水性超薄膨胀型钢结构防火涂料的制备

以有机硅改性的丙烯酸酯乳液为基料,多聚磷酸铵(APP)、季戊四醇(PER)、三聚氰胺(MEL)为膨胀阻燃体系,制备水性超薄膨胀型钢结构防火涂料;采用硼酸和可膨胀石墨(EG)改性防火涂料。研究表明,同时用w(硼酸)=4%,w(EG)=5%改性防火涂料,涂层的耐火极限达到93 min,热失质量分析(TGA)测试表明w(硼酸)=4%,w(EG)=5%共同改性的防火涂料在700℃时最终残炭量是44%。扫描电镜(SEM)分析结果表明硼酸/EG改性的残炭层形成了致密的"蜂窝"状结构。     

可膨胀石墨在膨胀型钢结构防火涂料中的应用研究

为了克服钢结构防火涂料膨胀发泡层蓬松易脱落和易开裂的缺点,采用可膨胀石墨来改善防火涂料发泡层的结构.研究了可膨胀石墨对发泡层形貌和钢结构耐火极限的影响.结果表明,可膨胀石墨膨胀后成"蠕虫"状穿插于发泡层中,起到增强作用,使炭质层结构更致密.采用膨胀容积为180 mL/g、粒径为0.18 mm、起始膨胀温度为150 ℃的可膨胀石墨时,当添加量为3%时具有较好的改性作用.     

Fe_2O_3与可膨胀石墨对膨胀防火涂料热降解与防火性能的影响

研究了2种改性材料对膨胀防火涂料热降解和防火性能的影响。防火涂料由聚磷酸铵(APP)-季戊四醇(PER)-三聚氰胺(MEL)膨胀阻燃体系、两种树脂基体和溶剂组成。可膨胀石墨(EG)和氧化铁(Fe2O3)作为改性材料添加于涂料中,以提高涂料的防火性能和热稳定性。对于EG、Fe2O3和EG/Fe2O3对涂料防火性能、膨胀炭质层的热稳定性采用热质(TGA)、X-光电子能谱(XPS)和扫描电镜(SEM)进行了系统的分析。实验结果表明:对于膨胀炭质层而言,Fe2O3提高了其热稳定性,EG影响了其微观结构,而EG/Fe2O3则结合了2种材料的优点使涂料的防火性能得到了进一步提高。     

可膨胀石墨改性APP/PER/MEL防火涂料的热降解研究

将可膨胀石墨（EG）加入到APP／PER／MEL防火涂料中，得到EG改性涂料。运用隔热实验分析和热重分析（TGA）测试APP／PER／MEL涂料和EG改性涂料的耐火极限、残炭率。结果表明：EG掺量为1％～7％，可延长耐火极限5～35min；掺入5％的EG可使涂料800℃时残炭率提高约12％。通过扫描电镜（SEM）分析和Flymn—Wall—Ozawa、Kissinger方法计算热降解过程中两个阶段的活化能，推测EG能延长耐火极限和提高残炭率的原因为EG自身的膨胀形成“蠕虫”状结构改善了炭层的微观结构，并大幅度提高了热降解过程的热稳定性。     

海泡石和EG对水性膨胀型钢结构防火涂料的影响

采用可膨胀性石墨(EG)和海泡石对传统的APP/PER/MEL膨胀型防火涂料体系进行改性,制备了一种新型水性超薄膨胀型防火涂料,并采用防火性能测试装置、热重分析(TGA)、差热重量分析(DTG)及X射线衍射(XRD)等方法对该防火涂料的耐火性能、热降解过程、炭化层结构进行了研究。热分析结果表明,海泡石与EG复合使用,将充分发挥它们的协同作用:EG在较低温度区域能够延缓炭化层的形成,而海泡石则能够在高温区域阻止炭化层氧化分解,并提高成炭率从而达到阻燃的目的。XRD结果显示,复合使用EG和海泡石能够促进炭化层中TiP2O7的形成,在高温阶段保护炭化层不被氧化。当防火涂料中添加质量分数3%海泡石和质量分数2%EG,涂层厚度为1.0 mm时,钢材的耐火时间达到72 min。     

室内水性膨胀型防火涂料的性能测试

用壁挂式酒精喷灯模拟火灾现场,对一种室内水性膨胀型钢结构防火涂料的耐火极限和膨胀倍数进行测试。采用热重/差热(TG/DTG)对涂料的热稳定性进行表征,用红外光谱(IR)和X-射线衍射(XRD)分析燃烧后炭层结构,用数码相机和SEM观察炭层的形貌。结果表明,该涂料的耐火极限为160 min,膨胀倍数为12.2,最大失重温度为328℃,涂料受热分解后生成含有P—C—O、—CH_2—、■和—OH结构的炭化物,炭层中含有TiO_2与TiP_2O_7,且炭层呈现"蜂窝状"多孔结构。该防火涂料的性能符合GB 14907—2018《钢结构防火涂料》国家标准,性能优异,在室内钢结构的防火保护中可以广泛使用。     

水性钢结构防火涂料的制备及其耐火性能研究

以水性树脂为基体,聚磷酸铵(APP)、三聚氰胺(MEL)、季戊四醇(PER)为膨胀阻燃体系,可膨胀石墨(EG)和绢云母为填料制备了水性膨胀型钢结构防火涂料;研究了基体拼合、膨胀阻燃体系、EG与绢云母配比对钢结构防火涂料性能的影响。结果表明:氯偏乳液与纯丙AC261P乳液质量比为22:3,APP、MEL、PER的质量比为4:3:3,可膨胀石墨和绢云母的质量比为5:3时,制备的防火涂料涂层受热膨胀倍率为5.68倍,形成了"蜂窝状"结构的膨胀炭质层,孔洞均匀致密,与钢板粘附性好、强度高,耐火性能好,耐火极限高达2 997 s。     

可膨胀石墨在水性饰面防火涂料中的应用

以可膨胀石墨(EG)为物理膨胀体系,制备了膨胀型水性饰面防火涂料,采用小室法、锥形量热仪(CONE)、扫描电镜(SEM)等手段分析了可膨胀石墨及其与阻燃协效剂复配对饰面膨胀型防火涂料性能的影响。研究发现,EG的加入改善了膨胀炭质层的结构,大大提高了涂料的防火性能。选用3.5g、80目的EG,所得涂料的防火性能最佳,耐火时间达33min。可膨胀石墨与阻燃协效剂复配能够进一步降低涂料燃烧的烟气释放。当EG与二氧化锡按质量比为1∶1复配,所得涂层的生烟速率峰值与仅含EG的涂层相比下降78.4%,抑烟性能最好。     

水性膨胀型钢结构防火涂料的制备及性能研究

以醋酸乙烯、叔碳酸乙烯酯聚合而成的混合液为基体,采用物理膨胀和化学膨胀相结合的阻燃膨胀体系,可膨胀石墨（EG）为物理膨胀体系,水性阻燃剂为化学膨胀体系,来制备水性膨胀型钢结构防火涂料。探究了乳液与阻燃剂之间的配比、EG的添加量对水性防火涂料防火性能的影响。结果表明,当乳液含量在20%（质量分数,后同）、阻燃剂含量在40%、EG含量在1.5%时,制备的水性膨胀型防火涂料涂层受热后膨胀效果显著,强度高,附着力好,耐火极限为63min,满足GB14907—2018对钢结构的防火要求。     

MoO3与可膨胀石墨改性聚磷酸铵/季戊四醇/三聚氰胺防火涂料研究

采用MoO3、可膨胀石墨(EG)和MoO3/EG对APP/PER/MEL膨胀防火涂料进行改性,制备成改性涂料,运用隔热性能分析和热重分析(TGA)测试改性涂料的耐火极限和残碳率.结合扫描电镜分析结果,探讨MoO.EG和MoO3/EG对涂料耐火性能提高的途径分别为MoO3通过与APP/PER/MEL涂料体系作用提高了涂料残碳率;EG通过自身膨胀产生"蠕虫"结构显著改善了碳层结构;而MoO3/EG则通过MoO3和EG各自的作用,产生了明显的协同增效效果.     

Improving the fire performance and smoke suppression of expandable polystyrene foams by coating with multi-dimensional carbon nanoparticles

Expandable graphite (EG) and modified multi-wall carbon nanotubes (ATH-MWNT) were introduced to expandable polystyrene (EPS) foams in order to improve its fire performance. The fire performance of EPS foams was evaluated by limiting the oxygen index (LOI), vertical burning (UL-94), and cone calorimetry tests. The results showed that the presence of 14.3% EG and 4.1% ATH-MWNT increased the LOI value from 18.0 to 30.3%, upgraded the UL-94 rating from no rating to V-0, completely eliminated melt dripping, and significantly decreased the peak heat release rate from 933 to 177 kW/m². Thermal analysis indicated that the thermal stability and char formation were improved by the presence of flame retardants. The char morphology was characterized by scanning electronic microscopy (SEM). It was suggested that the presence of EG and ATH-MWNT could form integrated char layers during combustion, which was beneficial to the formation of an intumescent protective char structure.     

Flame retardancy of different‐sized expandable graphite particles for high‐density rigid polyurethane foams

The effects of expandable graphite (EG) of different particle sizes, on the fire‐retardant properties of high‐density rigid polyurethane foam (RPUF) (0.45 g cm^?3) were studied. Samples of EG with different particle sizes were obtained by pulverization in an ultra‐high‐speed mixer for 4 and 13 min, respectively. It was shown that as received (EG0) and 4 min pulverized EG (EG4) efficiently improved the fire‐retardant properties of RPUF composites, while 13 min pulverized EG (EG13) did not. The char of the burned composites filled with EG0 and EG4 covered the whole surface of the samples and formed a complete physical barrier. This barrier material prevented combustible gases from feeding the flame and also isolated oxygen efficiently from the burning material. EG13 did not produce enough char to cover the whole surface of the burning sample, resulting in poor fire‐retardant property of the RPUF composites. Thermal degradation tests of the foams by thermogravimetric analysis indicated that EG showed negligible effects on the thermal stability of the RPUFs. Copyright © 2006 Society of Chemical Industry     

Effects of expandable graphite on char morphology and pyrolysis of epoxy based intumescent fire-retardant coating

The current study was designed to investigate the effects of expandable graphite (EG) on fire protection properties of intumescent fire-retardant coating for steel structures. Several formulations of intumescent coating were prepared and tested according to ISO 834 for char expansion. The chars were found without cracks and bonded with the steel substrate. The results showed that the coating slowly degraded during the test and char remained in contact with vertically tested coated substrate. The coated substrates were also tested for weather resistance using humid and ultraviolet environment. The char was characterized by using FESEM, XRD, FTIR, TGA, and XPS analysis. FESEM examined char morphology of the coatings after furnace fire test. XRD and FTIR showed the presence of graphite, borophosphate; boron oxide and sassolite in the char. TGA and DTGA results disclosed that EG improved the residual mass of coating. XPS analysis showed the percentages of carbon and oxygen are 48.50 and 43.45 in char of formulation with 12.8% EG. The results of weathering test coatings showed decreased in char expansion because of a humidity and UV light. The formulation with 9.8% EG showed the maximum char expansion and high residual mass among the formulations investigated in this study. The weathering tested coated samples showed their capability of fire protection.     

Effect of expandable graphite and ammonium polyphosphate on the thermal degradation and weathering of intumescent fire-retardant coating

This research aims to study the effect of ammonium polyphosphate and expandable graphite on the intumescent coating formulations (ICF). The coating presented in this research article is based on carbon source expandable graphite (EG), blowing agent melamine, acid source ammonium polyphosphate (APP), epoxy resin as a binder with polyamide amine. The stability of the developed coating was verified at 950°C for 1-hour fire test. The results showed that the coating is stable and well bond with the steel substrate. The char was characterized by using FESEM, XRD, FTIR, DTA, TGA, XPS, Py-GCMS and Weathering Test. The morphology of the char was studied by SEM of the coating after furnace fire test. XRD and FTIR show the presence of graphite, borophosphate; boron oxide and sassolite in the residual char. TGA and DTG disclosed that EG improved the residual mass of coating. XPS analysis showed the char residue of IF5-APP-EG contains carbon and oxygen contents 47.50 and 40.70, respectively. Py-GCMS analysis described that the IF5-APP-EG released less gaseous compounds. The weathering test illustrated that's the char expansion of coatings samples was decreased due to the presence of a humid environment and UV light. The IF5-APP-EG showed the maximum char expansion, lower substrate temperature and high residual weight among the studied formulations.     

膨胀型不饱和聚酯树脂防火涂料的研制

采用191^#不饱和聚酯树脂为基体树脂,以聚磷酸铵、三聚氰胺和季戊四醇为防火助剂,辅以填料和其他助佑剂,配制膨胀型防火涂料.讨论了基体树脂和防火体系的配比对防火涂料性能的影响,分析了涂层厚度和燃烧时间对膨胀层高度的影响.实验结果表明,该防火涂料具有较好的理化性能,在涂层厚度为1.90 mm时,其耐火极限超过240 min.     

LL阻燃剂的加入对防火涂料性能的影响

在防火涂料中加入了LL阻燃剂后,通过采用小室燃烧试验法、产烟试验、热分析仪、电子显微镜等实验检测和分析结果为依据,指出使用LL复合阻燃剂是进一步提高防火涂料性能的途径之一.提出LL阻燃剂的加量在15%时,防火涂料既有很好的防火性能,又有优良的理化性能.     

水性超薄膨胀型防火涂料的制备与性能研究

以水性乳液为基体,化学膨胀与物理膨胀相结合的阻燃膨胀体系,其中聚磷酸铵（APP）、 三聚氰胺（ MEL）、双季戊四醇（ DPE）为化学膨胀体系,可膨胀石墨（ EG）、石英纤维为物理膨胀体系,制备水性超薄膨胀型防火涂料。考察了基体类型、膨胀阻燃体系配比对水性防火涂料防火性能的影响。结果表明,聚醋酸乙烯酯乳液与纯丙乳液质量为比 1∶1时, APP/MEL/DPE的质量比为 10∶6∶5,EG与石英纤维的用量均为 3%时,制备的防火涂料涂层受热膨胀效果显著,与基材附着力好,强度高,机车地板结构耐火时间达到 60 min,满足 HG/T5367. 4—2020对结构件的防火要求;有助于实现轨道交通车辆结构防火的更高要求,完成进口产品在轨道交通行业的国产化替代。     

可膨胀石墨和碳纳米管对PMMA火蔓延特性的影响

通过熔融共混法制备了9种PMMA复合阻燃材料,对其进行小尺寸的水平火蔓延实验研究,对比分析了可膨胀石墨(EG)和碳纳米管(Carbon Nanotube, CNTs)阻燃剂的加入对材料燃烧特性的影响,主要研究了火蔓延速度、火焰形态、固相温度、质量损失速率等火蔓延特性参数变化规律。结果表明,EG能产生阻燃效应,随EG含量增加,复合材料的火蔓延速度、质量损失速率、表面热流密度均有所减小;CNTs表现出拮抗和协同阻燃的复合效应。EG含量较低时,添加1% CNTs反而会使火蔓延速率加快;随着EG含量增加,拮抗作用逐渐消失,最后表现为协同阻燃,原因是CNTs的高热导率、“灯芯效应”促进表面燃烧作用和EG/CNTs体系阻燃性之间存在竞争关系;添加EG和CNTs前后,火蔓延过程中表现出明显不同的燃烧行为,未添加阻燃剂前PMMA会产生熔融滴落物积聚成池火,表现为明显的热塑性材料燃烧特征;加入EG和CNTs后则会形成碳层,表现为明显的可碳化材料燃烧特征。     

新型阻燃体系对木塑防火涂层阻燃性能的影响

采用隔热性能试验、热失重分析(TG)、傅里叶红外光谱分析(FTIR)以及显微分析等方法,研究了两种改性材料膨胀石墨(EG)和云母对膨胀防火涂层防火性能和热降解行为的影响。结果表明:EG与云母加入后不会改变涂层的基本阻燃进程,且会提高膨胀炭质层的热稳定性,涂层的阻燃效果显著改善。