Preparation of polypropylene nanocomposites by melt-mixing: Comparison between three organoclays

Polypropylene (PP)-based nanocomposites reinforced with three different organoclays (Dellite((c)) 67 G, Cloisite((c)) 20, and Cloisite((c)) 30B) were prepared via melt-mixing in an internal mixer. The three organoclays differ essentially via their organic modifier and interlamellar distance. The nanocomposites microstructure was characterized at different scales through scanning electron microscopy (SEM) observations, X-ray diffractometry, and rheological measurements. The influence of processing parameters such as rotor speed and mixing time was quantified. The results show that Dellite((c)) 67 G and Cloisite((c)) 20 present a good dispersion state, with an intercalation of the tactoids by the polymer chains and a good level of exfoliation. In contrast, whatever the processing conditions, Cloisite((c)) 30B was not dispersed correctly in the matrix, showing neither intercalation nor exfoliation, even in the presence of compatibilizer. (c) 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45053.