Total Ionizing Dose X-ray Radiation Effects on MWCNT/PMMA Thin Film Composites

Multiwalled carbon nanotube (MWCNT) and poly(methyl methacrylate) (PMMA) composites are a new class of nanomaterial composites that have potential to be deployed as sensing elements for various applications including ionizing radiation detection. In this paper, we present an investigation of the ionizing radiation effects on electrical resistance of this composite both from a dose and dose rate standpoint. The solution blending method was used in synthesizing the MWCNT/PMMA composites. The synthesized thin film composites were cast on an interdigitated electrode to perform radiation sensing experiments. A 160-kV X-ray radiation source was used to study the ionizing radiation effects on the synthesized composite. A carbon black/PMMA composite was synthesized and subjected to the same dose and dose rate experiments as the MWCNT/PMMA thin film composite and a comparison was made. We have observed a very good repeatable quasi-linear response curve for radiation dose and dose rate measurement with the MWCNT/PMMA composite. Post radiation exposure recovery time of MWCNT/PMMA composite and heat treatment technique to accelerate recovery time have also been studied and the results are presented. The results suggest that simple sensor elements based on relatively economical MWCNT may be useful for the detection of ionizing radiation.