MELT DIFFUSION IN LIQUID CRYSTALLINE POLYMERS RIGID ROD VS. SEMI - RIGID MODEL SYSTEMS

摘要

Melt diffusion coefficients for a rigid thermotropic liquid crystalline polymer (RR) are measured as a function of temperature. The Arrhenius behavior of the diffusion coefficient, D~*, observed for the polyester, RR, contrasts greatly with the more complex behavior observed for D~* in polyether systems. The presence of transesterification in RR is one explanation for the difference in behavior. Yet, when possible diffusion rates based only on transesterification are estimated, transesterification as the sole explanation is called into question. Alternative possibilities for the behavior are considered.