T. Saegusa, S. Matsumoto, Y. Hashimoto
1970
Citations
0
Influential Citations
16
Citations
Journal
Polymer Journal
Abstract
AbstractA kinetic study on the polymerization of tetrahydrofuran catalyzed by the system AlEt3–H2O(2:1)-promoter was carried out. Epichlorohydrin, propylene oxide and β-propiolactone were employed as the promoter. The concentration of propagating species [P*] was determined at several times during polymerization by means of a new method in which the propagating species at polymer chain end was converted into the corresponding phenyl ether by end-capping with sodium phenoxide, and the phenyl ether group was analyzed by UV spectroscopy. On the basis of the plot of [P*] vs. time, the rate constant of propagation kp was calculated according to where [M]t’s and [M]e are the instantaneous and equilibrium monomer concentrations, respectively, and ∫t1t2[P*]dt was obtained by graphical integration. It has been concluded that the nature of the promoter does not affect the rate of propagation reaction, although it does affect the overall rate and the initiation reaction. These results support the concept of the promoter’s function, i.e., the promoter is responsible mainly for the formation of propagating species.