Influence and mechanism of ultra-high molecular weight polyethylene on mechanical and electromagnetic shielding properties of alkali-activated composite mortar based on magnesium slag, blast-furnace slag and silica fume

Abstract

Addressing the environmental impact of the magnesium industry's waste, our study presents a sustainable solution by repurposing magnesium slag, blast-furnace slag, and silica fume to create an innovative alkali-activated mortar (MBS-AAM). This research further explores enhancing electromagnetic (EM) shielding capabilities by incorporating ultra-high molecular weight polyethylene (UHMWPE) powder into MBS-AAM. The addition of 0.5 wt% UHMWPE significantly improves the EM shielding effectiveness of the MBS-AAM composite. Specifically, the modified MBS-AAM demonstrates compressive and flexural strengths of 55.0 MPa and 8.5 MPa, respectively, along with a 148.68% increase in EM shielding effectiveness compared to conventional cement mortar. This advancement is attributed to the optimized pore structure, featuring a higher proportion of smaller pores and reduced overall porosity. Our findings highlight a dual benefit: effective waste utilization and enhanced material functionality for EM shielding, offering a promising approach to sustainable construction and waste management within the magnesium industry.