Micro and nano Bi2O3 filled epoxy composites: Thermal, mechanical and γ-ray attenuation properties

• Published in: Applied radiation and isotopes Vol. 174; p. 109780
• Main Authors: Muthamma, M.V., Prabhu, Srilakshmi, Bubbly, S.G., Gudennavar, S.B.
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.08.2021
• Subjects: Bismuth oxide; Epoxy; Micro/nano composites; γ-Ray attenuation studies; γ-Ray attenuation studies; Micro/nano composites; Epoxy; Bismuth oxide
• ISSN: 0969-8043; 1872-9800
• DOI: 10.1016/j.apradiso.2021.109780

Polymer composites have attracted considerable attention as potential light-weight and cost-effective materials for radiation shielding and protection. In view of this, the present work focusses on development of lead-free composites of diglycidyl ether of bisphenol A (DGEBA) epoxy resin with micro (~ 10 μm) and nano (~ 20 nm) bismuth (III) oxide (Bi2O3) fillers, using solution casting technique. Thermal, mechanical and γ-ray attenuation properties of the composites were studied by varying the filler loading. Inclusion of the fillers into epoxy matrix was confirmed both structurally and morphologically by XRD and SEM, respectively. Thermogravimetric analysis (TGA) showed the thermal stability of composites to be as high as 400 °C. The nanocomposites exhibited relatively higher thermal stability than their micro counterparts. Among the composites, 14 wt% nano-Bi2O3/epoxy composites showed highest tensile strength of 326 MPa, which is about 38% higher than 30 wt% micro Bi2O3/epoxy composites. Mass attenuation coefficients (μ/ρ) of the composites were evaluated at γ-ray energies ranging from 0.356 to 1.332 MeV. Nanocomposites showed better γ-ray shielding at all energies (0.356, 0.511, 0.662, 1.173, 1.280 and 1.332 MeV) than micro composites with same filler loading. These studies revealed the significance of nano-sized fillers in enhancing overall performance of the composites. •DGEBA epoxy resin based micro and nano-Bi2O3 composites were investigated as potential γ-radiation shielding materials.•A significant enhancement in thermal stability and tensile properties of nanocomposites over micro-composites was observed.•Radio-protective characteristics were evaluated both experimentally and theoretically in the energy range 0.356-1.332 MeV.•14 wt% nano-Bi2O3/epoxy composites showed better shielding performance than 30 wt% micro-Bi2O3/epoxy composites.