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Preparation of Poly(phosphoric acid piperazine) and Its Application as an Effective flame Retardant for Epoxy Resin

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Chinese Journal of Polymer Science 2018年第5期36卷 655-664页

作者： Miao-Jun Xu Si-Yu Xia Chuan Liu Bin Li Heilongjiang Key laboratory of Molecular Design and Preparation of flame retarded materials College of Science Northeast Forestry University

A phosphorus-nitrogen containing flame retardant additive of poly（phosphoric acid piperazine）, defined as PPAP, was synthesized by the salt-forming reaction between anhydrous piperazine and phosphoric acid, and the dehydration polymerization under heating in nitrogen atmosphere. Its chemical structure was well characterized by Fourier transform infrared（FTIR） spectroscopy, ^（13）C and ^（31）P solid-state nuclear magnetic resonance measurements. The synthesized PPAP and curing agent m-phenylenediamine were blended into epoxy resin（EP） to prepare flame retardant EP thermosets. The effects of PPAP on the fire retardancy and thermal degradation behavior of cured EP/PPAP composites were investigated by limiting oxygen index（LOI）, vertical burning（UL-94）, thermogravimetric analysis/infrared spectrometry（TG-IR） and cone calorimeter tests. The morphologies and chemical compositions of char residues for cured epoxy resin were investigated by scanning electron microscopy（SEM） and X-ray photoelectron spectroscopy（XPS）, respectively. The results demonstrated that the flame retardant EP thermosets successfully passed UL-94 V-0 flammability rating and the LOI value was as high as 30.8% when incorporating 5 wt% PPAP into the EP thermosets. The TGA results indicated that the synthesized PPAP flame retardant additive possessed high thermal stability and excellent charring capability. Meanwhile, the incorporation of PPAP stimulated the epoxy resin matrix to decompose and charring ahead of time due to its catalytic decomposition effect, which led to a higher char yield at high temperature. The morphological structures and the analysis results of XPS for char residues of EP thermosets revealed that the introduction of PPAP benefited the formation of a sufficient, more compact and homogeneous char layer containing phosphorus-nitrogen flame retardant elements on the material surface during combustion. The formed char layer with high quality effectively prevented the heat transmission and d

关键词： Synthesis Poly(phosphoric acid piperazine) flame retardant Epoxy resin thermosets Thermal degradation

Unleashing the Power of Bio-based Thermotropic Liquid Crystal Modifiers:Toughening and Reinforcing Petroleum-based Epoxy Resin without Compromising Other Properties

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Chinese Journal of Polymer Science 2024年第8期42卷 1093-1102页

作者： Qing-Yun Lu Hong-Wei Gu Jia-Hui Li Qian-Qian Fan Bei-Tao Liu Yan Kou Xi-Gao Jian Zhi-Huan Weng State Key laboratory of Fine Chemicals Frontiers Science Center for Smart MaterialsLiaoning Technology Innovation Center of High Performance Resin MaterialsDepartment of Polymer Science&EngineeringDalian University of TechnologyDalian 116024China Thermochemistry laboratory Liaoning Province Key Laboratory of Thermochemistry for Energy and MaterialsDalian National Laboratory for Clean EnergyDalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China

Toughening the petroleum-based epoxy resin blends with bio-based modifiers without compromising their modulus,mechanical strength,and other properties is still a big challenge in view of the *** this study,a bio-based liquid crystal epoxy resin(THMT-E P)with an s-triazine ring structure was utilized to modify a petroleum-based bisphenol A epoxy resin(E51)with 4,4'-diaminodiphenylsulfone(DDS)as a curing agent,and the blended systems were evaluated for their thermal stability,mechanical properties,and flame *** results showed that the impact strength of the blended system initially increased and then decreased with the increase in THMT-EP content,and it reached the a maximum value of 26.5 kJ/m^(2)when the THMT-EP content was 5%,which was 31.2%higher than that of E51/***,the flexural strength,modulus,and glass transition tem perature of the blended system were all simultaneously improved with the addition of *** the same time,the addition of THMT-EP enhanced the flame retardancy of the system by increasing the char yield at 700℃and decreasing the peak heat release rate and total heat release *** work paves the way for a more sustainable improvement in the comprehensive performance of epoxy resin.

关键词： Epoxy resin Toughening Bio-based Thermotropic liquid crystal

Ten-Minute Synthesis of a New Redox-Active Aqueous Binder for flame-Retardant Li-S Batteries

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Energy & Environmental materials 2024年第2期7卷 48-57页

作者： Tianpeng Zhang Borui Li Zihui Song Wanyuan Jiang Siyang Liu Runyue Mao Xigao Jian Fangyuan Hu School of materials Science and Engineering State Key Laboratory of Fine ChemicalsFrontiers Science Center for Smart Materials Oriented Chemical Engineering Technology Innovation Center of High Performance Resin Materials(Liaoning Province)Key Laboratory of Energy Materials and Devices(Liaoning Province)Dalian University of TechnologyDalian 116024China State Key laboratory of Fine Chemicals Frontiers Science Center for Smart Materials Oriented Chemical EngineeringSchool of Chemical Engineering Technology Innovation Center of High Performance Resin Materials(Liaoning Province)Key Laboratory of Energy Materials and Devices(Liaoning Province)Dalian University of TechnologyDalian 116024China

As a critical role in battery systems,polymer binders have been shown to efficiently suppress the lithium polysulfide shuttling and accommodate volume changes in recent ***,preparation processes and safety,as the key criterions for Li-S batteries'practical applications,still attract less ***,an aqueous multifunction binder(named PEI-TIC)is prepared via an easy and fast epoxy-amine ring-opening reaction(10 min),which can not only give the sulfur cathode a stable mechanical property,a strong chemical adsorption and catalytic conversion ability,but also a fire safety *** Li-S batteries based on the PEI-TIC binder display a high discharge capacity(1297.8 mAh g^(-1)),superior rate performance(823.0 mAh g^(-1)at 2 C),and an ultralow capacity decay rate of 0.035%over more than 800 *** under 7.1 mg cm^(-2)S-loaded,the PEI-TIC electrode can also achieve a high areal capacity of 7.2 mA h g^(-1)and excellent cycling stability,confirming its application ***,it is also noted that TG-FTIR test is performed for the first time to explore the flame-retardant mechanism of polymer *** work provides an economically and environmentally friendly binder for the practical application and inspires the exploration of the flame-retardant mechanism of all electrode components.

关键词： 3D cross-linked network environmentally friendly flame retardant Li-S batteries multifunction binder

Synthesis,thermal property and hydrolytic degradation of a novel star-shaped hexa[p-(carbonylglycinomethylester)phenoxy]cyclotriphosphazene

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Science China Chemistry 2009年第12期52卷 2186-2194页

作者： BING BaiChun LI Bin Heilongjiang Key laboratory of Molecular Design and Preparation of flame retarded materials College of ScienceNortheast Forestry UniversityHarbin 150040China

A novel star-shaped cyclotriphosphazene substituted by glycinomethylesterphenoxy and its intermediates are synthesized from hexachlorocyclotriphosphazene (HCCP). The structures are characterized by 1H NMR, 13C NMR, 31P NMR, FTIR and elemental analysis. Their thermal properties are clarified by thermogravimetric analysis (TGA), differential scanning calorimentry (DSC) and FTIR, while hydrolytic degradation behaviour is studied with UV-vis spectrophotometer and by measuring the weight loss, and the phosphorus content of residue. According to hydrolysis behaviour of hexa[p-(carbonylglycinomethylester)phenoxy]cyclotriphosphazene (HGPCP) under different conditions, it is easy to hydrolyze in hydrochloric acid (pH 1.0) than in phosphate buffer (pH 7.4) at 37°C. And the sample hydrolytic degradation still remains at the stage of side groups’ break. The TGA data show that the thermal stability of the hexa[p-(aldehyde)phenoxy]cyclotriphosphazene (HAPCP), hexa[p-(carboxyl) phenoxy]cyclotriphosphazene (HCPCP) and HGPCP is so high that their char residues are 75%, 47% and 47% at 800°C, respectively, probably due to cross-linking between molecules.

关键词： phosphazene glycino methyl ester synthesis hydrolytic degradation thermal properties

Synthesis and Structure of A Novel Caged Bicyclic Phosphate flame Retardant

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Chinese Chemical Letters 2000年第10期11卷 887-890页

作者： Li, X Ou, YX Zhang, YH Lian, DJ Beijing Inst Technol Natl Lab Flame Retarded Mat Beijing 100081 Peoples R China

PI novel caged bicyclic phosphate flame retardant tri(1-oxo-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane-methyl) phosphate (Trimer) was synthesized from 1-oxo-4-hydroxymethyl-2,6,7-trioxa-1-phosphabicyclo [2.2.2] octane (PEPA) and phosphorus oxychloride in this paper. Its structure was characterized by elemental analysis. FTIR, H-1 NMR. P-31 NMR and X-ray diffraction analysis.

关键词： caged bicyclic phosphate flame retardant crystal structure

Toughened (Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)–SiC composites fabricated by one-step reactive sintering with a unique SiB_(6) additive

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Journal of Advanced Ceramics 2024年第1期13卷 86-100页

作者： Wei Hao Xinzhe Lu Ling Li Tao Wang Guoliang Ren Huangyue Cai Xiaofeng Zhao Dongyun Wang Na Ni Zhejiang Provincial Key laboratory of Urban Rail Transit Intelligent Operation and Maintenance Technology&Equipment Zhejiang Normal UniversityZhejiang 321004China Key lab of Education Ministry for Power Machinery and Engineering School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China School of materials Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China

High-entropy diboride has been arousing considerable interest in recent ***,the low toughness and damage tolerance limit its applications as ultra-high-temperature structural *** we report that a unique SiB_(6) additive has been first incorporated as boron and silicon sources to fabricate a high-entropy boride(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)–SiC composite though one-step boro/carbothermal reduction reactive sintering.A synergetic effect of high-entropy sluggish diffusion and SiC secondary phase retarded the grain growth of the(Ti_(0.2)Zr_(0.2)Hf_(0.2)Nb_(0.2)Ta_(0.2))B_(2)–51SiC *** small grain size was beneficial to shorten the diffusion path for mass transport,thereby enhancing the relative density to~99.3%.These results in an increase of fracture toughness from~5.2 in HEBS-1900 to~7.7 MPa·m^(1/2) in HEBS-2000,which corresponded to a large improvement of 48%.The improvement was attributed to a mixed mode of intergranular and transgranular cracking for offering effective pinning in crack propagation,resulting from balanced grain boundary strength collectively affected by improved densification,solid solution strengthening,and incorporation of SiC secondary phase.

关键词： high-entropy diboride silicon hexaboride boro/carbothermal reduction reactive sintering fracture toughness

flame Retardant and Pyrolytic Behaviors of Polyamide 6/Montmorillonite Nanocomposite

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Defence Technology（防务技术） 2005年第2期1卷 162-168页

作者：刘治国欧育湘吴俊浩 national lab of flame-retarded materials Beijing Institute of Technology Beijing 100081 China School of Chemistry and Chemical Engineering Henan University Kaifeng 475001 Henan China national lab of flame-retarded materials Beijing Institute of Technology Beijing 100081 China Institute of Organic Chemistry Chinese Academy of Sciences Shanghai 200032 China

Na +-montmorillonite(Na +-MMT) was converted to organic montmorillonite(OMMT) using modifier which was synthesized at authors’ laboratory. PA6/OMMT nanocomposite was prepared via in situ intercalative polymerization. The limiting oxygen index (LOI), UL 94V flame retardancy and thermal stability of PA6/OMMT using thermal gravity analysis (TGA) were measured. The Fourier transform infrared (FTIR) technique was used to analyze the pyrolytic residuum and the cone calorimeter (CONE) was applied to determine a number of combustion parameters which were closely related to fire safety, including heat release rate, mass loss rate, effective combustion heat, total heat release, specific extinction area and the time of ignition. In addition, the elemental composition of the surface pyrolytic residuum and the corresponding X-ray photoelectron spectroscopy (XPS) data were obtained, and the morphology of the residuum from CONE measurement was examined by scanning electron microscope (SEM).

关键词： polyamide 6 montmorillonite nanocomposite in situ intercalative polymerization flame retardancy pyrolysis

Carbon Fibers Decorated by Polyelectrolyte Complexes toward Their Epoxy Resin Composites with High Fire Safety

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Chinese Journal of Polymer Science 2018年第12期36卷 1375-1384页

作者： Xiao-Hui Shi Li Chen Bo-Wen Liu Jia-Wei Long Ying-Jun Xu Yu-Zhong Wang School of Chemical Engineering National Engineering Laboratory of Eco-Friendly Polymeric Materials (Sichuan) State Key Laboratory of Polymer Materials Engineering Sichuan University Chengdu 610064 China

The achievement of both robust fire-safety and mechanical properties is of vital requirement for carbon fiber （CF） composites. To this end, a facile interracial strategy for fabricating flame-retardant carbon fibers decorated by bio-based polyelectrolyte complexes （PEC） consisting of chitosan （CH） and ammonium polyphosphate （APP） was developed, and its corresponding fire-retarded epoxy resin composites （EP/（PEC@CF）） without any other additional flame retardants were prepared. The decorated CFs were characterized by SEM- EDX, XPS and XRD, indicating that the flame-retardant PEC coating was successfully constructed on the surface of CF. Thanks to the nitrogen- and phosphorous-containing PEC, the resulting composites exhibited excellent flame retardancy as the limiting oxygen index （LOI） increased from 31.0% of EP/CF to 40.5% and UL-94 V-0 rating was achieved with only 8.1 wt% PEC. EP/（PEC8.1@CF） also performed well in cone calorimetry with the decrease of peak-heat release rate （PHRR） and smoke production rate （SPR） by 50.0% and 30.4%, respectively, and the value of fire growth rate （FIGRA） was also reduced to 3.41 kW·m-2- s-1 from 4.84 kW· m-2· s-1, suggesting a considerably enhanced fire safety. Furthermore, SEM images of the burning residues revealed that the PEC coating exhibited the dominant flame-retardant activity in condensed phase via the formation of compact phosphorus-rich char. In addition, the impact strength of the composite was improved, together with no obvious deterioration of flexural properties and glass transition temperature. Taking advantage of the features, the PEC-decorated carbon fibers and the relevant composites fabricated by the cost-effective and facile strategy would bring more chances for widespread applications.

关键词： Fire safety Carbon fiber composites Epoxy resin Polyelectrolyte complexes

flame Retardancy, Smoke Suppression Effect and Mechanism of Aryl Phosphates in Combination with Magnesium Hydroxide in Polyamide 6

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Journal of Wuhan University of Technology(materials Science) 2012年第5期27卷 916-923页

作者：陈俊刘述梅 College of materials Science and Engineering South China University of Technology The Key lab of GDfor High Property and Functional Macromolecular materials South China University of Technology

The flammability, smoke emission behavior and mechanical properties of two oligomeric aryl phosphates [bisphenol A bis（diphenyl phosphate）（BDP） and resorcinol bis（diphenyl phosphate）（RDP）] combined with magnesium hydroxide （MH） in polyamide 6 （PA6） have been investigated. Combining 5 wt% BDP, 50 wt% MH imparts a limiting oxygen index （LOI） of 40.9% and UL94 V-0 rating to PA6, meanwhile the peak rate of smoke release （pRSR）, total release of smoke （TSR） and Izod notched impact strength are 41%, 33% and 233% relative to the corresponding value of 55 wt% MH without BDP, respectively. Dynamic mechanical analysis （DMA） indicates that the improvement of toughness attributes to the enhanced compatibility between MH and PA6 by adding BDP. Furthermore, based on the comprehensive analysis of thermogravimetry （TG）, cone calorimeter and SEM-EDX investigations, possible flame retardancy and smoke suppression mechanisms were revealed. Besides the fuel dilution and barrier effect of MH, the combination of MH and RDP shows an additional flame inhibition effect. The combination of MH and BDP results in a dominant condensed phase barrier effect which leads to obvious reduction on smoke emission and flammability.

关键词： flame retardancy smoke suppression oligomeric aryl phosphate magnesium hydroxide polyamide 6