Effect of shear on phase-separation in polystyrene/poly(vinyl methyl ether)/ organoclay nanocomposites.

Blends of polystyrene (PS)/poly(vinyl methyl ether) (PVME) modified with two types of organoclay were prepared by solution casting from toluene. The effect of clay addition on the phase separating morphology of PS/PVME blend with critical composition (25/75) was examined both under quiescent conditions and under shear flow. The variation in critical temperature of phase separation was assessed by rheology, small angle laser light scattering (SALLS) and by on-line laser light transmission during shearing at fixed shear rate during heating. Transmission electron microscopy and X-ray diffraction analyses were used to examine the state of delamination and distribution of clay nanoparticles with the blend matrix.