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Abstract

The activity of Ph₃CZX_n in the initiation of polymerization of 1-chloro-2,3-epoxypropane decreases in dependence on ZX_n in the following series AsF₆^(-) ≥ SbF₆^(-) ##i SbCl₆^(-) > AlCl₄^(-) > SnCl₅^(-) > TiCl₅^(-). The polymerization initiated by Ph₃CSbF₆ is a first-order reaction both with respect to the monomer and to the catalyst. The following values were determined for the rate constants of initiation, propagation, and termination, respectively: k_i = 3 . 10^-6 mol^-1 l s^-1; k_p = 9 . 10^-2 mol^-1 l s^-1; k_t = 2 . 10^-4 mol^-1 l s^-1. The initiation occurs via a hydride-ion transfer from 1-chloro-2,3-epoxypropane to the triphenylmethyl cation. The oxonium ion formed by Ph₃C⁽⁺⁾ addition on 1-chloro-2,3-epoxypropane presumably does not take part in the initiation; the equilibrium constant of formation of this adduct K_e is 3.0 . 10^-1 mol^-1 l. Oligomers are n-multiples of monomeric epichlorohydrine, and products of P_n 4-7 have mostly cyclic structure.