ABSTRACT
Polyolen/nanoller composites are in demand for many applications, including aerospace and automotive parts, tires, packaging, as well as electronic devices.1-3 The most common polyolens are polyethylene (PE), polypropylene (PP), and ethylene-propylenediene terpolymer (EPDM). Filler materials include clay minerals, carbon nanotubes, bers, and metal oxides. The structure of nanoscale llers can be broadly categorized into 2D layers, 1D tubes, and 3D particles according to shape and aspect ratio.3 In contrast to micrometer-size llers, nanoscale llers improve mechanical, optical, and catalytic properties of polyolen nanocomposites with a much smaller amount of loading. The diversication of properties of neat polyolens by nanoscale llers depends signicantly on interfacial features such as surface modication and the associated degree of dispersion within the polymer matrix. Therefore, a large ratio between interfacial area and volume of the ller material, a comparable dimension of the llers and of the polymer chains, as well as short particle-particle spacing in comparison to microscale and macroscale composites
CONTENTS
7.1 Overview of Inorganic Fillers and Theoretical Approaches ....................................... 205 7.1.1 Inorganic Fillers and Interfacial Properties ....................................................... 205 7.1.2 Theoretical and Computational Methods .......................................................... 207
7.2 Modication of Layered Silicates and Interfacial Properties in Polyolen Nanocomposites ................................................................................................................. 209 7.2.1 Thermodynamic Model for Dispersion .............................................................. 209 7.2.2 Structure of Organically Modied Layered Silicates ....................................... 210 7.2.3 Cleavage Energy and Potential for Exfoliation .................................................. 212
7.3 Modication of Carbon Nanotubes and Interfacial Properties in Polyolen Nanocomposites ................................................................................................................. 215
7.4 Modication of Spherical Particles and Interfacial Properties in Polyolen Nanocomposites ................................................................................................................. 219
References ..................................................................................................................................... 220
are desirable. The ratio of interfacial area to volume of various ller materials as a function of aspect ratio and largest dimension is illustrated in Figure 7.1.
