INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Qinqin Luo,Yanchao Yuan,Chunlei Dong,Haohao Huang,Shumei Liu,Jianqing Zhao
The flame retardancy, thermal, and mechanical properties of the cured epoxy resins are difficult to be simultaneously improved. In the present work, a novel DPPA-based curing agent, 10-[(4-hydroxyphenyl)(4-hydroxyphenylimino)methyl]-5,10-dihydrophenophosphazine 10-oxide (H-DPPA), is successfully synthesized to serve as a co-curing agent of 4, 4′-diaminodiphenylmethane (DDM) for bisphenol A diglycidyl ether (DGEBA) epoxy resin. With the aid of 3.0 wt % of H-DPPA, the cured epoxy resin, in which the phosphorus content is as low as 0.22%, passes V-0 rating of UL-94 test with limiting oxygen index (LOI) of 31.8%. The high flame retardancy of epoxy resin modified by H-DPPA originated mainly from the formation of intumescent char layer during combustion. This new type of flame retardant containing both phosphine oxide structure and nitrogen moieties provides epoxy resins with excellent integrated performances.
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
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Junling Wang,Chao Ma,Peilong Wang,Shuilai Qiu,Wei Cai,Yuan Hu
A novel phosphorus-containing compound (DOPO-THPO) is synthesized via the Atherton-Todd-reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and trihydroxymethylphosphine oxide (THPO), and then employed as flame retardant for diglycidyl ether of bisphenol A/4-4 diaminodiphenylmethane epoxy resin (DGEBA/DDM). Based on the ultra-low phosphorus loading, the highly efficient flame retarded epoxy resin (EP) systems are successfully established in this work. Remarkable improvements in the limited oxygen index (LOI) values and UL-94 rating of flame retarded EP systems are observed. In detail, when the phosphorus content is only 0.33 wt%, the EP composite receives V-0 rating in the UL-94 vertical burning test with LOI value of 30%. Heat release of EP composites is obviously inhibited with the formation of intumescent char residue. Furthermore, TG-IR result of DOPO-THPO shows the generation of phosphorus containing products, which may provide a gaseous phase flame retardant function on EP. This work may open the new door for the construction of highly efficient flame retardant EP system based on the ultra-low phosphorus loading.
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
POLYMER
·
2024
·
IF 4.1
Yi Zheng,Zongsheng Liu,Bangdong Ge,Meng Ma,Si Chen,Yanqin Shi,Huiwen He,Yulu Zhu,Xu Wang
The incorporation of traditional low molecule bromine flame retardants can enhance the flame retardancy of polycarbonate (PC), yet their poor compatibility with PC impairs its transparency and mechanical properties. Here, brominated polycarbonate (B 50 PC) was synthesized by interfacial polycondensation method using bisphenol A, tetrabromobisphenol A, and triphosgene. The number average molecular weight ( M n ) of B 50 PC reached 14,600, and compared to the low molecule bromine flame retardant tetrabromobisphenol A (TBBPA), its initial decomposition temperature increased by 38.7 % under air atmosphere. The PC composites containing 5 wt% B 50 PC achieved the V-0 rating in the UL-94 test, with LOI increased by 10.3 %. At the same time, the peak heat release rate (PHRR) was decreased by 28.6 % and the ignition time (TTI) was delayed by 21.3 %. Compared with that of samples with TBBPA, the composite with the same amount of B 50 PC maintained the original elongation at break of PC and the transmittance remained at 84.9 %. In summary, the composites with B 50 PC maintains outstanding transparency and mechanical properties while enhancing the flame retardancy. This work has developed a high molecular bromine flame retardant that combines flame retardancy and transparency, offering a strategy for expanding the application of PC in the electronics, construction, and aerospace sectors.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2018
·
IF 3.193
Junjing Zhao,Xu Dong,Shan Huang,Xiujuan Tian,Liang Song,Qing Yu,Zhongwei Wang
Two phosphorus-containing flame retardants , (bis(4-hydroxyphenyl)methyl)diphenyl phosphine oxide (DPO–PHE) and 1-(bis(4-hydroxyphenyl)methyl)-9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO–PHE) were synthesized and characterized. The two target compounds both were used as a flame retardant and a co-curing agent of 4,4′-diaminodiphenylsulfone of bisphenol A diglycidyl ether to prepare flame-retardant epoxy resins (EP/DPO–PHE and EP/DOPO–PHE). The thermal and flame-retardant properties of the thermosets were investigated by thermogravimetric analysis (TGA), limited oxygen index (LOI) measurement, and UL-94 vertical burning testing (UL-94). The results indicated that both flame retardants can improve the flame retardancy of epoxy thermosets. TGA results indicated that the char yields of EP/DPO–PHE–P-0.9 and EP/DOPO–PHE–P-0.9 thermosets were increased from 19.1% of EP/P-0 to 25.3% and 27.8%, respectively. Compared with that of EP/P-0, the LOI of the EP/DPO–PHE–P-0.5 thermoset increased from 23.7% to 30.1%, and the sample reached UL-94 V-0. Meanwhile, the LOI of the EP/DOPO–PHE–P-0.7 thermoset increased from 23.7% to 28.9%, and the sample reached UL-94 V-0. Cone calorimetry test, scanning electron microscopy of burning residues, and pyrolysis–gas chromatography/mass spectrometry indicated that both flame retardants mainly act through the gas–phase mechanism. In addition, no condensed-phase activity of DPO–PHE was observed, whereas the condensed-phase activity of DOPO–PHE was negligible. Immersion experiments showed that the water absorption activity of flame retardant epoxy resins fluctuates. Compared with DOPO–PHE, DPO–PHE was more effective as a higher flame-retardant and exhibited better characteristics for improving the T g , thermal stability, and water absorption of modified resins.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 30
·期 8
·1989-1995
·
IF 2.162
Qinqin Luo,Yulin Sun,Biao Yu,Chengpeng Li,Jiangli Song,Dexin Tan,Jianqing Zhao
The flame-retarded epoxy resin with improved thermal properties based on environmentally friendly flame retardants is vital for industrial application. Hereby, a novel reactive-type halogen-free flame retardant, 10-(3-(4-hydroxy phenyl)-3,4-dihydro-2H-benzo[e] [1,3] oxazin-4-yl)-5H-phenophosphazinine 10-oxide (DHA-B) was synthesized via a two-step reaction route. Its structure was characterized using 1 H, 13 C, and 31 P NMR and HRMS spectra. For 4,4′-diaminodipheny ethane (DDM) and diglycidyl ether of bisphenol A (DGEBA)-cured systems, the epoxy resin with only 2 wt% loading of DHA-B passed V-0 rating of UL-94 test. Significantly, its glass transition temperature ( T g ) and initial decomposition temperature ( T 5% ) were as high as 169.6°C and 359.6°C, respectively, which were even higher than those of the corresponding original epoxy resin. Besides, DHA-B decreased the combustion intensity during combustion. The analysis of residues after combustion suggested that DHA-B played an important role in the condensed phase.
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 Materials Chemistry A
·
2024
·
IF 10.7
Kunpeng Song,Keshan Zhang,Xue Bi,Boyou Hou,Ye-Tang Pan,Xingyao Li,Jiyu He,Rongjie Yang
Metal–organic framework (MOF)-based functionalized porous liquids are promising candidates for efficient functional species, owing to their better storage stability, higher dispersibility, and convenient processing properties than solid MOF-based fillers. However, the structural design and synthesis strategy for such porous liquids have been a challenge so far. Herein, a porous flame retardant (UiO-66-NH2@PA@OAPS, U@PA@OA) was designed using UiO-66-NH2 as a precursor, 3-phosphonopropanoic acid (PA) as a flame-retardant ligand, and octa(aminophenyl) polyhedral oligomeric silsesquioxane (OAPS) as a modifier through post-synthesis modification strategies, such as ligand replacement, defect engineering, and surface modification. Later, it was utilized as a rigid guest and polysiloxane was employed as a mobile phase and a hydrophobic component to manufacture functionalized porous liquids (UiO-66-NH2@PA@OAPS PLs, U@PA@OA PLs). Advanced U@PA@OA PLs present favorable storage stability as well as compatibility with polyurea components. Impressively, U@PA@OA PLs with a 10 wt% loading (2 wt% U@PA@OA content) in polyurea can improve the limiting oxygen index value of the composites to 26.9% and pass the V-0 rating in the UL-94 test. Moreover, the peak of heat release rate, total heat release, and total smoke production of the polyurea composites are reduced by around 53.7, 36.3, and 34.0%, respectively, compared to neat polyurea. Moreover, the mechanical properties, impact resistance, and chemical resistance of PLs modified polyurea composites are also significantly enhanced. This work not only motivates researchers to design functionalized porous liquids rationally, but it is also expected to expand the application of composites in other potential fields.
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
POLYMER DEGRADATION AND STABILITY
·
2014
·
IF 2.633
Liqiang Gu,Guoan Chen,Youwei Yao
Two novel halogen-free flame retardants , DP-DDE and DP-DDS, were synthesized via a one-pot procedure based on the Pudovik reactions between 9,10-dihydro-9-oxa-10-phosphaphenanthrene 10-oxide (DOPO) and imines directly resulting from the condensation reactions of 3-methoxy-4-hydroxybenzaldehyde with two typical curing agents , 4,4′-oxydianiline (DDE) and 4,4′-diaminodiphenylsulfone (DDS), respectively. The fire-resistant properties of DP-DDE or DP-DDS modified epoxy resins (2,2-bis(4-glycidyloxyphenyl)propane) with 4,4′-methylenedianiline as hardener were been investigated by UL-94 vertical test. Their high flame-retarding performance has been found: the epoxy thermosets with a relatively low addition amount of DP-DDE or DP-DDS (on the account of phosphorus content of 0.75 wt.% or 0.73 wt.%) can reach UL-94 V-0 flammability rating. These thermosets demonstrated excellent thermal stability, high glass transition temperature ( T g > 135 °C) and high char yields (>22% at 800 °C). Moreover, the thermal degradation kinetics of the flame retardants and their corresponding epoxy thermosets were studied based on Kissinger, Ozawa and FWO methods by thermogravimetric analysis .
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
CHEMICAL ENGINEERING JOURNAL
·
2019
·
IF 8.355
Peng Lu,Ze-Yong Zhao,Bo-Ren Xu,Ying-Ming Li,Cong Deng,Yu-Zhong Wang
Thermoplastic polyamide elastomers (TPAEs) are a new and important member of the thermoplastic polymer elastomers (TPEs) family, and the flame retardation of TPAEs is a big challenge due to the deterioration of their properties. In this work, we have successfully designed and synthesized the first “inherently” flame-retardant TPAE by introducing a phosphorus-containing group (DDP) into the macromolecular chains through P-C covalent bonds. The properties of TPAEs can be regulated by controlling the contents and distribution of polyamide (PA) segments as a hard segment, polyethylene glycol (PEG) as a soft segment, and DDP as a flame retardant unit during the synthetic process. The resulting TPAEs can achieve a V-0 rating in the UL-94 test and a limiting oxygen index of higher than 35.0%. The enhancement of flame retardancy is attributed to the droplet-promoting mechanism and the free radical quenching effect in the vapor phase. Unfortunately, the density of the inter-chain H-bonding and crystallinity of the PA segments regions decreased with the incorporation of DDP groups, which lead to the decrease of the tensile properties of TPAEs. However, the samples with high flame retardancy are still able to maintain 400% of elongation at break and 20 MPa of tensile strength, respectively, which have better comprehensive properties than typical commercial TPEs (Pebax®). Therefore, this novel inherently flame-retardant thermoplastic polyamide elastomer will exhibit a wider range of application potentials.
研究领域:
材料科学
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF NON-CRYSTALLINE SOLIDS
·
2021
·
IF 3.531
Guangxu Bo,Xiaoling Xu,Xiaoke Tian,Jiao Wu,Xin He,Li Xu,Yunjun Yan
Silica aerogel (SA) was successfully synthesized by sol-gel method under ambient pressure drying. The first and second type silica aerogel/castor oil-based flame retardant rigid polyurethane foam (SA/RPUF) composites were then fabricated via blending SA into the interior of RPUFs and coating SA onto the surface of RPUFs, respectively. Properties of the composites, including density, thermal conductivity, compressive strength, specific modulus, hydrophobicity, chemical component, morphology, thermal stability, limiting oxygen index (LOI), UL-94 tests, cone calorimetry (CC) testing, and char residues stability were characterized. The results showed RPUFs with larger cell size via coating SA onto their surface had cracking properties on the physical and flame retardancy, especially RPUF-4. Compared with neat RPUF, RPUF-4 obtained greatly improved properties with specific modulus an increment of 107.62%, the LOI value an increase of 50.76%, the first and second peak heat release rates with respective reduction of 52.43% and 40.78%, and respective 56.86% and 47.82% reduction in the first and second peak smoke production release rates. Thus, this study shows RPUFs with larger cell size via coating SA onto their surface have great potential for fire safety as building insulation materials.
研究领域:
材料科学
·
高分子科学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 44
·e54608
·
IF 3
Song Wang,Lingchen Meng,Qi Chen,Sanxi Li,Ailing Zhang
The synthesis and application of the bio-derived flame retardant can meet the current requirements for the high-efficient and sustainable development of flame retardants. Therefore, using phytic acid (PA), 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO), and piperazine as raw materials, a PA-derived flame retardant (PAPDOPO) was prepared. Fourier transform infrared spectroscopy and x-ray diffraction techniques were applied to characterize the structure of the PAPDOPO. In the prepared flame-retardant epoxy resin (FEP), PAPDOPO showed high flame retardancy. When 4% PAPDOPO was added into epoxy resin (EP), the prepared FEP (EP-PAPD-4) passed the V-0 level in the UL-94 test, and the limited oxygen index value of EP-PAPD-4 reached 35.3%. Microcombustion calorimetry test was also applied to demonstrate the performance of PAPDOPO. The peak heat release rate of EP-PAPD-4 was reduced by 30.4% compared with that of the pure EP. Due to the low addition amount of PAPDOPO in FEP, the mechanical properties of the FEP using PAPDOPO as flame retardant were hardly decreased compared with pure EP.
研究领域:
材料科学
·
化学工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2022
·Vol. 33
·期 10
·3490-3500
·
IF 3.348
Wu Zhang,Weikang Xia,Yasheng Shi,Changlin Zhou,Ran Chen,Lei Wang,Jinqing Qu
Flame-retarded epoxy thermosets are highly desirable for electronics-related basic materials in the new-generation information applications. Herein, a DOPO-anchored benzothiadiazole flame retardant, namely DOPO-BTD , is designed and synthesized for P/N/S synergistic flame-retarded epoxy thermosets. DOPO-BTD possesses good thermal stability and excellent compatibility with the epoxy matrix. As reflected by UL 94 test, the DOPO-BTD coated EP passes the V0 rating and achieves a higher LOI value of 34.6% at ultralow P content of 0.39 wt%. The investigation of the DOPO-BTD -triggered P/N/S synergistic flame-retarded effect by thermal images further validated the flame retarded efficacy and dramatic inhibition of the flame. Meanwhile, the incorporation of 4.8 wt% DOPO-BTD into the epoxy matrix, the PHRR, THR, SPR, TSP, and COP are significantly decreased by 37.97%, 27.44%, 25.49%, 19.83%, and 31.70%, respectively. Additionally, the fire growth index (FGI) is sharply dropped 26.06%. Moreover, the TGIR and TGMS results convince the flame-retarded mechanism of DOPO-BTD through the combination of the gas-phase and condensed-phase pathways. The P/N/S synergistic DOPO-BTD can serve as a promising flame retardant for efficiently fabricating the flame-retarded epoxy thermosets, and this study sheds light on the development of multiple elements synergistic flame-retardants for functional polymers with great application potential.
研究领域:
材料科学
·
化学工程
·
高分子科学
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Yubo Chen,Siyuan He,Yaxun Huang,Liping Jin,Lei Liu,Yu Guan,Congke Gu,Chenpeng Ji,Wenwen Guo
With growing emphasis on environmental protection and sustainable development, developing high-performance bio-based epoxy resins has become a central focus to reduce reliance on petroleum-derived curing agents. This study presents a novel approach by synthesizing three types of cardanol-based flame-retardant epoxy curing agents, C1-DPP-MA, C2-PDP-MA, and C3-POC-MA, as sustainable bio-based alternatives to conventional petroleum-derived curing agents. The structures of these curing agents were confirmed through FTIR and NMR spectroscopy. Flame-retardant epoxy resins (DGEBA/C1-DPP-MA (EP1), DGEBA/C2-PDP-MA (EP2), and DGEBA/C3-POC-MA (EP3)) were prepared via thermal polymerization, with DGEBA/MHHPA (EP0) serving as a control. Kinetic analysis revealed that the curing activation energies of EP1, EP2, and EP3 were all higher than that of EP0, which can be attributed to the steric hindrance of the cardanol-derived curing agent molecules. Among the three cardanol-based epoxy resins, EP1 and EP2 demonstrated superior flame retardancy compared to EP3, with Limiting Oxygen Index (LOI) values of 28 % and 27 %, respectively. UL-94 tests showed that EP1 achieved V -0 ratings. Cone calorimetry tests further confirmed their enhanced flame retardancy, with EP1 and EP2 showing reductions in peak heat release rate (PHRR) by 52.8 % and 37.8 %, respectively, and significant decreases in total heat release (THR). Additionally, the cardanol structure's long, flexible side chains improved toughness and elongation at break in EP1. Moreover, a carbon nanofiber (CNF)-reinforced composite (EP1CF) was synthesized from EP1, significantly enhancing its thermal stability, flame retardancy, and mechanical properties. This study introduces a promising approach for designing bio-based epoxy resins with superior overall properties, contributing to the advancement of environmentally friendly flame-retardant materials by synergistically incorporating CNFs with cardanol-based curing agents.
研究领域:
材料科学
·
高分子化学
·
环境科学
·
化学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）