Rheological study of the gelation kinetics of a concentrated latex suspension in the presence of nonadsorbing polymer chains

The gelation kinetics of a concentrated latex suspension in the presence of two nonadsorbing sodium carboxymethylcellulose polymer chains with differe nt molecular weight has been investigated. The experimental results indicat e that the presence of the polymer chains generates two concomitant and opp osite effects on the gelation time. Providing excluded volume effects are p redominant, the gelation time was found to decrease. When a critical value of the polymer volume fraction in the bulk phase was reached, the gelation time increased with concentration due to viscosity effects. Moreover, the d ynamic rheological measurements were shown to exhibit the influence of the excluded volume effects on the fractal dimension of the growing aggregates of the gelified networks.