Preparation and properties of a single molecule intumescent flame retardant

Melamine salt of pentaerythriol phosphate (MPP), as a new single molecule intumescent flame-retardant, was prepared from pentaerythritol, phosphoric acid, and melamine, and then incorporated into polypropylene (PP) with organic montmorillonite (OMT) to obtain flame retardant PP/MPP/OMT composites. The flammability and combustion behavior of flame retardant PP composites were characterized by using LOI, UL-94 test, and cone calorimeter, respectively. The results showed that the flame retardant properties of the composite containing 29.0 wt% MPP and 1.0 wt% OMT are the best among all the composites. The digital photographs after cone calorimeter test demonstrated that moderate OMT could promote to form the homogenous and compact intumescent char layer.     

APP-DAP-CS 膨胀阻燃体系阻燃聚甲醛研究

为提高聚甲醛（POM）的阻燃性能,以聚磷酸铵（APP）-磷酸氢二铵（DAP）-玉米淀粉（CS）为膨胀阻燃体系,将其与POM 通过熔融共混制备了阻燃POM 复合材料。并采用氧指数（LOI）仪、水平垂直燃烧（UL-94）测定仪、热重-差示扫描量热仪（TG-DSC）、扫描电镜（SEM）及锥形量热仪（CONE）等仪器对所制备的样品进行了测试与表征,结果表明：当复配膨胀体系中APP ∶ DAP ∶ CS=4 ∶ 3 ∶ 1 时,阻燃POM 的LOI 可达38,UL-94 等级为V-1 级,热释放速率和总释热量均较小,炭层结构致密稳定,说明APP-DAP-CS 膨胀阻燃体系能够有效抑制POM的燃烧,具有良好的阻燃作用。     

白炭黑对硅橡胶性能的影响

采用电子万能试验机、极限氧指数、垂直燃烧仪、同步热分析仪和锥形量热仪等,系统研究了白炭黑添加量对硅橡胶/白炭黑复合材料的力学性能、阻燃性能、热稳定性和燃烧性能的影响。结果表明：白炭黑能显著提高复合材料的力学性能,白炭黑添加40 份时,复合材料力学性能达到最佳,其拉伸强度为9.35MPa,断裂伸长率为614.7%;白炭黑能改善复合材料的阻燃性能,白炭黑量达到50 份时,复合材料极限氧指数可达25.0%;白炭黑添加能明显提高复合材料的初始热分解温度和高温成炭率,白炭黑添加量为40 份时初始热分解温度为495.4 ℃,高温残炭率为31.4%;白炭黑的添加能有效降低复合材料的热释放速率、总热释放量、总生烟量和二氧化碳生成量,对硅橡胶有较好的阻燃抑烟作用。     

蒙脱土对木材膨胀阻燃涂料性能的影响

采用极限氧指数、锥形量热仪等试验,研究了不同蒙脱土对膨胀阻燃涂料的木材阻燃性能的影响。试验结果表明:复配蒙脱土可以在膨胀阻燃涂料的基础上进一步增加木材的氧指数,涂覆复配阻燃涂料的木材氧指数可达40.8;同时,复配蒙脱土可以降低燃烧热释放速率,并减少总热释放量和总发烟量;采用层状结构显著的蒙脱土,可以更为高效的促进木条成炭,从而起到更好的阻燃抑烟功效。     

Enhanced flame retardancy of natural rubber composite with addition of microencapsulated ammonium polyphosphate and MCM-41 fillers

Microencapsulated ammonium polyphosphate with melamine-formaldehyde resin (MCMF-APP) prepared by in situ polymerization and characterized by FTIR showed decreased water solubility and particle size in comparison to bare ammonium polyphosphate. APP was used as additive to natural rubber (NR) together with mesoporous silica MCM-41 as a synergistic agent to form intumescent flame retardant composite in this study. The flame retardancies of NR/APP, NR/MCMF-APP and NR/MCMF-APP/MCM-41 composites were studied using limiting oxygen index (LOI) and UL-94 test, and their thermal stability was evaluated by thermogravimetric analysis (TGA) and dynamic mechanical thermal analysis (DMTA) as well as physico-mechanical properties. The results indicated that the LOI value of NR/MCMF-APP composite was higher than those of NR/APP composite and NR. Addition of MCM-41 into NR/MCMF-APP composite further increased the LOI values and also increased the UL-94 ratings of most ternary composites to V-0 due to a synergistic effect between MCM-41 and MCMF-APP in NR composites. As the results showed, the thermal stability and flame retardancy of NR were enhanced.     

改性LDH与IFR对聚苯乙烯的协效阻燃研究

制备由聚磷酸铵（APP）、季戊四醇（PER）和十二烷基单磷酸钾改性的锌铝双氢氧化物（ZnAl-LDH-PK）组成的复合阻燃剂与膨胀阻燃剂IFR协效阻燃聚苯乙烯（PS）,研究了二者不同配比下对聚苯乙烯的阻燃性能、燃烧性能。结果表明,适当比例的ZnAl-LDH-PK和IFR协同作用于复合材料,可使材料具有更优异的热稳定性和成炭能力;当组分为PS、22%IFR、3%ZnAl-LDH-PK时,氧指数（LOI）达35,总热释放和生烟总量较纯PS分别降低了28%和38%,提高了耐火性能;SEM结果证实ZnAl-LDH-PK与IFR的协效作用使复合材料形成了高度膨胀和连续致密的炭层。     

Evaluating the influence of varied fire-retardant surface coatings on post-heat flexural properties of glass/epoxy composites

This paper investigates the influence of char-forming, flame-inhibiting and intumescent surface coatings on the post-heat flexural behavior of glass fibre-reinforced epoxy composites exposed to one-sided radiant heating. The fire performance of glass/epoxy laminates surface-coated with varied formulations was evaluated using a cone calorimeter under various external heat fluxes (25, 50 and 65 kW/m²). Self-sustained ignition was significantly delayed for fire-protected laminates relative to the control. The peak heat release rates and the time to reach this event were significantly reduced in thermally-protected laminates. In addition to the chemical nature of flame retardant chemicals present in the coatings, the time to reach the peak heat release rate and the magnitude of the total heat release were influenced by the quantity and morphology of the char formed by each type of surface coating. The post-heat flexural performance of heat-damaged laminates was determined via three-point bending. There was a significant improvement in the post-heat flexural moduli retention in thermally-protected glass/epoxy laminates. This may be due to the flame retardation efficacy of the coatings and the ability of the charred structures to reduce the heat transfer into the substrate thereby protecting the underlying composite and its mechanical integrity.     

聚磷酸铵和三氧化钼对聚氨酯软泡阻燃性能的影响

以聚磷酸铵（APP）和三氧化钼（MoO3）为阻燃剂,采用一步发泡法制备阻燃聚氨酯软质泡沫（FPUF）,通过扫描电镜、氧指数仪、热重分析仪和锥形量热仪等测试手段研究了MoO3和APP对聚氨酯软泡的泡孔结构、热稳定性、阻燃性能以及产烟量的影响规律。研究表明：MoO3和APP均能提高聚氨酯软泡的阻燃性能,与纯聚氨酯软泡相比,当APP和MoO3的添加量均为7.5%时,阻燃聚氨酯软泡的总热释放量和总产烟量分别降低了44.2%、66.3%,表现出很好的阻燃和抑烟性能;探讨了APP和MoO3阻燃聚氨酯软泡的阻燃作用机理,APP在气相和凝聚相发挥阻燃作用,在气相中通过生成含磷官能团捕获气相中的自由基,在凝聚相中发挥催化成炭的作用,MoO3能促进热裂解聚氨酯催化成炭,提高成炭率,使炭层致密,并提高聚氨酯软泡的热稳定性,有效提高聚氨酯软泡的火灾安全性。     

温敏性水凝胶制备及阻燃性能研究

采用甲基纤维素（MC）、聚乙二醇（PEG）、氯化钠（NaCl）为原料制备温敏性水凝胶,并在该体系中添加阻燃剂聚磷酸铵（APP）,优选出材料体系质量分数配比为 MC∶PEG∶NaCl∶APP=1.3∶5.0∶5.0∶1.5。 采 用 试 管 倒 置 法 测 得 其 LCST 为58 ℃。利用傅里叶红外光谱仪（FT-IR）表征产物结构,借助热重分析仪和锥形量热仪分别测试水凝胶的热稳定性以及阻燃性能。实验结果显示,材料配比组分体系没有发生化学作用。对比未处理和水浸泡过的木板,经温敏性水凝胶浸泡后的木板点燃时间和热释放速率峰值出现时间均明显延迟。与未处理木板相比,经温敏性水凝胶浸泡后的木板点燃时间延迟 76 s,第一次和第二次热释放速率峰值出现时间分别延迟 83 s 和 269 s,表明制备的温敏性水凝胶具有良好的阻燃性能。     

可膨胀石墨对改性硅橡胶膨胀及燃烧性能的影响

硅橡胶是有机-无机材料,是一种优良的阻燃材料,在许多领域得到应用,硅橡胶膨胀化后可以扩大其在高端制造和动力电缆防护领域的应用。以可膨胀石墨为膨胀阻燃剂,添加不同含量次磷酸铝制备膨胀硅橡胶材料,研究了硅橡胶的膨胀阻燃性能。采用氧指数（LOI）、垂直燃烧测试（UL-94）、热失重分析（TGA）、膨胀测试、力学性能等手段对其进行了研究。结果表明：次磷酸铝和可膨胀石墨为1:1 时,LOI 达到40.8%,UL-94 达到V-0 等级,力学性能也达到了最佳,从锥量结果看,二者复配时pHRR 从455 kW/m2 降低到259 kW/m2,且膨胀效果好,炭层强度增强。     

CS/h-BN/APP层层自组装涂层阻燃杨木的研究

为提高杨木的阻燃性能,利用带正电性的壳聚糖/六方氮化硼(CS/h-BN)聚电解质溶液,以及带负电性的聚磷酸铵(APP)溶液,基于层层自组装(LBL)技术,通过两聚电解质溶液之间的静电吸附作用,在木材表面成功制备出具有良好阻燃性能的CS/h-BN/APP薄膜涂层.结果表明:所制备的涂层均匀分布在木材表面,且具有良好的附着力;涂层阻燃木材试件的热释放速率、烟释放速率显著降低,第2放热峰出现时间晚于未处理木材试件,且在燃烧过程中的残余物质量始终高于未处理木材试件,完全燃尽时间则比未处理木材试件多出约100s,阻燃效果随着自组装涂层数的增加而逐渐增强;涂层阻燃木材试件的CO、CO_2气体生成量明显降低,表明阻燃涂层能有效降低木材烟气及毒性气体释放;涂层阻燃木材试件较未处理木材试件更好地保持了木材本身的结构,显示出了良好的抵抗火灾能力.     

木质素基环保型纤维板的阻燃性能

以木质纤维、木质素磺酸铵、尿素为原料,并添加磷酸二氢铵阻燃剂,然后通过高温热压处理工艺制备木质素基环保型纤维板.采用锥形量热仪测试了阻燃剂对纤维板阻燃性能的影响.结果表明:阻燃剂促进了纤维板的成炭过程,降低了纤维板的热释放速率、烟比率峰值和CO_2释放速率,减少了可燃性挥发物的产生,使纤维板的阻燃性能得到明显改善.     

植酸三聚氰胺盐阻燃环氧树脂研究

利用生物基阻燃剂植酸三聚氰胺盐 (MPA) 阻燃改性环氧树脂并对其性能进行研究。通过红外光谱 (FTIR) 以及X射线光电子能谱 (XPS) 对MPA化学结构进行表征。利用热重分析仪 (TGA)、极限氧指数测试仪 (LOI)、垂直燃烧测试仪 (UL-94) 及锥形量热测试仪 (CC) 研究阻燃环氧树脂的热稳定性及阻燃性能。热重分析结果表明，MPA阻燃剂在800 ℃残炭达到25.6%，引入环氧树脂后可提升材料高温区热稳定性。垂直燃烧测试显示MPA在15%添加量下可赋予环氧树脂UL-94 V-0等级，表明MPA对环氧树脂有较好的阻燃效果。进一步锥形量热结果表明，MPA的加入显著降低了环氧树脂的热释放速率及总热释放，同时表现出优异的抑烟性能。     

功能化苯基膦酸镧在环氧树脂中的阻燃作用研究

为提高环氧树脂（EP）的热性能和阻燃性,以回流法合成了层状苯基膦酸镧（LaPP）,并用六氯环三膦腈（HCCP）进行表面接枝改性,得到HCCP-LaPP,将其用于环氧树脂中制备EP/HCCP-LaPP复合材料;研究LaPP和HCCP的协同作用对EP阻燃性能、热性能的影响。结果表明,添加HCCP-LaPP能明显改善EP复合材料在较高温度下的热稳定性和残留量。锥形量热仪测试结果表明,与纯EP相比,EP/6%HCCP-LaPP复合材料的总热释放量和总烟气释放量分别降低了39.9%和24.6%。同时,氧指数值从25.7提高到30.3,垂直燃烧UL-94等级从NR提高到V-1。在700 ℃,EP/6%HCCP-LaPP复合材料的残留量为25.7%,而EP只有18.5%。说明HCCP-LaPP在阻燃EP中具有良好的阻燃作用,LaPP和HCCP优异的成炭作用、片层阻隔作用及磷氮协效使EP复合材料的阻燃性、抑烟性和热稳定性显著提高。     

硅氧烷黏度和云母粉含量对有机硅泡沫的影响

以不同黏度α,ω-二羟基聚硅氧烷和端乙烯基聚二甲基硅氧烷为原料,云母粉为无机填料,制备有机硅泡沫。采用扫描电子显微镜、氧指数、锥形量热和热重分析等测试手段,研究硅氧烷黏度和无机填料含量对有机硅泡沫微观形貌、阻燃性能和热稳定性的影响。结果表明,硅氧烷黏度的变化会极大地影响有机硅泡沫的微观形貌和热稳定性;α,ω-二羟基聚硅氧烷黏度的升高对有机硅泡沫的阻燃性能起到负面影响,而端乙烯基聚二甲基硅氧烷黏度的变化对其阻燃性能影响较小;另外,无机填料的引入能够显著降低有机硅泡沫的泡孔孔径,并极大地提升其阻燃性能和热稳定性。     

Outlining the mechanism of flame retardancy in polyamide 66 blended with melamine-poly(zinc phosphate)

Glass-fiber reinforced polyamide 66 is flame retarded with a mixture of melamine-poly(zinc phosphate), (Safire^®400) and diethyl aluminium phosphinate. The performance of this synergistic combination of additives is multi-modal and a comprehensive investigation is undertaken to elucidate the underlying flame retardancy mechanism. The strategy was to characterize the different chemical species responsible for flame retardancy that are generated in gas and condensed phases under different fire scenarios. Following heat release rate (HRR) curve of flame retarded polyamide formulations obtained by mass loss calorimeter, samples in different stages of degradation are collected and investigated. Further flame retardants and formulations were degraded in tubular furnace whose temperature protocol relied on thermal degradation profile obtained from thermogravimetric analysis (TGA). In either case, species generated in condensed phase were studied by solid state nuclear magnetic resonance spectroscopy (magic angle spinning (MAS) NMR; ²⁷Al, ³¹P and ¹³C), Fourier transform Infra-red spectroscopy (FTIR), X-ray powder diffraction (XRD), electron probe microanalysis (EPMA), scanning electron microscopy (SEM), and optical microscopy, whereas TGA coupled FTIR, and pyrolysis gas chromatography mass spectrometry (Py/GC/MS) were utilised to investigate species released in gas phase. Flame retardancy mechanism is elaborated based on the identification of the chemical species in both gas and condensed phases and their specific contributing role.     

陶瓷填料对硅橡胶复合材料性能的影响

选择玻璃粉和云母粉作为陶瓷填料添加到硅橡胶中,制备了可陶瓷化硅橡胶复合材料,并研究了80份陶瓷填料及玻璃粉与云母粉比例对硅橡胶的力学性能、阻燃性能、热稳定性和陶瓷化性能的影响.结果表明:陶瓷填料对硅橡胶复合材料的力学性能影响较大,添加30份玻璃粉和50份云母粉时拉伸强度最大可达到5.96 MPa,断裂伸长率为421.3...     

石墨烯微片对环氧树脂热性能的影响研究

研究石墨烯微片（GNS）对特种环氧树脂（AG-80/JD-919）的热稳定性和燃烧性能的影响。首先采用溶液共混法将GNS 添加到环氧树脂中,并利用热重分析仪（TGA）和锥形量热仪（CCT）分别对阻燃环氧树脂进行热稳定性和阻燃性能的测试分析。结果表明,GNS 添加量为6%时,环氧树脂的残炭量提高了4.6%,同时峰值热释放速率（pHRR）和总热释放量（THR）分别降低了40.63%和15.43%。因此,GNS 能够改善环氧树脂的热稳定性及其阻燃性能,这主要与GNS 在环氧树脂基体热分解过程能够起到物理阻隔作用有关。     

微胶囊化阻燃剂对防火涂料的性能影响

针对普通水性膨胀型防火涂料在使用过程中耐水性差的问题,应用在阻燃剂领域的微胶囊技术,自制水性膨胀型防火涂料。将含密胺包裹聚磷酸铵或普通聚磷酸铵的两种防火涂料进行试验,对比两种涂料的防火性能、热稳定性和耐水性能。结果表明:密胺包裹APP的热分解温度比普通APP的热分解温度提高了约100~150℃。采用微胶囊技术包裹APP可使膨胀型防火涂料的耐水性得到很大改善,受火后炭层内部较添加普通型APP的涂料致密,能起到持久有效的防火作用。     

Evaluating Models for Predicting Full-Scale Fire Behaviour of Polyurethane Foam Using Cone Calorimeter Data

Two models that can be used to predict full-scale heat release rates of polyurethane foam slabs were evaluated in this study. Predictions were compared with results of furniture calorimeter tests of 10 cm thick polyurethane foam specimens which were ignited in the centre or on the edge. Furniture calorimeter results indicated that peak heat release rates and fire growth rates were higher during centre ignition tests than edge ignition tests. For both situations, the growth phase of the heat release rate curves measured in the full-scale tests was successfully predicted using t ² design fires; the choice of a specific t ² fire depended on the surface area of the specimen and ignition location. A model originally developed during the European Combustion Behaviour of Upholstered Furniture (CBUF) project was also evaluated using heat release rate data from cone calorimeter tests and flame area burning rates measured using infrared video records of the furniture calorimeter tests. This model was able to successfully predict the initial growth phase of the fires and predictions of peak heat release rates were within 17% of measured values. The model had less success in predicting heat release rates later in the growth phase and during the decay phase of the fires, and did not appear to capture all of the physics of the full-scale tests, in particular foam melting and subsequent liquid pool burning. As the model did show promise, future work is planned to address these shortcomings and to develop improved flame spread models for polyurethane foam.