The instrumentation funded by this award will support a systematic investigation of solid-state shear pulverization (SSSP) for creating polymer nanocomposites with improved barrier properties relative to those fabricated using conventional melt compounding. The innovative SSSP technique can overcome many of the common challenges associated with conventional techniques for producing effective and stable nanocomposites with well-dispersed and exfoliated nanofillers (e.g., clay, carbon nanotubes, and graphite). Thus, SSSP has significant potential to advance fundamental structure-property relationship elucidation in nanocomposites and facilitate development of superior hybrid materials for use in new engineering applications. The main objectives of this research are: (1) to understand the relationship between SSSP processing parameters and the structure and properties of the resulting nanocomposites via a systematic parametric study; (2) to develop novel high-performance polymer nanocomposites tailored for specific industrial applications by controlling the solid-state pulverization conditions; and (3) to evaluate the morphology and barrier properties of the nanocomposites created by SSSP via direct comparison with those of the unmodified polymer and nanocomposite specimens created by melt compounding.
The instrumentation includes a bench-scale twin-screw extruder/solid-state shear pulverizer that is custom designed for continuous fabrication of polymer nanocomposites in the melt or solid state. The instrumentation also includes precision analyzers for measurement of water vapor and oxygen permeability, pellet and powder feeders for delivering polymer resin and nanofillers, and a water trough/pelletizer system to cool, collect, and size melt-compounded extrudate. This equipment will be used in conjunction with existing instruments to conduct the proposed research and support a long-term research program for both PIs. In addition, the equipment will enhance research and educational opportunities for underrepresented groups and facilitate cross-disciplinary collaborations and outreach both on and off the Bucknell campus. The PIs represent different engineering disciplines and will work together with students from different science and engineering concentrations. Moreover, a portion of the research involves a multi-institutional partnership with a Research I university and an exclusively undergraduate, technology-focused institution, thereby stimulating cross-fertilization and promoting shared use of the instrumentation. The outcomes of the research will be disseminated to the international science and engineering communities and are expected to attract interest from potential industrial partners.
