Synergistic Effects of Mixed Metal Stearate, Calcium Carbonate Particles and Recycled Low Density Polyethylene on The Mechanical, Thermal and Structural Performance of Polyvinylchloride Blend.

Abstract Thermo-mechanical recycling process is the cheapest way to recover plastic wastes such as LDPE with lower ecological impact, thus, the target in this work is to achieve high performance microcomposites prepared from polyvinyl chloride (PVC), recycled low density polyethylene (r-LDPE), calcium carbonate (CaCO3) and Calcium/Zinc stearate (CaSt2/ZnSt2). The effects of two ratios of thermal stabilizers with different concentrations, on the mechanical properties and thermal stability of PVC and PVC/r-LDPE (1:1) blend were studied. The samples were characterized using infrared spectroscopy (FTIR), mechanical tests, thermal analysis and scanning electron microscopy (SEM). The addition of 5 phr of CaSt2:ZnSt2 = 9:1 into PVC (MC4) seems to produce an optimum tensile strength and elongation at break values. In addition, it is highlighted that MC4 showed a high thermal stability. Moreover, the incorporation of r-LDPE into PVC makes the PVC matrix stronger and more stable than pure PVC which yields to high mechanical and thermal performances. Furthermore, an outstanding synergistic effect can be showed when heat stabilizer rich in calcium combined with CaCO3 and r-LDPE. This PVC/r-LDPE blend as waste composite can be used in several industry fields. Finally, we used DFT calculation to elucidate the dehydrochlorination mechanism of PVC in presence of Ca and Zn stearate.