Intumescent Fire Retardant Coating Research Articles

Effect of basalt fibres reinforcement and aluminum trihydrate on the thermal properties of intumescent fire retardant coatings

This research is carried out in order to study the synergistic effect of aluminium trihydrate and basalt fibres on the properties of fire resistant intumescent coatings. Intumescent fire retardant coatings were developed using different flame retardants such as ammonium polyphosphate, expandable graphite, melamine and boric acid. These flame retardants were bound together with the help of epoxy binder along with curing agent. Furthermore, individual and combinations of aluminium trihydrate and basalt fibres was incorporated in the formulations to analyse mechanical and chemical properties of the coatings. Char expansion was observed using furnace test, thermogravimetric analysis was used to determine residual weight, X-Ray Diffraction was performed to investigate compounds present in the char, shear test was conducted to determine char strength and scanning electron microscopy analysis was performed to observe morphology of the burnt char. From the microscopic investigation it was concluded that the dense structure of the char increased the char integrity by adding basalt and aluminium trihydrate as fillers. X-Ray Diffraction results shows the presence boron phosphate, and boric acid which enhanced the thermal performance of the coating up to 800°C. From the Thermogravimetric analysis it was concluded that the residual weight of the char was increased up to 34.9 % for IC-B2A4 which enhanced thermal performance of intumescent coating.

Synergistic Flame Retardant Effects of Different Zeolites on Intumescent Fire Retardant Coating for Wood

To investigate the fire-retardant properties of intumescent fire-retardant coatings of wood modified by different zeolites, tests were conducted by a cone calorimeter with poplar samples whose surfaces were covered by an intumescent fire-retardant coating modified by 3A, 4A, 5A, 13X zeolites, respectively. Results indicated that the ignition time (TTI) of the intumescent fire-retardant coating modified by 3A zeolite was prolonged 120 s, while the total smoke production (TSP) increased 60.1% as compared with the untreated group. The intumescent fire-retardant coating modified by the 13X zeolite had a smaller smoke production rate (SPR) and was the last to reach the peak-SPR. Its TSP remained in a very low state until 410 s and decreased 25%. Thus, 3A zeolite and 13X zeolite were of complementarily synergistic effects on improving the fire-retardant properties of an intumescent fire-retardant coating for wood. This paper suggested the alternative types of zeolites for flame-retardant coatings.

Synergistic Effects of Titanium Dioxide and Zinc Borate on Thermal Degradation and Water Resistance of Epoxy Based Intumescent Fire Retardant Coatings

Abstract. This studies discuss the synergistic effects of titanium dioxide (TiO2) and zinc borate on thermal stability and water resistance of intumescent fire retardant coatings. TiO2 in association with a traditional intumescent flame retardant system which contains ammonium polyphosphate/expandable graphite/melamine/ zinc borate (APP–EG–MEL-ZB) was introduced to epoxy based coatings to improve the fire resistance. The influences of TiO2 on the properties of the coatings were investigated in detail by using Bunsen burner fire test, thermogravimetric analysis (TGA), scanning electron microscope (SEM) and water immersion test. Bunsen burner test revealed that incorporation of titanium dioxide in intumescent formulation reduced the steel substrate temperature from 240 °C to 116 °C. The TGA results proved that addition of TiO2 could enhance the anti-oxidation of the char layers and increase the residue weights of the coatings. The FESEM images demonstrated that addition of TiO2 could improve the foam structure of the char residue. Sea water resistance test demonstrated that the optimum mass % age of TiO2 (6%) exhibited great synergism with natural anti-corrosion agent, zinc borate, and improved corrosion resistance performance of intumescent coating formulations.

The Role of Bentonite Clay on Improvement in Char Adhesion of Intumescent Fire-Retardant Coating with Steel Substrate

The adhesion of char with the substrate is important in improving the fire protection of substrate. This study presents the effects of bentonite clay on intumescent fire-retardant coating for improving the adhesion of char with steel substrate, thermal performance and residual weight of intumescent fire-retardant coatings. A range of expandable graphite-based intumescent coating formulations were developed using a shear mixer with various additives. In a selected formulation, bentonite clay additive was incorporated to investigate the improvement in adhesion of coating and char with steel substrate. The substrate was sandblasted and coated with a primer coating of zinc phosphate followed by intumescent coating. Char expansion and fire performance were measured by furnace fire test and Bunsen burner test. Residual weight was determined by thermogravimetric analysis, and char detachment was measured by scanning electron microscopy. The bonding shear strength was measured according to ASTM 3163. Results showed improvement in residual weight to 33.45 wt%. The substrate temperature was reduced to 170 \(^{\circ }\hbox {C}\), and char separation was reduced to 130 \(\upmu \hbox {m}\). Shear strength was improved to 9.90 MPa for an intumescent coating formulation containing 6 wt% of bentonite clay and 1.75 MPa for formulation without bentonite clay.

Thermal and pyrolysis analysis of minerals reinforced intumescent fire retardant coating

Abstract This study presents the results of intumescent fire retardant coatings (IFRCs) developed to investigate the synergistic effects of mineral fillers (clay and wollastonite) based IFRC towards heat shielding, char expansion, morphology, composition, gaseous products and residual weight. The fire test has been performed to study the heat shielding effect of IFRCs on the substrate using UL-1709 standards. The results showed the synergistic effect of clay and wollastonite using 5 wt.% enhanced the fire protection, performance with recorded substrate temperature 113 °C after 1-h fire test. Field Emission Scanning Electron Microscopy (FESEM) and High-Resolution Transmission Electron Microscopy (HRTEM) showed the micrograph of compact char structure that increased char integrity due to the presence of inorganic fillers. X-ray Diffraction (XRD) and Fourier Transform Infrared Spectroscopy (FTIR) results showed the presence of boron phosphate, silicon phosphate oxide, aluminum borate in char that improved the thermal performance of IFRC up to 800 °C. X-Ray Photoelectron Spectroscopy (XPS) confirmed that 5 wt% (IFRC-5) of clay and wollastonite increased the carbon content up to 50.67%, lowering oxygen content to 27.73% in the char that enriched the fire resistance performance of the coating. Pyrolysis-Gas Chromatography-Mass Spectrometry (Pyrolysis GC–MS) confirmed that formulations IFRC-5 released less gaseous product concentration compared to IFRC-C and maximum reduction in gases was recorded from 3.4e +07 to 1.08e +07 . Thermogravimetric analysis (TGA) demonstrated in residual weight was increased to 46.45% for IFRC-5 which resulted in the high thermal stability of the coating.

Effects from nano-titanium oxide on the thermal resistance of an intumescent fire retardant coating for structural applications

Abstract Due to its effective performance, intumescent fire retardant coating (IFRC) is widely used by oil and gas industries as well as in processing and petrochemicals plants to protect metallic substrates from fire. The present work developed an epoxy based IFRC comprising phosphate, nitrogen, barium and boron containing flame-retardants. The product was reinforced with nano-titanium oxide and then examined for performance with a lab scale hydrocarbon fire test. Thermal analysis of the coating was evaluated using TGA and DTGA under nitrogen and oxygen environments. Further characterization studies included FESEM, EDS, FTIR, XRD and XRF to determine effects from nano titanium oxide on char’s performance. Results indicated that a coating reinforced with 4.5 wt% of nano-TiO 2 added residual weight to the coating and provided longer thermal protection time compared to conventional fire retardant coatings.

Effects of nano-sized boron nitride (BN) reinforcement in expandable graphite based in-tumescent fire retardant coating

The purpose of in-tumescent fire retardant coating (IFRC) is to protect substrate from fire attack by limiting heat transfer. A range of coating formulations have been prepared using Bisphenol A epoxy resin BE-188 and polyamide solidifier H-2310 as two-part binder, ammonium polyphosphate (APP) as acid source, melamine (MEL) as the blowing agent, expandable graphite (EG) as carbon source and nano-boron nitride (BN) as inorganic nano filler. The filler was used to improve the performances of the APP-EG-MEL coating. The effects of nano-BN on the char morphology and thermal degradation were investigated by fire test, thermo gravimetric analysis (TGA), Fourier transform infrared spectroscopy (FTIR), X- ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FESEM). The results showed that by substituting or reinforcing of 4% weight percentage of nano-BN, residual weight of the char increases by 23.82% compared to APP-EG-MEL coating without filler. Higher carbon content was obtained in the char and a more compact char was produced. The results indicated that nano-BN could be used as a filler to improve thermal stability of the APP-EG-MEL coating.

Preparation and performances of novel waterborne intumescent fire retardant coatings

Abstract The core–shell organic-modified montmorillonite (OMMT)/epoxy resin/styrene-acrylic emulsion was prepared using semi-continuous seeded emulsion polymerization and used as the binder of the waterborne intumescent fire retardant coating to improve the fire resistance performance and other basic performance such as water resistance performance, anti-yellowing and adhesion to substrates. Observation with transmission electron microscopy showed that core–shell emulsion had been synthesized successfully. The small angle X-ray diffraction results showed that OMMT was exfoliated and dispersed well in the emulsion within the appropriate content. Fire resistance test, thermal analysis, scanning electron microscopy (SEM), water resistance and yellowing resistance test respectively demonstrated that OMMT greatly improve fire resistance, thermal stability, water resistance and yellowing resistance performance with the addition of in the range of 1.5–2.5 wt.%. Moreover, the core–shell styrene-acrylic emulsion with 5 wt.% epoxy resin (E-44) improve the adhesion of the film to plywood (from 2 grade to 0 grade).

Effect of Dolomite Clay on Thermal Performance and Char Morphology of Expandable Graphite Based Intumescent Fire Retardant Coatings

Dolomite Clay was introduced in a traditional intumescent flame retardant system which contains ammonium polyphosphate/expandable graphite/melamine (APP–EG–MEL) to evaluate its effects on char morphology and fire performance. The effect of dolomite clay on the fire-resistance and thermal properties of expandable graphite based Intumescent fire retardant coatings has been investigated by using Bunsen burner fire test and thermal gravimetric (TG) techniques. The current study describes the effects of Dolomite Clay on the heat shielding performance of intumescent passive fireproofing coatings during fire testing. The fire performance of dolomite clay reinforced intumescent coating formulations were evaluated by Bunsen burner fire test according to ASTM E-119. Results showed that the dolomite reinforcement in IFRC formulation significantly reduced the steel substrate temperature up to 180°C after 1 hour of fire exposure. The coating degradation was studied using thermogravimetric analysis (TGA). The physical morphology and alignment of intumescent char residue were studied by field emission scanning electron microscopy (FESEM). TGA analysis revealed that IFD (8) containing 8wt. % of dolomite clay enhanced residual weight by 37.30%. It is suggested that Dolomite clay can enhance the fire performance and can significantly affect the formation of dense and continuous char if incorporated as a filler in conventional intumescent fire resistive systems.

Smoke suppression and synergistic flame retardancy properties of zinc borate and diantimony trioxide in epoxy-based intumescent fire-retardant coating

In this article, smoke suppression and synergistic flame retardancy properties of zinc borate (ZB) and diantimony trioxide (Sb2O3) in epoxy-based intumescent fire-retardant (IFR) coating were investigated based on cone calorimeter test, smoke density test, scanning electron microscopy, thermogravimetric and Fourier transform infrared spectroscopic analyses. The measurement results of the dynamic combustion and smoke production behaviors and static smoke production behaviors of these IFR coatings showed that the values of heat release rate, smoke production rate, smoke factor and fire growth index all decreased significantly with the addition of ZB and Sb2O3. At the same time, the specific optical densities were remarkably reduced due to the existence of ZB and Sb2O3. These attractive data clearly demonstrated that the ZB and Sb2O3 had a good effect on smoke suppression and synergistic flame retardancy of the IFR coating. Besides, the scanning electron microscopy and the infrared spectroscopic analyses during coating thermal degradation were also carried out to explore the outstanding synergistic smoke suppression and flame retardancy mechanism of ZB and Sb2O3. With the melt of ZB and Sb2O3, a lot of heat was absorbed, and then, the glassy protective layer associated with the graphite char would effectively retard heat and suppress smoke.

The protective effects and aging process of the topcoat of intumescent fire-retardant coatings applied to steel structures

The protective effects of a topcoat on an intumescent fire-retardant coating were studied under hydrochloric acid solution corrosion, accelerated UV aging and natural weathering. The protective effects were determined to be appreciable under all the aging conditions. During hydrochloric acid corrosion testing, the coating sample without the topcoat exhibited no fire resistance after immersion for 48 h. When a topcoat was used, the acid solution could not directly corrode the fire-retardant coating. However, the solution was observed to seep into the coating layer from the edges, demonstrating that special attention must be paid to the edges and corners to avoid the pollution source corroding the coating and substrate. Under the accelerated UV aging conditions, the fire-resistant properties of the unprotected coating deteriorated significantly after 20 days of aging due to the hydrolysis and photooxidation of the components. However, the coating with a topcoat exhibited better fire-proof properties, even after 40 days of aging. During the natural weathering process, the fire resistance of the coating without a topcoat significantly decreased after being exposed to the high levels of precipitation and UV radiation that occur during summer. The fire-resistant properties were completely lost after 1 year of aging exposure. However, the protected sample exhibited no distinct changes in the duration of fire resistance. The results of this study remind engineering personnel to pay attention to the deterioration of the coating properties and to take protection measures. Despite slightly decreasing the fire resistance performance and increasing the cost, the protective effect of the topcoat was remarkable. Therefore, a compatible topcoat is considered indispensable for fire-retardant coatings used outdoors to ensure the best long-term fire resistance performance.

Retraction of “Synergistic Effect of Expandable Graphite and Lanthanum Cerium Oxide on Intumescent Fire Retardant Coating for Structural Applications”

Intumescent fire retardant coatings (IFRC), as a passive form of fire protection, are extensively used by the oil and gas industries to protect steel against corrosion and fire. In this study, an epoxy based IFRC was prepared with different flame retardants. IFRC was reinforced with lanthanum cerium oxide (LCO) to study its effect on thermal insulation before and after immersion in salt water for a period of one month. Characterization techniques include FESEM with EDS, TGA, XPS, XRD,and Pyrolysis GC-MS. Results demonstrated that coating with 4 wt % LCO and 3 wt % EG provided better thermal insulation both before and after salt water immersion and exhibited less weight loss as per TGA analysis.

Development and Testing of Intumescent Fire Retardant Coating on Various Structural Geometries

Materials are prone to fire and in modern construction their protection from fire is required. In any structure, various joints such as T-joint, I-beam and elbows are used. The geometry of the component has significant role in protection of structure. A weak joint may lead to failure of main structure. In order to meet these challenges, Intumescent fire retardant coating (IFRC) were developed and tested on various structural geometries such as T-joints, elbows, I-beams and pipe. The control coating formulation (IFC-C) was developed from main ingredients; Ammonium Polyphosphate (APP), expandable Graphite (EG), Melamine (Mel), Boric Acid (BA) mixed with bisphenol A epoxy resin and polyamide hardener. Another set of formulations containing various percentage of aluminium Tri-Hydrate (ATH). Fire test results of ATH based formulation showed that I-beam geometry showed the high expansion of 19 mm. T-joint showed the average surface temperature of 55°C after one hour of Bunsen burner test. The X-ray Diffraction (XRD) showed the presence of boron oxide, boron phosphate, sassolite and aluminium oxide in IFC-ATH5 residual char. The 5wt% ATH filler in IFC-C enhanced the fire protection performance of intumescent fire retardant coating formulation.

Experimental Study of the Acid Corrosion Effects on an Intumescent Coating for Steel Elements

Acid corrosion may cause the deterioration of the fire resistance of the intumescent fire retardant coatings. This paper reported the results of an experimental study of degradation in fire protection performance of intumescent coating for steel elements after different times of immersion in the hydrochloric acid solution. The morphology, the equivalent thermal resistance, and the changes of the elements and groups contained on the surface of the coatings were investigated. The corrosion mechanism was as follows: when the coating was immersed in the acid solution, the ammonium polyphosphate (APP), pentaerythritol (PER), and melamine (MEL) underwent the process of acid catalyzed hydrolysis, dissolution, and chemical reaction, which led the change of the content ratio of the compositions and caused the deterioration of the coating fire resistance. A prediction method of the remaining fire resistance property for the acid corrosion coatings was proposed, by comprehensively considering the physical and chemical characteristic changing trends of the corroded coating.

Thermal performance of alumina filler reinforced intumescent fire retardant coating for structural application

In the modern construction, fire safety has significant consideration for the protection of people and assets. Several intumescent fire protection systems are in practice and have constrain of releasing toxic gases on degradation forms an insulating char layer protecting underlying substrate. An intumescent coating expands many times of its thickness on exposure to fire and protect the underlying substrate from fire. This study presents the results of thermal performance of an intumescent fire retardant coating (IFRC) developed for structural application. IFRC was developed using expandable graphite (EG), ammonium poly phosphate (APP) and melamine (MEL), epoxy resin Bisphenol-A (BPA) and hardener triethylenetetramine (TETA) were used as a binder as a curing agent. Char expansion of IFRC was measured by furnace fire test at 450°C, thermal performance was measured using a Bunsen burner at 950°C and temperature of substrate was recorded for 60 min at an interval of two min. Results showed that IFRC containing 3wt% alumina showed char expansion X19. After one hour exposure of coating to heat, substrate temperature recorded was 154°C. X-ray Diffraction (XRD) results showed the presence of high temperature compounds present in the char of coating, considered responsible to reduce the penetration of heat to the substrate.

The Effect of Wollastonite Filler on Thermal Performance of Intumescent Fire Retardant Coating

Various types of intumescent fire retardant coatings (IFRCs) have been used to protect the substrates exposed to fire. In current study, high temperature filler Wollastonite (W) filler was used to improve fire performance of intumescent fire retardant coating. The basic ingredients of the coating were ammonium poly-phosphate (APP) as acid source, expandable graphite (EG) as carbon source, melamine (MEL) as blowing agent in epoxy binder, boric acid as additive and hardener as curing agent. In this study a range of coating formulations were developed by using different weight percentages of Wollastonite filler. The coated steel substrate samples were tested for fire performance using Bunsen burner and char expansion was measured using furnace fire test. Composition of the char was determined by X-ray diffraction (XRD) technique. The char morphology was studied using field emission scanning electron microscopy (FESEM). Results showed that Intumescent coating with addition of Wollastonite filler enhanced anti-oxidation of the char. Presence of phosphorus, calcium and silicon in char layer further improved the thermal stability of char.

Effect of Titanium Oxide on Fire Performance of Intumescent Fire Retardant Coating

The objective of this research work was to study the thermal efficiency of intumescent fire retardant coating (IFRC) designed to protect structural steel in event of fire. IFRC has been effectively developed by using ammonium polyphosphate (APP), expandable graphite (EG), melamine (MEL), boric acid (BA), titanium oxide (TiO2), and bisphenol A BE-188 with polyamide amine H-2310 as curing agent. Six formulations were developed using different weight percentage (wt. %) of TiO2 and samples were tested for char expansion in furnace at 500°C for 2 h. Bunsen burner test was used to investigate the thermal performance of coating and its performance was compared by using thermal margin value. FESEM was used for char morphology. Char composition was analyzed by XRD and FTIR. Results showed that the coating with 4 wt. % of TiO2 provides better thermal insulation to the steel substrate.

The Effect of Particle Size of Wollastonite Filler on Thermal Performance of Intumescent Fire Retardant Coating

Intumescent Fire retardant coatings (IFRC's) are one of the simplest ways to protect substrates exposed to fire. In this study, Wollastonite (W) filler of two different particle sizes were used to determine the fire performance of intumescent fire retardant coating. The basic ingredients of the coating were ammonium poly-phosphate (APP) as acid source, expandable graphite (EG) as carbon source, melamine (MEL) as blowing agent in epoxy binder, boric acid as additive and hardener as curing agent. A series of coating formulations were developed by using different weight percentages of both sized Wollastonite fillers. The coated steel substrate samples were tested for fire performance using Bunsen burner and char expansion was measured using furnace fire test. A Comparison of the coatings thermal performance was determined. Wollastonite containing filler particle size 10 µm showed better thermal performance than formulations containing filler's particle size 44 μm.

Effect of Kaolin Clay and Alumina on Thermal Performance and Char Morphology of Intumescent fire retardant coating

Intumescent fire retardant coating (IFRC) have been developed by using ammonium polyphosphate, expandable graphite, melamine, boric acid, kaolin clay and alumina as fillers bound together with epoxy resin and cured with the help of curing agent. Five different formulations were developed with and without using fillers. Cured samples were burned in furnace at 500 o C for 2h for char expansion. Bunsen burner test was performed for 1h using UL-94 vertical burning test to investigate the thermal performance of IFRC. The resultant char obtained after burning of coated samples were characterized by using field emission scanning electron microscopy for char morphology. Char composition was analyzed by using fourier transform infrared spectroscopy. Thermogravimetric analysis was carried out to investigate the residual weight of coating. Results showed that formulation with 0.5 weight % of kaolin clay and 0.5 weight % of alumina provide best thermal performance, uniform and multi-porous char structure with high anti-oxidation property.

Study and Prediction for the Fire Resistance of Acid Corroded Intumescent Coating

Acid corrosion may cause the deterioration of the fire resistance of the intumescent fire retardant coatings, especially for the coatings used in the acid polluted environment. This paper reported the results of an experimental study of degradation in fire protection performance of intumescent coating for steel elements after different times of immersion in the hydrochloric acid solution. After acid erosion, the thickness of the coating thinned, the surface became rough and had cracks and broken holes. The size of the pores in the char layer was larger and uneven, and some ‘cement’ parts were formed in the char layer. The TG/DTG results showed in the low temperature stage the curve was relatively flat. In the medium temperature stage, the number of the weight loss troughs decreased; the shape of the troughs simplified; and the top weight loss rate increased. In the high temperature stage, the troughs near 593°C flattened gradually, and the top weight loss rate became smaller, while the top weight loss rate became larger around 674°C. And there were significant changes in the thermal dynamic parameters. A prediction method of remained fire resistance property for the acid erosion coatings was proposed, by comprehensively considering the physical and chemical characteristics change trends of the corroded coating. And this method can be a reference for the fire safety evaluation of the built protected steel structure.