A toughened and reinforced PETG film and its preparation method and use

Abstract

The present invention relates to the technical field of reinforced and toughened composite materials, and in particular to a toughened and reinforced PETG film and a preparation method and use thereof. The method firstly mixes fine PETG powder with an auxiliary agent to pre-prepare a PETG masterbatch, and then melt-extrudes and granulates the prepared masterbatch, PETG powder and SEBS-g-MAH to finally obtain a reinforced and toughened PETG film with excellent performance, thereby solving the disadvantages of poor uniformity of the modified material and performance differences at different positions.

Description

Technical Field

[0001] The invention relates to the technical field of reinforced and toughened composite materials, and in particular to a toughened and reinforced PETG film, a preparation method and application thereof. Background Art

[0002] Polyethylene terephthalate-1,4-cyclohexane dimethyl ester (PETG) has the advantages of high transparency and good glossiness, and is a transparent and environmentally friendly plastic. PETG has the advantages of high impact strength, antistatic, excellent chemical resistance, hydrolysis resistance, good fluidity, strong tinting power, easy molding and processing, and low cost. However, the mechanical properties of PETG, such as wear resistance, tensile strength, and toughness, are lower than those of PC.

[0003] The prior art obtains a non-toxic, relatively aging-resistant and wear-resistant PETG card base by heating, stirring, melting, five-roll sheeting, and desorption stretching of CS2 and ADD2 type PETG and titanium dioxide in a certain proportion. There is also a method of mixing PETG resin, vinyl chloride, microcrystalline wax, etc. in a certain proportion and melt extruding to obtain a modified PETG material that does not hydrolyze or deform at 220°C. There is also a method of mixing PETG, PPT, and POE-g-MAH and melt extruding them, which combines the advantages of PPT and PETG and has high impact strength, excellent heat resistance and aging resistance.

[0004] In summary, the prior art generally melt-blends PETG with a modified elastomer to prepare a modified PETG material with better performance. Commonly used modified elastomers include PP-g-MAH, POE-g-MAH, and PE-g-MAH. Although the effect can be improved to a certain extent, there are often disadvantages such as poor uniformity of the modified material and performance differences at different locations.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The first purpose of the present invention is to provide a method for preparing a toughened and reinforced PETG film. In the method, fine PETG powder is first mixed with an additive to pre-prepare a PETG masterbatch, and then the prepared masterbatch, PETG powder and toughening agent are melt-extruded and granulated to finally obtain a reinforced and toughened PETG material with excellent performance, thereby solving the shortcomings of poor uniformity of the modified material and performance differences at different positions.

[0007] The second object of the present invention is to provide the toughened and reinforced PETG film as described above, which has both good strength and good toughness and good processability.

[0008] The third object of the present invention is to provide the toughened and reinforced PETG film as described above which can be used as a substrate for preparing documents.

[0009] In order to achieve the above-mentioned purpose of the present invention, the following technical solutions are particularly adopted:

[0010] The present invention provides a method for preparing a toughened and reinforced PETG film, comprising the following steps:

[0011] (1) mixing and granulating the first PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture, antioxidant and anti-UV agent to obtain PETG masterbatch;

[0012] (2) The PETG masterbatch obtained in step (1), the second PETG powder, and SEBS-g-MAH are mixed, melt-extruded, rolled, shaped, and then stretched to obtain a PETG film.

[0013] Preferably, in step (1), the mass ratio of the first PETG powder, the titanium dioxide, the microcrystalline wax-calcium stearate mixture, the antioxidant and the anti-UV agent is 15-25:8-16:0.3-0.8:0.4-0.8:0.3-0.5.

[0014] Preferably, the microcrystalline wax-calcium stearate mixture consists of microcrystalline wax and calcium stearate in a mass ratio of 3-5:1-3.

[0015] Preferably, the particle size of the PETG powder is 2 mm to 6 mm.

[0016] Preferably, in step (1), the mixture is stirred at 80-90° C. for 15-20 min.

[0017] Preferably, the antioxidant includes at least one of antioxidant 1010, antioxidant 1076, antioxidant 245, antioxidant 1330, antioxidant 3114, and antioxidant 1098.

[0018] Preferably, the anti-UV agent includes at least one of UV-531, UV-326, UV-770, and UV-360.

[0019] Preferably, in step (1), the granulation is carried out by a twin-screw extruder, and the temperature settings of each temperature zone of the twin-screw extruder are 220-225°C, 225-230°C, 235-240°C and 245-250°C respectively; the rotation speed of the twin-screw extruder is 100-110r / min.

[0020] Preferably, in step (2), the mass ratio of the PETG masterbatch, the second PETG powder and the SEBS-g-MAH is: 3-5: 6-9: 0.5-1.5.

[0021] Preferably, in step (2), the melt extrusion is carried out using a twin-screw extruder, and the temperature settings of each temperature zone of the twin-screw extruder are 210-215°C, 220-225°C, 235-245°C and 250-255°C respectively; the rotation speed of the twin-screw extruder is 110-120r / min.

[0022] Preferably, the rolling is performed three times, and the temperatures of each rolling are 60-65°C, 30-35°C and 30-35°C respectively.

[0023] The toughened and reinforced PETG film sheet is prepared by the method for preparing the toughened and reinforced PETG film sheet provided by the present invention.

[0024] Preferably, the toughened and reinforced PETG film has a thickness of 50 to 350 μm.

[0025] The toughened and reinforced PETG film provided by the present invention is used as a substrate in the process of preparing certificates.

[0026] Compared with the prior art, the present invention has the following beneficial effects:

[0027] (1) The method for preparing the toughened and reinforced PETG film provided by the present invention comprises the following steps: firstly, fine PETG powder is mixed with an additive to prepare a PETG masterbatch, and then the prepared masterbatch, PETG and a toughening agent are melt-extruded and granulated to finally obtain a toughened and reinforced PETG film with excellent performance, thereby solving the disadvantages of poor uniformity of the modified material and performance differences at different positions.

[0028] (2) The method for preparing the toughened and reinforced PETG film provided by the present invention can improve the toughness of PETG by modifying PETG with SEBS-g-MAH.

[0029] (3) The preparation method of the toughened and reinforced PETG film provided by the present invention can improve the anti-ultraviolet performance of the PETG film by adding titanium dioxide and anti-UV agent, and improve its tensile strength to a certain extent.

[0030] (4) The method for preparing the toughened and reinforced PETG film provided by the present invention uses an internal-external lubricant composite system combining microcrystalline wax and calcium stearate.

[0031] (5) The toughened and reinforced PETG film provided by the present invention has good processability and toughness, and also has good strength performance and UV resistance. DETAILED DESCRIPTION

[0032] The technical scheme of the present invention will be clearly and completely described below in conjunction with specific embodiments, but it will be appreciated by those skilled in the art that the following described embodiments are part of embodiments of the present invention, rather than all embodiments, and are only used to illustrate the present invention, and should not be considered as limiting the scope of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative work, all belong to the scope of protection of the present invention. If specific conditions are not indicated in the embodiments, they are carried out according to normal conditions or conditions recommended by the manufacturer. If the manufacturer is not indicated in the reagents or instruments used, they are all conventional products that can be purchased commercially.

[0033] The method for preparing a toughened and reinforced PETG film provided by an embodiment of the present invention comprises the following steps: firstly, fine PETG powder is mixed with an auxiliary agent to prepare a PETG masterbatch, and then the prepared masterbatch, PETG and a toughening agent are melt-extruded and granulated to finally obtain a toughened and reinforced PETG film with excellent performance, thereby solving the disadvantages of poor uniformity of the modified material and performance differences at different positions. The method for preparing a toughened and reinforced PETG film comprises: (1) mixing and granulating a first PETG powder, titanium dioxide, a microcrystalline wax-calcium stearate mixture, an antioxidant and an anti-UV agent to obtain a PETG masterbatch; (2) mixing, melt-extruding, rolling, shaping and then stretching the PETG masterbatch obtained in step (1), a second PETG powder and SEBS-g-MAH to obtain a PETG film.

[0034] The particle size of the PETG powder is 2 mm to 6 mm, for example, any point value among 2 mm, 3 mm, 4 mm, 5 mm, and 6 mm, or a range value consisting of any two point values. For example, a high-speed grinding mill is used to grind the PETG powder to obtain a PETG powder of appropriate particle size, which is conducive to uniform dispersion of PETG and obtaining a PETG masterbatch with uniform properties.

[0035] In one embodiment, in step (1), the mass ratio of the first PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture, antioxidant and anti-UV agent is 15-25:8-16:0.3-0.8:0.4-0.8:0.3-0.5, for example, 20:10:0.5:0.6:0.4, 15:8:0.3:0.4:0.3, 25:16:0.8:0.8:0.5, 22:12:0.6:0.5:0.4, or a ratio range thereof.

[0036] Among them, titanium dioxide has both UV resistance and the function of improving the overall strength of the material. The microcrystalline wax-calcium stearate mixture is a composition composed of microcrystalline wax and calcium stearate in a mass ratio of 3 to 5:1 to 3, such as any ratio or any range of two ratios of 3:1, 3:2, 4:1, 4:2, 4:3, 5:1, 5:2, 5:3, preferably, the proportion of microcrystalline wax is slightly higher than that of calcium stearate. Furthermore, microcrystalline wax refers to the wax paste obtained by solvent refining, solvent dewaxing, or wax freezing crystallization, squeeze dewaxing from the lubricating oil fraction obtained from crude oil distillation, and then solvent deoiling or sweat deoiling, and supplementary refining to obtain flaky or needle-shaped crystals.

[0037] Among them, the antioxidant includes at least one of antioxidant 1010, antioxidant 1076, antioxidant 245, antioxidant 1330, antioxidant 3114, and antioxidant 1098.

[0038] Wherein, the anti-UV agent includes at least one of UV-531, UV-326, UV-770 and UV-360.

[0039] In one embodiment, in step (1), the mixture is stirred at 80 to 90° C. (e.g., any one of 80, 85, and 90° C. or a range consisting of any two of them) for 15 to 20 min (e.g., any one of 15, 18, and 20 min or a range consisting of any two of them).

[0040] In one embodiment, in step (1), granulation is performed by conventional conventional techniques, including but not limited to extrusion granulation using a twin-screw extruder. Further, the temperature settings of each temperature zone of the twin-screw extruder are successively increased to 220-225°C, 225-230°C, 235-240°C and 245-250°C, such as 220°C, 225°C, 235°C, 245°C, or 225°C, 230°C, 240°C, 250°C; the speed of the twin-screw extruder is 100-110r / min (e.g., any point value among 100, 105, 110r / min or a range value consisting of any two point values).

[0041] In one embodiment, in step (2), the mass ratio of the PETG masterbatch, the second PETG powder and the SEBS-g-MAH is: 3-5:6-9:0.5-1.5, for example, any ratio of 3:6:1, 4:8:1, 5:9:1, 3:6:0.5, 3:6:0.7, 3:6:0.9, 3:6.6:1.1, 3:6.6:1.5 or any two ratios forming a range value.

[0042] In one embodiment, in step (2), the melt extrusion adopts conventional technical means, including but not limited to a twin-screw extruder. Further, the temperature settings of each temperature zone of the twin-screw extruder are 210-215°C, 220-225°C, 235-245°C and 250-255°C, for example, 210°C, 220°C, 235°C, 250°C, or 215°C, 225°C, 240°C, 255°C; the speed of the twin-screw extruder is 110-120r / min (for example, any point value among 110, 115, 120r / min or a range value composed of any two point values).

[0043] In one embodiment, the rolling is preferably performed three times, and the temperatures of each rolling are 60-65°C, 30-35°C and 30-35°C, for example, 65°C, 35°C, 35°C, or 60°C, 30°C, 30°C. The material is rolled multiple times to achieve uniformity. After shaping, the material is stretched into a film, and the thickness of the film is 50-350 μm.

[0044] The toughened and reinforced PETG film sheet prepared by the method for preparing the toughened and reinforced PETG film sheet provided by the present invention has good strength and toughness, and also good processability, and can be used as a substrate for preparing certificates (including legal certificates).

[0045] In one embodiment, the thickness of the toughened and reinforced PETG film is 50 to 350 μm, for example, any value among 50 μm, 100 μm, 150 μm, 200 μm, 250 μm, 300 μm, and 350 μm, or a range consisting of any two values.

[0046] Example 1

[0047] The method for preparing the toughened and reinforced PETG film provided in this embodiment comprises the following steps:

[0048] (1) PETG raw material processing: Place the PETG pellets in a grinder and grind them at high speed for 30 minutes to obtain PETG powder with a particle size of 3 mm.

[0049] (2) Preparation of PETG masterbatch premix: 3 mm PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture (the mass ratio of microcrystalline wax to calcium stearate is 3:2), antioxidant 1010, and UV inhibitor UV-531 are mixed in a mass ratio of 20:10:0.5:0.6:0.4, placed in a blender, and stirred at 90° C. for 15 min to obtain a PETG masterbatch premix.

[0050] (3) Preparation of PETG masterbatch: The PETG masterbatch premix was extruded and granulated by a twin-screw extruder to obtain PETG masterbatch. The temperature settings of each temperature zone of the twin-screw extruder were 220, 225, 235 and 245° C., respectively, and the speed was set to 100 r / min.

[0051] (4) The prepared PETG masterbatch, 3 mm PETG powder, and SEBS-g-MAH were placed in a twin-screw extruder in a mass ratio of 30:62:10 for melt extrusion, and the melt flowing out of the T-die was subjected to three-roll calendering and shaping, and then a 100 μm film was made at a certain film drawing rate to obtain a PETG film sheet.

[0052] The temperature zones of the extruder were set at 210, 220, 235 and 250°C, the speed was set at 120 r / min, and the temperatures of the three-roll calender were set at 65, 35 and 35°C.

[0053] Example 2

[0054] The method for preparing the toughened and reinforced PETG film provided in this embodiment comprises the following steps:

[0055] (1) PETG raw material processing: Place the PETG pellets in a grinder and grind them at high speed for 20 minutes to obtain 2mm PETG powder.

[0056] (2) Preparation of PETG masterbatch premix: 2 mm PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture (the mass ratio of microcrystalline wax to calcium stearate is 3:2), antioxidant 1010, and UV inhibitor UV-531 are mixed in a mass ratio of 20:10:0.5:0.6:0.4, placed in a blender, and stirred at 90° C. for 20 min to obtain a PETG masterbatch premix.

[0057] (3) Preparation of PETG masterbatch: The PETG masterbatch premix was extruded and granulated by a twin-screw extruder to obtain PETG masterbatch. The temperature settings of each temperature zone of the twin-screw extruder were 220, 225, 235 and 245° C., respectively, and the speed was set to 100 r / min.

[0058] (4) The prepared PETG masterbatch, 2 mm PETG powder, and SEBS-g-MAH were placed in a twin-screw extruder in a mass ratio of 30:64:10 for melt extrusion, and the melt flowing out of the T-die was subjected to three-roll calendering and shaping, and then a 100 μm film was made at a certain film drawing rate to obtain a PETG film sheet.

[0059] The temperature zones of the extruder were set at 210, 220, 235 and 250°C, the speed was set at 120 r / min, and the temperatures of the three-roll calender were set at 65, 35 and 35°C.

[0060] Example 3

[0061] The method for preparing the toughened and reinforced PETG film provided in this embodiment comprises the following steps:

[0062] (1) PETG raw material processing: Place the PETG pellets in a grinder and grind them at high speed for 25 minutes to obtain 6mm PETG powder.

[0063] (2) Preparation of PETG masterbatch premix: 6 mm PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture (the mass ratio of microcrystalline wax to calcium stearate is 3:2), antioxidant 1010, and UV inhibitor UV-531 are mixed in a mass ratio of 20:10:0.5:0.6:0.4, placed in a blender, and stirred at 90°C for 20 min to obtain a PETG masterbatch premix.

[0064] (3) Preparation of PETG masterbatch: The PETG masterbatch premix was extruded and granulated by a twin-screw extruder to obtain PETG masterbatch. The temperature settings of each temperature zone of the twin-screw extruder were 220, 225, 235 and 245° C., respectively, and the speed was set to 100 r / min.

[0065] (4) The prepared PETG masterbatch, 6 mm PETG powder, and SEBS-g-MAH were placed in a twin-screw extruder in a mass ratio of 30:66:10 for melt extrusion. The melt flowing out of the T-die was subjected to three-roll calendering and shaping, and then a 100 μm film was made at a certain film drawing rate to obtain a PETG film sheet.

[0066] The temperature zones of the extruder were set at 210, 220, 235 and 250°C, the speed was set at 120 r / min, and the temperatures of the three-roll calender were set at 65, 35 and 35°C.

[0067] Example 4

[0068] The method for preparing the toughened and reinforced PETG film provided in this embodiment comprises the following steps:

[0069] (1) PETG raw material processing: Place the PETG pellets in a grinder and grind them at high speed for 20 minutes to obtain 4 mm PETG powder.

[0070] (2) Preparation of PETG masterbatch premix: 4 mm PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture (the mass ratio of microcrystalline wax to calcium stearate is 3:2), antioxidant 1010, and UV inhibitor UV-531 are mixed in a mass ratio of 20:10:0.5:0.6:0.4, placed in a blender, and stirred at 90° C. for 20 min to obtain a PETG masterbatch premix.

[0071] (3) Preparation of PETG masterbatch: The PETG masterbatch premix was extruded and granulated by a twin-screw extruder to obtain PETG masterbatch. The temperature settings of each temperature zone of the twin-screw extruder were 220, 225, 235 and 245° C., respectively, and the speed was set to 100 r / min.

[0072] (4) The prepared PETG masterbatch, 4 mm PETG powder, and SEBS-g-MAH were placed in a twin-screw extruder in a mass ratio of 30:68:10 for melt extrusion. The melt flowing out of the T-die was subjected to three-roll calendering and shaping, and then a 100 μm film was made at a certain film drawing rate to obtain a PETG film sheet.

[0073] The temperature zones of the extruder were set at 210, 220, 235 and 250°C, the speed was set at 120 r / min, and the temperatures of the three-roll calender were set at 65, 35 and 35°C.

[0074] Example 5

[0075] The preparation method of the toughened and reinforced PETG film provided in this embodiment is basically the same as that in Example 4, except that in step (4), the mass ratio of PETG masterbatch, PETG, and SEBS-g-MAH is 30:70:10.

[0076] Example 6

[0077] The preparation method of the toughened and reinforced PETG film provided in this embodiment is basically the same as that in Example 4, except that in step (4), the mass ratio of PETG masterbatch, PETG, and SEBS-g-MAH is 30:66:7.

[0078] Example 7

[0079] The preparation method of the toughened and reinforced PETG film provided in this embodiment is basically the same as that in Example 4, except that in step (4), the mass ratio of PETG masterbatch, PETG, and SEBS-g-MAH is 30:66:8.

[0080] Example 8

[0081] The preparation method of the toughened and reinforced PETG film provided in this embodiment is basically the same as that in Example 4, except that in step (4), the mass ratio of PETG masterbatch, PETG, and SEBS-g-MAH is 30:66:9.

[0082] Example 9

[0083] The preparation method of the toughened and reinforced PETG film provided in this embodiment is basically the same as that in Example 4, except that in step (4), the mass ratio of PETG masterbatch, PETG, and SEBS-g-MAH is 30:66:11.

[0084] Example 10

[0085] The method for preparing the toughened and reinforced PETG film provided in this embodiment comprises the following steps:

[0086] (1) PETG raw material processing: Place the PETG pellets in a grinder and grind them at high speed for 20 minutes to obtain 4 mm PETG powder.

[0087] (2) Preparation of PETG masterbatch premix: 4 mm PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture (the mass ratio of microcrystalline wax to calcium stearate is 5:3), antioxidant 1010, and UV inhibitor UV-531 are mixed in a mass ratio of 25:8:0.8:0.8:0.5, placed in a blender, and stirred at 80° C. for 15 min to obtain a PETG masterbatch premix.

[0088] (3) Preparation of PETG masterbatch: The PETG masterbatch premix was extruded and granulated through a twin-screw extruder to obtain PETG masterbatch. The temperature settings of each temperature zone of the twin-screw extruder were 225, 230, 240 and 250° C., respectively, and the rotation speed was set to 110 r / min.

[0089] (4) The prepared PETG masterbatch, 4 mm PETG powder, and SEBS-g-MAH were placed in a twin-screw extruder in a mass ratio of 30:68:15 for melt extrusion. The melt flowing out of the T-die was subjected to three-roll calendering and shaping, and then a 300 μm film was made at a certain film drawing rate to obtain a PETG film sheet.

[0090] The temperature zones of the extruder were set at 215, 225, 240 and 255°C, the speed was set at 110 r / min, and the temperatures of the three-roll calender were set at 60, 30 and 30°C.

[0091] Comparative Example 1

[0092] The preparation method of the toughened and reinforced PETG film provided in this comparative example is basically the same as that of Example 10, except that the PETG masterbatch is not added in step (4), and the PETG masterbatch is mixed with PETG powder, titanium dioxide, microcrystalline wax-calcium stearate mixture (the mass ratio of microcrystalline wax to calcium stearate is 3:2), antioxidant 1010 and anti-UV agent UV-531 in a mass ratio of 20:10:0.5:0.6:0.4 in step (2).

[0093] Comparative Example 2

[0094] The preparation method of the toughened and reinforced PETG film provided in this comparative example is basically the same as that of Example 10, except that titanium dioxide is not added to the PETG masterbatch premix in step (2), but is replaced by an equal mass of PETG powder.

[0095] Comparative Example 3

[0096] The preparation method of the toughened and reinforced PETG film provided in this comparative example is basically the same as that of Example 10, except that SEBS-g-MAH is not added in step (4), but is replaced by the PETG masterbatch prepared in step (2) of equal mass.

[0097] Experimental Example 1 PETG film performance test

[0098] The performance of the membranes obtained in the examples and comparative examples was tested, and the results of tensile strength were shown in Table 1, and the results of impact strength were shown in Table 2.

[0099] Table 1 Tensile strength test results

[0100] Tensile strength / Mpa Example 1 54.3 Example 2 54.8 Example 3 55.0 Example 4 55.6 Example 5 56.2 Example 10 57.2 Comparative Example 1 52.3 Comparative Example 2 48 Comparative Example 3 50.2

[0101] Table 2 Impact strength test results

[0102] Impact strength / (J / m) Example 3 99 Example 4 98 Example 8 94 Example 9 107 Example 10 120 Comparative Example 1 86 Comparative Example 2 88 Comparative Example 3 80

[0103] As can be seen from Table 1, by comparing the results of Examples 1-5, it can be found that as the PETG content increases, the material strength is improved, but the effect is not obvious. Therefore, the present application obtains a high-strength PETG film by reasonably adjusting the combination and proportion of each component, rather than simply increasing the PETG content to achieve increased strength.

[0104] It can be seen from Table 2 that, compared with the embodiments and comparative examples, as the content of SEBS-g-MAH increases, the toughness of the material is significantly improved.

[0105] In addition, by comparing the results of Example 10, Comparative Example 1 and Comparative Example 2, it is found that the addition of titanium dioxide can increase the tensile strength of the material and can have a good reinforcement effect.

[0106] Although the present invention has been illustrated and described with specific embodiments, it should be appreciated that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Those skilled in the art should understand that the technical solutions described in the above embodiments may be modified, or some or all of the technical features thereof may be replaced by equivalents without departing from the spirit and scope of the present invention. However, these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. Therefore, this means that all such replacements and modifications within the scope of the present invention are included in the appended claims.

Claims

1. A method for preparing a toughened and reinforced PETG film, characterized in that: The following steps are involved: (1) mixing and granulating a first PETG powder, titanium dioxide, a microcrystalline wax-calcium stearate mixture, an antioxidant and an anti-UV agent to obtain a PETG masterbatch; (2) mixing, melt-extruding, rolling, shaping, and then stretching the PETG masterbatch, the second PETG powder, and SEBS-g-MAH obtained in step (1) to obtain a PETG film; In step (1), the mass ratio of the first PETG powder, the titanium dioxide, the microcrystalline wax-calcium stearate mixture, the antioxidant and the anti-UV agent is 25:8:0.8:0.8:0.5; The microcrystalline wax-calcium stearate mixture is composed of microcrystalline wax and calcium stearate in a mass ratio of 5:3; The particle size of the first PETG powder and / or the second PETG powder is 2 to 6 mm; In step (2), the mass ratio of the PETG masterbatch, the second PETG powder and the SEBS-g-MAH is 30:68:

15.

2. The method for preparing the toughened and reinforced PETG film according to claim 1, characterized in that: In step (1), the mixture is stirred at 80 to 90° C. for 15 to 20 minutes.

3. The method for preparing the toughened and reinforced PETG film according to claim 1, characterized in that: In step (1), the antioxidant includes at least one of antioxidant 1010, antioxidant 1076, antioxidant 245, antioxidant 1330, antioxidant 3114, and antioxidant 1098; and / or; The anti-UV agent includes at least one of UV-531, UV-326, UV-770, UV-360, and UV-1577.

4. The method for preparing the toughened and reinforced PETG film according to claim 1, characterized in that: In step (1), the granulation is carried out by a twin-screw extruder, and the temperature settings of each temperature zone of the twin-screw extruder are 220-225°C, 225-230°C, 235-240°C and 245-250°C respectively; the rotation speed of the twin-screw extruder is 100-110r / min.

5. The method for preparing the toughened and reinforced PETG film according to claim 1, characterized in that: In step (2), the melt extrusion is carried out by a twin-screw extruder, and the temperature settings of each temperature zone of the twin-screw extruder are 210-215°C, 220-225°C, 235-245°C and 250-255°C respectively; the rotation speed of the twin-screw extruder is 110-120r / min.

6. The method for preparing the toughened and reinforced PETG film according to claim 1, characterized in that: In step (2), the rolling is performed three times, and the temperatures of each rolling are 60-65°C, 30-35°C and 30-35°C respectively.

7. A toughened and reinforced PETG film sheet obtained according to the method for preparing a toughened and reinforced PETG film sheet according to any one of claims 1 to 6.

8. The toughened and reinforced PETG film according to claim 7, wherein the thickness of the toughened and reinforced PETG film is 50 to 350 μm.

9. The toughened and reinforced PETG film according to claim 7 is used as a substrate in the process of preparing certificates.