Effect of modified sepiolite on combustion properties of polypropylene

The sepiolite was modified in the aqueous HCl solution and characterized by scanning electron microscope (SEM) and Fourier transform infrared spectrum (FT-IR). The results show that modified sepiolite has better dispersion and more Si-OH on the surface. With a micro two-screw extruder the modified sepiolite was incorporated in the polypropylene (PP). SEM micrograph reveals that the sepiolite can reach even dispersion in PP. Smoke density and CONE Tests were used to study combustion properties of PP/sepiolite composites. It is observed that adding 1% sepiolite in polypropylene (PP) can decrease smoke density, heat release rate and smoke production rate, and reduce the total heat release and total smoke production.