干旱区生态环境知识资源中心(Arid): Intumescent Coatings as Fire Retardants

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来源ID	NTRS_Document_ID: 20160001017
	Intumescent Coatings as Fire Retardants
	Parker, J. A.; Fohlen, G. M.; Sawko, P. M.; Fish, R. H.
英文摘要	The development of fire-retardant coatings to protect surfaces which may be exposed to fire or extreme heat is a subject of intense interest to many industries. A fire-retardant paint has been developed which represents a new chemical approach for preparing intumescent coatings, and potentially, is very important to fire-prevention authorities. The requirements for a superior coating include ease of application, suitability to a wide variety of surfaces and finishes, and stability over an extended period of time within a broad range of ambient temperature and humidity conditions. These innovative coatings, when activated by the heat of a fire, react to form a thick, low-density, polymeric coating or char layer. Water vapor and sulphur dioxide are released during the intumescent reaction. Two fire-protection mechanisms thus become available: (1) the char layer retards the flow of heat, due to the extremely low thermal conductivity; and (2) water vapor and sulfur dioxide are released, providing fire quenching properties. Still another mechanism functions in cases where the char, by virtue of its high oxidation resistance and low thermal conductivity, reaches a sufficiently high temperature to re-radiate much of the incident heat load. The coatings consist of dispersions of selective salts of a nitro-amino-arornatic compound. Specifically, para-nitroaniline bisulfate and the ammonium salt of para-nitroaniline-ortho sulphuric acid (2-amino-5-nitrobenzenesulphuric acid) are used. Suitable vehicles are cellulose nitrate of lacquer grade, a nitrite-phenolic modified rubber, or epoxy-polysulfide copolymer. Three separate formulations have been developed. A solvent is usually employed, such as methylethyl ketone, butyl acetate, or toluene, which renders the coatings suitably thin and which evaporates after the coatings are applied. Generally, the intumescent material is treated as insoluble in the vehicle, and is ground and dispersed in the vehicle and solvent like an ordinary coating pigment. The char found on intumescence is better in terms of yield and physical properties than chars obtained from many previously known intumescent materials. Prior to intumescence, the coating has a density of 85 pounds per cubic foot. After intumescence, the density is approximately 0.3 pounds per cubic loot. The linear expansion of the coatings ranges from 70 to 200 times the applied coating thickness.
英文关键词	THERMAL CONTROL COATINGS THERMAL PROTECTION FLAME RETARDANTS FIRE PREVENTION TEMPERATURE CHARRING HUMIDITY THICKNESS SPECIFICATIONS ACETATES AMMONIUM COMPOUNDS CELLULOSE NITRATE EPOXY RESINS KETONES NITRO COMPOUNDS SULFUR COMPOUNDS RUBBER ABRASION RESISTANCE POLYMERIC FILMS TOLUENE
出版年	1970
报告类型	Technical Report
语种	英语
国家	美国
URL	http://hdl.handle.net/2060/20160001017
资源类型	科技报告
条目标识符	http://119.78.100.177/qdio/handle/2XILL650/258477
推荐引用方式 GB/T 7714	Parker, J. A.,Fohlen, G. M.,Sawko, P. M.,et al. Intumescent Coatings as Fire Retardants,1970.