Effect of Electron Irradiation on Internal Friction and Molecular Structural Alterations in Polymer-Based Composite Materials Reinforced with Mica and Asbestos
Yu.A. Zaikin and N.A. Shirokaya
Science Research Institute of Experimental
& Theoretical Physics, al-Farabi Kazakh National
Effect of electron irradiation on temperature dependences of internal friction in polymer-based composites armored with mica and asbestos is studied. Characteristics of mechanical relaxation spectra and radiation-initiated molecular structural alterations in this type of composites are discussed. It is shown that structural alterations after composite irradiation depend not only on the irradiation dose but to the great extent on the dose rate. In the scissoring polymers at the absence of track and spur overlapping, increase in the dose rate causes the higher degree of polymer radiation scission at the same irradiation dose. At the values of dose and dose rate that exceed the level characteristic for the given type of the polymer binder, spur overlap leads to the decrease in the relative rate of radiation scissoring. The latter can be the cause of the scissoring change to cross-linking at heightened doses and dose rates. All the polymer binders used in the composites under study are subjected to destruction at the heightened doses of electron irradiation. Thermal processing of this type of composites can be used both for their higher radiation resistance and partial recovery of the cross-linked structure of their polymer matrix.