POLYMERIC AMINES: ROLE IN BIOSILICIFICATON AND POTENTIAL IN NANOTECHNOLOGIES

摘要

Condensation of silicic acid was studied in the presence of poly(vinylamine) fractions (238-11000 units). The reaction results in soluble nanoparticles or composite precipitates depending on polymerization degree of the organic polymer and pH. The structure of the nanoparticles in solution was close to a microgel for high-molecular weight polymers or to hyper-branched systems when the extent of polymerization was below 1000. Silicic acid exists in these particles in slightly polymerized form in contrast to silica obtained without polymers. We consider polymer - poly(silicic acid) nanoparticles as a new silica precursor for the design of silica and composite materials. We suspect that a similar method of storing silicic acid in an active state is used in silicifying organisms, at least in diatom algae.