Tang, Q.; Ren, H.; Kochovski, Z.; Cheng, L.; Zhang, K.; Yuan, J.; Zhang, W.: Topological Effects on Cyclic Co-Poly(Ionic Liquid)s Self-Assembly. Macromolecular Chemistry and Physics 224 (2023), p. 2200134/1-7
10.1002/macp.202200134
Open Access Version
Abstract:
Topological geometry of poly(ionic liquid)s (PILs), such as brush-like, knot-like, hyperbranched and randomly coiled, often exerts a strong influence on their self-assembly behaviors. As a primary topological form, the cyclic topology-derived effects have not been investigated on PILs, which concerns synergy of charges and zero chain end. Herein, linear and cyclic poly(ionic liquid) copolymers (co-PILs) with randomly distributed counter anions of B(Ph)4− and Br− by a template method in combination with a follow-up partial anion exchange is prepared. The self-assembly phenomena of linear and cyclic co-PILs are studied in selective solvents, where the hydrophobic counter anions B(Ph)4− and hydrophilic counter anions Br− aggregated to form cores and corona in the assembled nanospheres, showing the average size of cyclic co-PILs nanospheres is 46.2% smaller (≈120 nm) than linear co-PILs nano-assemblies (≈176 nm). Based on the CGMD simulations, the authors speculate that the spherical aggregates are formed by transitioning from micelles with gradient block-like structures, which formed by enriched hydrophobic counter anions in the core and enriched hydrophilic counter anions in the corona. These results indicate a novel synergy of topology effects and dynamic anion movements, as revealed by cyclic co-PIL self-assembly in this work.