Antistatic PETG (Polyethylene Terephthalate Glycol) heat shrink film

Abstract

The invention relates to the field of heat shrinkage films, in particular to an antistatic PETG heat shrinkage film. The PETG heat shrink film comprises the following components in parts by weight: 100 parts of PETG resin, 2-6 parts of an anti-adhesion agent, 2-5 parts of a lubricant, 1-5 parts of an antistatic modifier, 1-2 parts of an antioxidant and 0.5-1 part of a light stabilizer. In the preparation process of the PETG heat shrink film, a novel borate antistatic agent is introduced, and the antistatic agent is synthesized by taking tris (2-carboxyethyl) isocyanurate and 4-aminophenylboronic acid pinacol ester as raw materials, so that compared with a traditional antistatic agent, the antistatic property is better, the heat stability is obviously improved, and the service life of the heat shrink film is prolonged. And the phenomenon of local deformation or poor arc-shaped shrinkage of the PETG heat shrinkage film when the PETG heat shrinkage film shrinks at a non-uniform interface is reduced.

Description

Technical Field

[0001] The present invention relates to the field of heat shrinkable films, and particularly to an antistatic PETG heat shrinkable film. Background Art

[0002] A heat shrinkable film refers to a label used to wrap around the outer periphery of a container, and the container includes plastic bottles, glass bottles, etc. The heat shrinkable film has characteristics such as good gloss, conformability, and shrinkability. Moreover, due to the gloss and shrinkability of the heat shrinkable film, the packaging pattern on the container becomes more vivid, which can better highlight the image on the supermarket shelf, generating an unexpected shelf effect, and thus it is widely used for the packaging of containers.

[0003] The existing materials for heat shrinkable films used in labels mainly include polyvinyl chloride (PVC), polyethylene terephthalate - 1,4 - cyclohexanedimethanol ester (PETG), oriented polystyrene (OPS), etc. The PVC heat shrinkable film has characteristics such as high tensile strength, large elongation, good self - adhesiveness, and high transparency. However, it also has the defect of being prone to generating highly toxic dioxins during recycling and poor environmental protection, and thus it is gradually prohibited from being used; the OPS heat shrinkable film has characteristics such as high strength, high rigidity, stable shape, good gloss and transparency, and is also convenient for processing, easy to color, has good printing performance, and extremely high printing resolution. However, it is relatively expensive and requires special solvent - based inks for printing; the PETG heat shrinkable film has characteristics such as non - toxic, odorless, high strength, high heat shrinkage rate, good optical properties, mechanical extensibility, and beautiful packaging effect, which has led to the rapid growth in the use of OPS heat shrinkable film and PETG heat shrinkable film.

[0004] Due to the advantages of high shrinkage rate, good transparency, non - toxic, odorless, and good mechanical properties, the PETG heat shrinkable film has currently successfully replaced the polyvinyl chloride heat shrinkable film and has become the most ideal heat shrinkable packaging material. However, the antistatic performance of the PETG heat shrinkable film is insufficient, and the performance of the currently used antistatic agents on the PETG heat shrinkable film cannot achieve the expected effect; in addition, traditional antistatic agents are prone to uneven dispersion in the PETG heat shrinkable film and have poor thermal stability, which easily leads to local deformation or poor arc - shaped shrinkage during uneven interfacial shrinkage. Summary of the Invention

[0005] Aiming at the problems existing in the prior art, the purpose of the present invention is to provide an antistatic PETG heat shrinkable film.

[0006] The purpose of the present invention is achieved by the following technical solutions: In a first aspect, the present invention provides an antistatic PETG heat shrinkable film, which, calculated by weight parts, comprises the following components: 100 parts of PETG resin, 2 - 6 parts of antiblocking agent, 2 - 5 parts of lubricant, 1 - 5 parts of antistatic modifier, 1 - 2 parts of antioxidant, and 0.5 - 1 part of light stabilizer.

[0007] Preferably, the density of the PETG resin is 1.22 - 1.31 g / cm 3 , more preferably 1.27 g / cm 3 ; the melt index is 8 - 12 g / 10 min (230 °C, 2.16 kg).

[0008] Preferably, the antiblocking agent is surface - silanized silica, with a particle size of 0.5 - 5 μm, more preferably 3 μm.

[0009] Preferably, the preparation method of the surface - silanized silica includes: Mix silica nanopowder, coupling agent KH - 550, and 50 wt% ethanol solution, reflux for 2 - 6 h, then filter and dry to obtain surface - silanized silica; wherein, the mass ratio of silica nanopowder, coupling agent KH - 550, and ethanol solution is 1:0.1 - 0.3:5 - 10.

[0010] Preferably, the lubricant is one or a mixture of zinc stearate, calcium stearate, polyethylene wax, and paraffin.

[0011] Preferably, the preparation method of the antistatic modifier includes: S1. Take dichloromethane as the solvent and add it into a flask, introduce nitrogen as the protective gas, then add tris(2 - carboxyethyl)isocyanurate and N,N’ - dicyclohexylcarbodiimide (DCC), stir in an ice - water bath for 0.5 - 1.5 h, then raise the temperature to room temperature, add N - hydroxysuccinimide (NHS), and stir for 1 - 2 h to obtain an intermediate reaction solution; S2. Slowly add 4 - aminophenylboronic acid pinacol ester to the intermediate reaction solution. After complete addition, stir at room temperature for 4 - 8 h, then remove the solvent under reduced pressure, and purify by silica gel column chromatography to obtain the antistatic modifier.

[0012] Preferably, in the preparation process of the antistatic modifier, the mass ratio of tris(2 - carboxyethyl)isocyanurate, 4 - aminophenylboronic acid pinacol ester, N - hydroxysuccinimide (NHS), N,N’ - dicyclohexylcarbodiimide (DCC), and dichloromethane is 0.2 - 0.4:0.58 - 0.83:0.7 - 0.9:0.4 - 0.6:3 - 8.

[0013] Preferably, in the preparation process of the antistatic modifier, the silica gel column is a C18 column (200 - 300 mesh), and the eluent is a mixed solution obtained by mixing n - hexane and ethyl acetate according to a volume ratio of 2 - 5:1.

[0014] Preferably, the antioxidant is obtained by mixing a primary antioxidant and a secondary antioxidant in a mass ratio of 1:1-4; wherein, the primary antioxidant is one of antioxidant 1010, antioxidant 1076, antioxidant 245, and antioxidant 1098; the secondary antioxidant is antioxidant 168 or antioxidant 126. More preferably, the primary antioxidant is antioxidant 1010 and the secondary antioxidant is antioxidant 168.

[0015] Preferably, the light stabilizer is one or a mixture of UV-770, UV-944, UV-326, UV-328, and UV-1577.

[0016] In a second aspect, the present invention provides a method for preparing an antistatic PETG heat shrinkable film, comprising the following steps: Step 1, weighing each raw material according to parts by weight and drying it to a constant weight in an oven; Step 2, placing each raw material in a high-speed stirrer and stirring evenly to obtain a uniform mixture; Step 3, placing the uniform mixture in a twin-screw extruder and performing melt granulation to obtain a PETG masterbatch; Step 4, placing the PETG masterbatch in a single-screw extruder, casting it into a sheet, and then performing biaxial stretching and film-forming treatment, and finally obtaining an antistatic PETG heat shrinkable film after shaping.

[0017] Preferably, in the said Step 2, the stirring speed is 200-300 rpm and the stirring time is 10-15 min.

[0018] Preferably, in the said Step 3, the melting range is 250-290 °C, the screw rotation speed is 150-200 rpm, and the vacuum exhaust pressure ≤ 100 Pa.

[0019] Preferably, in the said Step 4, casting the sheet means casting the melt into a sheet, and the casting temperature is 25-60 °C.

[0020] Preferably, in the said Step 4, the biaxial stretching and film-forming includes longitudinal stretching (MDO) and transverse stretching (TDO); wherein, the stretching temperature for longitudinal stretching is 80-100 °C and the stretching ratio is 1-3 times; the stretching temperature for transverse stretching is 80-100 °C and the stretching ratio is 3.5-4.5 times; the shaping temperature is 35-50 °C.

[0021] Preferably, in the said Step 4, the thickness of the obtained antistatic PETG heat shrinkable film is 30-50 μm.

[0022] The beneficial effects of the present invention are: 1. In the preparation process of the PETG heat shrinkable film, the present invention introduces a novel borate antistatic agent, which is synthesized using tris (2-carboxyethyl) isocyanurate and 4-aminophenylboronic acid pinacol ester as raw materials. Compared with the traditional antistatic agent, the antistatic agent not only has better antistatic performance, but also has significantly improved thermal stability, thereby reducing the phenomenon of local deformation or poor arc-shaped shrinkage of the PETG heat shrinkable film during uneven interface shrinkage.

[0023] 2. Boric acid ester compounds can be used as environmentally friendly antistatic agents, based on the polar boric acid ester groups therein absorbing moisture to form a conductive layer, thereby reducing the surface resistance. However, the boric acid ester antistatic agents currently on the market (such as triethanolamine borate) are generally poor in thermal stability and have insufficient compatibility with resins, resulting in general antistatic performance. The present invention uses 4-aminophenylboronic acid pinacol ester and tris (2-carboxyethyl) isocyanurate as raw materials, and performs an amidation reaction through a DCC-NHS system. The obtained antistatic agent contains an amide group, a phenylboronic acid pinacol ester structure, and an isocyanurate structure. Compared with traditional boric acid ester antistatic agents, it not only has better compatibility with resins, but also has greatly improved thermal stability, and also improves the phenomenon of poor shrinkage of PETG heat shrinkable film. DETAILED DESCRIPTION

[0024] The technical solution of the present invention is described below through specific examples. It should be understood that the one or more method steps mentioned in the present invention do not exclude the existence of other method steps before and after the combination step or the insertion of other method steps between these explicitly mentioned steps; it should also be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention. Moreover, unless otherwise specified, the numbering of each method step is only a convenient tool for identifying each method step, and is not intended to limit the order of arrangement of each method step or to limit the scope of the present invention. The change or adjustment of the relative relationship thereof shall also be regarded as the scope of the present invention without substantially changing the technical content.

[0025] In order to better understand the above technical scheme, the exemplary embodiments of the present invention are described in more detail below. Although exemplary embodiments of the present invention are shown, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0026] The present invention will be further described below in conjunction with the following examples.

[0027] Example 1 An antistatic PETG heat shrinkable film, calculated by weight, comprises the following components: 100 parts of PETG resin, 4 parts of antiblocking agent, 3 parts of lubricant, 3.5 parts of antistatic modifier, 1 part of antioxidant and 0.6 part of light stabilizer.

[0028] Among them, the density of the PETG resin is 1.27 g / cm 3 ; the melt index is 10 g / 10 min (230 °C, 2.16 kg); the lubricant is zinc stearate; the antioxidant is obtained by mixing antioxidant 1010 and antioxidant 168 in a mass ratio of 1:3; the light stabilizer is UV-944.

[0029] Among them, the antiblocking agent is surface-silanized silica with a particle size of 3 μm, and the preparation method includes: Mix silica nanopowder, coupling agent KH-550 and 50 wt% ethanol solution, reflux for 4 h, then filter and dry to obtain surface-silanized silica; among them, the mass ratio of silica nanopowder, coupling agent KH-550 and ethanol solution is 1:0.2:8.

[0030] Among them, the preparation method of the antistatic modifier includes: S1. Take 5 g of dichloromethane as the solvent and add it to the flask, introduce nitrogen as the protective gas, then add 0.3 g of tris(2-carboxyethyl)isocyanurate and 0.5 g of N,N'-dicyclohexylcarbodiimide (DCC), stir in an ice-water bath for 1 h, then raise the temperature to room temperature, add 0.8 g of N-hydroxysuccinimide (NHS), and stir for 1.5 h to obtain an intermediate reaction solution; S2. Slowly add 0.71 g of 4-aminophenylboronic acid pinacol ester to the intermediate reaction solution. After complete addition, stir at room temperature for 6 h, then remove the solvent under reduced pressure, and perform chromatography on a C18 silica column (250 mesh). The eluent is a mixture of n-hexane and ethyl acetate with a volume ratio of 3:1. After drying, the antistatic modifier is obtained.

[0031] The preparation method of the above-mentioned antistatic PETG heat-shrinkable film includes the following steps: Step 1, weigh each raw material according to the weight parts and dry it to constant weight in an oven; Step 2, place each raw material in a high-speed stirrer and stir at a speed of 300 rpm for 10 min to obtain a uniform mixture; Step 3, place the uniform mixture in a twin-screw extruder, perform melting treatment, the melting range is 250-290 °C, the screw speed is 200 rpm, the vacuum exhaust pressure ≤ 100 Pa, and pelletize to obtain PETG masterbatch; Step 4, placing the PETG masterbatch in a single screw extruder, after casting, the casting temperature is 50°C, and biaxial stretching film treatment is performed; wherein, the stretching temperature of the longitudinal stretching is 90°C, and the stretching ratio is 2 times; the stretching temperature of the transverse stretching is 100°C, and the stretching ratio is 4 times; and then shaping at a temperature of 45°C to obtain a PETG heat shrinkable film with a thickness of 40 μm.

[0032] Example 2 An antistatic PETG heat shrinkable film, calculated by weight, comprises the following components: 100 parts of PETG resin, 2 parts of anti-blocking agent, 5 parts of lubricant, 1 part of antistatic modifier, 1 part of antioxidant and 0.5 parts of light stabilizer.

[0033] Among them, the density of PETG resin is 1.27g / cm 3 The melt index is 10 g / 10 min (230°C, 2.16 kg). The lubricant is calcium stearate. The antioxidant is a mixture of antioxidant 1076 and antioxidant 126 in a mass ratio of 1:1. The light stabilizer is UV-770.

[0034] The anti-adhesion agent is surface silanized silicon dioxide with a particle size of 3 μm, and the preparation method includes: Silica nanopowder, coupling agent KH-550 and 50wt% ethanol solution were mixed, refluxed for 2h, filtered and dried to obtain surface silanized silica; wherein the mass ratio of silica nanopowder, coupling agent KH-550 and ethanol solution was 1:0.1:5.

[0035] Wherein, the preparation method of the antistatic modifier comprises: S1. Take 3 g of dichloromethane as a solvent and add it into a flask. Pass nitrogen as a protective gas, then add 0.2 g of tris(2-carboxyethyl)isocyanurate and 0.4 g of N,N'-dicyclohexylcarbodiimide (DCC), stir in an ice-water bath for 0.5 h, then warm to room temperature, add 0.7 g of N-hydroxysuccinimide (NHS), stir for 1 h, and obtain an intermediate reaction solution; S2. Slowly add 0.58 g of 4-aminophenylboronic acid pinacol ester to the intermediate reaction liquid. After complete addition, stir at room temperature for 4-8 hours, remove the solvent under reduced pressure, and perform chromatography on a C18 silica gel column (250 mesh). The eluent is n-hexane and ethyl acetate in a volume ratio of 2:1. After drying, an antistatic modifier is obtained.

[0036] The preparation method of the above-mentioned antistatic PETG heat shrinkable film comprises the following steps: Step 1, weigh each raw material according to weight, and dry it in an oven to constant weight; Step 2, placing all raw materials in a high-speed stirrer and stirring at a speed of 200 rpm for 10 min to obtain a uniform mixture; Step 3, placing the uniform mixture in a twin-screw extruder, undergoing a melting treatment, the melting range is 250-290° C., the screw speed is 150-200 rpm, the vacuum exhaust pressure is ≤100 Pa, and granulation is performed to obtain PETG masterbatch; Step 4, placing the PETG masterbatch in a single screw extruder, after casting, the casting temperature is 25°C, and biaxial stretching film forming treatment. The stretching temperature of the longitudinal stretching is 80°C, and the stretching ratio is 1 times; the stretching temperature of the transverse stretching is 80°C, and the stretching ratio is 3.5 times; and then shaping at a temperature of 35°C to obtain a PETG heat shrinkable film with a thickness of 30 μm.

[0037] Example 3 An antistatic PETG heat shrinkable film, calculated by weight, comprises the following components: 100 parts of PETG resin, 6 parts of anti-blocking agent, 2 parts of lubricant, 5 parts of antistatic modifier, 2 parts of antioxidant and 1 part of light stabilizer.

[0038] Among them, the density of PETG resin is 1.27g / cm 3 The melt index is 10 g / 10 min (230°C, 2.16 kg). The lubricant is polyethylene wax. The antioxidant is a mixture of antioxidant 1098 and antioxidant 168 in a mass ratio of 1:4. The light stabilizer is UV-328.

[0039] The anti-adhesion agent is surface silanized silicon dioxide with a particle size of 3 μm, and the preparation method includes: Silica nanopowder, coupling agent KH-550 and 50wt% ethanol solution are mixed, refluxed for 2-6h, filtered and dried to obtain surface silanized silica; wherein the mass ratio of silica nanopowder, coupling agent KH-550 and ethanol solution is 1:0.3:10.

[0040] Wherein, the preparation method of the antistatic modifier comprises: S1. Take 3-8g of dichloromethane as a solvent and add it into a flask. Pass nitrogen as a protective gas, then add 0.4g of tris(2-carboxyethyl)isocyanurate and 0.6g of N,N'-dicyclohexylcarbodiimide (DCC), stir in an ice-water bath for 1.5h, then warm to room temperature, add 0.9g of N-hydroxysuccinimide (NHS), stir for 2h to obtain an intermediate reaction solution; S2. Slowly add 0.83 g of 4-aminophenylboronic acid pinacol ester to the intermediate reaction solution. After complete addition, stir at room temperature for 8 h, then remove the solvent under reduced pressure. After chromatography on a C18 silica gel column (250 mesh), the eluent is n-hexane and ethyl acetate with a volume ratio of 5:1. After drying, an antistatic modifier is obtained.

[0041] The preparation method of the above antistatic PETG heat shrinkable film includes the following steps: Step 1. Weigh each raw material by weight parts and dry it to a constant weight in an oven. Step 2. Place each raw material in a high-speed stirrer and stir at a speed of 300 rpm for 15 min to obtain a uniform mixture. Step 3. Place the uniform mixture in a twin-screw extruder, conduct melting treatment, the melting range is 290 °C, the screw speed is 200 rpm, the vacuum exhaust pressure ≤ 100 Pa, and granulate to obtain a PETG masterbatch. Step 4. Place the PETG masterbatch in a single-screw extruder. After casting, the casting temperature is 60 °C, and then conduct biaxial stretching and film-forming treatment. Among them, the stretching temperature for longitudinal stretching is 100 °C, and the stretching ratio is 3 times; the stretching temperature for transverse stretching is 100 °C, and the stretching ratio is 4.5 times; then it is shaped at 50 °C to obtain a PETG heat shrinkable film with a thickness of 50 μm.

[0042] Comparative Example 1 A PETG heat shrinkable film, different from Example 1 in that the antistatic modifier is replaced with triethanolamine borate, and other components and preparation methods are the same as those in Example 1.

[0043] Comparative Example 2 A PETG heat shrinkable film, different from Example 1 in that the antistatic modifier is replaced with 4-aminophenylboronic acid pinacol ester, and other components and preparation methods are the same as those in Example 1.

[0044] Comparative Example 3 A PETG heat shrinkable film, different from Example 1 in that the antistatic modifier is replaced with tris(2-carboxyethyl)isocyanurate, and other components and preparation methods are the same as those in Example 1.

[0045] Experimental detection The heat shrinkage rate, strength and antistatic properties of the PETG heat shrinkable films prepared in Example 1 and Comparative Examples 1-3 were detected.

[0046] Among them, the detection reference standard for tensile strength is GB / T 19787-2005 (tensile speed: 50 mm / min); the detection reference standard for heat shrinkage rate and shrinkage stress is ISO 14616 (hot air treatment at 110 °C for 20 seconds); the detection reference standard for surface resistivity is ASTM D257 (test voltage: 500 V DC (conventional value)).

[0047] The results of the detection are shown in Table 1 below: Table 1 Detection Results of PETG Heat Shrinkable Film

[0048] It can be seen that, compared with other comparative examples, the PETG heat shrinkable film prepared in Example 1 of the present invention has a transverse tensile strength of 168 MPa, a longitudinal tensile strength of 57 MPa, a shrinkage stress of 6.4 N / 15 mm, and a transverse heat shrinkage rate of 83%. This shows that it has high mechanical strength and excellent thermal stability, and can largely avoid the phenomenon of poor shrinkage. In addition, compared with Comparative Example 1, the PETG heat shrinkable film prepared in Example 1 has a smaller surface resistivity, indicating that its antistatic performance is also more excellent.

[0049] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "example", "specific example", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms should not be understood as necessarily referring to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine the different embodiments or examples described in this specification.

[0050] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. An antistatic PETG heat shrinkable film, characterized in that, Calculated by weight parts, it includes the following components: 100 parts of PETG resin, 2 - 6 parts of antiblocking agent, 2 - 5 parts of lubricant, 1 - 5 parts of antistatic modifier, 1 - 2 parts of antioxidant and 0.5 - 1 part of light stabilizer; Among them, the antiblocking agent is surface - silanized silica; the antistatic modifier is a product obtained by amidation reaction of tris(2 - carboxyethyl)isocyanurate and 4 - aminophenylboronic acid pinacol ester.

2. The antistatic PETG heat shrinkable film according to claim 1, wherein The preparation method of the surface - silanized silica includes: Mix silica nanopowder, coupling agent KH - 550 and 50wt% ethanol solution, after refluxing for 2 - 6h, filter and dry to obtain surface - silanized silica; wherein, the mass ratio of silica nanopowder, coupling agent KH - 550 and ethanol solution is 1:0.1 - 0.3:5 - 10.

3. An antistatic PETG heat shrinkable film according to claim 1, wherein The lubricant is one or a mixture of zinc stearate, calcium stearate, polyethylene wax, paraffin wax.

4. An antistatic PETG heat shrinkable film according to claim 1, characterized in that, The preparation method of the antistatic modifier includes: S1. Take dichloromethane as the solvent and add it into the flask, introduce nitrogen as the protective gas, then add tris(2 - carboxyethyl)isocyanurate and N,N’ - dicyclohexylcarbodiimide, stir in an ice - water bath for 0.5 - 1.5h, then raise the temperature to room temperature, add N - hydroxysuccinimide, and stir for 1 - 2h to obtain an intermediate reaction solution; S2. Slowly add 4 - aminophenylboronic acid pinacol ester to the intermediate reaction solution. After complete addition, stir at room temperature for 4 - 8h, then remove the solvent under reduced pressure, and purify by silica gel column chromatography to obtain the antistatic modifier.

5. An antistatic PETG heat shrinkable film according to claim 4, characterized in that, In the preparation process of the antistatic modifier, the mass ratio of tris(2 - carboxyethyl)isocyanurate, 4 - aminophenylboronic acid pinacol ester, N - hydroxysuccinimide, N,N’ - dicyclohexylcarbodiimide and dichloromethane is 0.2 - 0.4:0.58 - 0.83:0.7 - 0.9:0.4 - 0.6:3 - 8.

6. An antistatic PETG heat shrinkable film according to claim 1, wherein, The antioxidant is obtained by mixing a primary antioxidant and a secondary antioxidant in a mass ratio of 1:1 - 4; among them, the primary antioxidant is one of antioxidant 1010, antioxidant 1076, antioxidant 245, antioxidant 1098; the secondary antioxidant is antioxidant 168 or antioxidant 126.

7. An antistatic PETG heat shrinkable film according to claim 1, characterized in that, The light stabilizer is one or a mixture of UV - 770, UV - 944, UV - 326, UV - 328, UV - 1577.

8. A method for preparing the antistatic PETG heat shrinkable film according to claim 1, characterized in that, It includes the following steps: Step 1, weigh each raw material according to weight parts and dry it to constant weight in an oven; Step 2, place each raw material in a high - speed stirrer and stir evenly to obtain a uniform mixture; Step 3, place the uniform mixture in a twin - screw extruder and perform melt granulation to obtain PETG masterbatch; Step 4, place the PETG masterbatch in a single - screw extruder, after casting, perform biaxial stretching and film - forming treatment, and obtain an antistatic PETG heat - shrinkable film after shaping.

9. The preparation method of an antistatic PETG heat shrinkable film according to claim 8, characterized in that, In Step 3, the melting range is 250 - 290°C, the screw speed is 150 - 200rpm, and the vacuum exhaust pressure ≤ 100Pa.

10. The preparation method of an antistatic PETG heat shrinkable film according to claim 8, wherein, In the step 4, the biaxial stretching film formation includes longitudinal stretching and transverse stretching; wherein, the stretching temperature for longitudinal stretching is 80-100 °C, and the stretching ratio is 1-3 times; the stretching temperature for transverse stretching is 80-100 °C, and the stretching ratio is 3.5-4.5 times; the setting temperature is 35-50 °C.

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