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The purpose of this paper is the production of fire retardant and smoke suppressant rigid polyurethane foam (RPUF) with lower toxicity by using several fire-retardant combinations.

Fire-retardant additives with cooling effect, barrier ash formation effect, gas-phase inhibition effect and smoke suppressant effect combined to produce an optimum outcome on RPUF. The additive amount and burning time correlation were studied to find out the minimum amount of fire-retardant to obtain fire-retardant polyurethane foam.

Zinc borate powder was coated with 1.5 wt % of stearic acid and hydroxy stearic acid. Polyammonium diborates (PABs) were synthesized and used as a fire-retardant and smoke suppressant for rigid PU foam. Fire-retardant rigid polyurethane foams (FR-RPUF) composites formed by using several combinations of zinc borate, aluminum trihydroxide, trischloroisopropyl phosphate (TCPP), PABs, zinc borate coated with stearic acid and hydroxy stearic acid. Produced FR-RPUF were horizontal burning grade, and burning time was in the range of 1–10 s.

There were limitations during the mixing of fire-retardant powders with polyol due to the high viscosity of the mixture.

FR-RPUF foam with lower toxicity can be produced industrially with these fire-retardant combinations.

FR-RPUF could be produced by using non-toxic additives. During a fire, these additives do not evolve toxic gases. The TCPP content of RPUF foam was reduced, and fire-retardant PU with lower toxicity was produced.

Coated zinc borate and the combinations of the fire-retardants were successful in producing non-toxic fire-retardant and smoke suppressant PU foam.

The fire safety of structures is an existing and important design aspect, which is assured by strict regulations. As a means to adhere to the strict requirements, fire protection has become a core problem. It is particularly difficult to comply with these regulations in the case of timber, which is a combustible material. These problems could be solved by enveloping the wood in fire retardant materials. MSZ EN 1995-1-2 currently does not take into consideration the fire-retardant materials charring rate under fire exposure.

However, currently these fire retardants are proving to be reliable and depending on their application can achieve better reaction-to-fire classifications. During the research, the authors used five different fire-retardant materials on three different types of wood and tested their behaviours in a laboratory. When selecting them, it was important to choose the species that are most commonly used in the building industry but which have significantly different densities. Our choice fell upon spruce (360 kg/m³), Scots pine (540 kg/m³) and oak (650 kg/m³). During the tests, we examined the weight reduction and the process of burning on the specimens treated with the fire retardant material. In addition, the authors also performed tests by derivatography on both untreated and treated specimen.

The question is whether the effects of the fire retardants should be taken into consideration when calculating the extent of the burn. The Eurocode (MSZ EN 1995-1-2) does not provide any opinions. On the market, there are manufacturers who are already discussing the possibilities of reducing the burn rate during the qualification of paints. In this paper, based on the results we received, we discuss the beneficial effects of the fire retardants which can be taken into account while measuring cross-sections.

By using fire retardants, a high proportion of cross-sectional area gain is only possible in case of small cross-sections; therefore, it is advisable to use them here as well. This can be effective for example in many smaller cross-sections, when there is a little space and therefore requires a small cross-section. Thus, if a larger cross-section without protection is not possible, it can be replaced by a smaller cross section, treated with a fire retardant.

Fire protection regulations are difficult to comply with in the case of wooden structures because of the fact that wood is a combustible material. The fire protection of wood can be solved with coatings or by the application of flame retardants.

The standard of MSZ EN 1995‐1‐2 currently does not allow the consideration of fire retardants in case of scaling the fire load. In spite of the aforementioned, today there are many types of retardants on the market that are reliable and allow us to achieve a better fire protection classification.

The question is how sensitive a wood preservative is to a construction fault, or what would be the result of the erroneously applied fire retardant to the fire protection characteristics of timber used in constructions.

During the research, five different fire retardants were tested on three types of wood and their behaviour was monitored under controlled laboratory circumstances. When selecting the wood, it was important to take the wood species that are most commonly used in the construction industry, and their density should be as different as possible. During the tests, the wood preservative was applied incorrectly, modelling the following cases: applying less or more wood preservatives, and creating small and large faults.

This paper aims to examine the fire retardant property potentials of cow horn ash particles (CHAp) bio-additive and aluminium trihydrate (AH), a traditional inorganic fire-retardant additive, respectively, in banana peduncle fibre (BPF) reinforced polyester composites. An attempt was made to comparatively analyse the fire retardant capacity potentials of CHAp, a bio-material waste that is readily available, at no cost, as a potential fire retardant material for composites manufacture with a conventional inorganic fire retardant additive (AH).

The fibre used in this research was derived from the banana peduncle. The matrix is unsaturated polyester. A scanning electron microscope was used to analyze the particle size of the carbonized CHAp. The composites were compounded using 0%, 2.5%, 5%, 7.5% and 10% of CHAp and AH, respectively. A cone calorimeter instrument was used in the analysis to obtain combustion information of CHAp and AH formulated polyester-BPF composites. Test samples were cut to the dimensions of 100 × 100 mm. All materials are conditioned at 23 ± 30 °C and the relative humidity of 50 ± 5% for 24 h before testing. The samples were wrapped with aluminium foil around the back and edges before placing the samples on the holder and then into the cone calorimeter. The samples were backed with a non-combustible insulating refractory material (brick). The samples were orientated horizontally and exposed to irradiances of 50 kW/m² at a temperature of approximately 6000 °C. The samples were pilot ignited and ran in triplicate; the average readings of the three runs were taken.

The results obtained from the analysis depicted similar fire retardant properties for formulations with CHAp and AH, respectively. Composites formulated with CHAp exhibited delayed ignition time of 25%, increased end of burning time of 14.24% and reduced total heat release rate of 9.07% for the developed composites. The developed BPF/CHAp/polyester composites yield composites with fire retardancy, which would find relevance in the engineering material industry.

CHAp, therefore, would suffice as an alternative to the inorganic, expensive and non-environmental friendly, conventional fire retardant additives used in composites manufacture.

Fire retardant materials made of unsaturated polyester resin containing different halides and antimony trioxide were studied. In the present work the addition of a substance rich in halogen such as polyvinylchloride (PVC) and antimony trioxide Sb₂O₃ to the composite made of unsaturated polyester and fiberglass as a reinforced material has been studied. The addition of fire retardant material (PVC) and (Sb₂O₃) enhanced the fire retardancy of the product with remarkable low effect on the mechanical properties of the products. The electrical properties of the products are studied.

Cyclohexanone–formaldehyde resin (CFR) was in situ modified with isocyanuric acid (ICA) in the presence of hydrochloric acid or p-toluenesulfonic acid by condensation polymerization. The purpose of this study is to produce isocyanuric acid-modified ketonic resins that have higher melting and decomposition temperature, and to use the produced resin in the production of fire-retardant polyurethane.

Two methods were used for in situ preparation of ICA-modified CFR in the presence of an acid catalyst. Method I: cyclohexanone, paraformaldehyde and ICA were mixed, and then an acid catalyst was added to form the modified CFR. Method II: ICA and formalin were mixed to produce N, N, N-trihydroxymethyl isocyanurate, and then water was removed under vacuum. The produced N, N, N-trihydroxymethyl isocyanurate solution was mixed with cyclohexanone and paraformaldehyde, then an acid catalyst was slowly added to this mixture to obtain ICA-modified CFR.

CFR was prepared in the presence of an acid catalyst. The product, CFR, has a dark red colour. The resulting resins have similar physical properties with the resin prepared in the presence of a basic catalyst. The solubility of ICA-modified CFR is much different than CFR in organic solvents.

This study focuses on obtaining an ICA-modified ketonic resin. Cyanuric acid has the form of an enolic structure under a basic condition; therefore, it cannot give a product with formaldehyde under basic conditions. The modification experiments were carried out in acidic conditions.

This study provides technical information for in situ modification of ketonic resin in the presence of acid catalysts. The resins may also promote the adhesive strength of the coating and provide corrosion inhibition on metal surfaces for a coating. The modified resins may also be used in the field of fire-retardant polyurethane applications.

These resins may be used for the preparation of non-toxic fire-retardant polyurethane foam. Polyurethane containing ICA-modified resin may exhibit better fire-retardant performance because of the incorporation of ICA molecule into the polyurethane structure.

ICA-modified CFRs have been synthesized in the presence of an acid catalyst, and the ICA-modified resin was used to produce fire-retardant polyurethane.

Fire retardant alkyd resins modified with dehydrated caster oil were prepared directly without going though the alcoholysis step. The method is based upon dehydrating castor oil with trimellitic anhydride. The oil thus produced contains sufficient combined carboxyl groups capable of polyesterifications with triols and glycerol or chlorinated monocyclic acetal and glycerol, and the macro‐structure is completed by further reaction with PA or chlorendic anhydride to obtain flame retardant resins. Melamine formaldhyde resin have been used in combination with the previous alkyd resins to improve hardness and also fire retardancy.

The purpose of this paper is to use the natural wastage plant product, bannana pseudostem sap (BPS) for using as fire retardant of cellulosic textile substrate. The study aims to use first time any wastage plant product for making fire retardant cellulosic textile. In this regard flame retardant functionality was imparted in cellulosic textile using BPS, an eco-friendly natural wastage product.

The extracted sap was made alkaline and applied in pre-mordanted bleached and mercerized cotton fabrics. Flame retardant properties of the control and treated fabrics were analyzed in terms of limiting oxygen index (LOI), horizontal and vertical flammability and total heat of combustion using bomb calorimeter. The thermal degradation and pyrolysis was studied using thermogravimetric analysis (TGA). The chemical composition of the control and BPS treated cellulosic fabric were analyzed by FTIR, SEM and EDX. Durability of the flame retardant functionality to soap washing had also been studied.

The study showed that the treated fabrics had good flame retardant property compared to control fabrics. The LOI value was found to increase by 1.6 times after application of BPS. As a result of this, the fabric does not catch flame. In horizontal flammability, the treated fabric showed burning with afterglow (without presence of flame) with a propagation rate of 7.5 mm/min, which is almost ten times lower than the control fabric. After application of BPS cellulosic fabric sample produced natural khaki colour. There was no significant change in other physical properties.

The application process is simple and cost-effective as no costly chemicals were used. Further advantage is that the treated fabric could also be considered as natural dyed cotton fabric. The developed khaki colour is quite attractive and stable to sun light exposure. This developed process could used in colouration and flame retardant finishing of home furnishing products such as home-window curtain, railway curtain, hospital curtain, table lamp and as a covering material of non-permanent structure like in book fair, festival, religious purpose, etc., where large quantity of textile is used and has chance of fire hazards.

BPS abundantly available in Indian as well as other countries and it is normally considered as waste material. It is eco-friendly and produced from renewable source. Therefore, the application of BPS in cotton textile for colouration and functionalization will give the advantages of value addition using natural product. Rural people will be benifited lot by applying this technology whenever it required.

This paper helps to clarify first time why and how a wastage plant product like BPS can be used for preparing fire retardant cotton cellulosic fabric.

Cotton fabrics can be dyed with reactive and/or direct dyes in aqueous baths under certain specific conditions of pH, salt, temperature, time, etc., and rendered fire retardant through reaction with reactive phosphonopropionamide compounds. In the presence of reactive tertiary amines and reactive phosphorous derivatives, cotton fabrics can be dyed with reactive, direct or acid dyes in the absence of the usual added alkalis and salts, and in the mean time, the fabric becomes fire retardant with wash and wear properties. To verify such claims, reactive aminating agents are synthesized by reacting different amine compounds that have various numbers of amino groups with acryl amide and formaldehyde. The pad-dry-cure technique is applied to treated fabrics with aqueous finishing formulations that contain dyestuff and reactive amine-compounds; the cotton fabric will simultaneously impart reactive dyeing, easy-care inishing and fire-retardant properties. Systematic studies show that in the presence of 6% weight/weight, reactive amine in an aqueous formulation yields cotton fabric with the least loss in tensile strength and elongation at break, and an enhancement to the crease recovery angle. By adding the dyestuff to the aqueous formulation at fixed nitrogen content for treated cotton (0.2%) under identical dyeing conditions, the colour strength (K/S) increases for dyed cotton. The fastness properties of the dyed fabric are improved or remain unaltered for the three types of dyestuffs used

This study examines the effects of using magnesium chloride as a precipitating agent of sodium silicate on the mechanical, optical and fire retardant properties of the resulting paper sheets. Two types of treatments (internal and external), were carried out to investigate such effects on the paper sheets prepared from wood pulp and from non‐wood fibrous, bagasse pulp. The results obtained showed that the treatment of paper sheets with either sodium silicate or sodium silicate‐magnesium chloride led to a decrease in the activation energy of the initial main degradation stages. Wood pulp‐paper sheets treated with sodium silicate showed better fire retardant properties than the sodium silicate‐magnesium chloride treated wood pulp‐paper sheets. A reverse trend was noted in the case of paper sheets made from bagasse pulp.