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

Abstract

The invention discloses an environment-friendly mildewproof hydrophobic EVA composition and a preparation method thereof, and belongs to the technical field of plastics, the environment-friendly mildewproof hydrophobic EVA composition provided by the invention comprises the following components: 80-100 parts of an ethylene-vinyl acetate copolymer, 3-8 parts of a compatilizer, 10-20 parts of heat-resistant hydrophobic modified master batch, 10-30 parts of mica powder, 2-10 parts of antibacterial mildewproof master batch, and 0.1-2 parts of a lubricant, the heat-resistant hydrophobic modified master batch is polysiloxane grafted EVA (Ethylene Vinyl Acetate) of which the side chain contains fluorine and an annular hard segment. The EVA composition provided by the invention has good tensile strength, hydrophobic effect, antibacterial and mildew-proof performance and heat resistance, and is suitable for serving as a material such as a shower curtain serving in a high-temperature and high-humidity environment for a long time.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of plastics, in particular to an environment-friendly mildew-proof and hydrophobic EVA composition and a preparation method thereof. BACKGROUND

[0002] EVA (ethylene-vinyl acetate copolymer) is a high polymer material obtained by polymerizing a large amount of ethylene and vinyl acetate under high pressure, which has good elasticity and softness, excellent optical and mechanical properties, and good processing performance, and is widely used in adhesive, sports protection, automotive interior, electrical insulation material, packaging material, functional composite material and other fields. The film made of EVA has no irritating odor, good waterproof performance, good corrosion resistance, good softness and good drape, and is more suitable for use as a shower curtain in a home environment than traditional cloth and PVC. However, plastic materials are prone to attract the growth of bacteria or mold and other microorganisms in a high-temperature and humid environment, which can cause the plastic to discolor, degrade and produce an odor, and the strength of the EVA film will also decrease. Therefore, it is still necessary to develop an EVA composition with environment-friendly, mildew-proof and hydrophobic properties. SUMMARY

[0003] In order to overcome the deficiencies of the prior art, the present application provides an environment-friendly mildew-proof and hydrophobic EVA composition and a preparation method thereof.

[0004] The technical solution for achieving the purpose of the present application is as follows: An environment-friendly mildew-proof and hydrophobic EVA composition, calculated in terms of weight fraction, comprises the following components: ethylene-vinyl acetate copolymer 80-100 parts, compatibilizer 3-8 parts, heat-resistant and hydrophobic modified masterbatch 10-20 parts, mica powder 10-30 parts, antibacterial and mildew-proof masterbatch 2-10 parts, lubricant 0.1-2 parts, and antioxidant 0.1-1 part, wherein the heat-resistant and hydrophobic modified masterbatch is a polysiloxane grafted EVA with fluorine-containing side chains and cyclic hard segments.

[0005] In a specific embodiment, the preparation method of the heat-resistant and hydrophobic modified masterbatch comprises the following steps: S1. Mixing octamethylcyclotetrasiloxane, tetramethylcyclotetrasiloxane and trimethylsilanol, and performing an anionic ring-opening polymerization reaction under the action of a hexane solution containing n-butyllithium, to obtain a Boc-amino-terminated polysiloxane with Si-H side chains using N-Boc-3-chlorodimethylsilylpropylamine as a capping agent; S2. Adding Karstedt catalyst to the Boc-amino-terminated, side-chain containing Si-H polysiloxane solution, adding 2-perfluorohexylethyl methacrylate, isobornyl methacrylate to the Boc-amino-terminated, side-chain containing Si-H polysiloxane solution for silicon hydrogen addition, removing the amino protection with trifluoroacetic acid / methylene chloride solution, to obtain a mono-amino-terminated, side-chain containing fluorine and cyclic hard segment polysiloxane; S3. Adding maleic anhydride grafted EVA, antioxidant and catalyst into a mixing mill to mix uniformly, adding the mono-amino-terminated, side-chain containing fluorine and cyclic hard segment polysiloxane to continue mixing uniformly, taking out the hot melt and cooling and crushing to obtain a side-chain containing fluorine and cyclic hard segment polysiloxane grafted EVA, which is a heat-resistant and hydrophobic modified masterbatch.

[0006] 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).

[0007] In one specific embodiment, N-Boc-3-chlorodimethylsilylpropylamine is a compound with the following structure: .

[0008] In one specific embodiment, the molecular weight of the Boc-amino-terminated, side-chain containing Si-H polysiloxane is 3000-15000 g / mol.

[0009] In one specific embodiment, the molar ratio of 2-perfluorohexylethyl methacrylate, isobornyl methacrylate is (6-8):(2-4).

[0010] In one specific embodiment, the grafting rate of maleic anhydride in the maleic anhydride grafted EVA is 0.8-1.5 wt%, and the mass ratio of the maleic anhydride grafted EVA and the mono-amino-terminated, side-chain containing fluorine and cyclic hard segment polysiloxane is 100:(12-150).

[0011] In one specific embodiment, 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 under a load of 2.16 kg.

[0012] In one specific embodiment, the compatilizer is maleic anhydride grafted EVA; the lubricant is at least one of zinc stearate, calcium stearate, stearic acid; the antioxidant is at least one of antioxidant 1010, antioxidant 168; the antibacterial and mildew-proof master batch is a complex of inorganic zinc antibacterial agent and organic mildew-proof agent, and the carrier is EVA.

[0013] In one specific embodiment, the mica powder is surface modified by amino silane coupling agent, and the addition amount of the amino silane coupling agent is 1-3 wt% of the mica powder.

[0014] The application also protects a preparation method of the environment-friendly mildew-proof and hydrophobic EVA composition, which comprises the following steps: mixing ethylene-vinyl acetate copolymer, a compatilizer, a heat-resistant and hydrophobic modified master batch, mica powder, an antibacterial and mildew-proof master batch, a lubricant and an antioxidant according to proportions, and stirring to obtain a semi-gel mixture; shearing and mixing the semi-gel mixture to obtain gel particles; filtering the obtained gel particles; and obtaining the environment-friendly mildew-proof and hydrophobic EVA composition.

[0015] Preferably, the stirring speed is 500-1000 rpm, and the stirring temperature is 85-105 DEG C.

[0016] Preferably, the filtering is performed by using a filter machine, the filter machine is used to filter the gel particles by using a filter screen with a mesh size of 80-200, and the screw speed of the filter machine is controlled to be below 60 rpm.

[0017] Beneficial effects

[0018] The application provides an environment-friendly mildew-proof and hydrophobic EVA composition and a preparation method thereof. The modified polysiloxane and the maleic anhydride grafted EVA are connected through amide bond reaction, and the problem of phase separation of the polysiloxane and the EVA directly blended is solved through the chemical crosslinking mode. Meanwhile, the fluorine-containing chain segment and the cyclic hard segment are grafted on the side chain of the polysiloxane, the surface energy of the EVA material is reduced, the hydrophobic property and the heat resistance of the EVA material are improved, and the EVA material is suitable for application in a long-term high-temperature and high-humidity environment. In addition, the mica powder treated by the amino silane coupling agent is added, which not only brings the pearlescent effect to the transparent EVA material itself, meets the aesthetic requirement of the material, but also reacts and crosslinks with the maleic anhydride groups on the compatilizer maleic anhydride grafted EVA and the maleic anhydride groups not consumed in the heat-resistant and hydrophobic master batch, and further improves the mechanical property of the material. BRIEF DESCRIPTION OF DRAWINGS

[0019] Figure 1 The synthesis path diagram of the polysiloxane grafted EVA with the side chain containing fluorine and cyclic hard segment is shown in the figure. Figure 2 The nuclear magnetic hydrogen spectrum of N-Boc-3-chlorodimethylsilylpropylamine is shown in the figure. Figure 3The infrared spectrogram of the Boc-amino-terminated polysiloxane, the single-amino-terminated polysiloxane with fluorine-containing side chains and cyclic hard segments, and the heat-resistant hydrophobic modified master batch 1. DETAILED DESCRIPTION

[0020] The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative work fall within the protection scope of the present application.

[0021] In the embodiments, the experimental methods used are conventional methods, and the materials and reagents used are commercially available unless otherwise specified.

[0022] The raw materials used in the embodiments and comparative examples are described as follows. Ethylene-vinyl acetate copolymer: the content of vinyl acetate is 9wt%, the melt index is 2g / 10min under the condition of 190℃ and 2.16kg; the grade is 155, Yanshan Petrochemical; Maleic anhydride grafted EVA: ST-3, grafting rate: 1.0-1.4wt%, melt index (190℃, 2.16kg): 0.8-1.5g / 10min, Nanjing Plastech; Antibacterial and mildew-proof master batch: inorganic zinc-based antibacterial agent and organic mildew-proof agent, EVA as carrier, HY-FM03, Shenzhen Hengyang Nanometer Material Co., Ltd.; Mica powder: synthetic mica powder, 600 mesh, China Crystal New Material Holding Co., Ltd.; prepared by wet surface modification with 1.2% amino silane coupling agent (KH-550), the specific preparation steps are as follows: the mica powder is dried at 110℃ for 60min, a pre-hydrolysis solution is prepared: 240ml of anhydrous ethanol and 60ml of deionized water are mixed, glacial acetic acid is added to adjust the pH to 3.5-4, 120g of amino silane coupling agent KH-550 is added, and stirring is carried out in a 60℃ water bath for 10min until it is clear, 10kg of hot mica powder is put into a high-speed mixer, the temperature is set at 60℃, the speed is 300rpm, the pre-hydrolysis solution is uniformly sprayed in 3-5min by using a peristaltic pump, and stirring is continued for 15min, after discharging, it is dried at 80℃ for 30min, and then sieved through a 100 mesh sieve to obtain the surface-treated mica powder.

[0023] Lubricant: calcium stearate, commercially available; Antioxidant: a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1, commercially available; Amino capping agent: 1 mol allylamine, 1.1 mol triethylamine were dissolved in tetrahydrofuran to prepare a solution with a total concentration of 1 mol / L, 1.05 mol di-tert-butyl dicarbonate was dissolved in tetrahydrofuran to prepare a solution with a concentration of 1 mol / L, the di-tert-butyl dicarbonate solution was added dropwise into the allylamine solution under ice bath conditions, stirred uniformly, the ice bath was removed and stirring was continued at room temperature for 3 hours, washed with deionized water and saturated sodium bicarbonate solution in sequence, dried after rotary evaporation at 35°C to obtain N-Boc-allylamine, with a yield of 90.2%.

[0024] Under anhydrous and light-proof conditions, 1 mol of N-Boc-allylamine was dissolved in tetrahydrofuran to prepare a solution with a concentration of 1 mol / L, 1 mol of dimethyl monochlorosilane was dissolved in tetrahydrofuran to prepare a solution with a concentration of 1 mol / L, isopropyl chloroplatinic acid solution containing 10 ppm Pt was added to the N-Boc-allylamine solution, and the dimethyl monochlorosilane solution was added dropwise into the N-Boc-allylamine solution within 30 min under ice bath conditions, the temperature was raised to 35°C after stirring for 5 min, and the reaction was carried out in the dark for 2 hours, 1H NMR confirmed that δ4.7 (Si-H) disappeared, the reaction was stopped, platinum was removed by filtration, and the solvent was removed after rotary evaporation at 30°C under reduced pressure to obtain N-Boc-3-chlorodimethylsilylpropylamine, with a yield of 82.3%. The structure was confirmed by 1H NMR as shown in Figure 2 .

[0025] Heat-resistant hydrophobic modification master batch 1: self-made, the preparation method is as follows: S1. The reaction container and raw materials were pre-dried to remove water and filled with nitrogen to ensure that the reaction system was free of water and oxygen. Under a nitrogen atmosphere, 1.05 mol of trimethylsilanol, 0.85 mol of octamethylcyclotetrasiloxane, 0.15 mol of tetramethylcyclotetrasiloxane, and 300 ml of anhydrous tetrahydrofuran were added to the reaction container, cooled to -10°C, and 170 ml of a n-butyllithium ethane solution with a concentration of 2.5 mol / L was slowly added to the reaction system using a syringe, with the addition being completed within 15 min, stirring was maintained at -10°C for 30 min, the temperature was naturally raised to 25°C, and stirring was continued for 3 h, the temperature was again lowered to 0°C, 1 mol of N-Boc-3-chlorodimethylsilylpropylamine (diluted with 200 ml of tetrahydrofuran) was added dropwise using a syringe, stirred for 30 min, 5 mL of deionized water was added to quench the reaction using a syringe, stirred for 5 min, the organic layer was separated, washed once with 100 ml of saturated sodium bicarbonate solution and 100 ml of saturated sodium chloride solution, and dried over anhydrous magnesium sulfate; the residual monomers and solvents were removed by oil pump at 0.5 mbar, 30°C for 2 h to obtain Boc-amino-capped, side-chain Si-H-containing polysiloxane; the molecular weight was detected by GPC to be 5800 g / mol.

[0026] 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. 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.

[0027] 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 3It can be seen that the infrared absorption peaks of Boc-amino-terminated -NH group, C=0 group and side chain Si-H group are detected in the Boc-amino-terminated polysiloxane with Si-H containing side chain, indicating the successful preparation of the Boc-amino-terminated polysiloxane with Si-H containing side chain. The infrared absorption peak of -NH2 is detected in the mono-amino-terminated polysiloxane with fluorine containing side chain and cyclic hard segment, and the Si-H peak disappears, proving the successful preparation of the mono-amino-terminated polysiloxane with fluorine containing side chain and cyclic hard segment. The infrared characteristic peaks of Si-O-Si and Si-C in the siloxane segment are detected in the heat-resistant and hydrophobic modified master batch, i.e. the polysiloxane with fluorine containing side chain and cyclic hard segment, indicating the successful preparation of the heat-resistant and hydrophobic modified master batch 1.

[0028] Heat-resistant and hydrophobic modified master batch 2: compared with the heat-resistant and hydrophobic modified master batch 1, the difference lies in that the addition amount of octamethylcyclotetrasiloxane in step S1 is modified to 0.7 mol, the addition amount of tetramethylcyclotetrasiloxane is modified to 0.3 mol, and the molecular weight of the Boc-amino-terminated polysiloxane with Si-H containing side chain detected by GPC is 6200 g / mol.

[0029] Heat-resistant and hydrophobic modified master batch 3: compared with the heat-resistant and hydrophobic modified master batch 1, the difference lies in that the addition amount of octamethylcyclotetrasiloxane in step S1 is modified to 0.9 mol, the addition amount of tetramethylcyclotetrasiloxane is modified to 0.1 mol, and the molecular weight of the Boc-amino-terminated polysiloxane with Si-H containing side chain detected by GPC is 5400 g / mol.

[0030] Heat-resistant and hydrophobic modified master batch 4: compared with the heat-resistant and hydrophobic modified master batch 1, the difference lies in that the addition amount of trimethylsilanol in step S1 is modified to 2.1 mol, the addition amount of N-Boc-3-chlorodimethylsilylpropylamine is modified to 2 mol, and the molecular weight of the Boc-amino-terminated polysiloxane with Si-H containing side chain detected by GPC is 3000 g / mol.

[0031] Heat-resistant and hydrophobic modified master batch 5: compared with the heat-resistant and hydrophobic modified master batch 1, the difference lies in that the addition amount of 2-perfluorohexylethyl methacrylate in step S2 is modified to 0.48 mol, and the addition amount of isobornyl methacrylate is modified to 0.12 mol.

[0032] Heat-resistant and hydrophobic modified master batch 6: compared with the heat-resistant and hydrophobic modified master batch 1, the difference lies in that the addition amount of 2-perfluorohexylethyl methacrylate in step S2 is modified to 0.6 mol, and no isobornyl methacrylate is added.

[0033] Heat-resistant and hydrophobic modified master batch 7: compared with the heat-resistant and hydrophobic modified master batch 1, the difference lies in that no 2-perfluorohexylethyl methacrylate is added in step S2, and the addition amount of isobornyl methacrylate is modified to 0.6 mol.

[0034] 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 the masterbatch shows obvious phase separation.

[0035] The component raw materials used in the embodiments and comparative examples of the present application are commercially available raw materials unless otherwise specified, and the component raw materials used in each parallel experiment are all the same.

[0036] Examples and comparative examples An environmentally friendly mildew-resistant hydrophobic EVA composition, and a preparation method thereof, includes the following steps: mixing ethylene-vinyl acetate copolymer, a compatibilizer, a heat-resistant hydrophobic modified masterbatch, mica powder, an antibacterial and mildew-resistant masterbatch, a lubricant, and an antioxidant in a proportion, and stirring to obtain a semi-gel mixture; shearing and mixing the semi-gel mixture to obtain a gel particle; filtering the obtained gel particle; obtaining the environmentally friendly mildew-resistant hydrophobic EVA composition; the stirring speed is 800 rpm, and the stirring temperature is 105°C; the filtering is performed by using a filter machine, the filter machine uses a 100-mesh filter screen to filter the gel particle, and the screw speed of the filter machine is controlled at 40 rpm; and the specific components and proportions of the antibacterial and mildew-resistant EVA composition are shown in Table 1. Table 1 Specific components and proportions of the environmentally friendly mildew-resistant hydrophobic EVA composition

[0037] The environmentally friendly mildew-resistant hydrophobic EVA composition gel particle is formed by using a casting machine, and the gel particle is pushed to the die head of the casting machine for extrusion molding, wherein the temperature difference between the die head of the casting machine and the cooling roller is not less than 40°C; a sheet with a thickness of 0.15 mm is obtained; and the following performance tests are performed on the obtained sheet, and the results are shown in Table 2. (1) Tensile strength: the tensile properties of the sheet are tested according to ISO 527-2012 "Determination of tensile properties of plastics", 23°C, and the tensile rate is 50 mm / min; (2) Surface energy: the surface energy of the sheet is tested according to the GB / T 30693-2014 standard; (3) Hydrophobic property: the hydrophobic effect of the sheet is evaluated by measuring the water contact angle of the sheet in air, the greater the contact angle, the more difficult the sheet surface is wetted, and the better the hydrophobic effect; (4) Antibacterial rate: refer to QB / T 2591-2003 Appendix A to test and calculate at 28℃, wherein the antibacterial rate calculation formula is: R (%) = (B-C) / B x 100, wherein: R-antibacterial rate (%), B-average recovery bacteria number of blank control sample (cfu / piece), C-average recovery bacteria number of antibacterial plastic sample (cf / piece); test bacteria: Escherichia coli ATCC 8739, Staphylococcus aureus ATCC 6538P; (5) Antimold grade: refer to QB / T 2591-2003 Appendix B to test and grade at 28℃, wherein the sample mold growth grade is: 0 level-no growth, i.e. no growth observed under microscope (50 times magnification); 1 level-trace growth, i.e. visible growth with naked eye, but growth coverage area is less than 10%; 2 level-growth coverage area is not less than 10%, test mold: Trichoderma viride ATCC 9645, Aspergillus brasiliensis ATCC 9642, Chaetomium globosum ATCC 6205, Blastocladia tenella ATCC 15233.

[0038] (6) Heat aging resistance: put the sheet into a wet heat aging oven at 85℃, 85% RH for 1000 h, then take out and detect the tensile strength retention rate relative to the tensile strength before aging.

[0039] Table 2 Performance test results of environmentally friendly mold-resistant hydrophobic EVA composition

[0040] As can be seen from the data of the examples and comparative examples, the EVA composition provided by the present application has good tensile strength, hydrophobicity, antibacterial and mold-resistant properties and heat resistance, which meets the application requirements of materials in high temperature and high humidity environment such as shower curtain.

[0041] The preferred embodiments disclosed above are only used to help explain the present application. The preferred embodiments do not describe all the details, nor limit the application to the specific embodiments described. Obviously, many modifications and variations can be made according to the content of the present application. The present application selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present application, so that those skilled in the art can well understand and utilize the present application. The present application 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 fluorinated side chains and cyclic hard segments.

2. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 1, characterized in that, 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, with N-Boc-3-chlorodimethylsilylpropylamine as the end-capping agent, to obtain a polysiloxane with Boc-amino end-capping and Si-H side chain. 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. 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.

3. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 2, characterized in that, 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).

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

5. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 2, characterized in that, The molar ratio of 2-perfluorohexylethyl methacrylate to isobornyl methacrylate is (6~8):(2~4).

6. The environmentally friendly, mildew-resistant, and hydrophobic EVA composition as described in claim 2, characterized in that, The maleic anhydride grafting rate in maleic anhydride-grafted EVA is 0.8~1.5wt%, and the mass ratio of maleic anhydride-grafted EVA to monoamino-terminated, fluorinated side-chain polysiloxane with cyclic hard segments is 100:(12~150).

7. 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.

8. 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.

9. 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.

10. The method for preparing the environmentally friendly anti-mildew and hydrophobic EVA composition according to any one of claims 1 to 9, 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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