Synthesis of multiarm star block copolymer based on host-guest inclusion complexation

Abstract

Supramolecular multiarm star block copolymer ((CD-PEG)p-(Ada-PS)n-polyDVB) was prepared by host-guest interaction of -cyclodextrin ( -CD) end functionalized polyethylene glycol (-CD-PEG) and adamantane peripherally functionalized multiarm star polymer ((Ada-PS)n-polyDVB). The -CD-PEG was synthesized by copper-catalyzed azide/alkyne cycloaddition reaction (CuAAC) of alkyne functional PEG with mono azide functional β-CD (β-CD-N3). Adamantane functional polystyrene (Ada-PS) was prepared by atom transfer radical polymerization (ATRP) of styrene (St) and was allowed to react with divinyl benzene (DVB) as a linking agent giving (Ada-PS)n-polyDVB multiarm star polymer. The structures of -CD-PEG and (Ada-PS)n-polyDVB multiarm star formation were determined by 1H NMR and GPC. 2D ROESY NMR and DLS analysis of (CD-PEG)p-(Ada-PS)n-polyDVB were carried out to validate the formation of the inclusion complex. The evidence of increased molecular weights and size distributions supported the supramolecular multiarm star block copolymer formation.