Fractal growth during early-stage spinodal decomposition in a hydrogen-bonded polymer blend

Small-angle neutron scattering has been used to study phase separation in a polymer blend made miscible by a dilute, random distribution of hydrogen bonds between the two components. In the one-phase region, scattering below a well-defined wave vector qc remains weak as the critical point is approached. During the early stages of spinodal decomposition, the formation of domains of a characteristic size R(t){≥}1/qc is apparent as a peak in the time-dependent structure factor, which scales as q^-2.40 independent of quench depth, raising interesting questions about the morphology of early-stage spinodal decomposition in these mixtures.