Fire Protection Properties Research Articles

Is MWCNT a good synergistic candidate in APP–PER–MEL intumescent coating for steel structure?

Abstract For the first time, the effect of multi-walled carbon nanotube (MWCNT) on traditional intumescent coating is experimentally investigated through various techniques of Bunsen burner test, thermogravimetric analyses (TGA), Fourier transform infrared spectroscopy (FTIR) and field emission scanning electron microscopy (FESEM). Herein, MWCNT in two concentrations of 0.1 and 0.5% by weight is added to APP–PER–MEL intumescent formulation. The Bunsen burner test reveals that the fire protection property of traditional intumescent coating without nano-filler is better than that of coating containing MWCNT, and it is impaired with increasing the concentration of MWCNT. From the TGA results, no thermal stability enhancement is achieved for nano-coating. FESEM images demonstrate that cracks and holes are the main reasons of deterioration of the nano-based coatings. As a result, although MWCNT was introduced as an effective flame retardant in polymer nanocomposites, the use of this filler is not recommended in intumescent coatings for steel substrates.

Influence of molecular weight of PEG on thermal and fire protection properties of PEPA-containing polyether flame retardants with high water solubility

Abstract A series of novel PEPA-containing polyether (PAPEG) flame retardants with high water solubility were synthesized by pentaerythritol phosphate (PEPA), phosphorus oxychloride (POCl3) and polyethylene glycol (PEG) with different molecular weight. Their chemical structures were confirmed by 1H nuclear magnetic resonance spectroscopy (1H NMR) and Fourier transform infrared spectroscopy (FTIR). The influence of molecular weight of PEG on the thermal property of PAPEGs was investigated by thermogravimetric analysis (TGA) and a possible thermal degradation mechanism was speculated to illustrate the char-forming ability of PEG. Afterwards, the influence of molecular weight of PEG on the fire protection of the transparent fire resistant coatings (FRC) was investigated in detail by fire protection test, intumescence ratio, scanning electron microscopy (SEM) and TGA. The fire protection test found that the coatings with low molecular weight PEG presented good fire retardancy, supplying effective fire protection for the plywood boards. The intumescence ratio and SEM results well demonstrated that the fire protection of coatings and foam structure of char layers were significantly improved when the molecular weight of PEG was low. TGA result showed that the residual weights of the fire resistant coatings presented the order of FRC200 > FRC150 > FRC400 > FRC600. It indicated that low molecular weight PEG could enhance the char-forming ability of the coatings. TGA and real-time FTIR results proved that blowing agent and carbon source degraded in the same temperature range, which resulted in the formation of intumescent char layer.

Influence of hybrid functionalized graphite nanoplatelets-tripolyphosphate on improvement in fire protection of intumescent fire resistive coating for steel structures

Functionalized graphite nanoplatelets (FGNP) were modified with tripolyphosphate (TPP) as a thermal oxidation inhibitor. The hybride nano-particles (FGNP-TPP) effects on improvement of fire retardant properties of a traditional intumescent fire retardant (IFR) formulation were investigated. FT-IR results showed that TPP was linked to FGNP nano-particle by hydrogen bondings. TEM image showed homogenous dispersion of FGNP-TPP nano-particles in epoxy. Thermogravimetric analysis (TGA) in air showed the oxidation onset temperature of FGNP was increased by approximately 125 °C in the presence of TPP. Incorporation of 2 wt.% of FGNP-TPP into the traditional IFR coating increased the LOI value from 27.1 to 32. Also, a crack free char with high adhesion to the metal substrate was observed in bunsen burner test which increased the time of failure from 43 to 94 min. The results showed the hybrid nano-particles can improve the thermal oxidation stability of the IFR coating at higher temperatures (900–1000 °C) leading to improved char strength, char adhesion, char morphology, residual weight and fire protection properties.

Oriented Clay Nanopaper from Biobased Components—Mechanisms for Superior Fire Protection Properties

The toxicity of the most efficient fire retardant additives is a major problem for polymeric materials. Cellulose nanofiber (CNF)/clay nanocomposites, with unique brick-and-mortar structure and prepared by simple filtration, are characterized from the morphological point of view by scanning electron microscopy and X-ray diffraction. These nanocomposites have superior fire protection properties to other clay nanocomposites and fiber composites. The corresponding mechanisms are evaluated in terms of flammability (reaction to a flame) and cone calorimetry (exposure to heat flux). These two tests provide a wide spectrum characterization of fire protection properties in CNF/montmorrilonite (MTM) materials. The morphology of the collected residues after flammability testing is investigated. In addition, thermal and thermo-oxidative stability are evaluated by thermogravimetric analyses performed in inert (nitrogen) and oxidative (air) atmospheres. Physical and chemical mechanisms are identified and related to the unique nanostructure and its low thermal conductivity, high gas barrier properties and CNF/MTM interactions for char formation.

Selection of the fire detectors and their arrangement in object

The appearance of fire in objects, especially in objects with lot of humans inside represents very possible real situation that could be very danger and could cause destructive consequences on human lives and material properties. Very important task in fire protection, human and material properties safety could be a proper adoption of fire detectors and theirs disposition in object. The right type of fire detectors, with theirs disposition and density has to provide right time reaction, with minimal occurrence of false alarms and acceptable price. There are many different factors for fire detectors selection. On the other hand, there are several standards for fire detectors disposition. This facts show that good projected fire protection sys­tem must satisfied a lot of different and important tasks. This paper presents representation of fire detectors, their selection according to the different factors, theirs disposition in object according to proper standards and simula­tion in PyroSim software as an evidence for noted facts.

Investigation on solvent-borne intumescent flame-retardant coatings for steel

This paper presents an investigation on solvent-borne intumescent flame-retardant coatings that can provide good bonding strength, water resistance and fire protection to the steel substrate. The fire protection performance and characterisations of the coatings were investigated by using the Bunsen burner test, thermogravimetry analysis, field emission scanning electron microscope, static immersion test and Instron Micro Tester. It was found that the fire protection and foam structure of the coating significantly improved by adding the combination of Mg(OH)2 and TiO2 flame-retardant fillers to the flame-retardant additives and acrylic binder. The formation of uniform foam structure and reaction of the coating which decompose into voluminous and multi-cellular char layers with thermal insulation properties contribute an important fire protection to the steel substrate from reaching its critical temperature. However, the combination of [Al(OH)3 and Mg(OH)2] flame-retardant fillers to the flame-retardant additives and epoxy binder led to maximum adhesion strength. The improvement in the bonding properties of the coating to the metal surface was attributed to the effective [Mg(OH)2 and TiO2] fillers/epoxy binder interface adhesion. Hence, the findings of this study reveal that the selection of appropriate combination of binders and flame-retardant fillers strongly influenced the fire protection, water resistance and mechanical properties of intumescent coatings.

Influences of flame-retardant fillers on fire protection and mechanical properties of intumescent coatings

a b s t r a c t A combination of acrylic binder and flame-retardant ingredients was used to synthesize the solvent-borne intumescent coatings designed for steel substrates. The influences of individual and various combinations of flame-retardant fillers on the fire protection and mechanical properties of the coatings were character- ized by using Bunsen burner, thermogravimetric analysis, limiting oxygen index, field emission scanning electron microscopy, freeze-thaw cycles, static immersion and pull-off type equipment. It was found that the combination of aluminium hydroxide (Al(OH)3) and titanium dioxide (TiO2) has significantly improved the fire protection, thermal stability and water resistance of the coating. This formulation had an LOI value of 34, which indicated good flammability resistance of the coating. The adhesion strength tests showed that the coating added with magnesium hydroxide (Mg(OH)2) exhibited maximum bonding strength to the metal surface due to its effective interface adhesion. Hence, the findings from this study revealed that the selection of appropriate combinations of flame-retardant fillers strongly influenced the physical and chemical properties of the coatings.

Fire Protective Properties of Durisol Construction

Fire Protective Properties of Durisol Construction

The importance of fire simulation in fire prediction

The appearance of fire in objects with lot of humans inside represents very possible real situation that could be very danger and could cause destructive consequences on human lives and material properties. Very important influence in fire prediction, fire protection, human and material properties safety could be a fire simulation in object. This simulation could give many useful information of possible fire propagation; possible and existed evacuation routes; possible and exited placing of fire, smoke, temperature conditions in object and many other information of crucial importance for human lives and material properties, such as the best places for sensors position, optimal number of sensors, projection of possible evacuation routes etc. There are many different programs for fire simulation. This paper presents complete fire simulation in Electrotechnical school Nikola Tesla in Niš in FDS.

Multi-attribute Decision-making in Economics of Fire Protection

The economic decisions concerning fire safety of built property may involve alternative solutions (alternatives) of fire protection measures, comparison of buildings with different fire safety levels, choice among construction products with different properties of performance in fire. The need to choose among alternatives may be faced by various interested parties: fire safety regulators (authorities on national level), insurers, architects (building designers), manufacturers of fire protection measures, property owners and buyers. The problem of choice will often involve the need to consider simultaneously several characteristics (attributes) of alternatives, and those related to fire safety will be accompanied by economic and non-economic ones. Such a choice can be formalised as a problem of multi-attribute selection (MAS), a filed known also as multi-criteria decision making (MCDM). The present paper aims to formulate and solve several problems of multi-attribute selection by taking into account attributes related to fire safety. The problems are considered in an attempt to facilitate decision-making on three levels: the level of a property buyer/renter, the level of a property owner, and the level of an architect (building designer). It is shown that a different level of decision making requires to apply attributes of different nature. The well-developed field of fire safety offers a range of quantitative and qualitative indicators describing fire performance of building materials, construction and fire protection products as well as entire buildings. These indicators are introduced, with relative ease, into MAS problems. The attributes of economic nature fit naturally in the MAS problems involving fire safety. They can be introduced passively and accompany fire-related attributes as well as other non-economic attributes. However, economic aspects of MAS problems can be used in a more subtle way, namely, by introducing elements of formal expression of risk posed by fires. Monetary losses caused by fires are among the elements of a risk profile. An expected value of these losses can be used as an MAS attribute.http://dx.doi.org/10.5755/j01.ee.22.3.516

Testing fire protective properties of intumescent coatings by in-line temperature measurements on a cone calorimeter

An experimental setup was proposed for evaluating the thermal shielding efficiency of intumescent coatings. In particular, a cone calorimeter as heater source was coupled with a thermocouple as detector of the temperature of steel plates coated with intumescent coatings. According to ENV 13381-4 test procedure, the heating curves of the setup was measured by plate thermocouple and compared with ISO 834 standard curve. Meanwhile, the comparison was also made between temperature profiles of blank steel plates at different heat fluxes and unprotected steel elements under ISO fire. The possible correlation between bench scale and large scale test was hence discussed. Several factors (heat flux, distance to cone heater, coating thickness, sample size, edge effect and heat insulator) were deeply investigated and discussed: significant relationships between these parameters and the thermal protective properties of the intumescent coating were evidenced; furthermore a fully developed intumescent char could be obtained by controlling the aforementioned parameters. As a conclusion, the proposed bench-scale test was found to be comparable to the large scale test only in the early heating stages.

Experimental study on the fire protection properties of PVC sheath for old and new cables

The objective of the present study is to analyze the fire protection properties of old and new cables through TG, FTIR and MCC experiments. The results show that the mass loss of old cable sheath is clearly larger than the new one when the temperature is higher than 550 K in air or nitrogen atmosphere. It suggests that the old cable sheath starts to pyrolyze generally at the same temperature based on the analysis of the onset temperatures of mass loss. The results also show that there is a main peak DTG for the old and new cable sheath under each condition. However, the main peak DTG of old cable sheath is larger than that of the new cable sheath, especially in air atmosphere. The FTIR experiments show that the HCl is released by the new cable later but more quickly than the old cable. The MCC experiments suggest that compared with the new one, the peak heat release rate is larger for the old cable. It illustrates that the old cable sheath generally pyrolyzes and combusts more strongly and completely than the new one. Namely, the fire protection properties of the old cable in old buildings are relatively weak.

Influences of binder on fire protection and anticorrosion properties of intumescent fire resistive coating for steel structure

The combination of epoxy emulsion and self-crosslinked silicone acrylate (SSA) emulsion was used as mixed binder for preparing water-borne intumescent fire resistive coating. The influences of binders on the properties and char formation of the coatings were investigated in detail by using thermogravimetry (TG), scanning electron microscope (SEM), X-ray diffraction (XRD), X-ray fluorescence spectrometry (XRF), rheological measurement, fire protection test and anticorrosion property test. It was found that the fire protection and foam structure of the coating was significantly improved by adding 14% SSA (by mass). The TG results showed that adding SSA increased the residue weights of the coatings. The XRF results demonstrated that anti-oxidation of the coatings was improved by adding SSA into the mixed binders. The results of anticorrosion property test indicated that the anticorrosion property of the coatings was enhanced with increase of content of SSA.

Effect of acrylic polymer and nanocomposite with nano-SiO 2 on thermal degradation and fire resistance of APP–DPER–MEL coating

Acrylic nanocomposite and flame retardant coatings with different acrylic polymers were prepared. The effect of molecular structure and molecular weight of acrylic resins and nanocomposite with nano-SiO 2 on the interaction and char formation of ammonium polyphosphate–dipentaerythritol–melamine (APP–DPER–MEL) coating was investigated using differential thermal analysis (DTA), thermogravimetry (TG), Limiting Oxygen Index (LOI), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and fire protection test. The interaction of APP, DPER, MEL and 3F-1 acrylic resin led to the formation of intumescent coherent char at 300–450 °C. Owing to low molecular weight and lack of benzene rings, F-963 acrylic resin decomposed at lower temperature than APP, and hence their endothermic interaction was destroyed. The well-distributed nano-SiO 2 particles in acrylic nanocomposite could modify char formation and anti-oxidation of char structure at high temperature. It is noted that the fire protection properties of nanocoating with acrylic nanocomposite were better than those of flame retardant coatings with conventional acrylic resins.

THERMAL DEGRADATION ANALYSIS OF WOOD TREATED WITH FIRERETARDANTS

Fire hazard control in wooden constructions is very important. For this purpose, fire retardants are used, which change the thermodestruction of wood and reduce combustion. The aim of the present research project was to study and compare the fire–protective properties of fire-retardants and to explain the chemical process of pyrolysis, namely, degradation in treated and untreated wood. The influence of fire-retardants on the wood thermal stability and the amount of volatile products was estimated on the basis of thermal analysis results. The volatile products (above 50%) of the pyrolysis process were identified, and the mechanism of the influence of fire-retardants on wood thermodestruction was studied.The presence of toxic compounds, formed by pyrolysis, was evaluated. The results of the study have shown that analytical pyrolysis is a modern, precise method for identifying the toxic compounds of volatile products in processes of both wood pyrolysis and combustion. The application of analytical pyrolysis enables a prompt determination of the fire protection degree of building wood constructions.

Development of polymer–ceramic composites for improved fire resistance

Materials that provide protection of lives and property from fire are highly desirable across many industries. Conventional polymers are generally completely consumed in a fire situation and require either halogenated additives that give off toxic and corrosive gases with large volumes of smoke or high filler loadings of non-halogen based additives in order to impart fire resistance. Attention has been shifted to the area of “ceramifiable” polymers as a means of improving passive fire protection, and silicones have been shown to possess desirable properties on firing, such as a slow burning rate without a flaming drip and low emissions of non-toxic smoke. However, the ceramic formed by firing silicones alone is very weak and powdery. Addition of certain inorganic fillers improves the strength, giving a near-net shape ceramic. The fire protection properties of silicone and silicone-based composites are investigated at temperatures up to 1100°C. The microstructure of the resultant ceramics has been studied and the mechanism for the conversion of silicone-based composites to ceramics is proposed.

Effect of fillers on the fire retardancy of intumescent polypropylene compounds

The effects of fillers (talc and calcium carbonate) were investigated on polypropylene /ammonium polyphosphate/polyamide-6 (PP/APP/PA-6) intumescent system by using mechanical testing, LOI method, cone calorimetry and thermoanalytical techniques. Calcium carbonate and talc affect the fire protective properties of PP/APP/PA-6 system in different ways. It is shown that talc induces an increase in the Young's modulus and a decrease in the elongation at break. Calcium carbonate leads to a decrease in the elongation at break, but there is no improvement in the Young's modulus. Talc increases fire protective performance due to forming a ceramic like protective shield at the surface, whereas calcium carbonate decreases it because of a reaction with APP. Effects of talc and calcium carbonate were furthermore investigated on PP/APP/PA-6 system by measuring Rate of Heat Release (RHR), Total Heat Emitted (THE), CO/CO 2 evolution and residual mass. Results are interpreted by means of decomposition, chemical reaction between components and formation of a protective shield at the surface at ignition.

PIPD, a new high‐modulus and high‐strength polymer fibre with exceptional fire protection properties

AbstractThe development of the new high‐modulus and high‐strength fibre M5, made of poly{2,6‐diimidazo[4,5‐b:4′,5′‐e]‐pyridinylene‐1,4(2,5‐dihydroxy)phenylene} or PIPD, has resulted in an organic polymer fibre with exceptional fire protection properties when compared with PBO, Twaron, Kevlar and Nomex fibres. The PIPD as‐spun fibre with a modulus of 150 GPa and a tensile strength of 2.5 GPa is a crystal hydrate containing 21 wt% water. Cone calorimeter measurements yielded a fire performance index (FPI) 20 times higher than Nomex, with extremely low value for the specific extinction area (SEA) characterizing the smoke formation. The PIPD‐HT fibre (recrystallized in an after treatment into the anhydrous crystalline structure) with a modulus >300 GPa and a strength >5 GPa has a FPI value similar to PBO but shows much less smoke formation than this fibre. Copyright © 2002 John Wiley & Sons, Ltd.

Thermal Stability and Flammability of Sulphochlorinated Polyethylene Compositions

Abstract The effect of some metal oxides used as nonactive fillers and fire retardant system components on thermal characteristics and flammability of sulphochlorinated polyethylene was studied. The flammability of compositions was estimated by the limiting LOJ method under standard conditions and also in the case of flame spreading in the horizontal direction and in the vertical one upwards. Temperature profiles in a burning wave were determined with the help of a thermocouple probe for optimum composition. Heat flows from the flame to the polymer surface were calculated. A materials fire-protective properties were estimated by the thermal shock method with single-side heating. The mechanism of a materials fire-protective effect was discussed.

Investigation of phosphorus-containing foam-forming systems as combustion retardants for polypropylene

Foam-forming systems based on ammonium polyphosphate, pentaerythritol and melamine, as well as other systems, have been investigated as combustion retardants for PP. The effectiveness of a system is determined principally by the ratio of the weight fractions of phosphorus, CH 2O—and amino groups. Such properties of the coke as the volume change on foaming, the coke residue and the porosity also depend on this ratio; the fire-protection properties depend, in their turn, on these properties. The fire resistance of compositions depends principally on the mass of the coke-foam formed, whereas the volume change on foaming has a considerable effect upon the resistance only at small values.