Water-soluble poly(2-hydroxyethyl acrylate) (PHEA)-based core cross-linked star polymers were efficiently synthesised with high macroinitiator-to-star-conversion (>95 %) in a one-pot system via single electron transfer-living radical polymerisation. The star polymers display excellent water solubility and the pendant hydroxyl groups provide a platform for facile post-functionalisation with various molecules. In demonstrating this, a photo-isomerisable molecule, 4-(phenylazo)benzoic acid was conjugated onto the preformed stars through partial esterification of the available hydroxyl groups (5–20 %). The azobenzene functionalised stars were subsequently employed to form reversible inclusion complexes with α-cyclodextrin.
A one-pot strategy from ring-opening metathesis polymerization was employed to prepare AIE-active star polymers, which were designed to have multi-responsive fluorescence to varied stimuli including pH, CO2, and metal ions.
Star polymers of sodium styrenesulfonate with controlled arm length were prepared in a one-pot polymerization. Sodium styrenesulfonate was first polymerized with controlled molecular weight and narrow polydispersity by stable free radical polymerization. Poly(sodium styrenesulfonate) was terminated with divinyl benzene and star polymers prepared via stable free radical coupling of vinylic terminal groups. Star polymers based on arms of 20 and 32 repeat units possessed ~33 and ~41 arms per star respectively. Formation of star polymers with much longer arms was limited by poor coupling kinetics.
A one-pot tandem strategy for the synthesis of asymmetric star polymers was developed. Two wavelengths of light were used to provide spatial and temporal control for the reactions. A series of stars were synthesised using this procedure giving well-defined structures.
Fe(0) powder-catalyzed one-pot reaction was successfully employed to design linear and star polymers in a well-controlled manner by combining ambient temperature living radical polymerization and click chemistry.
Photo-controlled one-pot strategy for the synthesis of asymmetric three-arm star polymers