LIVING CATIONIC POLYMERIZATION OF STYRENE BY 1-CHLOROETHYLBENZENE/TIN(IV) CHLORIDE IN CHLOROFORM

Abstract

Living cationic polymerization of styrene in the presence of 1-chloroethylbenzene (1-CEB)/SnCl4 as an initiating system has been investigated in chloroform at -15 to +20-degrees-C. The best results were obtained at -15-degrees-C. Under these conditions, the number-average molecular weight (M(n)BAR) of the products increases linearly with increasing monomer conversion. The molecular weight of the polymer produced could be further increased by adding additional monomer. The molecular weights are in good agreement with the calculated values assuming that one living polymer chain is formed per one 1-CEB molecule. The molecular weight distributions of the polymers obtained are narrow (ratio of weight- to number-average molecular weights 1,07 less-than-or-equal-to M(w)BAR/M(n)BAR less-than-or-equal-to 1,17). The living character of these polymerizations depends on the polarity of the solvent and on temperature.