Polypropylene/Mg3Al–tartrazine LDH nanocomposites with enhanced thermal stability, UV absorption, and rheological properties

Abstract

We report the synthesis of coloured polypropylene (PP)/Mg₃Al–tartrazine layered double hydroxide (LDH) nanocomposites with enhanced thermal stability, UV absorption capacity, and rheological properties using a modified solvent mixing method for the first time. SEM images indicated that the LDH nanoparticles were evenly dispersed within the PP matrix due to the favourable interactions between PP and LDHs. TGA and DSC analysis indicated that the thermal stability of PP/LDH nanocomposites was significantly increased. Decreased G′ and G′′ ascribed to the enhanced mobility (relaxation) of the confined polymer chains at the interface of the PP/LDH layers suggested that the LDH is nano-dispersed in the composites. UV-Vis spectroscopy showed that the addition of Mg₃Al–tartrazine LDH significantly enhanced the UV absorption characteristics of PP. Since tartrazine is a nontoxic additive, these coloured PP/Mg₃Al–tartrazine LDH nanocomposites are expected to have many promising applications such as for food packing and children's toys, etc.