STUDY ON CHAIN TRANSFER TO ACETIC-ANHYDRIDE OF THF POLYMERIZATION

In the presence of acetic anhydride, the catalyst containing protons m akes the polymerization complex.1,2 Thus, whether the living center, d uring the polymerization process of THF, transfers to the acetic anhyd ride is a difficult problem to answer. In this article, CH3COSbCl6 is used as the catalyst to avoid the interference of the protons. It is f ound that acetic anhydride is an effective chain transfer agent, by th e experiment at different temperatures for two systems in the presence or absence of acetic anhydride, and by the comparison of kinetic beha vior. In the system without acetic anhydride at the temperature of 7, 15, and 22-degrees-C, the propagation rate constants of THF, k(p) are 7.90, 14.23, and 23.35 10(-3) L/Mol . S, respectively. In the presence of acetic anhydride, k(p) are 1.51, 2.85, and 4.98 10(-3) L/Mol . S; and k(tr) are 2.04, 3.59, and 6.49 10(-4) L /Mol . S, respectively. (C ) 1994 John Wiley & Sons, Inc.