화학공학소재연구정보센터
Langmuir, Vol.30, No.2, 584-591, 2014
Layer-by-Layer Synthesis of Mechanically Robust Solvent-Permeable Silica Nanoshells
w/w A layer-by-layer (LbL) synthesis of mechanically robust micrometer-diameter nanoshell silica was developed. Silica was templated onto polstyrene latex particles using a modified Stober synthesis. Each subsequent silica layer was deposited after adsorbing cationic polymer poly(allylamine) hydrochloride. The silica shell grew approximately 30 nm for each reaction step. The polystyrene-silica-core-shell particles were calcined at 500 degrees C to remove the latex core. The synthesis was adapted to nonspherical shapes using anisotropic polystyrene dicolloids as templates. The silica nanoshells were functionalized to render them organophilic or fluorescent. The rates at which water, ethanol, and aqueous sucrose solution (60% w/w) permeate the silica shells were compared using spectrophotometry and conductivity measurements. The rate of solvent uptake ranged between under 1 h to over 1 week depending on the surface chemistry of the nanoshells.