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Silicone polymer‐based nanocomposites containing β‐Bi2O3 nanoparticles with varying concentrations of silica nanoparticles are successfully prepared and characterized for thermal stability, surface topography, and X‐ray attenuation property. Of all the samples studied here, silicone polymer of higher density (S1) containing β‐Bi2O3 (50 wt%) and silica (0.025 wt%) nanoparticles is found to be thermally stable upto 424 and 375°C in argon and oxygen atmosphere, respectively. The atomic force microscopy image of top and cleaved surface of this nanocomposite exhibits an average roughness of 12 and 506 nm, respectively. It also exhibits the highest X‐ray attenuation property, among the samples analyzed here, against X‐rays of energies in the range of 30–66 keV. Therefore, S1 silicone polymer containing β‐Bi2O3 and silica (0.025 wt%) nanoparticles is a potential material for the development of lead‐free and X‐ray opaque aprons, gloves, thyroid collar, gonad shield, and so on. [ABSTRACT FROM AUTHOR]

We report, here, the corrosion inhibition of mild steel specimen in 1 M HCl by tamarind fruit pulp aqueous (TFPA) extract. The inhibition property in the presence of TFPA extract is studied using weight loss, polarization measurement and electrochemical impedance spectroscopy (EIS). The inhibitor efficiency is found to vary from 74% to 88% (weight loss method) with TFPA concentration of 100–600 ppm. The reduction in Tafel slopes shows that TFPA acts as a mixed-type inhibitor. The adsorption of the inhibitor on the metal surface follows Langmuir isotherm. The standard Gibbs free energy of adsorption value of –40 kJ/mol suggests the chemisorption of inhibitor molecules via coordinate bond. AFM results exhibit a decrease in the surface roughness of mild steel, exposed to 1 M HCl from 299 ± 12 to 154 ± 6.6 nm, with increasing concentration of inhibitor from 0 to 600 ppm due to the uniform coverage of inhibitor molecules on the metal surface. X-ray photoelectron spectroscopy de-convoluted high resolution profiles of C 1 s (carbon) for mild steel exposed to 1 M HCl with 600 ppm inhibitor show major peaks corresponding to sp3 C–C/C–H (284.9 eV) and oxygen bondings in C–OH, C=O, COOH with a binding energy of 285.9, 286.9, 288.5 eV, respectively, thereby confirming the adsorption of organic moieties on mild steel surface. Fourier transform infrared spectroscopy further confirms the adsorption of inhibitor molecules on the metal surface. Therefore, tamarind fruit pulp extract is a potential corrosion inhibitor for mild steel, which is cost-effective, green and non-toxic. [ABSTRACT FROM AUTHOR]

The prolonged exposure of high-energy ionizing radiations during treatment of cancer/tumour and radiological examinations is hazardous to occupational workers and patients. Lead-incorporated composite materials are traditionally used as radiopaque fabrics, but are heavy, bulky and hence often cause inconvenience to users. Therefore, superior radiopaque protective wears that are preferably lead-free, light weight and flexible are being explored. Towards this goal, we study here the synergistic effect of graphene nanoplatelets and multi-walled carbon nanotube (MWCNT) on the X-ray attenuation property of polymer nanocomposites containing β-Bi2O3 nanofillers. The effect of graphene and MWCNT at different concentrations on Bi2O3-based polymer nanocomposites is studied to attain optimal compositions with respect to its X-ray attenuation property and thermal stability. Surface topography and surface roughness of the nanocomposite blocks are studied using an atomic force microscope (AFM). The effect of the density of polymer on the curing, thermal stability and X-ray attenuation property is also studied by using silicone polymers of density 1.7 (G1) and 1.04 g/cm3 (G2). The X-ray attenuation property of nanocomposites with G1 polymer matrix is found to be better than that of G2. The G1-based nanocomposite containing β-Bi2O3 and graphene is found to be better than the one with G1 polymer containing β-Bi2O3 and MWCNT. Thermal stability of multifiller nanocomposites is found to be better than the one without nanofillers. AFM topography images show a variation in surface roughness of nanocomposites with different fillers, which contributes to the different micro- and nano-structural architectures due to polymer–nanofiller interaction, thereby, affecting the X-ray attenuation of the nanocomposites. Our study shows that the multifiller nanocomposite containing β-Bi2O3 and graphene nanoplatelets offer greater potential for the development of efficient radiopaque fabric materials. [ABSTRACT FROM AUTHOR]