Flame-retardant PVC film and preparation method thereof
By introducing phosphite and modified silica into PVC film, and combining the reaction of metal ions with polyvinyl chloride, a PVC film with anti-aging, flame retardant and self-healing properties is prepared, which solves the problems of easy aging and flammability of PVC material and improves the heat resistance and combustion inhibition ability of the material.
Patent Information
- Application Number
- CN202512024932.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-30
- Publication Date
- 2026-02-13
AI Technical Summary
PVC material is prone to aging and is not flame retardant. When burning, it releases toxic gases and can easily accelerate the spread of fire.
Phosphite was prepared by reacting 4'-vinyl-[1,1'-biphenyl]-4-ol with phosphorus trichloride, modified silica was prepared by reacting nano-silica with trimethoxysilane and phosphite, and modified polyvinyl chloride was prepared by reacting polyvinyl chloride with 3-hydroxy-4-pentenoic acid, calcium hydroxide, and zinc hydroxide. After mixing, polyethylene glycol methacrylate was polymerized on the membrane surface to form a flame-retardant PVC film.
It achieves anti-aging, flame retardant and self-healing effects on PVC film. Through the antioxidant effect of phosphite and the self-healing mechanism of metal ions, it improves the heat resistance and combustion inhibition ability of the material.
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Abstract
Description
Technical Field
[0001] This invention relates to the field of membrane materials, specifically to a flame-retardant PVC membrane and its preparation method. Background Technology
[0002] PVC's main component is polyvinyl chloride, a thermoplastic plastic polymerized from vinyl chloride. It appears as a white powder or translucent granules. It is produced by adding plasticizers, stabilizers, and other additives, and then processing it through calendering or blow molding. After film formation, it is slightly yellow and translucent with a glossy finish. Its transparency is better than that of polyethylene and polypropylene. It is commonly used in sheets, pipes, shoe soles, toys, doors and windows, wire sheaths, stationery, etc., and is a widely used polymer material in daily life.
[0003] However, PVC molecules contain a large number of chlorine atoms, which are prone to degradation under the influence of light, heat, and oxygen, leading to brittleness, powdering, and even cracking. Its oxidative weakness in molecular structure makes it more prone to aging than materials such as polyethylene. Furthermore, PVC itself is not flame retardant and is easily combustible in open flames, releasing toxic gases. Ordinary PVC products may accelerate the spread of fire in a fire and produce dense smoke, hindering rescue efforts. Therefore, this application introduces a flame-retardant PVC film with aging resistance and its preparation method. Summary of the Invention
[0004] The purpose of this invention is to provide a flame-retardant PVC film and its preparation method to solve the problems existing in the prior art.
[0005] A flame-retardant PVC film is prepared by mixing ACR-Z30, modified polyvinyl chloride and modified silica to form a film, and then polymerizing polyethylene glycol methacrylate on the film surface. The modified silica is prepared by reacting nano-silica sequentially with trimethoxysilane and phosphite; The phosphite is prepared by reacting 4'-vinyl-[1,1'-biphenyl]-4-ol with phosphorus trichloride; The modified polyvinyl chloride is prepared by reacting polyvinyl chloride with 3-hydroxy-4-pentenoic acid, followed by calcium hydroxide and zinc hydroxide.
[0006] A method for preparing a flame-retardant PVC film, the method mainly comprising the following preparation steps: (1) Prepare a chloroplatinic acid solution with a concentration of 0.009~0.011 g / ml by mixing chloroplatinic acid and isopropanol; mix the pre-modified silica, phosphite, isopropanol and chloroplatinic acid solution at a mass ratio of 1:1.4~1.6:7~8:0.04~0.06, stir at 64~66℃ and 200~300 r / min for 4.5~5.5 h, filter, wash with deionized water 4~6 times, and vacuum dry at 30~40℃ for 24~26 h to obtain modified silica; (2) Mix calcium hydroxide, zinc hydroxide and deionized water in a molar ratio of 23~25:38~42:580~620, sonicate for 2~3 min to obtain an alkaline solution; immerse the pre-modified polyvinyl chloride in the alkaline solution, heat to 68~72℃, stir at 80~100 r / min for 2~3 h, filter, wash with deionized water 7~9 times, and vacuum dry at 40~44℃ for 24~26 h to obtain modified polyvinyl chloride; (3) Immerse the polyvinyl chloride film in the surface treatment solution, let it stand at 61~65℃ for 7~9h, wash it with ethanol 4~6 times, and vacuum dry it at 35~45℃ for 24~26h to obtain the modified polyvinyl chloride film.
[0007] As an optimization, the pre-modified silica in step (1) is prepared by mixing nano-silica and toluene at a mass ratio of 1:24~26, sonicating for 28~32 min, uniformly adding 1.4~1.6 times the mass of nano-silica to trimethoxysilane within 2~3 min, stirring at 68~72℃ and 200~300 r / min for 17~19 h, filtering, washing with ethanol 5~7 times, and vacuum drying at 30~40℃ for 24~26 h.
[0008] As an optimization, the phosphite in step (1) is prepared by mixing phosphorus trichloride and chloroform at a mass ratio of 2.9~3.1:46~48, and sonicating for 14~16 min to obtain a phosphorus-chloride solution; the phosphorus-chloride solution is mixed with a phenol solution corresponding to 4'-vinyl-[1,1'-biphenyl]-4-ol at a molar amount of phosphorus trichloride of 2.9~3.1 times, stirred at 68~72℃ and 200~300 r / min for 6~7 h, cooled to room temperature, washed 7~9 times with deionized water, and vacuum dried at 40~50℃ for 46~48 h to obtain the final product.
[0009] As an optimization, the reaction principle of the phosphite is as follows:
[0010] As an optimization, the phenol solution is prepared by mixing 4'-vinyl-[1,1'-biphenyl]-4-ol and chloroform at a mass ratio of 1:48~50, sonicating for 14~16 min, then adding triethylamine at a molar amount of 1~1.2 times that of 4'-vinyl-[1,1'-biphenyl]-4-ol, and sonicating for 14~16 min.
[0011] As an optimization, the pre-modified polyvinyl chloride in step (2) is prepared by mixing 3-hydroxy-4-pentenoic acid and diethyl ether at a mass ratio of 1:8~10 and sonicating for 4~6 min to obtain a 3-hydroxy-4-pentenoic acid solution; mixing polyvinyl chloride, calcium carbonate and deionized water at a mass ratio of 4~6:2~3:20~30 and sonicating for 8~9 min; adding 2.8~3.2 times the mass of the 3-hydroxy-4-pentenoic acid solution of polyvinyl chloride; stirring at 200~300 r / min and 58~62℃ for 2~3 h; filtering; washing with acetic acid 9~11 times; washing with deionized water 4~6 times; and vacuum drying at 40~44℃ for 24~26 h to obtain the product.
[0012] As an optimization, the polyvinyl chloride is polyvinyl chloride of model SG-5.
[0013] As an optimization, the polyvinyl chloride film in step (3) is prepared by mixing ACR-Z30, modified polyvinyl chloride and modified silica at a mass ratio of 0.48~0.50:6~7:1, mixing them evenly in a high-speed mixer, placing them on a rolling mill for rolling at 168~172℃ for 4~6 minutes, hot pressing them on a flat vulcanizing machine at 178~182℃ for 7~9 minutes, and cold pressing them at room temperature for 4~6 minutes.
[0014] As an optimization, the surface treatment solution in step (3) is prepared by mixing polyethylene glycol methacrylate, ammonium persulfate and deionized water in a mass ratio of 14~16:1:83~85 and sonicating for 5~7 minutes.
[0015] Compared with the prior art, the beneficial effects achieved by the present invention are: In preparing a flame-retardant PVC film, this invention involves reacting 4'-vinyl-[1,1'-biphenyl]-4-ol with phosphorus trichloride to obtain phosphite; reacting nano-silica sequentially with trimethoxysilane and phosphite to obtain modified silica; reacting polyvinyl chloride first with 3-hydroxy-4-pentenoic acid, then with calcium hydroxide and zinc hydroxide to obtain modified polyvinyl chloride; mixing ACR-Z30, modified polyvinyl chloride, and modified silica to form a film; and then polymerizing polyethylene glycol methacrylate on the film surface to obtain a flame-retardant PVC film.
[0016] First, 4'-vinyl-[1,1'-biphenyl]-4-ol was reacted with phosphorus trichloride to prepare a phosphite ester. Then, nano-silica was reacted sequentially with trimethoxysilane and the phosphite ester to prepare modified silica. Next, 4'-vinyl-[1,1'-biphenyl]-4-ol was reacted with phosphorus trichloride to prepare another phosphite ester. Finally, 4'-vinyl-[1,1'-biphenyl]-4-ol was reacted with phosphorus trichloride to prepare a phosphite ester-based antioxidant. Phosphite ester-based antioxidants are a class of auxiliary antioxidants widely used in polymer materials. They can reduce hydroperoxides generated during oxidation to stable alcohols, while simultaneously being oxidized to phosphate esters themselves, thus preventing oxidation. Hydrogen peroxides decompose to generate more free radicals, thereby interrupting the oxidation chain reaction and achieving an anti-aging effect. At the same time, phosphites can decompose to produce volatile phosphides during high-temperature combustion. These volatile phosphides can capture active free radicals in the gas phase, thereby interrupting the combustion chain reaction. During the decomposition process, phosphites absorb a large amount of heat, reduce the temperature of the combustion zone, release non-combustible gases such as carbon dioxide, dilute the concentration of oxygen and combustible gases, and inhibit the spread of combustion, thus achieving a flame-retardant effect. Modified silica is prepared by reacting nano-silica sequentially with trimethoxysilane and phosphites. Finally, phosphites are grafted onto the silica surface through a hydrosilylation reaction.
[0017] Secondly, polyvinyl chloride (PVC) is reacted with 3-hydroxy-4-pentenoic acid, then with calcium hydroxide and zinc hydroxide to obtain modified PVC. ACR-Z30, modified PVC, and modified silica are mixed to form a film, which is then polymerized on the film surface using polyethylene glycol methacrylate to obtain a flame-retardant PVC film. Furthermore, PVC is reacted with 3-hydroxy-4-pentenoic acid, then with calcium hydroxide and zinc hydroxide to enrich the PVC with calcium-zinc soaps. The zinc soaps can rapidly absorb hydrogen chloride produced by PVC degradation, while the calcium soaps neutralize the hydrogen chloride and undergo a metathesis reaction with zinc chloride, a byproduct of hydrogen chloride absorption by the zinc soaps, to convert the zinc chloride into a more palatable form. The process involves reconverting the material into zinc soap, activating its stabilizing ability, and then combining the two with phosphite to achieve anti-aging effects. Simultaneously, metal ions are introduced into the polymer matrix, achieving a self-repairing effect through coordination between the metal ions and the carboxyl groups within the polyvinyl chloride (PVC). ACR-Z30, modified PVC, and modified silica are mixed to form a film, which is then polymerized on the film surface using polyethylene glycol methacrylate. Finally, a hydrophilic material is polymerized on the film surface through the polymerization of the double bonds on the modified PVC and modified silica with polyethylene glycol methacrylate. This process imparts both antistatic and antifouling properties to the film. Detailed Implementation
[0018] 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. Example 1:
[0019] A method for preparing a flame-retardant PVC film mainly includes the following preparation steps: (1) Mix 4'-vinyl-[1,1'-biphenyl]-4-ol and chloroform at a mass ratio of 1:48, sonicate for 14 min, then add triethylamine equal to the molar amount of 4'-vinyl-[1,1'-biphenyl]-4-ol, sonicate for 14 min to obtain a phenol solution; mix phosphorus trichloride and chloroform at a mass ratio of 2.9:46, sonicate for 14 min to obtain a phosphorus-chloride solution; mix the phosphorus-chloride solution with the corresponding phenol solution of 4'-vinyl-[1,1'-biphenyl]-4-ol equal to the molar amount of phosphorus trichloride, stir at 68℃ and 200 r / min for 6 h, cool to room temperature, wash 7 times with deionized water, and vacuum dry at 40℃ for 46 h to obtain phosphite; nano-dioxide Silicon and toluene were mixed at a mass ratio of 1:24 and sonicated for 28 min. Trimethoxysilane, at a mass ratio of 1.4 times that of nano-silica, was added uniformly over 2 min. The mixture was stirred at 68 °C and 200 r / min for 17 h, filtered, washed five times with ethanol, and vacuum dried at 30 °C for 24 h to obtain pre-modified silica. A chloroplatinic acid solution with a concentration of 0.009 g / ml was prepared by mixing chloroplatinic acid and isopropanol. The pre-modified silica, phosphite, isopropanol, and chloroplatinic acid solution were mixed at a mass ratio of 1:1.4:7:0.04, stirred at 64 °C and 200 r / min for 4.5 h, filtered, washed four times with deionized water, and vacuum dried at 30 °C for 24 h to obtain modified silica. (2) 3-hydroxy-4-pentenoic acid and diethyl ether were mixed at a mass ratio of 1:8 and sonicated for 4 min to obtain a 3-hydroxy-4-pentenoic acid solution; polyvinyl chloride, calcium carbonate and deionized water were mixed at a mass ratio of 4:2:20 and sonicated for 8 min; 2.8 times the mass of polyvinyl chloride in the 3-hydroxy-4-pentenoic acid solution was added; the mixture was stirred at 200 r / min and 58 °C for 2 h; filtered; washed 9 times with acetic acid; washed 4 times with deionized water; and vacuum dried at 40 °C for 24 h to obtain pre-modified polyvinyl chloride; calcium hydroxide, zinc hydroxide and deionized water were mixed at a molar ratio of 23:38:580 and sonicated for 2 min to obtain an alkaline solution; the pre-modified polyvinyl chloride was immersed in the alkaline solution; the temperature was raised to 68 °C; the mixture was stirred at 80 r / min for 2 h; filtered; washed 7 times with deionized water; and vacuum dried at 40 °C for 24 h to obtain modified polyvinyl chloride; (3) Mix ACR-Z30, modified polyvinyl chloride and modified silica at a mass ratio of 0.48:6:1, mix evenly in a high-speed mixer, place on a two-roll mill for two-roll milling, mill at 168℃ for 4 min, hot press at 182℃ on a flat vulcanizing machine for 7 min, and cold press at room temperature for 4 min to obtain polyvinyl chloride film; mix polyethylene glycol methacrylate, ammonium persulfate and deionized water at a mass ratio of 14:1:83, sonicate for 5 min to obtain surface treatment solution; immerse polyvinyl chloride film in surface treatment solution, stand at 61℃ for 7 h, wash with ethanol 4 times, vacuum dry at 35℃ for 24 h to obtain modified polyvinyl chloride film. Example 2:
[0020] A method for preparing a flame-retardant PVC film mainly includes the following preparation steps: (1) Mix 4'-vinyl-[1,1'-biphenyl]-4-ol and chloroform at a mass ratio of 1:49, sonicate for 15 min, then add triethylamine at a molar ratio of 1.1 times that of 4'-vinyl-[1,1'-biphenyl]-4-ol, sonicate for 15 min to obtain a phenol solution; mix phosphorus trichloride and chloroform at a mass ratio of 3:47, sonicate for 15 min to obtain a phosphorus-chloride solution; mix the phosphorus-chloride solution with the corresponding phenol solution of 4'-vinyl-[1,1'-biphenyl]-4-ol at a molar ratio of 3 times that of phosphorus trichloride, stir at 70℃ and 250 r / min for 6.5 h, cool to room temperature, wash 8 times with deionized water, and vacuum dry at 45℃ for 47 h to obtain phosphite; nano silica Pre-modified silica was prepared by mixing with toluene at a mass ratio of 1:25, sonicating for 30 min, adding trimethoxysilane at a rate of 1.5 times its mass over 2.5 min, stirring at 70 °C and 250 r / min for 18 h, filtering, washing 6 times with ethanol, and vacuum drying at 35 °C for 25 h. A chloroplatinic acid solution with a concentration of 0.01 g / ml was prepared by mixing chloroplatinic acid and isopropanol. The pre-modified silica, phosphite, isopropanol, and chloroplatinic acid solution were mixed at a mass ratio of 1:1.5:7.5:0.05, stirred at 65 °C and 250 r / min for 5 h, filtered, washed 5 times with deionized water, and vacuum drying at 35 °C for 25 h. (2) Mix 3-hydroxy-4-pentenoic acid and diethyl ether at a mass ratio of 1:9, sonicate for 5 min to obtain a 3-hydroxy-4-pentenoic acid solution; mix polyvinyl chloride, calcium carbonate and deionized water at a mass ratio of 5:2.5:25, sonicate for 8.5 min, add 3 times the mass of polyvinyl chloride in the 3-hydroxy-4-pentenoic acid solution, stir at 250 r / min and 60 °C for 2.5 h, filter, wash 10 times with acetic acid, wash 5 times with deionized water, and vacuum dry at 42 °C for 25 h to obtain pre-modified polyvinyl chloride; mix calcium hydroxide, zinc hydroxide and deionized water at a molar ratio of 24:40:600, sonicate for 2.5 min to obtain an alkaline solution; immerse the pre-modified polyvinyl chloride in the alkaline solution, heat to 70 °C, stir at 90 r / min for 2.5 h, filter, wash 8 times with deionized water, and vacuum dry at 42 °C for 25 h to obtain modified polyvinyl chloride; (3) Mix ACR-Z30, modified polyvinyl chloride and modified silica at a mass ratio of 0.49:6.5:1, mix evenly in a high-speed mixer, place on a two-roll mill for two-roll milling, mill at 170℃ for 5 min, hot press at 180℃ on a flat vulcanizing machine for 8 min, and cold press at room temperature for 5 min to obtain polyvinyl chloride film; mix polyethylene glycol methacrylate, ammonium persulfate and deionized water at a mass ratio of 15:1:84, sonicate for 6 min to obtain surface treatment solution; immerse polyvinyl chloride film in surface treatment solution, stand at 64℃ for 8 h, wash with ethanol 5 times, vacuum dry at 40℃ for 25 h to obtain modified polyvinyl chloride film. Example 3:
[0021] A method for preparing a flame-retardant PVC film mainly includes the following preparation steps: (1) Mix 4'-vinyl-[1,1'-biphenyl]-4-ol and chloroform at a mass ratio of 1:50, sonicate for 16 min, then add triethylamine at a molar ratio of 1.2 times that of 4'-vinyl-[1,1'-biphenyl]-4-ol, sonicate for 16 min to obtain a phenol solution; mix phosphorus trichloride and chloroform at a mass ratio of 3.1:48, sonicate for 16 min to obtain a phosphorus-chloride solution; mix the phosphorus-chloride solution with the corresponding phenol solution of 4'-vinyl-[1,1'-biphenyl]-4-ol at a molar ratio of 3.1 times that of phosphorus trichloride, stir at 72℃ and 300 r / min for 7 h, cool to room temperature, wash 9 times with deionized water, and vacuum dry at 50℃ for 48 h to obtain phosphite; nano-dioxanone Pre-modified silica was prepared by mixing silicon dioxide and toluene at a mass ratio of 1:26, sonicating for 32 min, adding trimethoxysilane at a rate of 1.6 times the mass of nano-silica within 3 min, stirring at 72℃ and 300 r / min for 19 h, filtering, washing 7 times with ethanol, and vacuum drying at 40℃ for 26 h. Chloroplatinic acid and isopropanol were prepared to form a chloroplatinic acid solution with a concentration of 0.011 g / ml. The pre-modified silica, phosphite, isopropanol, and chloroplatinic acid solution were mixed at a mass ratio of 1:1.6:8:0.06, stirred at 66℃ and 300 r / min for 5.5 h, filtered, washed 6 times with deionized water, and vacuum drying at 40℃ for 26 h. (2) 3-hydroxy-4-pentenoic acid and diethyl ether were mixed at a mass ratio of 1:10 and sonicated for 6 min to obtain a 3-hydroxy-4-pentenoic acid solution; polyvinyl chloride, calcium carbonate and deionized water were mixed at a mass ratio of 6:3:30 and sonicated for 9 min; 3.2 times the mass of polyvinyl chloride in the 3-hydroxy-4-pentenoic acid solution was added; the mixture was stirred at 300 r / min and 62 °C for 3 h; filtered; washed 11 times with acetic acid; washed 6 times with deionized water; and vacuum dried at 44 °C for 26 h to obtain pre-modified polyvinyl chloride; calcium hydroxide, zinc hydroxide and deionized water were mixed at a molar ratio of 25:42:620 and sonicated for 3 min to obtain an alkaline solution; the pre-modified polyvinyl chloride was immersed in the alkaline solution; the temperature was raised to 72 °C; the mixture was stirred at 100 r / min for 3 h; filtered; washed 9 times with deionized water; and vacuum dried at 44 °C for 26 h to obtain modified polyvinyl chloride; (3) Mix ACR-Z30, modified polyvinyl chloride and modified silica at a mass ratio of 0.50:7:1, mix evenly in a high-speed mixer, place on a two-roll mill for two-roll milling, mill at 172℃ for 6 min, hot press at 182℃ on a flat vulcanizing machine for 9 min, and cold press at room temperature for 6 min to obtain polyvinyl chloride film; mix polyethylene glycol methacrylate, ammonium persulfate and deionized water at a mass ratio of 16:1:85, sonicate for 7 min to obtain surface treatment solution; immerse polyvinyl chloride film in surface treatment solution, stand at 65℃ for 9 h, wash with ethanol 6 times, vacuum dry at 45℃ for 26 h to obtain modified polyvinyl chloride film.
[0022] Comparative Example 1: The preparation method of the flame-retardant PVC film in Comparative Example 1 differs from that in Example 2 in that the nano-silica is not modified. The remaining steps are the same as in Example 2.
[0023] Comparative Example 2: The preparation method of the flame-retardant PVC film in Comparative Example 2 differs from that in Example 2 in that the polyvinyl chloride is not modified. The remaining steps are the same as in Example 2.
[0024] Comparative Example 3: The difference between the preparation method of the flame-retardant PVC film in Comparative Example 3 and Example 2 lies in step (3). Step (3) is modified as follows: ACR-Z30, modified polyvinyl chloride, and modified silica are mixed at a mass ratio of 0.49:6.5:1, mixed evenly in a high-speed mixer, and then rolled on a two-roll mill at 170°C for 5 minutes. The mixture is then hot-pressed at 180°C on a flat vulcanizing machine for 8 minutes and cold-pressed at room temperature for 5 minutes to obtain the modified polyvinyl chloride film. The remaining steps are the same as in Example 2.
[0025] Test Example 1: Hydrophilicity and flame retardancy tests: Hydrophilicity test method: The films prepared in each example and comparative example were made into samples with a length of 4cm and a width of 4cm. The hydrophilicity was tested using a contact angle meter. 10μL of water was dropped onto the sample surface at a time using a microsyringe. After standing for 30s, the water contact angle was measured and recorded using a contact angle meter. Flame retardancy test method: The limiting oxygen index of the films prepared in each example and comparative example was tested according to GB / T2406.2. The results are shown in Table 1.
[0026] Table 1
[0027] A comparison of the experimental data in Table 1 shows that the flame-retardant PVC film prepared by this invention has good hydrophilicity and flame-retardant properties.
[0028] A comparison of the experimental data from Examples 1, 2, and 3 and Comparative Example 1 in Table 1 reveals that Examples 1, 2, and 3 have high limiting oxygen indices. The difference between Comparative Example 1 and the Examples is that phosphite was not introduced onto the silica surface. This indicates that phosphite was prepared by reacting 4'-vinyl-[1,1'-biphenyl]-4-ol with phosphorus trichloride. Phosphite can decompose to produce volatile phosphides during high-temperature combustion. These volatile phosphides can capture active free radicals in the gas phase, thereby interrupting the chain reaction of combustion. During the decomposition process, phosphite absorbs a large amount of heat, reduces the temperature of the combustion zone, releases non-combustible gases such as carbon dioxide, dilutes the concentration of oxygen and combustible gases, inhibits the spread of combustion, and achieves a flame-retardant effect. A comparison of the experimental data from Examples 1, 2, 3 and Comparative Example 3 reveals that Examples 1, 2, and 3 have smaller water contact angles. The difference between Comparative Example 1 and the Examples is that polyethylene glycol methacrylate was not used for surface finishing, indicating that polymerizing a layer of hydrophilic material on the membrane surface can give the membrane a good hydrophilic effect.
[0029] Test Example 2: Self-healing test and aging resistance test Take the films prepared in each embodiment and comparative example and make them into samples with a length of 5cm, a width of 1cm and a thickness of 1mm. Test the tensile strength of the samples and record it as A0. Self-healing test method: Make a transverse cut of 0.5 cm in length and 0.5 mm in depth on the surface of the sample, let it stand at 70℃ for 24 h, test the tensile strength and record it as A1, calculate the self-healing retention rate, where self-healing retention rate = A1 / A0 × 100%; Aging resistance test method: The sample was placed in distilled water at 70℃ for wet heat aging, left to stand for 3 days, and the tensile strength was tested and recorded as A2. The antioxidant retention rate was calculated, where antioxidant retention rate = A2 / A0 × 100%. The results are shown in Table 2.
[0030] Table 2
[0031] A comparison of the experimental data in Table 2 shows that the flame-retardant PVC film prepared by this invention has good self-healing and aging resistance.
[0032] A comparison of the experimental data of Examples 1, 2, 3 and Comparative Example 1 in Table 2 reveals that Examples 1, 2, and 3 exhibit higher antioxidant retention rates. The difference between Comparative Example 1 and Examples 1, 2, and 3 lies in the absence of the introduction of phosphite through the reaction of 4'-vinyl-[1,1'-biphenyl]-4-ol and phosphorus trichloride. This indicates that phosphite can reduce the hydroperoxides generated during oxidation to stable alcohols, while simultaneously being oxidized to phosphate esters, preventing the decomposition of hydroperoxides and generating more free radicals, thereby interrupting the oxidation chain reaction and achieving an anti-aging effect. A comparison of the experimental data from Examples 1, 2, 3 and Comparative Example 2 reveals that Examples 1, 2, and 3 exhibit high antioxidant retention rates. The difference between Comparative Example 2 and Examples 1, 2, and 3 lies in the absence of modification of the polyvinyl chloride (PVC). This indicates that the introduction of calcium soap and zinc soap into PVC allows the zinc soap to rapidly absorb hydrogen chloride produced during PVC degradation. Calcium soap can neutralize the hydrogen chloride and also undergo a metathesis reaction with zinc chloride, a byproduct of the zinc soap's absorption of hydrogen chloride, converting the zinc chloride back into zinc soap and activating its stabilizing ability. The synergistic effect of both, along with the phosphite, achieves an anti-aging effect. A comparison of the experimental data from Examples 1, 2, 3 and Comparative Example 2 reveals that Examples 1, 2, and 3 exhibit high self-healing retention rates. The difference between Comparative Example 2 and Examples 1, 2, and 3 lies in the absence of modification of the polyvinyl chloride. This demonstrates that introducing metal ions into the polymer matrix and achieving self-healing effects through the coordination between the metal ions and the carboxyl groups within the polyvinyl chloride matrix is a significant advancement.
[0033] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A flame-retardant PVC film, characterized in that, The flame-retardant PVC film is prepared by mixing ACR-Z30, modified polyvinyl chloride and modified silica, forming a film, and then polymerizing polyethylene glycol methacrylate on the film surface. The modified silica is prepared by reacting nano-silica sequentially with trimethoxysilane and phosphite; The phosphite is prepared by reacting 4'-vinyl-[1,1'-biphenyl]-4-ol with phosphorus trichloride; The modified polyvinyl chloride is prepared by reacting polyvinyl chloride with 3-hydroxy-4-pentenoic acid, followed by calcium hydroxide and zinc hydroxide.
2. A method for preparing a flame-retardant PVC film, characterized in that, The preparation method of the flame-retardant PVC film mainly includes the following preparation steps: (1) Prepare a chloroplatinic acid solution with a concentration of 0.009~0.011 g / ml by mixing chloroplatinic acid and isopropanol; mix the pre-modified silica, phosphite, isopropanol and chloroplatinic acid solution, stir at 64~66℃ for 4.5~5.5 h, filter, wash with deionized water, and vacuum dry for 24~26 h to obtain modified silica; (2) Mix calcium hydroxide, zinc hydroxide and deionized water, sonicate to obtain an alkaline solution; immerse the pre-modified polyvinyl chloride in the alkaline solution, heat to 68~72℃, stir for 2~3h, filter, wash with deionized water, and vacuum dry for 24~26h to obtain modified polyvinyl chloride; (3) Immerse the polyvinyl chloride film in the surface treatment solution, let it stand at 61~65℃ for 7~9h, wash it with ethanol, and vacuum dry it for 24~26h to obtain the modified polyvinyl chloride film.
3. The method for preparing a flame-retardant PVC film according to claim 2, characterized in that, The pre-modified silica in step (1) is prepared by mixing nano-silica with toluene, sonicating, adding trimethoxysilane at a rate of 1.4 to 1.6 times the mass of nano-silica at a uniform rate within 2 to 3 minutes, stirring at 68 to 72°C for 17 to 19 hours, filtering, washing with ethanol, and vacuum drying for 24 to 26 hours.
4. The method for preparing a flame-retardant PVC film according to claim 2, characterized in that, The phosphite in step (1) is prepared by mixing phosphorus trichloride and chloroform, sonicating to obtain a phosphorus-chloride solution; mixing the phosphorus-chloride solution with a phenol solution corresponding to 4'-vinyl-[1,1'-biphenyl]-4-ol at 2.9 to 3.1 times the molar amount of phosphorus trichloride, stirring at 68 to 72°C for 6 to 7 hours, cooling to room temperature, washing with deionized water, and vacuum drying for 46 to 48 hours to obtain the phosphite.
5. The method for preparing a flame-retardant PVC film according to claim 4, characterized in that, The phenolic solution is prepared by mixing 4'-vinyl-[1,1'-biphenyl]-4-ol and chloroform, sonicating, then adding triethylamine in a molar amount of 1 to 1.2 times that of 4'-vinyl-[1,1'-biphenyl]-4-ol, and sonicating again.
6. The method for preparing a flame-retardant PVC film according to claim 2, characterized in that, The pre-modified polyvinyl chloride in step (2) is prepared by mixing 3-hydroxy-4-pentenoic acid and diethyl ether, sonicating, and obtaining a 3-hydroxy-4-pentenoic acid solution; mixing polyvinyl chloride, calcium carbonate and deionized water, sonicating, adding 2.8 to 3.2 times the mass of polyvinyl chloride in the 3-hydroxy-4-pentenoic acid solution, stirring at 58 to 62°C for 2 to 3 hours, filtering, washing with acetic acid, washing with deionized water, and vacuum drying for 24 to 26 hours.
7. The method for preparing a flame-retardant PVC film according to claim 6, characterized in that, The polyvinyl chloride mentioned is polyvinyl chloride of model SG-5.
8. The method for preparing a flame-retardant PVC film according to claim 2, characterized in that, The polyvinyl chloride film in step (3) is prepared by mixing ACR-Z30, modified polyvinyl chloride and modified silica, mixing them evenly in a high-speed mixer, placing them on a two-roll mill for two-roll milling at 168~172℃ for 4~6 minutes, hot pressing them on a flat vulcanizing machine at 178~182℃ for 7~9 minutes, and cold pressing them at room temperature for 4~6 minutes.
9. The method for preparing a flame-retardant PVC film according to claim 2, characterized in that, The surface treatment solution in step (3) is prepared by mixing polyethylene glycol methacrylate, ammonium persulfate and deionized water, and then sonicating.