissolved in 50 mL of deionized water and then added. The stirring is continued for 3 hours. The final product is centrifuged and washed with deionized water and ethanol three times. After drying at 60°C for 12 h, OMMT is obtained.

[0083] (2) First, 5 ml of TEOS is added to a mixed solution of ethanol (50 ml) and ammonia water (5 ml, concentration 28%), and left to stand for 3 h to prepare a SiO2sol. Then, 0.37 g of KH-570 is added to the SiO2sol, and the mixture is uniformly stirred at 60°C for 2 h. The product is collected after multiple centrifugations to obtain modified SiO2particles. After drying at 50°C for 10 h, FSi-SiO2with a particle size of 10-100 nm is obtained.

[0084] (3) 2.30 g FSi-SiO2 was added into a three-necked flask containing 20 mL of deionized water, and the pH was adjusted to 3 with hydrochloric acid, and stirred at 60 ℃ for 30 min, then 2.50 g of PFOTES and 7.50 g of OMMT were added, and refluxed at 60 ℃ for 13 h. Finally, the mixed solution was dried in an oven at 50 ℃, and then ground through a sieve to obtain a powder of FSi-SiO2@OMMT.

[0085] 2. 4 parts by weight of FSi-SiO2@OMMT, 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP, and 1 part by weight of polyethylene wax were mixed, and then uniformly mixed with 90 parts by weight of PE particles in a high-speed mixer at a speed of 300 r / min and a temperature of 60 ℃, and then placed in a 60 ℃ oven for drying for 1 h.

[0086] 3. The dried raw materials were added to a twin-screw extruder, and the first, second, third, fourth, fifth, and sixth sections of the extruder were set to 150 ℃, 170 ℃, 165 ℃, 160 ℃, 155 ℃, and 150 ℃, respectively, and the screw speed was 10 r / min; the mixed masterbatch was obtained by extrusion granulation.

[0087] 4. The mixed masterbatch obtained by the twin-screw extruder and the granulator was dried in a 60 ℃ oven for 1 h, and then extrusion casting, mirror surface pressing, cooling, edge cutting, and pressure winding were performed in a casting machine to obtain the wear-resistant self-cleaning PE film. The casting process was direct casting, the casting roll was a chromium-plated steel roll with a chromium-plated layer thickness of 0.01 mm, a steel roll diameter of 500 mm, and a steel roll center height of 0.20 mm; the steel roll temperature was set to 40 ℃; and the pressure winding process was pressure winding on a 60 A liquid silicone rubber roll with a pressure of 7 Kgf.

[0088] Comparative Example 4

[0089] The preparation method of the wear-resistant self-cleaning PE film is as follows:

[0090] 1. The specific preparation process of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2 and OMMT is as follows:

[0091] (1) 3 g of micron-sized (1-10 μm) MMT was added to 120 mL of deionized water, stirred at room temperature for 30 min, and NaOH solution (0.1 mol / L) was added to adjust the pH of the solution to 12, and stirred at 80 ℃ water bath and magnetic stirring for 3 h, then 1.9 g of CTAB was dissolved in 50 mL of deionized water and added, and stirred for another 3 h. The final product was centrifuged and washed with deionized water and ethanol three times, and dried at 60 ℃ for 12 h to obtain OMMT.

[0092] (2) First, 5 mL of TEOS was added to a mixed solution of ethanol (50 mL) and ammonia water (5 mL, concentration of 28%), and left to stand for 3 h to prepare a SiO2sol. Then, 0.37 g of KH-570 was added to the SiO2sol, and after uniform stirring at 60°C for 2 h, the product was collected by centrifugation multiple times to obtain modified SiO2particles, which were dried in a 50°C drying oven for 10 h to obtain FSi-SiO2with a particle size of 10-100 nm.

[0093] 2. 2 parts by weight of ZrO2 / FSi-SiO2, 2 parts by weight of OMMT, 0.5 parts by weight of antioxidant 1010, 0.5 parts by weight of antioxidant DLTP, and 1 part by weight of polyethylene wax were mixed, and then mixed with 90 parts by weight of PE particles in a high-speed mixer at a speed of 300 r / min and a temperature of 60°C, and then dried in a 60°C oven for 1 h.

[0094] 3. The dried raw materials were added to a twin-screw extruder, and the first, second, third, fourth, fifth, and sixth sections of the twin-screw extruder were set to 150°C, 170°C, 165°C, 160°C, 155°C, and 150°C, respectively, and the screw speed was 10 r / min; the mixed masterbatch was obtained by extrusion granulation.

[0095] 4. The mixed masterbatch obtained by the twin-screw extruder and the granulator was dried in a 60°C oven for 1 h, and then fed into a casting machine to perform extrusion casting, mirror surface lamination, cooling, edge cutting, and pressure winding to obtain the wear-resistant self-cleaning PE film. The casting process was direct casting, the casting roller was a chromium-plated steel roller with a chromium-plated layer thickness of 0.01 mm, a steel roller diameter of 500 mm, and a steel roller center height of 0.20 mm; the steel roller temperature was set to 40°C; and the pressure winding process was pressure winding on a 60 A liquid silicone rubber roller with a pressure of 7 Kgf.

[0096] The wear-resistant self-cleaning PE films obtained in Examples 1-4 and Comparative Examples 1-4 were subjected to mechanical testing, and the test results are shown in Table 1.

[0097] Table 1 Mechanical property test results

[0098]

[0099] Table 1 is the mechanical property test results of each example and each comparative example. From the above performance test results, it can be clearly seen that the tensile strength of the PE film of Examples 1-4 increases first and then slightly decreases with the increase of the amount of wear-resistant self-cleaning filler, while the longitudinal elongation at break and the transverse angle tear strength are always increasing, indicating that the mechanical properties of the PE film are improved with the addition of the filler. When the amount of wear-resistant self-cleaning agent reaches 5 parts (Example 4), the tensile strength slightly decreases, and the elongation in the transverse direction and the angle tear strength in the longitudinal direction also decrease compared with Example 3. It is possible that the wear-resistant self-cleaning agent is added too much, which causes agglomeration in the matrix material, resulting in a decrease in mechanical properties. According to Comparative Examples 1-4, the PE film has less improvement after adding the filler without organic modification, and the elongation even decreases. Although the performance of the nano material without loading also improves, the improvement is not as good as that after loading. The reason is that the nano material without loading agglomerates, which limits the performance improvement.

[0100] Table 2 Wear resistance and self-cleaning property of the film

[0101]

[0102] As shown in Table 2, the addition of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@OMMT significantly improves the wear resistance and self-cleaning property of the film. With the increase of the amount of wear-resistant self-cleaning filler, the wear resistance of the film of Examples 1-4 is always improved, while the self-cleaning property is first increased and then decreased. The continuous improvement of wear resistance is due to the addition of modified ZrO2, and the decrease of self-cleaning property after the increase is due to the same reason as the mechanical properties, that is, the performance of the agglomerated material cannot be fully utilized. As can be seen from the comparison between Example 3 and Comparative Example 2, the compatibility of unmodified MMT in the resin material is poorer than that of OMMT, which therefore affects the performance of the polyethylene film. As can be seen from the comparison between Example 3 and Comparative Example 4, compared with the addition of ZrO2 / FSi-SiO2+ OMMT separately, the loading of ZrO2 / FSi-SiO2 on OMMT can improve the compatibility and dispersibility of ZrO2 / FSi-SiO2 with the base resin to a certain extent, thereby improving the wear resistance and self-cleaning property of the polyethylene film. As can also be seen from the comparison between Example 3 and Comparative Example 3, the addition of ZrO2 improves the wear resistance of the polyethylene film.

[0103] The above description is only the preferred embodiment of the present application, and any equivalent changes and modifications made within the scope of the patent application of the present application shall be included in the scope of the present application.

Claims

1. A wear-resistant, self-cleaning polyethylene film, characterized in that: The polyethylene film comprises the following raw materials by weight fraction: 90 LLDPEs; 2-5 parts of abrasion-resistant self-cleaning agent; Antioxidant 1010: 0.5-1 part; 1-3 parts of polyethylene wax; Antioxidant DLTP 0.5-1 part; The wear-resistant self-cleaning agent is ZrO2 / FSi-SiO2@OMMT; The preparation method of the wear-resistant self-cleaning agent ZrO2 / FSi-SiO2@OMMT includes the following steps: (1) Preparation of OMMT: 3g of micron-sized montmorillonite was added to 120 mL of deionized water and stirred at room temperature for 30 minutes. 0.1mol / L NaOH solution was added to adjust the pH of the solution to 12 and stirred at 80 °C for 3 hours. 1.9g of hexadecyltrimethylammonium bromide was dissolved in 50 mL of deionized water and added to the above solution and stirred for 3 hours. After the reaction was completed, OMMT was obtained by centrifugation, washing and drying. (2) Preparation of FSi-SiO2: First, 5 mL of tetraethyl orthosilicate was added to a mixed solution of ethanol and ammonia, and the solution was allowed to stand for 3 h to obtain SiO2 sol; 0.37 g of KH-570 was added to the SiO2 sol, and the mixture was stirred evenly at 60 °C for 2 h. After the reaction was completed, the mixture was centrifuged and dried to obtain FSi-SiO2. (3) Preparation of ZrO2 / FSi-SiO2@OMMT: 2.30g FSi-SiO2 and 1.50g ZrO2 were added to 20mL of deionized water, and the pH of the solution was adjusted to 3 with hydrochloric acid. The mixture was stirred at 60℃ for 30 min. Then 2.50g perfluorooctyltriethoxysilane and 7.50g OMMT were added, and the mixture was refluxed at 60℃ for 13 h. After the reaction was completed, the resulting solution was dried at 50℃, ground and sieved to obtain powdered ZrO2 / FSi-SiO2@OMMT.

2. The polyethylene film according to claim 1, characterized in that: In step (2), the volume ratio of ethanol to ammonia is 10:

1.

3. A method for preparing the wear-resistant, self-cleaning polyethylene film as described in claim 1, characterized in that: Includes the following steps: (1) After the wear-resistant self-cleaning agent, antioxidant 1010, antioxidant DLTP and polyethylene wax are mixed evenly, they are added to a high-speed mixer and mixed evenly with LLDPE particles, and then dried at 60℃ for 1h. (2) The dried material is added to a twin-screw extruder and extruded and granulated to obtain masterbatch; (3) The obtained masterbatch is dried and then added to a casting machine for extrusion casting, mirror pressing, cooling, edge trimming, and pressure winding to obtain wear-resistant self-cleaning PE film.

4. The preparation method according to claim 3, characterized in that: The high-speed mixer mentioned in step (1) has a rotation speed of 300 r / min and a temperature of 60℃.

5. The preparation method according to claim 3, characterized in that: The extrusion temperatures of the twin-screw extruder used in step (2) are: 150℃ for the first section, 170℃ for the second section, 165℃ for the third section, 160℃ for the fourth section, 155℃ for the fifth section, and 150℃ for the sixth section; the screw speed is 10 r / min.

6. The preparation method according to claim 3, characterized in that: The casting process used in step (3) is direct casting. The casting roller is a chrome-plated steel roller with a chrome plating layer thickness of 0.01~0.015mm, a roller diameter of 500mm, and a roller height of 0.20~0.25mm. The roller temperature is set to 35~40℃. The pressure winding process is to apply pressure to a 6065A liquid silicone roller and the pressure is 5~8Kgf.

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