氧化锌为模板制备中空二氧化硅微球及其对聚丙烯酸酯薄膜性能的影响

Fabrication of Hollow Silica Microsphere Using Zinc Oxide as Template and Its Effect on Polyacrylate Film Properties

以氧化锌为模板,在超声作用及表面活性剂的辅助作用下正硅酸乙酯原位水解制备核/壳型氧化锌/二氧化硅复合微球,然后在盐酸溶液中溶解氧化锌核制备中空二氧化硅微球,采用红外光谱仪(FTIR)和透射扫描电子显微镜(TEM)表征其结构和形貌。最后,将中空二氧化硅微球应用于聚丙烯酸酯薄膜中考察其透水汽性和力学性能。结果表明,采用Tween-80和聚乙烯吡咯烷酮为表面活性剂可有效分散氧化锌,且有利于二氧化硅包覆在其表面,从而成功获得核/壳型氧化锌/二氧化硅复合微球。同时,采用盐酸作为刻蚀剂,在pH=2.0的条件下,可有效刻蚀氧化锌,获得中空二氧化硅微球。FTIR表明形成了中空二氧化硅,中空二氧化硅微球的壳层内部附有一层未被刻蚀的氧化锌。TEM表明,该中空二氧化硅微球粒径为47nm左右,其壳层厚度为12nm,空腔直径为23nm。将制备的中空二氧化硅微球引入到聚丙烯酸酯薄膜中,该中空二氧化硅微球可显著改善聚丙烯酸酯薄膜的透水汽性能和力学性能。当中空二氧化硅微球的质量分数为1.5%时,聚丙烯酸酯薄膜的透水汽性能达到最佳。

Mono-dispersed zinc oxide/silica core/shell microsphere was prepared by uitrasound/surfactant- assisted template method with zinc oxide as a template and tetraethoxysilane as a silicon source. The zinc oxide/silica core/shell microspheres were treated with hydrochloric acid to etch the core of zinc oxide and obtain the hollow silica microsphere. The structure and morphology of hollow silica rnicrosphere were characterized by Fourier transform infrared spectroscopy （FT-IR） and transmission electron microscopy （TEM）, re- spectively. The hollow silica microspheres were used for a polyacrylate film. The effect of hollow silica mierospheres on the water-vapor permeability and mechanical properties of the polyacrylate film was investigated. The results show that Tween-80 and polyvinyl pyrroli- done can be used for the dispersion of zinc oxide and the cover of silica. The zinc oxide/silica core/shell microsphere was formed. Hy- drochloric acid is effective in etching the zinc oxide core of zinc oxide/silica core/shell microsphere when pH=2 to obtain the hollow sil- ica microsphere. The FT-IR results show that the inner surface of the shell of hollow silica microsphere contains some zinc oxide. The TEM re.suits show that the particle size of the hollow silica mierospheres is 47 nm, the thickness of silica shell is 12 nm and the diameter of hollow cavity is 23 nm The introduction of hollow silica sphere can improve the water-vapor permeability and mechanical properties of polyacrylate film. The optimum water-vapor permeability of polyacrylate film can be obtained when the dosage of hollow silica micro- spheres is 1.5wt%.