Flame Retardant Agent Research Articles

Synthesis of a Novel Halogen-Free Intumescent Flame Retardant Agent

A novel non-halogen intumescent flame retardant agent (IFR) was prepared by using phosphoric acid, pentaerythritol and aniline as raw materials. The structure and thermal stability of IFR were investigated by means of Fourier transform infrared spectroscopy (FTIR) and thermogravimetric analysis (TGA). The flame retardant properties of IFR were investigated based on its inflation and char yield performance at 500°C. The results show that both the reaction time and mole ratio of raw materials have effects on the inflation and char yield of IFR.

Synthesis, Application of a Novel Halogen-Free Intumescent Flame Retardant Agent for Poplar Wood Veneer

A novel non-halogen intumescent flame retardant agent (IFR) was prepared by using phosphoric acid, pentaerythritol and aniline as raw materials, a flame-retardant poplar wood veneer was prepared by treating the veneer with IFR. The influence factors of flame retardant processing technology on poplar wood veneer were studied by the orthogonal experiment. Flammability of the veneer was investigated by Limit Oxygen Index (LOI) test. The optimal impregnated time, impregnated temperature and impregnated concentration of IFR treated poplar wood veneer were 3h, 80°C and 18% respectively, which can make the veneer get the highest LOI of 46.7%.

Flammability of polyesters

The flammabilities of a series of polyesters, varying both the diol length and the degree of aromaticity of the diacid units were evaluated using cone calorimetry. Addition of inorganic additives, copolymerization with sulfoisophthalate ionomeric units and with the phosphorous flame retarding agent, phospholane, were also examined. A strong, linear relationship between the polymer carbon:hydrogen ratio and various flammability indicators was established. The phospholane was demonstrated to produce only a modest reduction in flammability, whereas the isomeric comonomer produced an unexpectedly strong reduction in all aspects of flammability tested. Addition of inorganic modifiers resulted in varied, and relatively modest changes in polyester flammability.

Study on Thermal Decomposition Characteristics of Magnesium Salt Flame Retardants

Magnesium salt flame retardant is a new filler flame retardant agent, and can release the water and absorb the latent heat during the thermal decomposition, which can effectively inhibit the polymers decomposition and cool the combustible gas generated in the case of fire. In this paper, the magnesium salt flame retardant is synthesized in different conditions. Then the thermal decomposition features of the magnesium salt flame retardants with the smallest particle diameters are characterized by using thermogravimetric analysis and differential thermal analysis. Finally, on the basis of this analysis, optimization parameters for preparing the magnesium salt flame retardant with good thermal decomposition performance are obtained, which may be helpful for guiding the preparation of high-performance magnesium salt flame retardants and providing a beneficial reference.

Effect of Polyborosiloxane on the Flame Retardancy and Thermal Degradation of Intumescent Flame Retardant Polypropylene

A novel synergistic flame retardant agent containing boron and silicon, namely polyborosiloxane (PBSil), was prepared via the condensation reaction of boric acid (BA), tetraethoxysilane (TEOS), and octamethyl cyclotetrasiloxane (OMCTS). The obtained PBSil was then combined with an intumescent flame retardant (IFR) to flame retard polypropylene (PP), and the effects of PBSil on the flame retardancy and thermal degradation of the PP/IFR composite were investigated. It was found that PBSil could improve the compatibility between the IFR and the PP matrix, thereby improving the mechanical properties of the composite. Compared with zinc borate, zeolite, and nano-silica, PBSil showed much better flame retardancy and smoke suppression in the PP/IFR composite. When the content of PBSil was 3.0 wt%, the limiting oxygen index (LOI) value of the flame retardant PP was increased from 29.0% to 35.0%, and the UL-94 rating was improved from V-1 to V-0 rating. Simultaneously, the heat release rate (HRR) and smoke production rate (SPR) of the composite were decreased dramatically. The thermogravimetric (TG) analysis, Fourier transform infrared (FTIR), and thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR) results showed that, PBSil could enhance the thermostability of the IFR, and promote the char formation. Furthermore, the compactness and thermostability of the intumescent char were significantly improved, contributing to the improvement of the flame retardancy of the composite.

Smoke suppression properties of ferrite yellow on flame retardant thermoplastic polyurethane based on ammonium polyphosphate

This article mainly studies smoke suppression properties and synergistic flame retardant effect of ferrite yellow (FeOOH) on flame retardant thermoplastic polyurethane (TPU) composites using ammonium polyphosphate (APP) as a flame retardant agent. Smoke suppression properties and synergistic flame retardant effect of FeOOH on flame retardant TPU composites were intensively investigated by smoke density test (SDT), cone calorimeter test (CCT), scanning electron microscopy (SEM), and thermal-gravimetric analysis (TGA). Remarkably, the SDT results show that FeOOH can effectively decrease the amount of smoke production with or without flame. On the other hand, the CCT data reveal that the addition of FeOOH can apparently reduce heat release rate (HRR), total heat release (THR), and total smoke release (TSR), etc. Here, FeOOH is considered to be an effective smoke suppression agent and a good synergism with APP in flame retardant TPU composites, which can greatly improve the structure of char residue realized by TGA and SEM results.

Study of flame-retardant finishing of cellulose fibres: Organic–inorganic hybrid versus conventional organophosphonate

The aim of this study was to introduce a non-formaldehyde inorganic–organic hybrid sol–gel flame-retardant precursor (SiOP) containing phosphorous, nitrogen, and silicon and to compare its functional properties with those of the conventional formaldehyde-containing organic flame-retardant agent, organophosphonate (OP). SiOP was used at concentrations of 2%, 4%, and 8%, and OP was used at a concentration of 200 g/dm3. Both agents were applied to 100% cotton (CO) woven fabric by the pad-dry-cure method under the appropriate conditions. The presence of the SiOP and OP coatings on the CO fabric was confirmed by scanning electron microscopy, energy dispersive X-ray spectroscopy and Fourier-transform infrared spectroscopy. The results of the vertical tests of flammability and the thermogravimetric analyses showed that the presence of the SiOP coating changed the thermal degradation pathway of the CO fabric and resulted in an increase in the thermo-oxidative stability of the cellulose fibres. The thermo-oxidative stability was enhanced by the addition of higher amount of dry solids. At comparable dry solids contents, OP preserved significantly greater flame retardancy and thermo-oxidative stability than did SiOP. These results indicated that the SiOP precursor could not act as an effective alternative to the OP agent in the flame-retardant protection of CO fabric.

Thermal properties of cotton fabric modified with poly (propylene imine) dendrimers

For the first time, thermal stability and flame retardant properties of cotton fabrics modified with poly (propylene imine) dendrimer (PPI-dendrimer) using cross linking agents have been reported. The PPI-dendrimers can be considered as novel nitrogen flame retardant agents, because they contain a large number of nitrogen-containing groups (amine end groups), which may release nitrogen gas or ammonia. In this paper, the effect of the PPI-dendrimers on thermal behavior of cotton fabric is investigated through thermogravimetric analysis, differential scanning calorimetry, flammability (in vertical configuration) and limiting oxygen index tests. Indeed, both thermal stability and flame retarancy of the modified fabrics have significantly enhanced. Furthermore, field emission scanning electron microscopy micrographs have been studied in order to evaluate morphology of the cotton samples. Crystallinity and physical properties including crease recovery angle, breaking strength, whiteness index and hygroscopicity of the samples have been also assessed.

Investigation of Flame Retardant Properties of Poly(ethylene Terephthalate)/Silatrane Complex/Montmorillonite Nanocomposites

Poly (ethylene terephthalate) or PET was used in many applications such as packagings, textiles, electrical devices, and auto parts as well due to its good mechanical properties and dimensional stabilities, etc. However, the main drawback of PET is poor flame retardant and melt-dripping, which needed to be solved. Therefore, the aim of this research was to improve the flame retardant properties of PET by investigating the synergistic effects of flame retardant agents between silatrane complex and montmorillonite (MMT) at various concentrations. Silatrane complex was synthesized from silica through one pot process. The characteristic of the obtained silatrane complex was determined by FT-IR, SEM, and TGA. Various ratios of PET/silatrane complex/MMT nanocomposites were prepared by melt bending using a twin screw extruder and compressed into standard shape according to ASTM standard by a compression molding, respectively. Morphology, flame retardant properties, and mechanical properties of PET nanocomposites were investigated. The flame retardant properties were evaluated by LOI values and UL-94V rating. The results showed that mechanical properties of PET/silatrane complex/MMT nanocomposites were slightly different from those of the neat PET. The flame retardant properties showed that the LOI values of PET/silatrane complex/MMT nanocomposites were greater than that of neat PET and increased with increasing the silatrane complex concentration. The LOI value of PET/7%silatrane/2%MMT nanocomposite was increased up to 60.75%, compared with that of neat PET. While neat PET was classified into V-2 rating since it showed sustainable burning and melt-dripping behavior during burning process, PET/silatrane complex/MMT nanocomposites did not show such behavior and thus could be designated as V-0 rating. In addition, the results indicated that the MMT could occur synergistic effect with silatrane complex as well.

Aromatic phosphorodiamidate curing agent for epoxy resin coating with flame-retarding properties

Two organophosphorus-based diamines containing aromatic moieties has been synthesized and used as a curing and flame retarding agent for epoxy resin coatings. This agent functions not only as a crosslinking materials in the Epon 828 epoxy resin curing process but also as a fire retarding compound to produce thin films or composites upon curing. Phenyl phosphonic ethylene diamine diamide (PPEDD) was synthesized via condensation of phenylphosphonic dichloride (PPDC and ethylenediamine (EDA)). Likewise, phenyl phosphonic p-phenylene diamine diamide (PPPDD) was synthesized via condensation of PPDC and p-phenylenediamine (PDA). Kinetics studies of the curing reaction of the two phosphorodiamidates were carried out in comparison with the corresponding non-phosphorus containing reference crosslinking agents, EDA and PDA. Thermal stability of the cured epoxy were investigated by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). Moreover, flame retardant properties of the materials was investigated by limiting oxygen index (LOI) measurements. The results show that epoxy resin cured with phosphorodiamidate possesses higher thermostability than that of the non-phosphorus containing counterpart. This is evident by a significantly higher amount of char formed upon burning. More importantly, the LOI of 27 and 31 was observed in the PPEDD-cured epoxy resin and PPPDD-cured epoxy resin compared with those prepared from non-phosphorus curing agents (20 for EDA and 21 for PDA). This was obtained only with approximately 2–3wt.% of phosphorus content.

Polymer/clay aerogel composites with flame retardant agents: Mechanical, thermal and fire behavior

Aerogel is a class of material characterized by its high void content and extreme lightness. Different polymer/clay aerogels have been prepared by a simply freeze–thaw process from a suspension with poly(vinyl alcohol) (PVOH) and clay (Na+-MMT). Low density polymer/clay aerogels modified with flame retardant agents were prepared using a similar approach. The addition of flame retardant agents slightly increased the apparent density of the final composites whereas the compression properties were reduced due to the decrease in the polymer/clay interfacial bonding. An exception was the sample containing Al(OH)3 that exhibited higher modulus and stress at maximum deformation. Regarding thermal properties, the presence of ammonium polyphosphate (APP) or silica gel (SG) significantly slowed the rate of aerogel decomposition at the temperature range from 250°C to 500°C while the onset of polymer decomposition was not affected. Fire behavior was analyzed through cone calorimeter suggesting that either the presence of Al(OH)3 or APP reduced the heat release rate of PVOH/clay systems.

Flame retardant treatments of insulating agro-materials from flax short fibres

Improving fire resistance of lignocellulosic agro-materials is essential to extend their application domain. In this study, flame retardant agents, among which aluminium tri-hydroxide (ATH), zinc borate (ZB), melamine phosphate (MMP) and melamine borate (MMB), were incorporated in insulating materials based on flax short fibres. All flame retardant fillers were fixed firmly and permanently on the flax fibres using a protein binder. The incorporation was also homogeneous and preserved materials open porosity and expanded structure.Flame retardancy was characterized by Mass Loss cone calorimetry and UL 94 horizontal burning test. Materials morphology and thermal degradation were also investigated by scanning electron microscopy (SEM) and thermo-gravimetric analysis (TGA). Among all tested flame retardants, the best results were obtained with MMB. Immediate flame extinction was already achieved at 10 wt% loading rate, whereas the ignition time increased up to 6 times at 30 wt%, compared to the reference.

Maleic Anhydride Grafted Polymers Toughening and Flame Retardant Polystyrene Study on Modification

This study showed the effect of Decabromodiphenylethane (DBDPE) - Sb2O3、Tetramomobisphenol A (BDDP) - Sb2O3 and Mg(OH)2 to the mechanical and retardant performance. To eliminate the bad influence of flame retardant agents to materials’ mechanical performance, SEBS-g-MAH and ABS-g-MAH were added into HIPS to toughen HIPS. The experimental results showed that Decabromodiphenylethane (DBDPE) - Sb2O3 had the best effect of flame retardant, and had little influence on the mechanical performance of HIPS. SEBS-g-MAH could improve the impact strength of HIPS greatly and had little influence on other performance.

Comparison of additive and reactive phosphorus-based flame retardants in epoxy resins

The aim of this work was to investigate the effect of phosphorus-based additive and reactive flame retardants (FR) on the flammability and mechanical properties of a pentaerythritol-based model epoxy resin system cured with a cycloaliphatic diamine hardener. Commercially available ammonium polyphosphate (APP) was used as additive and 9,10-dihydro-9-oxa-10-phosphaphenantrene-10-oxide (DOPO) as reactive flame retardant. The behaviour of these systems was also compared to a recently synthesized phosphorus-containing amine (TEDAP), which can be used both as flame retardant and crosslinking agent.

Flame retardant cotton fabrics treated with organophosphorus polymer

Organo-phosphorus compounds was prepared and applied onto cotton fabrics as flame retarding agent. methacryloloxyethylorthophoshor tetraethyl diamidate (MPD) was prepared and its structure was confirmed by IR, NMR and mass spectroscopy. Pyrovatex as commercial flame retardant was used for comparative study. Impregnation method was used as coating for the application of the organophosphorus compounds to cotton fabrics. The major factors affecting the reaction were studied. The results show that the prepared organophosphorus compound can be successfully used as flame retardant for cotton fabrics.

Microencapsulation of intumescent flame‐retardant agent and application to epoxy resins

The following article from the Journal of Applied Polymer Science, “Microencapsulation of intumescent flame-retardant agent and application to epoxy resins,” by Ming Gao, Yaqi Wo, and Weihong Wu, published online on 25 August 2010 in Wiley Online Library (J. Appl. Polym. Sci. 2011, 119, 2025; http://onlinelibrary.wiley.com/doi/10.1002/app.32930/full), has been retracted by agreement between the authors, the journal's editors, and Wiley Periodicals, Inc. The retraction has been agreed because a pervasive misattribution of data resulted in fundamentally flawed experimental results, thus rendering the article's subsequent discussion and conclusions meaningless and misleading.

Effects of Adding Method of a Novel Haxogen-Free Flame Retardant Agent on the Properties of Wood-Plastic Composites

Phosphoric acid, pentaerythritol and aniline were used to synthesize a novel intumescent flame retardant agent(IFR), then IFR was added into high density polyethylene based wood plastic composites(WPC) by three different ways. Thermal degradation behavior, combustion properties and mechanical properties of WPC were evaluated by means of limiting oxygen index(LOI), thermogravimetric analysis(TGA), universal testing and scanning electron microscope(SEM) images of char formed after LOI tests. The results show that when IFR was added directly into WPC, the composite has the best flame resistant property, but the worst mechanical properties; when IFR is dissolved into solution, and the immersion method is adopted, the WPC has the best mechanical properties and better fire retardant property.

The Study on Application of N-P Intumescent Flame Retardant Agent in Waterborne Polyurethane

Phosphorylation for the first generation product of hyperbranched polymer with terminal hydroxyl (HPAE1) was carried out to synthesize a type of P-N intumescent flame retardant （HPAE1-P）, with phosphorus pentoxide and phosphoric acid as phosphorylating agent. HPAE1-P was used in waterborne polyurethane MWU-T-502B-30, and then they were tested the properties of the emulsion, such as the stability, LOI, smoke density and vertical combustion performance. The results showed that the compatibility of this flame retardant agent and waterborne polyurethane MWU-T-502B-30 was very good, and this flame retardant agent could effectively improve the polyurethane flame retardant property.

난연성 폼아스팔트 특성에 관한 연구

본 연구에서 중온아스팔트를 제조하기 위하여 우레탄폼 제조기술과 유화아스팔트 제조기술을 이용하여 폼아스팔트를 제조하였다. 화재에 약한 폼 물질과 아스팔트의 취약점을 보완하기 위하여 난연제를 첨가하여 난연성 폼아스팔트를 제조하였다. 폼아스팔트의 표피는 구멍이 뚫려 있었고 내부구조는 열린 셀의 모양을 하고 있었다. NCO%가 높을수록 폼의 강도와 셀의 크기는 증가하였다. 아스팔트는 폼의 강도를 증가시켰다. 하지만 난연제는 폼의 강도를 떨어뜨렸다. 사용된 3가지 난연제(멜라민, 디메틸포스포네이트, 트리토릴포스페이트) 중에서 멜라민이 가장 난연효과가 적었고 트리토릴포스페이트가 가장 효과가 크게 나타났다. This study was carried out to prepare a type of warm mix asphalt. Through urethane foam and emulsion asphalt preparation techniques a protocol of asphalt foam was made. Then three kinds of flame retardant agents were added in there to alleviate the inherent susceptability of asphalt and foam material to flame and thus flame retardant asphalt foam was made. The internal structure of form asphalt was composed of open cell. The higher the NCO% brought the larger the cell and the stronger also. Asphalt increased the strength of the foam. Among the flame retardant agents employed tritorylphosphate was the most effective.

Thermal and fire resistance of fibrous materials made by PET containing flame retardant agents

Poly (ethylene terephthalate) (PET) multifilaments loaded with fire retardants were produced via melt spinning and textiles were manufactured using the latter. The fire retardance properties of the knitted fabrics were investigated showing an important decrease of heat released with presence of phosphorous-containing chemicals (Exolit OP950). Incorporation of POSS nanoparticles in PET-OP950 systems slightly decreases the fire properties of the material but acts as good smoke suppressor with release of low toxic fumes while combustion.