Rate equation of gelation of chromium(III)-polyacrylamide sol

During gelation, the time dependence of the apparent viscosity has been used to analyze the kinetics of the gelation of polyacrylamide (PA) sol with chromium (III) ions. The investigations have stablished the following facts: Before gelation the relation between the viscosity, η, of Cr(III)-PA sol and the PA concentration is η = f([PA]) = 2.36×1015 [PA]3.15 and the rate equation of gelation in the steady-state stage during gelation is expressed as Vn = ks f([PA]) [PA]2 [Cr(III)]2.