Molecular Alignment of a Meta-Aramid on Carbon Nanotubes by In-Situ Interfacial Polymerization.

Molecularly organized nanocomposites of polymers and carbon nanotubes (CNTs) have great promise as high-performance materials; in particular, conformal deposition of polymers can control interfacial properties for mechanical load transfer, electrical or thermal transport, or electro/chemical transduction. However, controllability of polymer-CNT interaction remains a challenge with common processing methods that combine CNTs and polymers in melt or in solution, often leading to non-uniform polymer distribution and/or aggregation of CNTs. Here, we demonstrate CNTs within net-shape sheets can be controllably coated with a thin, conformal coating of meta-aramid by simultaneous capillary infiltration and interfacial polymerization. We determine that π interaction between the polymer and CNTs results in chain alignment parallel to the CNT outer wall. Subsequent nucleation and growth of the precipitated aramid forms a smooth continuous layered sheath around the CNTs. These findings motivate future investigation of mechanical and interfacial properties of the resulting CNT composites, and adaptation of the in-situ polymerization method to other substrates.