The role of liquid-crystalline polymer rheology on the evolving morphology of immiscible blends containing liquid-crystalline polymers

A new method is demonstrated that applies the Pored limit of small angle neutron scattering to measure the interface morphology in concentrated, immiscible blends in situ under simple shear. The effect of viscoelastic contrast on rheology and blend microstructure is probed for a model dispersion of liquid crystalline polymer dispersed in a linear polymer matrix. Comparison to theories demonstrates the complex morphology evolution is a consequence of the unique rheology of liquid crystalline polymers. The results at low shear rates are used to predict the onset of stable microfibrillation at higher sheer rates through consideration of the contrast in first normal stress differences. (C) 1999 The Society of Rheology. [S0148-6055(99)00703-8].