JOURNAL OF FIRE SCIENCES
·
2018
·
IF 1.296
Daikun Jia,Jiyu He,Rongjie Yang
DOPO and its derivatives are excellent phosphorus-based flame retardants, which are applied to a series of polymer materials. In this article, a DOPO derivative bearing an active terminal epoxy group was synthesized using a non-solvent method. Fourier transform infrared spectroscopy, nuclear magnetic resonance, mass spectrometry, ultra-performance liquid chromatography, differential scanning calorimetry, thermogravimetric analysis, and viscosity measurements were performed to determine its molecular structure, purity, thermal performance, and fluidity. A possible fragmentation mechanism of the as-prepared DOPO derivative was analyzed using electron ionization mass spectrometer. All the results indicate that the synthesis was successful and the product had satisfactory purity and its initial decomposition temperature (T5%) under nitrogen and air atmosphere was 246°C and 240°C, respectively. Then, as a comparison with dimethyl methyl phosphonate, triethyl phosphate, and DOPO, e-DOPO was applied to a rigid polyurethane foam to investigate its effect on the flame retardancy, thermal stability, and cell morphology of polyurethane foam by limiting oxygen index, cone calorimetry, thermogravimetric analysis, and scanning electron microscopy. The results indicate that e-DOPO has a greater effect than DOPO and can effectively reduce the heat release and smoke release and improve the limiting oxygen index and thermal performance of the polyurethane foam. The cell size of the sample containing e-DOPO was more uniform.
研究领域:
材料科学
·
聚合物化学
·
阻燃性
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 5
·51593
·
IF 3.125
Xinyu Wang,Chenyu Zhou,Shengsong Dai,Junjie Wang,Zhiquan Pan,Hong Zhou
A bio-based flame retardant (PDE) was synthesized through a facile one-pot reaction of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) with protocatechualdehyde and ethanol. PDE was fully characterized by fourier transform infrared spectroscopy (FTIR), 1 H NMR, 31 P NMR and ESI-MS. Epoxy resin (EP) with 9 wt% PDE (EP/9%PDE) passed UL94 V-0 rating and possessed the limited oxygen index (LOI) value of 33.2%, the curved EP thermosets kept transparent. When chitosan (CS) was used to replace one-third of PDE in EP/9% PDE, the modified EP also passed UL94 V-0 rating with the LOI value of 32.3%, the curved thermosets kept transparent and owned better absorption effect toward ultraviolet light. Cone calorimeter test and TG-FTIR analysis were performed on the EP samples, the chars after burning were characterized by scanning electron microscope (SEM), energy-dispersive X-Ray spectroscopy (EDX), Raman spectrum and FTIR. The results showed that the synergistic effect of PDE-CS on flame retardant was ascribed to the protective effect of denser char layer, the release of some phosphorus containing free radicals and the dilution effect of released nonflammable gases such as H 2 O and CO 2 .
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2015
·
IF 3.163
Weihua Xu,Alvianto Wirasaputra,Shumei Liu,Yanchao Yuan,Jianqing Zhao
A highly effective 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based flame retardant (D-bp) was successfully synthesized via the addition reaction between DOPO and Schiff-base obtained in advance by the condensation of 4,4’-diaminodiphenyl methane (DDM) and 4-hydroxybenzaldehyde. D-bp was used as co-curing agent to improve the flame retardancy of DDM/diglycidyl ether of bisphenol A (DGEBA) system. Non-isothermal curing kinetics, thermal and flame-retardant properties of cured epoxy resins were studied by differential scanning calorimeter (DSC), thermogravimeric analysis (TGA), UL94 vertical burning test, limited oxygen index (LOI) and cone calorimeter test. The morphology of residues after cone calorimeter test was observed by scanning electron microscope (SEM). The results revealed that the epoxy thermosets exhibited excellent flame-retardancy and passed V-0 rating of UL 94 test with LOI of 39.7% when the phosphorus content was only 0.5 wt%.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2020
·Vol. 137
·期 40
·49224
·
IF 2.52
Yu Sun,Yazhen Wang,Yingbo Qing,Xueying Wu,Zhen Shi
A novel 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO)-based Schiff base derivative, 6,6′-(1,4-phenylenebis (((3-hydroxyphenyl)amino) methylene)) bis (dibenzo [c,e] [1,2] oxaphosphinine 6-oxide) (SD), was synthesized and applied to polystyrene. The structure of terephthalaldehyde dihydroxymethane benzene and SD are characterized by Fourier-transform infrared (FTIR) spectroscopy, 1 H-nuclear magnetic resonance spectroscopy, and elemental analysis. The results of thermogravimetric analysis tests show that the residue of the SD/PS composites increased from 0.21 to 7.09% with the increase of SD content, indicated that the thermal stability of the SD/PS composites was significantly improved. The introduction of SD also efficiently ameliorated the flame-retardant property of SD/PS composites with limiting oxygen index increased by 33.15%, rated UL-94 vertical burning test V-0 rating, lower peak heat release rate, and total heat release. The mechanism of SD/PS composite was explored by scanning electron microscopy images and FTIR spectra of residue of SD/PS composites after calcination by muffle furnace. These tests prove that SD can be used as an effective polystyrene (PS) flame retardant.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
THERMOCHIMICA ACTA
·
2016
·
IF 1.938
Yan-Chong Zhang,Gui-Long Xu,Yun Liang,Jin Yang,Jian Hu
Phosphorus-containing epoxy resins were synthesized by o -cresol-novolac epoxy resin (CNE) and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) catalyzed by triphenyl phosphine (TPP). The reaction was characterized by FTIR, differential scanning calorimeter(DSC), Advanced Polymer Chromatography (APC) and HCl/acetone titration method. The results showed that the reaction of CNE and DOPO completed in 2 h at 130 °C with 1.5%TPP and the activation energy reduced from 162 kJ/mol to113 kJ/mol. The thermal properties and flame retardancy of the phosphorus-containing epoxy resins cured by phenol formaldehyde novolac resin(PN) were investigated by simultaneous thermal analyzer, cone calorimeter, limiting oxygen index (LOI) and vertical burning test (UL-94). The results revealed that the DOPO groups decomposed into phosphoric or polyphosphoric acid in air and decomposed into PO free radicals in nitrogen. The epoxy thermoset with 1.5% phosphorus content achieved UL94 V-1 rating and LOI 27% and the epoxy thermoset with 2.4% phosphorus content achieved UL94 V-0 rating and LOI 31%. The morphology of residues after cone calorimeter test was observed by scanning electron microscope (SEM). The results showed that the char of DOPO-CNE(2%P)/PN and DOPO-CNE(3%P)/PN present a compact and continuous surface.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2018
·Vol. 29
·期 11
·2774-2783
·
IF 2.137
Siqi Huo,Jun Wang,Shuang Yang,Haopeng Cai,Bin Zhang,Xi Chen,Qilei Wu,Lingfeng Yang
In this paper, a triazine-based flame retardant (TAT) was synthesized from cyanuric chloride and aniline. Its chemical structure was characterized by Fourier transform infrared (FTIR) spectroscopy, 1 H nuclear magnetic resonance, and elemental analysis. Two kinds of novel intumescent flame-retardant epoxy systems were obtained with the incorporation of TAT and 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) or hexa-phenoxy-cyclotriphosphazene (HPCP). The flame retardancy of the obtained epoxy samples was evaluated using limited oxygen index, vertical burning (UL94), and cone calorimeter tests. The results indicated that there was a synergistic effect between TAT and DOPO or HPCP. The flame-retardant mechanism was investigated by thermogravimetric analysis (TGA), thermogravimetric analysis/infrared spectrometry (TGA-FTIR) coupled with the morphology and chemical analysis of the char residues. During combustion, DOPO or HPCP decomposed to release phosphorus-containing free radicals with quenching effect. The morphology study showed that the introduction of DOPO or HPCP promoted the carbonization of epoxy matrix and the formation of a phosphorus-containing viscous char layer, while the pyrolysis gases derived from the decomposition of TAT caused the char layer to expand. The main reason of the promotion of flame retardancy of epoxy samples was that the simultaneous addition of TAT and DOPO or HPCP led to the formation of a compact and intumescent char layer that restricted the transfer of heat and combustible volatiles and simultaneously protected the underlying matrix.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
ACS Applied Polymer Materials
·
2025
·
IF 4.7
Yang Zhang,Xuan Wu,Yixiao Shi,Dan Liao,Jiaen Qian,Chuan Wu,Hong Dong,Qinghua Pan,Zhirong Qu,Yanjiang Song
A series of intrinsic flame-retardant epoxy resins were prepared by adding dual epoxy-functionalized polysiloxane (PDMS-GE) and DOPO to the epoxy resin (EP) of the DGEBA/DDM (60/20) system for curing reaction. The results showed that PDMS-GE and DOPO had excellent synergistic flame retardancy on EP, which was conducive to the formation of large-sized SiO2 particles and the formation of stable and dense char when the material burns. In this work, the LOI of the composite DGEBA/DDM/PDMS-GE/DOPO (60/20/5/5) reached 37.3, which was better than that of the material with only PDMS-GE or DOPO added and was 11.4 higher than that of neat EP. Compared with neat EP, the PHRR and THR of the CCT test were also reduced by 51.0 and 48.0%, respectively, and its UL-94 test reached the V-0 level. At the same time, the material also showed good hydrophobicity, and its water contact angle reached 102.63°. Based on the good dielectric properties and molecular chain flexibility of the PDMS structure, the dielectric constant of the prepared composite material at 14.2 GHz was reduced to 2.63, and the impact strength was also improved by about 33% relative to neat EP.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
FIRE AND MATERIALS
·
2024
·Vol. 48
·期 7
·752-764
·
IF 2
Zhengpeng Chen,Xin He,Zhengshuai Cao,Yunfan Li,Denglong Chen,Zhiwang Yang,Ziqiang Lei
With the wide application of epoxy resins in adhesives, electronic packaging materials, and aerospace fields, it is necessary to prepare high-performance flame-retardant epoxy resins to reduce the fire risk caused by their flammability. In this study, the rigid structure intermediate Schiff base (DMDA-SH) was synthesized by condensation reaction of syringaldehyde (SH) with O-Tolidine (DMDA). Then, DMDA-SH-DOPO, a novel P/N-structured biobased flame-retardant curing agent, was synthesized by addition reaction with 9,10-dihydro-9-oxaza-10-phosphame-10-oxide (DOPO) and was applied to the preparation of intrinsic flame-retardant epoxy resin. As expected, DMDA-SH-DOPO has good flame-retardant properties due to the synergistic action of N/P elements. Epoxy resin with only 2.5% DMDA-SH-DOPO (P = 0.16%) can pass the UL-94 V-0 test. Compared with DGEBA/DDM, DMDA-SH-DOPO-7.5's (P = 0.49%) peak heat release rate was reduced by 48.4% and the limiting oxygen index (LOI) reached 27%, making it a flame-retardant material. From the point of view of carbonaceous residue performance, the expansion height of carbon residue after DMDA-SH-DOPO-7.5 combustion is significantly increased, and the amount of carbon residue at 800°C is increased by 36.4%. In addition, appropriate DMDA-SH-DOPO can effectively improve the bending property of epoxy resin. This study provides a new idea for preparing renewable high-performance intrinsic flame-retardant epoxy resin.
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
高影响因子
WOOD SCIENCE AND TECHNOLOGY
·
2023
·
IF 3.4
Dong Youming,Fu Zhenyu,Yan Yutao,Shi Jingbo,Hughes Mark,Zhan Xianxu,Li Jianzhang
Poor dimensional stability, sensitivity to microorganisms, and flammability restrict the application of wood in certain areas where these properties are critical. Although furfurylation can improve the physical and mechanical properties of wood, the heat and smoke release of furfurylated wood during combustion are dramatic and need to be addressed. As a kind of halogen-free phosphorus flame retardant, 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and its derivatives exhibit excellent performance in polymer composites. In this study, DOPO was dissolved in furfuryl alcohol (FA) and used to modify wood. The effect of DOPO on the thermal stability, combustion behavior, and physical and mechanical properties of furfurylated wood was investigated. The chemical structure, morphology, and char residue after combustion were also characterized. The studies show that DOPO can react with the FA polymer and is incorporated and homogeneously dispersed in the wood structure. Compared to untreated wood, furfurylated wood has a much higher heat and smoke release during combustion. The addition of DOPO remarkably reduces the heat release of furfurylated wood, and this effect increases as the amount of DOPO increases. When the amount of introduced DOPO of furfurylated wood is 7%, its total heat release is reduced by 37.4% and becomes comparable to the untreated wood. However, DOPO does not suppress smoke production effectively. DOPO improves the thermal stability of furfurylated wood by promoting char formation and inhibiting the diffusion of oxygen and the escape of pyrolysis products. The addition of DOPO has little effect on the physical and mechanical properties of furfurylated wood. The results indicate that the combination of DOPO and furfurylation could be an efficient way to prepare highly stable and fire-resistant wood materials.
研究领域:
材料科学
·
化学
·
木材科学与技术
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2024
·
IF 6.3
Ying Zhou,Weidi He,Jiling Song,Dinghong Xu,Hongmin Wu,Jianbing Guo
The fabrication of ultralight high-performance flame-retardant composites significantly reduces fire risk for buildings. Flame retardation of porous polyvinyl alcohol (PVA) aerogels with directional arrangement is difficult. Herein, the polyvinyl alcohol/ 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide derivative/two-dimensional (2D) MXene (PVA/DiDOPO/MXene) composite aerogel was prepared by ice template one-way freezing process. PVA-DiDOPO4 composite aerogel with an oriented porous structure reaches the V-1 level at the UL-94 test. Moreover, the peak heat release rate (pHRR) value of PVA-DiDOPO4 reduces to 452.26 (W/g) from 482.88 (W/g) of pure PVA. In addition, PVA/DiDOPO/MXene composite aerogel has improved thermal decomposition properties such as the maximum decomposition temperature (T max1 ) of the PVA-DiDOPO4 sample attains 319.92 °C from pure PVA of 302.90 °C. The design strategy of PVA combined 2D MXene nanosheet and DOPO derivatives construct oriented porous composite aerogel paves the way for the fabrication and customization of ultralight flame-retardant polymer composites, which can be expected to be applied in construction and reduce fire risk.
研究领域:
材料科学
·
热分析
✓ 已验证
产品关联
DOI
高影响因子
Polymers
·
2018
·Vol. 10
·期 10
·1049
·
IF 2.935
Yufeng Ma,Xuanang Gong,Chuhao Liao,Xiang Geng,Chunpeng Wang,Fuxiang Chu
In order to improve the performance of phenolic foam, an additive compound of 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and Itaconic acid (ITA) were attached on the backbone of ethyl cellulose (EC) and obtained DOPO-ITA modified EC (DIMEC), which was used to modify phenolic resin and composite phenolic foams (CPFs). The structures of DOPO-ITA were verified by Fourier transform infrared spectroscopy (FT-IR) and nuclear magnetic resonance (1H NMR). The molecular structure and microstructure were characterized by FT-IR spectra and SEM, respectively. Compared with EC, the crystallinity of DIMEC was dramatically decreased, and the diffraction peak positions were basically unchanged. Additionally, thermal stability was decreased andTidecreased by 24 °C. The residual carbon (600 °C) was increased by 25.7%. With the dosage of DIMEC/P increased, theEavalues of DIMEC composite phenolic resins were increased gradually. The reaction orders were all non-integers. Compared with PF, the mechanical properties, flame retardancy, and the residual carbon (800 °C) of CPFs were increased. The cell size of CPFs was less and the cell distribution was relatively regular. By comprehensive analysis, the suitable dosage of DIMEC/P was no more than 15%.Keywords:DOPO;itaconic acid;ethyl cellulose;phenolic foams;composites
研究领域:
材料科学
·
化学工程
✓ 已验证
产品关联
DOI
PubMed
高影响因子
THERMOCHIMICA ACTA
·
2016
·
IF 1.938
Jianhua Hu,Jiye Shan,Jianqing Zhao,Zhen Tong
The isothermal curing kinetics of a flame-retardant epoxy resin containing DOPO (1.5 wt% of phosphorus) with hardener DICY was investigated using differential scanning calorimetry and oscillatory shear rheometry. The glass transition temperature T g increased with conversion α measured by DSC. When the curing temperature is lower than T g ∞ of the completely cured epoxy, the curing kinetics at high α became diffusion-control due to that cured epoxy restricted the diffusion of the reactants to decelerate curing. The modified Kamal model including the diffusion factor described curing conversion rate curves quite well. The curing degree θ was established with relative storage modulus, which was measured by the cyclic frequency sweep, and revealed that the transition from liquid to solid during curing appeared later with a slower rate than that for the conversion change, because the network began to form after formation of branched polymer chains. At the modulus transition time, the epoxy samples cured at different temperatures had the same conversion of 0.409, indicating that above this conversion of reactants the effective network was formed to bear the stress.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）