Termination of ionic polymerizations

Under certain stringent conditions, all ion reactivity is concentrated on propagation. The resulting polymerizations are living. In other cases, the instability of the ions is manifested by a complex of poorly defined reactions leading to transfers, retardation, and decay of the polymerizing activity of the centres, i.e. termination. Termination is either an inherent feature of the respective polymerizing system or it may be caused by accidental impurities or, finally, it may be a consequence of deliberately added compounds. 

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