Processing of surface modified nano boron carbide (B4C) containing flexible composites as shielding materials

Aims: The main aim of the work is to synthesize nano boron carbide using cost effective modified sol-gel technique and then functionalize the obtained nanoparticles surface so that they can be homogeneously distributed within flexible polymeric matrices for radiation shielding purposes. Methods: Different starting chemicals were used in sol gel technique to obtain nano boron carbide (B4C) particles with controlled size and morphology. Surface modification with various functional groups was conducted on the synthesized particles and final coated B4C particles were embedded within the polymers using high shear mixing process in the form of thin sheets and plates. Results: It was shown first that nano boron carbide particles can be obtained by a novel modified sol gel technique using nano elemental boron which results in obtaining stoichiometric boron carbide. Surface modified B4C with functional groups resulted in the excellent distribution within polymeric matrices leading to the improvement in both mechanical and shielding properties. Conclusions: Size and morphology controlled B4C can improve the mechanical and shielding properties of polymer based composites. The final obtained composite materials are considered to be suitable candidate for lightweight radiation shielding materials.