MoS2@Fe3O4 prepared by γ-ray in situ reduction for enhancing the fire safety and mechanical properties of EVA/MCA composites

Abstract

The high flammability of ethylene vinyl acetate copolymers (EVA) limits its important applications in fire safety, and the addition of highly effective flame retardants can improve this deficiency. Melamine cyanurate (MCA) has limited carbon-forming ability and therefore is often combined with other flame retardants to achieve synergistic flame retardant effects and thus improve the flame retardancy of EVA. Therefore, in this study, MoS2@Fe3O4 hybrid materials were synthesized by in-situ growth of molybdenum disulfide (MoS2) and ferric oxide (Fe3O4) and their structures were characterized using various techniques. The hybrids were blended with melamine cyanurate (MCA) into ethylene vinyl acetate copolymer (EVA) by melt blending method to reduce the fire hazard. The EVA composites with 1.0 wt% MoS2@Fe3O4 blends significantly improved the coke residue and limiting oxygen index values to 22.5 % and 23.2 %, while their peak heat release rate, total heat release, and total smoke release were reduced by 62.5 %, 11.7 %, and 35.3 %, respectively, as compared to pure EVA. The results suggest that the use of MoS2@Fe3O4 hybrids in combination with MCA is a promising strategy for the development of advanced flame-retardant materials.