Red phosphorus–controlled decomposition for fire retardant PA 66

The thermal degradation and the combustion behavior of glass fiber–reinforced PA 66 materials containing red phosphorus were investigated. Thermogravimetry (TG), TG coupled with FTIR, and TG coupled with mass spectroscopy were used to investigate the thermal decomposition. The flame retardant red phosphorus was investigated with respect to the decomposition kinetics and the release of volatile products. The combustion behavior was characterized using a cone calorimeter. Fire risks and fire hazards were monitored versus external heat fluxes between 30 and 75 kW/m². Red phosphorus acts in the solid phase and its efficiency depends on the external heat flux. The use of red phosphorus results in an increased amount of residue and in a corresponding decrease in total heat release. The decrease of the mass loss rate peak results in a corresponding decrease of the peak heat release. With increasing external heat flux applied the first effect on the total heat release decreases linearly, whereas the second effect on the peak heat release expands linearly. The investigation provides insight into the mechanisms of how the fire retardant PA 66 is achieved by red phosphorus controlling the degradation kinetics. Taking into account that a decrease of the volatile products also leads to a decrease of heat production in the flame zone and that the char acts as heat transfer barrier, a reduced pyrolysis temperature is suggested as a further feedback effect. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 83: 2060–2071, 2002     

软质PVC阻燃抑烟的研究

介绍了各类阻燃剂(如氢氧化铝、氢氧化镁、锑系、磷系、硼系、钼系)的性能及阻燃机理,并对软质PVC材料的阻燃抑烟性能进行了实验。结果表明：经偶联剂处理过的阻燃剂,由于增强了其与基体的界面结合力。从而使其力学性能得到提高;三氧化钼的用量对聚合物的阻燃效果影响不明显,而随着硼酸锌和三氧化二锑用量的增加,其阻燃效果越来越好。     

Influence of fire retardants on the reaction‐to‐fire properties of coextruded wood–polypropylene composites

The reaction‐to‐fire properties of coextruded wood–plastic composites containing different fire retardants (melamine, zinc borate, ammonium polyphosphate, aluminium trihydroxide, natural flake graphite and expandable graphite) in the shell layer have been studied with the cone calorimetry technique. The effect of ammonium polyphosphate in combination with graphite has also been studied with a cone calorimeter test. A coextruded composite manufactured without any fire retardant addition has been used as a reference. The fire properties measured in the cone calorimeter are discussed, including the heat release rate, total heat release, smoke production, specific extinction area, CO yield and mass loss rate. The results show that the introduction of fire retardants in the shell layer of coextruded wood–polypropylene composites has a favourable effect on the fire resistance properties of the composite materials. The reaction‐to‐fire properties have been improved according to the fire classification of construction products based on the Euroclass system. Copyright © 2015 John Wiley & Sons, Ltd.     

新型无卤阻燃填料在PVC中的应用

研究了新型无卤阻燃填料有其在PVC中的应用，为含氯高分子材料的阻燃研究提供了新方法、新途径。     

Evaluation of the effectiveness of the fire retardant mixture containing potassium carbonate using a cone calorimeter

This article presents the results of investigations obtained for a wood fire retardant agent which is currently under production. Experiments were conducted using a mixture of potassium carbonate and urea in accordance with the PN‐C‐04914 standard (the Polish equivalent of ISO 5660‐1). Wood samples of Scots pine (Pinus sylvestris L.) were treated with the above mixture as well as with its individual components. It was observed that impregnation of samples with potassium carbonate and a mixture of potassium carbonate and urea has an advantageous influence on the reduction of the heat release and the heat of combustion, and also prolongs the time to ignition. Urea alone failed to exert a fire‐retardant effect on wood samples. Copyright © 2011 John Wiley & Sons, Ltd.     

无机复合阻燃消烟剂在PVC材料中的应用

分析了高分子材料阻燃消烟的必要性，报道了研制的SY928系列无机复合阻燃消烟剂在PVC电工套管和电缆料中的应用效果。     

The effect of fibre content on the thermal and fire performance of polypropylene–glass composites

Thermoplastic composites demand constant improvements in fire retardant and mechanical properties to fulfil their full market potential, especially in demanding sectors such as rail, aerospace and infrastructure, where fire performance is critical. The aim of this work is to understand the effect of reinforcing fibres on the flammability of polypropylene–glass (P‐G) composites and the means of improving their fire performance in a cost‐effective manner. A number of P‐G composites with 0%, 10% and 20% (w/w) glass fibres were prepared using short length glass fibres. The effect of fibre content on the thermal stability, flammability and mechanical performance of the P‐G composites without and in the presence of conventional fire retardants was studied. It was observed that while the presence of glass fibre lowered down the limiting oxygen index value of the composite, the rate of flame spread in a UL‐94 equivalent test was also lowered. The reduction in limiting oxygen index is due to the fact that glass fibre reduces the melt dripping behaviour of polypropylene and does not let the polymer (polypropylene) move away from flame, which then burns. Cone calorimetric study indicated that the presence of glass fibre reduces the overall flammability of the composite laminate. Copyright © 2011 John Wiley & Sons, Ltd.     

Influence of mineral fillers on the fire retardant properties of wood‐polypropylene composites

The effects of mineral fillers on the fire retardancy of wood‐polypropylene composites have been studied. Wood‐polypropylene composites containing mineral fillers have been compounded in a conical twin‐screw extruder. A composite manufactured without any mineral filler addition has been used as a reference. The flame resistance properties of the composite materials have been studied using the cone calorimeter. The results show that the introduction of mineral fillers into the wood‐polypropylene composites has a favourable effect on the fire resistance properties of the composite materials. The reaction‐to‐fire properties have been improved according to the fire classification of construction products based on the Euroclass system. Copyright © 2012 John Wiley & Sons, Ltd.     

沸石对PVC阻燃抑烟作用的研究

沸石多孔具有吸附功能,通过TG、SEM等研究了沸石对PVC的阻燃抑烟作用。研究表明:沸石能吸收HCl,减少PVC燃烧过程中HCl的表观释放量,沸石对PVC具有一定的阻燃作用,在PVC/沸石的炭层表面有沸石覆盖层,起到较好的绝热屏蔽作用。在PVC/沸石燃烧残余物的炭层内部有沸石填充,基材、碳和沸石形成复合材料提高阻燃作用。     

Modification of rubber wood with styrene in combination with diethyl allyl phosphate as the flame‐retardant agent

Rubber wood (Hevea brasiliensis) polymer composite was prepared using styrene as the monomer in combination with diethyl allyl phosphate (DEAP) to improve flame‐retardant property. DEAP was synthesized, characterized and incorporated into wood with styrene. The polymerization was accomplished by catalyst heat treatment using AIBN as the catalyst. The properties of wood–polymer composites (WPC) like water absorption, swelling in water, hardness, modulus of elasticity (MOE), modulus of rupture (MOR) etc. were improved on treatment. The thermal degradation behavior of WPC was evaluated using thermogravimetric analysis (TGA) and the flammability of the WPC was evaluated using the limiting oxygen index (LOI) test. It was observed that fire retardancy of WPC improved on incorporation of DEAP. FTIR spectroscopy and SEM study showed the interaction between wood and the polymers. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2007     

The rapid mass calorimeter: A route to high throughput fire testing

The rapid mass calorimeter based on reduced‐size specimens is proposed for accelerated fire testing and put up for discussion, particularly for flame retarded polymeric materials. A mass loss calorimeter is combined with a semiautomatic sample changer. Experiments on specimens of reduced size were conducted on poly(methyl methacrylate), poly(propylene), polyamide 66, poly(ether ether ketone), and pine sapwood square samples with edge lengths of 100, 75, 50, 25, 20, and 10 mm. Specimens of 20 × 20 mm² were selected to achieve a crucial reduction in specimen size and a measuring protocol developed. A total of 71 different polymeric materials were investigated in the rapid mass calorimeter and cone calorimeter for comparison and several materials with different heat release rate characteristics in the pyrolysis combustion flow calorimeter to test this additional screening method as well. The important fire properties obtained in the rapid mass calorimeter show reasonable correlation with the cone calorimeter results but also with the oxygen index. All in all, the rapid mass calorimeter produces reliable and meaningful results and, despite acceleration and size reduction, still allows for a certain degree of burning behavior interpretation. Material savings of 96% and time savings of around 60%‐70% are achieved compared to measure cone calorimeter.     

聚氯乙烯项目消防审核分析

介绍了聚氯乙烯生产过程中存在的消防安全隐患并提出了相应的解决措施。     

用锥形量热仪研究聚氨酯泡沫的阻燃性能

在50 kW/m2辐射功率下,利用锥形量热仪研究了氢氧化铝、卤系阻燃剂、氮系阻燃剂和磷系阻燃剂阻燃聚氨酯泡沫(PUF)的阻燃特性,获得了点燃时间、最大热释放速率、总热释放、比消光面积及质量损失速度等参数。结果表明,将热释放速率、燃烧总释放热和烟气释放量作为材料阻燃性能好坏的评价指标,阻燃剂聚磷酸铵（APP）和三聚氰胺磷酸盐（MP）是PUF的理想阻燃剂。     

聚氯乙烯阻燃抑烟研究进展

综述了近年来PVC的发烟机理,无机和有机阻燃抑烟剂改性PVC的研究进展。     

Thermal properties of polyethylene flame retarded with expandable graphite and intumescent fire retardant additives

Low‐density polyethylene was flame retarded by combinations of expandable graphite with either ethylenediamine phosphate or 3,5‐diaminobenzoic acid phosphate. Cone calorimeter, laser pyrolysis, and open flame exposure tests (supported by video and infrared camera data capture and analysis) were conducted to assess ignition and burn behavior. Cone calorimeter results indicated substantial reductions in the peak heat release rates for all flame‐retarded samples but with reduced ignition times and increased flame out times. Smoke generation was suppressed in the presence of expandable graphite. Infrared and video data from open flame fire tests indicated cohesive bonding of expanded strings and thermal shielding properties in all binary systems. All binary systems delivered fire retardation exceeding any of the single fire retardant compounds. They were also able to withstand higher temperatures before ignition, burn through, or sag occurred. All ethylenediamine phosphate‐containing binary systems prevented sample burn through, maintaining structural integrity of samples until eventual melting of the polymer media occurred. Thermogravimetric analysis laser pyrolysis results confirmed the good thermal shielding imparted by the intumescent additives. Copyright © 2016 John Wiley & Sons, Ltd.     

Expandable graphite: A fire retardant additive for polyurethane coatings

The study investigates the mechanism of fire retardancy induced by expandable graphite in a polyurethane coating. A complementary investigation to the spectroscopic study performed previously confirms that little interaction occurs between the matrix and the additive. X‐ray diffraction study demonstrates that the crystalline structure of the graphite is maintained during the intumescent process. The presence of free radicals in the protective shield is then demonstrated but at low concentration compared with classical intumescent systems, such as for example polyurethane/ammonium polyphosphate. Finally, the physical properties of the char are then investigated. Blowing measurement demonstrates the high degree of expansion of the layer which may partially explain the fire retardant performance of expandable graphite in polyurethane. Surface analyses by optical microscopy and optical profilometry also enable a better understanding of the efficiency of expandable graphite. In the absence of a fire retardant additive the coating displays cracks and holes, providing a pathway for oxygen diffusion as well as heat and mass transfer between the flame and the virgin polymer. Both phenomena are limited when expandable graphite is added to polyurethane. Consequently, fire retardancy of expandable graphite results more from a physical than from a chemical action. Copyright © 2003 John Wiley & Sons, Ltd.     

Investigation of a combustible material in the fire of Hengyang merchant's building

Agaric, a kind of important combustible material in the fire of Hengyang merchant's building, was investigated using different experiment equipments. Its degradation and pyrolysis behavior were studied by means of thermogravimetric and kinetic analysis and pyrolysis gas chromatography–mass spectroscopy analysis. External radiation heat and internal heat were used to ignite the agaric. For external radiation ignition, a series of bench‐scale fire tests were done in cone calorimeter in accordance with ISO 5660. As for the internal heat ignition, a fire test was carried out in a full‐scale room in accordance with ISO 9705. Multi‐parameter measurement, including heat release rate (HRR), mass loss rate (MLR), temperature field and species concentration, has been accomplished. Meanwhile, the process of a full‐scale fire test was numerically simulated. The computational results were consistent with experiment data, which will lay down a good foundation for further study in fire reconstruction of the whole fire. Copyright © 2008 John Wiley & Sons, Ltd.     

The effect of accelerated ageing of building wires

The fire performance of two electric cables (building wires) designed for indoor use has been tested, both as new products and after accelerated thermooxidative ageing. The cables were aged for a maximum time of 16.5 weeks at 80°C. The cables are commercially available, and were constructed using a PVC material in one case and a non‐halogenated polyolefin‐based material, called Casico, in the other. The effects of ageing on the fire performance of the cables, and the chemical changes that have caused the observed fire behaviour, have been investigated and are discussed. Special attention is paid to the behaviour of the plasticizers that are used in the PVC cable, and how the fire behaviour is affected by the loss of plasticizers from the cable and by the migration of plasticizers between the parts of the cable (insulation, bedding and sheathing). Copyright © 2007 John Wiley & Sons, Ltd.     

Effects of natural weathering on the fire properties of intumescent fire‐retardant coatings

Fire‐retardant coatings could be one option for providing enhanced protection to buildings during a wildfire, particularly when applied to combustible siding and in under‐eave areas. Limited studies have been conducted on their effectiveness but maintaining adequate performance after weathering has been questioned. This paper reports on a study evaluating the effect of natural weathering on the performance of intumescent‐type fire‐retardant coatings. The main concerns were (a) the reduction of ignition resistance of the coating after weathering and (b) the coating might contribute as a combustible fuel and assist the fire growth after weathering. This study evaluated the performance of 3 intumescent coatings that were exposed to natural weathering conditions for up to 12 months. A bench‐scale evaluation using a cone calorimeter was used to evaluate the performance of the coatings at 3 heat flux levels (30, 50, and 70 kW/m²). Our results showed that weathering exposure reduced the effectiveness of fire protection of intumescent coatings, but the weathered coatings did not act as additional fuels. Weathering orientation showed much less effect on the performance of intumescent coatings in comparison to other parameters. There was statistical evidence that weathering duration, heat flux level, and coating type affected the combustion properties.     

Cone calorimeter evaluation of two flame retardant cotton fabrics

Unbleached (gray) cotton needle‐punched nonwoven (NW) fabrics with 12.5% polypropylene scrim were treated with two phosphate–nitrogen‐based flame retardant (FR) formulations, Southern Regional Research Center (SRRC)‐1 and SRRC‐2. The SRRC‐1 formulation contains diammonium phosphate as the FR chemical along with urea and dimethyloldihydroxyethyleneurea. Because a trace amount of formaldehyde was still expected to be released from SRRC‐1‐treated FR cotton under high heat, it was preferable to eliminate the dimethyloldihydroxyethyleneurea, leading to the revised formulation SRRC‐2. It has a higher content of diammonium phosphate and did not use the polyethylene emulsion that was in SRRC‐1. Both formulations were of low cost as they were developed at SRRC using industrial grade chemicals. The fabrics were evaluated with a cone calorimeter using three heat flux levels, 20, 30, and 50 kW/m². On the basis of the overall cone calorimeter results for heat released and ignition times, FR NW fabrics that were treated with SRRC‐2 were found to be slightly superior in flammability properties to those treated with the earlier SRRC‐1 formulation, but the differences were statistically insignificant. Both preparations were much less flammable than the untreated control cotton NW fabrics. Compared with the untreated NW fabrics, the FR fabrics had higher visible smoke production. Copyright © 2012 John Wiley & Sons, Ltd.