John Milnes

This work presents the effect of a nanoclay and/or phosphorus/halogen based flame retardants on melt and burn dripping behavior of polypropylene. An experimental setup has been constructed to record the real-time melt-dripping behavior in a furnace. All experiments were repeated in a UL-94 set-up to replicate their melt dripping behavior in flaming conditions. A relationship between melt viscosity/rheology and melt dripping intensity of these polymers has been studied. The physical and chemical changes occurring during melt dripping have also been studied by conducting thermal analysis and rheology experiments on molten drops and comparing them with those of respective original polymer samples. The results have shown that during melt dripping a polymer degrades to a considerable extent and its viscosity is affected by the action of the flame retardant at that particular temperature range.