The Roles of Process Parameters on Structures and Mechanical Properties of Polypropylene/Clay Nanocomposites

Abstract

Process parameters are crucial to produce targeted qualities in polypropylene (PP)/clay nanocomposites, due to their roles on the generation of shear and diffusion. Thus, this research aims to observe their effects on structures and properties of PP/clay nanocomposites. Samples were produced by mixing PP, PP grafting maleic anhydride (PP-g-MA), and Cloisite 20A at fixed compositions, 88/9/3 wt%, respectively, in an internal mixer with variations on temperatures (210, 220, 230 °C) and speeds (60, 80, 100 rpm). Effect of mixing parameters on nanocomposite structures and properties were investigated from XRD, SEM and flexural properties. The results showed that all samples had intercalated as well as agglomerated structures. Further analysis on XRD and SEM showed that samples produced at high conditions (230 °C or 100 rpm) had similar structures. In contrast, low setting sample (210 °C and 60 rpm), despite its similarity on dispersion level, had longer agglomerates than that of mixed at high settings. Correlated both increase of d-spacing and agglomerates length to flexural properties suggested that modulus was more influenced by dispersion level, while strength was affected by agglomerates. However, it was worth to note that improvement on d-spacing, with availability of long agglomerates might not guarantee modulus and strength improvement due to low interfacial bonding.