Improved pyrolysis behavior of ammonium polyphosphate-melamine-expandable (APP-MEL-EG) intumescent fire retardant coating system using ceria and dolomite as additives for I-beam steel application

Abstract

This study describes the effects of ceria (CeO 2) and dolomite [CaMg(CO 3) 2 ] additives on the pyrolysis behavior and fire resistive property of conventional intumescent flame retardant (IFR) coating system for I-beam steel substrate called ammonium polyphosphate-melamine-expandable graphite (APP-MEL-EG) system. The fire resistance of various formulations was evaluated using the standard vertical Bunsen burner fire test. Thermogravimetric analysis (TGA) was used to understand the degradation of coating formulations. Observations by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) demonstrated that significant amounts of additives favored the formation of homogeneous compacted char structures, which were predominantly composed of carbon (C), phosphorus (P) and oxygen (O). These three main components of the char were also found to be in various binding combinations with other lighter elements like nitrogen (N) and hydrogen (H) as illustrated by the attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy results. X-ray photoelectron spectroscopy (XPS) further suggest that polyethylene([(CH 2-C 2 H 2-CH 2) nÀ ]) free radicals were abundant on the char surface for the two best formulations and the binding energy of this radical promoted the formation of aromatic carbon chains that enhanced the char's thermal stability. This means that the selection of appropriate additives and combinations of flame-retardant ingredients could significantly change the morphology of the char layer and improve its thermal stability during fire exposure.

Synthesis and characterization of coal fly ash and palm oil fuel ash modified artisanal and small-scale gold mine (ASGM) tailings based geopolymer using sugar mill lime sludge as Ca-based activator

“…As for the broad peak between 3000 and 3700 cm −1 , this is assigned to O–H vibrations of crystalline and/or free water molecules ( Tabelin et al., 2017c ; Zoleta et al., 2020 ). The presence of carbonate minerals is also implied by the broad IR absorption peak between 1600 and 1300 cm −1 in PA and MT.…”

Facile Synthesis of Band Gap-Tunable Kappa-Carrageenan-Mediated C,S-Doped TiO2 Nanoparticles for Enhanced Dye Degradation

“…The narrow scan spectra of oxygen (O 1s), carbon (C 1s), titanium (Ti 2p), and sulfur (S 2p) were obtained and corrected using the binding energy of adventitious carbon (285.0 EV). All XPS spectra were deconvoluted with XPSPEAK version 4.1 using a true Shirley background and a 20–80% Lorentzian–Gaussian peak model. , The specific surface area and pore size were analyzed using a BELSORP MAX X analysis instrument.…”

“…All XPS spectra were deconvoluted with XPSPEAK version 4.1 using a true Shirley background and a 20–80% Lorentzian–Gaussian peak model. 68 , 69 The specific surface area and pore size were analyzed using a BELSORP MAX X analysis instrument.…”

Improved Pyrolysis Performance of a Cyclic Phosphate‐Melamine Intumescent Fire‐Retardant Coating System Using Ceria as an Additive

“…For example, Zoleta et al. (2020) added ceria and dolomite to the fire‐retardant coatings of the ammonium polyphosphate‐MEL‐expandable graphite system and found that ceria not only catalyzes the release of water but also promotes the formation of P−O free radicals, thereby enhancing carbon strength [12] . Liu et al.…”

“…For example, Zoleta et al (2020) added ceria and dolomite to the fire-retardant coatings of the ammonium polyphosphate-MELexpandable graphite system and found that ceria not only catalyzes the release of water but also promotes the formation of PÀ O free radicals, thereby enhancing carbon strength. [12] Liu et al (2020) recycled powders with large amounts of flameretardant compositions from the precipitate of industrial effluents and applied them in an intumescent fire-retardant coating; such a high-performance intumescent flame-retardant coating is promising in the industry. [13] In the present study, the synergistic fire resistance of ceria and PEA on epoxy intumescent fire-retardant coatings was studied.…”