Flexible Composites of Barium Sulfate Modified by Tannic Acid Using Glycerol/Starch for X-Ray Shielding Applications

Abstract

This study investigates the X-ray shielding properties and mechanical properties of barium sulfate (BaSO₄) composites based on a biodegradable matrix composed of glycerol and starch. In addition, tannic acid (TA) is used for surface modification of the BaSO₄. Increasing the amount of BaSO₄ is necessary to improve the composite's X-ray shielding properties; however, as the amount of BaSO₄ increases, the composite becomes harder. The purpose of this research is to prepare a flexible X-ray-shielding composite even when a large amount of filler is added. TA easily coats the BaSO₄ surface, and its presence is confirmed by Fourier transform infrared spectroscopy and thermogravimetric analysis. Elongation of the composites composed of glycerol, starch, and BaSO₄ is increased by 50% because of the formation of hydrogen bonds between the hydroxyl groups of glycerol and starch and those of TA. Consequently, the fracture behavior changed from brittle fracture to ductile fracture. However, the X-ray shielding properties are not changed by the surface modification with TA. The use of glycerol, starch, and BaSO₄ is a new approach to the development of biodegradable radiation shielding materials. In addition, as a surface-modification agent, TA is environmentally friendly. All of the composites are prepared from natural materials.