RDF INVESTIGATIONS ON CONCENTRATED-SOLUTIONS OF POLY(PARA-PHENYLENE-1,3,4-OXADIAZOLE) IN SULFURIC-ACID

Reduced radial distribution functions (RDFs) for non-crystalline solutions of poly(p-phenylene-1,3,4-oxadiazole) (POD) in H2SO4 have been determined and discussed for the first time. In solutions of up to 14 wt% POD in H2SO4 the POD monomeric units act as simple perturbations of the correlation lattice of the pure solvent. Between 14 and 15 wt% POD content a phase transition from isotropic solution to crystal solvates and H2SO4 occurs. The short range interactions of POD molecules with the correlation lattice of a 96.2 wt% aqueous H2SO4 solvent are considerably stronger than for the same POD content in a 100% H2SO4 solvent.