几种插层剂改性的MMT／PA66纳米材料的性能

用多种插层剂合成了有机改性蒙脱土（MMT），将PA66与改性MMT共混制成纳米材料，表征了其结构和力学性能。5％的纳米MMT1631能将PA66的冲击强度提高近50％，3％的MMT1827能将PA66的断裂伸长率提高52．5％，观察到MMT／PA66纳米塑料的无熔滴等阻燃特性，总结了不断插层剂改性MMT／PA66纳米材料的特点，发现MMT与常规阻燃剂之间有力学协效作用和阻燃协效作用，能提高PA66的力学性能和阻燃性能。     

EVA／LLDPE／Mg（OH）2／纳米蒙脱土复合材料的研究

合成了有机改性蒙脱土（MMT），用线型低密度聚乙烯、乙烯-醋酸乙烯共聚物作为无卤电缆材料主体，将LLDPE和EVA分别与改性MMT，Mg（OH）2主阻燃剂共混制成纳米复合材料，发现改性MMT与阻燃剂之间有力学和阻燃协效作用，能同时提高塑料的力学和阻燃性能。     

酚醛树脂改性纳米蒙脱土填充PA6的制备及性能研究

分别利用经十八烷基三甲基氯化铵(OTAC)、酚醛树脂(PF)表面改性的纳米蒙脱土(MMT)填充聚酰胺(PA)6,研究了不同表面改性剂及其用量对PA6的力学性能、热性能和吸水性的影响。结果表明,经OTAC改性的纳米MMT和经PF改性的纳米MMT对PA6的热性能改善效果有限,但有利于提高PA6的刚性和降低吸水性。PF改性纳米MMT对PA6的改性效果优于OTAC改性纳米MMT,当PF改性纳米MMT的质量分数为3%时,材料的拉伸强度、弯曲强度和维卡软化温度分别比纯PA6提高了12.3%、58.8%和2%,吸水率降低0.5%。     

EVA/LLDPE/Mg(OH)_2/纳米蒙脱土复合材料的研究

合成了有机改性蒙脱土(MMT),用线型低密度聚乙烯、乙烯-醋酸乙烯共聚物作为无卤电缆材料主体,将LLDPE和EVA分别与改性MMT,Mg(OH)2主阻燃剂共混制成纳米复合材料,发现改性MMT与阻燃剂之间有力学和阻燃协效作用,能同时提高塑料的力学和阻燃性能。     

蒙脱土(MMT)/PA纳米复合材料的制备与性能研究

用熔融插层法制备 MMT/PA纳米复合材料 ,先合成有机改性蒙脱土 ,再将 PA6和 PA66分别与改性 MMT共混制成纳米复合材料。表征了其结构和力学性能 ,观察了 MMT/PA6和 MMT/PA66纳米复合材料的阻燃特性。发现纳米 MMT也能将 PA66的冲击强度提高近 50 % ,并能提高 PA6的 LOI,与其他阻燃剂起协同效应     

纳米级三氧化二锑与MCA协同阻燃性能对PA6的影响

采用了未经表面改性和经硅烷偶联剂进行表面改性的等离子法纳米级三氧化二锑（Sb2O3）,研究了三聚氰胺氰尿酸盐（MCA）与纳米级Sb2O3的不同配比对PA6的阻燃效应和力学性能的影响。结果表明：纳米级Sb2O3与MCA的质量比为1．5：8．5时,协效效果较好,氧指数达33％以上,拉伸强度达到73．2MPa,冲击强度变化不大。热重分析显示：协效阻燃体系对尼龙6（PA6）体系的热分解特征有一定的影响。     

EVA／APP／PER／MEL／纳米蒙脱土复合材料的研究

通过制备有机改性蒙脱土(MMT),共混改性乙烯-醋酸乙烯共聚物为主体的无卤膨胀阻燃电缆材料,发现改性MMT与聚磷酸铵(APP)/季戊四醇(PER)/三聚氰胺(MEL)三元膨胀阻燃剂(IFR)之间有力学和阻燃协效作用,能同时提高塑料的力学和阻燃性能。     

玻纤增强阻燃PA6复合材料的制备与研究

从磷-氮系阻燃剂、阻燃剂类型、协效阻燃剂三个方面制备和研究了高冲击强度、高阻燃性能的玻纤增强阻燃尼龙6(PA6)复合材料。结果表明:三种方法都可以达到阻燃V-0;在溴-锑阻燃基础上,添加磷-氮系阻燃剂,可以提高玻纤增强阻燃PA6的阻燃性,但是会降低力学性能;红磷阻燃制备的复合材料的冲击性能最好;溴-锑阻燃制备的复合材料的拉伸强度和弯曲强度最高,冲击性能最低;有机次膦酸盐制备的复合材料的拉伸强度和弯曲强度最低,冲击性能适中;协效阻燃剂可以降低溴-锑的含量,降低材料成本,阻燃性能保持不变,拉伸强度和弯曲强度略有下降,冲击性能略有上升。得出如下结论:红磷阻燃剂质量分数是6%,以及F2400∶三氧化二锑∶协效阻燃剂质量分数比=17∶5∶2时,玻纤增强阻燃尼龙6复合材料的冲击性能最好,阻燃性达到UL94(1.6 mm)V-0。     

三聚氰胺聚磷酸盐/硼酚醛协效体系阻燃PA66/GF复合材料的研究

采用氮磷型阻燃剂三聚氰胺聚磷酸盐(MPP)与硼改性酚醛树脂(BPF)组成的复合阻燃体系对玻纤(GF)增强尼龙66( PA66)复合材料进行阻燃,获得了阻燃性能优异、力学性能良好的增强复合材料,研究了协效阻燃剂BPF/MPP配比、BPF/MPP用量及GF用量对阻燃复合材料阻燃性能的影响,采用微型燃烧量热和质量保持率分析方法研究了阻燃复合材料的燃烧及成炭行为,对复合阻燃剂的协效机理进行了讨论.结果表明,当BPF在BPF/MPP中的质量分数为15％时,添加25％ BPF/MPP复合阻燃剂可使20％ GF增强PA66复合材料达到V-0( 1.6 mm)阻燃级别,极限氧指数增加至25.3％,拉伸强度、弯曲强度、缺口冲击强度分别为116 MPa,132 MPa,7.1 kJ/m2.该复合材料可满足高性能无卤阻燃的使用要求.     

尼龙6/纳米三氧化二锑性能的研究

采用等离子体法生产的纳米三氧化二锑制备阻燃尼龙6(PA6),并通过氧指数(LOI)、锥形量热及TEM等检测,研究了纳米三氧化二锑对PA6阻燃性能和力学性能的影响。结果表明,当纳米三氧化二锑质量分数为6%时,LOI可达30%;热释放速率峰值减小了60 kW/m2,且达到峰值的时间较纯PA6延迟了约2 min;硅烷偶联剂KH-550改性的纳米三氧化二锑在PA6中的弥散度比未改性的高。与未改性纳米三氧化二锑相比,经过表面改性后,材料的拉伸强度提高60.7%、缺口冲击强度提高14.8%、弯曲强度提高36.8%、弯曲模量提高39.6%。     

Chemical effects of cationic surfactant and anionic surfactant used in organically modified montmorillonites on degradation and fire retardancy of polyamide 12 nanocomposites

Three kinds of organically modified Na⁺-montmorillonites (OMMTs), including two kinds of octadecylammonium modified montmorillonite with different contents of octadecylammonium and a kind of sodium dodecylsulfonate (SDSo) modified montmorillonite, were used to prepare polyamide 12 (PA12)/OMMT nanocomposites. Effects of the modifiers on degradation and fire retardancy of PA12/OMMT nanocomposites were investigated. Acid sites formed in cationic surfactant modified MMT via Hoffman decomposition could accelerate degradation of PA12 at high temperature. However, catalytic effect of the acid sites on carbonization of the degradation products promoted char barrier formation, which reduced heat release rate (HRR). Higher content of cationic surfactant in OMMT is beneficial to fire retardancy of PA12 nanocomposites and the dispersion states of OMMT have assistant effects. In contrast, Na⁺-montmorillonite (Na-MMT) and anionic surfactant modified MMT (a-MMT) could not form acid sites on the MMT layers; in this case, fire retardancy of PA12/Na-MMT appears to have no improvement and PA12/a-MMT appears to have limited improvement.     

Using PA6 as a charring agent in intumescent polypropylene formulations based on carboxylated polypropylene compatibilizer and nano‐montmorillonite synergistic agent

The intumescent fire retardant polypropylene (IFP/PP) filled with ammonium polyphosphate (APP), melamine (M), and PA6 (charring agent) is discussed. Intumescing degree (ID) and the char yield were determined. Only when the three main components of IFR coexist at appropriate proportions, it has optimal ID and higher char yield. The appropriate proportion is PA6 : APP : M = 10 : 10 : 5. A new compatibilizer, carboxylated polypropylene (EPP), was added to PP/PA‐6 blend. Flow tests indicated that the apparent viscosity increased with the addition of EPP, thermal characterization suggested that EPP has reacted with PA6, PA6‐g‐EPP cocrystallized with PA6, and EPP‐g‐PA6 cocrystallized with PP; SEM micrographs illustrated that the presence of EPP improved the compatibility of PP and PA6. All the investigations showed that EPP was an excellent compatibilizer, and it was a true coupling agent for PP/PA6 blends. Using PA6 as a charring agent resulted in the IFR/PP dripping, which deteriorated the flammability properties. The addition of nano‐montmorillonite (nano‐MMT) as a synergistic agent of IFR enabled to overcome the shortcoming. The tensile test testified that the addition of nano‐MMT enhanced the mechanical strength by 44.3%. SEM showed that nano‐MMT improved the compatibility of the composites. It was concluded that the intumescent system with nano‐MMT was an effective flame retardant in improving combustion properties of polypropylene. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 101: 739–746, 2006     

Flame‐retarding mechanism of organically modified montmorillonite and phosphorous‐Nitrogen flame retardants for the preparation of a halogen‐free,flame‐retarding thermoplastic poly(ester ether) elastomer

In this study, thermoplastic poly(ester ether) elastomer (TPEE) nanocomposites with phosphorus–nitrogen (P–N) flame retardants and montmorillonite (MMT) were prepared by melt blending. The fire resistance of the nanocomposites was analyzed by limiting oxygen index (LOI) and vertical burning (UL 94) tests. The results show that the addition of the P–N flame retardants increased the LOI of the material from 17.3 to 27%. However, TPEE containing P–N flame retardants only obtained a UL 94 V‐2 ranking; this resulted in a flame dripping phenomenon. On the other hand, TPEE containing the P–N flame retardant and organically modified montmorillonite (o‐MMT) achieved better thermal stability and good flame retardancy; this was ascribed to its partially intercalated structure. The synergistic effect and synergism were investigated by Fourier transform infrared spectroscopy and thermogravimetry. The introduction of o‐MMT decreased the inhibition action of the P–N flame retardant and increased the amount of residues. The catalytic decomposition effect of MMT and the barrier effect of the layer silicates are discussed in this article. The residues after heating in the muffle furnace were analyzed by scanning electron microscopy, energy‐dispersive X‐ray spectroscopy and laser Raman spectroscopy. It was shown that the intercalated layer silicate structure facilitated the crosslinking interaction and promoted the formation of additional carbonaceous char residues in the formation of the compact, dense, folded‐structure surface char. The combination of the P–N flame retardant and o‐MMT in TPEE resulted in a better thermal stability and fire resistance because of the synergistic effect of the mixture. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41094.     

硼酸锌协效二乙基次膦酸铝阻燃PA6

采用硼酸锌(ZB)与二乙基次膦酸铝(ADP)协同阻燃聚酰胺6(PA6).对其阻燃性能和力学性能进行了探讨,并运用垂直燃烧、极限氧指数、锥形量热、热失重分析、扫描电子显微镜以及拉曼光谱对阻燃机理进行了探究.结果表明,ZB作为协效剂,与ADP的协同阻燃效果显著;当在PA6中添加1.5％(质量分数,下同)ZB和8.5％ADP...     

硅锡协同阻燃尼龙6

采用氯化亚锡(SnCl2)/聚氨丙基苯基倍半硅氧烷(PAPSQ)复合阻燃剂阻燃改性尼龙6(PA6)。测定了阻燃PA6的氧指数(LOI),利用锥形量热仪测定了阻燃PA6的释热速率、总释热量、有效燃烧热等多种阻燃参数,并用扫描电镜(SEM)观察了阻燃PA6残炭的形貌。实验表明,当SnCl2用量为4%,PAPSQ用量为1%时,PA6的LOI为31%,PA6的释热速率、总释热量和有效燃烧热均明显下降,PAPSQ对SnCl2有协同阻燃效果。     

Enhanced mechanical properties and fire retardancy of polyamide 6 nanocomposites based on interdigitated crystalline montmorillonite–melamine cyanurate

Polyamide 6 (PA6)–montmorillonite (MMT)–melamine cyanurate (MCA) nanocomposites were prepared by the incorporation of interdigitated crystalline MMT–MCA. Their morphologies were assessed by X‐ray diffraction, scanning electron microscopy, transmission electron microscopy, thermal stability measurement by thermogravimetric analysis, mechanical properties measurement by tensile tests, and fire retardancy measurement by limiting oxygen index testing and vertical burning testing (UL‐94). The results indicate that MMT–MCA was homogeneously nanodispersed in PA6. Compared with PA6–MCA, the PA6–MMT–MCA nanocomposites showed enhanced thermal stability. The mechanical properties and fire retardancy show that the PA6–MMT–MCA nanocomposites with 5 wt % total loading of MMT–MCA reached UL‐94 V‐2 rating (3.2 mm) and significantly increased the tensile strength of PA6 up to 24.8 % with only 1 wt % MMT in PA6. Through the control the weight ratio of MMT and MCA in MMT–MCA, the Young's modulus of PA6 could be adjusted in a very wide range (300–1100 MPa) because of the dual role of the rigid MMT and nonrigid MCA layers. The reinforced mechanism of the mechanical properties was also investigated. Consequently, the PA6–MMT–MCA nanocomposites with a good nanodispersing ability, improved thermal stability, excellent mechanical properties, and good flame retardancy were obtained and could provide broad prospects for wider applications for PA6 materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46039.     

A P/N synergistic flame retardant containing flexible nitrile group for enhancing the mechanical properties and fire safety of epoxy resins

To further enhance the fire safety of epoxy resins, a phosphorus–nitrogen synergistic flame retardant (DPVHD) with a flexible chain segment and a nitrile group was synthesized. In addition to the traditional flame retardant elements P and N, the flame retardancy of the epoxy composites is further enhanced by the cross-linking effect of the nitrile groups introduced to form an interpenetrating network with the epoxy matrix. The results showed that the sample with 10 wt% DPVHD-10/EP had a LOI of 32.3% and passed the UL-94 V-0 rating, with PHRR and THR reduced by 15.4% and 47%, respectively, compared to pure EP. It is worth noting that the introduction of flexible chain segments improves the flexural properties of the epoxy resin matrix. Compared with pure epoxy, the flexural properties of epoxy-cured compounds with DPVHD addition show a rising trend with the increase of flame-retardant additive. And the rise of DPVHD-10/EP reaches 33.6%, which greatly reduces the negative effect of flame-retardant additives on the mechanical properties of the epoxy resin matrix. This work therefore provides new ideas for exploiting the advantages of phosphorus-nitrogen synergy and nitrile-based cross-linking for flame retardancy in epoxy resins.     

尼龙6/有机蒙脱土阻燃复合材料的结构与性能

将尼龙6、有机蒙脱土和阻燃剂（氢氧化镁、氨基硅油、十溴联苯醚和三氧化二锑、三聚氰胺焦磷酸盐、三聚氰胺磷酸盐）通过熔融插层法直接制备了尼龙6／有机蒙脱土阻燃复合材料。通过X射线衍射（XRD）、力学性能测试、极限氧指数（LOI）测试研究了蒙脱土在复合材料内的分散、复合材料的力学性能以及阻燃性能。结果表明：氨基硅油与有机蒙脱土具有阻燃协同效应,当氨基硅油和有机蒙脱土质量分数分别为2％和5％时,复合材料的LOI高达34％。氢氧化镁、氨基硅油与有机蒙脱土三者具有极强的阻燃协同效应,当氢氧化镁用量分别为30％、40％、50％时,阻燃复合材料的LOI分别为63％、60％、70％。