Thermomechanical behaviour of zirconia-multiwalled carbon nanotube-reinforced polypropylene hybrid composites

The present investigation reveals the effect of addition of zirconia-coated multiwalled carbon nanotubes (MWCNTs) on mechanical and thermal properties of polypropylene (PP) matrix composites. Initially, zirconia coating on MWCNTs (ZrO2-CNT) has been performed with the help of isothermal hydroxylation technique and confirmed through typical microstructural and morphological characterizations. Thereafter, the effect of zirconia of mechanical and thermal properties of PP matrix composites has been studied through comparing the thermal decomposition behaviour, tensile and thermomechanical properties of pure PP, MWCNT-reinforced PP composite and ZrO2-CNT-reinforced PP hybrid composite. In short, the addition of 5 wt% CNTs improved tensile modulus by 22%, tensile strength by 16% and storage modulus by 45%, while the addition of same amount of ZrO2-CNT improved the above sequenced properties by 44, 47 and 73%, respectively. Moreover, ZrO2-CNT/PP hybrid composite has been found to have better thermally stability than pure PP as well as CNT/PP composite.