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The induced alterations in the structure and thermal properties of polyaniline-cobalt/polycarbonate, PANI-Co/PC, nanocomposite (NCP) owing to  irradiation have been investigated. The chemical composition and morphology of the prepared NCP samples were studied using scanning electron microscopy and energy dispersive spectrometry technique. Additionally, X-ray diffraction (XRD), FTIR spectroscopy, thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were performed to investigate the resulted effect of  radiation. The  radiation with doses 50-350 kGy leads to the prevalence of intermolecular crosslinking which enhances the disordered phase and increases the bonds between the hydrogen of the PANI amine groups and carbonyl groups of PC. This is reflected in a rise in the degradation temperature values from 400 to 475oC indicating an improvement in the thermostability of the NCP samples. Additionally, the melting temperature increased from 350 to 361 oC indicating a more compact structure of the NCP samples.

The aim of the present study was extended from obtaining information about the interaction of gamma rays with Makrofol DE 7-2 track detector to introduce the basis that can be used in concerning simple sensor for gamma irradiation and bio-engineering applications. Makrofol polymer samples were irradiated with 1.25MeV 60Co gamma radiations at doses ranging from 20 to 1000kGy. The modifications of irradiated samples so induced were analyzed using UV–vis spectrometry, photoluminescence spectroscopy, and the measurements of Vickers’ hardness. Moreover, the change in wettability of irradiated Makrofol was investigated by the contact angle determination of the distilled water. UV–vis spectroscopy shows a noticeable decrease in the energy band gap due to gamma irradiation. This decrease could be attributed to the appearance of a shift to UV spectra toward higher wavelength region after irradiation. Photoluminescence spectra reveal a remarkable change in the integrated photoluminescence intensity with increasing gamma doses, which may be resulted from some matrix disorder through the creation of some defected states in the irradiated polymer. The hardness was found to increase from 4.78MPa for the unirradiated sample to 23.67MPa for the highest gamma dose. The contact angle investigations show that the wettability of the modified samples increases with increasing the gamma doses. The result obtained from present investigation furnishes evidence that the gamma irradiations are a successful technique to modify the Makrofol DE 7-2 polymer properties to use it in suitable applications.

Bayfol CR 1-4 is one of polymeric solid state nuclear track detector which has numerous applications due to its outstanding optical, mechanical, thermal and electrical properties. In the present study, Bayfol polymer is irradiated with different doses of gamma rays ranging from 0 to 1000 KGy. The effects of gamma irradiations on the optical, structural and chemical properties of Bayfol were studied using Ultraviolet and visible (UV/Vis) spectroscopy, X-ray diffraction (XRD) and Fourier transform infrared (FTIR) spectroscopy. The UV–Vis spectra of irradiated samples show that the absorption edge is shifted towards longer wavelength comparing to pristine sample spectrum. This behavior indicates that there is a decrease in the band gap after irradiation. The maximum decrease in the band gap is about 0.8 eV. The XRD patterns of amorphous halo of pristine and irradiated samples show a fluctuation of integrated intensity of amorphous halo. This indicates a change in the structure due to gamma irradiation. In order to understand that structure change mechanism, we used the FTIR spectroscopy.

The effects of ion-beam bombardment on the physical and chemical properties of poly(allyl diglycol carbonate) (CR-39) polymer have been investigated. CR-39 samples were bombarded with 320 keV Ar and 130 keV He ions at fluences ranging from 1 × 1013 to 2 × 1016 ions/cm2. The nature and extent of radiation damage induced were studied by UV–VIS spectrometry, Fourier-transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD) analysis, as well as Vickers' hardness measurements. In addition, the effect of ion fluence on the wetting properties of ion-beam bombarded CR-39 polymer was determined by measuring the contact angle for distilled water. UV–VIS spectra of bombarded samples reveal that the optical band gap decreases with increasing ion fluence for both Ar and He ions. In the FTIR spectra, changes in the intensity of the bands on irradiation relative to pristine samples occurred with the appearance of new bands. XRD analyses showed that the degree of ordering of the CR-39 polymer is dependent on the io...

Ion bombardment is thought to have great potential for improving the optical properties of polymeric materials. In this paper, Poly-Allyl-Diglycol-Carbonate (CR-39) polymer samples were bombarded with 320 keV Ar and 130 keV He ions, at different ion fluences. Effects of ion bombardment on the optical properties of CR-39 have been investigated using UV–vis spectrophotometer and photoluminescence (PL) spectroscopy. UV–vis spectra of irradiated samples reveal that the optical band gap decreases with increasing the ion fluence for both Ar and He ions. The width of the tail of localized states in the band gap ( E u ) was evaluated using the Urbach edge method. The decrease in the PL intensity with the increase in the ion fluence was observed. This decrease is attributed to ion bombardment induced defects and clusters in the CR-39 which serves as non-radiative centers.

Measurements of the neutron doses in and around its sources are important for the purpose of personal and environmental neutron dosimetry. In the present work, we investigate a method for the measurement of neutron dose using the ultraviolet–visible (UV–VIS) spectra of an irradiated CR-39 plastic track detector. Therefore, a set of CR-39 plastic detectors was exposed to a source of fast neutrons, which has a yield of 0.68×108 s−1, and the neutron equivalent dose rate 1 m apart from the source is equal to 0.038 mSv/h. The samples were etched for 10 h in 6.25 N NaOH at 70±0.1 °C. Using the UV method, changes in the UV–VIS spectra of CR-39 with different neutron doses were obtained and the absorbance of the etched samples was measured using a UV–VIS spectrophotometer as a function of neutron dose. Further, it is observed that there is a linear relationship between the optical absorption of these detectors and neutron doses. Hence, the linear graph can be used as a calibration to measure the unknown dose of n...

The results of an experimental work aimed at improving the performance of the CR-39 nuclear track detector for neutron dosimetry applications are reported. A set of CR-39 plastic detectors was exposed to 252 Cf neutron source, which has the emission rate of 0.68 × 10 8 s −1 , and neutron dose equivalent rate 1 m apart from the source is equal to 3.8 mrem/h. The detection of fast neutrons performed with CR-39 detector foils, subsequent chemical etching and evaluation of the etched tracks by an automatic track counting system was studied. It is found that the track density increases with the increase of neutron dose and etching time. The track density in the detector is directly proportional to the neutron fluence producing the recoil tracks, provided the track density is in the countable range. This fact plays an important role in determining the equivalent dose in the field of neutron dosimetry. These results are compared with previous work. It is found that our results are in good agreement with their investigations.

The thickness of the removed layer of the LR-115-II solid state nuclear track detector during etching is measured directly with a rather precise instrument. Dependence of bulk etching rate on temperature of the etching solution is investigated. It has been found that the bulk etching rate is 3.2 µm/h at 60°C in 2.5 N NaOH of water solution. It is also found that the track density in detectors exposed to soil samples increases linearly with the removed layer.

An alpha track was selected through a number of successive CR-39 sheets in a high energy nuclear reaction experiment. The experiment was aimed at identifying particles emitted at an angle of 25° to the beam direction when bombarding a copper disk with relativistic fluorine ions. Most of these particles were identified as protons and alpha particles. The experiment showed that the inlet energy of an alpha particle to be detectable in CR-39 plastic is 53.4 MeV per nucleon. The CR-39 range of such particles is ∼2 cm long. The corresponding range for a proton is ∼1 mm long. The track diameter at positions on the track length can display the damage as a function of the depth in the CR-39 material. In addition, the track length is measured along the particle trajectories in CR-39 sheets for a single track as a function of residual range in the CR-39 material. The restricted energy loss (REL) for alpha tracks in CR-39 is calculated using the Henke–Benton computer program. Comparison between the REL and the damag...

The formation of etched tracks in solid-state nuclear track detectors is usually described by assuming an unequivocal correlation of the etch-rate ratio with the energy loss of charged particles. For alpha particles, this assumption could be verified within the scatter of the experimental data. In this article, the dependence of the depth (x) on the track etch rate (V T) was determined experimentally by track length measurement. It is found that the track etch rate as a function of the depth within the detector follows the Bragg curve. The track etch rate has been found to be described by a generalization of the restricted energy loss, in good approximation along the trajectories of alpha particles.