聚合物/层状硅酸盐纳米复合材料的阻燃性能研究进展

聚合物/层状硅酸盐纳米复合材料作为一种新型阻燃材料,具有阻燃效率高、添加量低、无卤低毒、环境友好等优点,是当今聚合物阻燃无卤改性研究领域的热点之一。本文简述了聚合物-层状硅酸盐体系、阻燃剂-层状硅酸盐阻燃体系改性聚合物的研究进展,以及功能化层状硅酸盐新型阻燃剂的制备、阻燃性能、阻燃机理以及在阻燃领域的应用。     

硅系阻燃剂研究进展

综述了近年来有关硅系阻燃剂的结构与性能以及阻燃改性等方面的研究进展。介绍了无机硅系阻燃剂 (包括聚合物/层状硅酸盐以及聚合物/二氧化硅纳米复合材料)的热稳定性和阻燃性能。侧重论述了有机硅系阻燃剂(包括本质阻燃聚合物、笼状倍半硅氧烷及其改性聚合物)的热稳定性、阻燃性能和阻燃机理。     

有机聚合物／无机化合物纳米复合阻燃材料研究进展

综述了有机聚合物／无机化合物纳米复合阻燃材料的研究和应用现状。阐述的纳米复合阻燃材料包括有机聚合物／层状硅酸盐纳米复合材料、有机聚合物／碳纳米管纳米复合材料、有机聚合物／二氧化硅纳米复合材料、有机聚合物／石墨纳米复合材料等。与传统无机阻燃剂填充阻燃材料相比,这类新型纳米复合阻燃材料的填料与基体的亲合性、基体的物理力学性能和阻燃性能等均得到改善。     

硅系阻燃剂研究进展

从添加型硅系阻燃剂、含硅本质阻燃高聚物、聚合物／层状硅酸盐纳米复合阻燃材料等方面，阐述了硅系阻燃剂近几年的发展情况；介绍了有机硅系阻燃剂、无机硅系阻燃剂；评述了硅系阻燃剂具有高效、低毒、抑烟和促进成炭等优点；综述了含硅基团共聚物、含硅接枝共聚物及聚合物／层状硅酸盐纳米复合材料的结构和阻燃性能。     

阻燃聚苯乙烯/层状无机纳米复合材料的研究进展

综述了阻燃聚苯乙烯(PS)/蒙脱土(MMT)纳米复合材料、阻燃PS/双氢氧化物(LDH)纳米复合材料、阻燃PS/石墨烯(GO)纳米复合材料的阻燃性能和热稳定性能,利用添加型或反应型阻燃剂制备的上述3种复合材料的阻燃性能和热性能都有大幅度的提高。最后展望了阻燃PS/层状无机纳米复合材料的研究和应用前景。     

聚合物/层状硅酸盐纳米复合材料阻燃性能的全面评价

从热释放速率、质量损失速率、引燃时间、火灾性能指数、氧指数和UL94阻燃级别等方面,对聚合物/层状硅酸盐纳米复合材料(PLN)的阻燃性能进行了全面评价,探讨了PLN的阻燃机理,指出了未来PLN的研究方向。     

聚乳酸/层状硅酸盐纳米复合材料研究进展

介绍了聚乳酸/层状硅酸盐纳米复合材料研究进展,阐述了其制备方法如原位聚合插层法、溶液插层法、熔融插层法等,详述了聚乳酸添加纳米层状硅酸盐后结构与性能的变化,包括复合材料的微观结构、结晶性能、热性能、力学性能、流变性能、加工性能、阻隔性能、阻燃性能的变化。研究表明,采用不同的制备方法如原位聚合插层法、溶液插层法、熔融插层法等能制得插层型、剥离型以及插层与剥离混合型聚乳酸/层状硅酸盐纳米复合材料;添加纳米层状硅酸盐后,得到的聚乳酸/层状硅酸盐纳米复合材料结晶速率提高,结晶度增加,说明层状硅酸盐起到了成核剂的作用;热稳定性、拉伸模量和冲击强度、阻透性能和阻燃性能都有不同程度提高;流变性能也得到改善。     

可降解热塑性淀粉/层状硅酸盐纳米复合材料的研究进展

热塑性淀粉/层状硅酸盐纳米复合材料具有常规热塑性淀粉材料所没有的结构、形态以及较常规热塑性淀粉材料具有更优异的机械性能、耐热性能和气体、液体阻隔性能等而显示出重要的科学意义和应用前景.本文综述了目前国内外热塑性淀粉/层状硅酸盐纳米复合材料的发展现状,并对其应用前景进行了展望.     

热塑性聚合物/木纤维复合材料的阻燃研究进展

综述了近年来国内外热塑性聚合物/木纤维复合材料的阻燃性能的研究成果,分析了热塑性聚合物/木纤维复合材料的阻燃机理,介绍了无机阻燃体系、膨胀型阻燃体系、纳米粒子阻燃体系和复合阻燃体系等无卤阻燃剂对热塑性聚合物/木纤维复合材料的阻燃性能和力学性能的影响。最后,展望了热塑性聚合物/木纤维复合材料阻燃的发展方向。     

纳米层状石墨/六方氮化硼协效膨胀阻燃EP复合材料的制备与阻燃特性研究

首先将环氧树脂与少量膨胀阻燃剂进行复配出环氧树脂/膨胀阻燃复合材料,再将石墨、氮化硼两种材料同时进行微波剥离,制备出纳米层状石墨/纳米氮化硼,将其与环氧树脂/膨胀阻燃复合材料进行协效阻燃,制备出阻燃型环氧树脂复合材料。分别研究了微波剥离出的纳米层状石墨/氮化硼作为协效阻燃剂对复合材料的热稳定性能、燃烧性能、固化行为的影响。使用扫描电子显微镜观察石墨、氮化硼剥离前后的差异,发现经合适的微波剥离工艺可有效制备纳米层状石墨/纳米氮化硼;使用热重分析仪对比纳米层状石墨/纳米氮化硼环氧树脂复合材料与环氧树脂/膨胀阻燃复合材料的热稳定性,结果表明残炭率提高了30%;使用锥形量热仪对比纳米层状石墨/纳米氮化硼环氧树脂复合材料与环氧树脂/膨胀阻燃复合材料的燃烧性能,结果表明燃烧时间延长了51 s,平均热释放速率降低了29%。     

Nanocomposites: a new class of flame retardants for polymers

Nanocomposites are a new class of polymer systems. Modified layered silicates as fillers are dispersed at a nanometre-level within a polymer matrix and new extraordinary properties are observed. Through nanocomposite formation the thermal stability and flame retardancy of polymers are also improved. The flame retardancy of layered silicate nanocomposites is based on char formation and its structure. Dr. Günter Beyer of Kabelwerk Eupen AG in Belgium reviews the current state of development of nanocomposites as a new class of flame retardants for polymers.     

辐照法制备无卤阻燃HDPE/EPDM/硅橡胶共混物

以氢氧化镁和红磷为阻燃剂,硅橡胶、三元乙丙橡胶(EPDM)为共混材料,高密度聚乙烯(HDPE)为基体制备了阻燃共混物,并对其进行电子束辐照,考察了阻燃共混物的力学性能、阻燃性能和微观形貌。结果表明:EPDM的加入明显改善了阻燃共混物的力学性能;硅橡胶的加入使得无机阻燃剂粒子在聚合物基体中的分散性提高,阻燃共混物的氧指(数OI)提高;辐照交联后,阻燃共混物的拉伸强度增强,OI明显提高,燃烧后的炭层更加致密。     

Magnesium hydroxide nanoparticles grafted by DOPO and its flame retardancy in ethylene-vinyl acetate copolymers

Magnesium hydroxide (MH) nanoparticles have been considered as an excellent nonhalogen flame-retardant. However, the drawbacks of easy aggregation and relatively low flame retardancy limit their applications in polymer materials. In this research, MH nanoparticles were successfully grafted by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) through the bridge of vinyl silane coupling agents (WD70). The grafted MH nanoparticles (MH-WD70-DOPO) were characterized by Fourier transform infrared spectra, ³¹P nuclear magnetic resonance spectra, thermogravimetric analysis, transmission electron microscopy, and X-ray photoelectron spectroscopy spectra. MH-WD70-DOPO nanoparticles were incorporated into ethylene-vinyl acetate copolymer (EVA) matrix by melt blending method. The results indicated that MH-WD70-DOPO nanoparticles were much homogenously dispersed in EVA matrix than unmodified MH particles. EVA/MH-WD70-DOPO nanocomposites with 51.32 wt% loading showed higher flame retardancy, better mechanical and processing properties compared with EVA/MH-WD70 sample. These findings could provide a novel method to enhance the flame-retardant efficiency of inorganic hydroxide flame retardants, while keeping good mechanical and processing properties of polymer materials.     

Thermal Properties and Flammability of Ethylene-Vinyl Acetate Copolymer/Montmorillonite/Polyethylene Nanocomposites with Flame Retardants

Ethylene-vinyl acetate copolymer (EVA)/montmorillonite (MMT) composite was blended with a linear low density polyethylene (LLDPE). X-ray diffraction and transmission electron microscopy (TEM) image of the EVA/MMT composite are in support of an intercalated with partially delaminated nanocomposite. The tensile strength of the nanocomposite is about 20% higher than that without layered silicates, MMT. Furthermore, the incorporation of MMT into polymer blend delays the main thermo-oxidative degradation. Cone calorimeter test points out that the addition of layered silicates into the pristine EVA/LLDPE blend or the blend with a low smoke non-halogen (LSNH) fire retardants, aluminum trihydroxide, and antimony trioxide, can reduce the maximum heat release rate by 30–40%. The smoke suppressing effect of layered silicates is only observed in the nanocomposite containing flame retardants. According to the limiting oxygen index (LOI) data and cone calorimeter test, the addition of the nanodispersed layered silicate and LSNH flame retardants to the EVA/LLDPE exhibits a synergistic effect on the flame retardancy and smoke suppression.     

Molecular design and properties of intrinsic flame-retardant P-N synergistic epoxy resin

In recent years, the poor weather resistance and aging resistance of additive flame retardants have caused researchers to pay attention to reactive flame retardants. A novel P-N coacting epoxy curing agent with intrinsic flame retardancy was designed and synthesized. The mechanical properties, crosslinking curing properties and flame-retardant properties of intrinsic flame-retardant epoxy resin were characterized. The results show that the cross-linking curing performance of hexa (3,5-diamino-1,2,4 triazolyl)-cyclotriphosphonitrile) (VCP) is lower than that of DDM. This is due to the decrease in cross-linking density caused by the VCP ring molecular structure. Therefore, the mechanical properties of the epoxy resin cured with VCP decreased, but the flame-retardant properties of the material significantly improved. The limiting oxygen index of the VCP/EP flame retardant epoxy thermosets was 27.3%, reaching the UL 94 V-1 level. The peak heat release rate and total heat release rate of the VCP/EP flame retardant epoxy thermosets were significantly reduced. The flame retardancy mechanism was studied by Fourier transform infrared spectroscopy, scanning electron microscopy, energy dispersive spectroscopy, and x-ray photoelectron spectroscopy. The results show that the intrinsic flame-retardant P-N coacting epoxy resin has excellent curing and flame-retardant properties.     

阻燃型木塑复合材料研究进展

综述了近年来阻燃型木塑复合材料的研究成果.分析了木塑复合材料的燃烧特性,并总结了铝-镁系阻燃剂、膨胀型阻燃剂、磷系阻燃剂及纳米粒子阻燃剂等无卤阻燃剂对木塑复合材料的阻燃性能和力学性能的影响;结合木塑复合材料阻燃过程中存在的问题对其研究的趋势进行了展望.     

不同膨胀型阻燃剂改性聚丙烯/聚乳酸复合材料

用两种不同的膨胀型氮磷阻燃剂(IFR1和IFR2)阻燃改性聚丙烯(PP)/聚乳酸(PLA)复合材料。结果表明:两种阻燃剂在PP/PLA基体中都具有良好的分散性和界面粘合性。阻燃剂的加入降低了材料的力学性能,而含有25%阻燃剂的PP/PLA复合材料就能到达垂直燃烧试验(UL-94)的V0等级。燃烧过程中阻燃剂通过在材料表面形成致密的炭层来提高材料的阻燃性,其中IFR1对PP/PLA体系的阻燃改性效果更好。从力学性能和阻燃效果的双重考虑,质量含量25%的阻燃剂适合于PP/PLA材料的阻燃改性。     

阻燃聚氨酯的研究及应用进展

聚氨酯材料具有良好的物理力学性能、优异的耐候性和保温性能,应用广泛。但聚氨酯极易燃烧,极大地限制它的使用范围,所以急需提高聚氨酯的阻燃性能。本文介绍了聚氨酯的阻燃必要性,从聚氨酯结构自阻燃和引入阻燃剂等方面综述了聚氨酯阻燃方法的最新研究进展,重点介绍添加型阻燃剂复配使用、反应型阻燃剂协同阻燃以及纳米材料复合阻燃聚氨酯,同时阐述了不同类型阻燃剂的作用机理,并展望了聚氨酯阻燃的发展趋势,加强对聚氨酯结构自阻燃深入研究,阻燃剂复配技术的完善。     

高分子材料阻燃与抑烟的分立设计思想

随着高分子材料在人类生产生活中的广泛应用,其防火安全性问题日益凸显,高效环保阻燃抑烟剂的开发成为当前材料领域亟待解决的问题之一。然而,与发展较为成熟的阻燃剂研究领域相比,世界各国在抑烟剂方面的研究普遍处于起步和初期发展阶段。同时,多数抑烟剂的研究处于阻燃剂的从属地位,即在阻燃剂的基础上附加抑烟的性能,对单功能抑烟剂的开发重视度不够,限制了其进一步的发展。高分子材料中结构和官能团的多样性使其燃烧和发烟机理有显著不同,因此针对不同种类的高分子材料的燃烧和发烟过程,其阻燃和抑烟剂在组成和结构上的设计亦应有明显区别。以同一种材料实现阻燃和抑烟的兼顾,往往顾此失彼,导致两者性能均无法得到最大的发挥。因此,本文提出将阻燃剂和抑烟剂的功能分离开来的设计思想,加强单功能抑烟剂的研究投入,对阻燃/抑烟材料的化学组成和结构分别进行有针对性的设计,再进行功能优化复配,将是实现高分子材料高效阻燃抑烟的有效途径之一。     

Flammability of polystyrene layered silicate (clay) nanocomposites: Carbonaceous char formation

Polymer layered‐silicate (clay) nanocomposites have not only the unique advantage of reduced flammability, but also improved mechanical properties. This is a key advantage over many flame retardants, which reduce flammability but also reduce the mechanical properties of the polymer. In our efforts to further understand the mechanism of flame retardancy with polymer‐clay nanocomposites, we investigated the effect of the clay, the loading level and polymer melt viscosity on the flammability of polystyrene‐clay nanocomposites. The nanoscale dispersion of the clay in the polymer was analysed by wide‐angle X‐ray diffraction (XRD) and transmission electron microscopy (TEM). Cone calorimetry and gasification studies were used to evaluate the flammability of these nanocomposites. There were major reductions in peak heat release rates (HRRs), and increased carbonaceous char formation, for these nanocomposites. It was determined that while the viscosity of the PS nanocomposite played a role in lowering the peak HRR, the clay loading level had the largest effect on peak HRR. Finally, it was found that clay catalysed carbonaceous char formation, and the reinforcement of the char by the clay was responsible for the lowered flammability of these nanocomposites. Published in 2002 by John Wiley & Sons, Ltd.