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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 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.

This paper aims to study a new halogen-free fame-retardant curing agent 1-aminoethylidenediphosphonate (AAEDP).

The AAEDP was synthesized by phosphoric acid, acetonitrile and ammonia. The chemical structures of AAEDP were characterized by proton nuclear magnetic resonance, mass spectrometry and Fourier transform infrared spectrometer. Thermal gravimetric analysis (TGA) and scanning electron microscope (SEM) would study the thermal properties and the char residues of AAEDP/EP. The thermal stability, mechanical and flame properties and morphology for the char layer of composite materials were separately investigated using TGA, tensile and charpy impact tests, limiting oxygen index (LOI), UL-94 HB flammability standard (UL-94) and SEM.

The results showed that the AAEDP had been prepared successfully. When the intumescent flame retardant was added into the EP, the LOI of composite material was improved.

The AAEDP can be prepared successfully and can improve the flame resistance of composite material.

The AAEDP has excellent flame-retardant properties and produce no toxic fumes when burnt in case of fire.

The results showed that the phosphorus content of AAEDP was 2.958 Wt.%; the impact and tensile strength of the composite material were 6.417 kJ m⁻² and 38.0 MPa, respectively; and the LOI and UL-94 were 29.7% and V-0 ranking, respectively. The TGA results indicated that the carbon residue ratio can be increased by 1000°C in air. The denser and more uniform structure of residual carbon prevents heat transfer and diffusion, restricts the production of combustible gas and reduces the rate of heat release.

In this paper the aim is that Aramid/alginate blended nonwoven fabrics were prepared, and the flame retardancy of the blended nonwoven fabrics was studied by thermogravimetric analysis, vertical flame test, limiting oxygen index (LOI) and cone calorimeter test.

The advantages of different fibers can be combined by blending, and the defects may be remedied. The study investigates whether incorporating alginate fibers into aramid fibers can enhance the flame retardancy and reduce the smoke production of prepared aramid/alginate blended nonwoven fabrics.

Thermogravimetric analysis indicated that alginate fibers could effectively inhibit the combustion performance of aramid fibers at a higher temperature zone, leaving more residual chars for heat isolation. And vertical flame test, LOI and cone calorimeter test testified that the incorporation of alginate fibers improved the flame retardancy and fire behaviors. When the ratio of alginate fibers for aramid/alginate blended nonwoven fabrics reached 80%, the incorporation of alginate fibers could notably decreased peak-heat release rate (54%), total heat release (THR) (29%), peak-smoke production rate (93%) and total smoke production (86%). What is more, the lower smoke production rate and lower THR of the blends vastly reduced the risk of secondary injury in fires.

This study proposes to inhibit the flue gas release of aramid fiber and enhance the flame retardant by mixing with alginate fiber, and proposes that alginate fiber can be used as a biological smoke inhibitor, as well as a flame retardant for aramid fiber.

The purpose of this paper is to investigate the potential use of the layer-by-layer (LbL) assembly as an intumescent flame retardant for polyester, cotton and their blended fabrics.

In this study, polyester (PET), cotton and their blends were applied with the flame retardant coating via the LbL assembly technique. The flame retardancy, melt dripping, thermal properties and morphology of coated polyester fabrics were then examined.

The scanning electron micrograph of uncoated and coated fabrics revealed that the LbL assembly coating on the fabric surface was successful. The assessment of the flame retardancy and thermal properties of the coated fabrics showed that the after-flame time and melt dripping during the vertical burning test decreased. The char residue at temperatures ranging from 450 to 800°C during thermogravimetric analysis was enhanced as compared with the uncoated fabric. Furthermore, the morphology of the char residual of coated fabrics was rougher and bulkier than the uncoated fabrics, suggesting the typical behavior of intumescence.

The LbL technique generally uses much fewer chemicals, thus making this flame retardant finishing much more environmentally friendly. It is also expected that these fabrics will show better touch characteristics. These fabrics may be tested for their comfort compared to that of conventional coating to enable their use on an industrial scale.

This work demonstrated the ability to apply an effective intumescent coating on polyester, cotton and blend fabric. In order to maintain fabric handle property, the Lbl coating technique is also employed.

This paper aims to discuss how acrylic resin influences the smoke generation of intumescent flame retardant coatings.

Thermal decomposition kinetics is used in this study to simulate the burning process. The thermal decomposition of acrylic resin can be identified in the intumescent coatings through the multi-peak fitting of derivative thermogravimetric (DTG) curves. The dormant influence of acrylic resin, combined with the smoke density, is calculated.

Multiple peaks fitting method of DTG curves helps estimate the decomposition process of acrylic resin in flame retardant coating. Combining DTG data with the smoking curve, smoking generation of acrylic resin during the combustion could be evaluated. The decomposition conversion rate of acrylic resin is 21.13 per cent. Acrylic resin generates 34.64 per cent of the total amount of smoke produced during the combustion of intumescent flame retardant coatings.

All the other intumescent flame retardant coating systems could be studied using the same approach as that used in this work to achieve an improved understanding of the smoke generation process during combustion.

The method developed here provided a simple and practical solution to analyse the decomposition and smoking generation of acrylic resin in the coating mixtures. It also can be used to analyse any thermal decomposition process of any mixed compounds.

The analysis method to evaluate resin’s smoking generation of coating’s total generation is novel, and it could be applied in all kinds of coatings and mixtures to estimate the smoking generation of one composition.

The cotton and its blends is the most commonly used textile material in the design and production of protective clothing. However, as the cellulose textiles are the most flammable materials it is necessary to improve its flame retardancy. The government regulations have been the driving force for developing durable flame retardants finishes for textile, to improve its performance and to reduce the negative impact on the environment. The paper aims to discuss these issues.

This paper investigates the effect of silica precursor (tetraethoxysilane – TEOS) added in bath with conventional flame retardant urea/ammonium polyphosphate in full and half concentration for achieving environmental-friendly cotton flame retardancy. Silica precursors have excellent thermal stability and high heat resistance with very limited release of toxic gases during the thermal decomposition. Synergistic effect between urea/ammonium polyphosphate and TEOS has been calculated. Thermal properties of treated cotton fabrics were determined by limiting oxygen index (LOI), thermogravimetric analysis (TGA) and microscale combustion calorimeter (MCC).

TEOS, significantly improves the flame retardancy of cotton when added in the bath with conventional flame retardants urea/ammonium polyphosphate by increasing the LOI values and other thermal properties as increasing char residue measured by TGA and higher heat release rate measured by MCC.

This paper represent a good synergistic effect between urea/ammonium polyphosphate and TEOS. This phenomena is evident in better thermal properties when TEOS was added in the bath with conventional flame retardant especially for half concentration of urea/ammonium polyphosphate.

In order to find an appropriate method to synthesize a new high-efficiency flame retardant for epoxy resin.

In this work, a flame retardant with heterocyclic groups, HOMP, was acquired after removing the obstacle from triazines which was not readily soluble. The molecular structure, thermal and flame retardant properties were fully characterized and analyzed. Also, the mechanism was researched through multi-methodologies. As well, the authors evaluated the effects of HOMP on mechanical properties.

The results suggested that HOMP helped extinguish the combustion of specimens and could reach an LOI value of 29.2% and the V0 level in the UL-94 test with a phosphorus content of only 0.6wt%. With respect to the mechanism, HOMP was a gas-phase flame retardant and helped generate a thicker carbon protective coating. However, for the mechanical properties, the addition of HOMP enhanced the compressibility, while the tensile strength decreased significantly.

The approach not only simplified the operations but also obtained HOMP with excellent flame retardant properties.

The purpose of this study is to manufacture composites from sawdust and polymer high-density polyethylene (HDPE) with different loading from alum as natural and cheap flame retardant and subsequently characterized using standard analytical tools.

Artificial wood plastic composites (WPCs) were prepared by mixing HDPE with sawdust as a filler with constant ratio (2:1) using hot press. Polyethylene-graft-maleic anhydride (PE-g-MAH) used as a coupling agent between two parents of the composites with different ratios (2.5, 5, 7 and 10). Alum as a flame retardant was incorporated into HDPE with 5 phr polyethylene grafted with maleic anhydride (PE-g-MAH) with different ratios (10, 15 and 20). Flame retardant efficiency was investigated using differential scanning calorimetry, thermal gravimetric analysis and the technique of ASTM E162.

The results revealed that the composite containing 5 phr from (PE-g-MAH) exhibited higher mechanical properties and this proved that (PE-g-MAH) act as an efficient coupling agent using the aforementioned ratio. The results also revealed that incorporation of alum as a flame retardant increased the thermal stability of the composites.

Artificial WPCs are ecofriendly materials with a wide range of applications in the constructions field. Moreover, they have high mechanical and physical properties with low cost. Evaluate alum as a natural and cheap flame retardant.

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.