Unimer Exchange Is not Necessary for Morphological Transitions in Polymerization‐Induced Self‐Assembly. (16th January 2023)

• Record Type: Journal Article
• Authors: Debrie, Clément; Coudert, Noémie; Guigner, Jean‐Michel; Nicolai, Taco; Stoffelbach, François; Colombani, Olivier; Rieger, Jutta
• Is Part Of: Angewandte Chemie. Volume 135:Number 8(2023)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2023-01-16
• Subjects: Block Copolymers -- Micelles -- PISA -- Rheology -- Vesicles; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202215134
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Polymerization‐induced self‐assembly (PISA) has established itself as a powerful and straightforward method to produce polymeric nano‐objects of various morphologies in (aqueous) solution. Generally, spheres are formed in the early stages of polymerization that may evolve to higher order morphologies (worms or vesicles), as the solvophobic block grows during polymerization. Hitherto, the mechanisms involved in these morphological transitions during PISA are still not well understood. Combining a systematic study of a representative PISA system with rheological measurements, we demonstrate that—unexpectedly—unimer exchange is not necessary to form higher order morphologies during radical RAFT‐mediated PISA. Instead, in the investigated aqueous PISA, the monomer present in the polymerization medium is responsible for the morphological transitions, even though it slows down unimer exchange. Abstract : We demonstrate that morphological transitions during radical RAFT‐mediated PISA in water do not require unimer exchanges. The monomer present in the polymerization medium enables morphological transitions although it unexpectedly slows down unimer exchange.