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 THERMAL ANALYSIS AND CALORIMETRY
·
2020
·Vol. 145
·期 6
·3067-3075
·
IF 2.731
Zhang Kailun,Wu Hongjuan,Wang Tian,Yao Meng,Xie Jixing,Jiao Yunhong
A phosphazene-based flame retardant (PBFA) was synthesized by hexachlorocyclotriphosphazene and N- aminoethylpiperazine. To improve the flame retardancy of polypropylene (PP), PBFA and pentaerythritol derivatives (PEPA) were mechanically mixed to form a water resistance intumescent flame retardant (IFR). The flammability and thermal properties of the PP composites were analyzed by vertical burning test (UL-94), limit oxygen index, thermogravimetric analysis (TGA) and cone calorimeter test (CCT). The results indicate that there was a synergistic effect between PBFA and PEPA at a suitable mass ratio. When the mass ratio of PBFA/PEPA was 2:1, the PP composites can successfully achieve UL-94 V 0 rating. Compared with pure PP, the peak heat release rate and the total heat release were decreased by 75.40 and 15.38%, respectively; moreover, the total smoke production decreased by 22.11% during 0–465 s. The residual char after CCT was characterized by Fourier transform infrared spectrometer (FTIR). A strong pyrophosphate absorption peak was found in FTIR, indicating that the IFR mainly played a flame-retardant mechanism in the condensed phase.
研究领域:
材料科学
·
高分子化学
✓ 已验证
DOI
高影响因子
CELLULOSE
·
2020
·Vol. 27
·期 14
·8369-8383
·
IF 4.21
Zhang Qiu-yan,Liu Xiao-hui,Ren Yuan-lin,Zhang Yan-guang,Cheng Bo-wen
Abstract A novel phosphoramidate salt fire retardant (FR) with high phosphorus–nitrogen (P–N) content, tris(2-aminoethyl)amine phosphoramidate salt (TAEAPA), was synthesized by a simple design philosophy. A three-arm star-like structure FR with a high level of P or N content was obtained. Phosphorus and nitrogen contents of TAEAPA increased up to 8.6 at% and 14.5 at%, respectively. Subsequently, TAEAPA was employed to finish lyocell fibers through the classical dip-dry-cure technique. Consequently, the thermal stability and fire retardancy of finished lyocell fibers were improved significantly, as evidenced by thermogravimetric and vertical flammability test. Finished lyocell fibers exhibited higher char residues (39.2 wt%) and lower degradation rate (0.6%/°C) under nitrogen atmosphere. Besides, lyocell fabrics finished by 300 g/L of TAEAPA finishing solution only had a char length of 53 mm when exposed to flame more than 60 s, and immediately extinguished after the removal of flame. Thermogravimetry-infrared and pyrolysis gas chromatography/mass spectrometry coupled techniques confirmed that the high contents of P and N included in TAEAPA played a good synergistic effect on both condensed and gaseous phase during the thermal pyrolysis process of lyocell fibers. Graphic abstract
研究领域:
材料科学
·
纺织工程
·
高分子化学
✓ 已验证
产品关联
DOI
高影响因子
POLYMER DEGRADATION AND STABILITY
·
2023
·
IF 5.9
Zexi Zhao,Zhiyong Zhang,Caiying Sun,Miaojun Xu,Bin Li
In this paper, an innovative macromolecular phosphorus-nitrogen containing flame retardant (PDPSB) was successfully designed and synthesized to investigate its impact on the flame retardancy, burning behavior, thermal stability, mechanical properties of polycarbonate (PC) composites. Furthermore, an in-depth exploration of the potential flame-retardant mechanism was conducted. The combustion results indicated that PC-3 with 3 wt% PDPSB reached V-0 rating in UL-94 test and showed a high limiting oxygen index (LOI) of 33.0 %. Compared to pure PC, the values for peak of heat release rate (PHRR), total heat release (THR) and total smoke production (TSP) of PC-3 were decreased by 37.9 %, 11.1 % and 4.9 %, respectively. It was noteworthy that the amount of char residue for PC-3 was raised from 7.4 % for pure PC to 15.8 % with increasing 113.5 %. The thermogravimetric analysis (TGA) results under N 2 atmosphere revealed that PDPSB possessed preferable thermal stability with initial decomposition temperature ( T initial ) of 342.6 °C and higher char residue yield of 48.4 %. With increasing the amount of PDPSB, the maximum mass loss rate ( R peak ) was reduced and the char residue yield was increased for PC/PDPSB composites. In addition, the mechanical properties of PC/PDPSB composites were well maintained due to the good compatibility and dispersion between PDPSB and PC matrix. The tensile, flexural and izod impact strength of PC-3 were weakened by 4.3 %, 1.7 % and 16.8 % in comparison of pure PC, respectively. Based on the investigation into the flame-retardant mechanism of PDPSB, the excellent flame retardance of PC/PDPSB composites has been validated. In gaseous, the release of pyrolysis gases was suppressed and active radicals were captured by generated phosphorus free radicals. In condensed phase, the stable char residue with phosphorus and nitrogen elements acted as a barrier to hinder heat, flame and oxygen. This high-efficient single-component multifunctional additive presented a novel approach to the development of fire-resistant polymers with enhanced performance characteristics.
研究领域:
材料科学
·
阻燃技术
✓ 已验证
产品关联
DOI
高影响因子
CELLULOSE
·
2022
·Vol. 29
·期 3
·2063-2076
·
IF 6.123
Li Na,Chen Panpan,Liu Dongni,Kang Gaowei,Liu Liu,Xu Liyun,Yu Jianyong,Li Faxue,Wu Dequn
Cotton fabric has a wide application due to its hygroscopicity, air permeability, and large production of cotton fiber used to make the fabric. However, cotton materials are a safety hazard during its application because of flammability (limiting oxygen index is about 18%). In order to improve the flame retardancy of cotton fibers and reduce the damage of its mechanical properties, novel P/Si based flame retardant (PFR) nanoparticles were synthesized by one-step radical polymerization. Vinyl phosphoric acid and tetramethyl divinyl disiloxane were introduced into the nanoparticles. The structure, morphology and thermal stability of PFR was characterized by fourier transform infrared spectroscopy (FT-IR), field emission scanning electron microscopy (FE-SEM), thermogravimetric analysis test (TGA). Durable flame retardant cotton fibers were prepared by dip-coating and plasma induced crosslinking methods. Micro-calorimeter (MCC) characterization showed that the peak of heat release rate (pHRR) and the total heat release (THR) were reduced by 47.3% and 29.8% for modified cotton fibers compared with pure cotton fibers. Limiting oxygen index (LOI) of modified cotton fibers was increased to 27%. The residue carbon of modified cotton fibers was 19.0% at 700 °C, while the value of pure cotton fibers was 3.0%. Besides, durability of the modified cotton fibers was approved by cyclic washing test. In addition, flame retardant mechanism was revealed by collecting and analyzing condensed and gaseous pyrolysis products. The data of FE-SEM for residue carbon, FT-IR spectra of products at different pyrolysis temperatures and pyrolysis gas chromatography mass spectrometry (Py-GC–MS) showed that PFR was a synergistic flame retardant contained barrier and quenching effecting applied on cotton materials. Graphical abstract Novel phosphorus-silicon based nanoparticles were synthesized by one-step radical polymerization and applied to improve the flame retardant of cotton materials by dip-coating and plasma induced crosslinking.
研究领域:
材料科学
·
纺织工程
✓ 已验证
DOI
高影响因子
CHEMICAL PHYSICS LETTERS
·
2020
·
IF 2.029
Xingkun Zhu,Nan Zou,Hongchang Pang,Peng Tian,Guiling Ning
A high-efficient composite of flame retardant (CFR) composed of an aluminum hydroxide (ATH) core and an aluminum phosphate (AP) flower-like shell was synthesized by an in-situ growth method, which is low cost and easy-to-handle. It has been demonstrated that flame retardancy and smoke suppression of (ethylene-vinyl acetate) EVA/CFR were enhanced compared to EVA/ATH attributed to the high-efficiency heat barrier and gas isolation of ceramic char residues mainly composed of Al 2 O 3 porcelain agents and AlPO 4 sintering aids. Thus, the novel hierarchical core-shell AlPO 4 @Al(OH) 3 might supersede the ATH as flame retardants.
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
·
2016
·
IF 3.12
Panyue Wen,Xiaming Feng,Yongchun Kan,Yuan Hu,Richard K.K. Yuen
In this research, a novel triazine-based polymeric flame retardant (TBMC) was synthesized. The intumescent flame retardant (IFR) system was formed by combining. TBMC with ammonium polyphosphate (APP), and is applied to retard the combustion of polypropylene (PP). PP/IFR samples (APP/TBMC = 3/1 to 1/1) achieved increased limited oxygen index (LOI) values and passed the vertical burning (UL-94) V-0 rating. Herein, cone calorimeter tests show that the heat release rate (HRR) and fire growth index (FGI) of PP/APP/TBMC blends were obviously decreased compared to those of pure PP and PP with 25 wt% APP. The thermogravimetric analytical (TGA) results showed that the TBMC/APP system could improve the thermal and thermal-oxidative stability of the char residues. The char residues were further investigated by visual observation and scanning electron microscopy (SEM). The compact char residues formed hindered the transfer of gas and heat during combustion, ultimately endowed PP/IFR systems improved flame retardancy.
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
RSC Advances
·
2014
·Vol. 4
·期 64
·34161-34167
·
IF 3.708
Wenpeng Ding,Juan Li,Kang Tao
Solid super acid (SSA) as a kind of green catalyst was introduced into conventional intumescent flame retardant (IFR)/ethylene-vinyl acetate (EVA) composites to increase their flame retardant efficiency. The IFR used was a combination of ammonium polyphosphate coated by melamine resin (MAPP) and pentaerythritol (PER) with weight ratio at 3 : 1. TGA results showed that the SSA promoted the reaction between MAPP and PER. The thermal degradation temperature of the IFR/EVA composites with 1.5 wt% SSA was significantly increased by 95 °C compared to that of IFR/EVA. The UL 94 V-0 rating can be achieved for EVA composites with 13 wt% total amount of IFR and SSA, while the EVA composites with individual 13 wt% IFR only passed the UL-94 V-2 rating. The char residues at 800 °C of SSA/IFR/EVA composites were 5.8 wt%, which was higher than 2.4 wt% of IFR/EVA composites. Many carbon microspheres were observed by SEM which were deposited in the char matrix after the cone calorimeter test. These carbon microspheres had better graphite structure, thus the char was strengthened and could resist more heat and gas flow erosion. The synergistic effect between the gas phase and condensed phase was considered the main factor for the increase of flame retardant properties.
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
·
2021
·Vol. 46
·期 1
·107-116
·
IF 2.407
Santosh Khanal,Yunhua Lu,Dandan Jin,Shiai Xu
Summary In this study, two layered double hydroxides (LDHs), ZnAl-LDH, and MgAl-LDH, were combined with intumescent flame retardant (IFR) consisting of ammonium polyphosphate and tris (2-hydroxyethyl) isocyanurate to prepare flame retardant high density polyethylene composites. The thermal and flame retardant properties of these composites were investigated by thermogravimetric analysis, limiting oxygen index measurement, and cone calorimetry, while the morphology and chemical structure of the char residue were analyzed by scanning electron microscopy, Fourier transfer infrared spectroscopy, and laser Raman spectroscopy. The results showed that the peak heat release rate (PHRR) of both HD/IFR/Zn-LDH and HD/IFR/Mg-LDH composites was 52.0% and 12.0% lower than that of HD and HD/IFR, respectively, suggesting that there was no difference in the reduction of PHRR between the two LDHs. The use of LDHs resulted in the formation of compact char residue with a high graphitic degree, but no significant increase in tensile strength.
研究领域:
材料科学
·
燃烧学
✓ 已验证
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
·
2017
·
IF 2.843
Wei Wang,Xin Wang,Ying Pan,Kim Meow Liew,Ola A. Mohamed,Lei Song,Yuan Hu
Phosphorylated graphene oxides (PGO) were synthesized by a one-pot method and fabricated on the surface of cotton fabrics for the improvement of fire safety. The chemical structure of PGO was characterized by FTIR and XPS. SEM images of the pure and coated cotton fabrics indicated that PGO had better compatibility with water than GO and was more beneficial for self-assembly fabrication than GO. Vertical flame test and cone calorimeter test revealed that flame retardancy of cotton fabrics was obviously improved by PGO based multilayer coating. The plausible flame retardancy mechanism was proposed: PGO with large layered structures could effectively insulate the permeation of oxygen and volatile flammable gases, thereby decreasing the heat release rate; on the other hand, the presence of phosphorus could play an important role in the catalytic charring effect during combustion, which significantly promoted the formation of char residue and then further prevented the permeation of oxygen and pyrolysis products.
研究领域:
材料科学
·
化学
·
纺织工程
·
防火安全
✓ 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
FIRE SAFETY JOURNAL
·
2022
·
IF 3.78
Qinyong Liu,Xingyu Chen,Guiyang Zhu,Xiaoyu Gu,Hongfei Li,Sheng Zhang,Jun Sun,Xiaodong Jin
A novel integrative supramolecular intumescent flame retardant was fabricated by self-assembly of melamine, p -aminobenzene sulfonic acid and phytic acid and was abbreviated as MAP. After chelation with Fe 3+ or Zn 2+ , the resulted products (MAP-Fe and MAP-Zn) were melt-blended with polylactic acid (PLA) to enhance the flame retardancy of PLA. The fire performance was characterized by limiting oxygen index (LOI), UL-94 vertical burning and cone calorimeter tests. The results showed that control PLA was flammable with a low LOI of 20.4%, and it cannot satisfy any UL-94 grade for its severe ignited dripping, whilst the incorporation of 3% MAP-Zn increased the LOI to 29.2％, upgraded the UL-94 rating to V-0, and reduced the peak heat release rate by 18.7%. It was proposed that MAP-Zn mainly promoted the formation of more graphitic carbon in the char residues . In addition, the presence of 3% MAP-Zn slightly reduced the tensile strength of PLA from 64.9 MPa of the control PLA to 60.1 MPa, which met the requirements of most practical applications.
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
危险品化学品经营许可证（带存储）