Heat-resistant biaxially oriented polypropylene film and preparation method thereof

Abstract

The invention relates to the technical field of polypropylene films, and proposes a heat-resistant biaxially oriented polypropylene film and a preparation method thereof. A heat-resistant biaxially oriented polypropylene film comprises a base layer and a surface layer arranged on the base layer, wherein the raw materials of the base layer comprise the following components in parts by weight: 100 parts of polypropylene resin, 10-20 parts of filler, 0.5-1 part of antioxidant, 1-2 parts of antistatic agent, 2-4 parts of lubricant, and the filler is a modifier-modified mica powder, wherein the modifier of the modifier-modified mica powder comprises a compound containing a carboxyl group and a benzene ring and / or palm wax. Through the above technical scheme, the problem of poor heat resistance of the biaxially oriented polypropylene film in the related art is solved.

Description

Technical Field

[0001] The invention relates to the technical field of polypropylene films, and in particular to a heat-resistant biaxially oriented polypropylene film and a preparation method thereof. Background Art

[0002] Biaxially oriented polypropylene film (BOPP) is a film made of polypropylene resin as the main raw material, through longitudinal and transverse biaxial stretching and other processes. There are two process methods: stentering method and blow molding method. The former is to heat the raw material and extrude it into a thick film and then stretch it in the longitudinal and transverse directions; the latter is to extrude the molten extruded raw material into a thick-walled prototype tube, and then blow it with compressed air for transverse stretching and longitudinal stretching through a lifting and curling device. Biaxially oriented polypropylene film has the characteristics of light weight, moisture resistance, non-toxic and odorless, good mechanical properties, and good printing properties. It is widely used as packaging for food, medicine, daily light industry and other products. It can also be compounded with cellophane, aluminum foil and other composite packaging materials. Although biaxially oriented polypropylene film has many excellent properties and a wide range of applications, its disadvantage of easy shrinkage when heated limits its more applications. Therefore, how to improve the heat resistance of biaxially oriented polypropylene film is a technical problem that needs to be solved urgently in this field. Summary of the invention

[0003] The invention provides a heat-resistant biaxially oriented polypropylene film and a preparation method thereof, which solves the problem of poor heat resistance of the biaxially oriented polypropylene film in the related art.

[0004] The technical solution of the present invention is as follows:

[0005] The invention provides a heat-resistant biaxially oriented polypropylene film, comprising a base layer and a surface layer arranged on the base layer, wherein the raw materials of the base layer comprise the following components in parts by weight: 100 parts of polypropylene resin, 10-20 parts of filler, 0.5-1 part of antioxidant, 1-2 parts of antistatic agent, and 2-4 parts of lubricant, wherein the filler is modifier-modified mica powder, and the modifier of the modifier-modified mica powder comprises a compound containing a carboxyl group and a benzene ring and / or palm wax.

[0006] As a further technical solution, the modifier of the modifier-modified mica powder includes a compound containing a carboxyl group and a benzene ring and palm wax in a mass ratio of 1:9 to 9:1.

[0007] In the present invention, the modifier for modifying mica powder includes a compound containing a carboxyl group and a benzene ring and palm wax in a mass ratio of 1:9 to 9:1, thereby further improving the heat resistance of the biaxially oriented polypropylene film.

[0008] As a further technical solution, the mass ratio of the compound containing a carboxyl group and a benzene ring to the palm wax is 4:6~6:4.

[0009] In the present invention, the mass ratio of the compound containing a carboxyl group and a benzene ring to the palm wax is limited to 4:6-6:4, thereby further improving the heat resistance of the biaxially oriented polypropylene film.

[0010] As a further technical solution, the compound containing a carboxyl group and a benzene ring is 3-phenyl-cyclobutanecarboxylic acid.

[0011] As a further technical solution, the raw materials of the modifier-modified mica powder include the modifier and the mica powder in a mass ratio of 1 to 6:40.

[0012] As a further technical solution, the mass ratio of the modifier to the mica powder is 2.5~4:40.

[0013] In the present invention, the mass ratio of the modifier to the mica powder is limited to 2.5-4:40, thereby further improving the heat resistance of the biaxially oriented polypropylene film.

[0014] As a further technical solution, when the modifier of the mica powder modified by the modifier comprises a compound containing a carboxyl group and a benzene ring and palm wax, the preparation method of the mica powder modified by the modifier comprises the following steps:

[0015] S1. Dissolving a compound containing a carboxyl group and a benzene ring in a solvent, adding mica powder, mixing evenly, and drying to obtain pre-modified mica powder;

[0016] S2. After dissolving palm wax in a solvent, add pre-modified mica powder, mix evenly, and dry to obtain modifier-modified mica powder.

[0017] The present invention further improves the heat resistance of the biaxially stretched polypropylene film by limiting the preparation method of the modifier-modified mica powder when the modifier of the modifier-modified mica powder includes a compound containing a carboxyl group and a benzene ring and palm wax.

[0018] As a further technical solution, the raw material of the surface layer includes the following components in parts by weight: 100 parts of polypropylene resin and 1 to 3 parts of anti-sticking agent.

[0019] As a further technical solution, the antistatic agent includes one or more of antistatic agent KJ-200, antistatic agent HKD-300, and antistatic agent MGS-20.

[0020] As a further technical solution, the antioxidant includes one or more of antioxidant 1010, antioxidant 1076, and antioxidant 245.

[0021] As a further technical solution, the lubricant includes one or both of oleamide and erucamide.

[0022] As a further technical solution, the anti-sticking agent includes one or more of silicon dioxide, polymethyl methacrylate, and polymethylsiloxane.

[0023] The present invention also provides a method for preparing a heat-resistant biaxially oriented polypropylene film, comprising the following steps:

[0024] The raw materials of the base layer and the raw materials of the surface layer are respectively mixed evenly, and then co-extruded, cast, biaxially stretched, corona treated, and rolled to obtain a heat-resistant biaxially stretched polypropylene film.

[0025] The working principle and beneficial effects of the present invention are:

[0026] In the present invention, mica powder modified by a modifier is selected as the filler of the heat-resistant biaxially stretched polypropylene film base layer, the modifier is a compound containing carboxyl groups and benzene rings and / or palm wax, the mica powder has heat resistance, the compound containing carboxyl groups and benzene rings is combined with the mica powder so that the surface of the modified mica powder has benzene rings, the high temperature resistance of the modified mica powder is enhanced, and the affinity of the mica powder with the polypropylene resin is improved; the mica powder is modified by the palm wax, and on the basis of improving the affinity of the mica powder with the polypropylene resin, the dispersibility of the mica powder is also improved, and the dispersibility between the raw materials of the biaxially stretched polypropylene film base layer is also improved, therefore, the mica powder modified by the compound containing carboxyl groups and benzene rings and / or palm wax is used to improve the heat resistance of the biaxially stretched polypropylene film. DETAILED DESCRIPTION

[0027] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] In the following examples and comparative examples, the parameters of the raw materials are as follows:

[0029] The particle size of mica powder is 1250 mesh;

[0030] The product number of polypropylene resin is M250E, which was purchased from Shanghai Younoshi Plastic Technology Co., Ltd.;

[0031] Polymethyl methacrylate was IH830 of LX of Korea; purchased from Dongguan Taotao Plastic Raw Materials Co., Ltd.;

[0032] The model of palm wax is T1, purchased from Guangzhou Fufei Chemical Technology Co., Ltd.;

[0033] The particle size of silica was 2000 mesh.

[0034] Example 1

[0035] A heat-resistant biaxially oriented polypropylene film comprises a base layer with a thickness of 13 μm and a surface layer with a thickness of 2 μm arranged on the base layer. The preparation method thereof comprises the following steps:

[0036] S1, dissolving 1 part of 3-phenyl-cyclobutanecarboxylic acid in 50 parts of chloroform, adding 40 parts of mica powder, mixing evenly, and drying to obtain modifier-modified mica powder;

[0037] S2. The base layer raw materials: 100 parts of polypropylene resin, 10 parts of modifier modified mica powder, 0.5 parts of antioxidant 1010, 1 part of antistatic agent KJ-200, 2 parts of oleic acid amide, and the surface layer raw materials: 100 parts of polypropylene resin and 1 part of polymethyl methacrylate are mixed evenly, co-extruded, cast into sheets, longitudinally stretched 4.5 times at 130°C, shaped, transversely stretched 9.5 times at 155°C, shaped, corona treated, and rolled to obtain a heat-resistant biaxially oriented polypropylene film.

[0038] Example 2

[0039] A heat-resistant biaxially oriented polypropylene film comprises a base layer with a thickness of 13 μm and a surface layer with a thickness of 2 μm arranged on the base layer. The preparation method thereof comprises the following steps:

[0040] S1, dissolving 6 parts of palm wax in 50 parts of chloroform, adding 40 parts of mica powder, mixing evenly, and drying to obtain modifier-modified mica powder;

[0041] S2. The base layer raw materials: 100 parts of polypropylene resin, 20 parts of modified mica powder, 1 part of antioxidant 1076, 2 parts of antistatic agent HKD-300, 4 parts of erucamide, and the surface layer raw materials: 100 parts of polypropylene resin and 3 parts of silicon dioxide are mixed evenly, co-extruded, cast into sheets, longitudinally stretched 4.5 times at 130°C, shaped, transversely stretched 9.5 times at 155°C, shaped, corona treated, and rolled to obtain a heat-resistant biaxially oriented polypropylene film.

[0042] Example 3

[0043] The only difference from Example 1 is that 3-phenyl-cyclobutanecarboxylic acid is replaced by an equal amount of palm wax.

[0044] Example 4

[0045] The only difference from Example 1 is that 1 part of 3-phenyl-cyclobutanecarboxylic acid is replaced by 0.1 part of 3-phenyl-cyclobutanecarboxylic acid and 0.9 part of palm wax.

[0046] Example 5

[0047] The only difference from Example 4 is: 0.9 part of 3-phenyl-cyclobutanecarboxylic acid and 0.1 part of palm wax.

[0048] Example 6

[0049] The only difference from Example 4 is: 0.4 part of 3-phenyl-cyclobutanecarboxylic acid and 0.6 part of palm wax.

[0050] Example 7

[0051] The only difference from Example 4 is: 0.6 part of 3-phenyl-cyclobutanecarboxylic acid and 0.4 part of palm wax.

[0052] Example 8

[0053] The only difference from Example 7 is: 3.6 parts of 3-phenyl-cyclobutanecarboxylic acid and 2.4 parts of palm wax.

[0054] Example 9

[0055] The only difference from Example 7 is: 1.5 parts of 3-phenyl-cyclobutanecarboxylic acid and 1 part of palm wax.

[0056] Example 10

[0057] The only difference from Example 7 is: 2.4 parts of 3-phenyl-cyclobutanecarboxylic acid and 1.6 parts of palm wax.

[0058] Embodiment 11

[0059] A heat-resistant biaxially oriented polypropylene film comprises a base layer with a thickness of 13 μm and a surface layer with a thickness of 2 μm arranged on the base layer. The preparation method thereof comprises the following steps:

[0060] S1, dissolving 2.4 parts of 3-phenyl-cyclobutanecarboxylic acid in 50 parts of chloroform, adding 40 parts of mica powder, mixing evenly, and drying to obtain pre-modified mica powder;

[0061] After dissolving 1.6 parts of palm wax in 50 parts of chloroform, add pre-modified mica powder, mix well, and dry to obtain modifier-modified mica powder;

[0062] S2. The base layer raw materials: 100 parts of polypropylene resin, 10 parts of modifier modified mica powder, 0.5 parts of antioxidant 1010, 1 part of antistatic agent KJ-200, 2 parts of oleic acid amide, and the surface layer raw materials: 100 parts of polypropylene resin and 1 part of polymethyl methacrylate are mixed evenly, co-extruded, cast into sheets, longitudinally stretched 4.5 times at 130°C, shaped, transversely stretched 9.5 times at 155°C, shaped, corona treated, and rolled to obtain a heat-resistant biaxially oriented polypropylene film.

[0063] Example 12

[0064] A heat-resistant biaxially oriented polypropylene film comprises a base layer with a thickness of 13 μm and a surface layer with a thickness of 2 μm arranged on the base layer. The preparation method thereof comprises the following steps:

[0065] S1, dissolving 1.6 parts of palm wax in 50 parts of chloroform, adding 40 parts of mica powder, mixing evenly, and drying to obtain pre-modified mica powder;

[0066] After dissolving 2.4 parts of 3-phenyl-cyclobutanecarboxylic acid in 50 parts of chloroform, adding pre-modified mica powder, mixing evenly, and drying to obtain modifier-modified mica powder;

[0067] S2. The base layer raw materials: 100 parts of polypropylene resin, 10 parts of modifier modified mica powder, 0.5 parts of antioxidant 1010, 1 part of antistatic agent KJ-200, 2 parts of oleic acid amide, and the surface layer raw materials: 100 parts of polypropylene resin and 1 part of polymethyl methacrylate are mixed evenly, co-extruded, cast into sheets, longitudinally stretched 4.5 times at 130°C, shaped, transversely stretched 9.5 times at 155°C, shaped, corona treated, and rolled to obtain a heat-resistant biaxially oriented polypropylene film.

[0068] Comparative Example 1

[0069] A heat-resistant biaxially oriented polypropylene film comprises a base layer with a thickness of 13 μm and a surface layer with a thickness of 2 μm arranged on the base layer. The preparation method thereof comprises the following steps:

[0070] The base layer raw materials: 100 parts of polypropylene resin, 10 parts of mica powder, 0.5 parts of antioxidant 1010, 1 part of antistatic agent KJ-200, 2 parts of oleic acid amide, and the surface layer raw materials: 100 parts of polypropylene resin and 1 part of polymethyl methacrylate were mixed uniformly, co-extruded, cast into sheets, longitudinally stretched 4.5 times at 130°C, shaped, transversely stretched 9.5 times at 155°C, shaped, corona treated, and rolled to obtain a heat-resistant biaxially oriented polypropylene film.

[0071] Test example

[0072] The heat-resistant biaxially oriented polypropylene films prepared in Examples 1 to 12 and Comparative Example 1 were tested for heat shrinkage and transverse tensile strength according to the standard of GB / T 10003-2008. The results are shown in Table 1.

[0073] Table 1 Test results of thermal shrinkage and transverse tensile strength of Examples 1 to 12 and Comparative Example 1

[0074]

[0075] Compared with Comparative Example 1, the filler in the heat-resistant biaxially oriented polypropylene film prepared in Example 1 and Examples 3 to 10 is mica powder modified by a modifier. As a result, the transverse and longitudinal heat shrinkage rates of Example 1 and Examples 3 to 10 are smaller than those of Comparative Example 1, and the transverse tensile strength is greater than that of Comparative Example 1, indicating that the heat resistance and mechanical strength of the heat-resistant biaxially oriented polypropylene film can be improved by using a compound containing a carboxyl group and a benzene ring and / or palm wax-modified mica powder.

[0076] The transverse and longitudinal heat shrinkage rates of the heat-resistant biaxially oriented polypropylene films prepared in Examples 4 to 7 are smaller than those in Example 1 and Example 3, and the transverse tensile strength is greater than that in Example 1 and Example 3, indicating that the modifier of the mica powder modified by the modifier is a compound containing a carboxyl group and a benzene ring and palm wax, which further improves the heat resistance and mechanical strength of the biaxially oriented polypropylene film.

[0077] The transverse and longitudinal heat shrinkage rates of the heat-resistant biaxially oriented polypropylene films prepared in Examples 6-7 are smaller than those in Examples 4-5, and the transverse tensile strength is greater than that in Examples 4-5, indicating that the mass ratio of the compound containing carboxyl groups and benzene rings to palm wax is 4:6-6:4, which further improves the heat resistance and mechanical strength of the biaxially oriented polypropylene films.

[0078] The transverse and longitudinal heat shrinkage rates of the heat-resistant biaxially oriented polypropylene films prepared in Examples 9 to 10 are smaller than those in Examples 7 to 8, and the transverse tensile strength is greater than that in Examples 7 to 8, indicating that the mass ratio of the modifier to the mica powder is 2.5 to 4:40, which further improves the heat resistance and mechanical strength of the biaxially oriented polypropylene films.

[0079] The transverse and longitudinal heat shrinkage rates of the heat-resistant biaxially oriented polypropylene film prepared in Example 11 are smaller than those in Example 10 and Example 12, and the transverse tensile strength is greater than those in Example 10 and Example 12, indicating that the mica powder is first modified with a compound containing carboxyl groups and benzene rings and then modified with palm wax, which further improves the heat resistance and mechanical strength of the biaxially oriented polypropylene film.

[0080] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A heat-resistant biaxially oriented polypropylene film, comprising a base layer and a surface layer arranged on the base layer, characterized in that: The raw materials of the base layer include the following components in parts by weight: 100 parts of polypropylene resin, 10-20 parts of filler, 0.5-1 parts of antioxidant, 1-2 parts of antistatic agent, 2-4 parts of lubricant, the filler is modifier-modified mica powder, and the modifier of the modifier-modified mica powder includes 3-phenyl-cyclobutane carboxylic acid and palm wax; The modifier of the modifier-modified mica powder comprises 3-phenyl-cyclobutane carboxylic acid and palm wax in a mass ratio of 1:9 to 9:

1.

2. A heat-resistant biaxially oriented polypropylene film according to claim 1, characterized in that: The mass ratio of the 3-phenyl-cyclobutanecarboxylic acid to the palm wax is 4:6 to 6:

4.

3. A heat-resistant biaxially oriented polypropylene film according to claim 1, characterized in that: The raw materials of the modifier-modified mica powder include the modifier and the mica powder in a mass ratio of 1 to 6:

40.

4. A heat-resistant biaxially oriented polypropylene film according to claim 3, characterized in that: The mass ratio of the modifier to the mica powder is 2.5-4:

40.

5. A heat-resistant biaxially oriented polypropylene film according to any one of claims 1 to 4, characterized in that: The method for preparing the modifier-modified mica powder comprises the following steps: S1, dissolving 3-phenyl-cyclobutanecarboxylic acid in a solvent, adding mica powder, mixing evenly, and drying to obtain pre-modified mica powder; S2. After dissolving palm wax in a solvent, add pre-modified mica powder, mix evenly, and dry to obtain modifier-modified mica powder.

6. The heat-resistant biaxially oriented polypropylene film according to claim 1, characterized in that: The raw materials of the surface layer include the following components in parts by weight: 100 parts of polypropylene resin and 1-3 parts of anti-sticking agent.

7. The heat-resistant biaxially oriented polypropylene film according to claim 1, characterized in that: The antistatic agent includes one or more of the antistatic agent HKD-300 and the antistatic agent MGS-20.

8. The method for preparing a heat-resistant biaxially oriented polypropylene film according to any one of claims 6 or 7, characterized in that: The following steps are involved: The raw materials of the base layer and the raw materials of the surface layer are respectively mixed evenly, and then co-extruded, cast, biaxially stretched, corona treated, and rolled to obtain a heat-resistant biaxially stretched polypropylene film.

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