Synthesis and characterization of five-arms star polymer of N-vinyl pyrrolidone through ATRP based on glucose

Glucose based five arms atom transfer radical polymerization initiator was synthesized. This initiator was used to synthesize 5-arms star polymer of N-vinyl pyrrolidone (NVP) through controlled radical polymerization. The ratio of reactants were kept as 1:1:2: 200 (initiator:Cu(I)Br:bpy:NVP). The rate of reaction with respect to NVP was found to be first order, and number-average molecular weight increases linearly with temperature up to 90 °C. The activation energy (Ea = 29.75 kJ mol−1) and enthalpy (ΔH‡ = 26.73 kJ mol−1) were found to be in a good agreement with each other for activated complex, and negative value of entropy of activation (ΔS‡ = −219.12 J mol−1 K−1) supports the highly ordered transition state.