Development of novel composite materials containing rice bran wax and waste polyethylene for neutron shielding applications

Abstract

Neutrons are utilized in diverse fields, such as physics, biology, chemistry, geology, agriculture, medicine, mining, military, and space research. Neutrons interacting with human tissues and cells can cause harm to soft tissues, such as the cornea, and alter cell functionality, leading to the cessation of cell proliferation and resulting in cell/tisssue damage or cancers. Effective protective materials are necessary to enable the safe use of neutrons in these applications. In this study, several samples of novel types of composites were prepared by blending rice bran wax (RBX) with recycled polyethylene (rPE) at five different ratios ranging from 0% to 50%. The RBX in the composites enhances their neutron absorption capacities and while the rPE in the composites reduce their costs. Several essential fast neutron shielding parameters, such as half-value layer, effective removal cross-section, mean free path, and neutron transmission ratio, were calculated with Monte Carlo simulation GEANT4 code. Absorbed dose amount by the samples were determined using a241Am-9Be neutron source. The theoretical and experimental values of the shielding capacities of the novel composites were compared with those of paraffin and traditional concrete. Compared with the reference samples, the new RBX composite samples had higher neutron radiation absorption capacities. The functional groups of the RBX and rPE were identified using Fourier transform infrared (FTIR) spectrophotometry (Bruker Vertex 70v FTIR spectrometer with the attenuated total reflection (ATR) module) in the spectral area of 400–4000 cm−1 with 32 scans. The thermal chareteristics of the samples were determined with the differential scanning calorimeter Mettler-Toledo/DSC1/700. The developed composite materials are useable as protective material against neutron radiation in radiation settings, such as radiotherapy rooms, within and outside nuclear power plants, as well as in settings involving the storage or transportation of radioactive waste.