Thermal behavior, flame retardant and rheological properties of low density polyethylene filled with slag

In recent years, the massive discharge and irrational accumulation of slag have led to the waste of land resources and serious environmental pollution problems. In this work, to explore the potential applications of slag, it was modified with silane coupling agent 3-aminopropyltriethoxysilane (KH-550) to improve its compatibility with polymer matrix. A series of low density polyethylene (LDPE)/modified slag (MS) composites were prepared using melt blending method. The results showed that the introduction of MS significantly improved the thermal and mechanical properties of LDPE in comparison to those of its pure form. The tensile strength, tensile modulus, and T_d5% of the LDPE/MS composites with 40 wt% MS content were enhanced by 58%, 113%, and 19.9 ℃, respectively. Furthermore, dynamic rheological analysis revealed that a higher MS filler content resulted in a higher restriction on the movement of the LDPE molecular chains. The application of slag in LDPE provides a feasible method of recycling slag and promoting sustainable development.