LATTICE MODEL OF HETEROGENEOUS POLYMER-CHAINS IN THE LIQUID-CRYSTALLINE STATE .2. LOCAL RELAXATION PROPERTIES

Using a lattice description, the short- and medium-scale dynamics of the heterogeneous model of main-chain liquid-crystalline polymers have been considered. Chain mobility is assumed to occur by means of three- and four-bond kinetic-unit jumps. Mobility and force coefficient tensors, and linear relaxation equations for the average projections of chain bonds have been obtained. Both acoustic and optical branches of the relaxation spectrum are shown to be split into longitudinal and transverse components. A pronounced dependence of relaxation spectrum shape and splitting magnitude on the spacer length has been found.