Polymethylene Intermediates in Thermal and Photoinduced "Charge-Transfer" Polymerization

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The bond - forming initiation theory proposes that the tetramethylene intermediates, encountered in the cycloaddition reaction of electron-rich with electron-poor olefins, are also the true initiators for the spontaneous polymerizations observed in these systems. Zwitterionic intermediates initiate ionic homopolymerization of either donor and/or acceptor olefin, while diradical intermediates initiate the radical copolymerization. In previous phases of this project, this hypothesis has been proven for a zwitterionic and for a diradical systems. This theory is now being extended to reactions of electron- rich dienes with electron-poor olefins. It is proposed that the spontaneous polymerizations which occur in many of these systems are initiated by a hexamethylene intermediate, which can be either zwitterionic or diradical. In analogy with the thermal reactions, the theory will also be extended to photoinduced polymerization in electron-rich and electron-poor olefin systems. Here again, it is proposed that a tetramethylene intermediate, zwitterionic or diradical, is the initiator of the observed polymerizations.