Nitrilotriacetic acid (NTA) coupled with commonly used metal oxidants was used as an initiator for the aqueous polymerization of acrylamide (AM) under neutral or acidic conditions. The cerium(IV)-NTA pair under neutral conditions behaved as the most promising redox initiator. In order to find the mechanism of generation of free radicals and to determine the complex formation constant (K) and the disproportionation constant (kd), blank tests for the reactions of Ce(IV) with NTA were conducted under conditions of neutral, 1 N HNO3 and 1 N NaNO3, respectively. The mechanism was further confirmed by 13C and 1H n.m.r. spectra and the kinetic parameters for the aqueous polymerization of AM were evaluated. The effects of additives on the polymerization were studied and the use of the Ce(IV)-NTA redox pair for other aqueous polymerization systems such as acrylic acid (AA), acrylonitrile (AN) and methyl methacrylate (MMA) was also studied.
All Science Journal Classification (ASJC) codes
- Organic Chemistry
- Polymers and Plastics
- Materials Chemistry