The present study reports for the first time the preparation of poly(2-ethyl-2-oxazoline)/clay nanocomposites. The tosyl-functionalized montmorillonite clay is utilized as initiator for the living cationic ring-opening polymerization of 2-ethyl-2-oxazoline, which triggers the delamination of silicate layers in the polymer matrix and leading to nanocomposite formation. The living nature of the polymerization has been confirmed by kinetic studies. The morphology and thermal properties of nanocomposite have been evaluated using X-ray diffraction, transmission electron microscopy, differential scanning calorimeter and thermogravimetric analysis. All nanocomposite samples have a mixed exfoliated/ intercalated silicate layers and an improved thermal stability compared to pure poly(2-ethyl-2-oxazoline). (C) 2016 Elsevier Ltd. All rights reserved.