Flame retardancy study on magnesium hydroxide associated with clays of different morphology in polypropylene matrix

Abstract

Fire retardancy behavior of polypropylene–magnesium hydroxide–clay composites of different morphologies is presented. Layer‐ and needle‐like clay nanoparticles in natural and organically surface modified form have been compared. Fire retardant performance of the composites was evaluated by conical combustor and by horizontal burning test, while the structure was characterized by SEM. Rheological analysis of varied temperature provided further information about the strength of the formed combustion residue. The results confirm that fibrous and layered clay nanofillers act synergistically and can be combined with MH microfillers advantageously for improving the flame retardancy of PP composites. Significant improvements were observed in combustion parameters, as well as in flammability classifications. Combination of montmorillonite and sepiolite type of clays resulted in the increased time to ignition, and markedly decreased heat release rate. These advancements are ascribed to the char stabilizer effect of nanofillers leading to increased strength of the residue. It is also concluded that not only the interaction between micro‐ and nanofillers, but also the nanofillers–nanofillers interaction plays a key role in fire retardant mechanism. Copyright © 2008 John Wiley & Sons, Ltd.

Thermal degradation and flammability behavior of polypropylene/clay/carbon nanotube composite systems

“…also studied the flame retardancy performance of CNT filled PP and managed to reduce the PHRR from 2755 kW/m 2 to 760 kW/m 2 for PP and PP/CNT, respectively. Marosfoil et al . studied the flame retarding effects of magnesium hydroxide, MMT, and sepiolite nanoclay in PP.…”

Synergistic effects of sepiolite on intumescent flame retardant polypropylene

“…It can have a surface area as high as 200-300 m 2 /g, lengths of 0.2-4 µm, a width of 10-30 nm and thickness of 5-10 nm [29]. In a previous study, we found that sepiolite has a good flame retardant synergistic effect with magnesium hydroxide in EVA [30] or PP [31]. However, there are few reports about sepiolite use in IFR polypropylene [32,33].…”

Flame‐retardant synergism of sepiolite and magnesium hydroxide in a linear low‐density polyethylene composite

“…[16][17][18][19] Significant improvements in flammability and combustion parameters were observed when MH and different types of clays were used. 20 Sepiolite has a chainlike structure with the chemical formula Si 12 Mg 8 O 30 (OH) 4 (OH 2 ) 4 8H 2 O, and it has been used for the preparation of polymer composites. 21,22 The structure of sepiolite is quite similar to the structure of MH, and it also contains water of hydration and can be used with MH.…”