Characterization of styrene/methacrylic acid copolymers by 2D-NMR spectroscopy

Styrene/methacrylic acid copolymers were prepared by free-radical photopoly merization using the uranyl nitrate ion as the initiator. The copolymer com position was determined from H-1-NMR spectroscopy. The comonomer reactivity ratios determined using Kelen Tudos and nonlinear error in variable method s (EVM) are r(m) = 0.61 +/- 0.05 and r(s) = 0.14 +/- 0.07. The broad and ov erlapping H-1-NMR spectrum was assigned using the help of 2D TOCSY and NOES Y experiments. These methods were used to ascertain the various geminal, vi cinal, and spatial couplings between the protons. The methyl and methine pr otons also show configurational and compositional sensitivity. (C) 2001 Joh n Wiley & Sons, Inc.