Synthesis and characterization of flame-retardant-wrapped carbon nanotubes and its flame retardancy in epoxy nanocomposites

2021 ◽  
pp. 096739112110245
Author(s):  
Jiangbo Wang
Keyword(s):  
Carbon Nanotubes ◽  
Heat Release ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Total Heat Release ◽  
Pristine Cnts ◽  
Peak Heat Release Rate ◽  
Ep Matrix ◽  
Better Than

A novel phosphorus-silicon containing flame-retardant DOPO-V-PA was used to wrap carbon nanotubes (CNTs). The results of FTIR, XPS, TEM and TGA measurements exhibited that DOPO-V-PA has been successfully grafted onto the surfaces of CNTs, and the CNTs-DOPO-V-PA was obtained. The CNTs-DOPO-V-PA was subsequently incorporated into epoxy resin (EP) for improving the flame retardancy and dispersion. Compared with pure EP, the addition of 2 wt% CNTs-DOPO-V-PA into the EP matrix could achieve better flame retardancy of EP nanocomposites, such as a 30.5% reduction in peak heat release rate (PHRR) and 8.1% reduction in total heat release (THR). Furthermore, DMTA results clearly indicated that the dispersion for CNTs-DOPO-V-PA in EP matrix was better than pristine CNTs.

Epoxy resin/cyanate ester composites containing DOPO and wollastonite with simultaneously improved flame retardancy and thermal resistance

2020 ◽  
Vol 32 (6) ◽  
pp. 710-718
Author(s):  
Zhengzhou Wang ◽  
Xin Gao ◽  
Wenfeng Li
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Oxygen Index ◽  
Thermal Studies ◽  
Cyanate Ester ◽  
Total Heat Release ◽  
Limiting Oxygen Index ◽  
Peak Heat Release Rate ◽  
Ul 94

Flame-retardant epoxy (EP) resin/cyanate ester (CE) composites were prepared with 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) and wollastonite (Wo). The combustion behavior of the flame-retardant EP/CE composites was investigated by limiting oxygen index (LOI), UL-94, and cone calorimeter tests. It is found that the EP/CE composite containing 7 wt% DOPO and 3 wt% Wo (sample 7DO/3Wo/EP/CE) exerts the best flame retardancy (LOI 35.5% and UL-94 V-0 rating). The peak heat release rate and total heat release of sample 7DO/3Wo/EP/CE increase slightly, while total smoke release decreases about 14% compared with the EP/CE composite containing 10 wt% DOPO (sample 10DO/EP/CE). Thermal studies indicate that the glass transition temperature and temperature at 5% mass loss of sample 7DO/3Wo/EP/CE are higher than that of sample 10DO/EP/CE. Moreover, the mechanical properties of EP/CE composites were investigated.

scholarly journals A Novel Self-Assembled Graphene-Based Flame Retardant: Synthesis and Flame Retardant Performance in PLA

Polymers ◽  
2021 ◽  
Vol 13 (23) ◽  
pp. 4216
Author(s):  
Peixin Yang ◽  
Hanguang Wu ◽  
Feifei Yang ◽  
Jie Yang ◽  
Rui Wang ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Total Heat Release ◽  
Flame Resistance ◽  
Nucleation Agent ◽  
Char Layer ◽  
Self Assembling ◽  
Peak Heat Release Rate ◽  
Positive Effect

In this study, a novel flame retardant (PMrG) was developed by self-assembling melamine and phytic acid (PA) onto rGO, and then applying it to the improvement of the flame resistance of PLA. PMrG simultaneously decreases the peak heat release rate (pHRR) and the total heat release (THR) of the composite during combustion, and enhances the LOI value and the time to ignition (TTI), thus significantly improving the flame retardancy of the composite. The flame retardant mechanism of the PMrG is also investigated. On one hand, the dehydration of PA and the decomposition of melamine in PMrG generate non-flammable volatiles, such as H2O and NH3, which dilute the oxygen concentration around the combustion front of the composite. On the other hand, the rGO, melamine, and PA components in PMrG create a synergistic effect in promoting the formation of a compact char layer during the combustion, which plays a barrier role and effectively suppresses the release of heat and smoke. In addition, the PMrGs in PLA exert a positive effect on the crystallization of the PLA matrix, thus playing the role of nucleation agent.

scholarly journals Preparation and Characterization of DOPO-Functionalized MWCNT and Its High Flame-Retardant Performance in Epoxy Nanocomposites

Polymers ◽  
2020 ◽  
Vol 12 (3) ◽  
pp. 613 ◽  
Author(s):  
Liqiang Gu ◽  
Chen Qiu ◽  
Jianhui Qiu ◽  
Youwei Yao ◽  
Eiichi Sakai ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Epoxy Resin ◽  
Epoxy Resins ◽  
Phosphorus Content ◽  
Co2 Production ◽  
Peak Heat Release Rate ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

In this work, functionalized multi-walled carbon nanotubes (MWCNT) were synthesized by the reaction between acylated MWCNT and 10-(2,5-dihydroxyphenyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (ODOPB). The obtained MWCNT-ODOPB was well dispersed into epoxy resins together with aluminum diethylphosphinate (AlPi) to form flame-retardant nanocomposites. The epoxy resin nanocomposite with phosphorus content of 1.00 wt % met UL 94 V-0 rating, exhibited LOI value of 39.5, and had a higher Tg compared to neat epoxy resin, which indicates its excellent flame retardant performance. These experimental results indicated that MWCNT-ODOPB was a compatible and efficient flame retardant for epoxy resins. Moreover, cone calorimeter analysis showed that the peak heat release rate (pHRR), total heat release (THR) values, and CO2 production profiles of the composites decreased with an increase in the additional amount of phosphorus.

scholarly journals Synthesis of a phosphoramidate flame retardant and its flame retardancy on cotton fabrics

e-Polymers ◽  
2020 ◽  
Vol 20 (1) ◽  
pp. 550-560
Author(s):  
Huaifang Wang ◽  
Yingli Cai ◽  
Zhiming Jiang ◽  
Shengnan Guo ◽  
Ping Zhu
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Cotton Fabrics ◽  
Limiting Oxygen Index ◽  
Flammability Test ◽  
Peak Heat Release Rate ◽  
Structure Surface ◽  
Ft Ir ◽  
Butanetetracarboxylic Acid

AbstractA phosphoramidate flame retardant (dimethyl N,N-bis(2-hydroxyletheyl)phosphoramidate, DMBHP) was synthesized and applied to cotton fabrics for enhancing the flame retardancy. The structure of DMBHP was characterized by FT-IR and NMR. The flame retardancy and combustion behavior of the treated cotton fabrics were evaluated using the vertical flammability test (VFT), limiting oxygen index (LOI), and the cone calorimetric test. Moreover, to further analyze the flame retardant action of DMBHP in cotton fabrics, thermal degradability of the treated fabrics, as well as the chemical structure, surface morphology, and element contents of the char residue of the DMBHP-treated fabrics were also evaluated. The results show that, after treating with DMBHP, the cotton fabrics acquired a LOI value from 18.1 to 31.1 with the concentration increasing to 30% and self-extinguished in VFT tests when treated with up to 15% DMBHP. Besides, the total heat release and the peak heat release rate of DMBHP (30%)-treated fabric decreased obviously compared with the pure cotton along with more residue retained. TG, SEM, and EDS results of treated cotton fabric and the corresponding residue after burning showed that DMBHP has the capability of enhancing char formation. In addition, DMBHP will confer cotton fabrics a certain durability against washing with the help of 1,2,3,4-butanetetracarboxylic acid (BTCA) and citric acid (CA).

Research on the Mechanism of a Novel Si/P Flame Retardant

2012 ◽  
Vol 441 ◽  
pp. 436-441 ◽  
Author(s):  
Ran Wang ◽  
Xiao Chun Wang
Keyword(s):  
Fourier Transform ◽  
Phosphoric Acid ◽  
Heat Release ◽  
Flame Retardant ◽  
Low Temperatures ◽  
Tetraethyl Orthosilicate ◽  
Total Heat Release ◽  
Cone Calorimetry ◽  
X Ray ◽  
Peak Heat Release Rate

A novel Si/P flame retardant was prepared using tetraethyl orthosilicate (TEOS) and phosphoric acid (H3PO4). Cotton fabric treated with the flame retardant was characterized by cone calorimetry, thermogravimetric analysis (TGA), X-ray fluorescence spectroscopy, and Fourier transform infrared spectroscopy. The peak heat release rate (pHRR) and total heat release (THR) of the fabric treated with TEOS/H3PO4 are lower than those of the fabric treated with TEOS or H3PO4 alone. The HRR and THR of the treated fabric decrease from 145.66 kW/m2 and 1.68 MJ/m2 to 70.76 kW/m2 and 0.67 MJ/m2, respectively. Total smoke production decreases from 0.080 to 0.014 m2/m2. TGA revealed that cellulose dehydration increases at low temperatures because of the addition of phosphoric acid and the production of charcoal. The generated charcoal is dense. The P and Si contents markedly increase, and exist in the charcoal in the form of P-O-C and Si-O bonds, respectively. On the basis of these results, we conclude that the main mechanism of TEOS/H3PO4 is that of a condensed-phase flame retardant. Good flame retardant synergism occurs between TEOS and H3PO4.

scholarly journals Functionalization of Graphene Oxide with Polysilicone: Synthesis, Characterization, and Its Flame Retardancy in Epoxy Resin

Polymers ◽  
2021 ◽  
Vol 13 (21) ◽  
pp. 3857
Author(s):  
Jiangbo Wang
Keyword(s):  
Graphene Oxide ◽  
Heat Release ◽  
Epoxy Resin ◽  
Flame Retardancy ◽  
Mechanical Analysis ◽  
Silica Layer ◽  
Atomic Force ◽  
Peak Heat Release Rate ◽  
Ep Matrix ◽  
The Fourier Transform

A novel polysilicone flame retardant (PMDA) has been synthesized and covalently grafted onto the surfaces of graphene oxide (GO) to obtain GO-PMDA. The chemical structure and morphology of GO-PMDA was characterized and confirmed by the Fourier transform infrared (FTIR) spectroscopy, X-ray photoelectron spectrometer (XPS), atomic force microscope (AFM), and thermogravimetric analysis (TGA). The results of dynamic mechanical analysis (DMA) indicated that the grafting of PMDA improved the dispersion and solubility of GO sheets in the epoxy resin (EP) matrix. The TGA and cone calorimeter measurements showed that compared with the GO, GO-PMDA could significantly improve the thermal stability and flame retardancy of EP. In comparison to pure EP, the peak heat release rate (pHRR) and total heat release (THR) of EP/GO-PMDA were reduced by 30.5% and 10.0% respectively. This greatly enhanced the flame retardancy of EP which was mainly attributed to the synergistic effect of GO-PMDA. Polysilicone can create a stable silica layer on the char surface of EP, which reinforces the barrier effect of graphene.

scholarly journals Synthesis and Characterization of Aluminum 2-Carboxyethyl-Phenyl-Phosphinate and Its Flame-Retardant Application in Polyester

Polymers ◽  
2019 ◽  
Vol 11 (12) ◽  
pp. 1969 ◽  
Author(s):  
Zhongying Yao ◽  
Xinxin Liu ◽  
Lijun Qian ◽  
Yajun Chen ◽  
Bo Xu ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Gas Phase ◽  
Oxygen Index ◽  
Peak Heat Release Rate ◽  
Flame Inhibition ◽  
Polyester Textile ◽  
Effective Heat Of Combustion ◽  
Limited Oxygen

A flame retardant aluminum 2-carboxyethyl-phenyl-phosphinate (CPA-Al) was synthesized through the salification reaction. The molecular structure of CPA-Al and thermal stability were characterized by solid nuclear magnetic resonance, Fourier transform infrared spectroscopy, and thermogravimetric analysis. Subsequently, CPA-Al mixed in polyurethane was coated on polyester textile to obtain flame-retardant samples. The addition of 14.7 wt.% CPA-Al in textile sample can bring a limited oxygen index (LOI) value of 24.5%, 0 s after flame time, and the vertical burning B1 rating. Meanwhile, the incorporated CPA-Al reduced the peak heat release rate, total heat release, average effective heat of combustion, and increased the charring capacity of polyester textiles in contrast to the samples without CPA-Al. CPA-Al exerted not only its flame inhibition effect in gas phase, but also the charring and barrier effect in the condensed phase. Besides, with an increasing CPA-Al ratio in polyester textile, the contact angle gradually decreased from 123.6° to 75.6°, indicating that the surficial property of coating from hydrophobic to hydrophilic, thereby increasing the moisture permeability of polyester textile.

Intumescent flame retardant coating for polyamide 6,6 (PA 6,6) fabrics containing carbon nanotubes: Synergistic effect of filler on thermal stability and flame retardancy

2018 ◽  
Vol 89 (10) ◽  
pp. 2031-2040 ◽  
Author(s):  
Fanglong Zhu ◽  
QQ Feng ◽  
YF Xu ◽  
JF Hu
Keyword(s):  
Carbon Nanotubes ◽  
Thermal Stability ◽  
Heat Release ◽  
Flame Retardant ◽  
Heat Release Rate ◽  
Flame Retardancy ◽  
Release Rate ◽  
Intumescent Flame Retardant ◽  
Flame Resistance ◽  
Limiting Oxygen Index

Flame retardant mixtures of multi-walled carbon nanotubes (MWCNTs) and intumescent flame retardant (IFR) coatings were applied to polyamide 6,6 (PA 6,6) fabrics to explore whether MWCNTs acted as a good synergist on the thermal stability and flame resistance of the IFR system. The influence of MWCNTs on the flame retardant properties and thermal degradation of the PA 6,6 fabrics were investigated by limiting oxygen index (LOI), vertical burning test (VBT), thermogravimetric analyzer (TGA), scanning electron microscopy (SEM) and cone calorimeter test (CCT). The peak heat release rate and total heat release of the IFR-PA 6,6 fabric with three kinds of wt% MWCNTs were lower than those of the only traditional IFR-PA 6,6 fabric (reduced by 74.2–76.4% and 74.3–76.5%, respectively). As compared to the traditional IFR coating, it was found that no enhancements for thermal stability and flame retardancy in terms of the ability to retard ignition were achieved for the MWCNT/IFR coating. These results demonstrated that the introduction of MWCNTs into an IFR coating can improve the flame retardancy of PA 6,6 fabric in terms of the heat release rate from CCT analysis, but it failed other burning measurements, such as LOI and VBT.

scholarly journals Improvement of Flame Retardancy of Polyurethane Foam Using DOPO-Immobilized Silica Aerogel

2021 ◽  
Vol 8 ◽  
Author(s):  
Xin’guo Zheng ◽  
Quanxiao Dong ◽  
Xi Wang ◽  
Peiyun Yu ◽  
Weimin Wang ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Flame Retardancy ◽  
Release Rate ◽  
Silica Aerogel ◽  
Cone Calorimeter ◽  
Polyurethane Foams ◽  
Total Heat Release ◽  
Microscale Combustion Calorimeter ◽  
Combustion Calorimeter

In this work, silica aerogel was modified by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-1-oxide (DOPO). Then DOPO-immobilized silica aerogel nanoparticles were used as a flame retardant to prepare flame-retardant polyurethane foams. Microscale combustion calorimeter and cone calorimeter tests were employed to evaluate the flame retardancy of polyurethane foams. It was found that both the heat release rate and the total heat release of the composites were reduced with the incorporation of DOPO immobilized silica aerogel. It is speculated that the DOPO-immobilized silica aerogel nanoparticles can inhibit the degradation of polyurethane and catalyze the formation of carbonaceous carbon on the surface.

scholarly journals Dual UV-Thermal Curing of Biobased Resorcinol Epoxy Resin-Diatomite Composites with Improved Acoustic Performance and Attractive Flame Retardancy Behavior

2021 ◽  
Vol 2 (1) ◽  
pp. 24-48
Author(s):  
Quoc-Bao Nguyen ◽  
Henri Vahabi ◽  
Agustín Rios de Anda ◽  
Davy-Louis Versace ◽  
Valérie Langlois ◽  
...  
Keyword(s):  
Heat Release ◽  
Flame Retardant ◽  
Epoxy Resin ◽  
Flame Retardancy ◽  
Sound Absorption ◽  
Flexural Modulus ◽  
Construction Materials ◽  
Acoustic Properties ◽  
Low Frequencies ◽  
Compacting Pressure

This study has developed novel fully bio-based resorcinol epoxy resin–diatomite composites by a green two-stage process based on the living character of the cationic polymerization. This process comprises the photoinitiation and subsequently the thermal dark curing, enabling the obtaining of thick and non-transparent epoxy-diatomite composites without any solvent and amine-based hardeners. The effects of the diatomite content and the compacting pressure on microstructural, thermal, mechanical, acoustic properties, as well as the flame behavior of such composites have been thoroughly investigated. Towards the development of sound absorbing and flame-retardant construction materials, a compromise among mechanical, acoustic and flame-retardant properties was considered. Consequently, the composite obtained with 50 wt.% diatomite and 3.9 MPa compacting pressure is considered the optimal composite in the present work. Such composite exhibits the enhanced flexural modulus of 2.9 MPa, a satisfying sound absorption performance at low frequencies with Modified Sound Absorption Average (MSAA) of 0.08 (for a sample thickness of only 5 mm), and an outstanding flame retardancy behavior with the peak of heat release rate (pHRR) of 109 W/g and the total heat release of 5 kJ/g in the pyrolysis combustion flow calorimeter (PCFC) analysis.

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