Radical thermo- and sonopolymerization of methyl methacrylate initiated byiodobenzene 1,1-diacetate

The efficiency of iodobenzene 1,1-diacetate or (diacetoxyiodo)benzene (DAIB ) as a thermo- and sono-initiator of methyl methacrylate (MMA) in radical b ulk polymerization is tested. The polymerization kinetics and molecular-mas s characteristics support an assumption for a combined polymerization mecha nism including a classical bimolecular termination with chain transfer reac tion and iniferter quasi-living polymerization. In addition to the equilibr ium formation and degradation of the 'dormant' polymer ends, other possible decomposition reactions of the hypervalent iodine bond are the probable re ason for the deviation of this polymerization from the iniferter polymeriza tion mechanism. These reactions bear some similarity to the two-step additi on-fragmentation chain transfer mechanism of controlled radical polymerizat ion. The application of the poly(MMA) obtained as a macroinitiator is evide nce of 'dormant' chain end formation. (C) 2001 Society of Chemical Industry .