Melt compounding is one of the most used methods to produce thermoplastic-based nanocomposites. The aim of this study is the assessment of the effects of processing set-up and conditions on the structure and properties of low-density polyethylene/organically modifies layered silicate (OMLS) nanocomposites obtained by a two-step process by concentrate masterbatch route. Concentrate masterbatch formulation and dilution have been investigated to correlate processing parameters with final nanocomposites structure by means of morphological and physical characterization. Even if a good dispersion/intercalation occurred regarding concentrate masterbatch, the probability of a further OMLS dispersion during the masterbatch dilution process depends remarkably on the extruder mixing capacity, with important consequences for the industrial application of masterbatch technology in net shape forming processes. POLYM. ENG. SCI., 2013. (c) 2012 Society of Plastics Engineers