Untersuchungen zur Gegenionenstruktur bei der Kationischen Polymerisation von Isobutylvinylether mit iodhaltigen Initiatoren

Investigations on the Counter Ion Structure of the Cationics Polymerization of Isobutylvinylether with Iodine Based Systems The structure of counter ions of iodine based initiators for the cationic polymerization of isobutylvinylether is elucidated by means of u.v.-spectroscopy using as model system: Increasing electrophilicity of the cation causes a decrease of the counter ion stability. High concentrations of iodine lead to the formation of polyiodides, as I and I, respectively. The influence on chain propagation by iodine and monomer concentration as well have been followed by GPC and u.v.-spectroscopy. Both influences, strongly affects the propagation reaction. Triphenylmethylbromide in conjunction with iodine is a convenient initiating system, realizing a long living and transfer suppressed propagation, when solvents of higher polarity are used. An activated carbon-halide bond is concluded to be the active species.