Environment-friendly mildew-proof hydrophobic EVA composition and preparation method thereof

Abstract

This invention discloses an environmentally friendly, mildew-resistant, and hydrophobic EVA composition and its preparation method, belonging to the field of plastics technology. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition provided by this invention comprises the following components: 80-100 parts of ethylene-vinyl acetate copolymer, 3-8 parts of compatibilizer, 10-20 parts of heat-resistant hydrophobic modified masterbatch, 10-30 parts of mica powder, 2-10 parts of antibacterial and mildew-resistant masterbatch, 0.1-2 parts of lubricant, and 0.1-1 parts of antioxidant. The heat-resistant hydrophobic modified masterbatch is polysiloxane-grafted EVA with fluorinated side chains and cyclic hard segments. The EVA composition provided by this invention has good tensile strength, hydrophobic effect, antibacterial and mildew-resistant properties, and heat resistance, making it suitable for use as a material in applications such as shower curtains that operate under high temperature and high humidity conditions for extended periods.

Description

Technical Field

[0001] This invention relates to the field of plastics technology, specifically to an environmentally friendly, mildew-resistant, and hydrophobic EVA composition and its preparation method. Background Technology

[0002] EVA (ethylene-vinyl acetate copolymer) is a polymer material formed by the high-pressure polymerization of ethylene and vinyl acetate. It possesses excellent elasticity and flexibility, along with superior optical and mechanical properties and good processability, making it widely used in adhesives, sports protective gear, automotive interiors, electrical insulation materials, packaging materials, and functional composite materials. EVA films are odorless, waterproof, corrosion-resistant, soft, and have good drape, making them more suitable for use as shower curtains in home environments compared to traditional fabrics and PVC. However, plastic materials are prone to attracting bacteria or mold in high-temperature and humid environments, leading to discoloration, degradation, and odors, and also reducing the strength of EVA films. Therefore, there is still a need to develop an environmentally friendly, mildew-resistant, and hydrophobic EVA composition. Summary of the Invention

[0003] To overcome the shortcomings of the existing technology, the present invention provides an environmentally friendly anti-mildew and hydrophobic EVA composition and its preparation method.

[0004] The technical solution for achieving the objective of this invention is as follows:

[0005] An environmentally friendly anti-mildew and hydrophobic EVA composition, by weight, comprises the following components: 80-100 parts of ethylene-vinyl acetate copolymer, 3-8 parts of compatibilizer, 10-20 parts of heat-resistant and hydrophobic modified masterbatch, 10-30 parts of mica powder, 2-10 parts of antibacterial and anti-mildew masterbatch, 0.1-2 parts of lubricant, and 0.1-1 parts of antioxidant. The heat-resistant and hydrophobic modified masterbatch is polysiloxane-grafted EVA with fluorinated side chains and cyclic hard segments.

[0006] In one specific embodiment, the preparation method of the heat-resistant hydrophobic modified masterbatch includes the following steps:

[0007] S1. Octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane and trimethylsilanol are mixed and subjected to anionic ring-opening polymerization in a hexane solution containing n-butyllithium, with N-Boc-3-chlorodimethylsilylpropylamine as the end-capping agent, to obtain a polysiloxane with Boc-amino end-capping and Si-H side chain.

[0008] S2. A Karstedt catalyst was added to a Boc-amino-terminated polysiloxane solution with Si-H side chains. 2-Perfluorohexylethyl methacrylate and isobornyl methacrylate were added to the Boc-amino-terminated polysiloxane solution with Si-H side chains for hydrosilylation. The amino protection was removed with a trifluoroacetic acid / dichloromethane solution to obtain a monoamino-terminated polysiloxane with fluorinated side chains and cyclic hard segments.

[0009] S3. Maleic anhydride-grafted EVA, antioxidant and catalyst are put into a mixer and mixed evenly. Then, polysiloxane with monoamino end caps, fluorine-containing side chains and cyclic hard segments is added and mixed evenly. After removing the hot melt, it is cooled and crushed to obtain polysiloxane-grafted EVA with fluorine-containing side chains and cyclic hard segments, which is the heat-resistant hydrophobic modified masterbatch.

[0010] In one specific embodiment, the molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, trimethylsilanol and N-Boc-3-chlorodimethylsilylpropylamine is (0.7~0.9):(0.1~0.3):(0.55~2.1):(0.5~2.0). Preferably, the molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, trimethylsilanol and N-Boc-3-chlorodimethylsilylpropylamine is (0.7~0.9):(0.1~0.3):(1.05~2.1):(1.05~2.0).

[0011] In one specific embodiment, N-Boc-3-chlorodimethylsilylpropylamine is a compound with the following structure:

[0012] .

[0013] In one specific embodiment, the molecular weight of the Boc-amino-terminated, Si-H-containing polysiloxane is 3000~15000 g / mol.

[0014] In one specific embodiment, the molar ratio of 2-perfluorohexylethyl methacrylate to isobornyl methacrylate is (6~8):(2~4).

[0015] In one specific embodiment, the grafting rate of maleic anhydride in the maleic anhydride-grafted EVA is 0.8~1.5wt%, and the mass ratio of the maleic anhydride-grafted EVA to the monoamino-terminated, fluorinated side-chain polysiloxane with cyclic hard segments is 100:(12~150).

[0016] In one specific embodiment, the vinyl acetate content of the ethylene-vinyl acetate copolymer is 6~15wt%, and the melt index is 1.8~25g / 10min at 190℃ and 2.16kg.

[0017] In one specific embodiment, the compatibilizer is maleic anhydride-grafted EVA; the lubricant is at least one of zinc stearate, calcium stearate, and stearic acid; the antioxidant is at least one of antioxidant 1010 and antioxidant 168; the antibacterial and antifungal masterbatch is a compound of inorganic zinc-based antibacterial agent and organic antifungal agent, and the carrier is EVA.

[0018] In one specific embodiment, the mica powder is surface modified with an aminosilane coupling agent, wherein the amount of the aminosilane coupling agent added is 1-3 wt% of the mica powder.

[0019] This invention also protects the preparation method of the environmentally friendly anti-mildew and hydrophobic EVA composition, comprising the following steps: mixing ethylene-vinyl acetate copolymer, compatibilizer, heat-resistant hydrophobic modified masterbatch, mica powder, antibacterial and anti-mildew masterbatch, lubricant, and antioxidant in proportion and stirring to obtain a semi-gelled mixture; shearing and kneading the semi-gelled mixture to obtain granules; filtering the obtained granules; and obtaining the environmentally friendly anti-mildew and hydrophobic EVA composition.

[0020] Preferably, the stirring speed is 500-1000 rpm and the stirring temperature is 85-105℃.

[0021] Preferably, the filtration is performed using a filter press, which uses an 80-200 mesh filter screen to filter the colloidal particles, and the screw speed of the filter press is controlled below 60 rpm.

[0022] Beneficial effects

[0023] This invention provides an environmentally friendly, mildew-resistant, and hydrophobic EVA composition and its preparation method. Modified polysiloxane and maleic anhydride-grafted EVA are linked via amide bond reactions, solving the problem of phase separation that easily occurs when directly blending polysiloxane and EVA through chemical crosslinking. Simultaneously, fluorinated segments and cyclic hard segments are grafted onto the side chains of the polysiloxane, reducing the surface energy of the EVA material and improving its hydrophobicity and heat resistance, making it suitable for long-term use in high-temperature and high-humidity environments. Furthermore, the addition of mica powder, surface-treated with an aminosilane coupling agent, not only imparts a pearlescent effect to the inherently transparent EVA material, meeting aesthetic requirements, but also reacts and crosslinks with the maleic anhydride groups on the maleic anhydride-grafted EVA and any unconsumed maleic anhydride groups in the heat-resistant hydrophobic masterbatch, thereby improving the material's mechanical properties. Attached Figure Description

[0024] Figure 1 A schematic diagram of the synthetic route for polysiloxane-grafted EVA with fluorinated side chains and cyclic hard segments;

[0025] Figure 2 The 1H NMR spectrum of N-Boc-3-chlorodimethylsilylpropylamine;

[0026] Figure 3 Infrared spectra of Boc-amino-terminated polysiloxanes with Si-H side chains, monoamino-terminated polysiloxanes with fluorine-containing side chains and cyclic hard segments, and heat-resistant hydrophobic modified masterbatch 1. Detailed Implementation

[0027] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] Unless otherwise specified, the experimental methods used in the embodiments are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0029] The raw materials used in the examples and comparative examples are described below:

[0030] Ethylene-vinyl acetate copolymer: vinyl acetate content 9wt%, melt index 2g / 10min at 190℃ and 2.16kg; grade 155, Yanshan Petrochemical;

[0031] Maleic anhydride-grafted EVA: ST-3, grafting rate: 1.0-1.4wt%, melt index (190℃, 2.16kg): 0.8-1.5g / 10min, Nanjing Sutai;

[0032] Antibacterial and antifungal masterbatch: Inorganic zinc-based antibacterial agent and organic antifungal agent, EVA as carrier, HY-FM03, Shenzhen Hengyang Nanomaterials Co., Ltd.;

[0033] Mica powder: Synthetic mica powder, 600 mesh, China Crystal New Materials Holding Co., Ltd.; prepared by wet surface modification using 1.2% aminosilane coupling agent (KH-550). The specific preparation steps are as follows: mica powder is dried at 110℃ for 60 min. Pre-hydrolyzed solution is prepared by mixing 240 ml of anhydrous ethanol and 60 ml of deionized water, adding glacial acetic acid to adjust the pH to 3.5-4, adding 120 g of aminosilane coupling agent KH-550, stirring in a 60℃ water bath for 10 min until clear, adding 10 kg of hot mica powder to a high-speed mixer, setting the temperature to 60℃ and the speed to 300 rpm, and uniformly spraying the pre-hydrolyzed solution into the mixer within 3-5 min using a peristaltic pump, continuing to stir for 15 min, and drying the material at 80℃ for 30 min after discharge, and passing it through a 100-mesh sieve to obtain surface-treated mica powder.

[0034] Lubricant: Calcium stearate, commercially available;

[0035] Antioxidant: A mixture of antioxidant 1010 and antioxidant 168 in a 1:1 mass ratio, commercially available;

[0036] Amino-capping agent: Under a nitrogen atmosphere, 1 mol of allylamine and 1.1 mol of triethylamine were dissolved in tetrahydrofuran to prepare a solution with a total concentration of 1 mol / L. 1.05 mol of di-tert-butyl dicarbonate was dissolved in tetrahydrofuran solution to prepare a solution with a concentration of 1 mol / L. The di-tert-butyl dicarbonate solution was added dropwise to the allylamine solution under ice bath conditions and stirred evenly. The ice bath was removed and stirring was continued at room temperature for 3 hours. The solution was washed successively with deionized water and saturated sodium bicarbonate solution, and dried by rotary evaporation at 35°C to obtain N-Boc-allylamine with a yield of 90.2%.

[0037] Under anhydrous and light-protected conditions, 1 mol of N-Boc-allylamine was dissolved in tetrahydrofuran to prepare a 1 mol / L solution. 1 mol of dimethylchlorosilane was also dissolved in tetrahydrofuran to prepare a 1 mol / L solution. A solution of isopropanol chloroplatinate containing 10 ppm Pt was added to the N-Boc-allylamine solution. Under ice bath conditions, the dimethylchlorosilane solution was added dropwise to the N-Boc-allylamine solution over 30 min. After stirring for 5 min, the temperature was raised to 35 °C and reacted for 2 hours in the dark. ¹H NMR confirmed the disappearance of δ4.7 (Si-H). The reaction was stopped, platinum was removed by filtration, and the solvent was removed by rotary evaporation under reduced pressure at 30 °C to obtain N-Boc-3-chlorodimethylsilylpropylamine, with a yield of 82.3%. ¹H NMR confirmed its structure, as shown below. Figure 2 As shown.

[0038] Heat-resistant and hydrophobic modified masterbatch 1: Self-made, preparation method is as follows:

[0039] S1. Pre-dry the reaction vessel and raw materials to remove moisture and purge with nitrogen to ensure the reaction system is anhydrous and oxygen-free. Under a nitrogen atmosphere, add 1.05 mol trimethylsilanol, 0.85 mol octamethylcyclotetrasiloxane, 0.15 mol tetramethylcyclotetrasiloxane, and 300 ml anhydrous tetrahydrofuran to the reaction vessel. Cool to -10°C. Using a syringe, slowly add 170 ml of a 2.5 mol / L n-butyllithium ethane solution dropwise to the reaction system, completing the addition within 15 minutes. Maintain the temperature at -10°C and stir for 30 minutes. Allow the temperature to rise naturally to 25°C and continue stirring for 3 hours. Cool down to 0°C again. Using a syringe, add 1 mol N-Boc-3-chlorodimethylsilylpropylamine (diluted with 200 ml tetrahydrofuran) dropwise, stirring for 30 minutes. Add 5 mL of deionized water to the syringe to quench the reaction, stirring for 5 minutes. After min, the organic layer was separated and washed once with 100 ml of saturated sodium bicarbonate solution and once with 100 ml of saturated sodium chloride solution. It was then dried with anhydrous magnesium sulfate. The residual monomer and solvent were removed by pumping oil at 0.5 mbar and 30 °C for 2 hours to obtain a Boc-amino-terminated polysiloxane with Si-H side chains. The molecular weight was determined to be 5800 g / mol by GPC.

[0040] S2. Dissolve 0.4 mol of 2-perfluorohexylethyl methacrylate, 0.2 mol of isobornyl methacrylate, and 0.05 wt% of 2,6-di-tert-butyl-p-cresol as a polymerization inhibitor in 100 ml of anhydrous toluene. Deoxygenate by bubbling under nitrogen for 10 min. Dissolve the Boc-amino-terminated polysiloxane with Si-H side chains obtained in S1 in 200 ml of anhydrous toluene. Deoxygenate by bubbling under nitrogen for 10 min. Protect from light. Add a Karstedt catalyst containing 10 ppm Pt (prepared as a 0.5% toluene solution) to the Boc-amino-terminated polysiloxane solution. Stir at room temperature for 5 minutes. The mixture of 2-perfluorohexylethyl methacrylate and isobornyl methacrylate monomers was pre-cooled at 0°C and slowly added dropwise to a polysiloxane solution with Boc-amino-terminated and Si-H side chains over 2 hours. After the addition was complete, the temperature was raised to 35°C and stirred for 1 hour. 5 ml of a 0.5 wt% triphenylphosphine toluene solution was added to quench the reaction. The organic phase was washed once with 50 ml of saturated sodium bicarbonate and once with 50 ml of saturated sodium chloride, and dried over anhydrous magnesium sulfate. The organic phase was cooled to 0°C, and 50 mL of trifluoroacetic acid / dichloromethane (1:1, v / v) was added dropwise. The mixture was stirred at room temperature for 10 min to remove the amino protection. The trifluoroacetic acid and solvent were removed by rotary evaporation at 30°C. The residual monomer and solvent were removed by pumping oil at 0.5 mbar and stirring at 30°C for 2 hours to obtain a monoamino-terminated polysiloxane with fluorinated side chains and cyclic hard segments.

[0041] S3. Add 100 parts of maleic anhydride-grafted EVA, 0.5 parts of antioxidant 1010, 0.2 parts of antioxidant BHT and 0.1 parts of catalyst dibutyltin disilicate into a mixer. Set the temperature to 150℃ and the speed to 50 rpm. Melt for 2 minutes. Add 40 parts of monoamino-terminated, fluorine-containing side-chain and cyclic hard-segment polysiloxane at once and continue mixing for 3 minutes. Remove the hot melt, cool and crush to obtain polysiloxane-grafted EVA with fluorine-containing side-chain and cyclic hard-segment, which is the heat-resistant hydrophobic modified masterbatch 1.

[0042] Among them, the infrared spectra of Boc-amino-terminated polysiloxanes, polysiloxanes with Si-H side chains, monoamino-terminated polysiloxanes with fluorine-containing side chains and cyclic hard segments, and heat-resistant hydrophobic modified masterbatch 1 are as follows: Figure 3 As shown, from Figure 3 As can be seen, infrared absorption peaks of the -NH group and C=O group of the Boc-amino-terminated polysiloxane and the Si-H group of the side chain were detected in the polysiloxane, indicating the successful preparation of the polysiloxane with Boc-amino-terminated and Si-H side chain. In the polysiloxane with monoamino-terminated, fluorine-containing side chain and cyclic hard segments, the infrared absorption peak of -NH2 was detected, while the Si-H peak disappeared, proving the successful preparation of the polysiloxane with monoamino-terminated, fluorine-containing side chain and cyclic hard segments. In the heat-resistant hydrophobic modified masterbatch, i.e., polysiloxane grafted with EVA containing fluorine-containing side chain and cyclic hard segments, infrared characteristic peaks of Si-O-Si and Si-C in the siloxane segments were detected, indicating the successful preparation of heat-resistant hydrophobic modified masterbatch 1.

[0043] Heat-resistant and hydrophobic modified masterbatch 2: Compared with heat-resistant and hydrophobic modified masterbatch 1, the difference is that the amount of octamethylcyclotetrasiloxane added in step S1 is modified to 0.7 mol, the amount of tetramethylcyclotetrasiloxane added is modified to 0.3 mol, and the molecular weight of the polysiloxane with Boc-amino end cap and Si-H side chain is 6200 g / mol as determined by GPC.

[0044] Heat-resistant and hydrophobic modified masterbatch 3: Compared with heat-resistant and hydrophobic modified masterbatch 1, the difference is that the amount of octamethylcyclotetrasiloxane added in step S1 is modified to 0.9 mol, the amount of tetramethylcyclotetrasiloxane added is modified to 0.1 mol, and the molecular weight of the polysiloxane with Boc-amino end cap and Si-H side chain is 5400 g / mol as detected by GPC.

[0045] Heat-resistant and hydrophobic modified masterbatch 4: Compared with heat-resistant and hydrophobic modified masterbatch 1, the difference is that the amount of trimethylsilanol added in step S1 is modified to 2.1 mol, the amount of N-Boc-3-chlorodimethylsilylpropylamine added is modified to 2 mol, and the molecular weight of the polysiloxane with Boc-amino end caps and Si-H side chains detected by GPC is 3000 g / mol.

[0046] Heat-resistant and hydrophobic modified masterbatch 5: Compared with heat-resistant and hydrophobic modified masterbatch 1, the difference is that the amount of 2-perfluorohexylethyl methacrylate added in step S2 is modified to 0.48 mol, and the amount of isobornyl methacrylate added is modified to 0.12 mol.

[0047] Heat-resistant and hydrophobic modified masterbatch 6: Compared with heat-resistant and hydrophobic modified masterbatch 1, the difference is that the amount of 2-perfluorohexylethyl methacrylate added in step S2 is modified to 0.6 mol, and isobornyl methacrylate is not added.

[0048] Heat-resistant and hydrophobic modified masterbatch 7: Compared with heat-resistant and hydrophobic modified masterbatch 1, the difference is that 2-perfluorohexylethyl methacrylate is not added in step S2, and the amount of isobornyl methacrylate added is modified to 0.6 mol.

[0049] Heat-resistant hydrophobic modified masterbatch 8: Compared with heat-resistant hydrophobic modified masterbatch 1, the difference is that in step S1, the end-capping agent N-Boc-3-chlorodimethylsilylpropylamine is replaced with trimethylchlorosilane, and obvious phase separation occurs in the masterbatch.

[0050] Unless otherwise specified, all components and raw materials used in the embodiments and comparative examples of this invention are commercially available, and the same type of components and raw materials are used in each parallel experiment.

[0051] Examples and Comparative Examples

[0052] An environmentally friendly, mildew-resistant, and hydrophobic EVA composition is prepared by the following steps: ethylene-vinyl acetate copolymer, compatibilizer, heat-resistant hydrophobic modified masterbatch, mica powder, antibacterial and mildew-resistant masterbatch, lubricant, and antioxidant are mixed and stirred in proportion to obtain a semi-gelatinized mixture; the semi-gelatinized mixture is sheared and kneaded to obtain granules; the obtained granules are filtered to obtain the environmentally friendly, mildew-resistant, and hydrophobic EVA composition. The stirring speed is 800 rpm and the stirring temperature is 105℃. Filtration is performed using a filter press with a 100-mesh filter screen to filter the granules, and the screw speed of the filter press is controlled at 40 rpm. The specific components and proportions of the antibacterial and mildew-resistant EVA composition are shown in Table 1.

[0053] Table 1. Specific components and proportions of the environmentally friendly, mildew-resistant, and hydrophobic EVA composition.

[0054]

[0055] Environmentally friendly, mildew-resistant, and hydrophobic EVA granules were cast using a casting machine. The granules were pushed onto the die head of the casting machine for extrusion molding. The temperature difference between the die head and the cooling roller was not less than 40°C. A sheet with a thickness of 0.15 mm was obtained. The resulting sheet underwent the following performance tests, and the results are shown in Table 2.

[0056] (1) Tensile strength: The tensile properties of the sheet were tested according to ISO 527-2012 "Determination of tensile properties of plastics", at 23℃ and a tensile rate of 50 mm / min.

[0057] (2) Surface energy: The surface energy of the sheet was tested according to GB / T 30693-2014 standard;

[0058] (3) Hydrophobic properties: The hydrophobic effect of the sheet is evaluated by measuring the water contact angle of the sheet in the air. The larger the contact angle, the less likely the sheet surface is to be wetted, and the better the hydrophobic effect.

[0059] (4) Antibacterial rate: The antibacterial rate was tested and calculated at 28℃ according to Appendix A of QB / T2591-2003. The formula for calculating the antibacterial rate is: R(%=(BC) / B×100, where: R-antibacterial rate (%), B-average number of recovered bacteria in blank control sample (cfu / tablet), C-average number of recovered bacteria in antibacterial plastic sample (cf / tablet); test bacteria: Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538P;

[0060] (5) Anti-mold grade: Refer to Appendix B of QB / T2591-2003 for testing and rating under 28℃ conditions. The mold growth grades of the samples are as follows: Grade 0 - no growth, that is, no growth is observed under a microscope (50x magnification); Grade 1 - trace growth, that is, growth is visible to the naked eye, but the growth coverage area is less than 10%; Grade 2 - growth coverage area is not less than 10%. The molds used for testing are: Trichoderma viride ATCC 9645, Aspergillus brasiliensis ATCC 9642, Chaetomium globosum ATCC 6205, and Brachyderma buddingis ATCC 15233.

[0061] (6) Heat aging resistance: The sheet was placed in a humid heat aging chamber at 85℃ and 85%RH for 1000 h. After taking it out, the retention rate of its tensile strength relative to the tensile strength before aging was tested.

[0062] Table 2 Performance test results of environmentally friendly anti-mildew and hydrophobic EVA compositions

[0063]

[0064] As can be seen from the data in the examples and comparative examples, the EVA composition provided by the present invention has good tensile strength, hydrophobicity, antibacterial and antifungal properties and heat resistance, which meets the application requirements of materials in high temperature and high humidity environments such as shower curtains.

[0065] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An environmentally friendly, mildew-resistant, and hydrophobic EVA composition, characterized in that, The product comprises the following components by weight: 80-100 parts of ethylene-vinyl acetate copolymer, 3-8 parts of compatibilizer, 10-20 parts of heat-resistant and hydrophobic modified masterbatch, 10-30 parts of mica powder, 2-10 parts of antibacterial and antifungal masterbatch, 0.1-2 parts of lubricant, and 0.1-1 parts of antioxidant. The heat-resistant and hydrophobic modified masterbatch is polysiloxane-grafted EVA with fluorine-containing side chains and cyclic hard segments. The preparation method of the heat-resistant hydrophobic modified masterbatch includes the following steps: S1. Octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, and trimethylsilanol are mixed and subjected to anionic ring-opening polymerization in a hexane solution containing n-butyllithium, using N-Boc-3-chlorodimethylsilylpropylamine as a capping agent to obtain a Boc-amino-terminated polysiloxane with Si-H side chains. The molar ratio of octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane, trimethylsilanol, and N-Boc-3-chlorodimethylsilylpropylamine is (0.7~0.9):(0.1~0.3):(0.55~2.1):(0.5~2.0). S2. A Karstedt catalyst is added to a Boc-amino-terminated polysiloxane solution containing Si-H side chains. 2-Perfluorohexylethyl methacrylate and isobornyl methacrylate are added to the Boc-amino-terminated polysiloxane solution containing Si-H side chains for hydrosilylation. The amino protection is removed with a trifluoroacetic acid / dichloromethane solution to obtain a monoamino-terminated polysiloxane with fluorinated side chains and cyclic hard segments. The molar ratio of 2-perfluorohexylethyl methacrylate to isobornyl methacrylate is (6~8):(2~4). S3. Maleic anhydride-grafted EVA, antioxidant, and catalyst are added to a mixer and mixed evenly. Then, a polysiloxane with monoamino end-capsulation, fluorine-containing side chains, and cyclic hard segments is added and mixed evenly. The hot melt is removed, cooled, and crushed to obtain polysiloxane-grafted EVA with fluorine-containing side chains and cyclic hard segments, which is the heat-resistant hydrophobic modified masterbatch. The mass ratio of maleic anhydride-grafted EVA to polysiloxane with monoamino end-capsulation, fluorine-containing side chains, and cyclic hard segments is 100:(12~150).

2. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 1, characterized in that, The Boc-amino-terminated polysiloxane with Si-H side chains has a molecular weight of 3000~15000 g / mol.

3. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 1, characterized in that, The grafting rate of maleic anhydride in maleic anhydride-grafted EVA is 0.8~1.5wt%.

4. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 1, characterized in that, The ethylene-vinyl acetate copolymer has a vinyl acetate content of 6-15 wt% and a melt index of 1.8-25 g / 10 min at 190°C and 2.16 kg.

5. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 1, characterized in that, The compatibilizer is maleic anhydride-grafted EVA; the lubricant is at least one of zinc stearate, calcium stearate, and stearic acid; the antioxidant is at least one of antioxidant 1010 and antioxidant 168; the antibacterial and antifungal masterbatch is a compound of inorganic zinc-based antibacterial agent and organic antifungal agent, and the carrier is EVA.

6. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 1, characterized in that, The mica powder is surface modified with an aminosilane coupling agent, and the amount of the aminosilane coupling agent added is 1 to 3 wt% of the mica powder.

7. The method for preparing the environmentally friendly anti-mildew and hydrophobic EVA composition according to any one of claims 1 to 6, characterized in that, Includes the following steps: Ethylene-vinyl acetate copolymer, compatibilizer, heat-resistant hydrophobic modified masterbatch, mica powder, antibacterial and antifungal masterbatch, lubricant, and antioxidant are mixed in proportion and stirred to obtain a semi-gelatinized mixture. The semi-gelatinized mixture is sheared and kneaded to obtain granules. The obtained granules are filtered to obtain an environmentally friendly antifungal and hydrophobic EVA composition.

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