The inhibiting action of ketones in the cationic polymerization of β-propiolactone

Autor: G.S. Sanina, Ye.B. Lyudvig, A.K. Khomyakov
Rok vydání: 1974
Předmět:
Zdroj: Polymer Science U.S.S.R.. 16:924-930
ISSN: 0032-3950
DOI: 10.1016/0032-3950(74)90200-7
Popis: It is shown that in the cationic polymerization of β-propiolactone the introduction of ketones into a system leads to a bimolecular chain termination reaction. Kinetically this is reflected in a deviation of the reaction rate from first order with respect to monomer, and in the reaching of a limit before consumption of the monomer has been completed. The change in the rate in the course of the process is described by the equation lnυM = lnkpCK1M0 − ktBK1M0 t and the maximum yields of polymer γ are related to the ketone concentration B by the expression: 1n (1−γ)= −kpcktB. The rations of the termination rate constants kt to the equilibrium constants for the nine ketones studied were determined in the light of the kinetic data. It is shown that these ratios are greatly influenced by the structures of the ketones.
Databáze: OpenAIRE