Shielding Properties Enhancement of Bentonite Clay Nano Particles Coated by Polyvinyl Alcohol Polymer

Abstract

Calcination process is a method used for gamma rays mass attenuation coefficient enhancement of natural bentonite clay nano-particles. This process eliminates water and organic matter from bentonite clay structure which have low mass attenuation coefficient values. There are two opposite effects on mass attenuation coefficient values; oxides content increases after calcination process which enhances mass attenuation coefficient values and particle size of calcinated bentonite increases which decreases mass attenuation coefficient values. In order to enhance mass attenuation coefficient value for natural bentonite, a physical ball milling must introduced after calcination process that decreases particle size. Calcination process is done at 700 ̊C for two hours because dehydration is completed above 500 ˚C while dehydroxylation observed at 700 ˚C. Mass attenuation coefficients are measured for calcinated and ball milled bentonite clay at different energies (662, 1173 and 1332 keV) and different pressing pressures (50, 100 and 150 bar). Narrow beam transmission technique and two different sources (Cs-137 and Co-60) are used for mass attenuation coefficient measurements, also particle size are measured by two different methods dynamic light scattering and Williamson-Hall size analyses using XRD patterns. All samples are coated by polyvinyl alcohol polymer.

The Effect of Particle Size of Polyvinyl Alcohol/Bentonite Clay Mixture on the Radiation Shielding: A Monte Carlo Study

“…Polyvinyl alcohol is an artificial polymer that has been used worldwide since the first half of the twentieth century, and it is produced from polyvinyl acetate through hydrolysis. It has been applied in various industries, including the industrial, medical, and food sectors, for the production of many end products such as resins, surgical threads, and food packaging materials that often come into contact with food [12,13]. The non-toxic and non-corrosive nature of PVA polymer, its water solubility, high optical transparency, and thermal stability make it a suitable matrix for optoelectronic and various other applications [14][15][16].…”

Mass attenuation Coefficient and Total cross-section Area of Platinum Group Composition

“…These coefficients are profoundly influenced by the physical state and composition of the material under consideration. Various factors such as the energy of incident gamma radiation, atomic number, density of elements in the shielding material, and the thickness of the shielding play integral roles in determining a material's efficacy in blocking gamma rays (Sallam et al, 2021). The mass attenuation coefficient specifically quantifies the probability of interaction between incident photons and the matter, expressed as the unit mass per unit area.…”