One-Pot Synthesis of ABC Type Triblock Copolymers via in situ Click [3 + 2] and Diels−Alder [4 + 2] Reactions

Abstract

We report a one-pot synthesis of ABC triblock copolymers of poly(ethylene glycol)− (PEG−) polystyrene− (PS−) poly(methyl methacrylate) (PMMA), and poly(ε-caprolactone)− (PCL−) PS−PMMA by combining in situ click [3 + 2] and Diels−Alder [4 + 2] reactions. For this purpose, furan-protected maleimide end-functionalized PMMA, PS with α-anthracene and ω-azide end-functionality, and PEG or PCL with an alkyne end-functional group were reacted in N,N-dimehtylformamide (DMF) for 36 h at 120 °C in order to give the corresponding triblock copolymers. All polymeric precursors with narrow molecular weight distribution and well-defined chain-end functionalities were achieved from living polymerization methods, except PEG. The obtained polymers were characterized by 1H NMR (250 MHz), gel permeation chromatography (GPC), and differential scanning calorimetry (DSC) measurements.