Speaker
Description
The use of absorbent materials such as hydrogels is of interest to reduce the environmental impact of dyes in industry. These can be polymerized with ionizing radiation and functionalized with materials such as clays with the ability to bind organic and inorganic molecules. Our work group develops hydrogels polymerized with Gamma radiation (60Co), and, as the objective of this study, it was proposed to perform dose distribution simulations using electron beams (E-Beam) in hydrogels. For this, the Dose Uniformity Ratio (DUR) was studied using the PUFFIn® software in hydrogels composed of 5% w/v polyvinyl alcohol, 4% w/v clay, 1% w/v agar, and dimensions (X,Y,Z):(4 cm,4.5 cm,1 cm). The variables set in the software were particle number 1*10+6, beam width and height 10 cm, source distance from product 100 cm. In the simulations E-Beams of different energies (2 MeV, 5 MeV, 7 MeV and 10 MeV), and different source locations (from Y and Z axis) were evaluated. The simulations showed that as energy increases, the penetration of electrons increases. When the source was applied along the Z axis with energy of 5 MeV to 10 MeV the results showed good homogeneity in the dose dispersion, with a low DUR (1.06-1.25). While with 2 MeV+E-Beam from Z, and with hydrogels treated from the Y axis, the DUR was higher, with a range of 4.7-33.12. In these cases, a large dose dispersion is observed, so the cross-linking of the polymers would not be homogeneous and a modification of the dimension, or the rotation of the sample during the irradiation process, should be considered.
In conclusion, in irradiation with E-Beam it is important to consider the geometry of the product, and the location and energy to obtain good dose homogeneity. Also, the PUFFIn® software proved to be a versatile tool that can be used to analyze dose distribution with different irradiation parameters and product geometries useful in industry and research, however, the studies must be confirmed with laboratory tests.
