David G. Bucknall, Haskell W. Beckham and Yonathan S. Thio Georgia Institute of Technology
Project Abstract
Polymer-silicate nanocomposites will be examined in situ with X-ray scattering under large-strain conditions that mimic (1) processing and (2) deformation to fracture. Simultaneous small-angle and wide-angle X-ray scattering will be employed to collect real-time structural data during biaxial stretching conditions which match commercial thermal blown film processing, and during uniaxial stretching for large-strain deformation measurements. Nanocomposite samples will be characterized before and after the processing and deformation studies using complementary techniques that include transmission electron microscopy, thermal and mechanical property measurements. These experimental studies will be conducted in close cooperation with a multi-scale modeling research effort to create a predictive tool for designing nanocomposites for a given application. The proposed research will be integrated with graduate and undergraduate education at Georgia Tech and will at the same time provide opportunities for outreach to local high schools. The proposed research also has broad implications for technologies which are beginning to commercially exploit polymer-silicate nanocomposites in applications from packaging to automotive components. The empirical development of structure/property relationships in these nanocomposite materials has lead to knowledge of types of morphologies that can be formed from different starting recipes, and how this relates to their observed properties. Despite this, relatively little is known about how nanocomposite morphologies reach their characteristic forms during processing, nor how these structures deform under large-scale deformation to fracture. This knowledge, which is needed to complement the comprehensive modeling studies being undertaken by our collaborators, can be provided by conducting in-situ studies of nanocomposite processing and deformation.
