Physico-mechanical comparative study on gamma irradiated high density polyethylene/eggshell and commercial calcium carbonate composites

Chicken eggshell powder (ESP) as natural source of CaCO${}_3$ was incorporated as natural filler into High Density Polyethylene (HDPE).This natural source can be considered as an effective alternative for the commercial calcium carbonate (CC) filler. Characterization of ESP and CC was investigated by FTIR and XRD analysis. HDPE composites filled with 30 phr (ESP) and (CC) were prepared using internal mixer. 2 phr maleic anhydride (MA) was added as compatibilizing agent to HDPE/ESP composite. The prepared composites were vulcanized by using γ-radiation at doses from 50 to 150 kGy. Mechanical and flame retardancy properties of all composites were investigated; composites were thermally analyzed using TGA and DSC. The results showed that, the mechanical properties of HDPE decrease by incorporation of ESP or CC into it, as it was noticed that the mechanical properties of HDPE/ESP composite were better than the mechanical properties of HDPE/CC composite. Moreover, addition of MA led to improvement in mechanical properties of the HDPE/ESP composite. As well, the thermal stability and flame retardancy of the composites increased by adding ESP or CC to HDPE. The results were proved by scanning electron microscopy (SEM).