Synergetic effect of ferrocene and MoS2 in polystyrene composites with enhanced thermal stability, flame retardant and smoke suppression properties

Abstract

As a graphene-like layered nanomaterial, molybdenum disulfide (MoS₂) has gained intensive attention from the materials community. In our research, MoS₂ is firstly modified with ferrocene (Fe–MoS₂) on a large scale and then is used as a nanofiller to prepare PS composites by a masterbatch-based melt blending method. The aim of our present study is to study the synergistic effect of ferrocene and MoS₂ on the thermal stability, fire resistance and smoke suppression properties of the PS composites. It was found that the thermal stability of the PS composite was obviously enhanced upon the introduction of 3.0 wt% Fe–MoS₂. The cone test results indicated that the PS/Fe–MoS₂ composites exhibited superior flame retardance to PS/MoS₂ and PS/ferrocene composites. Furthermore, the addition of Fe–MoS₂ could improve the smoke suppression properties of PS composites, as evidenced by the reduction of the carbon monoxide production rate and smoke production rate (SPR). The total flammable gaseous products from the PS composites were decreased which further led to the inhibition of smoke. Such a significant improvement in thermal stability, fire resistance and smoke suppression properties was mainly attributed to good dispersion of the modified MoS₂ nanosheets, synergistic effects between ferrocene and MoS₂ nanosheets, physical barrier effects of MoS₂ nanosheets and the presence of ferrocene and MoS₂ can promote char formation simultaneously.