The dynamic flammability and toxicity of magnesium hydroxide filled intumescent fire retardant polypropylene

Abstract

ABSTRACT:The flammability properties of an intumescent fire retardant polypropylene added with magnesium hydroxide was discussed in this study. To evaluate the flammability of the material, limit oxygen index, smoke emission, tensile strength, and our exploitation dynamic flammability evaluation system, tests were assessed in experiments. The results showed that the intumescent flame retardant ammonium polyphosphate-filled polypropylene has superior flammability properties but higher carbon oxide (CO) concentration and smoke density. By adding some magnesium hydroxide additives in intumescent fire retarded polypropylene, the smoke density and CO concentration decrease; and the compound also has superior fire properties. It is concluded that intumescent system and magnesium hydroxide additives are effective on improving combustion properties for polypropylene. ᭧ 1998 John Wiley & Sons, Inc. J Appl Polym Sci 67: [989][990][991][992][993][994][995] 1998

Synergistic Effect of the Charring Agent on the Thermal and Flame Retardant Properties of Polyethylene

“…IFR works mainly through a condensedphase mechanism. [6][7][8][9][10][11][12][13][14] Ammonium polyphosphate (APP) is most often used as an acid source. It is generally agreed that APP, a precursor of polyphosphoric acid, is capable of affecting the thermal stability of these polymers, presumably because it promotes acid hydrolytic reaction of the substrates.…”

“…[8][9][10][11][12][13][14][15][16][17] It was found that triazines and their derivatives are good charring agents, and that they have excellent charring effect because of their abundant nitrogen and structure of tertiary nitrogen. Their main advantages are a) low toxicity except for a little cyanidric acid formed during the thermal decomposition of the triazine ring, b) no observation of corrosion in the machinery, in which the polymers are processed, c) in case of fire, the absence of dioxin and halogen acids as well as low evolution of smoke, and above all d) the possibility of endowing the polymer with satisfactory flame-proof properties with a smaller amount of additive without excessively impairing the mechanical properties thereof.…”

“…However, little has been reported on the flame retardant mechanism of charring agents on a molecular structure level. [12][13][14][15] In this article, a novel charring agent, an oligomer, was synthesized (see Scheme 1). Its thermal properties and flame retardancy were investigated by thermogravimetric analysis (TGA), the limited oxygen index (LOI), and the UL-94 test.…”

Improving flame-retardant efficiency by incorporation of fullerene in styrene–butadiene–styrene block copolymer/aluminum hydroxide composites

“…It improves flame retardancy of polymers by taking the heat created during burning away to lower surface temperature [8,9]. There have been various investigations on their flame-retardant behavior in recent years [10][11][12]. However, the flame-retardant efficiency of ATH alone is extremely low.…”

Obtaining magnesium hydroxide of micro- or nanostructure on the basis of technical raw materials

“…The use of magnesium hydroxide as a lame retardant is described in many works such as those in references (Camino et al 2001;Howell et al 2000;Chiu and Wang 1998). It is important that the magnesium hydroxide is characterized by a highly developed surface, which affects the uniformity of distribution in the polymer matrix.…”