Multigram-scale fabrication of organic modified MoS2 nanosheets dispersed in polystyrene with improved thermal stability, fire resistance, and smoke suppression properties

Abstract

A multigram-scale fabrication method was developed to modify molybdenum disulfide (MoS₂) nanosheets with cetyl trimethyl ammonium bromide (CTAB), and the CTAB-modified MoS₂ nanosheets (CTAB-MoS₂) were applied to improve the properties of polymers. CTAB-MoS₂ dispersed well in organic solvents and was incorporated into polystyrene (PS) by a masterbatch-based melt-blending method. The morphology, thermal behavior, fire resistance, and smoke suppression properties of the nanocomposites were studied. The CTAB-MoS₂ nanosheets dispersed well in PS and exhibited a partial exfoliation structure. The incorporation of 3 wt% CTAB-MoS₂ nanosheets led to an increase in thermal degradation temperature (43–60 °C) and char formation as well as a reduction of the peak heat release rate (PHRR) (20%). Moreover, the addition of CTAB-MoS₂ nanosheets significantly decreased the smoke production rate (SPR), the peak specific extinction area (peak-SEA) values (52% reduction), and the gaseous products. The improvements in the thermal stability, fire resistance, and smoke suppression properties of PS nanocomposites were ascribed to good dispersion of modified MoS₂ nanosheets, physical barrier effects, and catalytic char function of MoS₂ nanosheets.