核壳型纳米粒子填充PP-EVA及阻燃材料的动态燃烧行为

利用锥形量热仪(CONE)和热重分析(TGA),并结合极限氧指数(LOI)和UL-94垂直燃烧测试方法对核(PSt/OMMT)-壳(PBA)结构纳米复合粒子(CSN)填充聚丙烯(PP)-乙烯-醋酸乙烯酯共聚物(EVA)复合材料及加入无卤复配阻燃剂制备的PP-EVA/CSN/聚磷酸铵(APP)/层状氢氧化镁铝(LDH)复合阻燃材料的阻燃性能及热降解行为进行了研究。结果表明,添加10%(wt)CSN可以提高PP-EVA复合材料的阻燃性能,且PP-EVA复合体系燃烧时的热释放速率、有效燃烧热减少,热稳定性增强。CSN与APP/LDH产生阻燃协同作用,使复合阻燃材料的阻燃性能、热稳定性能进一步提高。     

有机蒙脱土/天然橡胶纳米复合材料的阻燃性能研究

采用机械混炼插层法制备有机蒙脱土/天然橡胶(TMT/NR)纳米复合材料.使用X-射线衍射(XRD)和红外表征了有机蒙脱土的结构特性,并用锥形量热仪测试了纳米复合材料的燃烧性能.结果表明,有机蒙脱土/NR纳米复合材料的热释放速率(HRR)、生烟速率(SPR)等较纯天然橡胶、未改性蒙脱土/NR复合材料均所有降低,表现出较好的阻燃性能.通过对纳米复合材料的燃烧性能和燃烧残余物分析,探讨了该体系的阻燃机理.     

PP/EVA/OMMT纳米复合材料及其阻燃材料的动态燃烧行为

利用锥形量热仪(CONE)在35kW/m2热辐照条件下,并结合极限氧指数(LOI)和UL-94垂直燃烧测试方法对聚丙烯(PP)/乙烯-醋酸乙烯酯共聚物(EVA)/有机蒙脱土(OMMT)纳米复合材料和加入无卤复配阻燃剂制备的PP/EVA/OMMT/氢氧化铝(ATH)/三氧化二锑(AO)纳米复合阻燃材料的热释放速率、烟释放及材料在燃烧时的质量损失行为进行了研究。结果表明,添加5%(质量分数)OMMT可以提高PP/EVA复合材料的阻燃性能,燃烧时的热释放速率、质量损失率以及烟释放量减少,且OMMT与无卤复配阻燃剂之间可产生阻燃协同作用,使纳米复合阻燃材料的阻燃性能、热稳定性和抑烟性进一步增强。     

改性酚醛成炭剂的制备及其在氢氧化镁/聚酰胺6阻燃体系中的协效阻燃作用

氢氧化镁(MH)是一种重要环保型阻燃剂,针对MH阻燃效率低,添加量大,与树脂相容性差的特点,研制了硼改性酚醛基成炭剂(BPF)用于增强MH的凝聚相阻燃作用,以提高MH的阻燃效率.用XRD、红外、核磁等手段表征了BPF的化学结构.TGA研究表明BPF成炭性优异,750℃时残炭高达61%.阻燃PA6体系中,BPF与MH有显著的协效作用,材料能通过UL94-1.6 mm V0级别.BPF的阻燃增效机理分析表明,BPF燃烧时生成的B2O3可在燃烧材料表面富集形成玻璃态的有效阻隔层,使材料自熄.此外,BPF能显著提高材料加工流动性,具有较好增塑、润滑作用.BPF不会恶化材料力学性能,阻燃材料综合性能优良.     

多层次炭结构对膨胀阻燃聚丙烯性能的调控作用研究

将具有封闭空心结构的酚醛微球(HPMs)引入到聚丙烯/膨胀阻燃剂(PP/IFR)体系,燃烧时一方面依托PP/IFR形成膨胀多孔炭,另一方面通过HPMs形成空心炭微球,嵌入到前面多孔炭的骨架中,形成具有多层次孔的炭结构,从而调控膨胀炭层,进而调节材料的阻燃性能.通过极限氧指数(LOI)、垂直燃烧(UL-94)等研究了材料的阻燃性能;通过热失重分析(TGA)测试其热稳定性;采用红外热成像仪监测燃烧过程材料的表面温度,用扫描电镜(SEM)观察IFR、HPMs在基体中的分散行为及炭层结构.结果表明,少量HPMs在聚合物中分散得比较均匀.HPMs调控了膨胀炭层,使PP/IFR形成了表层炭致密,内层具有多层次孔的炭结构.这种优质的炭结构可以使样品表面温度迅速降低,从而有效提高PP/IFR体系的阻燃效率,使得PP在添加18 wt%IFR和1 wt%HPMs就可以通过UL-94 V0级别.     

OMMT-NC-膨胀型阻燃剂三元协同阻燃LLDPE的效果

采用有机蒙脱土(OMMT)和碳酸镍(NC)为阻燃协效剂,与膨胀型阻燃剂(IFR)三元体系协同阻燃线性低密度聚乙烯(LLDPE).采用热重分析(TGA)、氧指数(LOI)测试、UL-94燃烧测试和锥形量热测试(CONE)研究了LLDPE阻燃体系的热稳定性和燃烧性能;采用红外光谱分析(FT-IR)、数码相机和扫描电子显微镜(SEM)对燃烧残余物的结构和形貌进行了分析.结果表明:固定mnLLDPE/mIFR=7/3,当moMMT/m(LLDPE+IFR)=0.04时,阻燃体系的LOI为31.5％,通过UL-94 V-0级测试,LLDPE-IFR-OMMT的残炭率为15.09％,最大热释放速率(PHRR)相比于纯LLDPE降低了50％;向LLDPE-IFR-OMMT体系中添加NC,少量的NC就能显著增加体系的阻燃性能,当mNC/m(LLDPE+IFR)=0.02时,阻燃体系的LOI为32.7％,LLDPE-IFR-OMMT-NC的残炭率达到19.04％,PHRR相比于纯LLDPE降低了57％.OMMT和NC的加入能催化LLDPE-IFR成炭,形成致密的炭层,增加炭层的强度,从而提高复合材料的阻燃性能.     

纳米LDHs在膨胀阻燃体系中的阻燃机理

采用程序升温装置(TPO)研究了纳米LDHs在膨胀阻燃体系中的阻燃机理. 分别考察了复合膨胀阻燃剂中的纳米LDHs在氧气中与氮气中的作用, 得出了纳米LDHs对富碳化合物的催化氧化作用以及对膨胀层炭化、发泡的贡献. 在氧气存在下燃烧时, 纳米LDHs具有促使富碳化合物催化氧化的作用; 在无氧条件下纳米LDHs可使富碳化合物残碳率提高, 提高碳的石墨化程度以及成碳质量, 并在一定程度上具有促进热融的富碳体系膨胀发泡的作用.     

双酚A双(二苯基)磷酸酯对环氧树脂的阻燃性能

采用双酚A双(二苯基)磷酸酯(BDP)、有机改性蒙脱土(OMMT)和环氧树脂(EP),分别制备了阻燃环氧树脂(BDP-EP)和阻燃纳米材料(BDP-OMMT-EP).利用氧指数、水平垂直燃烧、热重分析以及锥形量热等技术探讨了阻燃材料的阻燃性能和阻燃机理.实验结果证明,BDP-EP和BDP-OMMT-EP的最大热释放速率和平均热释放速率等参数都降低了,但是BDP的阻燃效果优于BDP-OMMT,即BDP和OMMT没有协同阻燃作用.     

耐高温杂化阻燃剂/改性红磷阻燃半芳香尼龙的研究

将自制的耐高温勃姆石@苯基次膦酸铝杂化阻燃剂(BM@Al-PPi)与市售改性红磷(MRP)复配制得一种可用于半芳香尼龙PA6T/DT(HTN)的耐高温高效阻燃体系.保持阻燃剂15 wt%的总添加量不变时,MRP的添加量仅为5 wt%即可赋予HTN垂直燃烧V-0级别,极限氧指数为29.8%.锥形量热测试及其燃烧残余物研究表明,MRP阻燃HTN材料以气相阻燃作用为主,抑制热释放效果不佳且烟释放明显增加;而BM@Al-PPi的凝聚相交联成炭作用可同时抑制热释放与烟释放.结合裂解气相色谱质谱联用(Py-GC-MS)分析,给出了HTN/BM@Al-PPi/MRP体系的阻燃机理.BM@Al-PPi与MRP结合使得残炭质量显著提高,同时兼具气相作用,达到了较好的阻燃效果.     

纳米二氧化硅表面接枝9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物以及对聚甲基丙烯酸甲酯复合材料阻燃性能和透明性的影响

聚甲基丙烯酸甲酯(PMMA)是一种重要的透明高分子材料,但是PMMA的易燃性限制了其应用。 本工作在纳米二氧化硅表面接枝含磷阻燃剂9,10-二氢-9-氧杂-10-磷杂菲-10-氧化物(DOPO),并用于聚甲基丙烯酸甲酯(PMMA)的改性。 极限氧指数(LOI)、垂直燃烧(UL-94)和锥形量热(CCT)测试结果表明,制备的PMMA复合材料的阻燃性能大幅度提高,这主要归因于纳米粒子和含磷阻燃剂的协同阻燃作用,形成致密的炭保护层结构。 同时,二氧化硅接枝DOPO的加入可以保持PMMA良好的透明性,这有利于材料在光学透明性要求较高的领域的应用。     

Flame retarded polymer nanocomposites: Development,trend and future perspective

Polymer nanocomposites are a new class of flame retarded materials which have attracted much attention and considered as a revolutionary new flame retardant approach.A very small amount of nano flame retardants (normally < 5 wt%) can significantly reduce the heat release rate (HRR) and smoke emission (SEA) during the combustion of polymer materials.Moreover,the addition of nano flame retardants can also improve the mechanical properties of polymer materials compared with the deterioration of traditional fla...     

磷系阻燃剂阻燃聚碳酸酯研究进展*

磷系阻燃剂具有阻燃效率高、低烟、低毒、与基质材料相容性好等优点,在阻燃高分子材料领域得到广泛应用。本文介绍了磷系阻燃剂的分类及阻燃机理,综述了近年来磷酸酯阻燃剂、膦酸酯阻燃剂、DOPO磷杂菲类阻燃剂、磷腈类阻燃剂和无机磷阻燃剂在阻燃聚碳酸酯领域的研究进展,为新型磷系阻燃剂的研发提供参考。     

Recent Progress in Two-dimensional Nanomaterials Following Graphene for Improving Fire Safety of Polymer (Nano)composites

The high fire safety of polymer nanocomposites is being pursued by research institutions around the world. In addition to intrinsic flame retardancy strategy, the additive-type flame retardants have attracted increasing attention due to low commercial cost and easy fabrication craft. However, traditional additive-type flame retardants usually need high addition amount to achieve a desirable effect, which causes many side-effects on the overall performance of polymer materials, such as deteriorated mechanical property and processability. At present, two-dimensional(2 D) nanomaterials have also been applied to reduce the fire hazards of polymer(nano)composites with the coupling of barrier function and catalysis as well as carbonization effect. Even though most research work mainly focus on graphene-based flame retardants, more emerging two-dimensional nanomaterials are taking away research attention, due to their complementary and unique properties, mainly including hexagonal boron nitride(h-BN), molybdenum disulfide(MoS_2), metal organic frameworks(MOF), carbon nitride(CN),titanium carbide(MXene) and black phosphorene(BP). In this review, except for graphene, the flame retardant mechanism involving different layered nanomaterials are also reviewed. Meanwhile, the functionalization method and flame retardancy effect of different layered nanomaterials are emphatically discussed for offering an effective reference to solve the fire hazards of polymer materials. Moreover, this work objectively evaluates the practical significance of polymer/layered nanomaterials composites for industrial application.     

Polymer additive analysis by pyrolysis-gas chromatography. II. Flame retardants

Flame retardants are widely used in thermoplastic polymers for household and transportation applications. Flame retardants as well as most of the other additives in the polymer can be qualitatively analyzed by pyrolysis-gas chromatography (Py-GC) simultaneously with the polymer composition. The key to successful analysis of flame retardants not only requires a thorough knowledge of the various types of flame retardants but also necessitates an understanding of the parent polymer and its targeted applications. In this study, several flame retardants in different polymer matrices have been studied to demonstrate the utility of Py-GC for the analysis of flame retardants. The advantages of Py-GC for flame retardants analysis have also been discussed.     

A review on flame retardant technology in China. Part I: development of flame retardants

This paper provides an insight into some developments in flame retardants for different polymeric materials in China, primarily based on the publications that have appeared in the last 15 years. It focuses on the following aspects: halogen‐containing flame retardants, inorganic flame retardants (e.g. metal oxides and hydroxides, silicon‐containing materials, ammonium polyphosphate, red phosphorus, and expandable graphite), and organic flame retardants (e.g. aliphatic and aromatic phosphonates, nitrogen‐containing organics, and multi‐element organics). The inherently flame‐retardant polymer systems are also reviewed. The exploration of the novel flame retardants and flame‐retardant systems provides a powerful basis for the construction of flame‐retardant technologies and industrial applications in China. Copyright © 2009 John Wiley & Sons, Ltd.     

反应性挤出加工制备无卤阻燃高分子材料

聚合物反应性加工集聚合物加工与化学反应为一体,以聚合物加工装置为反应器,通过聚合物加工过程中的化学反应形成新物质和新结构,实现高分子材料的高性能化和功能化,是高分子材料科学的研究前沿之一.本文简要介绍了我们研究小组近年来采用反应性挤出加工制备高性能无卤阻燃高分子材料方面的研究进展.利用反应性挤出加工剪切力强、温度可控以及易于传质传热的特点实现了常规方法难以合成的高黏阻燃剂三聚氰胺磷酸盐季戊四醇酯（MPP）和三聚氰胺氰尿酸（MCA）的高效合成,制备了综合性能优良的聚丙烯/MPP、尼龙6/MCA等无卤阻燃高分子材料.研究所涉及的化学和物理方法,为聚合物无卤阻燃提供了高效、经济、环保和易于工业化的新技术,并拓宽了聚合物反应性加工的应用领域.     

(Photo)oxidative degradation and stabilization of flame retarded polymers

Flame retarded polymer formulations are mainly used in long-term applications whereas antioxidants, light stabilizers and co-additives provide the requested lifetime of plastic materials. However many flame retardants influence the oxidative and photooxidative stability of polymers often in a negative way resulting in early failure and loss in value. Moreover insufficient (photo)oxidative stability of the flame retardant itself may reduce the flame retardance performance over time. Therefore, there is a need to develop adjusted stabilizer systems considering the type of flame retardant, the polymer substrate and the intended application. Therefore, the influence of flame retardants on the (photo)oxidative stability of selected polymers is reviewed and strategies to extend the lifetime of flame retarded polymers are provided. In addition, the specific requirements of the stabilization of nanocomposites as potential flame retardant components are covered.     

硅橡胶复合材料阻燃研究进展

将功能填料引进到硅橡胶及其复合材料中可以获得特定功能的硅橡胶复合材料,已经成为近些年研究热点。目前阻燃剂种类繁多,但是性能比较单一,这已经不能满足人们的需要。人们在关注硅橡胶复合材料阻燃性能的同时,也考虑与其它性能兼备以及成本等问题。因此,本文综述了铂化合物、磷系阻燃剂、阻燃涂层、阻燃填料和微胶囊化阻燃剂等阻燃体系下硅橡胶复合材料的阻燃研究现状,总结了不同阻燃剂的阻燃机理,并且给出了其今后的改进方法,最后对硅橡胶复合材料阻燃研究的发展做了展望。     

Fire behavior of flame retarded unsaturated polyester resin with high nitrogen content additives

The novel flame retarded unsaturated polyester resins have been developed and prepared by introduction of high nitrogen content additives into the polymer matrix in order to verify their effectiveness in the formation of swollen carbonaceous char inhibiting the burning process of the polymer. The intumescent flame retardants (IFRs) based on mixture or metal complex were developed and characterized by particle size distribution, Fourier-transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), powder X-ray diffraction (XRD), elemental analysis (CHN) and thermogravimetric analysis (TGA). The evaluation of the efficiency of IFRs addition on the flammability and smoke emission of the unsaturated polyester resins (UP) was carried out using the fire hazard (UL-94), limiting oxygen index (LOI) and cone calorimeter (CC) tests, as well as smoke density chamber tests. The volatile compounds evolved during the burning of materials were determined using a steady state tube furnace and a gas chromatograph with mass spectrometer. Furthermore, the prepared materials were subjected to differential scanning calorimetry (DSC), thermogravimetric analysis and water resistance tests. The mechanical properties of the materials were investigated using Shore D hardness and dynamic mechanical thermal analysis (DMA). The structural evaluation of the manufactured materials and samples after the cone calorimetry tests was carried out using scanning electron microscopy (SEM). It was found that the incorporation of new intumescent flame retardants led to the formation of carbonaceous char layers’ inhibiting the decomposition process and limiting the smoke emission. The most promising results were obtained for the resin containing complex designated as ZN3AT, for which the highest reduction in maximum values of heat release rate (419 kW/m²) compared to unmodified polymer (792 kW/m²) were recorded. Apart from that, the prepared intumescent flame retardants affect the cross-linking process as well as the thermal and mechanical properties of the UP.     

Effect of surfactant types on particle size and morphology of flame-retardant zinc borate powder

Zinc borate is a boron-containing chemical material that is used to increase the flame retardancy of polymeric materials, dyes, cables, fabrics, carpets, and the internal parts of automobiles and planes. Commercially used zinc borate, which has the formula of 2ZnO·3B ₂ O ₃ ·7H ₂ O, has a particle size between 10 and 20 μm. However, recent studies have shown that nanosized flame retardants have more superior flame retardancy and less negative effects on mechanical properties than microsized flame retardants. Nanosized flame retardants disperse more homogeneously and even low quantities are sufficient to provide high flame resistance. In this study, nano zinc borate powder was synthesized by a wet chemical method and the effects of nonionic, anionic, and cationic surfactants on the particle size and morphology of the zinc borate particles were investigated. Chemical purity and physical structures of the synthesized zinc borate powder were analyzed by XRD, FTIR, TG-DTA, TEM, and Zetasizer. The analysis results showed that the zinc borate powder had a chemical formula of 2ZnO·3B ₂ O ₃ ·7H ₂ O. TEM and Zetasizer results indicated that the nano zinc borate powder, which had nanoscale particle size distribution with needle- and flake-like structures, was synthesized using nonionic, anionic, and cationic surfactants.