JOURNAL OF APPLIED POLYMER SCIENCE
·
2022
·Vol. 139
·期 42
·e53041
·
IF 3.057
Yijun Zhang,Dawei Pan,Changfan Chang,Hua Liu,Zuozhen Liu
A highly reactive intrinsic epoxy flame retardant FREP was successfully synthesized via ring-opening reaction between DOPO and amino-tetrafunctional epoxy resin (AG-601), and the structure of the synthesized FREP was characterized by FTIR and MS. FREP was then introduced into the epoxy resin as an additive, aiming to improve fire safety. The flame-retardant properties and thermal stabilities of epoxy thermosets were investigated by limiting oxygen index (LOI), vertical burning test (UL94) and cone calorimetry (CONE). The results indicated that EP/FREP-4 thermoset passed UL94 V-0 rating with a LOI value of 34.6%, where the phosphorus content was 1.5 wt%. When compared with neat EP, the peak heat release rate (pk-HRR), total heat release (THR) and total smoke production (TSP) decreased by 63.1%, 42.6%, and 22.1%, respectively. Meanwhile, the lower av-EHC of EP/FREP thermosets indicated that FREP plays a significant role in gas-phase flame retardancy. Additionally, DMA analysis showed that FREP improved the crosslinking density of EP, which had little effect on the glass transition temperature ( T g ). Thermogravimetric analysis (TGA), Py-GC/MS analysis, and SEM were used to investigate the flame retardant mechanism. Excellent flame retardancy was attributed to phosphorus and nitrogen's synergistic effect in the gas and condensed phases.
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
·
2022
·
IF 16.744
Dan Xiao,Zi-Bo Wang,Uwe Gohs,Kathrin Harre,De-Yi Wang
In this work, the highly-efficient multifunctional bio-based fire retardant phenylphosphonic difurfurylamine (PPDF) was prepared successfully for poly(lactic acid) using furfurylamine and phenylphosphonic dichloride. Moreover, the structure of PPDF was analyzed by NMR, FTIR and MS. The fire safety, thermal, crystallization, rheological and mechanical properties of PLA/PPDF compounds were systematically tested by LOI, UL94, cone calorimeter test, TGA, DSC, polarizing optical microscope, rheometer, DMA and tensile properties. Surprisingly, only a very small loading of 0.8 wt% loading of bio-fire retardant PPDF could increase the LOI value of PLA from 19.0 % to 30.0 % and achieve V-0 rating in UL-94 vertical burning test. Moreover, PPDF not only reduced the molecular entanglement and viscosity of PLA, but also acted as a nucleating agent to increase crystallinity and crystallization rate of PLA matrix. More importantly, in the gas phase phosphorus, the PLA/PPDF compounds based on highly reactive benzene, phosphorus, phosphooxygen and phosphooxygen benzene radicals from the pyrolysis of PPDF had a highly-efficient fire safety. In the condensed phase, a relative stable residual char layer played a secondary role in the barrier. Thus, the total heat release and ignition time of PLA/PPDF compounds were evidently declined by 8.3 % and 10 s with only 0.8 wt% of PPDF loading.
研究领域:
材料科学
·
高分子化学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2016
·
IF 2.567
Yapeng Hu,Xiangmei Wang,Juan Li
An exfoliated montmorillonite (E-MMT) was prepared by introducing Ni2+ and melamine formaldehyde into layers of MMT. The E-MMT was applied to regulate the flame retardant properties of polypropylene (PP)/intumescent flame retardant (IFR) composites. The IFR used consists of ammonium polyphosphate (APP) and a charring agent, 1,3,5-triazine-2,4,6-trimorpholinyl (TTM). The results revealed that the E-MMT has good synergistic effect on flame retardancy of PP/IFR composites. The PP composites with 16 wt % IFR and 3 wt % E-MMT can pass the UL94 V-0 test. Moreover, the E-MMT not only improves the char residues of IFR and PP/IFR blend but also changes the micromorphology of char, turning the compact surface char produced by PP/IFR into microporous char. This microporous char is so good for isolating heat and mass between PP and the outside that a better flame retardant property is obtained.
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
POLYMER DEGRADATION AND STABILITY
·
2020
·
IF 4.032
Zhiyong Zhang,Dongsheng Li,Miaojun Xu,Bin Li
A novel phosphorus and nitrogen containing flame retardant named 1,4-bis(Diethyl methylenephosphonate) piperazine (BDEMPP) was synthesized. The chemical structures of BDEMPP were determined by Fourier transform infrared spectrum (FTIR), nuclear magnetic resonance (NMR) and gas chromatography-mass spectrometry (GC-MS). The flame retardant rigid polyurethane foams (FR-RPUFs) were prepared by one-pot and free foaming with incorporating BDEMPP/expanded graphite (EG) with polyether polyol and polymethylene polyphenyl isocyanate. The limit oxygen index (LOI), vertical burning (UL94) and cone calorimeter (CONE) test showed that the fire-retardant properties were improved due to the barrier effect of EG and residual char. With addition of 10 wt % EG and 15 wt % BDEMPP, RPUF/10EG/15BDEMPP passed UL94 V-0 with the LOI value of 25.7%. The thermogravimetric analysis (TGA) results revealed that the initial decompose temperature ( T 5% ) of RPUF/10EG/15BDEMPP was decreased compared with pure RPUF. However, the yield of residual char was increased from 0.35% for pure RPUF to 30.52% for RPUF/10EG/15BDEMPP at 800 °C. EG and BDEMPP had a slight influence on density and compression strength . The density and compression strength of pure RPUF was 45.42 kg m −3 and 213 kPa. As for RPUF/10EG/15BDEMPP, the density and compression strength was 44.18 kg m −3 and 180 kPa. The morphology and composition of residual char were investigated. The results demonstrated that the intact, compact and thick residual char with abundant of phosphorus and nitrogen was formed to enhance the flame retardancy and smoke suppression.
研究领域:
材料科学
·
高分子化学
·
消防安全工程
✓ 已验证
DOI
高影响因子
POLYMERS FOR ADVANCED TECHNOLOGIES
·
2019
·Vol. 31
·期 3
·461-471
·
IF 2.162
Zhongying Yao,Lijun Qian,Yong Qiu,Yajun Chen,Bo Xu,Jie Li
Based on bio-based furfural, a phosphorus-containing curing agent (FPD) was successfully synthesized, via the addition reaction between 9,10-dihydro-9-oxa-10 phosphaphenanthrene-10-oxide (DOPO) and furfural-derived Schiff base. Then, as co-curing agent, FPD was used to prepare flame retardant epoxy thermosets (EP) cured by 4, 4′-diaminodiphenyl methane. The incorporated FPD improved the flame retardancy and toughness of epoxy thermoset, simultaneously. When 5 wt% FPD was added into EP, the FPD/EP achieved 35.7% limited oxygen index (LOI) value and passed UL94 V-0 rating, meanwhile. In FPD/EP thermoset, the incorporated FPD reduced the thermal decomposition rate, increased the charring capacity, and inhibited the combustion intensity of epoxy thermoset. Through gas-phase and condensed-phase actions in weakening fuel supply, suppressing volatile combustion, and enhancing charring barrier effect, FPD decreased the heat release of burning epoxy thermoset, significantly. For the outstanding effectiveness on both flame retardancy and toughness, the study on FPD provides a promising way to manufacture high-performance epoxy thermoset.
研究领域:
材料科学
·
化学工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
INTERNATIONAL POLYMER PROCESSING
·
2023
·Vol. 38
·期 4
·518-527
·
IF 1.3
Yanbin Wang,Weiwei Zhang,Changlong Zhuang,Shengang Xu
In this study, a noncoplanar diimide diacid monomer (DIDA) was synthesized by direct condensation of trimellitic anhydride (TMA) with m-tolidine. The noncoplanar unit was incorporated into poly(amide-imide)s (PAIs) main chain by Yamazaki-Higashi phosphorylation of DIDA with various aromatic diamines. Encouragingly, all of the PAIs show good solubility in some common solvents such as N,N-Dimethylacetamide (DMAc), N-methyl-2-pyrrolidinone (NMP), and m-cresol. In addition, the soluble PAIs show good optical transmittances of beyond 85 % at 500 nm due to the decreased crystallization ability. On the other hand, PAIs possess good mechanical properties with tensile strengths of 72–90 MPa and tensile moduli beyond 2 GPa. Meanwhile, the designed PAIs also exhibit excellent thermal properties: their glass transition temperatures ( T g ) range from 278 to 314 °C, initial decomposition temperatures (5 % weight loss temperatures, T 5wt% ) are beyond 470 °C, coefficients of thermal expansion (CTE) are below 10 ppm/°C. The excellent mechanical and thermal properties are due to the strengthened hydrogen bonding interaction among the amide groups. Therefore, it is believed that incorporating noncoplanar unit and amide group into the polymer main chain at the same time can simultaneously improve processability, optical transparency, mechanical and thermal properties. Furthermore, it is worth noting that the char of PAI at 800 °C is as high as 72.5 %, which is one of the highest known values. When PAI was incorporated into epoxy resin, the blend passed UL94 V-0 rating due to the high charring capability of PAI.
研究领域:
聚合物科学
·
材料科学
·
化学工程
·
消防安全
✓ 已验证
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2016
·
IF 3.12
Shuang Yang,Qiaoxin Zhang,Yefa Hu
A novel halogen-free flame retardant (DTB) containing phosphorus, nitrogen and boron was successfully synthesized. The chemical structure of DTB was characterized by Fourier transform infrared spectroscopy (FTIR), 1 H and 31 P nuclear magnetic resonance (NMR). DTB was then blended with diglycidyl ether of bisphenol-A (DGEBA) to prepare flame-retardant epoxy resins . Thermal properties, flame retardancy and combustion behavior of the cured EP thermosets were investigated by thermogravimetric analysis (TGA), limited oxygen index (LOI) measurement, UL94 vertical burning test and cone calorimeter test. The results indicated that DTB significantly improved the flame retardancy as well as smoke inhibition performance of EP/DTB thermosets. Compared with the neat EP thermoset, the LOI of EP/DTB-3 thermoset was increased to 35.6% and the sample reached UL94 V-0 rating; the average of heat release rate (av-HRR), total heat release (THR) and total smoke production (TSP) of EP/DTB-3 thermoset were decreased by 33.3%, 33.0% and 35.5%, respectively. TGA results indicated that the char yields of EP/DTB thermosets were increased by 45.1–72.8% compared with that of the neat EP thermoset. The FTIR, SEM-EDX and Py-GC/MS results indicated that DTB contributed to form intumescent and glassy char layers and decomposed to generate free radicals with quenching effect. DTB was effective radical trapper as well as efficient charring agent for epoxy resin and exerted flame-retardant effect in gaseous and condensed phases simultaneously.
研究领域:
材料科学
·
高分子化学
·
消防安全工程
✓ 已验证
产品关联
DOI
高影响因子
HIGH PERFORMANCE POLYMERS
·
2018
·
IF 1.047
Shuang Yang,Yefa Hu,Qiaoxin Zhang
In this article, a phosphorus–nitrogen-containing flame retardant (DOPO-T) was successfully synthesized by nucleophilic substitution reaction between 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and cyanuric chloride. The chemical structure of DOPO-T was characterized by Fourier transform infrared spectroscopy, proton nuclear magnetic resonance (NMR) and phosphorous-31 NMR, and elemental analysis. DOPO-T was then blended with diglycidyl ether of bisphenol-A to prepare flame-retardant epoxy resins. Thermal properties, flame retardancy, and combustion behavior of the cured epoxy resins were evaluated by differential scanning calorimetry, thermogravimetric analysis, limited oxygen index (LOI) measurement, UL94 vertical burning test, and cone calorimeter test. The results indicated that the glass transition temperature (Tg) and temperature at 5% weight loss of epoxy resin (EP)/DOPO-T thermosets were gradually decreased with the increasing content of DOPO-T. DOPO-T catalyzed the decomposition of EP matrix in advance. The flame-retardant performance of EP thermosets was significantly enhanced with the addition of DOPO-T. EP/DOPO-T-0.9 sample had an LOI value of 36.2% and achieved UL94 V-1 rating. In addition, the average of heat release rate, peak of heat release rate, average of effective heat of combustion, and total heat release (THR) of EP/DOPO-T-0.9 sample were decreased by 32%, 48%, 23%, and 31%, respectively, compared with the neat EP sample. Impressively, EP/DOPO-T thermosets acquired excellent flame retardancy under low loading of flame retardant.
研究领域:
材料科学
·
高分子化学
·
消防安全工程
✓ 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）