LIVING CARBOCATIONIC POLYMERIZATION .62. LIVING POLYMERIZATION OF STYRENE, P-METHYLSTYRENE AND P-CHLOROSTYRENE INDUCED BY THE COMMON ION EFFECT

The effect of common anion producing salt, tetrabutylammonium chloride (n-Bu4NCl), on the livingness and kinetics of styrene (St), p-chloros tyrene (pClSt), and p-methylstyrene (p MeSt) polymerization initiated by the 2-chloro-2,4,4-trimethylpentane (TMPCl)/TiCl4 system has been i nvestigated. Uncontrolled (conventional) carbocationic polymerization of St and p MeSt can be converted to living polymerization by the use of n-Bu4NCl. Under similar conditions the polymerization of p ClSt is living even in the absence of n-Bu4NCl, although the molecular weight distribution (MWD) of the polymer becomes narrower in the presence of this salt. The apparent rates of polymerizations decrease in the prese nce of n-Bu4NCl in proportion with the concentration of the salt. The rate of living polymerization of p ClSt is noticeably lower than that of St, while that of p MeSt is higher. The apparent rate constants, k( p)(A), of these polymerizations have been determined, and the effects of the electron donating p Me- and electron withdrawing p Cl-substitue nts relative to the rate of St polymerization have been analyzed. [For part LXI, see J. Si and J. P. Kennedy, Polym. Bull., 33, 651 (1994)]. (C) 1997 John Wiley & Sons, Inc.