Anti-static film for containing water-based material and preparation method of anti-static film

Abstract

The invention relates to the technical field of packaging films, and particularly discloses an anti-static film for containing a water-based material and a preparation method of the anti-static film. The invention discloses an anti-static film for containing a water-based material. The anti-static film comprises an inner layer, a middle layer and an outer layer which are obtained by co-extruding three layers, the inner layer is prepared from the following raw materials in parts by weight: 40-50 parts of low-density polyethylene, 40-50 parts of 8-carbon metallocene low-density polyethylene and 2-3 parts of antistatic master batch; the middle layer is prepared from the following raw materials in parts by weight: 55-65 parts of low-density polyethylene, 35-45 parts of 8-carbon metallocene low-density polyethylene and 2-3 parts of antistatic master batch; the outer layer is prepared from the following raw materials in parts by weight: 30-40 parts of low-density polyethylene, 55-65 parts of 8-carbon metallocene low-density polyethylene and 2-3 parts of antistatic master batch. The anti-static film containing the water-based material can well bear various stresses in the transportation process in the transportation and daily use process, and is not prone to being damaged.

Description

Technical Field

[0001] The present application relates to the technical field of packaging films, and more specifically, to an antistatic film for containing aqueous materials and a preparation method thereof. Background Art

[0002] Metal chemical barrels are containers used to store and transport chemicals, usually made of metal materials. This type of barrel has good corrosion resistance and sealing properties, which can ensure the safety and stability of chemicals during storage and transportation. Metal chemical barrels are widely used in chemical, pharmaceutical, pesticide, dye and other industries, and are indispensable logistics packaging containers in these industries.

[0003] According to the specific use requirements and the properties of chemicals, metal chemical barrels can be designed into different specifications and shapes to meet the use requirements of different occasions; however, after the raw materials in the chemical barrels are used up, they need to be treated as hazardous waste in accordance with environmental protection requirements, which will incur additional costs. Therefore, in the field of chemical barrel packaging, the chemical raw materials are packaged in a chemical barrel + liner bag structure. A layer of liner bag is set in the metal chemical barrel. The liner bag is separated between the raw materials and the barrel body. The metal chemical barrel does not directly contact the chemical raw materials, and the liner bag can effectively keep the chemical raw materials clean and effectively isolate the external environment from the impact of the chemical raw materials. When treating hazardous waste, you only need to take out the liner bag for treatment. The liner bag is very light, and the treatment cost is much lower than that of metal chemical barrels. At the same time, the metal chemical barrel can be directly recycled and reused, which helps to effectively reduce costs.

[0004] With respect to the above-mentioned related technologies, the inventors believe that the above-mentioned chemical barrels containing chemical raw materials and with liner bags will inevitably be subjected to the adverse effects of bumps during long-distance transportation. At this time, not only the liner bags are required to have certain anti-static properties, but also the liner bags need to be protected from damage. However, the materials of existing liner bags are often unable to withstand the various stresses during transportation, resulting in a high scrap rate, which makes it difficult to meet long-term needs during use.

[0005] Therefore, it is urgent to propose a solution to solve the above technical problems. Summary of the invention

[0006] In order to prevent the inner liner bags containing chemical raw materials in chemical barrels from being damaged during transportation and daily use, the present application provides an antistatic film for containing aqueous materials and a preparation method thereof.

[0007] In a first aspect, the present application provides an antistatic film for holding water-based materials, which adopts the following technical solution: An antistatic film for holding water-based materials, comprising an inner layer, a middle layer and an outer layer structure obtained by three-layer co-extrusion; The inner layer is made of the following raw materials in parts by weight: 40-50 parts of low density polyethylene; 40-50 parts of 8-carbon metallocene low-density polyethylene; 2-3 copies of antistatic masterbatch; The middle layer is made of the following raw materials in parts by weight: 55-65 parts of low density polyethylene; 8-carbon metallocene low-density polyethylene 35-45 parts; 2-3 copies of antistatic masterbatch; The outer layer is made of the following raw materials in parts by weight: 30-40 parts of low density polyethylene; 8-carbon metallocene low-density polyethylene 55-65 parts; 2-3 copies of antistatic masterbatch.

[0008] By adopting the above technical scheme, low-density polyethylene has good chemical stability, can resist alkali and most organic solvents, and has good flexibility and processing performance, so it is used as one of the main raw materials for the inner layer, middle layer and outer layer. 8-carbon metallocene low-density polyethylene is a polyethylene resin synthesized using metallocene catalysts. Compared with traditional polyethylene, it has greater elongation at break and better impact strength. The molecular weight of 8-carbon metallocene low-density polyethylene is large and tightly distributed, and the melting speed is fast. It is also easy to control during processing, but its cost is relatively high. Therefore, it is used in combination with ordinary low-density polyethylene, which can not only meet the needs of the liner bag not being easily damaged during transportation and daily use, but also effectively control costs. The use of antistatic masterbatch can effectively prevent static electricity accumulation and bring about the excellent effect of improving processing performance and extending service life. At the same time, the inner layer, middle layer and outer layer structure obtained by three-layer co-extrusion are used as antistatic film. By adjusting the combined amount of low-density polyethylene and 8-carbon metallocene low-density polyethylene, inner layer, middle layer and outer layer structures with different characteristics can be obtained, so that the antistatic film has better adaptability to contact with chemical raw materials and metal chemical barrels after application, and the overall practical application effect is more significant.

[0009] Preferably, the thickness of the inner layer is 20-30 μm; the thickness of the middle layer is 140-160 μm; and the thickness of the outer layer is 20-30 μm.

[0010] By adopting the above technical scheme, when the antistatic film formed by the inner layer, middle layer and outer layer of the above thickness is used, the inner layer contacts the chemical raw materials, and the outer layer contacts the metal chemical barrel. The overall thinness helps to improve flexibility and flexibility; the middle layer connects the inner layer and the outer layer and plays a transitional role, which can provide better support and strength; the three layers cooperate with each other to better withstand various stresses during transportation and daily use, and are not prone to damage; at the same time, the reasonable optimization distribution of the thickness of each layer can also make full use of the different characteristics of the inner layer, the middle layer and the outer layer, which helps to reduce costs.

[0011] Preferably, 3-5 parts by weight of polyamide fiber are added to the raw materials of the inner layer and the outer layer, and 4-6 parts by weight of sepiolite fiber are added to the raw materials of the middle layer.

[0012] By adopting the above technical solutions, polyamide fiber has extremely high wear resistance, which enables it to withstand frequent friction and wear in the liner bag; it also has high strength and toughness, can withstand large tension and pressure; and has good resistance to a variety of chemicals, and can remain stable in various chemical environments; therefore, the application of polyamide fiber to the inner and outer layers can significantly improve the breakage resistance while meeting the requirements of flexibility and flexibility. Sepiolite fiber has a unique chain and layered combined structure, and there are a large number of nano-scale micropores and mesopores in its clustered fibers, which can be randomly dispersed in the middle layer, playing a "skeleton" support role, thereby enhancing the support and strength of the middle layer, significantly improving the ability of the antistatic film to withstand various stresses and making it more resistant to breakage. At the same time, in the process of co-extrusion of the inner layer, the middle layer and the outer layer, at the interface between the middle layer and the inner layer and the outer layer, the larger specific surface area and porous adsorption of the sepiolite fiber are utilized, and the nano-penetration effect of the polyamide fiber is used to form a entangled structure of the sepiolite fiber and the polyamide fiber, which can improve the overall structural toughness of the antistatic film, and when subjected to various stresses, it has better interlayer stress conduction and structural stability, thereby making the antistatic film less likely to be damaged during transportation and daily use.

[0013] Preferably, the polyamide fiber has a diameter of 300-500 nm and a length of 3-6 mm.

[0014] Preferably, the diameter of the sepiolite fiber is 5-10 μm and the length is 4-6 mm.

[0015] By adopting the above technical scheme, the polyamide fibers and sepiolite fibers of the above specifications can be evenly dispersed and form a relatively tight network structure when used, thereby bringing better application effects; at the same time, at the interface between the middle layer and the inner layer and the outer layer, the bond between the sepiolite fibers and the polyamide fibers is also relatively tight and stable, thereby making the final antistatic film have better quality and damage resistance.

[0016] Preferably, the polyamide fiber is subjected to modification treatment before use, and the specific modification treatment operation is as follows: The polyamide fiber raw material is dispersed in water, hexadecyltrimethylammonium bromide is added, the mixture is heated and stirred, and then filtered, washed and dried to obtain the modified polyamide fiber.

[0017] By adopting the above technical scheme, the modified polyamide fiber is obtained by organically modifying the surface of the polyamide fiber. The modified polyamide fiber has stronger dispersibility when used in the inner layer and the outer layer, and can form a denser and more stable bonding state with the sepiolite fiber at the interface between the middle layer and the inner layer and the outer layer. The corresponding effect exerted can also be significantly enhanced, and finally an antistatic film with better damage resistance is obtained.

[0018] Preferably, 1-3 parts by weight of a functional additive are added to the raw materials of the middle layer, and the functional additive is composed of attapulgite powder and lanthanum oxide, and the weight ratio of the attapulgite powder to lanthanum oxide is (6-10):1.

[0019] By adopting the above technical solution, attapulgite is a natural nano-scale hydrated magnesium-aluminum silicate clay mineral with a high specific surface area and high adsorption due to its internal honeycomb pore structure. After application, it can not only improve the tensile strength and tear strength of the middle layer, but also bring a synergistic enhancement effect to the sepiolite fiber, making the interface between the middle layer and the inner layer and the outer layer more stable, and the interlayer stress conduction performance is also better, thereby significantly improving the damage resistance of the antistatic film. Lanthanum oxide can not only enhance the mechanical properties of polyethylene, such as improving strength, hardness and toughness, but also play an interfacial modification role on sepiolite fibers, making the mosaicity of sepiolite fibers and polyamide fibers better, bringing further improvement in the damage resistance of the antistatic film. At the same time, when the functional additives composed of attapulgite powder and lanthanum oxide are used in combination, the two can play an excellent compounding and synergistic role with each other, forming a mixed load by relying on the pore structure on the surface of sepiolite fiber, and bringing a mixed improvement and enhancement effect when the sepiolite fiber and polyamide fiber are embedded, ultimately making the anti-static film's resistance to damage when subjected to various stresses during transportation and daily use significantly improved.

[0020] Preferably, the weight ratio of the attapulgite powder to lanthanum oxide is 8:1.

[0021] By adopting the above technical solution, the attapulgite powder and lanthanum oxide in the above weight ratio cooperate with each other to achieve better corresponding effects when used, so that the antistatic film for containing water-based materials performs better in improving the damage resistance.

[0022] In a second aspect, the present application provides a method for preparing an antistatic film for holding an aqueous material, using the following technical solution: A method for preparing an antistatic film for holding water-based materials comprises the following steps: (1) preparing raw materials required for preparing the inner layer, the middle layer and the outer layer according to the proportion; (2) The raw materials required for preparing the inner layer, the middle layer and the outer layer are mixed respectively, melt-kneaded respectively, and then a sheet is obtained by three-layer co-extrusion using an extruder; (3) Preheating the sheet obtained in step (2) and then stretching and shaping it to obtain an antistatic film for containing water-based materials.

[0023] By adopting the above technical scheme, the raw materials required for preparing the inner layer, the middle layer and the outer layer are mixed and then a multi-layer co-extrusion method is used to obtain a sheet, which is then further stretched and shaped to finally obtain an antistatic film for holding water-based materials. The overall operation in the process is relatively simple and efficient, and the matching performance of each raw material is fully utilized, ensuring the uniformity and high quality of the product, which is also in line with large-scale industrial and efficient production as a whole.

[0024] Preferably, in step (2), the melting and mixing temperature of the inner layer, the middle layer and the outer layer is 150-160°C, and the extrusion temperature in the extruder is 170-200°C.

[0025] By adopting the above technical scheme and setting the above melt mixing temperature, the raw materials required for the preparation of the coating layer can be fully mixed and combined, and at the above extrusion temperature, a uniform and stable structure can be formed, and the layers are tightly combined, ultimately obtaining an antistatic film of excellent quality and stable for containing water-based materials.

[0026] In summary, this application has the following beneficial effects: 1. This application uses 8-carbon metallocene low-density polyethylene in combination with ordinary low-density polyethylene, which can not only meet the requirement that the liner bag is not easily damaged during transportation and daily use, but also effectively control the cost. The raw materials of the inner layer, middle layer and outer layer are composed of different materials, and the obtained inner layer, middle layer and outer layer have different structural characteristics, which can have better adaptability to contact with chemical raw materials and metal chemical barrels after application; 2. The present application adds polyamide fiber to the raw materials of the inner layer and the outer layer, and adds sepiolite fiber to the raw materials of the middle layer, and forms a winding structure of sepiolite fiber and polyamide fiber embedded and extruded at the interface between the middle layer and the inner layer and the outer layer, which brings about better interlayer stress conduction and structural stability, thereby making the antistatic film less likely to be damaged during transportation and daily use; 3. This application adds and uses functional additives composed of attapulgite powder and lanthanum oxide, which form a mixed load by relying on the pore structure on the surface of sepiolite fiber and exert an excellent compounding and synergistic effect, which can significantly improve and enhance the interfacial bonding state between sepiolite fiber and polyamide fiber, and ultimately enable the anti-static film to significantly improve its resistance to damage when subjected to various stresses during transportation and daily use. DETAILED DESCRIPTION

[0027] The present application is further described in detail below in conjunction with embodiments and comparative examples.

[0028] Unless otherwise specified, the raw materials used in the embodiments and comparative examples of the present application are commercially available.

[0029] Low-density polyethylene was purchased from Qatar Petrochemical as Q2018H, film grade; 8-carbon metallocene low-density polyethylene was purchased from Dow Bond metallocene linear low-density polyethylene AT6101; The antistatic masterbatch was purchased from Arkema PEBA5513 antistatic masterbatch from France; The polyamide fiber is polyamide 6 (PA6) nanofiber; Sepiolite fibers were purchased from Dongfeng Mineral Processing Plant in Lingshou County; Attapulgite powder was purchased from Dongfeng Mineral Processing Plant in Lingshou County with a specification of 325 mesh. Example

[0030] Example 1 An antistatic film for holding water-based materials, comprising an inner layer, a middle layer and an outer layer structure obtained by three-layer co-extrusion, the raw materials required for preparing the inner layer and their corresponding weights are shown in Table 1, the raw materials required for preparing the middle layer and their corresponding weights are shown in Table 2, and the raw materials required for preparing the outer layer and their corresponding weights are shown in Table 3, and the film is prepared by the following steps: (1) preparing raw materials required for preparing the inner layer, the middle layer and the outer layer according to the proportion; (2) The raw materials required for preparing the inner layer, the middle layer and the outer layer are mixed respectively, melt-kneaded respectively, and then a sheet is obtained by three-layer co-extrusion using an extruder; (3) Preheating the sheet obtained in step (2) and then stretching and shaping it to obtain an antistatic film for containing water-based materials.

[0031] Note: In the above operation, in step (2), the melting and kneading temperature of the inner layer, the middle layer and the outer layer is 155°C, and the extrusion temperature in the extruder is 185°C. The thickness of the inner layer is 25 μm; the thickness of the middle layer is 150 μm; and the thickness of the outer layer is 25 μm.

[0032] Example 2-3 An antistatic film for holding water-based materials, which is different from Example 1 in that the raw materials required for preparing the inner layer and their corresponding weights are shown in Table 1.

[0033] Table 1 Raw materials and their weight portions (kg / portion) required for the preparation of the inner layer of Examples 1-3 Embodiment 4-5 An antistatic film for holding aqueous materials, which is different from Example 1 in that the raw materials required for preparing the middle layer and their corresponding weights are shown in Table 2.

[0034] Table 2 Raw materials and weight portions (kg / portion) required for the preparation of the middle layer of Examples 1, 4-5 Embodiment 6-7 An antistatic film for holding aqueous materials, which is different from Example 1 in that the raw materials required for preparing the outer layer and their corresponding weights are shown in Table 3.

[0035] Table 3 Raw materials and their weight portions (kg / portion) required for the preparation of the outer layer of Examples 1, 6-7 Example 8 An antistatic film for containing water-based materials, which is different from Example 1 in that in step (2), the melting and kneading temperature of the inner layer, the middle layer and the outer layer is 150°C, and the extrusion temperature in the extruder is 170°C.

[0036] Example 9 An antistatic film for containing water-based materials, which is different from Example 1 in that in step (2), the melting and kneading temperature of the inner layer, the middle layer and the outer layer is 160°C, and the extrusion temperature in the extruder is 200°C.

[0037] Example 10 An antistatic film for holding water-based materials, which is different from Example 1 in that the thickness of the inner layer is 20 μm; the thickness of the middle layer is 160 μm; and the thickness of the outer layer is 20 μm.

[0038] Embodiment 11 An antistatic film for holding water-based materials, which is different from Example 1 in that the thickness of the inner layer is 30 μm; the thickness of the middle layer is 140 μm; and the thickness of the outer layer is 30 μm.

[0039] Example 12 An antistatic film for holding water-based materials, which is different from Example 1 in that 4 parts by weight of polyamide fiber are added to the raw materials of the inner layer and the outer layer, and 5 parts by weight of sepiolite fiber are added to the raw materials of the middle layer. The diameter of the polyamide fiber is 400 nm and the length is 4.5 mm. The diameter of the sepiolite fiber is 7.5 μm and the length is 5 mm.

[0040] Embodiment 13 An antistatic film for containing aqueous materials, which is different from Example 12 in that 5 parts by weight of polyamide fiber are added to the raw materials of the inner layer and the outer layer, and 6 parts by weight of sepiolite fiber are added to the raw materials of the middle layer.

[0041] Embodiment 14 An antistatic film for holding aqueous materials, which is different from Example 12 in that 3 parts by weight of polyamide fiber are added to the raw materials of the inner layer and the outer layer, and 4 parts by weight of sepiolite fiber are added to the raw materials of the middle layer.

[0042] Embodiment 15 An antistatic film for holding aqueous materials, which is different from Example 12 in that the diameter of the polyamide fiber is 300 nm and the length is 3 mm.

[0043] Example 16 An antistatic film for holding aqueous materials, which is different from Example 12 in that the diameter of the polyamide fiber is 500 nm and the length is 6 mm.

[0044] Embodiment 17 An antistatic film for holding aqueous materials, which is different from Example 12 in that the diameter of the sepiolite fiber is 5 μm and the length is 4 mm.

[0045] Embodiment 18 An antistatic film for holding aqueous materials, which is different from Example 12 in that the diameter of the sepiolite fiber is 10 μm and the length is 6 mm.

[0046] Embodiment 19 An antistatic film for holding aqueous materials, which is different from Example 12 in that polyamide fiber is not added to the raw materials of the inner layer and the outer layer.

[0047] Embodiment 20 An antistatic film for containing water-based materials, which is different from Example 12 in that no sepiolite fiber is added to the raw materials of the middle layer.

[0048] Embodiment 21 An antistatic film for holding water-based materials, which is different from Example 12 in that the polyamide fiber is modified before use, and the specific modification operation is as follows: The polyamide fiber raw material is dispersed in water to obtain a polyamide fiber aqueous dispersion with a mass fraction of 5%; then cetyltrimethylammonium bromide is added, and the weight ratio of cetyltrimethylammonium bromide to polyamide fiber is 1:5. After heating and stirring, the modified polyamide fiber is obtained after suction filtration, washing and drying.

[0049] Embodiment 22 An antistatic film for holding aqueous materials, which is different from Example 12 in that 2 parts by weight of a functional additive are also added to the raw materials of the middle layer, and the functional additive is composed of attapulgite powder and lanthanum oxide in a weight ratio of 8:1.

[0050] Embodiment 23 An antistatic film for holding aqueous materials, which is different from Example 22 in that the weight portion of the functional auxiliary agent added is 1 part.

[0051] Embodiment 24 An antistatic film for holding aqueous materials, which is different from Example 22 in that the weight parts of the functional additive added are 3 parts.

[0052] Embodiment 25 An antistatic film for holding aqueous materials, which is different from Example 22 in that the functional additive is composed of attapulgite powder and lanthanum oxide in a weight ratio of 6:1.

[0053] Embodiment 26 An antistatic film for holding aqueous materials, which is different from Example 22 in that the functional additive is composed of attapulgite powder and lanthanum oxide in a weight ratio of 10:1.

[0054] Embodiment 27 An antistatic film for holding aqueous materials, which is different from Example 22 in that attapulgite powder is not used in the functional additive.

[0055] Embodiment 28 An antistatic film for holding aqueous materials, which is different from Example 22 in that lanthanum oxide is not used in the functional additive.

[0056] Embodiment 29 An antistatic film for containing water-based materials, which is different from Example 22 in that no sepiolite fiber is used in the raw material of the middle layer.

[0057] Comparative Example Comparative Example 1 An antistatic film for holding aqueous materials, which is different from Example 1 in that the 8-carbon metallocene low-density polyethylene and other qualities in the raw materials required for preparing the inner layer, the middle layer and the outer layer are replaced by low-density polyethylene.

[0058] Performance test test samples: the antistatic films for holding aqueous materials obtained in Examples 1-29 were used as test samples 1-29, and the antistatic film for holding aqueous materials obtained in Comparative Example 1 was used as control sample 1.

[0059] Test method: Cut an antistatic film with an area of ​​5cm×5cm, fix its four sides, and place it horizontally for stress change test. The stress change test includes first applying a vertical pressure of 15Mpa to the center of the antistatic film to make it bend for 30 minutes; then remove the vertical pressure, apply a horizontal tension of 10Mpa along the transverse and longitudinal directions of the antistatic film, and continue for 30 minutes; then remove the horizontal tension, place the antistatic film in a high and low temperature alternating test box, the initial temperature is 25℃, first heat it up to 50℃ at 2℃ / min, then cool it down to -20℃ at 1.5℃ / min, and then heat it up to 25℃ at 1℃ / min; the above is recorded as a single stress change test cycle.

[0060] First, the antistatic film is tested using a film tear strength tester, and the obtained film tear strength value is recorded as A; then the antistatic film is subjected to the above-mentioned 3 stress change test cycles, and then tested using a film tear strength tester, and the obtained film tear strength value is recorded as B; finally, the tear strength loss rate of the antistatic film is calculated, and the tear strength loss rate = (AB) / A; and the greater the tear strength loss rate, the better the damage resistance of the antistatic film when it can withstand various stresses during transportation and daily use.

[0061] After completing the above tests on test samples 1-29 and control sample 1 in sequence, the corresponding results are recorded in Table 4.

[0062] Table 4 Test results of test samples 1-29 and control sample 1 From Examples 1-7 and Comparative Example 1 and Table 4, it can be seen that by using 8-carbon metallocene low-density polyethylene in combination with ordinary low-density polyethylene, and by using an inner layer, a middle layer and an outer layer structure composed of different raw materials, the antistatic film obtained can have a significantly lower tear strength loss rate after the above test, indicating that the antistatic film has excellent resistance to damage when subjected to various stresses during transportation and daily use.

[0063] It can be seen from Example 1 and Example 12-18 and Table 4 that by adding polyamide fiber to the raw materials of the inner and outer layers and adding sepiolite fiber to the raw materials of the middle layer, the damage resistance of the antistatic film can be further improved, and the tear strength loss rate obtained by the above test is significantly reduced; it can be seen from Example 19-20 and Table 4 that if only polyamide fiber or sepiolite fiber is used alone in the above application, although the tear strength loss rate can be reduced, the reduction is limited, and the sum of the corresponding effects brought by the separate application of the two is far less than the excellent compounding of the two. It can be seen that at the interface between the middle layer and the inner and outer layers, sepiolite fiber and polyamide fiber form a certain coordination, which brings about a significant improvement in the damage resistance of the antistatic film. It can be seen from Example 21 and Table 4 that the polyamide fiber is modified before use, which can improve the coordination effect with sepiolite fiber, thereby bringing about a further improvement in the damage resistance of the antistatic film, and the tear strength loss rate obtained by the above test is also further reduced.

[0064] Combining Example 12 and Example 22-26 with Table 4, it can be seen that by using a functional additive composed of attapulgite powder and lanthanum oxide in the middle layer, the tear strength loss rate can be further reduced; Combining Example 27-28 with Table 4, it can be seen that if only attapulgite powder or lanthanum oxide is added and used alone, although the tear strength loss rate can be reduced, the sum of the corresponding effects brought by the use of attapulgite powder and lanthanum oxide alone is far less than the excellent compounding of the two. It can be seen that the combination of attapulgite powder and lanthanum oxide can bring a significant improvement effect of 1+1>2, so that the antistatic film can be significantly improved in terms of its resistance to damage when subjected to various stresses during transportation and daily use. Combining Example 29 with Table 4, it can be seen that if there is no sepiolite fiber in the middle layer, the corresponding effect brought by the functional additive will be significantly reduced, indicating that the functional additive can rely on sepiolite fiber to bring better effects, and thus an antistatic film with relatively excellent quality can be obtained.

[0065] This specific embodiment is merely an explanation of the present application and is not a limitation of the present application. After reading this specification, those skilled in the art may make modifications to the present embodiment without any creative contribution as needed, but such modifications are protected by the patent law as long as they are within the scope of the claims of the present application.

Claims

1. An antistatic film for holding water-based materials, characterized in that: It includes an inner layer, a middle layer and an outer layer structure obtained by three-layer co-extrusion; The inner layer is made of the following raw materials in parts by weight: 40-50 parts of low density polyethylene; 40-50 parts of 8-carbon metallocene low-density polyethylene; 2-3 copies of antistatic masterbatch; The middle layer is made of the following raw materials in parts by weight: 55-65 parts of low density polyethylene; 8-carbon metallocene low-density polyethylene 35-45 parts; 2-3 copies of antistatic masterbatch; The outer layer is made of the following raw materials in parts by weight: 30-40 parts of low density polyethylene; 8-carbon metallocene low-density polyethylene 55-65 parts; 2-3 copies of antistatic masterbatch.

2. The antistatic film for holding aqueous materials according to claim 1, characterized in that: The thickness of the inner layer is 20-30 μm; the thickness of the middle layer is 140-160 μm; and the thickness of the outer layer is 20-30 μm.

3. The antistatic film for holding aqueous materials according to claim 1, characterized in that: 3-5 parts by weight of polyamide fiber are added to the raw materials of the inner layer and the outer layer, and 4-6 parts by weight of sepiolite fiber are added to the raw materials of the middle layer.

4. The antistatic film for holding aqueous materials according to claim 3, characterized in that: The polyamide fiber has a diameter of 300-500 nm and a length of 3-6 mm.

5. The antistatic film for holding aqueous materials according to claim 3, characterized in that: The sepiolite fiber has a diameter of 5-10 μm and a length of 4-6 mm.

6. The antistatic film for holding aqueous materials according to claim 3, characterized in that: The polyamide fiber is subjected to modification treatment before use, and the specific modification treatment operation is as follows: The polyamide fiber raw material is dispersed in water, hexadecyltrimethylammonium bromide is added, the mixture is heated and stirred, and then filtered, washed and dried to obtain the modified polyamide fiber.

7. The antistatic film for holding aqueous materials according to claim 3, characterized in that: The raw materials of the middle layer are further added with 1-3 parts by weight of a functional additive, wherein the functional additive is composed of attapulgite powder and lanthanum oxide, and the weight ratio of the attapulgite powder to lanthanum oxide is (6-10):

1.

8. The antistatic film for holding aqueous materials according to claim 7, characterized in that: The weight ratio of the attapulgite powder to lanthanum oxide is 8:

1.

9. The method for preparing the antistatic film for holding aqueous materials according to claim 1, characterized in that: The following steps are involved: (1) Prepare the raw materials required for the preparation of the inner layer, the middle layer and the outer layer according to the proportions; (2) The raw materials required for preparing the inner layer, the middle layer and the outer layer are mixed respectively, melt-kneaded respectively, and then a sheet is obtained by three-layer co-extrusion using an extruder; (3) Preheating the sheet obtained in step (2) and then stretching and shaping it to obtain an antistatic film for containing water-based materials.

10. The method for preparing an antistatic film for holding aqueous materials according to claim 9, characterized in that: In step (2), the melting and kneading temperature of the inner layer, the middle layer and the outer layer is 150-160°C, and the extrusion temperature in the extruder is 170-200°C.

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