Multilevel Hollow-Structured Particles through Halogen-Bond Regulated Polymer Assembly under 3D Confinement.

Engineering of hollow particles with tunable internal structures often requires complicated processes and/or invasive cleavage. Halogen-bond driven 3D confined-assembly of block copolymers has shed light on the engineering of polymer organization along with the fabricating of unique nanostructures. Herein, a family of multilevel hollow-structured particles (e.g., fully porous, multi-chamber, multi-shell, and concentric multi-layer architectures) is reported via halogen-bond regulated 3D confined-assembly of amphiphilic polymer networks. To do so, polystyrene-b-poly(2-vinyl pyridine)-b-poly(ethylene oxide) (PS-b-P2VP-b-PEO) amphiphilic triblock copolymer is selected, where P2VP blocks act as halogen acceptor. Meanwhile, poly(3-(2,3,5,6-tetrafluoro-4-iodophenoxy) propyl acrylate) (PTFIPA) is employed as halogen donor. Halogen-bond driven donor-acceptor linking between PTFIPA and P2VP block presented in PS-b-P2VP-b-PEO, can lead to the formation of supramolecular polymeric networks, along with the increased P2VP domain and tunable hydrophobic volume. Therefore, an adjustable packing parameter (p) is thus anticipated, which can enable the morphology transformation sequence until an equilibrium state is reached. Moreover, computer simulations are further utilized as the tool to interpret such morphologies transition and identify the precise distribution of each component. Benefiting from the tunable hollow structure and a substantial surface for transporting purpose, these structurally novel particles open perspectives toward promising applications including encapsulation, nanoreactor, and catalyst support.