The research objective of the award is to study the fabrication of organic-inorganic hybrid nanostructured materials in such a way as to create strong adhesion or bond between the constituent phases of a composite, while retaining the individual properties of the constituent phases. The fabrication process involves direct nucleation and growth of polymer nanocrystals along the axis of carbon nanotubes with the help of high pressure. These polymer nanocrystals are responsible for the strong bond between the nanotube and the matrix phases in the nanocomposite. Furthermore, the fabrication will also provide the ability to tune the structural morphology of the hybrid structure at different length-scales by controlling the crystallization pressure and liquid undercooling or the degree to which the polymer melt is cooled below its equilibrium crystallization temperature. Thermodynamic models with predictive capabilities will be developed for a wide range of nanoparticle-polymer systems and will be based on thermodynamically-driven chemical interactions at the polymer crystal-nanoparticle interface. Successful completion of the research will provide generic guidelines governing pressure-induced fabrication of hybrid nanostructured materials for a variety of applications.
An important advantage of direct nucleation of polymer crystals on carbon nanotubes is to eliminate the need to modify the surface or functionalization of carbon nanotubes prior to their use in the fabrication of hybrid nanocomposites. Thus, the un-modified carbon nanotubes will retain their extraordinary electrical, optical, and mechanical properties and their full potential, when present in small amounts, can be realized. This aspect will be of particular interest in the development of next generation of photovoltaic and data storage devices. Moreover, the direct polymer nanocrystal nucleation method will overcome the technological barrier of obtaining strong adhesion between the constituent phases and thereby will open-up a new avenue for fabricating high performance materials. The confluence of understanding and the realization of processing of polymers containing nanoparticles under pressure-induced nucleation conditions have far reaching impact in applications such as barrier liners in storage tanks and fuel liners for cryogenic fuel storage in aerospace.
