Synergistic Effect of Hexaphenoxycyclotriphosphazene and Aluminium Tri-Hydroxide on Flame Retardancy and Smoke Suppression of Epoxy Resin

Flame retardancy and smoke suppression of polymer materials are key problems to be considered for applications that have a potential fire hazard. This study selected hexaphenoxycyclotriphosphazene (HPCTP) and aluminium tri-hydroxide (ATH) powder as an integrated flame retardant treatment in epoxy resin (EP) which is usually used as the matrix of a composite. The characteristics of flame retardancy and smoke suppression were investigated. The results showed that when treated with HPCTP and ATH, the resin exhibits superior properties, resisting flame development and smoke release. Based on analysis of the surface structure of the burned materials by scanning electron microscopy–energy dispersive spectroscopy and X-ray photoelectron spectroscopy, it was confirmed that HPCTP and ATH can attract a lot of heat to slow down decomposition of the resin and produce a comprehensive protection system consisting of a non-flammable gas and solid phases during burning. Non-flammable gas can reduce the concentration of flammable gas to inhibit combustion. In addition, H2O vapour can also reduce the concentration of flammable gas to inhibit combustion. Meanwhile, solid phase films can insulate air to slow down combustion and smoke release.

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On improving flame retardant and smoke suppression efficiency of epoxy resin doped with aluminum tri-hydroxide

Advanced Composites Letters ◽

10.1177/2633366x19894597 ◽

2019 ◽

Vol 28 ◽

pp. 2633366X1989459 ◽

Cited By ~ 1

Author(s):

Guoqiang Chai ◽

Guoqing Zhu ◽

Shuai Gao ◽

Jinju Zhou ◽

Yunji Gao ◽

...

Keyword(s):

Activation Energy ◽

Epoxy Resin ◽

Smoke Suppression ◽

Superior Performance ◽

Residual Carbon ◽

Second Stage ◽

Suppression Efficiency ◽

Peak Heat Release Rate ◽

Flammable Gas ◽

Flame Development

Aluminum tri-hydroxide (ATH) was selected as a retardant doped into epoxy resin (EP), and smoke suppression and flame retardancy of ATH/EP were investigated. The results showed that ATH-doped EP has superior performance resisting the flame development and smoke release to EP. Peak heat release rate of EP doped with 15-wt% ATH decreased by 28.49% in comparison with EP; total smoke release of it decreased by 17.65%; production rate of carbon monoxide decreased by 30.24%. The activation energy of it was much smaller than EP due to the decomposition of ATH, but it was 30–40 kJ mol−1 higher than EP in the second stage. Based on analysis of the residual carbon, it was confirmed that ATH can attract lots of heat to produce aluminum oxide (Al2O3) films and H2O at high temperature. H2O decreases the production of flammable gas to inhibit combustion, and Al2O3 films adhered to the residue carbon can insulate air to reduce combustion and smoke release.

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Investigation of nickel ammonia phosphate with different morphologies as a new high-efficiency flame retardant for epoxy resin

High Performance Polymers ◽

10.1177/0954008319867369 ◽

2019 ◽

Vol 32 (4) ◽

pp. 359-370 ◽

Cited By ~ 1

Author(s):

Weiwei Zhang ◽

Hongjuan Wu ◽

Weihua Meng ◽

Jiahe Li ◽

Yumeng Cui ◽

...

Keyword(s):

Flame Retardant ◽

Epoxy Resin ◽

Flame Retardancy ◽

Photoelectron Spectroscopy ◽

High Efficiency ◽

Ammonium Phosphate ◽

Cone Calorimetry ◽

Limiting Oxygen Index ◽

X Ray ◽

The Matrix

Nanowires, nanosheets, and microflowers of nickel ammonium phosphate (NiNH4PO4·H2O) were synthesized by a mixed solvothermal method and used to improve the flame retardancy of epoxy resin (EP). The solvent concentration and surfactant content were found to play a key role in nucleation and growth of NiNH4PO4·H2O. The structure of NiNH4PO4·H2O was characterized by X-ray diffraction and X-ray photoelectron spectroscopy. The flame retardancy, thermostability, mechanical properties, and flame retardancy mechanism of EP/NiNH4PO4·H2O composites were analyzed using the limiting oxygen index (LOI), cone calorimetry (Cone), mechanical property tests, thermogravimetric analysis, and thermogravimetric–Fourier transform infrared spectroscopy. The results indicated that NiNH4PO4·H2O has proper thermal stability and greatly improves the flame retardancy of EP. The nanosheets outperformed the other morphologies; the EP/5% NiNH4PO4·H2O nanosheets have an LOI of 35.2%, which exceeds that of pure EP (24.7%). Furthermore, Cone showed that these nanosheets have the lowest peak heat release rate and peak smoke production rate, which are 69.1% and 36.5% lower than those of pure EP, respectively. NiNH4PO4·H2O can promote the formation of a stable char layer and release nonflammable gases, thus protecting the matrix by preventing heat and oxygen transfer and reducing the concentration of combustible gas. NiNH4PO4·H2O is expected to serve as a new high-efficiency flame retardant for EP.

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