Thermal, mechanical and γ‐ray shielding properties of micro‐ and nano‐Ta₂O₅ loaded DGEBA epoxy resin composites

Abstract

In this work, we have investigated the synergistic effect of micro‐ and nano‐Ta2O5 fillers in the epoxy matrix on the thermal, mechanical, and radioprotective properties of the composites. Morphological analysis revealed uniform dispersion of fillers in the matrix. Both the thermal stability and tensile properties of matrices have enhanced in the presence of fillers. Although the nanocomposites showed significantly higher tensile strength and Youngs modulus compared to micro‐composites, the enhancement in these properties was predominant at low loadings. Dynamic mechanical analysis indicated good interfacial adhesion and positive reinforcing effect on the matrix even at higher loading (30 wt%) of nano‐Ta2O5. γ‐Ray attenuation studies performed in the energy range of 0.356–1.332 MeV revealed better γ‐ray shielding ability of nanocomposites compared to microcomposites at same weight fraction of fillers. In particular, γ‐ray attenuation at 0.356 MeV for 30 wt% nano‐Ta2O5 loaded epoxy composite was enhanced by around 13% compared to the microcomposite at the same loading. Increased surface‐to‐volume ratio of nanofillers and consequent increase in matrix‐filler adhesion and radiation‐matter interaction have manifested in an overall enhancement in the thermal, mechanical, dynamic mechanical, and radiation shielding characteristics of nano‐Ta2O5/epoxy composites, proving them as promising γ‐ray shields.

Recent Advances and Challenges in Polymer-Based Materials for Space Radiation Shielding

“…Prabhu et al developed epoxy-based materials filled with micro and nano-tantalum oxide (Ta 2 O 5 ) particles and demonstrated their effectiveness in γ-ray shielding [16]. A diglycidyl ether of bisphenol A (DGEBA) epoxy resin was used as a matrix.…”

“…This behavior can be ascribed to the increase in electron density within the material in the presence of nanoparticles. Similarly, for low-energy gamma rays, smaller, uniformly dispersed particle sizes offer greater photon blocking [16]. However, at higher energies, this effect decreases due to the transition from the photoelectric effect to Compton scattering.…”

“…Compounds like boron carbide (B 4 C) and hexagonal boron nitride (hBN) in nanomaterial form, particularly nano-B 4 C and nano-hBN dispersed in polymer matrix, have demonstrated enhanced thermal neutron attenuation [12]. The positive effect of using nanosized fillers can be related to their surface-to-volume ratio, which increases the interactions with radiation, enhancing the shielding effectiveness [13][14][15][16]. Boron and its low-Z compounds, like B 4 C and hBN, prove suitable for space neutron-shielding applications, while heavier elements are less convenient due to their high atomic weight, leading to fragmentation and the generation of secondary radiation.…”