Morphology and properties of nanocomposites from organoclays with reduced cation exchange capacity

Organoclays with different levels of reduction in the original cation exchange capacity (CEC) were prepared to characterize the morphology and Young's modulus of their melt-processed nanocomposites made from nylon 6 (PA-6) and polypropylene/polypropylene grafted with maleic anhydride (PP/PP-g-MA). Wide-angle X-ray scattering (WAXS), transmission electron microscopy (TEM), and Young's modulus data are reported. Three different levels of CEC reduction were obtained; WAXS analysis and percentage loss on ignition (LOI) calculations for these organoclays showed a reduction in both the intergallery spacing and in the amount of organic modifier contained in the clay with CEC reduction. The morphology and modulus results show that these reduced-CEC organoclays led to lower exfoliation and modulus enhancement for both PA-6 and PP/PP-g-MA nanocomposites. The results may be influenced by differences in layer charge and charge distribution that could have been produced during the charge reduction process. (C) 2007 Wiley Periodicals, Inc.