Living carbocationic polymerization. LXII. 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-chlorostyrene (pClSt), and p-methylstyrene (pMeSt) polymerization initiated by the 2-chloro-2,4,4-trimethylpentane (TMPCl)/TiCl₄ system has been investigated. 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 presence 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-substituents 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)]. © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 3341–3347, 1997