Preparation of composites of oxidized polyethylene wax and low-density oxidized polyethylene with various inorganic salts, investigation of their high-energy gamma ray absorption and thermal properties
Project no. 27374 · Status: Kapanmış · 2022
Summary
<p>In order to prevent acute, chronic and somatic effects of radiation on humans, protection from radiation is necessary. The main purpose of this study is to produce radiation protection materials that are lightweight, cheap and non-toxic, with high absorption capacity and then to examine their gamma ray protection capabilities and thermal properties.</p><p>In this study, Oxidized Polyethylene Wax (OPE-WAX) and Low Density Oxidized Polyethylene (LOXPE)-Metal (Tungsten, Bismuth, Zinc, Lead, Titanium and Boron Carbide and Boron Nitride) composites were prepared. For this purpose, OPE-WAX and LOXPEcomposites containing metal oxides and metal oxide mixtures in varying proportions (10%, 20%, 30%, 40% and 50%) were obtained. The obtained composites and metal oxides were characterized by FTIR, XRD, Particle Distribution, SEM and TG/DTG methods. The gamma ray linear absorption coefficients (μ) of the composites were calculated using NaI(Tl) scintillation detector. The theoretical absorption coefficients of the composites were calculated hypothetically by considering the fundamental analyzes by the XCOM platform. According to the results of the SEM analysis, it was observed that the metal oxides were homogeneously distributed in the polymer matrix and there was no agglomeration. The permeability parameters semi-permeability (HVL), 1/10 permeability (TVL) and mean free path (MFP) were calculated. In the study, two</p><p>different matrices were used to create the composite. The reason for selecting two different matrices is the different densities of the polymers (dOPE-WAX=0.93 g/cm3, dLOXPE=1.04 g/cm3), the different molecular weights (MAOPE-WAX= 1500 g/mol, MALOXPE=2500 g/mol), the different acid numbers on the polymer chains (Acid NumberOPE-WAX= 19.99 mg KOH/g, Acid NumberLOXPE=24,98 mg KOH/g) and the functionality added to the polymer used. In the study, metal oxides were synthesized in nano-size by acidic or basic hydrolysis methods starting from various metal salts. Boron nitride and boron carbide nanoparticles were purchased. The reason for using various metal oxides in the study is that the material interacting with gamma rays has high density (dWO3=7.16 g/cm3, dBi2O3=8.90 g/cm3, dPbO=9.53 g/cm3, dTiO2=4.23 g/cm3, dZnO=5.50 g/cm3, dB4C=2.50 g/cm3, dBN=2.3 g/cm3) and high atomic number (ZW=74, ZBi=83, ZPb=82, ZTi=22, ZZn=30, ZB=5). The effects of the amounts of metal oxides and metal oxide mixtures used on the thermal properties of the obtained composites were also investigated. It was observed that the thermal stability of the composites prepared with increasing percentages of metal oxide and metal oxide mixtures in the composite composition increased. Respectively, the best adsorptive material was observed to be 50%Bi2O3-LOXPE, which has high absorbency with low adsorptive thickness.</p><p>Keywords: OPE-WAX, LOXPE, WO3, Bi2O3, ZnO, PbO, TiO2, Boron Carbide, Boron Nitride, Nanoparticle, Gamma Ray Linear Absorption Coefficients (μ), Mass Absorption Coefficient, NaI(Tl), Permeability Parameters, Thermal Decomposition, Surface Morphology</p><p>xi</p>