Nitroxide-Mediated Alternating Copolymerization of Vinyl Acetate with tert-Butyl-2-trifluoromethacrylate Using a SG1-Based Alkoxyamine

Unique alternating copolymers based on vinyl acetate (VAc) and tert-butyl-2-trifluoromethacrylate (MAF-TBE, a nonhomopolymerizable monomer under radical conditions) have been synthesized by nitroxide-mediated polymerization (NMP) using a SG1-based BlocBuilder alkoxyamine (MAMA-SG1) at moderate temperature (at 40 degrees C) in dimethyl sulfoxide. First-order kinetics and linear evolutions of the molecular weight (up to 17100 g mol(-1)), maintaining low dispersity values (D <= 1.33), confirmed the controlled nature of the copolymerization. Interestingly, none of the starting monomers could undergo homopolymerization under the NMP condition initiated by MAMA-SG1. The resulting alternating copolymers were characterized by H-1, C-13, F-19, and P-31 NMR spectroscopies and size exclusion chromatography (SEC). The poly(VAc-alt-MAF-TBE) copolymer is amorphous and exhibited a single glass transition temperature of 59 degrees C. This is the first report of nitroxide-mediated (co)polymerization of VAc leading to well-defined copolymers with satisfactory yields. The results presented in this study established a new route via NMP toward the synthesis of strictly 1:1 alternating fluorocopolymers that can display diverse functionalities.