Development of Stearic Acid Coated Fly Ash Reinforced Recycled Polypropylene Matrix Composites and their Thermal Analysis

The industrial wastes fly ash (FA) and polypropylene (PP) were used to develop novel green composites using a renewable, cheap coupling agent i.e. stearic acid. The fly ash (FA) particles were coated with stearic acid (SA) in different weight % like 0, 1, 2, 3 and 5. The SA coated fly ash particles were incorporated as filler in recycled polypropylene (RPP) matrix which was obtained from post-consumer plastic products by melt mixing in 1:1 weight ratio. The composites were tested for dynamic mechanical properties (DMA) and thermogravimetric analysis (TGA). The DMA results showed enhancement in mechanical properties indicated by the shift in the glass transition temperature to a higher value. In 1wt% SA coated FA/RPP (RFASA1) composites highest improvement in the dynamic mechanical properties were observed. Increase in thermal stability in the stearic acid treated composites was also witnessed. The RFASA1 composites showed a highest rise in the onset of thermal degradation temperature. The SA treated composites also showed a considerable increase in the activat ion energy values from that of 0 wt % SA treated FA/RPP (RFASA0) indicating their enhancement in thermal properties in presence of the coupling agent. Thus, an unconventional coupling agent stearic acid could be used in place of commonly used silane coupl ing agents to develop composite materials FA and RPP with tailor made properties. Index Terms – Composites, Coupling agent, Dynamic Mechanical Analysis, Fly ash, Recycled Polypropylene, Stearic acid, Thermogravimetric analysis.