Synthesis of Hyperbranched Glycopolymers via Self-Condensing Atom Transfer Radical Copolymerization of a Sugar-Carrying Acrylate

Hyperbranched glycopolymers were synthesized by self-condensing vinyl copolymerization (SCVCP) of an acrylic AB* inimer, 2-(2-bromopropionyloxy)ethyl acrylate (BPEA), with 3-O-acryloyl-1,2:5,6-di-O-isopropylidene-α-d-glucofuranoside (AIGlc) via atom transfer radical polymerization (ATRP), followed by deprotection of the isopropylidene protecting groups. Homopolymerization of AIGlc with the CuBr/pentamethyldiethylenetriamine (PMDETA) catalyst system in solution resulted in linear poly(AIGlc) having controlled molecular weights and narrow molecular weight distribution, which were characterized using GPC, GPC/viscosity, and MALDI−TOF mass spectrometry. The catalyst system could be applied for SCVCP to synthesize hyperbranched poly(AIGlc)s, in which the molecular weights, the composition of AIGlc segment, and the branched structures can be adjusted by an appropriate choice of the comonomer ratio, γ. Deprotection of the isopropylidene protecting groups of the branched poly(AIGlc)s resulted in water-soluble glycopolymers with randomly branched architectures.