Improved flame resistance properties of unsaturated polyester resin with TiO2-MXOY solid superacid

Five SO₄²⁻/TiO₂-M_XO_Y solid super acids (SSA: Cu@Ti:SSA, Zr@Ti:SSA, Fe@Ti:SSA, Mn@Ti:SSA, Mo@Ti:SSA) were successfully prepared by sol–gel method, and its chemical structure and element content were characterized by X-ray diffraction (XRD) analysis, Fourier transform infrared spectroscopy (FTIR) and energy dispersive spectroscopy (EDS). Then, a compound flame retardant system containing SSA and ammonium polyphosphate/montmorillonite (AM) were was introduced into an unsaturated polyester resin (UPR) to enhance the flame retardance. The effect of SSA on the flammability and thermal stability of the UPR was evaluated by the limiting oxygen index (LOI), cone calorimeter test (CCT) and thermogravimetric analysis (TGA). The LOI results showed that the flame retardance of the UPR composites was significantly improved with the addition of SSA. Moreover, their heat release rate (HRR), total heat release (THR), the smoke production rate (SPR) and CO and CO₂ yield were much decreased. In addition, the initial decomposition temperature of UPR/AM/SSA was delayed, indicating that their thermal stability was increased, and the residual char of UPR/AM/SSA was also increased due to strong catalytic of SSA ability for esterification and dehydration. Furthermore, the microstructure of the residual char after combustion of the UPR composites was studied by the scanning electron microscopy (SEM), and it was found that the char layer structure was more continuous and dense after the addition of the SSA. In sum up, the synergistic effect between SSA and AM was the main factor for the great improvement of flame retardant of UPR composites.     

磷系阻燃剂FR/APP协效阻燃PP

采用氧指数测定仪、热重分析仪和锥形量热仪研究了磷系阻燃剂1,3,5-三(5,5-二甲基-1,3-二氧杂环己内磷酸基)苯(FR)和聚磷酸铵(APP)复配体系对聚丙烯(PP)材料阻燃性能的影响.结果表明,FR/APP提高了PP的极限氧指数(LOI)、热稳定性和残炭率,降低了热释放速率.当w(FR)为15%和w(APP)为10%复配阻燃PP时,复合材料的LOI为29.6%.阻燃级别达到UL 94 V-0级.     

Macromolecular Nitrogen-Phosphorous Compound/Expandable Graphite Synchronous Expansion Flame Retardant Polystyrene Foam

A macromolecular nitrogen-phosphorous flame retardant combined with expandable graphite (EG) was employed to flame-retard expanded polystyrene foam. As the intumescent char formation (catalyzed by the flame retardant) temperature overlaps with the expanding temperature of EG, their synchronous expansion occurs. In this process, the EG sheets can be embedded in the intumescent char and pushed forward to the surface with inflation of the composite chars, which greatly enhances the compactness and strength of the char layer, and better shields the heat and oxygen, as well as promotes the interactions of the degraded products of the polymer and the flame retardant. The limiting oxygen index (LOI), vertical flame and cone calorimeter tests showed that good flame retardance for the flame retardant EPSF could be achieved (LOI: 33.9%, UL94-V0 (1.6 mm) and remarkably decreased heat release rate). A series of characterizations—including char morphology observation scanning by electron microscope, surface elements determination through X-ray photoelectron spectroscopy, char strength test and thermogravimetric analysis—were performed to verify the synergistic mechanisms based on the synchronous expansion of the composite chars.     

壳聚糖/ZIF⁃67杂化物的制备及其对环氧树脂阻燃抑烟性能的影响

为了提高环氧树脂（EP）的阻燃抑烟性能,采用共沉淀法将类沸石咪唑酯骨架材料ZIF⁃67负载到壳聚糖（CS）表面,通过傅里叶红外光谱（FTIR）、X射线衍射（XRD）和扫描电子显微镜 （SEM）对其结构和形貌进行分析,结果表明杂化物CS⁃ZIF⁃67成功制备。将不同比例的CS⁃ZIF⁃67添加到EP中,研究其对EP阻燃抑烟性能的影响。结果表明,与纯的EP相比,CS⁃ZIF⁃67的加入可以提高EP复合材料的垂直燃烧UL 94等级和极限氧指数（LOI）、降低EP复合材料的热释放速率（HRR）和烟释放速率（SPR）,提高复合材料燃烧后的残炭量,CS⁃ZIF⁃67的加入可以有效提高EP的阻燃抑烟性能。对EP复合材料燃烧后的残炭进行SEM和Laman光谱分析。结果表明,CS⁃ZIF⁃67的加入,使得残炭的石墨化程度提高,EP燃烧时能形成更加致密的炭层,从而起到阻燃抑烟的作用。     

Vinyl polysiloxane microencapsulated ammonium polyphosphate and its application in flame retardant polypropylene

Vinyl polysiloxane microencapsulated ammonium polyphosphate (MAPP) was prepared by a sol-gel method using vinyltrimethoxysilane as a precursor to improve its thermal stability and hydrophobicity. The MAPP was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive spectrometer (EDS) and thermogravimetric analyzer (TGA). The results showed that ammonium polyphosphate (APP) was successfully coated with vinyl polysiloxane. MAPP and pentaerythritol (PER) were used together to improve the flame retardancy of polypropylene (PP). The flame retardant properties of PP composites were investigated by limiting oxygen index (LOI), UL-94 test, TGA and SEM. When the MAPP was added as a flame retardant, with PER as a char forming agent, the LOI of PP/MAPP/PER composites was 33.1%, and it reached the UL-94 V-0 level. The results also demonstrated that the flame retardant properties of PP/MAPP/PER composites were better than those of PP/APP/PER composites at the same loading. Moreover, the addition of flame retardant and carbon forming agent could promote the crystallization behavior of PP.     

Investigation of the influence of red phosphorus,expansible graphite and zinc borate on flame retardancy and wear performance of glass fiber reinforced PA6 composites

The flame retarded materials were prepared which used wear‐resistant PA6 composite (PA6/GF/PTFE/UHMWPE/CG, 85/15/5/5/5 by weight) as matrix, red phosphorus (RP), expansible graphite (EG), and zinc borate (ZB) as fire retardant. The flame retarded properties were characterized by LOI and UL‐94 testing. PA6 composite with 15 wt% RP reached V0 rating and had a high LOI value (27.3 vol%). When a combination of 7 wt% ZB and 8 wt% RP was added, increases in LOI (27.9 vol%) and UL‐94 rating(V0) were both observed. Thermogravimetric analysis (TGA) and char residue characterization showed that the combination of RP and ZB can promote the formation of char barrier, reduce the mass loss rate, and thus improve the flame retardancy of PA6 composites. The wear test showed that, the composite filled by 15 wt% RP or a combination of 7 wt% ZB and 8 wt% RP both possessed a low wear rate and a much stable friction coefficient. The presence of EG could also improve the flame retardance but was harmful to the mechanical property as well as wear performance. The results indicated that ZB and RP had synergy effect on improving both flame retardance and wear performance of PA6 composites. POLYM. COMPOS., 38:2090–2097, 2017. © 2015 Society of Plastics Engineers     

磷化酚醛树脂的合成及其阻燃性能研究

以苯酚,三氯氧磷(POCl3),热塑性酚醛树脂(FR)为原料,三乙胺(Et3N)为缚酸剂合成了一种新型的含磷阻燃剂-磷化酚醛树脂(FR-P),采用红外光谱(FT IR),核磁共振磷谱(31PNMR),电感耦合等离子体发射光谱(ICP)及热重分析(TG)对聚合物的结构及热性能进行了表征,探讨了合成中的各因素对反应的影响,得出了最佳的合成工艺条件,并将合成的化合物用于PC的阻燃,采用热分析法、极限氧指数法(LOI)对阻燃体系的热性能和阻燃性能进行了表征,并与PC/FR阻燃体系进行了比较。研究结果表明,FR-P在高温下的热稳定性和成炭性与FR相比有较大的提高,它能促进PC热降解时成炭,使PC的热分解速率降低,当FR-P添加量为15%时,阻燃体系的LOI达31%,且通过UL94V-1级测试,其阻燃效果远远好于FR。     

PBT/TPU/DOPO-MA阻燃复合材料的制备及性能

通过使用9,10-二氢-9-氧杂-10-磷朵菲-10-氧化物（DOPO）和马来酸酐反应合成制备DOPO衍生物阻燃剂DOPO-MA,并且其结构使用傅里叶红外光谱分析（FTIR）和核磁共振氢谱分析（¹H NMR）技术进行表征。将阻燃剂与聚对苯二甲酸丁二醇酯（PBT）和热塑性聚氨酯（TPU）熔融共混以制备PBT/TPU/DOPO-MA阻燃复合材料。通过运用锥形量热、UL-94、极限氧指数（LOI）、热重分析（TGA）、差热分析（DSC）和力学测试,研究了阻燃剂对复合材料的性能影响。测试结果表明,PBT/TPU/DOPO-MA复合材料具有良好的阻燃性能,加入10％DOPO-MA后,LOI从23.2增加到31.6,可达到UL-94 V-1等级,热释放率峰值（PHRR）和最大成热辐射速率（MAHRE）值降低;热重分析测试结果表明,添加DOPO-MA可以使得阻燃复合材料的热稳定性有显著的提高,当加入10％DOPO-MA后,残炭量可从6.87增加到14.36。此外,随着DOPO-MA含量的增加,阻燃复合材料的结晶度可得到一定的提高。     

Preparation of a chitosan‐based flame‐retardant synergist and its application in flame‐retardant polypropylene

A novel flame‐retardant synergist, chitosan/urea compound based phosphonic acid melamine salt (HUMCS), was synthesized and characterized by Fourier transform infrared spectroscopy and ³¹P‐NMR. Subsequently, HUMCS was added to a fire‐retardant polypropylene (PP) compound containing an intumescent flame‐retardant (IFR) system to improve its flame‐retardant properties. The PP/IFR/HUMCS composites were characterized by limiting oxygen index (LOI) tests, vertical burning tests (UL‐94 tests), microscale combustion calorimetry tests, and thermogravimetric analysis to study the combustion behavior and thermal stability. The addition of 3 wt % HUMCS increased the LOI from 31.4 to 33.0. The addition of HUMCS at a low additive amount reduced the peak heat‐release rate, total heat release, and heat‐release capacity obviously. Furthermore, scanning electron micrographs of char residues revealed that HUMCS could prevent the IFR–PP composites from forming a dense and compact multicell char, which could effectively protect the substrate material from combusting. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40845.     

阻燃大豆蛋白纤维的热性能研究

为了提高阻燃性,用四溴酞酐(TBPA)加有机二酸体系对大豆蛋白纤维进行了阻燃处理,然后用极限氧指数(LOI)、剩炭率表征了它的阻燃性能,用热分析和扫描电子显微镜研究了它的热性能。结果表明:与纯大豆蛋白纤维相比,阻燃处理后的大豆蛋白纤维的极限氧指数和剩炭率提高,热分解起始温度降低,阻燃性能得到了明显改进。     

磷腈/三嗪双基分子复配阻燃聚乳酸

将磷腈/三嗪双基分子阻燃剂（HTTCP）分别与六苯氧基环三磷腈（HPCTP）和季戊四醇磷酸酯（PEPA）按不同配比复配,采用熔融共混法制备了阻燃聚乳酸（PLA）的复合材料。采用热失重分析仪、极限氧指数仪、垂直燃烧试验箱和锥形量热仪研究了2种复配阻燃体系及其配比对PLA阻燃复合材料热稳定性和阻燃性能的影响,并采用扫描电子显微镜对材料的残炭形貌进行了分析,探究了其阻燃机理。结果表明,PEPA/HTTCP复配阻燃剂的阻燃效果优于HPCTP/HTTCP复配阻燃剂。当PEPA/HTTCP的质量比为3/1,总添加量为20 %时,阻燃PLA的极限氧指数最高,为27.2 %,热释放速率峰值、平均热释放速率以及热释放总量达到最小值,且能够达到UL 94 V-0级。     

Effect of a novel phosphorus‐containing compound on the flame retardancy and thermal degradation of intumescent flame retardant polypropylene

A novel flame retardant, tetra(5,5‐dimethyl‐1,3‐ dioxaphosphorinanyl‐2‐oxy) neopentane (DOPNP), was synthesized successfully, and its structure was characterized by FT‐IR, ¹H NMR, and ³¹P NMR. The thermogravimetric analysis (TGA) results demonstrate that DOPNP showed a good char‐forming ability. Its initial decomposition temperature was 236.4°C based on 1% mass loss, and its char residue was 41.2 wt % at 600°C, and 22.9 wt % at 800°C, respectively. The flame retardancy and thermal degradation behavior of novel intumescent flame‐retardant polypropylene (IFR‐PP) composites containing DOPNP were investigated using limiting oxygen index (LOI), UL‐94 test, TGA, cone calorimeter (CONE) test, and scanning electron microscopy (SEM). The results demonstrate that DOPNP effectively raised LOI value of IFR‐PP. When the loading of IFR was 30 wt %, LOI of IFR‐PP reached 31.3%, and it passed UL‐94 V‐0. TGA results show that DOPNP made the thermal decomposition of IFR‐PP take place in advance; reduced the thermal decomposition rate and raised the residual char amount. CONE results show that DOPNP could effectively decrease the heat release rate peak of IFR‐PP. A continuous and compact char layer observed from the SEM further proved the flame retardance. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011.     

AlPi和PPBBA复配阻燃PET的燃烧性能

采用二乙基次膦酸铝(Al Pi)和聚丙烯酸五溴卞酯(PPBBA)复配,提高聚对苯二甲酸乙二酯(PET)的阻燃性能。测定了阻燃PET的极限氧指数(LOI)、垂直燃烧性能、热失重分析、动态流变性能,并采用扫描电子显微镜(SEM)观测了燃烧炭层的形貌。结果表明,Al Pi∶PPBBA分别以5∶5和10∶5复配,添加量分别为10%和15%时,LOI达到28.0%和33.3%,垂直燃烧测试均达到V–0级。复配阻燃体系的加入促进了PET的提前分解,阻燃剂主要在气相发挥阻燃作用,同时有利于成炭。当添加15%复配阻燃剂时,相比于纯PET,阻燃PET的最大分解速率降低21.2%,残炭率提高97.6%,提高了阻燃PET在高温下的热稳定性。在角频率为1 rad/s条件下,当添加10%和15%复配阻燃剂时,体系的复数黏度由39.4 Pa·s分别提高到296 Pa·s和1 970 Pa·s,具有较高的抗熔滴性能。烧结后的残留物高倍膨胀,炭层致密连续。     

Influence of the pentaerythritol phosphate melamine salt content on the combustion and thermal decomposition process of intumescent flame‐retardant ethylene–vinyl acetate copolymer composites

Pentaerythritol phosphate melamine salt (PPMS) as a single‐molecule intumescent fire retardant was synthesized and characterized. The influence of the PPMS content on the combustion and thermal decomposition processes of intumescent‐flame‐retardant (IFR) ethylene–vinyl acetate copolymer (EVA) composites was studied by limiting oxygen index (LOI) measurement, UL 94 rating testing, cone calorimetry, thermogravimetric analysis, and scanning electron microscopy. The LOI and UL 94 rating results illustrate that PPMS used in EVA improved the flame retardancy of the EVA composites. The cone calorimetry test results show that the addition of PPMS significantly decreased the heat‐release rate, total heat release, and smoke‐production rate and enhanced the residual char fire performance of the EVA composites. The IFR–EVA3 composite showed the lowest heat‐release and smoke‐production rates and the highest char residue; this means that the IFR–EVA3 composite had the best flame retardancy. The thermogravimetry results show that the IFR–EVA composites had more residual char than pure EVA; the char residue yield increased with increasing PPMS content. The analysis results for the char residue structures also illustrated that the addition of PPMS into the EVA resin helped to enhance the fire properties of the char layer and improve the flame retardancy of the EVA composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 42148.     

ZnO对PP/MPP/PEPA膨胀阻燃体系的协同作用

以ZnO为阻燃协效剂,采用多聚磷酸蜜胺(MPP)和笼状季戊四醇磷酸酯(PEPA)复配阻燃剂,制备了具有良好阻燃性能的无卤阻燃PP。研究了ZnO用量对PP阻燃性能和协效作用的影响。结果表明:添加少量的ZnO即可显著提高PP的阻燃性能。当MPP、PEPA和ZnO添加量分别为12%、8%和1%时,阻燃PP的氧指数高达29.5%。TGA、FTIR分析和体式显微镜观测结果表明:添加ZnO可以催化MPP/PEPA间的酯化反应,促进体系成炭,形成更致密的炭层,从而提高材料的阻燃性能。     

MPP无卤阻燃聚丙烯纤维的辐照改性研究

采用自制季戊四醇螺环磷酸酯双蜜胺盐(MPP)无卤阻燃剂与聚丙烯(PP)进行共混纺丝,制备了无卤阻燃PP纤维,采用低能电子辐照对无卤阻燃PP纤维进行改性,并对MPP的结构、PP纤维的力学性能及阻燃性能进行了表征。结果表明:自制MPP为预期结构;随着MPP含量的增加,PP纤维的极限氧指数(LOI)增大,但其断裂强度有所下降;MPP质量分数为8%时,纤维断裂强度为6.02 cN/dtex,LOI为24.5%;随低能电子辐照量的增大,MPP质量分数8%的阻燃PP纤维的LOI大幅度增加;当电子辐照量为200 kGy时,阻燃PP纤维的LOI为33.8%,断裂强度为3.08 cN/dtex,起始分解温度和残炭率比纯PP纤维均有较大幅度增加,燃烧形成连续致密的炭层。     

A novel bio-based charcoal-forming agent based on chitosan and phytate@Mg to improve the flame retardancy of poly(lactic acid)

A novel bio-based carbon forming agent (Mg@PA-CS) containing P and N elements was were synthesized using the complexation characteristics of chitosan (CS) and phytate (PA). The flame retardant behavior of poly(lactic acid) (PLA)/Mg@PA-CS/APP composites (addition of 20 wt% of different ratios of Mg@PA-CS and APP to polylactic acid composites) were investigated by the limiting oxygen index (LOI), vertical burning test (UL-94), cone calorimetry test (CCT), and thermogravimetric analysis (TGA). Due to the biphasic flame retardant and synergistic effect, since the 20 wt% flame retardant system (Mg@PA-CS:APP = 1:2), PLA composites passed the UL-94 test V-0 rating, reached 34% LOI value. The peak heat release rate (PHRR) and total heat release rate (THR) were reduced to 1/2 of the pure PLA, char residue could be as high as 11.49% at 800°C. Moreover, the flame-retardant mechanism of PLA composites during thermal decomposition was analyzed using a scanning electron microscope (SEM) and the coupling techniques of TGA linked with FT-IR (TG-FTIR).     

自制高效无卤含磷阻燃剂阻燃环氧树脂研究

采用自制的阻燃剂双｛4-［4-（4-氨基苄基）苯氨基］ ［（6-氧二苯并［c,e］［1,2］氧磷菲?6?基）甲基］苯基｝苯基膦酸酯（DOP-DDM）,以及DOP?DDM与金属氧化物复合,分别用于制备高效阻燃环氧树脂（EPM）。通过极限氧指数（LOI）、垂直燃烧（UL 94）和锥形量热燃烧试验评价了阻燃性能,利用热失重分析和动态热机械分析研究了热性能,热失重与红外光谱仪联用、扫描电子显微和拉曼光谱分析了阻燃机理。结果表明,DOP-DDM的引入会降低阻燃EPM的起始降解温度,但不会影响其玻璃化转变温度,提高了残炭率、储能模量、损耗模量和阻燃性能;DOP?DDM添加量为4.7 %（质量分数,下同）,磷含量仅0.37 %,阻燃EPM的LOI 值为33.5 %,UL 94达V-0 级,热释放速率峰值、总热释放量和总烟释放量分别降低了23.2 %、17.8 %和12.4 %;3.7 %的DOP-DDM与1.0 %的Al₂O₃复合,阻燃EPM达UL 94 V-0级,不仅热释放速率峰值和总烟释放量进一步降低,而且CO和CO₂毒气分别降低了7.7 %和17.2 %。     

The effect of different organic modified montmorillonites (OMMTs) on the thermal properties and flammability of PLA/MCAPP/lignin systems

The effect of different organic modified montmorillonites (DK1, DK2, and DK4) based on a novel intumescent flame retardant (IFR) poly(lactic acid) (PLA) system is reported. The IFR system was composed of microencapsulated ammonium polyphosphate and lignin. The morphological characterization of PLA/OMMT nanocomposites was conducted by X‐ray diffractometry and transmission electron microscopy. The flame retardant and thermal properties of the composites were evaluated by limiting oxygen index (LOI), vertical burning test (UL‐94), and cone calorimeter. From the results, it could be seen that the sample containing DK2 possessed the best flame retardance, such as lower peak heat release rate (pHRR) and higher LOI value. The thermal degradation and gas products of the samples were monitored by thermogravimetric analysis and thermogravimetric analysis infrared spectrometry. Scanning electron microscopy was used to explore the surface morphology of the char residues. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2013     

Flame‐retardant ABS resins from novel phenyl isocyanate blocked novolac phenols and triphenyl phosphate

In an effort to prepare a novel novolac phenol (NP) based char former with good solubility, the hydroxyl functionalities of NP were blocked with phenyl isocyanate (PI) via a simple urethane‐forming reaction. The chemical structure and properties of the obtained novolac phenol–phenyl isocyanate adduct (NP–PI) were characterized with gel permeation chromatography, Fourier transform infrared spectroscopy, ¹H‐NMR, and differential scanning calorimetry. Adducts of two kinds of NPs (molecular weights = 450 and 800) with PI were used as potential char formers for this study. Thus, a two‐component system using NP–PI as a char former and triphenyl phosphate (TPP) as a phosphorous‐based flame retardant was blended with ABS, and the thermal degradation behavior and flame retardance were examined as a function of the molar mass of NP–PI and the TPP/NP–PI ratio with thermogravimetric analysis and limiting oxygen index (LOI) testing. ABS compositions with no NP–PI were also prepared for comparison. The mixtures showed a synergistic effect between TPP and NP–PI on the flame‐retardance enhancement of ABS. Those containing the higher molar mass NP–PI adduct were the most flame retardant, and a LOI value as high as 41 was obtained. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 102: 721–728, 2006