One of the most common methods to access thioamides is reacting amides with Lawesson's reagent (LR). Even though the use of LR is well established in organic chemistry, it has been not popular with polymer chemists, probably due to difficulties in removal of the reaction's byproducts. There are a few studies performed on modification of diketopyrrolopyrrole polymers with LR to obtain dithioketopyrrolopyrrole-based polymers for enhancing their electrical conductivity and modifying optical properties. Hifumi et al. reported on poly(arylene ether phosphine sulfide) polymers obtained via thionation of poly(arylene ether phosphine oxide)s with LR which exhibit increased glass transition temperatures. Polyamides have also been modified