Methyl methacrylate/ N ‐( o ‐/ m ‐/ p ‐chlorophenyl) itaconimide copolymers: Microstructure determination by NMR spectroscopy

Homopolymerization and copolymerization of N ‐( o ‐/ m ‐/ p ‐chlorophenyl) itaconimide with methyl methacrylate was carried out by taking varying mole fractions (0.1 to 0.5) of N ‐aryl substituted itaconimide monomers in the initial feed using azobisisobutyronitrile as an initiator and tetrahydrofuran as the solvent. The copolymer composition was determined by 1 H‐NMR spectroscopy using the ratio of proton resonance signal intensity attributed to OCH 3 of MMA (δ = 3.5–3.8 ppm) and the aromatic protons (δ = 7.0–7.5 ppm) of N ‐( o ‐/ m ‐/ p ‐chlorophenyl) itaconimide. The comonomer reactivity ratios were determined using Kelen–Tüdos and nonlinear error in variable methods. The reactivity ratios obtained by nonlinear error in variable methods were r 1 (PI) = 1.26/ r 2 (MMA) = 0.35; r 1 (MI) = 1.21/ r 2 (MMA) = 0.34; and r 1 (OI) = 0.78/ r 2 (MMA) = 0.34. The carbonyl carbon signals of MMA (M) as well as N ‐aryl itaconimide (I) copolymers were used for the determination of the sequence distribution of M‐ and I‐centered triads. The sequence distribution of M‐ and I‐centered triads determined from 13 C{ 1 H}‐NMR spectra of the copolymers are in good agreement with the triad concentrations calculated using the Alfrey–Mayo statistical model and Monte Carlo simulation method. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 91: 2016–2027, 2004