Synthesis and Adsorption Property of Poly(allylamine)-Silica Composite

Poly(allylamine)-silica composite(PAA-silica composite) was synthesized by grafting chloropropyltrichloro-silane(CPTCS- silica) gel onto PAA polymer in the solution. The PAA-silica composite with amino group content of 1.75 mmol/g was obtained by reacting 75 g CPTCS-silica with 185 g PAA-15 in 100 mL methanol. The result shows that PAA-silica composite could be used as an adsorbent for metal ions, which has an adsorption capacity of 0.85 mmol/g for Cu(Ⅱ) at pH=3.5 and of 0.53 mmol/g for Pb(Ⅱ) at pH=4.0 at 25 ℃, respectively. The structures and properties of silica gel, CPTCS-silica and PAA-silica composites were characterized by the FTIR spectra and angles of contact.