A Series of Metal Molybdates as Flame-Retardants and Smoke Suppressants for Flexible PVC

A series of metal molybdates were synthesized as flame-retardants and smoke suppressants for flexible poly (vinyl chloride). The powder of molybdates was characterized by the x-ray diffraction. The flame retardancy, smoke suppression and thermal behavior of PVC treated with a series of molybdates were studied by means of limiting oxygen index (LOI), smoke density rating (SDR), thermogravimetry (TG), differential thermogravimetry (DTG), differential thermal analysis (DTA) and scanning electron microscopy (SEM). The results shown that, the flame retardancy and smoke suppression performance of PVC samples depend on the strength of the Lewis acid which generated in the first degradation stage and the stability of residue char in the second stage. While the strong Lewis acid can also function as cracking catalysts in the second stage, and cracking of the principally hydrocarbon char can promote the generation of volatile organic compounds, which act as efficient fuels. This situation results in less smoke, but increased flame.

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Thermal Properties and Flame Retardancy of Wood Treated with a Series of Stannates

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.150-151.475 ◽

2010 ◽

Vol 150-151 ◽

pp. 475-479

Author(s):

Hong Qiang Qu ◽

Wei Hong Wu ◽

Lei Liu ◽

Jian Zhong Xu

Keyword(s):

Flame Retardant ◽

Flame Retardancy ◽

Char Residue ◽

Dehydration Reaction ◽

Second Stage ◽

The Third ◽

Degradation Reaction ◽

The Stability ◽

Differential Thermogravimetry ◽

Scanning Electron

A flame retardant wood was prepared using a series of insoluble stannates through the double bath technique. The flame retardancy of the wood samples was studied with the LOI method. The relationships between the flame-retardant performance and the thermal property of wood were studied by the thermogravimetric analysis (TGA), differential thermogravimetry (DTG), differential thermal analysis (DTA) and scanning electron microscopy (SEM) methods. The results show that the insoluble stannates, which were precipitated into the wood by the double bath technique, can obviously improve the flame retardancy of wood. Na2SnO3 can catalyze the intermolecular dehydration reaction and increase the stability and amount of the char residue, and the metal ions not only catalyze the intermolecular dehydration reaction in the second stage but also changed the degradation reaction of the char residues in the third and fourth stages.

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Zinc Hydroxystannate-Coated Mineral Grade Mg(OH)2 as Flame-Retardant and Smoke Suppression for Flexible PVC

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.652-654.481 ◽

2013 ◽

Vol 652-654 ◽

pp. 481-484 ◽

Cited By ~ 3

Author(s):

Chun Zheng Wang ◽

Wei Hong Wu ◽

Xia Ye ◽

Lei Liu

Keyword(s):

Flame Retardant ◽

Vinyl Chloride ◽

Smoke Suppression ◽

Crosslinking Reaction ◽

X Ray Diffraction ◽

Limiting Oxygen Index ◽

Smoke Suppressant ◽

Poly Vinyl Chloride ◽

Zinc Hydroxystannate ◽

The Stability

A zinc hydroxystannate-coated mineral grade Mg(OH)2 (ZHSCMH) was synthesized as flame retardant and smoke suppressant for flexible poly (vinyl chloride). The powder of ZHSCMH was characterized by the x-ray diffraction (XRD) and scanning electron microscopy (SEM). The flame retardancy, smoke suppression and thermal behavior of PVC treated with ZHSCMH and mineral grade Mg(OH)2 were comparative studied by means of limiting oxygen index (LOI), smoke density rating (SDR), thermogravimetry (TG), differential thermogravimetry (DTG) and SEM. The results show that, ZHSCMH can be used as a high effective flame retardant and smoke suppressant for PVC. The flame retardant of ZHSCMH can effectively promote the crosslinking reaction of poly (vinyl chloride) (PVC) in the first stage, and improve the stability of the char residue in the second stage.

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Flame Retardancy and Thermal Behavior of an Unsaturated Polyester Modified with Kaolinite–Urea Intercalation Complexes

Molecules ◽

10.3390/molecules25204731 ◽

2020 ◽

Vol 25 (20) ◽

pp. 4731

Author(s):

Lina Yue ◽

Junfei Li ◽

Xuan Zhou ◽

Yingjuan Sun ◽

Ming Gao ◽

...

Keyword(s):

Flame Retardant ◽

Flame Retardancy ◽

Unsaturated Polyester ◽

Smoke Suppression ◽

X Ray Diffraction ◽

Intercalation Complex ◽

Limiting Oxygen Index ◽

Intercalation Complexes ◽

Synergistic Agent ◽

Micro Morphology

Organic modified kaolinite-urea intercalation complex (KUIC) was prepared using dimethyl sulfoxide (DMSO) as the precursor of kaolinite intercalation. Its structure was characterized by Fourier transform infrared (FTIR) and X-ray diffraction (XRD). Subsequently, as a synergistic agent, KUIC was combined with flame retardant ammonium polyphosphate (APP) to improve the flame retardant and smoke suppression performance of unsaturated polyester (UP) resin. A cone calorimeter (CONE) was used to study its flame retardancy and smoke suppression, and a scanning electron microscope (SEM) and thermogravimetry (TG) were used to study the micro morphology of the char and flame retardant mechanism. The results show that 12 phr of APP and 3 phr of KUIC were doped into UP to obtain a 28.0% limiting oxygen index (LOI) value. Compared with UP, the heat release rate and smoke production of UP/APP/KUIC composites were greatly decreased. Meanwhile, KUIC indeed enhanced the mechanical properties of UP.

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The synergism of MgCO3 and 2ZnCO3·3ZnO·4H2O as flame retardants and smoke suppressants for flexible poly(vinyl chloride) (PVC)

e-Polymers ◽

10.1515/epoly.2011.11.1.906 ◽

2011 ◽

Vol 11 (1) ◽

Cited By ~ 1

Author(s):

Hongqiang Qu ◽

Weihong Wu ◽

Yunhong Jiao ◽

Jixing Xie ◽

Jianzhong Xu

Keyword(s):

Vinyl Chloride ◽

Flame Retardants ◽

Decomposition Temperature ◽

Char Residue ◽

Initial Decomposition Temperature ◽

Limiting Oxygen Index ◽

Second Stage ◽

Poly Vinyl Chloride ◽

The Stability ◽

Synergistic Agent

AbstractMgCO3 and 2ZnCO3·3ZnO·4H2O (AZC) as flame-retardants and smoke suppressants for flexible poly(vinyl chloride) (PVC) was evaluated using limiting oxygen index (LOI), smoke density rating (SDR) tests, scanning electron microscopy (SEM) and thermogravimetry analysis (TGA). The activation energy (Ea) of the original and flame retardant PVCs’ degradation processes was calculated by the Vyazovkin method. The results showed that the AZC can be used as a synergistic agent for MgCO3 as flame retardants agent of flexible PVC. The composites of MgCO3 and AZC cannot only decrease the initial decomposition temperature and increase the weight loss rate in the first stage, but also can promote the char formation in the second stage. The AZC decreased the Ea of the degradation reaction of PVC in the first stage and MgCO3 increased the Ea in the second stage, which means that the AZC combined with MgCO3, catalyzed the dehydrochlorination, promoted the early crosslinking for the PVC compound and improve the stability of the char residue. The SEM results also show that the char residue of MgCO3/AZC treated sample has a continuous and denser structure, which can be used as a barrier for the PVC bulk.

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The Flammability of Polyacrylonitrile and Its Copolymers I. The Flammability Assessment Using Pressed Powdered Polymer Samples

Journal of Fire Sciences ◽

10.1177/073490419301100505 ◽

1993 ◽

Vol 11 (5) ◽

pp. 442-456 ◽

Cited By ~ 14

Author(s):

Jun Zhang ◽

Michael E. Hall ◽

A. Richard Horrocks

Keyword(s):

Flame Retardant ◽

Flame Retardancy ◽

Flame Retardants ◽

Oxygen Index ◽

Char Residue ◽

Acrylic Polymer ◽

Limiting Oxygen Index ◽

Convenient Means ◽

Burning Rates ◽

Polymer Flammability

This paper is the first in a series of four which investigates the burning behaviour and the influence of flame retardant species on the flam mability of fibre-forming polymer and copolymers of acrylonitrile. A pressed powdered polymer sheet technique is described that enables a range of polymer compositions in the presence and absence of flame retardants to be assessed for limiting oxygen index, burning rate and char residue deter minations. The method offers a rapid, reproducible and convenient means of screening possible flame retardant systems, and LOI values compare favourably with those of films and fabrics comprising the same polymeric type. Burning rates, however, are sensitive to changes in physical sample character such as form (film vs. powder sheet) and density. Thus the technique forms an excellent basis for the generation of burning data which will enable comprehensive studies of acrylic polymer flammability and flame retardancy to be undertaken.

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Highly Efficient Composite Flame Retardants for Improving the Flame Retardancy, Thermal Stability, Smoke Suppression, and Mechanical Properties of EVA

Materials ◽

10.3390/ma13051251 ◽

2020 ◽

Vol 13 (5) ◽

pp. 1251

Author(s):

Yilin Liu ◽

Bin Li ◽

Miaojun Xu ◽

Lili Wang

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Heat Release ◽

Flame Retardant ◽

Production Rate ◽

Flame Retardancy ◽

Flame Retardants ◽

Mass Loss Rate ◽

Smoke Suppression ◽

Average Mass

Ethylene vinyl acetate (EVA) copolymer has been used extensively in many fields. However, EVA is flammable and releases CO gas during burning. In this work, a composite flame retardant with ammonium polyphosphate (APP), a charring–foaming agent (CFA), and a layered double hydroxide (LDH) containing rare-earth elements (REEs) was obtained and used to improve the flame retardancy, thermal stability, and smoke suppression for an EVA matrix. The thermal analysis showed that the maximum thermal degradation temperature of all composites increased by more than 37 °C compared with that of pure EVA. S-LaMgAl/APP/CFA/EVA, S-CeMgAl/APP/CFA/EVA, and S-NdMgAl/APP/CFA/EVA could achieve self-extinguishing behavior according to the UL-94 tests (V-0 rating). The peak heat release rate (pk-HRR) indicated that all LDHs containing REEs obviously reduced the fire strength in comparison with S-MgAl. In particular, pk-HRR of S-LaMgAl/APP/CFA/EVA, S-CeMgAl/APP/CFA/EVA and S-NdMgAl/APP/CFA/EVA were all decreased by more than 82% in comparison with pure EVA. Furthermore, the total heat release (THR), smoke production rate (SPR), and production rate of CO (COP) also decreased significantly. The average mass loss rate (AMLR) confirmed that the flame retardant exerted an effect in the condensed phase of the composites. Meanwhile, the combination of APP, CFA, and LDH containing REEs allowed the EVA matrix to maintain good mechanical properties.

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Novel Intumescent Flame Retardant Masterbatch Prepared Through Different Processes and Its Application in EPDM/PP Thermoplastic Elastomer: Thermal Stability, Flame Retardancy, and Mechanical Properties

Polymers ◽

10.3390/polym11010050 ◽

2018 ◽

Vol 11 (1) ◽

pp. 50 ◽

Cited By ~ 10

Author(s):

Weidi He ◽

Ying Zhou ◽

Xiaolang Chen ◽

Jianbing Guo ◽

Dengfeng Zhou ◽

...

Keyword(s):

Mechanical Properties ◽

Thermal Stability ◽

Flame Retardancy ◽

Flame Retardants ◽

Thermoplastic Elastomer ◽

Molar Ratio ◽

Limiting Oxygen Index ◽

Cone Calorimeter Test ◽

Properties Of Materials ◽

Intumescent Flame Retardants

In this work, the ethylene-propylene-diene monomer/polypropylene (EPDM/PP) thermoplastic elastomer filled with intumescent flame retardants (IFR) is fabricated by melting blend. The IFR are constituted with melamine phosphate-pentaerythritol (MP/PER) by compounding and reactive extruding, respectively. The effects of two kinds of MP/PER with different contents on the thermal stability, flame retardancy, and mechanical properties of materials are investigated by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA), limiting oxygen index (LOI), UL-94, cone calorimeter test (CCT), and scanning electron microscopy (SEM). FTIR results show that the reactive extruded MP/PER partly generates melamine pyrophosphate (MPP) compared with compound masterbatches. TGA data indicate that the best thermal stability is achieved when the molar ratio of MP/PER reaches 1.8. All the reactive samples show a higher flame retardancy than compound ones. The CCT results also exhibit the same trend as above in heat release and smoke production rate. The EPDM/PP composites filled with 30 and 35% reactive MP/PER exhibit the improved flame retardancy but become stiffer and more brittle. SEM photos display that better dispersion and smaller particle size are obtained for reactive samples.

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Solid Wastes Toward Flame Retardants for Polymeric Materials: A Review

Frontiers in Materials ◽

10.3389/fmats.2021.712188 ◽

2021 ◽

Vol 8 ◽

Author(s):

Chuanhua Gao ◽

Siqi Huo ◽

Zhenhu Cao

Keyword(s):

Thermal Stability ◽

Flame Retardant ◽

Flame Retardancy ◽

Mass Production ◽

Flame Retardants ◽

Polymeric Materials ◽

Solid Wastes ◽

Smoke Suppression ◽

Future Perspectives ◽

Recycle And Reuse

It has been significant yet challenging to recycle and reuse different kinds of wastes because of their mass production within society. Many efforts have been conducted to reuse wastes in different fields. Interestingly, some wastes have been employed to replace traditional petroleum-based flame retardants for polymeric materials. This review focuses on the recent development of waste flame retardants and their impacts on thermal stability, flame retardancy, and smoke suppression of polymers, followed by representative flame-retardant mechanisms. Finally, the key challenges associated with waste flame retardants are presented, and some future perspectives are proposed.

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Flame-retardancy and smoke suppression characteristics of bamboo impregnated with silicate-intercalated calcium aluminum hydrotalcates

BioResources ◽

10.15376/biores.16.1.1311-1324 ◽

2020 ◽

Vol 16 (1) ◽

pp. 1311-1324

Author(s):

Yating Hua ◽

Chungui Du ◽

Huilong Yu ◽

Ailian Hu ◽

Rui Peng ◽

...

Keyword(s):

Heat Release ◽

Flame Retardant ◽

Flame Retardancy ◽

Flame Retardants ◽

Mass Loss Rate ◽

Fire Retardant ◽

Smoke Suppression ◽

Cone Calorimetry ◽

Before And After ◽

Carbon Monoxide Yield

Flame-retardant silicate-intercalated calcium aluminum hydrotalcites (CaAl-SiO3-LDHs) were synthesized to treat bamboo for retardancy, to overcome the bamboo’s flammability and reduce the production of toxic smoke during combustion. The microstructure, elemental composition, flame retardancy, and smoke suppression characteristics of the bamboo before and after the fire-retardant treatment with different pressure impregnation were studied using a scanning electron microscope (SEM), elemental analysis (EDX), and cone calorimetry. It was found that CaAl-SiO3-LDHs flame retardants can effectively fill and cover the cell wall surface and the cell cavity of bamboo without damaging the microstructure. As compared to the non-flame-retardant bamboo, the heat release rate (HRR) of the CaAl-SiO3-LDHs flame-retardant bamboo was significantly reduced, the total heat release (THR) decreased by 31.3%, the residue mass increased by 51.4%, the time to ignition (TTI) delay rate reached 77.8%, the mass loss rate (MLR) decreased, and the carbon formation improved. Additionally, as compared to the non-flame-retardant bamboo, the total smoke release (TSR) of the CaAl-SiO3-LDHs flame-retardant bamboo decreased by 38.9%, and the carbon monoxide yield (YCO) approached zero. Thus, the CaAl-SiO3-LDHs flame-retardant bamboo has excellent flame-retardancy and smoke suppression characteristics.

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Effect of β-Cyclodextrin and Ammonium Polyphosphate on Flame Retardancy of Jute/Polypropylene Composites

Materials Science Forum ◽

10.4028/www.scientific.net/msf.1001.219 ◽

2020 ◽

Vol 1001 ◽

pp. 219-223

Author(s):

Min Gao

Keyword(s):

Flame Retardancy ◽

Flame Retardants ◽

Film Formation ◽

Polypropylene Fiber ◽

Ammonium Phosphate ◽

Total Content ◽

Thermal Compression ◽

Limiting Oxygen Index ◽

Polypropylene Composites ◽

Thermal Stability Of

The jute and polypropylene fiber (PP) were formed into jute/PP composite by carding, netting and needling. Using surface dusting process, β-CD and ammonium phosphate (APP) were combined and hot pressed to form a flame-retardant layer on the surface of jute/PP composite. The results show that the thermal compression film formation on the surface of jute/PP composite after β-CD and APP compounding can significantly improve the flame retardancy and thermal stability of the jute/PP composite. When the mass ratio of β-CD to APP is 1:2 and keeping the 20wt% total content of the flame retardants, the jute/PP composite becomes extinguished after 58s combustion. The limiting oxygen index (LOI) value is 26.6%, which reaches the third fire resistance according to Japan's JISD 1201-77 standard. The heat release rate and effective combustion calorific show the lowest value and the carbon residual at 700°C is increased by 11. 68%.

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