Complete structural characterization of 5,6-benzo-2-methylene-1,3-dioxepane (BMDO) monomer and its homopolymer is carried out using 1D and 2D NMR techniques. Copolymers of BMDO were made with MMA under ATRP reaction conditions. The copolymer compositions were obtained from H-1 NMR spectroscopy. The reactivity ratios for the copolymerization of BMDO with MMA were determined using the Kelen-Tud (o) over bars method and was found to be r(BMDO) = 0.53 and r(MMA) = 1.96. Compositional and configurational sequence analysis of copolymers is also done.