Abstract Intrinsically soluble terpolymers with alternating conjugated chromophoric units with inert hexane-1,6-dioxy units were synthesized using the Wittig reaction. The terpolymers were characterized with FTIR, 1H NMR, UV–vis and fluorescence techniques. The thermal properties were investigated with DSC and TGA under nitrogen atmosphere. The photoluminescence of the terpolymer films was found to have emissive region and emission maxima, λ em, similar to that of poly(2,5-dimethoxy-1,4-phenylenevinylene) films prepared via the Wessling method. A forward bias current was obtained and the devices showed typical diode behaviour. The photodegradation of the terpolymer films was studied by applying low-intensity irradiation at a fixed wavelength to the film.