Star Polymers from Single-Chain Cyclized/Knotted Nanoparticles as a Core

Star polymers are comprised of a spatially defined “core-shell-periphery” structure. Their unique properties render them for diverse applications. One of the central challenges in the synthesis of star polymers is the design of a multifunctional core with many reaction sites for the conjugation with presynthesized arms or the initiation of the growth of arms. In this paper, it is demonstrated that the single-chain cyclized/knotted nanoparticles (SCKPs) with multiple vinyl functional groups can be synthesized by Cu⁰&Cu^II-mediated homopolymerization of bisphenol A ethoxylate diacrylate. Furthermore, the SCKPs with multiple pendant vinyl groups are used as the core and uniform amphiphilic star poly(β-amino ester)s with 17 high-molecular-weight arms are synthesized via a grafting-onto approach. This facile approach opens new avenues for the design and preparation of novel star polymers.