Mechanical properties of polypropylene composites reinforced by organoclays and glass fibers

In this study, isotactic-polypropylene (iPP) composites reinforced with an organoclay were prepared by a twin-screw extruder by blending iPP with clay that modified with an amine surfactant. The use of surfactant caused the layered silicate of organoclay in iPP/organoclay nanocomposites to move further apart. After that iPP/organoclay nanocomposites were then blended with iPP that had been reinforced with glass fibers using the twin-screw extruder in various blend ratios. The iPP/glass fibers /organoclay nanocomposites were then characterized for their morphology and various properties, thermal and mechanical integrity. X-ray diffraction (XRD) analysis indicated that the silicate layers of the organoclay in the nanocomposites were more ordered than those of the original organoclay, which was confirmed by transmission electron microscopy (TEM). The iPP/organoclay nanocomposites showed greater content of β-crystalline phase, increased degree of crystallinity, and increased crystallization temperature than the iPP/glass fibers composites, which was confirmed by both XRD and differential scanning calorimetry (DSC) results. With regards to the mechanical properties, iPP/organoclay nanocomposites exhibited lower stiffness than iPP/glass fibers composites. Interestingly, the iPP/glass fibers/organoclay nanocomposites exhibited much improved stiffness than both of the iPP/organoclay nanocomposites and the iPP/glass fibers composites.