Manufacturing process and properties of lead-free natural rubber sponge for use in X-ray and gamma ray shielding applications

Abstract

In this work, light-weighted, flexible, and lead-free X-ray/gamma-ray shielding natural rubber (NR) sponges were developed with the help of a blowing agent, namely Oxybis (benzene sulfonyl) hydrazide (OBSH) (its contents varied from 0, 8 to 16 parts per hundred parts of rubber; phr), and an X-ray/gamma protective filler, namely bismuth oxide (Bi2O3) (its content varied from 0, 100, 300, to 500 phr) in natural rubber (NR) composites. The results suggested that the densities and overall mechanical properties decreased with increasing contents of OBSH, while the increases in B2O3 resulted in the increases in tensile strength and hardness (Shore A), however, initially increases tensile strength and elongation at break but later decreases at 300 and 500 phr. In terms of radiation shielding properties, it was found that the ability to attenuate X-rays and gamma rays improved with increasing Bi2O3 contents. Hence, the overall properties investigated in this work suggested that the developed NR sponges could be used to attenuate X-rays and gamma rays efficiently with additional properties of being light-weighted and highly flexible, which are crucial for safety of radiation-related personnel and users.