Physical, morphological and dosimetric characterization of the Teflon agglutinator to thermoluminescent dosimetry

In preparing of thermoluminescent dosimeters (TLD) it is common to use as agglutinator the polytetrafluoroethylene (PTFE), called Teflon (R). In this paper the physical, morphological and dosimetric characteristics of Teflon (R) were evaluated aiming its application in thermoluminescent dosimetry. The differential thermal analysis (DTA) and thermogravimetry (TG) results showed that the Teflon glass transition and melting points are of about 48 degrees C and 340 degrees C, respectively. By means of the X-ray diffraction technique, the crystallinity index K-c was estimated as 94%. Micrographs of Scanning Electron Microscopy (SEM) showed a cohesive surface in spodumene-Teflon pellets, as required for thermoluminescent dosimeters (TLD), leading to the conclusion that Teflon acts as binder, providing greater mechanical resistance to the TL pellets. However, Teflon may influence high doses dosimetry when it is applied as an agglutinator. Preliminary results of Teflon pellets dosimetric properties, with their dose-response curve between 50 Gy and 60 kGy, TL response reproducibility and minimum detectable dose, indicate the possibility of use of pure Teflon TLD in high-dose dosimetry. (C) 2012 Elsevier B.V. All rights reserved.