Short-Range-Order Effects in the Isotropic Phase of a Side-Chain Polymeric Liquid Crystal

Short-range-order effects in the isotropic phase of a side-chain polymeric liquid crystal are studied by means of electric and acoustic birefringences and the viscosity. The static properties are comparable to those of conventional liquid crystals, but the dynamic properties show quite different behavior, characterized by a relaxation time which diverges as ${(T-T_c^{*})}^{-1.55\mathrm{}}$, rather than ${(T-T_c^{*})}^{-1\mathrm{}}$, $T_c^{*}$ being a virtual second-order transition temperature. Analysis of the results according to the de Gennes theory enabled the friction coefficients of this theory to be established.