A dielectric study on the local dynamics of miscible polymer blends: poly(2-chlorostyrene)/poly(vinyl methyl ether)

Dielectric relaxation of poly(vinyl methyl ether) (PVME)/poly(2-chlorostyrene) (P2CS) blends with a lower critical solution temperature (LCST) was investigated in the one-phase region over a wide range of temperature. Four distinct dielectrically active processes were observed and identified as α1, α2, β and γ relaxation processes. It was found that the β and γ processes were almost unaffected upon varying the blend composition, while their relaxation intensities were approximately proportional to the PVME content. Furthermore, there exist two peaks (α1, α2) corresponding to the segmental relaxation process of each component. By comparing this with the data obtained by small-angle X-ray scattering and differential scanning calorimetry, the experimental results are discussed in terms of dynamical heterogeneity of miscible polymer blends composed of two polymer components with a large difference in glass transition temperatures.