Abstract
Abstract Micellar-templated silicas and organosilica-based materials from bis-silylated organosilica precursors with an ordered array of uniform mesopores are attractive for different applications. Since they are usually obtained in the form of fine powders, the material does not meet the criteria for many industrial uses or applications where good flow-through properties are required. Herein, a synthesis route is described where alginate hydrogel acts as form-giving matrix and can be subsequently removed leaving mechanically stable silica beads with 2 mm in diameter. In these beads post-synthetic micellar-templating is possible by so-called pseudomorphic transformation in alkaline surfactant solution, whereby a homogeneous mesophase is generated. Additionally, the formation of a second pore system of large mesopores occurs, so that bimodal porous silica beads are obtained. Following the same general concept, the synthesis of pure phenylene-bridged organosilica beads with likewise 2 mm in diameter was possible and again pseudomorphic transformation could be used to obtain mesoporous phenylene-bridged organosilica beads. The integrity of the organic bridge and the absence of alginate and the surfactant was proven by solid state NMR spectroscopy.
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have