Page 66 - 00. Complete Version - Progress Report IPEN 2014-2016

66 Application of Ionizing Radiations | Progress Report

column was analyzed using high performance
liquid chromatography (HPLC) in order to in-
vestigate chemical phase diffusion of bisphe-
nol A (BPA). EPR results showed strong singlet
attributed to phenoxyl radical, which decays
within 40 days. UV spectra presented increase
in relative absorbance at 400-450nm with in-
creasing radiation absorbed dose. Ionizing ra-
diation caused greenness of original clear PC
samples. On the other hand, glass transition
temperature decreased 1% (5K) for maximum
Figure 30. 99Mo/99mTc generator columns: a) applied radiation dose. Similarly, small de-
borosilicate type 1 glass; b) polycarbonate PC.
crease on carboxyl group peak at 1770 cm-1
was observed by FTIR. No detectable change
thesized copolymers with various graft ratios on crystallinity was observed by WAXD. HPLC
were characterized by ATR-FTIR spectroscopy, with fluorescence detector can be employed
X-ray photoelectron spectroscopy (XPS), ther- to analyze chemical phase diffusion of BPA in
mal analysis and scanning electron microsco- saline solution at ppb concentration. For ster-
py (SEM). Cumyl dithiobenzoate (CDB) mediat- ilization absorbed dose, no significant chang-
ed RAFT polymerization of GMA revealed the es on studied properties was observed, that
difficulty of controlling the polymerization of way it can be recommended to use PC instead
GMA due to high crosslinking tendency of this of borosilicate glass column in 99Mo/99mTc
monomer under ε-irradiation. generator.

Polycarbonate chromatography column to be Recycling Polymers by Irradiation Process
used in a 99Mo/99mTc generator irradiated in
saline solution with electron beam and gamma
rays 99Mo/99mTc generator is a device used
to extract the 99mTc of decaying 99Mo. Cur-
rently, chromatographic column of acid alu-
mina (Al2O3), principal component of gener-
ator, is made of borosilicate type 1 glass. The
goal of this study was to characterize irradiat-
ed polycarbonate (PC) column in saline solu-
tion to mimic a 99Mo/99mTc generator in real
condition of use. PC column and samples were Figure 31. Injected HDPE samples: 1) virgin; 2) Recycled (20 times by
extrusion); 3) , 4), 5) and 6) composites with EPDM rubber in distinct
electron beam and gamma irradiated in saline concentrations respectively 1% and 5 % nonthermal treated, 5 %
solution with radiation absorbed doses up to thermal treated (composites with virgin and 20 x recycled HDPE).
200 kGy. Samples were analyzed by electron
paramagnetic resonance (EPR), infrared (FTIR),
ultraviolet (UV) spectroscopies, differential High density polyethylene (HDPE) and eth-
scanning calorimetry (DSC) and wide-angle ylene-propylene-diene monomer rubber
X-ray diffraction (WAXD). Additionally, saline (EPDMR) were recycled to obtain blends and
solution gamma irradiated in presence of PC composites for several applications. Some char-

Instituto de Pesquisas Energéticas e Nucleares