▎ 摘　　要

NOVELTY - A nano-titanium dioxide composite UV-resistant degradable polyvinyl alcohol preservative film comprises 30-43 pts. wt. polyvinyl alcohol, 5-12 pts. wt. bentonite, 6-10 pts. wt. citric acid, 2-4 pts. wt. glycerol, 3-7 pts. wt. gluconic acid, 4-6 pts. wt. carbon black, 5-9 pts. wt. polyetheramine, 5-8 pts. wt. nano-silicon dioxide, sodium dodecylbenzenesulfonate, potassium hydroxide, graphene oxide, carbon nanotubes, pentanediol, acetic acid, nano-titanium dioxide, triethanolamine, KH550 (RTM: 3-aminopropyltriethoxysilane) ethanol, sulfuric acid and distilled water. USE - Nano-titanium dioxide composite UV-resistant degradable polyvinyl alcohol preservative film. ADVANTAGE - The nano-titanium dioxide composite UV-resistant degradable polyvinyl alcohol preservative film has improved tensile strength and water resistance. DETAILED DESCRIPTION - A nano-titanium dioxide composite UV-resistant degradable polyvinyl alcohol preservative film comprises 30-43 pts. wt. polyvinyl alcohol, 5-12 pts. wt. bentonite, 6-10 pts. wt. citric acid, 2-4 pts. wt. glycerol, 3-7 pts. wt. gluconic acid, 4-6 pts. wt. carbon black, 5-9 pts. wt. polyetheramine, 5-8 pts. wt. nano-silicon dioxide, 2-5 pts. wt. sodium dodecylbenzenesulfonate, 3-6 pts. wt. potassium hydroxide, 4-7 pts. wt. graphene oxide, 7-10 pts. wt. carbon nanotubes, 4-6 pts. wt. pentanediol, 3-5 pts. wt. acetic acid, 4-8 pts. wt. nano-titanium dioxide, 3-7 pts. wt. triethanolamine, 2-6 pts. wt. KH550 (RTM: 3-aminopropyltriethoxysilane), ethanol, sulfuric acid and distilled water. An INDEPENDENT CLAIM is included for preparation method of nano-titanium dioxide composite UV-resistant degradable polyvinyl alcohol preservative film, which involves (a) mixing bentonite and glycerol, adding distilled water in a ratio of 1:(10-20), uniformly stirring and dispersing for 1-2 hours, regulating the pH value to 7-8, adding citric acid and ethanol in a ratio of 1:(5-10), heating at 70-80 degrees C in a constant temperature water bath, dripping gluconic acid, stirring and reacting for 3-4 hours, filtering, water washing and alcohol washing 3-5 times, vacuum drying and crushing at 30-50 degrees C, and passing through 100-200 sieve, (b) adding sulfuric acid to carbon black in a ratio of 1:(3-5), magnetically stirring for 1-2 hours, and ultrasonically processing at 70-80 degrees C for 2-3 hours to obtain solution (A), dispersing polyetheramine and nano-silicon dioxide in a ratio of 1:(10-20) in distilled water, adding to the solution (A), magnetically stirring for 4-8 hours, and drying at 60-70 degrees C, (c) dissolving sodium dodecylbenzenesulfonate and potassium hydroxide in distilled water in a ratio of 1:(15 -25), adding carbon nanotubes and graphene oxide, increasing the temperature to 85-95 degrees C, ultrasonically vibrating for 4-5 hours, filtering, washing with water 3-5 times, and vacuum drying at 50-60 degrees C, (d) heating nano-titanium dioxide at 70-80 degrees C for 5-8 hours, adding distilled water in a ratio of 1:(20-30), stirring and dispersing, adding triethanolamine, adding KH550 (RTM: 3-aminopropyltriethoxysilane) and ethanol in a ratio of 1:(5-10), increasing the temperature to 75-85 degrees C, regulating the pH value to 8-9, ultrasonically reacting for 1-2 hours, centrifuging, and completely drying at 80-90 degrees C to obtain modified powder, (e) adding distilled water to polyvinyl alcohol in a ratio of 1:(20-30), heating at 80-90 degrees C, stirring and dissolving, adding the materials obtained in the steps (a), (b), (c) and (d), pentanediol and acetic acid, fully mixing, ultrasonically processing for 1-2 hours, stirring at constant temperature to react for 1-2 hours, removing bubbles, cooling to room temperature, pouring on an organic glass plate, coating with a film, leaving still the film at room temperature for 6-10 hours, volatilizing the moisture, and drying the film in a vacuum drying box at 45-55 degrees C for 5-10 hours.