Extended white-box cyclophanes for the synthesis of mechanically interlocked derivatives of single wall carbon nanotubes in water

Abstract

Single-walled carbon nanotubes (SWNTs) possess exceptional properties, but their inherent tendency to agglomerate has limited their exploitation. Here, we present a strategy for the aqueous synthesis of mechanically interlocked nanotube derivatives (MINTs) by combining two complementary cationic molecules that not only assist in dispersing SWNTs but also assemble around them through dynamic acyl hydrazone linkages. The resulting MINTs integrate the stability of covalent modification with the unique versatility of acyl hydrazone functionalities, enabling post-functionalization of the nanotube surface. Comprehensive characterization confirmed the successful formation of these interlocked structures, accompanied by smaller fractions of other supramolecular aggregates, while preserving the SWNT integrity. Importantly, the acyl hydrazone moieties impart intrinsic hydrolytic susceptibility, facilitating the controlled recovery of pristine nanotubes after use. This waterborne MINT platform offers a promising route for developing functional SWNT materials tailored for applications requiring both stability and reversible modification in aqueous environments.