The Polymer Society of Korea

Abstract

End-functionalization of block copolymers is a powerful strategy for regulating self-assembled nanostructures by controlling molecular interactions at polymer termini. Selective ion-dipole interactions at chain ends enable complex network nanostructures by alleviating packing frustration, yet the role of dielectric constant of polymer chains in terminal interactions remains largely unexplored. Here, we investigate amphiphilic diblock copolymers in which ionic moieties are selectively introduced at either the hydrophobic or hydrophilic block termini to elucidate how end-group aggregation and/or Coulombic interactions govern chain stretching. With added metal salts, salts preferentially localize at end-groups of low-dielectric hydrophobic polymers, whereas in hydrophilic polymers salts diffuse throughout the block, diminishing the directionality of terminal interactions. This yields distinct self-assembled morphologies, and the resulting structure-ion transport properties are examined.