An investigation on non-flammability properties of polypropylene knitted fabrics

The research performed in recent years regarding synthetic filament yarns is improving the structures and properties of such yarns, and diversifying their usage areas. Most of the current studies being carried out in this field are in the form of bringing functionality to filament yarns. And one of these functional properties is the production of flame-retardant yarns from different types of polymers. In this study, polypropylene (PP) raw material was mixed with organophos- phonate based flame retardancy additive at rates in between 1% and 8% in the feed hopper of a laboratory-type melt spinning machine during PP filament yarn production and then knitted fabric structures were obtained from these yarns. Then the flame retardancy properties of these PP knitted fabrics were tried to be determined by vertical flammability tests and Limit Oxygen Index (LOI) tests. Test results indicated that after flame time and char length values had significantly decreased and values of LOI had increased in knitted fabrics by the increase in additive rate. In conclusion, it was observed that the increase in the rate of flame retardancy additive had significantly improved the non-flammability properties of the PP samples.