Processing and Properties of Nanocomposites Based on Layered Silicate and Carboxylated Nitrile Rubber

Abstract

Nanocomposites based on carboxylated nitrile rubber (XNBR) and organomodified clay were prepared under different mixing conditions. At higher mixing temperatures, a mixed intercalated/exfoliated morphology was obtained as evidenced by X-ray diffraction studies and transmission electron microscopy. A remarkable improvement of physical properties was achieved when the layered silicates were mixed at high temperatures. The presence of carboxylic group in the rubber improves the interaction and exfoliation process which can be shown by IR studies. With the increase of the organoclay loading and processing temperature, a considerable effect on dynamic properties was found during strain sweep analysis which was explained by ‘Payne’-like effects. Finally, a mechanism of the layered silicate dispersion in carboxylated nitrile rubber has been proposed.