Effect of a Reactive-Type Flame Retardant on Thermal Stability of Thiol-ene Composites

Abstract The cellulose and starch present in the avocado seed can be chemically modified to obtain biofillers with fire retarding characteristics. The resulting composites could be used as substitute of the corresponding halogenated composites. For this, the avocado seed was first washed, dehydrated and pulverized, and thereafter, chemically modified with phosphoric acid in the presence of urea. This was studied using infrared spectroscopy, nuclear magnetic resonance and X-Ray photoelectron spectroscopy, in order to determine the resulting chemical structure and confirm the presence of the proposed functional groups. In addition, scanning electron microscopy and elemental analysis were used, respectively, to establish the resulting morphological changes, as well as the elements present on the surface of the modified material. Thermogravimetric analysis was also carried out in order to establish the thermal stability of the material and predict the effect on the flame retardancy due to the mentioned chemical modification. Further tests established that the obtained modified structure and morphology of the avocado seed was highly dependent on the method used to dehydrate the pulverized avocado seed. It was also determined that chemical modification greatly increased the thermal stability of the avocado seed in air atmosphere. The flame-retardant effect of the modified avocado seed was assessed in polyethylene/ethylene-vinyl-acetate (PE/EVA) composites via cone calorimeter tests. These results showed that the modified avocado seed decreased the peak of the heat release rate (pHRR) by 50% and the total heat released (THR) by 15%. This phosphated avocado seed could be a good option as a renewable biofiller for polymer composites with enhanced flame-retardant properties.

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Flame-retardant behaviors of aluminum phosphates coated sepiolite in epoxy resin

Journal of Fire Sciences ◽

10.1177/0734904120934085 ◽

2020 ◽

pp. 073490412093408

Author(s):

Wei Yan ◽

Pu Xie ◽

Zhengwei Yang ◽

Guangjin Luo ◽

Weijiang Huang ◽

...

Keyword(s):

Thermal Stability ◽

Flame Retardant ◽

Epoxy Resin ◽

Mechanical Performance ◽

Oxygen Index ◽

One Pot ◽

Heterogeneous Precipitation ◽

Aluminum Phosphates ◽

Thermal Stability Of ◽

Limited Oxygen

Aluminum phosphates coated sepiolite nanocomposite was fabricated via a simple one-pot heterogeneous precipitation strategy, and the effects of aluminum phosphates on the morphology of aluminum phosphates coated sepiolite were investigated. Moreover, the effect of aluminum phosphates coated sepiolite on the flame-retardant behavior, mechanical properties, and thermal stability of epoxy resin have been discussed. The results indicated that the introduction of only 20 wt% aluminum phosphates coated sepiolite in epoxy resin increased the limited oxygen index from 21.8% to 30.1%, thus the material met the UL-94 V-0 rating. Thermogravimetric analyses revealed that char yield increased in the presence of aluminum phosphates coated sepiolite form thermally stable carbonaceous char. Aluminum phosphates–coated sepiolite could improve the mechanical performance, thermal stability of epoxy resin.

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Investigation of the Structure-Property Effect of Phosphorus-Containing Polysulfone on Decomposition and Flame Retardant Epoxy Resin Composites

Polymers ◽

10.3390/polym11020380 ◽

2019 ◽

Vol 11 (2) ◽

pp. 380 ◽

Cited By ~ 5

Author(s):

Wei Zhao ◽

Yongxiang Li ◽

Qiushi Li ◽

Yiliang Wang ◽

Gong Wang

Keyword(s):

Thermal Stability ◽

Flame Retardant ◽

Flame Retardancy ◽

Phosphorus Content ◽

Structure Property ◽

Scanning Calorimetry ◽

Inhibition Effect ◽

Phosphorus Containing ◽

High Degree ◽

Thermal Stability Of

The flame retardant modification of epoxy (EP) is of great signification for aerospace, automotive, marine, and energy industries. In this study, a series of EP composites containing different variations of phosphorus-containing polysulfone (with a phosphorus content of approximately 1.25 wt %) were obtained. The obtained EP/polysulfone composites had a high glass transition temperature (Tg) and high flame retardancy. The influence of phosphorus-containing compounds (ArPN2, ArPO2, ArOPN2 and ArOPO2) on the thermal properties and flame retardancy of EP/polysulfone composites was investigated by thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), a UL-94 vertical burning test, and cone calorimeter tests. The phosphorus-containing polysulfone enhanced the thermal stability of EP. The more stable porous char layer, less flammable gases, and a lower apparent activation energy at a high degree of conversion demonstrated the high gas inhibition effect of phosphorus-containing compounds. Moreover, the gas inhibition effect of polysulfone with a P–C bond was more efficient than the polysulfone with a P–O–C bond. The potential for optimizing flame retardancy while maintaining a high Tg is highlighted in this study. The flame-retardant EP/polysulfone composites with high thermal stability broaden the application field of epoxy.

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Synthesis of a Novel Phosphorous-Nitrogen Based Charring Agent and Its Application in Flame-retardant HDPE/IFR Composites

Polymers ◽

10.3390/polym11061062 ◽

2019 ◽

Vol 11 (6) ◽

pp. 1062 ◽

Cited By ~ 13

Author(s):

Junlei Chen ◽

Jihui Wang ◽

Aiqing Ni ◽

Hongda Chen ◽

Penglong Shen

Keyword(s):

Thermal Stability ◽

Heat Release ◽

Flame Retardant ◽

Flame Retardancy ◽

Fire Hazard ◽

Weight Ratio ◽

Charring Agent ◽

Migration Percentage ◽

Ul 94 ◽

Thermal Stability Of

In this work, a novel phosphorous–nitrogen based charring agent named poly(1,3-diaminopropane-1,3,5-triazine-o-bicyclic pentaerythritol phosphate) (PDTBP) was synthesized and used to improve the flame retardancy of high-density polyethylene (HDPE) together with ammonium polyphosphate (APP). The results of Fourier transform infrared spectroscopy (FTIR) and 13C solid-state nuclear magnetic resonance (NMR) showed that PDTBP was successfully synthesized. Compared with the traditional intumescent flame retardant (IFR) system contained APP and pentaerythritol (PER), the novel IFR system (APP/PDTBP, weight ratio of 2:1) could significantly promote the flame retardancy, water resistance, and thermal stability of HDPE. The HDPE/APP/PDTBP composites (PE3) could achieve a UL-94 V-0 rating with LOI value of 30.8%, and had a lower migration percentage (2.2%). However, the HDPE/APP/PER composites (PE5) had the highest migration percentage (4.7%), lower LOI value of 23.9%, and could only achieve a UL-94 V-1 rating. Besides, the peak of heat release rate (PHRR), total heat release (THR), and fire hazard value of PE3 were markedly decreased compared to PE5. PE3 had higher tensile strength and flexural strength of 16.27 ± 0.42 MPa and 32.03 ± 0.59 MPa, respectively. Furthermore, the possible flame-retardant mechanism of the APP/PDTBP IFR system indicated that compact and continuous intumescent char layer would be formed during burning, thus inhibiting the degradation of substrate material and improving the thermal stability of HDPE.

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Synthesis and Application of a Novel Intumescent Flame Retardant Containing Ferrocenyl

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1033-1034.931 ◽

2014 ◽

Vol 1033-1034 ◽

pp. 931-936

Author(s):

Cong Yan Chen ◽

Rui Lan Fan ◽

Guan Qun Yun

Keyword(s):

Thermal Stability ◽

Flame Retardant ◽

Flame Retardants ◽

Intumescent Flame Retardant ◽

Limiting Oxygen Index ◽

Good Thermal Stability ◽

H Nmr ◽

Positive Effect ◽

Thermal Stability Of ◽

Phosphate Groups

A novel intumescent flame retardant (IFR) containing ferrocene and caged bicyclic phosphate groups, 1-oxo-4-[4'-(ferrocene carboxylic acid phenyl ester)] amide-2, 6, 7-trioxa-1-phosphabicyclo- [2.2.2] octane (PFAM), was successfully synthesized. The synthesized PFAM were added to flammable polyurethane (PU) as flame retardants and smoke suppressants. The structure of PFAM was characterized by Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (1H NMR) and elemental analysis. Thermal stability of PFAM was tested by themogravimetric analysis (TGA). The results revealed that PFAM had good thermal stability and high char weight, the char weight up to 54% at 600 °C. Flammability properties of PU/PFAM composites were investigated by limiting oxygen index (LOI) test and UL-94 test, respectively. The results of LOI tests showed that the addition of PFAM enhanced flame retardancy of PU. When the content of PFAM reaches to 3%, the LOI value is 22.2. The morphologies of the char for PU and PU/3% PFAM composite can be obtained after LOI testing were examined by SEM. The results demonstrated that PFAM could promote to form the compact and dense intumescent char layer. Experiments showed that, the PFAM application of polyurethane showed positive effect.

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Effect of Fumed Silica and Zinc Borate on the Thermogravimetric Analysis Curves of ABS/Magnesium Hydroxide Composite

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.599-601.183 ◽

2014 ◽

Vol 599-601 ◽

pp. 183-186

Author(s):

Zhang Ting Li ◽

Yue Qun Lu ◽

Li Li Fan ◽

Pei Bang Dai ◽

Xia Su ◽

...

Keyword(s):

Mechanical Property ◽

Thermal Stability ◽

Flame Retardant ◽

Fumed Silica ◽

Acrylonitrile Butadiene Styrene ◽

Zinc Borate ◽

Processing Temperature ◽

Great Decrease ◽

Thermal Stability Of ◽

Butadiene Styrene

For achieving sufficient flame retardancy, high magnesim hydroxide (MH) content is needed in MH flame retardant Acrylonitrile-butadiene-styrene copolymer (ABS) composites (ABS/MH), which will cause a great decrease in mechanical property and difficulty in preparing samples for measurement. We prepared ABS/MH filled high 60.0% flame retardant by compounding ABS and modified flame retardant MH, fumed silica (SiO2) and zinc borate (ZB) via TX-10 phosphate/polyacrylate latex and studied the effect of a small amount of SiO2 and ZB with MH in ABS for improving the thermal decomposition of ABS/MH. The thermal stability of the modified flame retardant could meet the processing temperature of ABS. The incorporation of ZB, SiO2 or SiO2/ZB could improve the thermal stability of ABS/MH.

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