Fire and flame retardants for PVC

The flammability performance of PVC plays a significant role in its selection for many applications. Its relatively high chlorine content (56.8%) makes it more resistant to ignition and burning than most organic polymers. In the case of flexible PVC, the plasticizers that contribute flexibility in most instances detract from its resistance to fire. To meet specifications such as oxygen index, heat release, smoke evolution, or extent of burning in cable tests, flame‐retardant (FR) and smoke‐suppressant (SS) additives are often incorporated. Synergistic combinations of FR and SS additives help PVC formulations meet many stringent FR specifications cost effectively.     

纳米阻燃抑烟PVC的研究进展

PVC是一种应用广泛的高分子材料,但因其具有热稳定性差、易燃烧、发烟量大的缺点而限制了发展,因此PVC的阻燃与抑烟成为阻燃科学研究领域的关键问题之一。纳米型阻燃抑烟剂克服了传统型阻燃抑烟剂添加量大、阻燃抑烟效果不明显的缺点,为研究和解决PVC阻燃抑烟提供了一个新途径。本文介绍了PVC纳米阻燃抑烟剂的制备方法、表征手段及其在PVC中的应用以及PVC降解、阻燃与抑烟的表征,最后简要论述PVC阻燃抑烟的发展趋势。     

PVC阻燃材料在建筑中的应用

主要介绍了无机阻燃剂、有机阻燃剂和复合型阻燃剂改性的聚氯乙烯(PVC),以及这些阻燃剂对PVC阻燃性能的影响。其中无机阻燃剂的阻燃效果最为明显,不过消烟效果较差;有机阻燃剂消烟效果较为明显,但阻燃能力不如无机阻燃剂;复合型阻燃剂兼具有机/无机阻燃剂的优点,或具有多种无机阻燃剂的优点,一般既具有较强的阻燃能力,又具有较为显著的消烟效果,是未来PVC用阻燃剂的发展方向。     

Recent developments in plasticized flame retardant polyvinyl chloride (PVC)

Triaryl and alkylaryl phosphates are plasticizers/flame retardants for polyvinyl chloride. The former are more effective flame retardants and the latter are better plasticizers. The latter also gives less smoke. A new phosphate ester blend with good plasticizer properties and low smoke is reported. A brominated triaryl phosphate ester is shown to be a highly effective flame retardant giving plasticized polyvinyl chloride compositions with oxygen index values up to 36. These compositions are suitable for high temperature wire and cable products.     

PVC阻燃抑烟的研究进展

介绍了聚氯乙烯(PVC)的热降解机理及燃烧特性。综述了PVC阻燃抑烟剂(如阻燃增塑剂、金属化合物、含硼阻燃剂、微胶囊红磷和无机填料等)的研究,特别提及了一些过渡金属(如Mo、Cu与Fe的化合物)在PVC抑烟中的明显作用。比较了各种阻燃抑烟方法的优缺点。采用阻燃剂和抑烟剂复合对PVC协同阻燃抑烟是未来的研究方向。     

系列羟基锡酸盐对半硬质PVC的阻燃消烟作用

研究了系列羟基锡酸盐阻燃剂对半硬质PVC的阻燃消烟作用。通过对样品燃烧后剩炭含量及扫描电镜(SEM)分析,探讨了锡酸盐体系阻燃抑烟的机理。结果表明:经阻燃处理的样品具有较高的极限氧指数(LOI)和剩炭率,较低的烟密度等级(SDR)和最大烟密度(MSD),与未处理的样品相比具有较好的阻燃和消烟性能。由于阻燃剂的添加量较少,对材料力学性能影响不大。     

ABS塑料阻燃改性研究

报道了PVC,PVC／Sb2O3,DBDPO/Sb2O3对ABS塑料的燃烧性能、力学性能和加工性能的影响规律。研究表明：DBDPO／Sb2O3复合阻燃剂对ABS阻燃效果最佳,PVC／Sb2O3次数次之,PVC只有在添加量较大时才显示良好的阻燃效果。     

Metal hydroxystannates as flame retardants and smoke suppressants for semirigid poly(vinyl chloride)

Metal hydroxystannates were studied as flame retardants and smoke suppressants for semirigid poly(vinyl chloride) (PVC). The flame‐retardant and smoke‐suppression mechanisms were investigated by using limiting oxygen index (LOI), smoke density rating (SDR), the solid yield test (SY), scanning electron microscopy (SEM), thermogravimetry, differential thermogravimetry, and differential thermal analysis. Results showed that semirigid PVC treated with the flame retardants had a higher LOI, and solid yield, but a lower SDR and maximum smoke density, thereby indicating that the flame‐retardance and smoke‐suppression properties of the treated PVC were improved and that the hydroxystannate compounds could be used as highly effective flame retardants. The tin compounds may exert their action in both the condensed and vapor phases, but mainly in the condensed phase as Lewis acids. J. VINYL ADDIT. TECHNOL., 2008. © 2008 Society of Plastics Engineers.     

PVC软制品阻燃体系的设计

介绍了进行PVC软制品阻燃体系设计必须了解的基础知识和基本思路。根据不同制品不同的阻燃要求,如何科学合理的设计阻燃体系,使阻燃和抑烟都有良好的表现,同时兼顾生产成本和环境友好性,是PVC软制品生产者必须面对的重要技术课题,也是企业能否取得竞争优势的重要因素之一。     

阻燃抑烟剂对软聚氯乙烯材料燃烧性能的影响

针对氢氧化镁、硼酸锌、三氧化二锑等常用的阻燃抑烟剂对在软聚氯乙烯燃烧时的热释放速率和一氧化碳释放量进行了研究 ,发现氢氧化镁和硼酸锌虽然可以降低材料的热释放性能和发烟量 ,但是会大大增加烟气中一氧化碳的释放量 ;而三氧化二锑会增加材料的发烟量 ,但却能大大降低烟气中的一氧化碳的释放量     

PVC阻燃抑烟研究进展

综述了近几十年来PVC阻燃抑烟方面的研究成果,对PVC阻燃抑烟体系的各类及特点、阻燃抑烟机理、评定指标、分析测试方法进行了总结和评述,同时对PVC阻燃抑烟体系今后的研究方向做了展望。     

金属配合物对软聚氯乙烯的阻燃消烟作用

利用热分析的方法研究了以Al(OH)3和Mg(OH)2为基础，含有Fe、Co、Ni或Cu的金属配合物的复合阻燃剂对软聚氯乙烯(PVC)的阻燃消烟作用。研究了软PVC从室温到1073K的热降解过程。利用Kissinger方程给出了其动力学参数。结果表明：阻燃处理过的软PVC具有较好的阻燃消烟性能，如较高的氧指数和剩炭率，较低的烟密度等级和最大烟密度，力学性能有所降低。     

High‐molecular‐weight flexibilizers in low‐smoke flame‐retardant PVC compounds

Ethylene copolymer resin (ECR) modifiers play an important role in low‐smoke PVC. As high‐molecular‐weight flexibilizers, these resins reduce smoke and add strength and low temperature flexibility. This combination allows compounders to increase the amounts of flame‐retardant additives without compromising strength or flexibility or by adding liquids which increase smoke. This paper demonstrates these attributes versus liquid plasticizers used in PVC compounds.     

Evaluation of the smoke and flammability characteristics of polymer systems

Using Oxygen Index and the XP-2 test to measure flammability and smoke characteristics, a broad spectrum of thermoplastic and thermoset polymers, both commercial and experimental, were investigated to elucidate the effect of structure on fire properties. In general, polymers with aliphatic backbones are very flammable, but their tendency to generate smoke is minimal. The addition of flame retardants, especially halogen compounds, while reducing their tendency to burn, increases the evolution of smoke. Halogen-containing polymers are usually non-flammable, with high Oxygen Indices, but display high smoke generation. Polymers containing an aromatic group in the side chain, such as polystyrene, are both highly flammable and high smoke producing. However, polymers with the aromatic group in the main chain, such as polysulfone, polycarbonate and polyphenylene oxide, are intermediate in both Oxygen Index and smoke generation. After investigation of the various test methods available, it is concluded that no one test will be satisfactory to measure the flammability characteristics of polymers and that a combination of methods must be used.     

Effect of phosphate esters on PVC flammability from a multi-test viewpoint

Many tests have been developed to provide relative flame/smoke data. In spite of the proliferation of such tests and test equipment, many chemical and polymer producers, as well as fabricators, use only one technique to evaluate the flame/smoke properties of a polymer system. This paper demonstrates the importance of multi-method testing to rate the efect of phosphate esters and various fillers on PVC flammability and smoke generation.     

Aryl phosphate ester fire‐retardant additive for low‐smoke vinyl applications

Additives that act as flame retardants can contribute significantly to smoke generation because they decrease the efficiency of the fuel source and, as a result, create a sooty combustion. Work on a new phosphate ester material has shown interesting results and synergies that complement both flame retardancy and low smoke generation in flexible vinyl compositions. This new proprietary aryl phosphate was examined in both neat and blended systems and compared to other typical phosphate ester fire‐retardant (FR) compounds for vinyl. Additionally, the flammability and smoke effects were measured with and without other common vinyl FR additives (zinc borate and ammonium octamolybdate). J. Vinyl Addit. Technol. 10:187–192, 2004. © 2004 Society of Plastics Engineers.     

粉煤灰/三氧化二锑对软质聚氯乙烯阻燃消烟作用研究

将粉煤灰(Flyash)、三氧化二锑(Sb₂O₃)复合阻燃剂加入软质聚氯乙烯(PVC),制备PVC/Sb₂O₃/Flyash复合材料。通过氧指数(LOI)、TG、锥形量热、SEM等测试,探究Flyash和Sb₂O₃的协同效应,对PVC阻燃抑烟性能的影响。结果表明:当m(PVC)∶m(Sb₂O₃)∶m(Flyash)=100∶4∶3,PVC/Sb₂O₃/Flyash具有较好的阻燃抑烟性能,其LOI可达到33.9%。PVC/Sb₂O₃/Flyash的阻燃抑烟性比PVC/Sb₂O₃和PVC好。PVC/Sb₂O₃/Flyash的热释放速率降低、热稳定性增强,成炭率更高。PVC/Sb₂O₃/Flyash难点燃,火灾性能指数(FPI)大,火灾蔓延指数(FGI)小,降低火灾危险性,阻燃性能优异。     

Thermal behavior and flame retardancy of flexible poly(vinyl chloride) treated with zinc hydroxystannate and zinc stannate

The flame‐retardant and smoke‐suppressant properties of inorganic tin compounds such as zinc hydroxystannate (ZHS) and zinc stannate (ZS) were studied in comparison with those of alumina trihydrate and magnesium hydroxide through the limiting oxygen index test and a smoke density test. The thermal degradation in air of flexible poly(vinyl chloride) (PVC) treated with the above compounds was studied by thermal analysis from ambient temperature to 800°C. The activation energy was calculated by using the Vyazovkin model‐free kinetic method and the Kissinger method. The results showed that tin compounds such as ZHS and ZS could be used as highly effective flame retardants for flexible PVC; these flame retardants enhanced the stability and the activation energy of the oxidation of the char. J. VINYL ADDIT. TECHNOL, 2008. © 2008 Society of Plastics Engineers     

聚氨酯硬质泡沫塑料/可膨胀石墨复合材料的阻燃研究进展

综述了近年来聚氨酯硬质泡沫塑料/可膨胀石墨复合材料的阻燃研究进展,详细介绍了该泡沫复合材料的制备方法、热解性能以及燃烧性能(包括极限氧指数、水平/垂直燃烧速率、热释放速率、CO/CO2生成量比值、成炭性)。分析了泡沫密度、可膨胀石墨含量及粒径、微囊包覆处理以及与其他阻燃剂复配使用对相应泡沫复合材料热稳定性及阻燃性能的影响,并对相关机理进行了深入的探讨。     

Recent Research Progress on the Flame-Retardant Mechanism of Halogen-Free Flame Retardant Polypropylene

Polypropylene (PP) is one of the five kinds of universal polymers that have greatly improved our life qualities. While a pestilent limitation of PP is its flammability. Usually, halogen-containing flame retardants (FRs) are used to improve its flame retard ability. However, the halogen-containing FRs are limited more and more strictly because they would produce environment problems, such as the release of corrosiveness smoke and toxicity combustion products. Hence, the researches of halogen-free FRs to replace the halogen-containing FRs become hot topics. In this article, the recent research progress of halogen-free FRs as additives for polypropylene and the flame retardant mechanism of halogen-free FRs are reviewed.