Characterization of Thevetia Peruviana (Yellow Oleander) Shell Ash Powder as a Possible Filler in Polymer Composites

In this study, the characterization of Thevetia Peruviana shell powder and Thevetia ash powder incinerated at various temperatures (400, 500, 600, 700, 800 and 900ᵒC) is presented. The Thevetia shells were sourced, sun dried for three days and thereafter grounded into powder. The process of making the ash involves heating the powder to the desired temperature followed by conditioning it at the same temperature for 3 hours and then cooling to a room temperature in the furnace. Elemental compositions of both Thevetia shell powder (TSP) and Thevetia ash powers (TAP) were determined using SEM-EDS analysis. The crystallinity, as well as the phases present, was evaluated with the aid of X-ray diffraction (XRD) and the results revealed that TSP is completely amorphous while TAP showed some level of crystallinity depending on the ashing temperature. Through Fourier Transform Infrared (FTIR), functional groups peculiar to TSP and TAP were elucidated which characterize both the shell powder and the ash samples. Thermal stability of the TSP and TAP was studied using differential scanning calorimetry in the temperature range (25-350ᵒC) and the absence of volatile matters and moisture were observed in the ash samples. Scanning electron microscopy study of the samples showed that TSP image is smooth without porous structure while TAP images are fine, rough and porous, thus making the ash suitable filler materials in polymer matrix composites. Finally, Thevetia powder ashed at 600ᵒC has proven to be the best candidate filler material in the polymer matrix due to its high silica to alumina ratio as well as its characteristic morphology.