The fabrication of different weight percentages of Polycarbonate-Bismuth Oxide composite (PC-Bi2O3), namely 0, 5, 10, 20, 30, 40, and 50 wt%, was done via the mixed-solution method. The dispersion state of the inclusions into the polymeric matrix was studied through XRD and SEM analyses. Also, TGA and DTA analyses were carried out to investigate the thermal properties of the samples. Results showed that increasing the amount of Bi2O3 into the polymer matrix shifted the glass transition temperature of the composites towards the lower temperatures. Then, the amount of mass attenuation coefficients of the samples were measured using a CsI(Tl) detector for different gamma rays of 241Am, 57Co, 99mTc, and 133Ba radioactive sources. It was obtained that increasing the concentration of the Bi2O3 fillers in the polycarbonate matrix resulted in increasing the attenuation coefficients of the composites significantly. The attenuation coefficient was enhanced twenty-three times for 50 wt% composite in 59 keV energy, comparing to the pure polycarbonate.

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In this research, for the first time, the polycarbonate/bismuth oxide (PC–Bi2O3) composite was studied as a beta-ray sensor using a pure beta-emitter 90Sr source. Firstly, the range and stopping power of the electrons in the composite at various loadings of 0, 10, 20, 30, 40, and 50 wt% were calculated using the ESTAR program. Results of simulation demonstrated that the concentration of the heavy metal oxide particles into the polymer matrix played an important role in evaluating the range and stopping power of the electrons in the composite. Secondly, at the experimental phase, the pure Polycarbonate and 50 wt% PC–Bi2O3 nanocomposite with dimensions of 4 × 4 × 0.1 cm3 were prepared and irradiated by 90Sr. Also, current–voltage (I–V) plot exhibited linear response ranging from 100 to 1000 V at the fixed source‐to‐surface distance (SSD). Then the amount of electric current as the sensor response was measured in various dose rates at the fixed voltage of 400 V for the pure Polycarbonate and 50 wt% PC–Bi2O3 nanocomposite using an electrometer, in which results showed that the sensitivities were found as 20.3, and 33.3 nC mSv−1 cm−3, respectively. This study showed that this composite could serve as a novel beta-ray sensor.

In this research work, a two-dimensional model to predict the electrical percolation threshold (EPT) of the polymer/graphene-based nanocomposites in different concentrations of the randomly dispersed inclusions in various polymer matrices is introduced using the finite element method (FEM). The predicted EPT values were validated by other experimental results for different nanocomposites. Results showed that the electrical conductivity of different nanocomposites is significantly related to the percentage weight of the reinforcing phase in the polymer matrix. Furthermore, the addition of graphene-based nano-fillers in the polymer matrix caused a decrease in the tunneling distance in nanocomposites.