A rapid and green synthesis of poly(p-dioxanone) (PPDO)/montmorillonite (MMT) nanocomposites was carried out smoothly and effectively nder constant microwave powers of 30, 60, 90, and 120 W in a microwave oven at a frequency of 2.45 GHz. The temperature of polymerization was in the range 103-224 degrees C. PPDO, with a viscosity-average molecular weight of 111,000 g/mol and a conversion of 85%, was obtained at 60 W for 10 min, in which the ratio of p-dioxanone to AlEt3 was 300/1 (mol/mol). The intercalated structure of PPDO/MMT nanocomposites was confirmed by X-ray diffraction and transmission electron microscopy. Thermogravimetry data showed that the thermal stability of the nanocomposites prepared under microwave irradiation was improved with respect to those prepared via conventional heating. (C) 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012