Morphology resulting from coupling of phase separation and glass transition in polymer blends

At temperatures near glass transition temperature, off-critical binary polystyrene/polybutadiene (PS/PB) mixtures were found to experience phase separation through the mechanism of slow hydrodynamic coarsening. A bicontinuous phase structure was produced on quenching the PS/PB-blends under cloud point curve. Different coarsening regimes of this percolation structure depending on degrees of supersaturation were found. At late stages of coarsening, secondary phase separation was observed.