THEORY OF LINEAR VISCOELASTICITY FOR SINGLE-PHASE NEMATIC MIXTURES

A macroscopic model for incompressible homogeneous (single phase) bina ry nematic mixtures under isothermal conditions is given; the model is restricted to two miscible nematic liquid crystals. The rheological m odel is a generalization of the standard Ericksen's nematorheological model for single component uniaxial rod-like nematic liquid crystals. The theory is used to characterize the linear viscoelasticity of the n ematic mixture when subjected to small amplitude oscillatory shear. Mi xture elasticity is shown to predict a frequency dependence of the dyn amic viscosity (eta' and eta '') essentially identical to those obtain ed using Frank elasticity and molecular elasticity. The composition de pendence of the storage G' and loss modulus G '' is found to be nonlin ear, and stronger at low frequency than at high frequency.