Kinetics of thermal polymerization of shellac. V. Turbidimetric and fractionation studies



In the present investigation, the changes in precipitation of the shellac condensates with curing time have been followed turbidimetrically. The experimental data support the saturation limit law. Further, the fractionation of a polymer with low degree of polymerization has been effected by the integral method, and the relation between Wx (the weight fraction of the precipitate) and v (the volume of precipitant added) has been established. In addition, the fractions have been characterized in terms of inherent viscosity. The experimental data, which exhibit alternation behavior, have been confirmed by a number of statistical tests.