A stain-resistant antistatic PE protective film and a preparation method thereof

Abstract

The application relates to a stain-resistant and antistatic PE protective film and a preparation method thereof, and belongs to the technical field of high polymer materials. The polyethylene protective film comprises three layers of an outer layer, a middle layer and an inner layer in sequence, and modified chlorinated polyethylene is added to the inner layer and the outer layer. The modified chlorinated polyethylene not only effectively solves the migration problem of the antibacterial agent in the high polymer material, but also enhances the binding capacity with the polar groups (hydroxyl groups and ether bonds) in the antistatic agent by using ion-dipole interaction, accelerates the migration speed of the antistatic agent from the middle layer to the interface region of the outer / inner layer of the material, improves the initial antistatic effect of the material, and further concentrates the antistatic agent in the middle layer, uses the quaternary ammonium salt structure of the outer / inner layer to anchor the antistatic agent, limits the migration region of the antistatic agent, and effectively reduces the risk of antistatic agent exuding and polluting the surface of a sensitive substrate.

Description

Technical Field

[0001] This invention belongs to the field of polymer materials technology, specifically, it relates to a stain-resistant and antistatic PE protective film and its preparation method. Background Technology

[0002] Polyethylene protective films have good transparency, making them an ideal material for preparing optical protective films. However, polyethylene materials have a high intrinsic resistivity, typically around 10. 16 ~10 17 Ω, static electricity easily accumulates during transportation and friction. The static electricity buildup on the surface of polyethylene protective film not only easily attracts dust and pollutants, but may also cause electrostatic discharge damage to equipment. Adding antistatic agents can reduce the surface resistance of polyethylene protective film and thus reduce static electricity buildup. However, the amount of permanent antistatic agent added is relatively large, which will affect the light transmittance of polyethylene protective film. Moreover, permanent antistatic agents take effect slowly and are not suitable for products such as protective films that need to take effect quickly and have a short service life. Although small molecule antistatic agents have better antistatic effects and require less addition, they are easy to migrate to the outside during use, which will not only cause the antistatic performance to fail, but may also affect the appearance of the protective film and even the surface of sensitive substrates. To solve the above technical defects, this invention provides a stain-resistant and antistatic PE protective film and its preparation method. Summary of the Invention

[0003] The purpose of this invention is to provide a stain-resistant and antistatic PE protective film and its preparation method, so as to solve the problems mentioned in the background art.

[0004] The objective of this invention can be achieved through the following technical solutions:

[0005] A method for preparing a stain-resistant and antistatic PE protective film includes the following steps:

[0006] S1. A modified chlorinated polyethylene is obtained by grafting a guanidine antibacterial agent onto the surface of chlorinated polyethylene.

[0007] S2. Low-density polyethylene, metallocene low-density polyethylene, modified chlorinated polyethylene, and antioxidant are mixed together as the outer layer material; low-density polyethylene, metallocene low-density polyethylene, modified chlorinated polyethylene, and antioxidant are mixed together as the inner layer material; and low-density polyethylene, metallocene medium-density polyethylene, and antistatic agent are mixed together as the middle layer material.

[0008] S3. The outer layer material, middle layer material and inner layer material are co-extruded in multiple layers to obtain a stain-resistant and antistatic PE protective film.

[0009] Furthermore, the guanidine antibacterial agent is at least one of 1,1-dimethylguanidine, 1,1-diethylguanidine, and 1,1-diisopropylguanidine.

[0010] Furthermore, the chlorine content of the chlorinated polyethylene is 25-35%.

[0011] Furthermore, the antistatic agent is a nonionic antistatic agent.

[0012] Furthermore, the antioxidant is at least one of antioxidant 1010, antioxidant 1035, antioxidant 1076, and antioxidant 168.

[0013] Furthermore, the mass ratio of guanidine antibacterial agent to chlorinated polyethylene is 6.2–14.4:10, based on mass parts.

[0014] Furthermore, by mass fraction, the mass ratio of low-density polyethylene, metallocene low-density polyethylene, modified chlorinated polyethylene, and antioxidant in the outer layer material is 60–70: 27–36: 3–4: 0.1–0.5.

[0015] Furthermore, by mass fraction, the ratio of low-density polyethylene, metallocene medium-density polyethylene, modified chlorinated polyethylene, and antioxidant in the inner layer material is 60–70: 27–36: 3–4: 0.1–0.5.

[0016] Furthermore, by mass fraction, the mass ratio of low-density polyethylene, metallocene low-density polyethylene, and antistatic agent in the middle layer material is 45–55: 45–55: 0.8–1.6.

[0017] A stain-resistant and antistatic PE protective film is prepared by any of the above preparation steps.

[0018] The beneficial effects of this invention are:

[0019] 1) This invention grafts guanidine antibacterial agents onto the surface of chlorinated polyethylene, effectively solving the problem of antibacterial agent migration in polymer materials. Moreover, the quaternary ammonium salt structure formed after grafting can enhance the antibacterial effect of guanidine antibacterial agents by utilizing its own strong electrostatic attraction.

[0020] 2) The polyethylene protective film of the present invention comprises three layers in sequence: outer, middle and inner. Positively charged quaternary ammonium salt structures are grafted onto the inner and outer layers, which can enhance the binding ability with polar groups (hydroxyl groups, ether bonds) in the antistatic agent by utilizing ion-dipole interactions, accelerate the migration speed of the antistatic agent from the middle layer to the interface region of the outer / inner layer of the material, and improve the initial antistatic effect of the material. In addition, by concentrating the antistatic agent in the middle layer, the quaternary ammonium salt structure of the outer / inner layer can anchor the antistatic agent, limit the migration area of ​​the antistatic agent, and effectively reduce the risk of antistatic agent seepage and contamination of the surface of sensitive substrate.

[0021] 3) The outer / inner layers of the polyethylene protective film of the present invention are modified chlorinated polyethylene with a quaternary ammonium salt structure, which can significantly enhance the polarity of the outer / inner layers of the material, enhance the bonding strength between the polyethylene protective film and the protected interface, and improve the adhesion of the polyethylene protective film. Detailed Implementation

[0022] The technical solutions of the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments in this application specification, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection claimed in this application.

[0023] The raw materials used in this invention are not particularly restricted in terms of their source; they can be purchased from the market or prepared using conventional methods known to those skilled in the art.

[0024] Example 1

[0025] A method for preparing a stain-resistant and antistatic PE protective film includes the following steps:

[0026] S1. Dissolve 10 parts by mass of chlorinated polyethylene with a chlorine content of 25% in 100 parts by mass of dichloroethane, add 6.2 parts by mass of 1,1-dimethylguanidine to the system, then raise the system temperature to 60°C and react at 60°C for 16 hours. After the reaction is completed, remove the solvent by rotary evaporation, wash the remaining solid with deionized water and dry to obtain modified chlorinated polyethylene.

[0027] S2. A mixture of 70 parts by mass of low-density polyethylene, 27 parts by mass of metallocene low-density polyethylene, 3 parts by mass of modified chlorinated polyethylene, and 0.1 parts by mass of antioxidant 1010 is used as the outer layer material; a mixture of 70 parts by mass of low-density polyethylene, 27 parts by mass of metallocene low-density polyethylene, 3 parts by mass of modified chlorinated polyethylene, and 0.1 parts by mass of antioxidant 1010 is used as the inner layer material; and a mixture of 55 parts by mass of low-density polyethylene, 45 parts by mass of metallocene medium-density polyethylene, and 0.8 parts by mass of ethoxylated laurylamine is used as the middle layer material.

[0028] S3. A stain-resistant and antistatic PE protective film is obtained by multi-layer co-extrusion of outer layer material, middle layer material and inner layer material. The melt extrusion temperature of the outer layer material is 175℃, the melt extrusion temperature of the middle layer material is 185℃ and the melt extrusion temperature of the inner layer material is 175℃.

[0029] A stain-resistant and antistatic PE protective film is prepared by the above preparation steps.

[0030] Example 2

[0031] A method for preparing a stain-resistant and antistatic PE protective film includes the following steps:

[0032] S1. Dissolve 10 parts by mass of chlorinated polyethylene with a chlorine content of 30% in 100 parts by mass of dichloroethane, add 9.8 parts by mass of 1,1-diethylguanidine to the system, then raise the system temperature to 70°C and react at 70°C for 20 hours. After the reaction is completed, remove the solvent by rotary evaporation, and wash the remaining solid with deionized water and dry to obtain modified chlorinated polyethylene.

[0033] S2. A mixture of 65 parts by weight of low-density polyethylene, 31.5 parts by weight of metallocene low-density polyethylene, 3.5 parts by weight of modified chlorinated polyethylene, 0.2 parts by weight of antioxidant 1035, and 0.1 parts by weight of antioxidant 168 is used as the outer layer material; a mixture of 65 parts by weight of low-density polyethylene, 31.5 parts by weight of metallocene low-density polyethylene, 3.5 parts by weight of modified chlorinated polyethylene, 0.2 parts by weight of antioxidant 1035, and 0.1 parts by weight of antioxidant 168 is used as the inner layer material; and a mixture of 50 parts by weight of low-density polyethylene, 50 parts by weight of metallocene medium-density polyethylene, and 1.2 parts by weight of ethoxylated stearamine is used as the middle layer material.

[0034] S3. A stain-resistant and antistatic PE protective film is obtained by multi-layer co-extrusion of outer layer material, middle layer material and inner layer material. The melt extrusion temperature of the outer layer material is 180℃, the melt extrusion temperature of the middle layer material is 190℃ and the melt extrusion temperature of the inner layer material is 180℃.

[0035] A stain-resistant and antistatic PE protective film is prepared by the above preparation steps.

[0036] Example 3

[0037] A method for preparing a stain-resistant and antistatic PE protective film includes the following steps:

[0038] S1. Dissolve 10 parts by mass of chlorinated polyethylene with a chlorine content of 35% in 100 parts by mass of dichloroethane, add 14.4 parts by mass of 1,1-diisopropylguanidine to the system, then raise the system temperature to 80℃ and react at 80℃ for 24h. After the reaction is completed, remove the solvent by rotary evaporation, wash the remaining solid with deionized water and dry to obtain modified chlorinated polyethylene.

[0039] S2. A mixture of 60 parts by weight of low-density polyethylene, 36 parts by weight of metallocene low-density polyethylene, 4 parts by weight of modified chlorinated polyethylene, 0.4 parts by weight of antioxidant 1076, and 0.1 parts by weight of antioxidant 168 is used as the outer layer material; a mixture of 60 parts by weight of low-density polyethylene, 36 parts by weight of metallocene low-density polyethylene, 4 parts by weight of modified chlorinated polyethylene, 0.4 parts by weight of antioxidant 1076, and 0.1 parts by weight of antioxidant 168 is used as the inner layer material; and a mixture of 45 parts by weight of low-density polyethylene, 55 parts by weight of metallocene medium-density polyethylene, and 1.6 parts by weight of ethoxylated stearamine is used as the middle layer material.

[0040] S3. A stain-resistant and antistatic PE protective film is obtained by multi-layer co-extrusion of outer layer material, middle layer material and inner layer material. The melt extrusion temperature of the outer layer material is 185℃, the melt extrusion temperature of the middle layer material is 195℃ and the melt extrusion temperature of the inner layer material is 185℃.

[0041] A stain-resistant and antistatic PE protective film is prepared by the above preparation steps.

[0042] Comparative Example 1

[0043] The difference between this comparative example and Example 1 is that the chlorinated polyethylene is not modified, but is directly used to prepare the inner / outer layer material, and the antibacterial agent is directly added to the inner / outer layer material in proportion.

[0044] A method for preparing a stain-resistant and antistatic PE protective film includes the following steps:

[0045] S1. A mixture of 70 parts by weight of low-density polyethylene, 27 parts by weight of metallocene low-density polyethylene, 1.85 parts by weight of chlorinated polyethylene, 1.15 parts by weight of 1,1-dimethylguanidine, and 0.1 parts by weight of antioxidant 1010 is used as the outer layer material; a mixture of 70 parts by weight of low-density polyethylene, 27 parts by weight of metallocene low-density polyethylene, 1.85 parts by weight of chlorinated polyethylene, 1.15 parts by weight of 1,1-dimethylguanidine, and 0.1 parts by weight of antioxidant 1010 is used as the inner layer material; and a mixture of 55 parts by weight of low-density polyethylene, 45 parts by weight of metallocene medium-density polyethylene, and 0.8 parts by weight of ethoxylated laurylamine is used as the middle layer material.

[0046] S2. A stain-resistant and antistatic PE protective film is obtained by multi-layer co-extrusion of outer layer material, middle layer material and inner layer material. The melt extrusion temperature of the outer layer material is 175℃, the melt extrusion temperature of the middle layer material is 185℃ and the melt extrusion temperature of the inner layer material is 175℃.

[0047] A stain-resistant and antistatic PE protective film is prepared by the above preparation steps.

[0048] Experimental Example 1

[0049] The performance of the stain-resistant and antistatic PE protective films in Examples 1-3 and Comparative Example 1 was tested. The peel strength, surface resistance, and antibacterial rate of each component of the polyethylene protective film were tested respectively. The surface resistance and antibacterial rate were tested again after 5000 rubs. The test results are shown in Table 1.

[0050] Peel strength: The peel strength of each component of the polyethylene protective film was tested in accordance with the national standard GB / T 25256-2010 "Test method for 180° peel force and residual adhesion of optical functional film release film".

[0051] Surface resistance: The surface resistance of each component of the polyethylene protective film was tested using a surface resistivity tester.

[0052] Antibacterial rate: The antibacterial rate against Escherichia coli and Staphylococcus aureus was tested according to the national standard GB / T 31402-2015 "Test Method for Antibacterial Properties of Plastic Surfaces".

[0053] Table 1

[0054]

[0055] As can be seen from Table 1, the polyethylene protective film of the present invention in Examples 1 to 3 has higher peel strength, stronger initial antibacterial rate and surface resistance, and lower loss after friction, and can be widely used in the field of medical device protection.

[0056] The descriptions of the above embodiments are merely illustrative of the methods and core ideas of the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a stain-resistant and antistatic PE protective film, characterized in that, Includes the following steps: S1. A modified chlorinated polyethylene is obtained by grafting a guanidine antibacterial agent onto the surface of chlorinated polyethylene. S2. Low-density polyethylene, metallocene low-density polyethylene, modified chlorinated polyethylene, and antioxidant are mixed together as the outer layer material; low-density polyethylene, metallocene low-density polyethylene, modified chlorinated polyethylene, and antioxidant are mixed together as the inner layer material; and low-density polyethylene, metallocene medium-density polyethylene, and antistatic agent are mixed together as the middle layer material. S3. A stain-resistant and antistatic PE protective film is obtained by co-extruding the outer layer material, middle layer material and inner layer material in multiple layers. In step S1, 10 parts by mass of chlorinated polyethylene with a chlorine content of 25% are dissolved in 100 parts by mass of dichloroethane, and 6.2 parts by mass of 1,1-dimethylguanidine are added to the system. Then the system temperature is raised to 60°C and reacted at 60°C for 16 hours. After the reaction is completed, the solvent is removed by rotary evaporation, and the remaining solid is washed with deionized water and dried to obtain modified chlorinated polyethylene. The guanidine antibacterial agent is at least one of 1,1-dimethylguanidine, 1,1-diethylguanidine, and 1,1-diisopropylguanidine. Specifically, by mass percentage, the outer layer material contains low-density polyethylene, metallocene low-density polyethylene, modified chlorinated polyethylene, and antioxidant in a ratio of 60–70:27–36:3–4:0.1–0.5; the inner layer material contains low-density polyethylene, metallocene low-density polyethylene, modified chlorinated polyethylene, and antioxidant in a ratio of 60–70:27–36:3–4:0.1–0.5; and the middle layer material contains low-density polyethylene, metallocene medium-density polyethylene, and antistatic agent in a ratio of 45–55:45–55:0.8–1.

6.

2. The method for preparing a stain-resistant and antistatic PE protective film according to claim 1, characterized in that, The chlorine content of the chlorinated polyethylene is 25-35%.

3. The method for preparing a stain-resistant and antistatic PE protective film according to claim 1, characterized in that, The antistatic agent is a nonionic antistatic agent.

4. The method for preparing a stain-resistant and antistatic PE protective film according to claim 1, characterized in that, The antioxidant is at least one of antioxidant 1010, antioxidant 1035, antioxidant 1076, and antioxidant 168.

5. The method for preparing a stain-resistant and antistatic PE protective film according to claim 1, characterized in that, The mass ratio of guanidine antibacterial agent to chlorinated polyethylene is 6.2–14.4:

10.

6. A stain-resistant and antistatic PE protective film, characterized in that, A stain-resistant and antistatic PE protective film is prepared by the preparation method described in any one of claims 1 to 5.

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