An Efficient Route to Macromonomers via ATRP and Click Chemistry

Abstract

The combination of atom transfer radical polymerization (ATRP) and click chemistry was employed to prepare well-defined ω-(meth)acryloyl macromonomers in an efficient manner. Poly(n-butyl acrylate) (PBA), polystyrene (PS), and PS-b-PBA were prepared by ATRP and subsequently derivatized to contain azido end groups. The reaction of the azido-terminated polymers with alkyne-containing acrylate and methacrylate monomers resulted in near-quantitative chain end functionalization. Macromonomers of various molecular weights [PBA: Mn = 2.2−6.4 × 103 g/mol (DPn = 16−49); PS: Mn = 3.2−5.9 × 103 g/mol (DPn = 29−55)] and architectures were prepared by this method. The end group transformations required to incorporate the polymerizable functionality were accomplished either as a stepwise series of discrete reactions or as an in situ process, wherein azidation was immediately followed by azide−alkyne coupling in situ. In both cases, the degree of end group functionalization generally exceeded 90%. To demonstrate polym...