Synthesis and characterization of soluble conjugated poly(p- phenylenevinylene) derivatives constituted of alternating pyrazole and 1,3,4-oxadiazole moieties

New soluble poly(p-phenylenevinylene) derivatives with 1,3,4-oxadiazole and pyrazole rings along the main chain were synthesized by Heck coupling. The new conjugated polymers are soluble in common organic solvents as a result of the fully conjugated backbone with dodecyloxy side groups. The polymers show relatively high glass-transition temperatures (up to 160C) and good satisfactory thermal stability. Solutions of the polymers emit blue-greenish light with photoluminescence (PL) emission maxima around 490500 nm. The PL spectrum of the polymer's thin films, with a maximum at 515 nm, shows a red-shift (∼20 nm), with respect to the solution spectrum. Cyclic voltammetry reveals that both conjugated polymers have reversible oxidation and irreversible reduction, making them n-type electroluminescent materials. The electron affinity of the new polymers was estimated as 2.732.74 eV. The weight-average molecular weights (M _w) of the new soluble polymers were in the range of 47904950.