MCA-ADEPH磷-氮协同阻燃剂的制备及其对PA6阻燃性能的影响

在三聚氰胺(ME)和氰尿酸(CA)分子自组装合成三聚氰胺氰尿酸盐(MCA)的过程中加入二乙基次磷酸铝(ADEPH)合成一种改性MCA,磷-氮协同阻燃剂MCA-ADEPH,并对其结构进行表征;在尼龙6(PA6)中加入MCA和改性MCA,通过熔融共混的方法制备无卤阻燃PA6/MCA和PA6/MCA-ADEPH复合材料,并研究其阻燃性能和力学性能。结果表明,MCA-ADEPH中ADEPH对MCA只是物理改性,ADEPH可细化MCA粒径;MCA-ADEPH可提高PA6/MCA的阻燃性能,MCA和ADEPH可从气相和凝聚相协同阻燃PA6;在提高PA6阻燃性能的同时,PA6的力学性能并没有下降。     

MCA阻燃剂的合成及其在PA6中的应用

目的用一种新的方法合成三聚氰胺氰尿酸盐(MCA),并探究其在聚酰胺6(PA6)中的应用。方法将三聚氰胺(MA)、氰尿酸(CA)和少量水混合成膏状物,并使其在室温下反应一定时间,再加入少量MCA,使其继续反应以制备MCA阻燃剂。将制备的MCA与PA6熔融共混制备阻燃PA6复合材料,用FTIR,XRD,TG,SEM对制备的MCA进行表征,对阻燃PA6复合材料的阻燃和力学性能进行测试。结果所制MCA的FTIR和XRD特征峰与在水中合成MCA的特征峰一致;所合成的MCA最大热失重温度达到451.7℃。在阻燃剂质量分数为8%时,阻燃PA6复合材料的极限氧指数(LOI)为29%,阻燃性能达到UL-94V0级。随着阻燃剂含量的增加复合材料的力学性能有所降低,当阻燃剂质量分数为8%时,拉伸强度为66.4 MPa,冲击强度为4.7 kJ/m~2。结论用文中方法合成的MCA具有工艺简单、不需加热、耗水量低等优点,大大提高了PA6复合材料的阻燃性能。     

三聚氰胺氰尿酸盐的原位制备及填充PA6的阻燃与力学性能

采用反应性加工技术实现了三聚氰胺氰尿酸盐(MCA)的原位制备及阻燃尼龙6(PA6)复合材料的一体化制备。其中SEM分析表明,PA6基体树脂中原位生成的MCA为长纤状粒子,长径比高达20。当阻燃剂添加量为10%(质量分数,下同)时,材料的阻燃性能达UL94V-0(1.6 mm&3.2 mm)级,拉伸强度为70.6 MPa,缺口冲击强度为5.0 kJ/m2,远优于传统MCA阻燃PA6。     

高流动性尼龙6/改性MCA阻燃复合材料的性能

将氧化石墨烯(GO)改性的三聚氰胺氰尿酸盐(m MCA)、未改性的三聚氰胺氰尿酸盐(MCA)分别与高流动性尼龙6(HFPA6)熔融共混,制备出HFPA6/m MCA复合材料和HFPA6/MCA复合材料。研究了MCA改性前后的结构、阻燃复合材料的阻燃性能、热稳定性和力学性能,结果表明:HFPA6/m MCA复合材料的阻燃性能、拉伸强度、弯曲强度和成炭效果比HFPA6/MCA复合材料有很大的提高,冲击强度略有降低,在阻燃剂含量为14%时复合材料的阻燃性能达到UL 94 V-0级。     

苯代三聚氰胺改性三聚氰胺甲醛/聚乙烯醇纤维的结构与性能EI北大核心CSCD

通过湿法纺丝,分别制备了湿拉伸倍数为1.0~1.3倍的三聚氰胺甲醛/聚乙烯醇(MF/PVA)纤维和苯代三聚氰胺(BG)改性MF/PVA纤维。采用红外光谱仪、元素分析仪、极限氧指数(LOI)仪、扫描电子显微镜、热重分析仪和纤维强伸度仪表征对比了BG改性前后MF/PVA纤维的结构和性能变化。结果表明,湿法纺丝可制得结构均匀、表面附着有MF颗粒的MF/PVA纤维及BG改性纤维;随纤维湿拉伸倍数的增大,改性前后纤维的氮流失率都明显增加,阻燃性能和热稳定性能变差,而纤维力学性能增强。加入BG改性后,MF/PVA纤维的氮流失率明显降低,阻燃性能和耐热性能变好,纤维强度有所下降,但纤维韧性明显增大。湿拉伸1.3倍的BG改性MF/PVA纤维,其LOI值为29.1%,纤维的拉伸强度和断裂伸长率分别为2.39cN/dtex和5.66%。     

PBT/PA6/EP-0199共混物及其纤维结构性能

利用双酚A型环氧树脂(EP-0199)对聚对苯二甲酸丁二醇酯(PBT)和聚酰胺6(PA6)共混物进行增容,并对增容后的共混物进行熔融纺丝。采用扫描电镜、差式扫描量热、热重分析、X射线衍射及拉伸试验对比研究增容剂含量变化对共混物及其纤维热性能、力学性能、结晶性能及相形态的影响。结果表明,在PBT/PA6共混比为70∶30(wt,质量比)体系中,加入EP-0199,可有效改善PBT、PA6共混物的相容性。EP-0199的用量存在一个最佳值,在用量低于此值时,共混体系相容性及纤维综合性能随其加入量的增加而提升,当用量高于此值时,EP-0199的增容作用减弱,共混物纤维的综合性能也呈现下降趋势。     

MCA-MMT的制备及其对玻璃纤维增强聚丙烯复合材料阻燃性能的影响

为了提高玻璃纤维(GF)增强聚丙烯(PP)复合材料(GF/PP)的阻燃性能,通过在蒙脱土(MMT)悬浮液中进行三聚氰胺氰尿酸盐(MCA)分子自组装制备了新型协效成炭剂MCA-MMT,并采用FTIR、XRD、SEM和TGA对MCA-MMT的结构及热性能进行了表征;将MCA-MMT、无卤膨胀型阻燃剂与GF/PP熔融共混制备了阻燃复合材料MCA-MMT/(GF/PP),通过极限氧指数(LOI)测试、垂直燃烧试验和锥形量热测试研究了MCAMMT对GF/PP的阻燃效果和阻燃机制,并测试了复合材料的力学性能。结果表明:MMT的加入会影响氰尿酸和三聚氰胺在MCA合成过程中的氢键作用,干扰和抑制大平面氢键网络的形成,减少MCA氢键复合体的分子体积,使颗粒变小。MCA-MMT/(GF/PP)的UL-94防火等级达到V-0级,LOI为31.3%。MCA-MMT的阻燃效率高于传统MCA的,可降低材料燃烧的热释放程度和总烟释放量,使复合材料的阻燃性能提高,其阻燃机制为片层结构的MMT可提高MCA的成炭量,使MCA-MMT/(GF/PP)燃烧后能形成致密的残留炭层。MCA-MMT/(GF/PP)的拉伸、冲击强度与MCA/(GF/PP)的相比并未下降。     

三聚氰胺氰尿酸盐改性PPO/PS复合材料的燃烧性能和流动性能

以无卤阻燃剂三聚氰胺氰尿酸盐(MCA)为改性剂, 采用熔体共混法制备了改性聚苯醚/聚苯乙烯 (PPO/PS)复合材料。通过XRD和SEM对MCA-PPO/PS复合材料的微观结构进行了表征, 重点研究了复合材料的燃烧性能和流动性能。研究发现: 在复合材料的制备和加工过程中MCA的微观结构并没有发生任何变化, 因此复合材料中MCA的阻燃作用不变。MCA在复合材料中分散比较均匀, 无明显团聚现象。与纯PS相比, 质量比为100:100的PPO/PS在燃烧时的氧指数增加5.4%, 热释放速率峰值降低33.1%, 但总烟释放量增加近1.5倍。在PPO/PS中加入MCA后得到的复合材料的阻燃性能随着MCA用量增加而逐渐增强, 发烟量大幅度降低, 同时熔体黏度减小, 流动性增加。在MCA-PPO/PS复合材料中加入5%、 25%和45%质量分数的MCA可分别使复合材料的总烟释放量比PPO/PS降低43.7%、 82.6%和91.6%。PPO/PS的阻燃机制为凝聚相成炭阻燃, 随着MCA用量增加, MCA-PPO/PS复合材料的阻燃机制逐渐转变为气相稀释和对聚合物基体的冷却效应。加入MCA对MCA-PPO/PS复合材料可同时起到阻燃、 抑烟和改善加工流动性的作用。     

PA6/PTT共混物的吸水性和力学性能

由螺杆挤出机制备了尼龙6(PA6)和聚对苯二甲酸丙二醇酯(PTT)的共混物PA6/PTT。通过浸水实验,结合扫描电镜观察和热分析,研究了不同组分PA6/PTT共混物的吸水性能,并进行了相关力学性能测试。结果表明,PA6/PTT共混物吸水率随PTT含量增加而减小,即PTT的加入有效抑制了PA6的吸水率;在相同吸水条件下,PA6/PTT共混物的一般力学性能明显优于PA6,当PTT含量为20%时,共混物吸水后的拉伸、弯曲强度分别较PA6提高了20.98%和71.73%。     

多单体接枝聚丙烯对干态和湿态玻纤增强尼龙6性能的影响

通过熔融共混法,加入自制的多单体接枝聚丙烯(PP-g-MAH-EP)制备尼龙6(PA6)/玻璃纤维(GF)/PP-g-MAH-EP复合材料。研究了PP-g-MAH-EP对复合材料吸水前后静态和动态力学性能的影响,并通过扫描电镜与原子力显微镜分析试样断面微观形貌及微观力学性质的变化。结果表明,PA6/GF/PP-g-MAH-EP复合材料的吸水率随着PP-g-MAH-EP含量的增加逐渐降低,即PP-g-MAH-EP的加入能有效抑制PA6/GF复合材料的吸水率;在干态及相同吸水条件下,PA6/GF/PP-g-MAH-EP复合材料的力学性能明显优于PA6/GF。与PA6/GF相比,当PP-g-MAH-EP加入20 phr时,复合材料综合力学性能最好。PP-g-MAH-EP的加入,有效改善了纤维与尼龙6基体界面的粘接,吸水后的基体树脂在探针作用下的形变量明显降低。     

改性三聚氰胺氰尿酸盐阻燃PA6的研究

用改性三聚氰胺氰尿酸盐阻燃剂阻燃尼龙6。利用改性MCA在与PA6复合过程中可熔融、软化、变形的特性．实现阻燃剂在树脂中的超细均匀分散;研究了改性MCA的凝聚相阻燃增效机理。     

三聚氰胺氰尿酸盐与聚磷酸铵协同作用对环氧树脂阻燃性能的影响

采用氧指数法（LOI）、垂直燃烧法（UL-94）及热重分析法（TGA）对三聚氰胺氰尿酸盐（MCA）和聚磷酸铵（APP）阻燃环氧树脂的阻燃性及热稳定性进行了研究。TGA结果表明,MCA促进成炭的作用较弱,主要在气相起到阻燃的作用。而APP的添加虽然降低了环氧树脂的初始分解温度,但当温度高于400℃时,体系具有更好的热稳定...     

The influence of fibre properties of the performance of glass-fibre-reinforced polyamide 6,6

We discuss the effect of fibre strength and diameter on the balance of mechanical properties of glass-reinforced polyamide 6,6. The results show that the elastic properties of injection-moulded short-glass-fibre-reinforced polyamide 6,6 are not strongly influenced by fibre diameter in the 10–17 micron range. The ultimate properties of these composites (strength and Izod impact behaviour) showed a clear dependence on fibre diameter and were increased by the presence of high-strength S-2 glass fibres. The relationship between the observed mechanical properties and the length, diameter and orientation of the fibres is explored. We have measured fibre length as a function of diameter in composites containing a single glass-reinforcement product and blends of two glass products. The reduction in glass-fibre length from glass-fibre production to final composite moulding has been followed step by step. The final composite mechanical properties, the fibre length, strength, diameter and orientation are all inter-related.     

一步法合成三聚氰胺多聚磷酸盐及其阻燃玻纤增强PA6的研究

三聚氰胺多聚磷酸盐(MPP)是一种重要的氮磷复合型阻燃剂,目前多采用两步法合成.本研究以三聚氰胺和多聚磷酸为原料,在有机溶剂中经一步反应合成MPP,采用XRD、红外光谱、TGA表征了产物结构;该方法具有工艺简单、耗能低、产品性能优良等优点.MPP(25%)阻燃30%玻璃纤维增强PA6可通过UL94V0级别,氧指数达到32;材料力学性能优异,拉伸强度和简支梁缺口冲击强度分别达104MPa和6.1kJ/m2.     

<Emphasis Type="BoldItalic">In-situ</Emphasis> microfibrillar PP–PA6 composites: rheological,morphological and mechanical properties

In this study, the rheology, morphology and mechanical properties of microfibrillar composites based on polypropylene reinforced with polyamide 6 (PA6) fibres have been investigated. Influence of different factors such as the PA6 composition and drawing ratio on the output of the extruder, and the compatibilizer composition on the properties of these composites, were investigated. The results of rheometric mechanical spectrometer rheological measurements and melt flow index (MFI) showed that the storage modulus, loss modulus and complex viscosity of the microfibrillar composites are directly related to the composition of PA6. It was also shown that the presence of compatibilizer was the main factor that led to decrease of some properties including the storage modulus, loss modulus and complex viscosity and increase in the MFI. The results of mechanical tests on samples prepared with different drawing ratios showed that by increasing the drawing ratio from 3 to 5, the mechanical properties increase, while increasing draw ratio from 5 to 8 reduces the mechanical properties. With the increase in the composition of the polyamide phase, the tensile strength of microfibrillar composite compatible with polypropylene-grafted-maleic anhydride initially increased; however, the tensile strength decreased with a high composition of polyamide phase. Scanning electron microscope images also revealed that the presence of the compatibilizer in the microfibrillar composites leads to decrease in the number of undeformed drops, while it reduces the micro-fibres diameter, which greatly improved the final properties of the composites.     

The effect of fibrous reinforcement on optical and impact performance of fibre-reinforced transparent glass composites

Fire-resistant laminated glass composite containing intumescent silicate as an interlayer between two glass sheets is a widely used transparent building material. To improve the impact and other mechanical properties of this composite structure, a transparent silicate matrix has been reinforced with alkali- and UV-resistant synthetic (polypropylene, polyamide 66, glass) and metallic (steel) fibres as of nonwoven webs or woven meshes. The refractive indices (RIs) of the fibres and the matrices were measured and the transparency of the laminated composites depended upon fibre RI as well as reinforcement structure. All fibres were successful in significantly enhancing impact properties of laminated glass composites with alkali-resistant glass fibres showing the best performance.     

The effects of Clay on fire performance and thermal mechanical properties of woven glass fibre reinforced polyamide 6 nanocomposites

The effects of small amount of organically modified Clay (Clay) in polyamide 6 (PA6) on fire performance and thermal mechanical properties of Clay/PA6/woven glass fibres (GF) laminates are investigated by cone calorimeter test, dynamic mechanical thermal analysis (DMTA), and heat distort temperature (HDT) measurement. The mechanical properties, such as tensile and flexural properties of Clay/PA6 composites and Clay/PA6/GF laminates were also measured. Up to 3 wt.% Clay in a Clay/PA6/GF laminate with fibre volume fraction of 30 vol.% delayed the ignition time and peak heat release rate (PHRR) time by 55% and 118%, respectively, even though the value of the PHRR or the HDT was not significantly affected. 2 wt.% Clay increased flexural modulus and strength of the Clay/PA6/GF laminate by 10% and 16%, respectively, but more Clay did not increase the mechanical properties accordingly. Small amount of Clay does not affect glass fibre dominated properties, such as HDT, but do affect matrix dominated properties, and significantly affect the fire performance in terms of delaying ignition time and PHRR time. Optimization of laminate making process could benefit from additions of more Clay, therefore further improve fire performance and enhance mechanical properties.