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Termination Reaction in the Anionic Polymerization of Methacrylonitrile

F. Ranogajec ; Institute »Ruder Boskovic«, 41000 Zagreb, Croatia, Yugoslavia,
E. V. Kochetov ; Institute of Chemical Physics of the USSR Academy of Sciences, Moscow, USSR
M. A. Markevich ; Institute of Chemical Physics of the USSR Academy of Sciences, Moscow, USSR
N. S. Enikolopyan ; Institute of Chemical Physics of the USSR Academy of Sciences, Moscow, USSR
I. Dvornik ; Institute »Ruder Boskovic«, 41000 Zagreb, Croatia, Yugoslavia,

Sažetak

The anionic polymerization of methacrylonitrile initiated by
triethylphosphine in dimethylformamide was studied. Experimental
evidence for two mechanisms of termination reaction was obtained.
By addition of water or alcohol in polymerizing system the rate of
polymerization and molecular weight of polymethacrylon1itrile
decrease, which proves the termination reaction to be bimolecular
and proceed by interaction of the active carbanion with water or
alcohol. The rate constant for termination of free anions with water
was determined, k~,0 = 2.2 x 102 dm3 moP s-1• The termination
reaction could not be excluded by purification and prolonged drying
of all components of the system, which indicates that the second
mechanism of termination is operative as well. Conductivity measurements gave evidence for a monomolecular spontaneous reaction leading to deactivation of the anion.

Ključne riječi

Hrčak ID:

196821

URI

https://hrcak.srce.hr/196821

Datum izdavanja:

1.11.1974.

Posjeta: 615 *