Synthesis and thermo-sensitive property of star poly(N-isopropylacrylamide) with α -D-glucose-based group

Polymers containing functional biological activity groups have potential biological application. A new type of initiator (Glu-Br) synthesized by α-D-glucose and excessive 2-bromo-isobutyrlbromide was used to initiate NIPAM polymerization by atom transfer radical polymerization in DMF/Water mixture solvent, HMTETA as ligand and CuCl as catalyst. A star polymer was obtained with the reaction molar ratio of [NIPAM]₀:[Glu-Br]₀:[CuCl]₀: [HMTETA]₀ = 100:1:5:1. The polymerization reached a low polydispersity (PDI = 1.15–1.47) with the linearity plot of the M_n,GPC against conversion, and the reaction time revealed the well-controlled polymerization by ATRP. The LCST(lower critical solution temperature) of the star polymer was increased with the molecular weight increasing. Used fluorescein dye molecules as model drug to loaded in the star polymer to measure its envelope ability. The results indicated that the polymer has a promising application in the field of drug controlled release system.