Flammable properties, chemical

Because of their toxic, explosive, and flammable properties, chemicals continue to be the weapons of choice for terrorist attacks. As potential weapons of mass destruc-... 

An elementary introduction to chemistry is given in Chapter 3 this serves only to provide background and for more advanced consideration reference will be necessary to specific text books, e.g. as listed in the Bibliography. A brief discussion of the relevance of physicochemical principles to hazard identification is given in Chapter 4. Relevant toxic and flammable properties, and summaries of appropriate precautions to cater for them during handling, use and disposal, are provided in Chapters 5 and 6, respectively. Reactive hazards are discussed in Chapter 7. The special problems with cryogenic materials and chemicals under pressure, typified by compressed... 

The catalyst is formed by reaction of HF on SbClj. The Freons have a unique combination of properties which make them ideally suited for use as refrigerants and aerosol propellants. They have low bp, low viscosity, low surface tension and high density, and are non-toxic, non-flammable, odourless, chemically inert and thermally stable. The most commonly used is CF2CI2, bp, —29.8°. The market for Freons... 

FIG. 23-3 The relationship between the various flammability properties. (D. A. Cro-wl and J. F. Louvar, Chemical Process Safety Fundamentals with Applications, 2d ed, 2002. Adapted by permission of Pearson Education, Inc., Upper Saddle River, N.J.)... 

Throughout the text we will relate polymer structure to the properties of the polymer. Polymer properties are related not only to the chemical nature of the polymer, but also to such factors as extent and distribution of crystallinity, distribution of polymer chain lengths, and nature and amount of additives, such as fillers, reinforcing agents, and plasticizers, to mention a few. These factors influence essentially all the polymeric properties to some extent including hardness, flammability, weatherability, chemical stability, biological response, comfort, flex life, moisture retention, appearance, dyeability, softening point, and electrical properties. 

Chemical Properties Properties of a material that relate to toxicity, flammability, or chemical reactivity. 

Treatment of polymers containing reactive sites, such as hydroxy, carboxy or cyano groups, with sulfur tetrafluoride results in increased hydrophobic properties, chemical resistance and decreased flammability.234 236... 

The authors proposed a mechanism that accounts for the reduction in flammability properties, which depends on physical processes in the condensed phase rather than chemical reactions. Three factors are critical in determining the silica behavior during the combustion process the density and surface area of the additive, the melt viscosity of the polymer. The interplay between these factors can determine whether the silica will accumulate near the surface or sink through the polymer melt. Fumed silica and silica gel provide examples for the first case where the silica particles accumulated on the surface and formed an insulating layer that provide protection to the underlying polymer. This is in contrast to the other case where the fused silica particles sank through the polymer melt. 

A flashing flammable chemical (that possessed flammability properties similar to butane) had been manufactured in this new unit for just a few years. The liquid phase reactor had a normal liquid inventory of 13,000 gallons (59,000 L).The vertical reactor was about 9 ft. (2.74 m) in diameter and about 35 ft. (10.7 m) high and operated at about 120 psig (826 kPa gage). 

Polyetherimide Good chemical/solvent resistance, good thermal/flammability properties, inherent high color... 

The toxic, explosive, and flammable properties of some chemicals make them potential weapons in the hands of terrorists (Institute of Medicine, 2002). Many such chemicals (see Table 25.1) are commonly produced, transported, and used in large quantities in the United States. The potential for exposure is significant, and exposure to these agents can cause serious injury and... 

Chemical properties—The properties of a substance that can only be observed by the substance going through a chemical reaction, for example, flammability or chemical reactivity. 

Flammable properties of fipronil product (e.g., Term-idor SC Termiticide) flash point >93°C (199°F) flammability class will burn. Closed containers may explode (due to the build-up of pressure) when exposed to extreme heat. Suitable extinguishing media include water spray, foam, CO2, and dry chemical media. Firefighters should be equipped with self-contained breathing apparatus and turnout gear. 

The physical, chemical and hazardous properties of a number of highly toxic or flammable substances that were in the past or being currently used in the warfare have been discussed in detail in several chapters in this book. Some of these compounds are further discussed under specific chapters, such as. Sulfur Mustards, Nerve Gases, Dioxin and Related Compounds and Napalm. These and many other compounds are in most cases grouped together in this book based on their chemical structures along with their toxic or flammable properties. Presented below is a brief discussion on various types of chemicals weapons developed for military applications. Explosive substances have been omitted from this section. They are discussed separately in this book under topics such as Explosive Characteristics of Chemical Substances, Nitro Explosives, Oxidizers and Organic Peroxides and also under specific title compounds in various chapters. 

This section will cover physical properties, chemical properties, and flammability. Included in physical properties are tensile properties and dimensional stability at various temperatures in dry and moist environments, shrinkage properties, moisture uptake, and durability or wear resistance. Chemical properties cover resistance to sunlight, chemical and biological agents, and heat. The subsection on modification of properties addresses these property deficiencies and discusses progress made toward their improvement. 

Properties Light blue sol n m.w. 47.02 Toxicology Mutagen TSCA listed Precaution Flammable by chemical reaction powerful oxidizer explodes on contact with phosphorus trichloride... 

This chapter presents an overview of properties and performance of polymer blends. It is structured into nine sections dealing with aspects required for assessing the performance of a polymer blend. These are mechanical properties comprising of both low-speed and high-speed popularly studied properties chemical and solvent effects thermal and thermodynamic properties flammability electrical, optical, and sound transmission properties and some special test methods which assumed prominence recently because of their utility. 

Table 5.1.2.3 shows the chemical and flammability properties of many solvents that are commonly used in laboratories. You ll note that most of the ratings of these chemicals put them in the extremely flammable or highly flammable categories. 

Besides mechanical properties, fillers change the optical and electrical properties, chemical and weathering resistance, flammability and density of polymers. In particular, most fillers destroy optical translucency, unless their refractive index (see Table 4.4) is the same as that of the polymer. Close agreement between the fibre and the polymer refractive index is required for translucency. Feldspar has a refractive index very similar to that of several polymers and so filled, translucent products can be obtained, but it is abrasive to processing equipment. 

Chemical hoses must be designed for a specific service. Hoses are required to convey compressed gases, slurries, petroleum products, solvents, bulk chemicals, such as acids and caustics, and a full array of other chemicals that may exhibit flammable, toxic, corrosive, cryogenic, or other harsh properties. Chemical hoses are used for loading and unloading trucks, tank cars, barges, and ships. They may also operate to bypass equipment that has been taken out of service. 

Liquid phase properties Chemical composition, temperature, pH/ionic strength, viscosity, toxicity, volatility, flammability, sterility, surface tension, value... 

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