An efficient approach to improving fire retardancy and smoke suppression for intumescent flame-retardant polypropylene composites via incorporating organo-modified sepiolite

In this work, an efficient approach to improving the fire retardancy and smoke suppression for intumescent flame-retardant polypropylene (PP) composites is developed via incorporating functionalized sepiolite (organo-modified sepiolite [ONSep]). The PP composites with different amounts of intumescent flame retardants and ONSep were prepared by melt compounding. The morphology, thermal behavior, fire retardancy, smoke suppression, and mechanical property of flame-retardant PP composites were studied. The results indicate an appropriate amount of ONSep in the flame-retardant PP composites can increase thermal degradation temperature and char formation as well as a reduction of the peak heat release rate and total heat release; moreover, the addition of ONSep significantly decreases the CO production, total smoke production, smoke production rate, and smoke temperature. Simultaneously, the impact strength of intumescent flame-retardant PP composite is also maintained by introducing an appropriate amount of ONSep as compared with that without ONSep.