Poly(aryl ether ketone) based individual, binary and ternary nanocomposites for nuclear waste storage: mechanical, rheological and thermal analysis

Abstract

In this study poly aryl ether ketone (PAEK) based nanocomposites containing multi walled carbon nanotubes, boron carbide and tungsten carbide nanofillers were irradiated with gamma rays of dosage 5000 kGy. These composites were prepared to estimate their potential in nuclear waste storage applications. The tensile properties, non destructive testing, rheological behavior and thermal properties of the composites were evaluated before and after gamma irradiation. The property variation after irradiation was influenced by the cross linking and chain scission of the polymer developed within the nanocomposites. In the tensile property analysis, the tensile modulus and the percentage elongation at break of all the nanocomposites were modified after gamma irradiation. Non destructive testing (NDT) showed all the samples were free from voids and cracks after gamma rays exposure. There was a slight decrease in the complex viscosity of the samples after irradiation indicating the predominance of the chain scission over cross linking. The decrease in melting temperature and the crystallization temperature of PAEK and the nanocomposites after irradiation suggested changes in the conformation of the polymer chains which was validated by the gel permeation chromatography (GPC) analysis. Even though the properties of the virgin PAEK were significantly reduced after gamma irradiation, the percentage reduction in the properties of polymer nanocomposites was not considerable especially with the ones reinforced with tungsten carbide.