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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2015
·Vol. 133
·期 6
·
IF 1.768
Maolin Li,Yuhua Zhong,Zheng Wang,Andreas Fischer,Florian Ranft,Dietmar Drummer,Wei Wu
A novel flame-retardant composite was prepared by introducing a phosphorus-nitrogen flame retardant and DOPO-SiO 2 into PA6. DOPO-SiO 2 was synthesized successfully in a one-step process. PA6/OP1314/DOPO-SiO 2 achieved a UL 94 V-0 rating with an LOI value of 31%. The maximum mass loss rate of decomposition decreased significantly and char residue increased to 11.6 wt % compared with that of pure PA6. The compacted and dense char was formed due to the combination of the P-N flame retardant and DOPO-SiO 2 . The complex viscosity of PA6/OP1314/DOPO-SiO 2 increased considerably which tend to prevent the dripping phenomenon. The flame-retardant mechanism of PA6/OP1314/DOPO-SiO 2 was also investigated by Fourier transform infrared spectroscopy FTIR at different temperatures and the pyrolysis products were investigated by pyrolysis gas chromatography/ mass spectrum (Py-GC/MS). It was assumed that DOPO-SiO 2 and the hypophosphite of OP1314 possess excellent flame retardancy during the gaseous phase. Meanwhile, melamine and phosphate reacted with the pyrolytic products of PA6 to protect the matrix during the condensed phase. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133 , 42932.
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
·
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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2018
·Vol. 137
·期 1
·47411
·
IF 1.901
Zhun Li,Chuanchuan Liu,Weihong Cao,Qiang Yao
To take the advantage of reactivity of five-membered cyclic phosphorus compounds, 1,2,3-tri-phenyl-1,3,2-diazaphospholidine-2-oxide (TPDPO) was explored as a reactive flame retardant for epoxy resins (EPs). Through model compounds, it has been established that TPDPO selectively reacts with the secondary hydroxyl group and is inert toward both aryl amino groups and epoxide groups. The result of Soxhlet extraction supports that TPDPO is permanently bonded to the cured EPs. At a loading of only 8 wt % (0.74 wt % phosphorus), TPDPO enables the cured epoxy to achieve a UL-94 V0 rating. The thermogravimetric analysis–Fourier transform infrared analyses of the gaseous products suggest that the excellent flame retardancy of EP–TPDPO is partly due to the enhanced dehydration process of the epoxy. Also an increased char yield and the formation of a coherent char layer contribute to the good fire performance of EP–TPDPO. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137 , 47411.
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
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2021
·Vol. 32
·期 9
·3515-3522
·
IF 3.665
Yifan Xiao,Jiaxuan Li,Jun Wu,Liang Song,Yuxi Han,Zhongwei Wang,Qing Yu
Glass fiber reinforced polyethylene terephthalate (PET/GF) with enhanced flame retardancy was prepared with few-layer black phosphorus (BPs) for the first time. The performance of red phosphorus (RP) modified PET/GF was also investigated for comparison. Results show that PET/GF with 0.9 wt% BPs (PET/GF@BP-0.9) can eliminate the ignition of cotton by dripping. The addition of 2.7 wt% of BPs can make the PET/GF sample pass UL 94 V-0 classification, while a much higher of 6.3 wt% RP was needed to pass the same classification. Compared with neat PET/GF, the peak heat release rate (PHRR) and total heat release (THR) rate of PET/GF@BP-2.7 decreases ca. 52.5% and 34.8%, respectively. The studies of char residues reveal that BPs could act as a catalyst for char formation and the formed char could roughen the surface of GF and thus restrain the “wick effect.” Thermogravimetric analysis/infrared spectrometry shows that the addition of BPs significantly inhibited the release of gas-phase products. The attractive abilities of BPs as flame retardant provide a novel and effective way of PET/GF modification.
研究领域:
材料科学
·
化学工程
✓ 已验证
DOI
高影响因子
JOURNAL OF APPLIED POLYMER SCIENCE
·
2023
·Vol. 140
·期 46
·e54674
·
IF 3
Yingting Yin,Mao Feng,Wei Li,Jinbo Yao,Jiarong Niu
To improve the flame retardancy and solid content of waterborne polyurethane (WPU), AOT, and AOD series of WPU were synthesized and characterized. Carboxylic acid/nonionic composite units were used as hydrophilic groups, and OP550/THPO and OP550/DOPO-HQ combinations were used as flame retardant modifiers, respectively. The results revealed that the flame retardant-modified WPU emulsions still had excellent dispersion, stability, and fluidity. The UL-94 rating of modified WPU could reach V-0, and the AOD series samples had better flame retardancy than the AOT series, where AO 10 D 3 -WPU containing 3% DOPO-HQ had an limiting oxygen index value up to 30.5%. Besides, the peak heat release rate and total heat release of AO 10 D 3 -WPU were respectively decreased by 32% and 34%, compared with the control sample in the conical calorimetric test. The TGA, TG-IR, and SEM-EDS exhibited that the flame retardants functioned in the condensed phase by promoting carbon formation. The tensile strength of AOT series samples was excellent with a range of 15.84–27.47 MPa, while the elongation at break of AOD series samples was relatively high with a distribution of 850.8%–913.11%, which could be selected to suit the needs of different application scenarios.
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
COMPOSITES PART B-ENGINEERING
·
2025
·
IF 14.2
Yangming Zou,Jingfan Zhang,Xiaorong Guo,Yujie Kang,Xin Tong,Wei Liu,Xinqi Di,Jun Sun,Hongfei Li,Xiaoyu Gu,Sheng Zhang
Polycarbonate (PC) is a crucial engineering thermoplastic, but its impact strength is highly sensitive to notches, with even minor ones leading to significant reductions in mechanical performance. In this work, a crosslinked polysiloxane (VMQ) was synthesized and incorporated into PC to enhance both its toughness and flame retardancy. The introduction of VMQ greatly improved the notched impact strength and flame retardancy of PC. The addition of 5 wt% VMQ significantly enhanced the notched impact strength from 8.8 to 75.4 kJ/m 2 , representing an improvement of 756.8 %. Furthermore, the elongation at break and tensile toughness increased by 61.2 % and 46.5 %, respectively. Notably, even at −10 °C, the enhanced notched impact strength was almost fully retained. Additionally, the PC/5%VMQ composite achieved a UL-94 V-0 rating, with a limiting oxygen index (LOI) of 28.7 %, a 38.2 % reduction in peak heat release rate (PHRR), and a 13.9 % decrease in total smoke production (TSP). The toughening and flame-retardant mechanisms of VMQ were thoroughly investigated. This work provides an innovative approach to simultaneously improve the flame retardancy and toughness of PC.
研究领域:
材料科学
·
聚合物工程
✓ 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
JOURNAL OF APPLIED POLYMER SCIENCE
·
2021
·Vol. 139
·期 13
·51860
·
IF 3.125
Jia Chen,Li Rong,Wei Fang,Jiyan Liu,Xueqing Liu
A novel approach has been proposed to enhance the flame retardancy of ABS by a highly efficient intumescent flame retardant coating, which was prepared by aluminum- ethylene glycol methyl propionate cyclohexanediol phosphonate (EMPCP-Al), polyvinyl formal (PVFO) and melamine cyanurate with specific ratio. When the average thickness of coating achieved at 106 μm, the limit oxygen index value of ABS increased from 16.6% to 28.7%, its UL-94 rating reached V-0 level in the vertical burning test, and the peak value of heat release rate (PHRR) was decreased by 51.1% compared with that of pure ABS. TGA coupled with Fourier transform infrared spectroscopy was used to probe the degradation behavior of the flame retardant composites. In addition, the microscopic morphology and graphitization degree of the carbon layer which obtained after the thermal degradation of the flame retardant composites were investigated by scanning electron microscopy-energy dispersive X ray and Raman spectroscopy. Moreover, P element, N element and Al element in flame retardant coating exhibited benign synergistic flame retardancy in the gas phase and condensed phase. Furthermore, the flame retardant coating could effectively avoid the damage to intrinsic mechanical properties of ABS caused by high loading of flame retardant additives.
研究领域:
材料科学
·
阻燃技术
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）