Ken Bosnick
National Research Council Canada, Canada
Title: Nanocarbon composites for mechanical and barrier applications
Biography
Biography: Ken Bosnick
Abstract
Nanoscale allotropes of carbon, including carbon nanotubes (CNTs) and graphene nanoplatelets (GNPs), show a great deal of promise as functional fillers in nanocomposite materials. The extreme linear aspect ratios, strong sp2 carbon bonds, and high chemical stability all contribute to making CNTs ideal reinforcement fillers for mechanical applications. Conversely, the high aspect ratio planar nature of graphene and GNPs, along with their high impermeabilities, suggest applications as barrier materials. In this talk, we discuss our work on CNT – aluminum oxide (AO) composites for mechanical applications, including as ballistic armour, and GNP – polymer composites for high barrier applications, including oxygen barriers for food packaging and anti-corrosion coatings. CNT – AO hybrid structures are produced by depositing CNTs as conformal coatings on various AO materials, including powders and fabrics (see Figure 1(a)). The deposition is carried out in a large-volume chemical vapor deposition reactor, following a conformal catalyst deposition from solution or via an atomic layer deposition process. The CNT – AO hybrids are sintered into composite materials under high pressure and characterized for mechanical enhancements. Increases in fracture toughness of as high as 71% have been found from these CNT – AO composites. GNP materials are melt-processed with polyethylene (PE) and extruded into packaging films (see Figure 1(b)), which are characterized for their oxygen transmission rates. It is found that the GNP – PE films show comparable oxygen transmission rates to the neat PE films, indicating that further processing will be necessary to realize the desired enhancements. The GNP materials are also solution processed with epoxy (EP), cast onto steel substrates, and cured to form coatings. The efficacy of these coatings as anti-corrosion barriers is established by electrochemical and salt-fog corrosion tests. Early results suggest that the GNPs are enhancing the anti-corrosion performance of the EP films.
