Functionalization of Carbon Nanotubes into Materials with High Compressive Strengths

Functionalization techniques will be developed to enhance the dispersion, interfacial interactions and reinforcement efficiency of carbon nanotubes and other graphite nanomaterials within hydraulic cements and ceramics. The project focuses on covalent functionalization techniques which preserve the structure and properties of nanomaterials, provide control over the degree of funcitonalization, and are scalable, energy-efficient, and economically and environmentally viable. Fluorination followed by derivative reaction, free radical and reductive functionalization techniques will be particularly emphasized. A key consideration in the project is to introduce inorganic nanoparticles upon functionalized nanomaterials (via in-situ synthesis or self-assembly) to enhance the interactions between nanomaterials and the inorganic matrix via chemical reaction and interdiffusion. The Phase I research will develop a theoretical framework to guide selection of the type and degree of functionalizaiton. Selected functionalization techniques will then be developed, and their impact on the structure and surface chemistry of nanomaterials will be investigated. Promising functional groups will be used as the base for synthesis or assembly of selected inorganic nanoparticles upon nanomaterials for effective interactions with representative groups of hydraulic cements and ceramics. Dispersions of functionalized nanomaterials (with or without tethered nanoparticles) will be homogenized together with dispersions of cement or ceramic particles, and will be consolidated and processed under pressure via moist curing or sintering. The resulting inorganic matrix nanocomposites will be subjected to laboratory tests for assessment of their structure, mechanical performance, and thermal and electrical characteristics. The competitive position of these nanocomposites will be assessed against conventional (micro-scaled) ceramic and cement composites, and potentially viable fields of applications will be identified. The follow-up Phase I Option will identify and screen strategies to refine the functionalization techniques for further improvement of the reinforcement efficiency of carbon nanotubes and other graphite nanomaterials within hydraulic cements and ceramics.