Layered Double Hydroxide (MgFeAl-LDH)-Based Polypropylene (PP) Nanocomposite: Mechanical Properties and Thermal Degradation.

This work analyzes the thermal degradation and mechanical properties of iron (Fe)-containing MgAl layered double hydroxide (LDH)-based polypropylene (PP) nanocomposite. Ternary metal (MgFeAl) LDHs were prepared using the urea hydrolysis method, and Fe was used in two different concentrations (5 and 10 mol%). Nanocomposites containing MgFeAl-LDH and PP were prepared using the melt mixing method by a small-scale compounder. Three different loadings of LDHs were used in PP (2.5, 5, and 7.5 wt%). Rheological properties were determined by rheometer, and flammability was studied using the limiting oxygen index (LOI) and UL94 (V and HB). Color parameters (L*, a*, b*) and opacity of PP nanocomposites were measured with a spectrophotometer. Mechanical properties were analyzed with a universal testing machine (UTM) and Charpy impact test. The thermal behavior of MgFeAl-LDH/PP nanocomposites was studied using differential scanning calorimeter (DSC) and thermogravimetric analysis (TGA). The morphology of LDH/PP nanocomposites was analyzed with a scanning electron microscope (SEM). A decrease in melt viscosity and increase in burning rate were observed in the case of iron (Fe)-based PP nanocomposites. A decrease in mechanical properties interpreted as increased catalytic degradation was also observed in iron (Fe)-containing PP nanocomposites. Such types of LDH/PP nanocomposites can be useful where faster degradation or faster recycling of polymer nanocomposites is required because of environmental issues.