An anti-UV and antistatic polyolefin elastomer composite film and its preparation method

Abstract

This invention relates to the field of polymer material modification technology, specifically disclosing an anti-UV and antistatic polyolefin elastomer composite film and its preparation method. The preparation method of the composite film of this invention includes the following steps: (1) dissolving maleic anhydride-grafted polyolefin elastomer in 80%-90% of the total organic solvent and stirring until it becomes a colorless and transparent liquid; (2) mixing nano zinc oxide, aminated multi-walled carbon nanotubes, carbon black, polyethylene glycol and the remaining organic solvent, dispersing them evenly, and then adding them to the colorless and transparent liquid obtained in (1), stirring to obtain a mixture; (3) inverting the mixture obtained in (2) onto a flat plate and spreading it out, cooling and shaping it, and then drying it to obtain the anti-UV and antistatic polyolefin elastomer composite film. This invention achieves the enhancement of antistatic and anti-UV functions through polar modification of POE-g-MAH, synergistic design of functional fillers and solution dispersion, while retaining the original mechanical properties of POE.

Description

Technical Field

[0001] This invention relates to the field of polymer material modification technology, specifically to an anti-UV and antistatic polyolefin elastomer composite film and its preparation method. Background Technology

[0002] Polyolefin elastomers (POEs) possess excellent flexibility, weather resistance, and processability, making them widely used in automotive parts, electronic packaging, and outdoor building materials. However, pure POE is a non-polar polymer with low surface energy and poor conductivity. In dry environments or under frictional conditions, it easily accumulates static electricity, attracting dust and oil, and may even trigger electrostatic discharge, affecting product safety. Furthermore, the lack of UV-resistant functional groups in the POE molecular chain makes it prone to degradation when exposed to sunlight for extended periods, leading to decreased mechanical properties and surface aging and cracking, thus limiting its long-term application in outdoor settings.

[0003] To address this issue, existing technologies often modify POE or grafted POE by adding UV absorbers, mainly falling into two categories: organic and inorganic. While organic UV absorbers have good dispersibility, they suffer from poor photostability and are prone to migration and precipitation after long-term use. Inorganic UV absorbers include ZnO and TiO2. However, a single inorganic UV absorber is insufficient to achieve full-band UV shielding. Existing composite systems lack effective means to control the dispersibility of UV absorbers, making it difficult to balance UV resistance and mechanical properties, thus limiting their practical applications. Summary of the Invention

[0004] To address the problems of limited antistatic / UV protection functions, poor filler dispersion, insufficient functional stability, and decreased mechanical properties in existing POE modifications, this invention aims to provide an anti-UV and antistatic polyolefin elastomer composite film and its preparation method. This invention achieves enhanced antistatic and UV protection functions while retaining the original mechanical properties of POE through polar modification of maleic anhydride-grafted polyolefin elastomer (POE-g-MAH), synergistic design of functional fillers, and solution dispersion.

[0005] To achieve the above objectives, the present invention adopts the following technical solution: A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: (1) Dissolve maleic anhydride-grafted polyolefin elastomer in 80%-90% of the total organic solvent and stir until it becomes a colorless and transparent liquid. (2) Mix nano zinc oxide, aminated multi-walled carbon nanotubes, carbon black, polyethylene glycol and the remaining organic solvent, disperse evenly and then add to the colorless and transparent liquid obtained in step (1), stir to obtain a mixture; (3) The mixture obtained in (2) is inverted onto a flat plate and spread out. After cooling and solidification at room temperature, it is dried to obtain the UV-resistant and antistatic polyolefin elastomer composite film.

[0006] The organic solvent in steps (1) and (2) is tetrahydrofuran.

[0007] The nano zinc oxide accounts for 1% of the mass of the maleic anhydride-grafted polyolefin elastomer, the aminated multi-walled carbon nanotubes account for 1% of the mass of the maleic anhydride-grafted polyolefin elastomer, the carbon black accounts for 1% of the mass of the maleic anhydride-grafted polyolefin elastomer, and the polyethylene glycol accounts for 6% of the mass of the maleic anhydride-grafted polyolefin elastomer.

[0008] The polyethylene glycol has a molecular weight of 700-1000; preferably, the polyethylene glycol is PEG800.

[0009] The ratio of the maleic anhydride-grafted polyolefin elastomer to the organic solvent in the whole system is 1g:18-20ml.

[0010] The amino content of the aminated multi-walled carbon nanotubes is 0.6-0.7 mmol / g, and their dimensions are: inner diameter of 3-5 nm, outer diameter of 8-15 nm, and length of 8-15 μm.

[0011] The nano-zinc oxide has a particle size of 15-20 nm.

[0012] The carbon black is superconducting carbon black.

[0013] The grade of the maleic anhydride-grafted polyolefin elastomer is N216.

[0014] In step (1), the mixture is stirred at 55-65℃ and 15-25 rpm for 3-4 hours. In step (2), the mixture is stirred at 800-1000 rpm for 1.5-2 hours to disperse it evenly; and stirred at 55-65℃ and 15-25 rpm for 1-2 hours.

[0015] The drying conditions in step (3) are: drying at 50-70℃ for 12-16 hours.

[0016] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows: (1) Highly efficient UV protection: The synergistic shielding system of ZnO + aminated multi-walled carbon nanotubes + carbon black achieves highly efficient blocking of ultraviolet light in the 250-400nm wavelength range. Performance data shows that when the ZnO addition amount is 1wt% (Example 2), the absorbance at 250nm reaches 0.442 and the absorbance at 400nm reaches 0.807, which is significantly better than the blank group (absorbance at 250nm 0.209 and absorbance at 400nm 0.228), effectively preventing the POE molecular chain from aging due to ultraviolet irradiation.

[0017] (2) Excellent and balanced mechanical properties: Based on the optimized ratio of POE-g-MAH + 1wt% ZnO + 6wt% PEG800, the mechanical degradation caused by the agglomeration of inorganic fillers is solved, and a balance between strength and toughness is achieved. Performance tests show that when the ZnO addition is 1wt%, the tensile strength of the composite film reaches 15.35MPa and the elongation at break reaches 929% (close to 956% of the blank group). Compared with the defects of traditional UV-resistant composite materials that "harden and become brittle" (such as the elongation at break of only 570% and tensile strength of 11.95MPa in Comparative Example 1), this system, while giving full play to the reinforcing effect of ZnO and aminated multi-walled carbon nanotubes, retains the flexibility of the POE-g-MAH matrix to the greatest extent, which can meet the mechanical performance requirements of flexible packaging and other scenarios.

[0018] (3) Good dispersion stability: Utilizing the synergistic effect of PEG800 and the MAH group in POE-g-MAH—the ether bond of PEG800 can form hydrogen bonds with the hydroxyl groups on the ZnO surface and the polar groups of POE-g-MAH, while the MAH group forms ester bonds with ZnO and amide bonds with aminated carbon nanotubes. This dual effect effectively inhibits the aggregation of inorganic particles. As shown in Examples 1-4, within the ZnO addition range of 0.5wt%-3wt%, no visible aggregation was observed in the composite film, and the mechanical and UV resistance data showed small fluctuations: the tensile strength was stable at 13.85-15.35 MPa, the absorbance at 250 nm was stable at 0.240-0.442, and the absorbance at 400 nm was stable at 0.614-0.807. The mechanical test repeatability was excellent, avoiding performance deviations caused by uneven dispersion.

[0019] (4) The anhydride groups (strongly polar) of POE-g-MAH can form stable chemical bonds with the inorganic components in the system: on the one hand, they undergo coordination reactions with the hydroxyl groups on the surface of ZnO to form ester bonds (COO); on the other hand, they undergo amidation reactions with the amino groups on the surface of aminated multi-walled carbon nanotubes to form amide bonds (C=O). This chemical bonding significantly enhances the interfacial bonding force between the inorganic filler and the POE-g-MAH matrix, avoiding the debonding of the particles and the matrix under stress, thereby ensuring mechanical properties. Compared with Comparative Example 3 (which uses multi-walled carbon nanotubes instead, without the formation of amide bonds), the tensile strength of this system increased by 43.8%, and the elongation at break increased by 82.8%, fully demonstrating the enhancing effect of interfacial chemical bonds on mechanical properties. Attached Figure Description

[0020] Figure 1 The UV-Vis absorption spectra of the composite films prepared in the blank group and Examples 1-4 of this invention are shown. Figure 2 The stress-strain curves of the composite films prepared in the blank group and Examples 1-4 of this invention are shown. Figure 3 Fourier transform infrared spectra of the composite films prepared in the blank group and Examples 1-4 of this invention; Figure 4 Fourier transform infrared spectra of the composite films prepared in the blank group and comparative examples 1, 2, 3, 5, and 6 of this invention; Figure 5 The stress-strain curves of the composite films prepared in the blank group and comparative examples 1, 2, 3, 5 and 6 of this invention are shown. Figure 6 The UV-Vis absorption spectra of the composite films prepared in the blank group and comparative examples 1, 2, 3, 5, and 6 of this invention are shown. Figure 7 From left to right, these are images of the composite films prepared in Examples 1, 2, and 3 of this invention. Figure 8 From left to right, the images show the appearance of the polyolefin film prepared in the blank group of this invention and the composite films prepared in Comparative Examples 1 and 3. Detailed Implementation

[0021] The technical solution of the present invention will be described in detail below with reference to specific embodiments and accompanying drawings, but the implementation of the present invention is not limited thereto.

[0022] The raw materials used in the embodiments and comparative examples of this invention are described below: The maleic anhydride-grafted polyolefin elastomer is manufactured by Dow Chemical Company of the United States. Its grade is N216, and the content of grafted maleic anhydride is 0.5%-1%. Tetrahydrofuran is reagent grade, with a tetrahydrofuran content of 99.0%. The nano zinc oxide was produced by Zhejiang Zhitai Nano Micro New Materials Co., Ltd., with the model number ZT-JH05. The zinc oxide content was 99%, the particle size was 15nm, and the specific surface area was 30-50㎡ / g. The nano-titanium dioxide was produced by Shanghai Maclean Biochemical Co., Ltd., with product number T818992, reagent grade, and a purity of 99.0%. Aminated multi-walled carbon nanotubes were manufactured by Shenzhen Suiheng Technology Co., Ltd., with product number SH-CNT-190. The purity was >99%, the amino content was 0.7 mmol / g, the inner diameter was 3-5 nm, the outer diameter was 8-15 nm, the length was 8-15 μm, and the specific surface area was 210 m² / g. The multi-walled carbon nanotubes were manufactured by Shenzhen Suiheng Technology Co., Ltd., with the product number SH-GS-103. The purity was >95%, the inner diameter was 3-5nm, the outer diameter was 8-15nm, the length was 3-12μm, and the specific surface area was 250㎡ / g. Polyethylene glycol (PEG800) was prepared by Shanghai Maclean Biochemical Co., Ltd., with product number P815607-500g, CAS number 25322-68-3, pH value 5.0-7.0, hydroxyl value 127-156mgKOH / g, and moisture content 1.0%. The carbon black was prepared by Fuzhou Yihuan Carbon Co., Ltd. It is a superconducting carbon black with a particle size of 40ml / 100g, an oil absorption of 290ml / 100g, a ash content of 0.01%, and a specific surface area of ​​62㎡ / g. Example 1: A method for preparing an anti-UV and antistatic polyolefin elastomer composite film, comprising the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.025g of nano-zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 0.5 wt%.

[0023] Example 2: A method for preparing an anti-UV and antistatic polyolefin elastomer composite film, comprising the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.05g of nano-zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 1 wt%.

[0024] Example 3: A method for preparing an anti-UV and antistatic polyolefin elastomer composite film, comprising the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.10g of nano-zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 2wt%.

[0025] Example 4: A method for preparing an anti-UV and antistatic polyolefin elastomer composite film, comprising the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.15g of nano-zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 3wt%.

[0026] Blank group A method for preparing a polyolefin elastomer film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive evaporation of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. The liquid in the flask was inverted onto a polytetrafluoroethylene plate and spread out. After cooling at room temperature for 30 minutes, it was dried in a forced-air drying oven at 60°C for 14 hours to obtain the polyolefin elastomer film.

[0027] Comparative Example 1 A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive evaporation of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.05g of nano-titanium dioxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a titanium dioxide content of 1 wt%.

[0028] Comparative Example 2 A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was then attached to the mouth of the flask, and argon gas was introduced. The other end of the flask was plugged with a stopper (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless and transparent liquid was obtained. 0.05g of nano-zinc oxide, 0.1g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and sonicated (250W, 30℃) for 1.5h, followed by magnetic stirring at 800rpm for 1.5h until uniformly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid in a three-necked flask and stirred at 25rpm for 1h at 60℃ to obtain a mixture. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. After cooling at room temperature for 30min, it was dried in a forced-air drying oven at 60℃ for 14h to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 1wt%.

[0029] Comparative Example 3 A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.05g of nano-zinc oxide, 0.05g of multi-walled carbon nanotubes, 0.05g of carbon black, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 1 wt%.

[0030] Comparative Example 4 A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was then attached to the mouth of the flask, and argon gas was introduced. The other end of the flask was plugged with a stopper (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless and transparent liquid was obtained. 0.05g of nano zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 2ml of KH550 and 10ml of tetrahydrofuran were added to a beaker and dispersed by magnetic stirring at 800rpm for 1.5h (particles were visible on the beaker wall). The dispersion was then added to the colorless and transparent liquid in the aforementioned three-necked flask and stirred at 60℃ and 25rpm. After stirring for a few minutes, obvious agglomeration occurred, and visible clumps and granules appeared in the system, making stirring difficult, forming lumps and preventing film formation.

[0031] Comparative Example 5 A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.05g of nano-zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 0.4g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 1 wt%.

[0032] Comparative Example 6 A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer particles and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was attached to the flask neck, argon gas was introduced, and the other end was plugged (to prevent excessive evaporation of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless, transparent liquid was obtained. 0.05g of nano-zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.3g of PEG800, and 10ml of tetrahydrofuran were added to a beaker and magnetically stirred at 800rpm for 1.5 hours until evenly dispersed. This mixture was then added to the aforementioned colorless, transparent liquid from the three-necked flask and stirred at 60°C and 25rpm for 1 hour to obtain a mixed solution. The mixture in the flask was inverted onto a polytetrafluoroethylene plate and spread out. It was cooled at room temperature for 30 minutes, and then dried in a forced-air drying oven at 60°C for 14 hours to obtain the UV-resistant and antistatic polyolefin elastomer composite film with a zinc oxide content of 1 wt%.

[0033] Comparative Example 7 A method for preparing an anti-UV and antistatic polyolefin elastomer composite film includes the following steps: Maleic anhydride-grafted polyolefin elastomer was dried in a 60°C oven for 12 hours. Then, 5g of transparent maleic anhydride-grafted polyolefin elastomer granules and 80ml of tetrahydrofuran were added to a 250ml three-necked flask. A condenser was then attached to the mouth of the flask, and argon gas was introduced. The other end of the flask was plugged with a stopper (to prevent excessive volatilization of tetrahydrofuran). The three-necked flask was then placed in a thermostatically heated magnetic stirrer and stirred at 60°C and 20rpm for 3.5 hours until a colorless and transparent liquid was obtained. 0.05g of nano zinc oxide, 0.05g of aminated multi-walled carbon nanotubes, 0.05g of carbon black, 8.2μL of KH550 (containing 0.035mmol of amino) and 10ml of tetrahydrofuran were added to a beaker and dispersed by magnetic stirring at 800rpm for 1.5h (particles were visible on the beaker wall). The dispersion was then added to the colorless and transparent liquid in the aforementioned three-necked flask and stirred at 60℃ and 25rpm. After stirring for a few minutes, obvious agglomeration occurred, and visible clumps and granular aggregates appeared in the system, making stirring difficult, forming lumps, and preventing film formation.

[0034] Characterization 1. Take pictures of the appearance of the composite films prepared in each embodiment and comparative example.

[0035] Figure 7 From left to right, these are images of the composite films prepared in Examples 1, 2, and 3 of this invention. Figure 8 From left to right, the images show the appearance of the polyolefin film prepared in the blank group of this invention and the composite films prepared in Comparative Examples 1 and 3.

[0036] from Figure 7 and Figure 8 It can be seen that: Figure 7 The composite films prepared in Examples 1 (0.5 wt%), 2 (1 wt%), and 3 (2 wt%) all exhibited a uniform black appearance, with smooth surfaces and no obvious agglomeration or delamination, indicating that the functional components within this dosage range were well dispersed in the matrix and had good system compatibility; while Figure 8 In the control group, the polyolefin film was clean and transparent white. Although the composite film of Comparative Example 1 was black, it had rough edges and irregular traces of component overflow, indicating poor dispersion uniformity. The composite film of Comparative Example 3 showed obvious phase separation and local agglomeration, with a mottled uneven structure on the surface, indicating poor compatibility between its components and poor dispersion effect.

[0037] 2. The composite films prepared in each embodiment and comparative example were characterized by Fourier transform infrared spectroscopy, such as... Figure 3 , Figure 4 As shown.

[0038] Compared to the control group, the structures, functional groups, and reaction details corresponding to the key wavenumbers in the examples are as follows: (1) 1650 cm -1 A new peak appears, corresponding to the characteristic absorption peak of the amide bond (C=O). This phenomenon indicates that the amino groups (-NH2) modified on the surface of the aminated multi-walled carbon nanotubes (CNT-NH2) underwent an amidation reaction with the carboxyl groups on the POE-g-MAH molecular chain, achieving chemical bonding between the two through the formation of stable amide covalent bonds. This chemical bonding significantly improves the dispersibility of carbon nanotubes in the POE matrix, avoids the decrease in conductivity caused by the aggregation of carbon nanotubes, and provides a structural basis for improving the antistatic properties of the composite film.

[0039] (2) 1250 cm -1 A new characteristic peak appeared at this position, corresponding to the absorption peak of the ester coordination bond (COO), while the blank group showed no obvious absorption signal at this position. This indicates that the carboxyl group in the POE-g-MAH molecule has undergone a coordination reaction with the hydroxyl group (-OH) on the surface of the ZnO nanoparticles, forming a stable ester coordination structure. This interfacial bonding enhances the compatibility between ZnO and the POE matrix, effectively inhibits the aggregation of ZnO particles in the system, and ensures their uniform dispersion in the matrix, thereby constructing a continuous and efficient UV shielding network and guaranteeing the UV resistance of the composite film.

[0040] (3) 1100 cm -1 A characteristic enhanced peak appears at 1250 cm⁻¹, corresponding to the absorption peak of the ether bond (CO). This ether bond originates from the dispersing solubilizer PEG800 added to the system. The ether bonds on its molecular chain can form hydrogen bonds with the polar groups on the surface of components such as POE-g-MAH and ZnO. This hydrogen bonding can further assist the uniform dispersion of inorganic particles such as ZnO in the matrix, and the absorption peak at 1250 cm⁻¹ is observed. -1 The dispersion effect of the ester coordination bonds is synergistic, which jointly optimizes the dispersion stability of the system, while avoiding the defect of easy migration of organic ultraviolet absorbers and improving the long-term performance of the composite film.

[0041] Performance testing The composite films prepared in each embodiment and comparative example were subjected to performance tests.

[0042] 1. Mechanical property testing: (1). Tensile strength / maximum force: The test was conducted at room temperature using a universal tensile testing machine. The test standard was based on GB / T1040.3-2006. The machine was equipped with a 5KN force sensor, a sampling frequency of 1000 / 5000Hz, and a deformation sensor YSJ50 / 25-ZC.

[0043] (2). Stress-strain curve: Based on the raw tensile test data obtained by the universal tensile test machine (GB / T 1040.3-2006 test standard), a standardized curve was plotted using Origin plotting software.

[0044] 2. Antistatic test: Tested in accordance with GB / T 31838.3-2019 "Dielectric and resistive properties of solid insulating materials - Part 3: Resistive properties (DC method) - Surface resistance and surface resistivity".

[0045] 3. UV protection test: Tested in accordance with GB / T 18830-2009 "Evaluation of UV protection performance of textiles".

[0046] The UV-Vis absorption spectra of the composite films prepared in Examples 1-4 are shown below. Figure 1 The UV-Vis absorption spectra of the composite films prepared in Comparative Examples 1, 2, 3, 5, and 6 are shown in the figure. Figure 6 The stress-strain curves of the composite films prepared in Examples 1-4 are shown below. Figure 2 The stress-strain curves of the composite films prepared in Comparative Examples 1, 2, 3, 5, and 6 are shown in the figure. Figure 5 .

[0047] The performance test results of the composite films prepared in each embodiment and comparative example are shown in Table 1 below.

[0048] Table 1 As can be seen from Table 1: The performance data from Examples 1-4 clearly show that Example 2, with 1 wt% ZnO, is the optimal formulation. While maintaining the high mechanical properties of the matrix (elongation at break 929%, close to the 956% of the blank group), it also achieves longitudinal tensile strength (15.35 MPa), UV resistance (absorbance at 250 nm 0.442, absorbance at 400 nm 0.807), and antistatic properties (surface resistivity 10 Ω·cm). 9 The overall optimal value of ZnO (Ω·cm) is achieved. When the ZnO addition is less than 1 wt% (Example 1, 0.5 wt%), the UV shielding ability is insufficient (the absorbance is significantly lower than that of Example 2). However, when the ZnO addition exceeds 1 wt% (Examples 3-4, 2 wt% and 3 wt%), the elongation at break decreases significantly due to slight agglomeration of the filler (as low as 576%), but the UV resistance and antistatic properties remain at a relatively good level.

[0049] Compared with Example 2, Comparative Example 1 used TiO2 (0.05g) instead of ZnO (0.05g) in Example 2, while keeping the other formulation components the same. The absorbance at 250nm decreased from 0.442 to 0.266, and at 400nm from 0.807 to 0.644, indicating that TiO2's ultraviolet absorption capacity in both the UVB (250nm) and UVA (400nm) bands was weaker than that of ZnO in this system. However, the mechanical properties deteriorated significantly, with the elongation at break decreasing from 929% to 570%, and the longitudinal tensile strength decreasing from 15.35MPa to 11.95MPa. The antistatic properties also weakened, with the surface resistivity decreasing from 10... 9 Ω.cm increased to 10 10 Ω.cm. ZnO is a superior UV absorber in this system, possessing not only stronger full-band UV shielding capability but also better interfacial compatibility with the POE-g-MAH matrix; TiO2's UV absorption efficiency and interfacial compatibility are inferior to ZnO. The interfacial compatibility between TiO2 and the POE-g-MAH matrix is ​​significantly weaker than that of ZnO. The poor match between the surface polarity of TiO2 and the weak polarity of the matrix leads to easy interfacial debonding of particles and the matrix under stress, resulting in ineffective stress transfer and ultimately a significant deterioration in the material's toughness and strength.

[0050] Compared to Example 2, Comparative Example 2 increased the amount of aminated multi-walled carbon nanotubes from 0.05 g to 0.1 g, while keeping the other components unchanged. The absorbance at 250 nm decreased from 0.442 to 0.271, and the absorbance at 400 nm decreased from 0.807 to 0.707, indicating that excessive aminated multi-walled carbon nanotubes interfered with the UV absorption effect of ZnO; the surface resistivity remained at 10 Ω·cm. 9 The antistatic range is Ω.cm; however, the mechanical properties decrease significantly, with elongation at break dropping from 929% to 587%, and longitudinal tensile strength decreasing from 15.35 MPa to 11.55 MPa. The optimal addition amount of aminated multi-walled carbon nanotubes is 0.05 g. Excessive addition (0.1 g) will cause carbon nanotube aggregation, destroying the toughness of the matrix and making it prone to cracking under stress. At the same time, the rigidity of excessive carbon nanotubes also limits the deformation ability of the matrix chain segments, ultimately leading to a double decrease in toughness and strength, while weakening the ultraviolet shielding ability of ZnO without any additional performance gain.

[0051] Compared to Example 2, Comparative Example 3 replaced the aminated multi-walled carbon nanotubes (0.05 g) in Example 2 with multi-walled carbon nanotubes (0.05 g), while the other formulation components remained unchanged. The mechanical properties deteriorated significantly, with the elongation at break decreasing from 929% to 508% and the longitudinal tensile strength decreasing from 15.35 MPa to 10.67 MPa; the antistatic properties also weakened significantly, with the surface resistivity decreasing from 10... 9 Ω.cm increased to 10 10The absorbance at 250 nm decreased from 0.442 to 0.267, and at 400 nm from 0.807 to 0.681. This result indicates that the amination modification of aminated multi-walled carbon nanotubes is key to improving performance—the amino group can form amide bonds with the MAH group of POE-g-MAH, enhancing interfacial bonding and dispersibility, while also improving the synergistic effect with ZnO in the ultraviolet light. The weak interfacial bonding and poor dispersibility of multi-walled carbon nanotubes lead to a significant decrease in performance.

[0052] Compared to Example 2, Comparative Example 5 increased the amount of PEG800 from 0.3g to 0.4g, while keeping the other formulation components unchanged. The absorbance at 250nm decreased from 0.442 to 0.218, and the absorbance at 400nm decreased from 0.807 to 0.619, indicating that excessive PEG800 may have encapsulated ZnO, weakening its UV absorption capacity. Mechanical properties deteriorated significantly, with elongation at break decreasing from 929% to 527%, and longitudinal tensile strength decreasing from 15.35MPa to 9.55MPa. Antistatic properties were also weaker, with surface resistivity decreasing from 10... 9 Ω.cm increased to 10 11 Ω.cm. The optimal addition amount of PEG800 is 0.3g. Excessive addition will weaken the entanglement of POE-g-MAH molecular chains, resulting in a decrease in the mechanical properties and antistatic properties of the matrix, while also interfering with the UV absorption efficiency of ZnO.

[0053] Compared with Example 2, Comparative Example 6 removed carbon black (0.05 g) from Example 2, while keeping the other formulation components unchanged. The absorbance at 250 nm decreased from 0.442 to 0.243, and the absorbance at 400 nm decreased from 0.807 to 0.658, indicating that carbon black can synergistically enhance the UV shielding effect with ZnO and aminated multi-walled carbon nanotubes; mechanical properties decreased, with elongation at break decreasing from 929% to 565%, and longitudinal tensile strength decreasing from 15.35 MPa to 14.20 MPa; antistatic properties weakened, with surface resistivity decreasing from 10... 9 Ω.cm increased to 10 10 Ω.cm. Carbon black, as a rigid reinforcing filler, can form physical entanglement with the matrix, improving the toughness and strength of the material; after removing carbon black, the matrix loses the supporting effect of the rigid filler, the resistance to chain segment deformation decreases, the toughness drops significantly, and the strength is slightly reduced due to the lack of synergistic reinforcement from the rigid filler.

[0054] Compared to Example 2, Comparative Example 4 replaced PEG800 (0.3g) in Example 2 with KH550 (2ml), while the other formulation components remained unchanged. In the system, KH550 initiated self-condensation and excessive crosslinking. The amino group of KH550 underwent an amidation reaction with the maleic anhydride group of POE-g-MAH, forming interfacial covalent bonds, resulting in high aggregation in the three-necked flask and failure to form a film.

[0055] Compared to Example 2, Comparative Example 7 replaced PEG800 (0.3 g) in Example 2 with KH550 (8.2 μL), while the other formulation components remained unchanged. Even a very low concentration of KH550 in the system still triggered self-condensation and excessive crosslinking. The amino groups of KH550 underwent an amidation reaction with the maleic anhydride groups of POE-g-MAH, forming interfacial covalent bonds, resulting in high agglomeration in the three-necked flask and failure to form a film.

[0056] The composite film prepared by this invention can be specifically applied to flexible packaging films for electronic components, and to the transportation and storage of precision electronic components. Its surface resistivity reaches 10⁻⁶. 9 With an absorbance of Ω·cm, it effectively eliminates static electricity accumulation, preventing electrostatic discharge from damaging sensitive electronic components and preventing dust from adsorbing and contaminating the component surface; its high UV resistance, with an absorbance of 0.442 at 250nm and 0.807 at 400nm, can block external ultraviolet rays from aging the packaging film and prevent the film from becoming brittle and losing protection for the components; its high elongation at break of 929% gives it excellent flexibility, allowing it to fit tightly to components of different sizes; and its tensile strength of 15.35MPa can withstand slight compression and pulling during packaging and transportation.

[0057] The above description, in conjunction with specific embodiments, provides a further detailed explanation of the present invention. It should not be construed that the specific embodiments of the present invention are limited to these descriptions. For those skilled in the art, various substitutions or modifications can be made to these described embodiments without departing from the concept of the present invention, and all such substitutions or modifications should be considered within the scope of protection of the present invention.

Claims

1. A method for preparing an anti-UV and antistatic polyolefin elastomer composite film, characterized in that, Includes the following steps: (1) Dissolve maleic anhydride-grafted polyolefin elastomer in 80%-90% of the total organic solvent and stir until it becomes a colorless and transparent liquid. (2) Mix nano zinc oxide, aminated multi-walled carbon nanotubes, carbon black, polyethylene glycol and the remaining organic solvent, disperse evenly and then add to the colorless and transparent liquid obtained in (1), stir to obtain a mixture; (3) The mixture obtained in (2) is inverted onto a flat plate and spread out. After cooling and solidification at room temperature, it is dried to obtain the UV-resistant and antistatic polyolefin elastomer composite film.

2. The preparation method according to claim 1, characterized in that, The organic solvent in steps (1) and (2) is tetrahydrofuran.

3. The preparation method according to claim 1, characterized in that, The nano zinc oxide, aminated multi-walled carbon nanotubes, carbon black, and polyethylene glycol account for 1%, 1%, 1%, and 6% of the mass of the maleic anhydride-grafted polyolefin elastomer, respectively.

4. The preparation method according to claim 1, characterized in that, The molecular weight of the polyethylene glycol is 700-1000.

5. The preparation method according to claim 4, characterized in that, The polyethylene glycol is PEG800.

6. The preparation method according to claim 2, characterized in that, The ratio of the maleic anhydride-grafted polyolefin elastomer to the organic solvent in the whole system is 1g:18-20ml.

7. The preparation method according to claim 1, characterized in that, The amino content of the aminated multi-walled carbon nanotubes is 0.6-0.7 mmol / g, and their dimensions are: inner diameter of 3-5 nm, outer diameter of 8-15 nm, and length of 8-15 μm.

8. The preparation method according to claim 1, characterized in that, The nano zinc oxide has a particle size of 15-20 nm; and / or the carbon black is superconducting carbon black; and / or the maleic anhydride-grafted polyolefin elastomer is grade N216.

9. The preparation method according to claim 1, characterized in that, In step (1), the mixture is stirred at 55-65℃ and 15-25 rpm for 3-4 hours; and / or In step (2), the mixture is stirred at 800-1000 rpm for 1.5-2 hours to disperse it evenly; and stirred at 55-65℃ and 15-25 rpm for 1-2 hours.

10. The preparation method according to claim 1, characterized in that, The drying conditions in step (3) are: drying at 50-70℃ for 12-16 hours.

Images