Polymerization kinetics, radiation during

Bruk et al. [716] described the low-temperature radiation polymerization of crystalline TFE in detail. It has been established that three solid-phase postpolymerization reactions can take place when irradiated specimens are heated above the melting point low-temperature polymerization (in the interval 77 to IlOK), slow polymerization close to the melting point (in the interval 128 to 138 K), and rapid polymerization during melting of the crystal (142 K). Tabata et al. [717] have found that a significant post-polymerization takes place even in the liquid phase. Kinetic analysis has been made of the in-source and post-polymerizations [718,719]. Post-polymerization is explained by a long lifetime of polymer radicals in the hquid phase at —78 °C due to the slow combination rate of the polymer radicals caused by their rod-like shape. 

These defects existed in the same geometry in the monomer and polymer crystal and hence are frozen in during the radiopolymerization process. There was no visual evidence of enhanced polymerization in the vicinity of these defects or of dislocation multiplication. This apparent lack of enhanced reactivity at dislocations to high energy radiation was confirmed in kinetic studies of the y-ray induced process. 

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