阻燃抑烟PVC-U配方的研究

介绍了PVC热降解、燃烧成烟及抑烟的机制,分析了Al(OH)3、钼酸铵/Al(OH)3、硼酸锌/氧化锑对阻燃抑烟性能和力学性能的影响,结果表明:加入15份Al(OH)3即可使PVC-U垂直燃烧性达到FV-0级,再增加其用量,垂直燃烧性没有提高;当m(钼酸铵)∶m[Al(OH)3]=30∶70时,最大烟密度、烟密度等级和氧指数最好;m(硼酸锌)∶m(氧化锑)=50∶50时,其阻燃抑烟效果最好。     

硬质聚氨酯泡沫/聚磷酸铵复合材料的制备及阻燃性能研究

以聚磷酸铵(APP)为阻燃剂,采用一步法全水发泡制备一系列硬质聚氨酯泡沫/聚磷酸铵复合材料(RPUF/APP),通过扫描电镜(SEM)、热重分析(TG)、极限氧指数(LOI)、UL94垂直燃烧以及烟密度测试来研究聚磷酸铵对硬质聚氨酯泡沫(RPUF)泡孔结构、热稳定性、阻燃性能以及燃烧烟密度的影响。研究表明,聚磷酸铵可以明显提高RPUF/APP复合材料的阻燃性能,30份的聚磷酸铵使得RPUF/APP达到UL94 V-0级别,LOI达到23. 6%。同时发现,APP的加入会降低RPUF/APP泡沫复合材料的热分解温度,提高其成炭率和炭层的高温稳定性,并降低复合材料的燃烧烟密度,有效提高复合材料火灾安全性能。     

装饰用木粉/聚氯乙烯木塑复合材料阻燃抑烟的研究

研究了八钼酸铵以及八钼酸铵与其他阻燃剂复合对木粉/聚氯乙烯木塑复合材料阻燃抑烟性能的影响。结果表明:单独添加八钼酸铵、或者八钼酸铵与其他阻燃剂复合,都可以提高木粉/聚氯乙烯木塑复合材料的阻燃性能;其中添加了水滑石和氢氧化镁复合体系明显降低了热释放速率和烟释放速率,热释放速率降低了27%,烟释放速率降低了60%,显示出更好的抑烟效果。通过烟密度测试验证了1#配方复合体系的抑烟性能,烟密度等级由87降到68。     

MoO3/ZnO/APP对硬质PVC抑烟阻燃性能的影响

通过均匀实验设计方法研究了MoO3/ZnO/APP（聚磷酸铵）三元复合抑烟阻燃体系对硬质PVC复合材料的抑烟阻燃性能、力学性能和热稳定性的影响,用SPSS软件对试验结果进行了回归分析。结果表明,当MoO3、ZnO、APP分别为2.5份、3.5份和9份时,复合材料的协同抑烟阻燃性能最好,最大烟密度（SMD）由100降低到77.5,烟密度等级（SDR）由85.3降低到57.4,极限氧指数由44.5%提高到65.0%。复合材料的力学性能略有下降,拉伸强度由36.3MPa降至33.7MPa,断裂伸长率由48.1%降至44.7%。热重分析表明,MoO3/ZnO/APP三元复合抑烟阻燃体系使硬PVC失重温度范围变窄,最大失重温度降低了近50℃,而失重速率明显降低。     

无机填料填充PE-LD/EVA合金的导热及阻燃性能

采用氧化铝（Al2O3）为导热填料、氢氧化镁［Mg(OH)2］为阻燃填料,以低密度聚乙烯（PE-LD）和乙烯醋酸乙烯共聚物（EVA）为基体树脂制备导热阻燃复合材料。通过导热性能测试、燃烧行为表征（极限氧指数和垂直燃烧测试）以及热重分析研究了PE LD/EVA/Al2O3/Mg(OH)2复合材料的导热性能、阻燃性能及热稳定性。结果表明,含有50份Al2O3及50份Mg(OH)2的复合材料,在PE-LD/EVA质量比为1/1时,热导率可达到1.21 W/m·K;材料的阻燃性能及热稳定性都随 EVA 含量的增加而增大,极限氧指数从27.0 % 提高到31.5 %,UL 94 垂直燃烧从无等级提高到V-0级,残炭率从46.5 %提高到57.7 %。     

无卤阻燃抑烟ABS材料的制备及性能研究

采用熔融共混法,以二乙基次膦酸铝（ADP）为主阻燃剂,聚磷酸铵（APP）为协效阻燃剂,对丙烯腈?丁二烯?苯乙烯共聚物（ABS）实现了良好的阻燃抑烟改性。利用极限氧指数测定仪、烟密度测试箱和锥形量热测试仪对复合材料的燃烧性能进行了测试,通过扫描电子显微镜、差示扫描量热仪等分析表征了复合材料的微观结构和热性能。结果表明,当ABS/ADP/APP质量比为100∶16∶4时,复合材料的极限氧指数（LOI）可提高到29 %,烟密度等级下降到68.5,火点指数（FPI值）提高到0.215 s/（kW·m^-2）;复合材料在燃烧过程中会分解产生磷氧自由基,抑制基体燃烧的链式反应,并在材料表面形成大量细小空穴、膨胀疏松的炭层,取得了气相阻燃和凝聚相阻燃之间的良好协效。     

凹凸棒土增强EVA/NBR阻燃复合材料的性能研究

以氢氧化镁（MH）和红磷（RP）为阻燃剂（FR）制备了乙烯醋酸乙烯共聚物/丁腈橡胶(EVA/NBR)阻燃复合材料,并将凹凸棒土（AT）引入到EVA/NBR阻燃复合材料中,以提高其力学性能、耐油性、燃烧性能及热稳定性。结果表明,含有10 份（质量份,下同）AT的阻燃复合材料,其拉伸强度为10.4 MPa,断裂伸长率为627.1 %;浸油后拉伸强度变化率从-29.3 %降低到-13.2 %,断裂伸长率变化率从-25.2 %降低到-8.6 %,且质量增大变化率从10.7 %降低到3.4 %;极限氧指数达到了32.2 %,UL 94垂直燃烧从无等级提高到V 0级;700 ℃时残炭量从29.3 %提高到35.6 %;浸油前后断面观察发现,加入AT后阻燃复合材料的断面更加致密。     

MPP阻燃硬质聚氨酯泡沫制备工艺

通过全水发泡技术制备硬质聚氨酯泡沫/三聚氰胺聚磷酸盐(RPUF/MPP)复合材料，并对其泡孔形貌、热稳定性、阻燃性能、烟释放特性进行研究，结果表明，RPUF/MPP复合材料初始分解温度与纯样相比，升高了18～26℃,热稳定性明显提升；50份MPP使复合材料极限氧指数达到24.4%,垂直燃烧达到UL 94 V-0级。RPUF/MPP50热释放速率峰值和总热释放仅为139 W/g和16.7 kJ/g,与纯样相比，分别降低了32.5%和28.3%。经过MPP改性，RPUF/MPP50最大烟密度及烟密度等级分别降低至32.10%和19.56。炭渣分析表明，MPP可以有效促进RPUF/MPP复合材料燃烧过程中致密炭层的形成，且炭层中石墨化成分比例明显提高，有利于其阻燃性能的提升。研究表明，MPP可以显著提升硬质聚氨酯泡沫火灾安全性能。     

磷酸硼协效膨胀型阻燃剂对聚丙烯阻燃性能的研究

在膨胀型阻燃剂（IFR）中添加不同比例的协效剂磷酸硼（BP）制备复合阻燃剂,将复合阻燃剂加入聚丙烯（PP）中,制备阻燃PP复合材料。通过垂直燃烧、极限氧指数测试、锥形量热测试、热重分析和力学性能测试对PP复合材料进行表征。结果表明：BP对IFR具有显著的协同阻燃效果。当添加2%BP和13%IFR时,PP/IFR/BP复合材料（样品4#）阻燃性能最佳,燃烧等级达到V-0,极限氧指数达到30.8%。样品4#的热释放速率峰值、平均热释放速率、总产烟量和总释放热与加入15%IFR的阻燃PP相比,分别降低19.51%、4.40%、34.00%和6.87%,700℃时样品4#的质量保留率增加50%。燃烧过程中,PP/IFR/BP复合材料的硼元素在凝聚相中催化IFR交联成炭,较未添加BP的复合材料,PP/IFR/BP炭层膨胀程度更高且更致密。BP协效剂的添加降低了阻燃剂的添加量,明显提升复合材料的力学性能。     

化学交联EVA/NBR阻燃复合材料的燃烧行为及力学性能

以乙烯-醋酸乙烯共聚物（EVA）/丁腈橡胶（NBR）为主体,氢氧化镁[Mg(OH)2）]和红磷（RP）为阻燃剂制备了无卤阻燃EVA/NBR复合材料,通过力学性能测试、热重分析以及燃烧行为表征（极限氧指数和锥形量热分析）研究了交联剂过氧化二异丙苯（DCP）以及马来酸酐接枝乙烯-醋酸乙烯共聚物（EVA-g-MAH）对EVA/NBR复合材料的力学性能、热稳定性和阻燃性能的影响。结果表明,含有10份相容剂EVA-g-MAH的交联材料,其拉伸强度可达到17.4 MPa,断裂伸长率可达到1236 %;材料的热分解温度从321.6 ℃提高到327.0 ℃,残炭量从10 %提高到了32.1 %;极限氧指数达到33.5 %且热释放速率峰值从941 kW/m2降到了690 kW/m2;通过扫描电子显微镜对复合材料的断面形貌进行了观察分析,发现材料断裂表面填料分散均匀。     

Synergistic flame retardant effects of ammonium polyphosphate in ethylene‐vinyl acetate/layered double hydroxides composites

Mg–Al–Fe ternary layered double hydroxides (LDH) were synthesized based on bayer red mud by calcination‐rehydration method, and characterized using X‐ray diffraction and thermogravimetric analysis (TGA). The synergistic flame retardant effects of ammonium polyphosphate (APP) with LDH in ethylene‐vinyl acetate (EVA) composites were studied using limiting oxygen index (LOI), UL 94 test, cone calorimeter test (CCT), and smoke density test (SDT). The thermal degradation behavior of EVA/LDH/APP composites was examined by thermal gravimetric analysis‐fourier transform infrared spectrometry (TG‐FTIR). The results showed that LOI values decreased by incorporation of APP together with LDH; and, a suitable amount of APP in EVA/LDH composites can apparently improve UL 94 rating. The CCT results indicated that heat release rate (HRR) of the EVA/LDH/APP composites with APP decreased in comparison with that of the EVA/LDH composites. The SDT results showed that APP was helpful to suppress smoke. The TG‐FTIR data showed that the composites with APP had a higher thermal stability than the EVA/LDH composites at high temperature. POLYM. ENG. SCI., 54:766–776, 2014. © 2013 Society of Plastics Engineers     

Influence of red phosphorus on the flame-retardant properties of ethylene vinyl acetate/layered double hydroxides composites

Mg?CAl?CFe ternary layered double hydroxides (LDHs) were synthesized based on Bayer red mud by a calcination?Crehydration method, and characterized using powder X-ray diffraction and thermogravimetric analysis techniques. The synergistic flame-retardant effects of red phosphorus (RP) in ethylene vinyl acetate (EVA)/LDHs composites were studied with the limiting oxygen index (LOI), the UL 94 test, the cone calorimeter test (CCT), and the smoke density test (SDT). And, the thermal degradation behavior of the composites was examined by thermogravimetry-Fourier transform infrared spectrometry (TG-FTIR) analysis. Results showed that the LOI values of the composites with RP were basically higher than those of the pure EVA sample and composites containing LDHs only. And the addition of a suitable amount of RP in EVA/LDHs/RP composites can apparently favor UL 94 test. In the UL 94 test there was a V-1 rating and dripping phenomena for the composites containing 50?% LDHs. However, the composites containing 47.5?% LDHs and 2.5?% red phosphorus did not drip. The CCT results indicated that the heat release rate (HRR) of the EVA/LDHs/RP composites with a suitable amount of RP decreased in comparison with that of the EVA/LDHs composites. The SDT showed that RP was helpful to smoke suppression. TG-FTIR data showed that the EVA/LDHs/RP composites show a higher thermal stability than the EVA/LDHs composites. A suitable amount of RP in EVA/LDHs/RP composites resulted in an increase in LOI values, a decrease in the HRR, the achievement of the UL 94 V-1 rating with no dripping phenomenon, a good smoke suppression character, and a high thermal stability.     

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.     

Synergistic flame retardant effects of Fe-OMMT with LDH in EVA/LDH composites

Abstract

The synergistic effects of Fe organic modified montmorillonite (Fe-OMMT) with layered double hydroxides (LDHs) in ethylene vinyl acetate copolymer/LDH (EVA/LDH) composites have been studied using thermal analysis [thermogravimetric analysis (TGA)], limiting oxygen index (LOI), UL-94 test and cone calorimeter test (CCT). The results showed that the addition of a given amount of Fe-OMMT apparently increased the LOI value and the rating in the UL-94 test. The results from the LOI and UL-94 tests show that Fe-OMMT can act as flame retardant synergistic agents in EVA/LDH composites. The CCT data indicated that the addition of Fe-OMMT in the EVA/LDH system can greatly reduce the heat release rate. The TGA data show that Fe-OMMT, as an excellent flame retardant synergist of LDH, cannot increase the thermal degradation temperature and the charred residues.     

碱式硫酸镁晶须阻燃LDPE/EVA复合材料的研究

通过双螺杆挤出机制备了聚乙烯/聚乙烯-醋酸乙烯酯/碱式硫酸镁晶须(LDPE/EVA/MHSH)复合材料,氧指数、UL-94垂直燃烧、锥形量热实验和热重分析表明,MHsH能有效提高材料的阻燃性能和热稳定性.力学性能测试表明,MHSH对聚合物具有一定的增强作用.     

A novel intumescent flame‐retardant system for flame‐retarded LLDPE/EVA composites

A new intumescent flame retardant (IFR) system consisting of ammonium polyphosphate (APP) and charing‐foaming agent (CFA) and a little organic montmorillonite (OMMT) was used in low‐density polyethylene (LLDPE)/ethylene‐vinyl acetate (EVA) composite. According to limiting oxygen index (LOI) value and UL‐94 rating obtained from this work, the reasonable mass ratio of APP to CFA was 3 : 1, and OMMT could obviously enhance the flame retardancy of the composites. Cone calorimeter (CONE) and thermogravimetric analysis (TGA) were applied to evaluate the burning behavior and thermal stability of IFR‐LLDPE/EVA (LLDPE/EVA) composites. The results of cone calorimeter showed that heat release rate peak (HRR‐peak) and smoke production rate peak (SPR‐peak) and time to ignition (TTI) of IFR‐LLDPE/EVA composites decreased clearly compared with the pure blend. TGA data showed that IFR could enhance the thermal stability of the composites at high temperature and effectively increase the char residue. The morphological structures of the composites observed by scanning electron microscopy (SEM) and X‐ray diffraction (XRD) demonstrated that OMMT could well disperse in the composites without exfoliation, and obviously improve the compatibility of components of IFR in LLDPE/EVA blend. The morphological structures of char layer obtained from Cone indicated that OMMT make the char layer structure be more homogenous and more stable. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Combustion characteristics and synergistic effects of red phosphorus masterbatch with expandable graphite in the flame retardant HDPE/EVA composites

In this work, the flammability behaviors and synergistic effects of red phosphorus masterbatch (RPM) with expandable graphite (EG) in flame‐retardant high‐density polyethylene/ethylene vinyl‐acetate copolymer (HDPE/EVA) composites have been investigated by limiting oxygen index (LOI), UL‐94 test, cone calorimeter test (CCT), thermogravimetric analysis (TGA), Fourier‐transform infrared (FTIR) and scanning electron microscopy (SEM). The data obtained from LOI, UL‐94 test and CCT showed that suitable amount of RPM had synergistic effects with EG in the HDPE/EVA/EG/RPM composites. The addition of RPM greatly increased the LOI values by 3.4%, obtained UL‐94 V‐0 rating, decreased the heat release rates and total heat release, and prolongated the ignition time when 6.7 phr RPM substituted for EG in the HDPE/EVA/EG/RPM composites. The data from TGA and FTIR spectra also indicated the synergistic effects of RPM with EG considerably enhanced the thermal degradation temperatures. The morphological observations after UL‐94, CCT, and SEM images presented positive evidences that the synergistic effects took place for RPM with EG, and the flame‐retardant mechanism has been changed in flame‐retardant HDPE/EVA/EG/RPM composites. The formation of stable and compact charred residues promoted by RPM acted as effective heat barriers and thermal insulations, which improved the flame‐retardant performances and prevented the underlying polymer materials from burning. POLYM. ENG. SCI., 55:2884–2892, 2015. © 2015 Society of Plastics Engineers