Finite impurity size effects on heterogeneous nucleation occurring in diblock copolymers

Abstract

The role played by heterogeneous nucleation in phase transformations occurring in asymmetric, diblock styrene-butadiene is examined using the experimental technique of time-resolved small-angle x-ray scattering. Transient nucleation effects are clearly identifiable through comparison of the early time transformation kinetics seen with samples containing varying impurity sizes. These results are interpreted in the context of a simple model of transient nucleation rate incorporated into classical theories of isothermal transformation kinetics.