Boron‐containing nonwoven polymeric nanofiber mats as neutron shields in compact nuclear fusion reactors

Abstract

Summary Composite materials that contain thermally and chemically stable boron compounds are attractive candidates for applications that require high neutron absorption due to the large neutron absorption cross‐section of boron. Electrospun polymer nanofibers have a unique volume‐to‐surface area, incorporating carbon and hydrogen atoms in their molecular structure that could moderate and thermalize incident neutrons. Nonwoven nanofibers could in turn reduce neutron scattering and increase neutron absorption by providing large surfaces and better atom economy in the shield materials. The expected high absorption will result from improved neutron interaction with high neutron absorbance hydrogen, carbon, and boron atoms in the nanofibers through increased specific surface area and atom economy. In this work, elemental boron‐doped PVA polymeric nanofibers are produced for the first time to date for the application of neutron shielding. With the increasing demand for nuclear power generation and radiation therapies in medicine, the need for producing lightweight and flexible materials that could replace the traditional heavy metal/metal carbide‐based shields is vital. Similarly, the need for flexible materials that could shield neutrons is also becoming critical for aerospace applications. The effect of boron content on the quality of fibers and neutron shielding capacity is evaluated by using an Am‐Be neutron source. Characterization studies of produced nanofibers were carried out by SEM, TGA, FT‐IR, and XPS analyses. Results have shown that PVA‐based nanofibers doped with wt% 0.1 to 0.5 boron, having fiber diameter distribution between 60 and 330 nm range, could absorb up to 6% of neutron flux.

Boron carbide reinforced electrospun nanocomposite fiber mats for radiation shielding

“…High density increases the interaction probability of matter and photons. [ 47,48,54 ] As seen in Table 2 B 4 C(N)/PVA nanocomposite fiber mat has a relatively higher density. So as a result of increased interaction probability, B 4 C(N)/PVA has a higher linear attenuation coefficient variation against photon energy.…”

“…[ 16,17 ] Other than reducing the filler particles' size, increasing the matrix's overall surface area could be another way to improve the neutron capture capabilities of composite materials. [ 48 ]…”

“…[16,17] Other than reducing the filler particles' size, increasing the matrix's overall surface area could be another way to improve the neutron capture capabilities of composite materials. [48] For the first time in this work, the production of electrospun boron carbide reinforced PVA nanofibers and their utilization as ultra-thin, lightweight, and flexible radiation shielding materials for personal and structural protective materials were investigated. Micron-sized commercial B 4 C powders and sol-gel synthesized B 4 C nanoparticles were used to examine the effect of particle size on the fiber formation.…”

An Optimization Study for the Electrospun Borate Ester Nanofibers as Light‐Weight, Flexible, and Affordable Neutron Shields for Personal Protection

“…Nanofiber mats could protect astronauts and structures in space. [26] Esterified borated PVA nanofibers could be further carburized to create one dimensional boron carbide nanostructures with compromised connected particles. [27][28][29] Diol-diol attraction and cross-linking reduce borate ester solution flowing ability.…”

Decomposition Behavior of Stereocomplex PLA Melt-Blown Fine Fiber Mats in Water and in Compost

“…Melt blowing, comprising drawing of polymer melt by pressurized hot air, is one of the most prominent methods for making fine synthetic fibers in large volumes. MB fibers and related products are used in many applications, including but not limited to automotive, railway, aerospace, agriculture, geotextiles, industrial/military, medical/healthcare and construction [4][5][6]. Among them, demand for personal protective equipment (PPE) made of MB fibers has soared to unprecedented levels due to the COVID-19 pandemic.…”