Preparation, characterization and X-ray attenuation property of Gd2O3-based nanocomposites

Abstract

In an attempt to develop an alternate to leadbased X-ray shielding material, we describe the X-ray attenuation property of nanocomposites containing Gd 2 O 3 as nanofiller and silicone resin as matrix, prepared by a simple solution-casting technique. Gd 2 O 3 nanoparticles of size 30 and 56 nm are used at concentrations of 25 and 2.5 wt%. The nanoparticles and the nanocomposites are characterized using X-ray diffraction (XRD) studies, small angle X-ray spectroscopy (SAXS), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and atomic force microscopy (AFM). The X-ray attenuation property of nanocomposites, studied using an industrial X-ray unit, shows that nanocomposites containing nanoparticles of size 56 nm (G2) exhibit better attenuation than nanocomposites containing nanoparticles of size 30 nm (G1), which is attributed to the greater interfacial interaction between the G2 nanofillers and silicone matrix. In the case of nanocomposites containing G1 nanoparticles, the interfacial interaction between the nanofiller and the matrix is so weak that it results in pulling out of nanofillers, causing voids in the matrix, which act as X-ray transparent region, thereby reducing the overall X-ray attenuation property of G1 nanocomposites. This is further corroborated from the AFM images of the nanocomposites. The weight loss and heat flow curves of pure silicone matrix and the nanocomposites containing Gd 2 O 3 nanoparticles of size 30 and 56 nm show the degradation of silicone resin, due to chain scission, between 403 and 622°C. The same onset temperature (403°C) of degradation of matrix with and without nanoparticles shows that the addition of nanofillers to the matrix does not deteriorate the thermal stability of the matrix. This confirms the thermal stability of nanocomposites. Therefore, our study shows that nanocomposites containing G2 nanoparticles are potential candidates for the development of X-ray opaque fabric material.

Multifiller nanocomposites containing gadolinium oxide and bismuth nanoparticles with enhanced X‐ray attenuation property

“…The average crystallite size of the nanoparticles was analyzed using X-ray diffraction studies. 16,25 A two-component room temperature vulcanized (RTV) silicone polymer with a mixing ratio (Part A: Part B) of 100:5 (S1, density:~1.7 g/cm 3 ) (Make: Anabond) was used as the polymer matrix. The two-component RTV silicone polymer used in this study consists of hydroxy capped dimethylsiloxane polymer (base) with a molecular weight of 400-600 kDa (Part-A) and methyltriacetoxysilane as the curing agent with dialkyltin as the catalyst (Part-B).…”

“…Multifiller nanocomposites were prepared using a simple solution casting technique, with the nanofillers in different combinations, as discussed extensively in our previous studies. 16,25,46 Detailed information on the nomenclature and composition of the nanocomposites is given in Table 1. X-ray attenuation properties of the prepared nanocomposites were studied using a 200 MF X-ray unit (Eresco Rich-Seifert), with a focal spot size of 1.5 mm.…”

“…The average surface roughness was obtained from AFM topography images using simple statistics. 25 The surface morphology of the nanocomposites was analyzed using a field emission scanning electron microscope (FESEM, Gemini, M/s Zeiss, Germany). Energy dispersive X-ray spectroscopy (EDAX), coupled with FESEM, was performed to analyze the chemical composition of the nanocomposites before and after X-ray irradiation.…”

“…In addition to the nanocomposites discussed under section 2.1, several other nanocomposites of α-Bi 2 O 3 (Make: Alfa Aesar, 80 nm), octyl silane functionalized silica (Make: PlasmaChem, 7-14 nm), graphene (Make: PlasmaChem, thickness: 1-4 nm; size: upto 200 μm) and multiwalled carbon nanotubes (MWCNT) (Make: Otto Chemie, outer diameter: 8-20 nm; length: 5-15 μm) were also examined under clinical conditions and compared with nanocomposites discussed in the above section. 16,25,46,49 A complete description of nanocomposites studied here is given in Table 1.…”

“…20,23,24 The diagnostic X-ray attenuation property of polymer nanocomposite containing single nanofiller, such as, bismuth, bismuth oxide, and gadolinium oxide is studied previously. 6,10,16,25 Dejangah et al, have studied the X-ray attenuation and mechanical properties of room temperature vulcanized silicone polymer containing tungsten. 26 Similarly, Gungor et al, have discussed the mechanical, thermal and X-ray attenuation properties of ethylene propylene diene monomer rubber containing bismuth trioxide nanofillers.…”