Controlled synthesis of linear and multi ARM amphiphilic copolymers consisting of P4VP and PCL for tailored nano-aggregate formation

Formation of nanoaggregates driven by the topological structures of P4VP-PCL copolymers. [Display omitted] •-Linear (AB) and multi-arm (ABX) structures based on PCL have been developed.•-The copolymer's topology has been identified as the crucial factor for aggregate formation, irrespective of the nature of the medium.•-Control over copolymer topologies allows the regulation of the types of nanoaggregates formed in solution.•-Multi-arm copolymers form stable vesicles in a very short time of 30 min and with a very low CAC point. This work focuses on the synthesis and characterization of amphiphilic block copolymers with varying architectures using controlled polymerization via RAFT polymerization. The study explores the production of diverse nano-aggregates, ranging from micelles to complex structures like vesicles, by leveraging the destabilization of micelle formation through multi-arm topologies. The chosen polymer chains, P4VP and HEMA-PCL, exhibit inter and intramolecular interactions that facilitate phase separation and the formation of nano-aggregates in different solvent mixtures. The Structural characterizations using NMR, FTIR, and SLS have demonstrated good control over the architecture of the copolymers. The physicochemical properties of the copolymers are discussed, along with a detailed analysis of supramolecular association in different solvent systems, revealing the strong influence of copolymer architecture and arm number on the nature of the formed aggregates. The multi-arm structure stabilizes at much lower CAC and in very short time (30 min) compared to that found in the case of the linear structure. In addition, the results shown that, the multi-arm structure always allows the formation of vesicles no matter what the selective solvent is, which indicate that the formation of the aggregates is driven by the topology of copolymer and note by the medium polarity.