M.B. Jakubinek, Y. Martinez Rubi, B. Ashrafi, B. Simard, C.T. Kingston
National Research Council Canada,
Keywords: carbon nanotubes, CNT, composites, fabric
Summary:Carbon nanotubes (CNTs) have long been considered promising for development of advanced composite materials, due to their unsurpassed properties along with low density, and they are now appearing in an increasing number of composites applications from sporting goods to aerospace. Integration of nanotubes in the form of fabrics or other preformed assemblies (sheets, films, fibers, etc.) simplifies their handling and allows for higher nanotube content, which is needed to better leverage their properties in advanced composite materials. Indeed, the highest reported mechanical properties for bulk nanocomposite materials in the literature were achieved in composites formed from long, aligned, high-density CNTs; however, CNTs in this form are not yet broadly available. We have explored production of non-woven nanotube-polyurethane fabrics made from broadly available, industrial-grade MWCNTs and SWCNTs via a one-step filtration method wherein control of a solvent/non-solvent system results in a nonwoven fabric of polyurethane-coated nanotubes. The approach provides for tailoring of the nanotube:polymer ratio and control of the density/porosity of the nonwoven nanocomposite fabrics, which have been subsequently layered, laminated or infused to produce thick nanocomposites or integrated with conventional composites. The production and properties of these high-CNT-content composites will be highlighted along with recent scale-up/continuous manufacturing progress and multifunctional composites application cases such as for heating, electromagnetic shielding and flame resistance.