Studium der lebenden radikalischen Polymerisation mit der Differential Scanning Calorimetry (DSC)

The living radical polymerization of styrene, some styrene-analogous vinyl monomers as well as methyl methacrylate (MMA) and butyl methacrylate (BuMA) was investigated with a differential scanning calorimeter. The ability to polymerize was estimated by dynamic measurements, showing that p-methylstyrene, p-chlorostyrene, 3,4-dimethoxystyrene and 4-vinylpyridine polymerize in the presence of 2,2,6,6-tetramethyl-1-piperidine-N-oxyl (TEMPO) while MMA and BuMA do not. Isothermal measurements revealed an activation energy of E A = 81 kJ mol -1 for thermal bulk polymerization of styrene and values of E A = 78-94 kJ mol -1 were measured with different iniferter systems. These polymerizations have induction times which depend on the reaction temperature and the initial concentration of the iniferter systems. An influence of the kind of nitroxyl radical on the induction times was not observed.