Study of Gamma-Irradiated Polyamide Using Thermomechanical Spectrometry and Radiothermoluminescence

Resumo

The molecular–topological structure of polyamide before and after γ-irradiation has been first studied by thermomechanical spectrometry. The γ-irradiation with a dose up to 300 kGy does not change the topological structure of the polymer, the four-block pseudo-network structure of which contains crystalline segments of macromolecules and polyassociative entities of the cluster type in addition to low-and high-temperature amorphous blocks. During irradiation, only interblock mass transfer of the chain segments occurs, resulting in different dose-dependent values for the molecular weight of the chains, their weight fraction in each topological block, and the glass transition and molecular flow temperatures of the polymer. Radiothermoluminescence curves exhibit three maxima at 152, 200, and 330 K, of which the last one is detected in a temperature region close to the glass transition temperature of the high-temperature amorphous block on the thermomechanical analysis curve of the polymer.