CYCLOPOLYMERIZATION.

Abstract

Definition of functionality of monomers and theoretical considerations of cyclopolymerization are followed by a presentation of polymerization study diallylamines. It is shown that diallylamines readily undergo free-radical polymerization to form polymers which contain cyclic structures. Five-membered rings predominate, and this conclusion is supported by ESR spectroscopy of the radicals formed in a flow system, by chemical characterization of the compounds formed under nonpropagating conditions, and by NMR spectroscopy of the polymers. The presence of substituent groups in the diallylamine molecule has an important bearing on the cyclization reaction. From a theoretical viewpoint, the formation of the 5-membered ring structure indicates that the generally accepted less stable primary radical is formed in preference to the 6-membered structure which would contain a secondary radical. This apparent conflict is explained by the kinetics of the reaction and particularly the stereo-electronic effects which operate in the transition state.