Experimental and theoretical quantum-chemical study of radical polymerization in the presence of nitroxyl radicals

The free-radical polymerization of acrylic and some vinyl monomers in the p resence of stable nitroxyl radicals and their sources, nitrones and nitroso compounds, was studied. Based on the kinetics of the process and the molec ular mass characteristics of the synthesized polymers, it was established t hat sterically hindered nitroxyl macroradicals produced in the course of po lymerization may control polymer chain growth in the interval between 50 an d 70 degreesC. Experimental data are supported by the results from quantum- chemical calculations of polymer radicals and their complexes with stable s pin-adducts obtained in terms of the density functional theory using the B3 LYP/6-31G and B3LYP/6-31G(d) programs.