THERMAL-PROPERTIES OF POLYPROPYLENE RICE HUSK ASH COMPOSITES

Incorporation of rice husk ash (RHA) fillers into polypropylene affect ed some of the thermal properties of polypropylene composites. Additio n of the black rice husk ash (BRHA) filler raised the thermal degradat ion temperature while maintaining the oxidative stability. The thermal degradation temperature of the white rice husk ash (WRHA) composites was found to be independent of filler loading but the oxidative stabil ity deteriorated with increasing filler content. DSC studies indicated that both white and black RHA fillers act as weak nucleation agents a nd increase the degree of crystallinity of polypropylene by a small ma rgin. Addition of the RHA fillers reduced the linear thermal expansion coefficient of the composites. Dynamic mechanical studies showed that the RHA composites with higher filler content have higher storage mod ulus. Tan delta curves of the composites indicated that WRHA filler in creased the damping property while the BRHA filler had an opposite eff ect.