Intermicellar Polymerization and Intramicellar Cyclization: A Supramolecular Ring–Chain Competition Reaction

Abstract

At the molecular level, intermolecular polymerization can compete with its intramolecular cyclization, which is known as a ring−chain competition reaction. However, this competitive phenomenon has rarely been observed in higherlevel systems. Herein, we report a supramolecular ring−chain competition reaction between the intermicellar polymerization and intramicellar cyclization of rodlike micelles assembled from rod− coil graft copolymers. Nanowires and toroidal micelles are the chain-like and ring-like products of the two supramolecular reactions, respectively. When the reaction conditions (solvent composition or temperature) are varied, the competition of the two supramolecular reactions is induced, and their dynamic competition relation and equilibrium constants can be regulated by the reaction conditions. The combination of experiments and theoretical simulations reveals that the interplay of the core/shell interfacial energy, the bending energy of rodlike micelles, and the end-capping energy determines such ring−chain competition. This study presents an advance in supramolecular self-assembly and provides a progressive way to construct complex hierarchical nanostructures.

π–π Interlocking Effect for Designing Biodegradable Nanorods with Controlled Lateral Surface Curvature

“…Polypeptides are promising candidates for biomedical applications due to their close affiliation to proteins. − Compared to other degradable polymers, polypeptides feature various secondary structures, including α-helices and β-sheets. − This feature has a huge impact on their self-assembly behavior. ,− Poly-γ-benzyl- l -glutamate (PBLG) is a particularly interesting polypeptide that adopts the head-to-tail (HTT) arrangement in helicogenic solvents (such as dioxane, ethylene dichloride, and chloroform) because each α-helical PBLG molecule has a permanent dipole moment along the direction of its rod axis (Scheme S1A,B). − With the introduction of a poor solvent, these HTT chains further aggregate under the side-by-side antiparallel (SSA) arrangement (Scheme S1C) and also due to the permanent dipole moments .…”

Reaction‐induced morphology control in block copolymers

“…Most commonly, this can be accomplished through polymerization‐induced self‐assembly (PISA) which increases the segregation strength of the BCPs and/or their immiscibility with the solvent in the reaction medium through the addition of repeat units during polymerization 46,47 . The versatility of PISA has led to a vast body of literature and multiple detailed reviews on various synthetic pathways and diverse material systems 48–54 . To provide a brief introduction, PISA typically relies on living polymerization methods (reversible addition–fragmentation chain transfer (RAFT) polymerization, 27,34,35 atom transfer radical polymerization (ATRP), 38–40 anionic polymerization, 41,42 etc.)…”

Modulating living crystallization-driven self-assembly behaviors of oligo(p-phenylene ethynylene)-containing block copolymers and micellar stability by solvent and corona-forming chain length

“…Li, Lin, Xu, Manners and co-workers also reported the formation of hierarchical fibril superstructures via the end-to-end coupling of fiber-and oval-like micelles containing a liquid crystalline or crystalline segment, including a poly(cholesteryl methacryloyloxy ethyl carbonate), poly(γ-benzyl-L-glutamate), PFS or poly(ε-caprolactone) core-forming block. [61][62][63][64][65] In these systems, the end-to-end coupling process is usually driven by reducing the overall core/corona interfacial energy from a thermo-dynamic point of view. Most of the connections between the subunits of diamond-and platelet-like micelles appeared to be in the regions of acute angles of diamond-and platelet-like micelles as indicated by red arrows in Fig.…”