LIVING CARBOCATIONIC POLYMERIZATION .46. LIVING ISOBUTYLENE POLYMERIZATION INDUCED BY THE COMMON ION EFFECT

Conventional cationic polymerization can be converted into living carbocationic polymerization (Lc+Pzn) by the introduction of common anion into the charge. Thus the conventional polymerization of isobutylene (IB) induced by the 2-choro-2,4,4-trimethylpentane (TMPCl)/TiCl4 combination yields LC+Pzn of IB upon the addition of tetrabutyl ammonium chloride (n-Bu4NCl), most likely due to the n-Bu4NCl + TiCl4 half-arrow-right-over-half-left n-Bu4N+ + TiCl5- equilibrium. A kinetic model has been developed and tested which corroborates these propositions. By this model we have gained for the first time quantitative insight into the quasiliving equilibrium.