Co‐Self‐Seeding Approach Toward Uniform Fiber‐Like Comicelles: Regulating Length and Distribution of Corona‐Forming Chains of Comicelles by Metal Ions

Co-self-seeding has emerged as a versatile approach toward obtaining uniform fiber-like comicelles with controlled length and morphology. The critic dissolution temperature (T-c) of seed micelles is one of the most important factors dictating the length and morphology of resulting comicelles. To vary the length and morphology of comicelles generated via co-self-seeding approach, one usually needs to use a new block copolymer (BCP) with different core-forming and/or corona-forming segment, which requires tedious synthesis. Herein, a postmodification strategy is reported to tune the T-c of seed micelles by using metal ions as additives, rather than varying the chemical structure of BCPs. A pair of BCPs of OPV5-b-P2VP(42) and OPV5-b-PNIPAM(49) (OPV = oligo(p-phenylene vinylene), P2VP = poly(2-vinylpyridine), PNIPAM = poly(N-isopropyl acrylamide), subscripts are the number of repeat unit for each block) as models. The T-c of seed micelles of OPV5-b-P2VP(42) is significantly enhanced by adding Cu2+ ions, owing to the coordination of pyridyls to Cu2+ ions, whereas the T-c of seed micelles of OPV5-b-PNIPAM(49) is hardly affected by Cu2+ ions with the presence of P2VP chains. In this way, the length and distribution of corona-forming chains of resulting fiber-like comicelles can be easily tuned by the addition of Cu2+ ions.