Continuous Kinetics of Dextran Degradation

Abstract

Degradation of dextranes is studied in the framework of a first-order continuous kinetics. Here, the dextranes are approximately described by Schulz-Flory distributions, the parameters of which depend on the time. A new expression is introduced for the continuous rate function which is the continuous generalization of the rate constants of usual kinetics. One factor of this expression describes the scission probability in dependence on the molecular weight. The other factor describes the dependence on the location of the bond to be broken within the molecule. The rate function introduced is especially suitable if the bonds near the ends of a molecule are preferentially broken. The model is applied to four dextran samples degraded by acid hydrolysis. All experimental data may be described by a single set of three parameters.