A kinetic study of the copolymerization of substituted anilines by ¹H NMR

Abstract

We investigated the kinetics of oxidative chemical copolymerization of 2‐methoxyaniline (OMA) with the following acidic substituted anilines (ANIAs): 2‐aminobenzoic acid, 3‐aminobenzoic acid, 2‐aminobenzenesulfonic acid and 3‐aminobenzenesulfonic acid by monitoring monomer depletion using 1H NMR spectroscopy. In order to characterize kinetically these new copolymerization systems, a semi‐empirical kinetic model for copolymerization systems with a large difference in monomer reactivities was used, whereas the monomer reactivity ratios were determined by employing the Kelen–Tüdõs (KT) method. Owing to the much higher reactivity of OMA compared to that of ANIA monomers, the conversion of OMA starts before that of ANIA and both the initiation and propagation rates are higher than those for ANIAs. The ANIA end‐conversion is much smaller (from 21 to 31%) than that of OMA (from 75% to 90%). © 2002 Society of Chemical Industry