Abstract
Sidechain-type liquid crystalline polysiloxane(SLCSs) diluted with polydimethylsiloxane(DMS) show a large increase in viscosity upon application of an electric field. We have investigated the solvent effect upon the ER behavior. When the weight fraction of DMS in smaller than 10%, the shear stress of the mixture of SLCS and DMS is nearly constant and the increase in the shear stress by the implication of an electric field is very small. With increasing the DMS's weight fraction, the zero-field shear stress drastically falls to generate a large contrast between the shear stresses with and without an applied electric field. ER effect of a SLCS employing phenyl substituted DMS as a solvent is smaller than that employing DMS. The ER effect of the SLCS decreases with increasing the phenyl content of phenyl substituted DMS. These results suggest that the phase separation between the SLCS and solvent is responsible for the generation of ER effect.
