Structure and mechanical properties of films of rigid‐rod polymers having flexible side chains

Abstract

AbstractA series of rigid‐rod polyesters with flexible alkoxy side chains of different length has been studied in order to determine the structure and properties of the polymers in various states (solid state, mesophase, melt). Various supermolecular structures can be obtained depending on the length of the side chains and on the preparation conditions of the samples. The relaxation behavior of the polymers has been investigated by dynamic mechanical measurements. Complex relaxation spectra have been observed, and types of molecular motions and structural rearrangements have been assigned to the observed mechanical relaxation transitions. The rheological behavior was studied in the mesophase and in the melt. In some polymers typical liquid‐crystalline properties have been observed, as for example the flow‐thinning effect. Large deformation of polymer films as well as the structure and mechanical strength of oriented samples have also been studied.