Polymerization of acrylamide (M) in the presence of ultrasound and peroxomonosulfate (PMS) was carried out for the first time for various concentration ranges of monomer and initiator and various temperatures at a constant frequency of 1 Mhz. The rate of polymerization Rp was found to increase with increase in the concentration of monomer and initiator and found to depend on [M] and [PMS]1/2. The rate of disappearance of initiator (‐d[PMS]/dt) was also followed simultaneously under the experimental conditions and found to increase linearly with increase in [PMS]. A probable reaction mechanism was proposed on the basis of the observed results, and the individual rate constant were evaluated. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 2715–2719, 1998

Kinetics of oxidation of twelve α-amino acids (AA) by N-chlorosuccinimide (NClS) in aqueous alkaline media have been studied and compared with those of N-bromosuccinimide (NBS) oxidation. Analysis of the results shows that the observed rate of oxidation is first-order in [oxidant] and zero-order in [substrate]. The rate of oxidation increases with increase in [OH−]free in [NClS], the exception being the amino acids having β-alkyl substituent such as valine, leucine etc. Perusal of the results shows that NC1S/NBS reacts with α-amino acid anion to produce α-amino acyl hypohalite which then decomposes in the rate-determining step to give the products. The intermediate α-amino acyl hypohalite is identified by UV-visible absorption spectra. Glycine behaves differently from other amino acids in both oxidants. The proposed mechanism is consistent with the observed kinetics.

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