Abstract: A composite polyvinyl alcohol (PVA) preservative film, a preparation method and an application thereof are provided. The film includes PVA of 9-12 parts, modified silicon dioxide nanoparticles of 2-5 parts, antimicrobial of 0.3-2 parts and deionized water of 100 parts. Fruits and vegetables sensitive to sunlight have lower requirements for illumination while preserving. With PVA as matrix and silicon dioxide (SiO2) nanoparticles as modified materials, composite PVA is obtained by controlling a particle size of SiO2 and modifying its surface. The composite PVA preservative film takes advantages of different refractive indexes between PVA and SiO2 and controlling the particle size of SiO2, thereby having a low luminous transmittance. The preservative film has an effect of light-proof on fruits and vegetables suitable for light-proof storage, and improves its gas transmission and water resistance because of adding SiO2, thereby facilitating packaging preservation of the fruits and vegetables.

Abstract: Disclosed are a method for preparing a high-strength anti-pollution anti-bacterial hollow fiber nano-filtration membrane and a product prepared by the method. The method comprises: S1, a chemical crosslinking reaction: placing an ultra-filtration base membrane in an acidic aqueous solution of glucose or an aqueous solution of phytic acid for a chemical crosslinking reaction to obtain a nano-filtration membrane; S2, a neutralization reaction immersing the nano-filtration membrane obtained in step S1 in an aqueous solution of alkali for the neutralization reaction, then washing the membrane to be neutral; S3, loading inorganic antibacterial agent: placing the membrane obtained in step S2 in an inorganic anti-bacterial agent solution for complexation, thereby obtaining a high-strength anti-pollution anti-bacterial hollow fiber nano-filtration membrane.

Abstract: Disclosed are a method for preparing a high-strength anti-pollution anti-bacterial hollow fiber nano-filtration membrane and a product prepared by the method. The method comprises: S1, a chemical crosslinking reaction: placing an ultra-filtration base membrane in an acidic aqueous solution of glucose or an aqueous solution of phytic acid for a chemical crosslinking reaction to obtain a nano-filtration membrane; S2, a neutralization reaction immersing the nano-filtration membrane obtained in step S1 in an aqueous solution of alkali for the neutralization reaction, then washing the membrane to be neutral; S3, loading inorganic antibacterial agent: placing the membrane obtained in step S2 in an inorganic anti-bacterial agent solution for complexation, thereby obtaining a high-strength anti-pollution anti-bacterial hollow fiber nano-filtration membrane.