Morphology and mechanical properties of polyamide/clay nanocomposites toughened with NBR/NBR-g-GMA: A comparative study

This work highlights the importance of nanoclay dispersion state in the nanocomposites containing polyamide 6 (PA6), nanoclay and elastomers as well as clay localization at the interface of thermoplastic/elastomer. Morphology and mechanical properties of a series of nanocomposites containing acrylonitrile butadiene rubber (NBR), glycidyl methacrylate-grafted NBR (NBR-g-GMA), and combined NBR/NBR-g-GMA were compared and discussed varying the concentration of nanoclay and elastomers. Better dispersion and stronger delamination of nanoclay layers was attained for samples comprising reactive NBR-g-GMA elastomer, as realized from a considerable increase in mechanical properties, which demonstrated on account of higher thermoplastic-elastomer interfacial adhesion. Aside from elastomer type, the presence of nanoclay was liable for the formation of thermodynamically less stable gamma crystals for PA6. Although impact strength of nanocomposites toughened with NBR-g-GMA was enhanced by nanoclay concentration, it followed an optimum by increasing elastomer content.