Comparative study on the flammability of polyethylene modified with commercial fire retardants and a zinc aluminum oleate layered double hydroxide

Abstract

Abstract:Polyethylene (PE) was modified by the addition of a layered double hydroxide of zinc aluminum oleate (ZnAl) and/or commercial fire retardants.NOT THE PUBLISHED VERSION; this is the author's final, peer-reviewed manuscript. The published version may be accessed by following the link in the citation at the bottom of the page.Polymer Degradation and Stability, Vol. 94, No. 5 (May 2009): pg. 782-788. DOI. This article is © Elsevier and permission has been granted for this version to appear in e-Publications@Marquette. Elsevier does not grant permission for this article to be further copied/distributed or hosted elsewhere without the express permission from Elsevier. 2Commercial additives included: melamine polyphosphate (MPP), ammonium polyphosphate (APP), triphenol phosphate (TPP), resorcinol diphosphate (RDP), decabromophenyl oxide (DECA) and antimony oxide (AO). The thermal stability and the combustion behaviors of the new composite polymeric materials are evaluated in TGA experiments and cone calorimetry. At 20% total additive loading, APP and LDH enhance the thermal stability of the PE composites and favor char formation. ZnAl leads to the best reduction in the peak of heat release rate (PHRR), 72%, while the combinations of PE with other additives give reductions in the range 20-40%. The combination of DECA and AO effectively increases the time to ignition and time to PHRR while LDH lowers these two parameters. APP and MPP on the other hand, do not affect the time to ignition, but they effectively increase the time to PHRR relative to the pristine polymer.

Swelling of organoclays in styrene. Effect on flammability in polystyrene nanocomposites

“…The fire behavior of the nanocomposite PS/Nanofil 15 was identical to that of the others nanocomposites but the char was more pronounced and could be seen sticking up in the flame front area as the sample burned. Char formation is good for fire retardancy purposes as the char prevents the entry of flammable gases into the gas phase and insulates the underlying polymer from the flame [29]. Char formation in cone experiments corroborates the observations during UL94 tests, where a char structure formed during burning was observed for the nanocomposites but not for the virgin PS.…”

Strong interfacial attrition developed by oleate/layered double hydroxide nanoplatelets dispersed into poly(butylene succinate)

“…Interestingly a recent work reports the dispersion Zn 2.5 Al/oleale into polyethylene (PE) but with high loading (10-20% w/w) giving rise to an intercalated structure of about 5.1 nm. As fire retardants, the positive role of LDH/oleate filler is underlined for the thermal stability of (PE) as well as the char formation and the reduction of the heat release rate (HRR) peak but it is found to reduce the time to ignition [26].…”

Effect of surfactant alkyl chain length on the dispersion, and thermal and dynamic mechanical properties of LDPE/organo-LDH composites

“…Among all of the methods described, anion exchange is one of the more commonly used and several anionic species, such as phosphates, carboxylates, sulfonates, and sulfates, have been used [18]. Actually, the exchange reaction is controlled by the selectivity of the layered host for the different anions, and in a previous work by Miyata et al [19], it was demonstrated that the selectivity scale of exchangeable anions is as follows: CO LDH!based polymer nanocomposites have been extensively investigated with a large number of polymers, including, epoxy resins [20], polyamide [21], poly(ethylene terepthalate) [22], poly(vinyl alcohol) [23], poly(lactic acid) [24], poly(#-caprolactone) [25], polypropylene [26][27][28][29][30], and polyethylene [15,[31][32][33][34][35][36][37][38][39][40]. Much attention has been focused on preparing LDH polyethylene (PE)-based nanocomposites due to the good balance between processability, mechanical properties, and chemical resistance of this thermoplastic polymer, very suitable for packaging and engineering applications.…”

“…Much attention has been focused on preparing LDH polyethylene (PE)-based nanocomposites due to the good balance between processability, mechanical properties, and chemical resistance of this thermoplastic polymer, very suitable for packaging and engineering applications. In particular, LDH PE!based nanocomposites were prepared by solution intercalation [31][32][33][34] and melting processes [35][36][37][38][39][40]. Costa and coworkers [35,39] first reported the preparation of intercalated/ flocculated LDPE/(dodecyl benzene sulphonate, DBS)-LDH nanocomposites using a melt intercalation process.…”