Melt processing and characterization of multicomponent polymeric nanocomposites containing organoclay

Abstract Nylon 6 (Ny)/polypropylene (PP)/maleated polypropylene (PP‐g‐MA)/organoclay/wollastonite composites were prepared by melt processing. The polymers' composition was kept constant ([70PP/30Ny]/4PP‐g‐MA). Melt compounding was conducted using a twin‐screw extruder in three different methods: (1) simultaneous incorporation of the components into the compounding equipment, (2) preparation of [Ny6/clay] concentrate, and then in a second step, mixing the other components with the concentrate, and (3) mixing of PP with wollastonite and clay followed by the addition of Ny6 and PP‐g‐MA in the second step. Injection‐molded specimens were characterized in tension, scanning electron microscopy, X‐ray diffraction (XRD), and differential scanning calorimetry. The sequence of component addition greatly influences the structure and properties of the composites. Enhanced mechanical properties were achieved when the two‐step mixing procedure was used for the PP/Ny6/PP‐g‐MA/clay system (method 2) and also for the PP/Ny6/PP‐g‐MA/clay/wollastonite system (method 3). The XRD pattern of the PP/Ny6/PP‐g‐MA/clay nanocomposites produced by the two‐step mixing method does not show a characteristic basal reflection of the pristine organoclay, indicating a predominately exfoliated structure of clay. POLYM. COMPOS., 28:417–424, 2007. © 2007 Society of Plastics Engineers