Size-controlled preparation of hollow silica spheres and glyphosate release
(1. Faculty of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang 212013, China;
2. College of Chemistry and Biology, Beihua University, Jilin 132013, China;
3. Chinese PLA 359 Hospital, Zhenjiang 212001, China)
2. College of Chemistry and Biology, Beihua University, Jilin 132013, China;
3. Chinese PLA 359 Hospital, Zhenjiang 212001, China)
Abstract: Different-sized hollow SiO2 spheres of 249-1348 nm in diameter were successfully prepared by using Na2SiO3 as the precursor and using polystyrene and polystyrene-methyl acrylic acid latexes as the templates. The diameter and shell thickness of the hollow SiO2 spheres increase with increasing the latex template diameter at a given mass ratio of SiO2 to latex template. The diameter and shell thickness of the hollow SiO2 spheres also increase with increasing the mass ratios of SiO2 to latex template. The presence of carboxylic acid groups on the surfaces of polystyrene-methyl acrylic acid latex templates favors the formation of dense and uniform SiO2 shells. The hollow SiO2 sphere is constructed by mesoporous shell with large specific surface area. When glyphosate is used as a release model chemical, glyphosate release rate is tuned by varying the shell thickness.
Key words: hollow SiO2 sphere; polystyrene; polystyrene-methyl acrylic acid; glyphosate release