Effect of process parameters on the polymer mediated synthesis of silica at neutral ph

We report herein the synthesis of well-defined silica structures at neutral pH and ambient conditions using poly(allylamine hydrochloride) (PAH), a cationically charged synthetic polymer, as a catalyst/template. Tetramethoxysilane (TMOS) was used as the precursor and the synthesis process parameters varied include TMOS pre-hydrolysis time (tP ), reaction time (tR), buffer, molecular weight of the polymer, TMOS concentration, polymer concentration and perturbation of the reaction mixture. It was found that the TMOS pre-hydrolysis time was an important parameter governing the resulting silica morphology along with the reaction time and the TMOS concentration. Characterization of the silica was performed using SEM, FTIR, EDS and XRD. The poly(allylamine hydrochloride), which was the catalyst/template, was found to be incorporated into the silica particles. These findings are of importance for understanding the role of polypeptides, in nature, and macromolecules, in general, that are capable of forming similar silica structures