Characterization of conducting polymer composites and non-conducting polymers with exposure of neutrons, gamma rays & charged particles

Abstract

Irradiation induced modification in polymeric materials is an active area of research from the scientific and technological perspective. When an ionizing radiation passes through a polymer, the incident energy is transferred to the medium as a result of primary ionization and excitation of the target molecules. Charged particles lose their energy to the stopping materials, mainly via two independent processes i.e. elastic collisions (ion atom interaction) and inelastic collisions (ion electron interaction). The former is the dominant mechanism at low energies region (~keV/nucleon), whereas the inelastic collisions dominant at high energies (gt1MeV/nucleon). Thus, for heavy ions the electronic energy loss leads to the deposition of incident energy on the target material, which creates defects and atomic displacement due to the formation of tracks in terms of cylindrical zones of the order of some nanometers in diameter in the material. newlineIrradiation induces bond breaking, main chain scission, creation of unsaturated bonds, intermolecular cross linking, radical formation and loss of volatile fragments. All these processes are responsible for the modification of chemical, electrical, optical and mechanical properties of polymers leading to their applications in different scientific and technological fields viz. microelectronics, sensors, dosimetry, catalysis, lightemitting diodes, electromagnetic interference shielding, super capacitors and so on. The effectiveness of these transformations produced in the polymeric materials predominantly depends on the structure and the ion beam parameters such as ion energy, linear energy transfer, fluence/dose, mass, charge etc. and the nature of the target material itself. It is obvious from literature survey that a systematic study of the effects of irradiation on the properties of polymeric materials is needed to check the role of radiation agents in the modification process.