Functional nanostructures by NiCCo-PISA of helical poly(aryl isocyanide) copolymers

Abstract

Herein, we present a straightforward and versatile methodology to achieve functional polymeric nano-objects that contain helical cores. Nickel-catalysed coordination polymerisation-induced self-assembly (NiCCo-PISA) of helical poly(aryl isocyanide) amphiphilic diblock copolymers was conducted, affording micelles containing controllable quantities of activated ester groups (i.e. pentafluorophenyl esters) in the core that were subsequently modified using post-polymerisation modification (PPM) with amine nucleophiles. Three amines bearing different functionalities (alcohol, trifluoro and a maleimide dye) were successfully introduced into the nano-object cores as verified via NMR and FT-IR spectroscopy, while the retention of helicity within the resulting diblock copolymers was confirmed by circular dichroism (CD) spectroscopy. Changes in nanostructure morphology following modification were monitored by dynamic light-scattering (DLS), confirming the disassembly of the nano-objects when the core hydrophilicity was increased through the introduction of polar functionalities. These readily-synthesised and modified nanostructures containing helical cores are valuable scaffolds for use in applications such as circularly polarised luminescence, enantioselective chemistry or chiral separation.