Fabrication Of Nano Zinc Oxide By Sonochemical Method And Its Research In The Polyacrylate Emulsion

Nano Zn O has attracted considerable attention due to its lower density,abundant morphology and high specific surface area.Polyacrylate emulsion possess wide application prospect in the field of leather finishing on account of their excellent comprehensive properties.However,the poor hygienic performances of dense polyacrylate coating affect significantly the wearing comfort for leather.Therefore,based on the excellent physical and chemical properties of nano ZnO as the research object,sonochemical synthesis and characterization of nano ZnO with the particular morphology were carried out.Besides,polyacrylate/nano ZnO composite emulsion was procured by physical blending of nano ZnO with different morphologies and polyacrylate emulsion.The fabricating conditions of nano ZnO were optimized with water vapor permeability,water resistance,mechanical properties,ultraviolet shielding and yellowing resistance of composite films as indexes.Eventually,the polyacrylate/nano ZnO composite emulsion were applied in leather finishing process,the main contents are listed as follows.The diameter and cavity size of hollow sphere-like ZnO were 350 nm and160 nm,differentiately.The result of BET revealed the existence of abundant mesoporous structures in hollow sphere-like ZnO.The specific surface area,pore volume and average pore size of hollow sphere-like Zn O were 11.11 m²/g,0.04cm³/g and 16.75 nm,differentiately.When the solvents volume ratio was 1:8:1 of ethylene glycol/DMSO/H₂O,the reaction pH was 8,and ultrasonic power was400 W,the morphology of hollow sphere-like ZnO and the properties of polyacrylate/hollow sphere-like ZnO composite film were best.Compared with polyacrylate film,the water vapor permeability,water resistance,tensile strength and yellowing resistance of polyacrylate/hollow sphere-like ZnO composite film increased by 23.99%,48.06%,57.16%and 96.53%,severally.The size of flower-like ZnO were 1.2?m.The width and length of a single ellipsoid-like“petals”was about 300 nm and 600 nm,differentiately.The result of BET revealed the existence of abundant mesoporous structures in flower-like Zn O.The specific surface area,pore volume and average pore size of flower-like Zn O were 14.65 m²/g,0.07 cm³/g and 20.27 nm,differentiately.When the alkali source was ammonia water,the reaction p H was 8,the ultrasonic time was 30min,and the water content was 50%,the morphology of flower-like ZnO and the properties of polyacrylate/flower-like ZnO composite film were best.Compared with polyacrylate film,the water vapor permeability,water resistance,tensile strength and yellowing resistance of polyacrylate/flower-like ZnO composite film increased by 52.91%,53.13%,58.85%and 98.25%,severally.The size of hollow flower-like Zn O were 500 nm.A single"petals"exhibited significant cavity architecture.The result of BET revealed the existence of abundant mesoporous structures in hollow flower-like ZnO.The specific surface area,pore volume and average pore size of hollow flower-like Zn O were 16.01 m²/g,0.03 cm³/g and 10.94 nm,differentiately.When the zinc source was zinc acetate dehydrate,the ultrasonic frequency was 45 KHz,the water content was 75%,and dosage of citric acid was 5 mmol,the morphology of hollow flower-like ZnO and the properties of polyacrylate/hollow flower-like Zn O composite film were best.Compared with polyacrylate film,the water vapor permeability,water resistance,tensile strength and yellowing resistance of polyacrylate/hollow flower-like ZnO composite film increased by 64.25%,53.21%,110.18%and 101.49%,severally.The enhancement effect of polyacrylate/nano ZnO composite film is closely related to the specific surface area of nano ZnO.The hollow flower-like Zn O is combined with the roughness of the flower-like ZnO and cavity of the hollow sphere-like ZnO,which has the largest specific surface area,while hollow sphere-like Zn O is the minimum.Therefore,the comprehensive properties of three composite emulsions and their application in leather finishing were that polyacrylate/hollow flower-like ZnO composite emulsion is the best,while polyacrylate/hollow sphere-like ZnO composite emulsion is the worst.