Nanostructures formation in carbon-filled polymer composites at electron irradiation

Influence of radiation-initiated structure transformations on internal friction temperature dependence and electric resistance in the carbon-filled composites with epoxide binders was studied. Irradiation of composite samples were conducted on the ELU-4 accelerator with energy 2 MeV in the range of absorption doses 0-60 MGy at room temperature. Measurements of internal friction temperature dependence and shift module were conducted on the torsional pendulum at oscillation frequency about 1 Hz in the temperature range 20-300 deg C. It was determined, that the internal friction high-temperature peak (α1-peak) is related with transition of the polymer matrix from glass-like state to high-elastic state. Internal friction low-temperature relaxation maximum is connected with transition of glassing in the boundary fields between the composite layers. Observed correlation of internal friction temperature dependence and electric resistance evidences about current carriers scattering in carbon-filled polymer composites taking place principally on the oscillation of macromolecule' free segments which simultaneously are the elements scattering elastic oscillation energy. At low irradiation doses of electron irradiation (up to 24 MGy) the high growth of electrical resistance and internal friction peaks are observed. The growth related with glassing process due to radiation destruction of the epoxide binder intensively passing in the field of radiation polymer damage. Electron microscopy shows that these field could have micro- and nano-sizes in dependence on radiation dose and electron track over-lab rate. Determined correlation of internal friction temperature dependence clarified the mechanisms of carbon-filled composite conductivity and could be applied in different practical applications of these materials including nano-structure generation with different electric properties on the radiation technological base