Ammonium polyphosphate pentaerythritol

Delobel, R., Le Bras, M., Ouassou, N., and Alistiqsa, F. 1990. Thermal behaviors of ammonium polyphosphate-pentaerythritol and ammonium pyrophosphate-pentaerythritol intumescent additives in polypropylene formulations. J. Fire Sci. 8 85-92. 

Camino, G., Costa L., and Trossarelli, L. 1984. Study of the mechanism of intumescence in fire retardant polymers Part II—Mechanism of action in polypropylene-ammonium polyphosphate-pentaerythritol mixtures. Polym. Deg. Stab. 7(1) 25-31. 

Le Bras, M. and Bourbigot, S. 1996. Mineral fillers in intumescent fire retardant formulations—Criteria for the choice of a natural clay, filler for the ammonium polyphosphate/pentaerythritol. Fire Mater. 20 39-49. 

Andersson, A., Landmark, S., and Maurer, F.H.J. 2007. Evaluation and characterization of ammonium polyphosphate-pentaerythritol-based systems for intumescent coatings. J. Appl. Polym. Sci. 104 748-753. 

The flammability properties of an intumescent fire retardant PP formulation with added MH has been investigated.65 The results show that the intumescent flame-retardant ammonium polyphosphate-filled PP has superior flammability properties but gives higher CO and smoke evolution. The addition of MH was found to reduce smoke density and CO emissions, in addition to giving superior fire resistance. PP filled with ammonium polyphosphate, pentaerythritol, and melamine has given improved flammability performance, without reducing its mechanical properties. 

At an optimum addition level of only 1.5 w t %, nano-size magnesium-aluminum LDHs have been shown to enhance char formation and fire-resisting properties in flame-retarding coatings, based on an intumescent formulation of ammonium polyphosphate, pentaerythritol, and melamine.89 The coating material comprised a mixture of acrylate resin, melamine formaldehyde resin, and silicone resin with titanium dioxide and solvent. It was reported that the nano-LDH could catalyze the esterification reaction between ammonium polyphosphate and pentaerythritol greatly increasing carbon content and char cross-link density. 

Chiu, S.H. and Wang, W.K., Dynamic flame retardancy of polypropylene filled with ammonium polyphosphate, pentaerythritol and melamine additives, Polymer, 39, 1951-1955, 1998. 

An extensive study was conducted on the effect of chemical and structural aspects of zeolites on the fire performance of the intumescent system, ammonium polyphosphate-pentaerythritol (APP-PER), where a marked improvement of the fire-retardant properties within different polymeric matrices has been observed.56 58 The synergistic mechanism of zeolite 4A with the intumescent materials was investigated using solid-state NMR. Chemical analysis combined with cross-polarization dipolar-decoupled magic-angle spinning NMR revealed that the materials resulting from the thermal treatment of the APP-PER and APP-PER/4A systems were formed by carbonaceous and phosphocarbonaceous species, and that the zeolite enhances the stability of the phosphocarbonaceous species. 

Bourbigot, S., Le Bras, M., Gengembre, L. and Delobel, R. 1994. XPS study of an intumescent coating. Application to the ammonium polyphosphate/pentaerythritol fire-retardant system. Applied Surface Science 81(3) 299-307. 

Camino G, Costa L, Trossarelli L. Study on the mechanism of intumescence in fire retardant polymers. 3. Effect of urea on the ammonium polyphosphate pentaerythritol system. Polym. Degrad. Stab. 1984 7 221-229. 

Intumescence of polyethylene (PE) and PP has been reviewed using as intumescent agents zeolites [36], melamine phosphate and pentaerythritol [37]. Ammonium polyphosphate-pentaerythritol [38], zinc borate and ammonium polyphosphate [39], and APP [40], limiting oxygen index (LOI) [36, 37], cone calorimetry [36] and the UL 94 test [25, 36, 37] have all been used in these studies. 

Intumescent flame retardants (IFR) that contains phosphorus are also used in halogen-free flame-retardant systems. Most reported IFRs are mixtures of the three ingredients, an acid source, a polyol, and a nitrogen-containing compound (Halpem et al. 1984). Since processing of ABS resin requires that the additives withstand temperatures in excess of 200 °C, the commonly used intumescent system, ammonium polyphosphate, pentaerythritol, and melamine, which do not have sufficient thermal stability, cannot be incorporated into ABS resin under normal processing conditions they are usually used in polyolefins. 

FIGURE 11.5 LOI values for polyamide-6,6 films in the absence and presence of various flame retardant/commercial and Cloisite SOB nanoclay combinations (a) ammonium polyphosphate (jb) Proban CC pol3mia- (c) intumescent MPCIOOO (d) ammonium polyphosphate/pentaerythritol 0% flame retardant values for flame retardant and nanoclay-containing films are extrapolated. (From Ref. 26, with permission from the Textile Institute.)... 

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