Radiation Measurements 42 (2007) 8 – 13 www.elsevier.com/locate/radmeas Structural and optical studies of electron beam-irradiated Makrofol nuclear track detector S.A. Nouh a , ∗ , N. Ibrahim El-Tayeb a , A.F. Said b , M.M. Radwan c , S.A. EL-Fiki a a Physics Department, Faculty of Science, Ain Shams University, Cairo, Egypt b Radiation Physics Department, Nuclear Materials Authority, Cairo, Egypt c Physics Department, Faculty of Engineering in Fayoum, Cairo University, Egypt Received 19 July 2005; accepted 21 March 2006 Abstract The effect of electron beam irradiation on the structural and optical properties of Makrofol solid state nuclear track detector (SSNTD) was investigated. Samples from Makrofol detector were irradiated with electron beam with doses at levels between 10 and 400kGy. Structural and optical property studies using X-ray diffraction, FTIR spectroscopy, color difference measurements and electron paramagnetic resonance were performed on non-irradiated and irradiated Makrofol samples. The transmission of these samples in the wavelength range 200–2500 nm, as well as any color changes, was studied. A characteristic absorption bands with different intensities was observed. Using the transmission data, both the tristimulus and the Commission Internationale de l’Eclairage (CIE) LAB coordinate values were calculated. In addition, the color differences between the non-irradiated sample and those irradiated with different doses were calculated. The results indicate that the Makrofol detector is a material that does not have a high resistance to degradation, and its tendency to crosslinking is much lower than that of several other SSNTDs. © 2006 Elsevier Ltd. All rights reserved. Keywords: Electron beam irradiation; X-ray diffraction; FTIR spectra; Color changes; EPR; SSNTDs 1. Introduction Since radiation is one of the major factors that change the structural properties of polymers, in particular solid state nu- clear track detectors (SSNTDs), it would be worthwhile to study the modifications on their properties due to irradiation (Fromm et al., 2003). Several techniques have been performed on radiation measurements in these SSNTDs and it has been proved that these detectors are good due to their ability to record heavy ionized particles and neutrons (Pugliesi et al., 1999). It is obvious that the primary physical interaction of radiations with these SSNTDs produces specific damage known as chem- ical bond scission, free radicals and consecutive crosslinking (Fromm et al., 2003). Also, passage of heavy ions in these mate- rials creates large-scale lattice defects due to radiation damage ∗ Corresponding author. Tel./Fax: +20 2 2822 189. E-mail address: samirnouh90@hotmail.com (S.A. Nouh). 1350-4487/$ - see front matter © 2006 Elsevier Ltd. All rights reserved. doi:10.1016/j.radmeas.2006.03.010 along the path of the ion which induce formation and transport of reactive species that are able to permanently change the physical and chemical properties of these SSNTDs (Mishra et al., 2003). The effectiveness of these changes produced in SSNTDs depends on the structure of the polymer as well as the experimental conditions of irradiation. Various studies have been performed on the radiation- induced degradation in Makrofol polycarbonate using different kinds of radiations, such as gamma rays (Orlov and Feldman, 2001; Sinha and Dwivedi, 2003; Seguchi et al., 2002), elec- tron beam (Seguchi et al., 2002), neutrons (Ranby and Rabek, 1977) and heavy ions (Ferrain and Legras, 1993). In particu- lar, the degradation induced by gamma rays was intensively studied. The present study deals with the investigation of the effect of electron beam irradiation on the structural and optical prop- erties of Makrofol detector not only to obtain information con- cerning the interaction of electrons with Makrofol, but also to study the feasibility of enhancing its properties, improving its performance in different applications.