Silicic acid polymerization catalyzed by amines and polyamines

Amines, particularly polyamines, catalyzed the polycondensation of silicic acid in water. The resultant gel contained these polyamines with a N/Si molar ratio of up to 0.5. IR and powder X-ray studies showed that silica gel and polyamines are hybridized at a molecular level through hydrogen bonding. The gel adsorbed anionic dyes from water, whereas normal silica gel adsorbs cationic dyes. Induced CD was observed for the indigo carmine adsorbed on silica gel-poly(L-lysine) hybrid, showing that the hybrid provides a chiral environment to the adsorbate.