| Abstract: | Polypropylene‐layered silicate nanocomposites consisting of three components—pure polypropylene, maleated polypropylene, and organically modified silicate—were prepared by the melt‐intercalation method to investigate melt‐extensional properties such as melt strength, neck‐in test, and orientation behavior. The nanocomposites showed an enhanced tensile modulus, enhanced storage modulus, much enhanced melt tension, and reduced neck‐in during the melt processing as compared with neat polymer. The uniaxial drawing induced the silicate surface to align parallel to the sheet surface. The c and a* axes of the polypropylene crystals were bimodally oriented to the flow direction, and the b axes were oriented to the thickness direction. The bimodal orientation of the polypropylene crystal was enhanced with the concentration of silicates. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 158–167, 2005 |
