Equilibrium aspects of polycation adsorption on silica surface: How the adsorbed layer responds to changes in bulk solution
Adsorption of cationic high molecular weight polyacrylamides (CPAM) (M-w is about 800 kDa) with different fractions of cationic units tau = 0.09 and tau = 0.018 onto silica surface was studied over a wide range of pH (4-9) and KCl concentration (c(s) = 10(-3)-10(-1) M) by in-situ null ellipsometry. We discuss how the adsorbed layer depends on the bulk conditions as well as kinetically responds to