Dynamic soft elasticity in monodomain nematic elastomers

Abstract: We study the linear dynamic-mechanical response of monodomain nematic liquid crystalline elastomers under shear in the geometry that allows the director rotation. The aspects of time-temperature superposition are discussed at some length and Master Curves are obtained between the glassy state and the nematic transition temperature Tni. However, the time-temperature superposition did not work through the clearing point Tni, due to the transition from the “soft-elasticity” nematic regime to the ordinary isotropic rubber response. We focus on the low-frequency region of the Master Curves and establish the power law dependence of the modulus G' ∝ ωa. This law agrees very well with the results of static stress relaxation, where each relaxation curve obeys the analogous power law G' ∝ t-a in the corresponding region of long times and temperatures.