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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.

The epoxy resins need to be added with flame retardant to ensure safety in practical applications. There were a lot of highly toxic substances in the flame retardant used in the past, which caused greater harm to human body and the environment. Therefore, this study aims to propose a research on the synthesis of new phosphorous-containing flame retardant and the properties of flame retardant epoxy resins.

The flame retardant intermediate DOPO was synthesized using o-phenylphenol as the substrate. The intermediate was mixed with D4Vi under certain conditions to synthesize a new phosphorous-containing flame retardant. The flame retardant was added to the epoxy resins to prepare the flame retardant epoxy resins.

The experimental results show that the synthetic new phosphorous-containing flame retardant is far less harmful than the flame retardant used in the past and has extremely low toxicity, which is suitable for use in practical projects.

The new phosphorus-containing flame retardant synthesized by forms a more uniform and dense carbon layer in the combustion process, which well protects the underlying materials, thus improving the flame retardancy of epoxy resin materials. The harm of the new phosphorus-containing flame retardant is far less than that of ordinary flame retardant. The flame retardant used in the past has very low toxicity and is suitable for practical engineering.

The purpose of this paper is to prepare a novel halogen-free intumescent flame retardant (IFR) BHPPODC (benzene hydroquinone phosphorous oxy dichloride cyanuric chloride) for application to epoxy resin (EP) and study their mechanical and flame-retardant performance.

The IFR was synthesised by phenylphosphonic dichloride, hydroquinone and cyanuric chloride via solvent reaction, and the structure was fully characterised by proton nuclear magnetic resonance (¹H-NMR), mass spectrometry (MS) and Fourier transform infrared (FT-IR) spectroscopy. The thermal stability, mechanical and flame properties and morphology of the char layer of the flame-retardant EP was investigated by using thermogravimetric analysis (TGA), tensile and Charpy impact tests, limiting oxygen index (LOI) and vertical burning test (UL-94) and scanning electron microscopy (SEM).

Results of the LOI indicated that the halogen-free flame retardant as an additive exhibits very good flame-retardant effects. The results showed that the addition of IFR improved the flame resistance properties of epoxies resin composites, and the residual char ratio at 800°C significantly increased.

The IFR can be prepared successfully and can improve the flame-retardant performance.

This contribution can provide a high flame retardant performance and has minimal impact on the mechanical performance of the BHPPODC/EP composition.

This study showed that flame-retardant BHPPODC has an effective flame effect under optimal conditions. When the 12 Wt.% IFR was added to the EP, the LOI was 29.1 and the UL-94 rank can reach V-0 rank, the tensile strength was 83.86 MPa and the impact strength was 8.82 kJ/m².

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 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.

This paper aims to develop flame-retardant (FR) polyamide 12 (PA12) nanocomposite from regenerated powder via selective laser sintering (SLS), an additive manufacturing technique.

First, the morphology, processibility, thermal and mechanical properties of PA12 regenerated powder, consisting of 50 wt% new and 50 wt% recycled powder, as well as corresponding printed specimens, were evaluated to characterize the effects of previous SLS processing. Second, flame-retardant PA12 was developed by incorporating both single and binary halogen-free flame retardants into the regenerated powder.

It was found that the printed specimens from regenerated powder had much higher tensile and impact properties compared to specimens made from new powder, which is attributed to better particulate fusion and coalescence realized in higher temperature SLS printing. The effect of FRs on thermal, mechanical and flame retardant properties of the PA12 composites/nanocomposites was investigated systematically. It was found that the nanoclay, as a synergist, improved both flame-retardant and mechanical properties of PA12. UL94 standard rating of V-0 was achieved for the printed nanocomposite by incorporating 1 wt% nanoclay into 15 wt% phosphinates FR. Moreover, on average, the tensile and impact strength of the nanocomposite were increased by 26.13% and 17.09%, respectively, in XY, YZ and Z printing orientations as compared to the equivalent flame retardant composite with 20 wt% of the phosphinates FR.

This paper fulfills the need to develop flame retardant parts via SLS technology with waste feedstock. It also addresses the challenge of developing flame retardant materials without obviously compromising the mechanical properties by making use of the synergistic effect of nanoclay and organic phosphinates.

In this study, an eco-friendly cotton fabric (CF) treatment method was proposed to induce anti-ultraviolet and flame retardant properties, and a new application of tannic acid (TA) and phytic acid (PA) in ultraviolet protection and flame retardant fabric was put forward.

By combining diethylenetriamine, PA and TA on CF, a chemical reaction intumescent flame retardant CF with anti-ultraviolet and anti-flame retardance was developed.

The flame retardant and ultraviolet resistance of CF were characterized by LOI, vertical combustion, cone calorimetry and ultraviolet resistance testing. SEM, XPS, FTIR and other tests were used to analyze the chemical composition, surface morphology and residual carbon after combustion of the CF, and it was confirmed that the modified CF has good ultraviolet resistance and flame retardant performance.

In this study, an eco-friendly CF treatment method was proposed to induce anti-ultraviolet and flame retardant properties, and a new application of TA and PA in ultraviolet protection and flame retardant fabric was put forward.

This paper aims to report on the synthesis and characterisation of new flame retardants and anticorrosive additives based on Schiff’s base compounds, which were added physically to organic coating.

Flame retardants are incorporated into polymeric materials either as additives or as reactive materials. Additive-type flame retardants are widely used by incorporating into polymeric materials by physical means. In this research, Schiff’s base (azomethine) compounds are added physically to alkyd paint as flame-retardant additives. Elemental analysis, infrared spectroscopy and proton nuclear magnetic resonance spectroscopy were used to characterise the structure of the prepared Schiff’s base compounds. Thermal gravimetric analysis was used to evaluate their thermal stability. Experimental coatings were manufactured on a laboratory scale, and then applied by brush on wood and steel panels.

Results of an oxygen index value indicated that alkyd paints containing Schiff’s base compounds as additives exhibit very good flame-retardant effects. Also the physical, mechanical and corrosion resistance properties were studied to evaluate the drawbacks of the additives. The additives did not affect the flexibility of the paint formula. The gloss and the impact strength were decreased by the additives, but the hardness, adhesion and corrosion resistance were significantly improved by these additives.

Alkyd resins are the most extensively used synthetic polymers in the coating industry. Nitrogen compounds are a small but rapidly growing group of flame retardants which are in the focus of public interest concerning environment-friendly flame retardants. So, the focus of this study is on Schiff’s base compounds as flame retardants and anticorrosive additives for alkyd resins to assess their applicability.

Schiff’s base compounds can be used as new additives in paint formulations to improve the flame-retardant and corrosion properties.

In recent years, there has been considerable interest in the nitrogen-based family of materials because they not only have a wide range of thermal and chemical stabilities, but can also provide improved thermal and flame-retardant properties to polymers. The present paper reports on the synthesis and characterisation of Schiff’s base compounds and their performance in alkyd resin coatings.

In this paper, boric acid was loaded on the surface of expandable graphite (EG), polyvinyl alcohol (PVA) and silane coupling agent (KH550) served as a bridge. The purpose of this study was to improve the flame retardant properties of semi-rigid polyurethane, meanwhile, the mechanical properties of the foam got ameliorated.

PVA was dissolved in hot water. EG was added to this solution. After stirring for 0.5 h at 85°C in ultrasonic agitation, the system was put at room temperature to cool. The silane coupling agent KH550 was added dropwise into the solution system, stirring to fully hydrolyze. Boric acid was added into the system, placing it in an oven at 90°C to dry after filtration. Changing of flame retardant properties and mechanical properties of semi-rigid polyurethane adding modified EG were characterized.

The flame retardant performance of the foam with EG has been improved, whereas the tensile strength decreased with an increase in the content of EG. After adding modified EG, compared to semi-rigid polyurethane with EG, flame retardant performance and tensile strength of the foam improved.

In the study reported here, the surface of EG was modified by boric acid. The modified EG was added into semi-rigid polyurethane foam. The flame retardant performance and tensile strength of the foam after adding modified EG were discussed. Results of this research could benefit in-depth study of the influence of adding modified EG to semi-rigid polyurethane. The study could promote the application of flame-retardant polyurethane foam.

The flame retardant performance and tensile strength of the semi-rigid polyurethane were improved by adding modified EG. The effects of modified EG on the flame retardant performance and tensile strength of semi-rigid polyurethane were discussed in detail.

The potential for burn injuries arises from contact with a hot surface, flame, hot liquid and steam hazards. The purpose of this study is to develop the flame retardant acrylic and cotton blend textile finished with Enset Ventricosum pseudostem sap (EPS).

The two fabric was produced from (30% acrylic with 70% cotton) and (35% acrylic with 65% cotton) blend. The extracted sap was made alkaline and applied on two mordanted blend fabrics. The effect of blend ratio, the concentration of EPS and treatment time on flammability, Flame retardant properties of both the control and the treated fabrics were analyzed in terms of vertical flammability based on the design of the experiment software using central composite design. The air permeability and tensile strength of treated and controlled fabric were measured.

The blended fabrics at different blended ratios were flame retardant with an optimized result of burning time 2.902 min and 2.775 min and char length 6.442 cm and 7.332 cm in the warp and weft direction, respectively, at a concentration of 520 ml and time 33.588 min. There was a slight significant change in mechanical strengths and air permeability. The thermal degradation and the pyrolysis of the fabric samples were studied using thermogravimetric analysis and the chemical composition by Fourier-transform infrared spectroscopy abbreviated as Fourier-transform infrared spectroscopy. The wash durability of the treated fabric at different blend ratios was carried out for the optimized sample and the test result shows that the flame retardancy property is durable up to 15 washes.

Development of flame retardant cotton and acrylic blend textile fabric finish with ESP was studied; this work provides application of EPS for flame resistance which is optimized statically and successfully applied for a flame retardant property on cotton-acrylic blend fabric.