ON THE KINETICS AND INITIATION MECHANISM OF ACRYLAMIDE POLYMERIZATION USING THE CERIC ION ACETOACETANILIDE SYSTEM AS INITIATOR

It is found that acetoacetanilide (system. name: N-phenyl-3-oxobutanamide) possesses a very high reactivity towards ceric ions, Ce4+, in initiating the polymerization of vinyl monomers. In the presence of acetoacetanilide, the rate of the acrylamide polymerization is larger by a factor of 30 than the rate of initiating by ceric ions alone. The reaction orders were 0,58, 0,75 and 1,2 with respect to acetoacetanilide, ceric ion and acrylamide concentration, respectively. The activation energy of the acrylamide polymerization initiated by ceric ion/acetoacetanilide is only 12,9 kJ/mol. According to the IR spectrum, fragments of acetoacetanilide are present in the polymer produced by the ceric ion redox initiator comprising acetoacetanilide. The C-centered and N-centered primary radicals generated via redox reaction of ceric ion and acetoacetanilide were detected by spin trapping and electron paramagnetic resonance. An initiation mechanism of the ceric ion/acetoacetanilide initiated polymerization is proposed on the basis of experimental results.Polymer ScienceSCI(E)3ARTICLE3823-83119