Frequency dependence of the electrical conductivity and dielectric constants of polycarbonate (Makrofol-E) film under the effects of γ-radiation

Abstract

Irradiation effects of γ-radiation on the physical and electrical properties of polycarbonate (Makrofol-E) film has been studied to be able to investigate the dielectric response of irradiated polymers for a wide range of fluence and frequency. The dielectric constant (ε') The loss tangent (tanδ), dielectric loss factor (ε''), the a.c electrical conductivity (σ) and the relaxation time (τ), were measured in the frequency range from (40) Hz to (4) MHz. These samples were irradiated by means of γ-rays from 10 up to 200 KGy. The change in different properties as a function of absorbed dose was studied. Degradation of the polymers leading to amorphisation was observed by increasing the absorbed γdose. The induced changes in the electrical conductivity due to γ-rays irradiation of Makrofol-E provide a better method for γ-dose measurements. A semi-empirical equation was developed to use Makrofol-E as a dielectric dosimeter. Furthermore, Makrofol-E has much greater resistance to radiation damage; the attained results suggested strongly the applicability of Makrofol-E to be used in medical products applications.

Biosilica Properties from Rice Husk using Various HCl Concentrations and Frequency Sources

“…This factor causes a drop in the net polarization of the material as each polarisation mechanism ceases to contribute, and hence its dielectric constant will drop. Fares [32] pointed out that the motion of free charge carriers is constant at a lower frequency so that the dielectric constant is constant. As the frequency increases, the charge carriers move through the dielectric and get trapped at the defect site which is causing opposite charges in the vicinity.…”

Electrical and optical properties of Makrofol DE 1-1 polymeric films induced by gamma irradiation

“…Irradiated polymeric materials with ionizing radiation such as γ-rays, X-rays, accelerated electrons, and ion beams leads to the formation of very reactive intermediates products like excited states, ions, and free radicals, which result in rearrangements and/or formation of new bonds. The effects of these reactions lead to the formation of oxidized products, grafts, scission of main chain (degradation), or cross-linking beside its effects on the optical, thermal, and electrical behavior of such polymer (Zahran et al 1981;Saad et al 2014;Fares 2011;Tayel et al 2015;Rammah 2015Rammah , 2017Al-Amri et al 2017;Alfaramawi et al 2017;Alsalhi et al 2017;Jaleh et al 2017;Rammah and Abdalla 2017;Saad et al 2018;Abdul-Kader et al 2018). Degradation and cross-linking occur simultaneously, and the outcome of the process is determined by a competition between the reactions (Kumar et al 2006;Sinha et al 2004).…”

“…Polycarbonate detectors are used as a particle track detector for neutrons and alpha particles (Nouh et al 2004;Price 2005;Awad et al 2007;Awad et al 2008;. Moreover, radiation effects on dielectric properties are of particular interest to science and technology and they have many applications in modern engineering (Basha et al 1996;Ahmed et al 2001;Kecskemeti et al 2006;Hanafy 2008), and the effect of ion irradiation on the dielectric properties of polymers has been also studied earlier (Yoshida et al 1980;Chailan et al 1997;Martinez-Pardoma et al 1998;Phukan et al 1999;Fares 2011).…”

Диэлектрические Потери В Насыщенном Водородом Титане Вт1-0 При Распространении В Нем Вихревых Токов

“…Подчеркнем, что тангенс угла диэлектрических потерь образца титана без водорода не содержит пиковых значений. Именно содержание водорода как " примеси" в исследуемом образце влияет на значение потерь [11][12][13]. Подчеркнем, что для образцов с различным содержанием водорода изменяется не только пиковое положение значений диэлектрических потерь, но и величина максимума пика.…”