THE REACTION OF NITROXYL RADICALS WITH METALPHENOLS IN A POLYMERIC MATRIX AND THE ROLE OF REAGENT VOLUME

The kinetics of the reactions of 2,2,6,6-tetramethyl-4-benzoyloxypiper idine-1-oxyl, zoyloxyimino)-2,2,6,6-tetramethylpiperidine-1-oxyl with -hydroxybenzylidene)-4-hydroxy-3,5-dimethylaniline and its complexes w ith Co2+, Fe2+, and Ni2+ in polypropylene (PP) was investigated. The r ate constants were measured and the activation energies and frequencie s of rotational diffusion for radicals were calculated. The reactions were shown to be bimolecular within the kinetic region, the rate const ants in PP being lower than those in solution; this difference increas ed with the increase in the volume of both reagents. Some peculiaritie s of the reactions in the solid phase are explained within the framewo rk of the rigid-cage concept.