Simultaneous polypropylene functionalization and nanoclay dispersion in PP/Clay nanocomposites using ultrasound

ABSTRACT Polypropylene nanocomposite materials were prepared with 5 and 10 wt % cloisite C20A clay, jointly with 0.6 and 1.2 wt % of maleic anhydride (MA) for the simultaneous polymer functionalization and clay dispersion in a twin screw extruder assisted with ultrasonic irradiation, using different sonication intensities (231, 347, and 462 W, which correspond to 30%, 45%, and 60% of the maximum instrument intensity, “770 W”) all in a single‐step operation. The MA polymer functionalization was followed by FTIR spectroscopy and determined by titration. The increase in modulus of the obtained PP/Clay nanocomposites was attributed to the greater dispersion level, presumably achieved becuase of the joint application of the PP–Clay compatibilization with MA and the sonication during processing in a twin screw extruder. The greater level of clay dispersion was verified by the displacement of the XRD diffraction peak to lower angles, indicating an intercalated‐exfoliated structure that was corroborated by STEM. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40631.