查看文章

Solution copolymerization of acrylonitrile (AN) with various vinyl acids, ie, acrylic acid (AA), methacrylic acid (MAA), and itaconic acid (IA), was carried out in DMF at 70 C using a, a'-azobisisobutyronitrile (AIBN) as an initiator with an acidic monomer of 0.012-0.092 mol%. Copolymers were characterized by FTIR, CHN analysis,'H-and 13C-NMR, and viscometry. The reactivity ratios were calculated using Fineman-Ross and Kelen-Tudos methods. In all three systems, the value of rl (AN) is much less than the value of r2. However, the rz (MAA) is higher than r2 of (AA) and (IA). The reactivity ratios were calculated using Q and e schemes also. The results are in good agreement with experimentally calculated data. The tacticity and sequence length distribution of these copolymers were calculated using 13C-NMR from C= N and CH signals. It was observed that the isotacticity of acrylonitrile-itaconic acid copolymer P (AN …