Flame retardancy and mechanical properties of poegmah compatibilized rice husk filled polypropylene composites

Abstract

Flammability of Polypropylene, PP has restricted its usage as a versatile synthetic polymer. The addition of flame retardants will lower the flammability of PP. However, it will lower the mechanical properties. In this study, the flame retardancy of PP composite has been enhanced by the addition of intumescent flame retardant. Four formulations have been prepared, without flame retardant and with increasing concentration of flame retardant which are 20phr, 25phr and 30phr. The flammability of the composites has been measured using the Limiting Oxygen Index based on ASTM D2863. Two types of mechanical testing have been done to determine the mechanical properties, which are flexural test (ASTM D790) and impact test (ASTM D256). The thermal analysis has been done by thermogravimetry analysis (TGA) to determine the thermal stability of the composites prepared. Morphological study by scanning electron microscopy (SEM) has been done to study the filler distribution. Results obtained from the flammability test indicate that the addition of flame retardant has strongly improved the flame retardancy. The flexural strength and impact strength decreases as the concentration of flame retardant increases while the flexural modulus increases. The thermal analysis has proven that the composites with flame retardant have better thermal stability as compared to the composite without flame retardant. The morphological study has shown that the addition of flame retardant did not affect the filler distribution. The filler remain well distributed as the flame retardant introduced to the composites.