Nonflammable polymers

Less use of flame-retardant additives and more use of reactive flame retardants and inherently nonflammable polymers... 

Nonflammable polymers, by definition, possess significant fire-resistant properties because of their chemical structure or due to some additives. All thermally stable plastics belong to the broad nonflammable plastic group, but a number of them within this group possess performance characteristics that are different. Halogenated polymers such as PVC, fluorinated polymers or those, which contain flame retardant, are classed as fire resistant. In fact, every plastic can be improved by the addition of fireproofing agents [114-118]. 

Potential health and safety problems of acryflc polymers occur in their manufacture (159). During manufacture, considerable care is exercised to reduce the potential for violent polymerizations and to reduce exposure to flammable and potentially toxic monomers and solvents. Recent environmental legislation governing air quality has resulted in completely closed ketde processes for most acryflc polymerizations. Acryflc solution polymers are treated as flammable mixtures. Dispersion polymers are nonflammable. 

Surfactants and Colloids in Supercritical Fluids Because very few nonvolatile molecules are soluble in CO2, many types of hydrophilic or lipophilic species may be dispersed in the form of polymer latexes (e.g., polystyrene), microemulsions, macroemulsions, and inorganic suspensions of metals and metal oxides (Shah et al., op. cit.). The environmentally benign, nontoxic, and nonflammable fluids water and CO2 are the two most abundant and inexpensive solvents on earth. Fluorocarbon and hydrocarbon-based surfactants have been used to form reverse micelles, water-in-C02... 

A third test often cited, Oxygen Index (O.I.) is an ASTM test which measures the flammability of the base polymers. The flammability of the polymer film may alone differ significantly from the flammability of the same polymer on a nonwoven substrate. Theoretically, the higher O.I. for a sample film, the higher its nonflammability. 

Water offers a number of important properties as a solvent for polymerization reactions. As well as its high polarity, which gives a markedly different miscibility with many monomers and polymers compared to organic solvents, it is nonflammable, nontoxic and cheap. Water also has a very high heat capacity that sustains heat exchanges in a number of very exothermic polymerizations. Largely because of these factors, polymerizations are now widely carried out in aqueous media, and, for example, more than 50% of industrial radical polymerizations are carried out in water [19]. 

Supercritical fluids have also been used purely as the solvent for polymerization reactions. Supercritical fluids have many advantages over other solvents for both the synthesis and processing of materials (see Chapter 6), and there are a number of factors that make scCCH a desirable solvent for carrying out polymerization reactions. As well as being cheap, nontoxic and nonflammable, separation of the solvent from the product is achieved simply by depressurization. This eliminates the energy-intensive drying steps that are normally required after the reaction. Carbon dioxide is also chemically relatively inert and hence can be used for a wide variety of reactions. For example, CO2 is inert towards free radicals and this can be important in polymerization reactions since there is then no chain transfer to the solvent. This means that solvent incorporation into the polymer does not take place, giving a purer material. 

The above flame retardants, HMPN and TMP, along with another commercially available alkyl phosphate, triethyl phosphate (TEP), were systematically characterized by Xu et al. To quantify the flammability of the electrolytes so that the effectiveness of these flame retardants could be compared on a more reliable basis, these authors modified a standard test UL 94 HB, intended for solid polymer samples, and measured the self-extinguishing time (SET) instead of the universally used flame propagation rate. Compared with the UL 94 HB, this new quantity is more appropriate for the evaluation of the electrolytes of low flammability, since the electrolytes that are determined to be retarded or nonflammable by this method all showed zero flame propa-... 

Uses Coolant and refrigerant herbicide and fumigant organic synthesis-methylating agent manufacturing of silicone polymers, pharmaceuticals, tetramethyl lead, synthetic rubber, methyl cellulose, agricultural chemicals and nonflammable films preparation of methylene chloride, carbon tetrachloride, chloroform low temperature solvent and extractant catalytic carrier for butyl rubber polymerization topical anesthetic fluid for thermometric and thermostatic equipment. 

The name is used both for the monomer and polymers made horn it. The polymers are usually clear oils at RT and non cracking solids at —65°F(—54°C). The typical fluoro-carhons are chemically inert, thermally stable, and nonflammable. The monomer can be prepd similarly to CFE from tribromotiifluoroethane and zinc. BFE polymers are used as flotation fluids for gyros and accelerometers used in inertial guidance systems. Can also be used as CFE (chlorotrifluoroethylene) polymers, but are more expensive Refs 1) Beil 1, 189 2) CondChemDict... 

Polyurethanes (PU s) Containing Phosphorous. Nonflammability as well as thermal stability is an important property of polymers. In the present... 

Dust explosions ignited hy static discharge are a recognized hazard encountered in the handling of polytmethyl methacrylate) powders or in the fabrication of polytmethyl methacrylatel plastic sheet. Mclhacrylic solution polymers are treated as flammable mixtures latex polymers arc nonflammable. 

A fire retardant polymer that is easily impregnated into wood to petrify the material, making it stronger and nonflammable. 

The benefits that scC02 offers as a reaction medium have been the object of intense research activity, and it is foreseeable that this field of study will continue to improve. This suggestion is justified by the fact that scC02 demonstrates both favorable physico-chemical properties (tunability of the chemico-physical properties, complete miscibility with permanent gases, plasticizing effect of polymers, inertness to free chain reactions) and positive technical and environmental qualities (naturally occurring and abundant, inexpensive, nontoxic, nonflammable). 

Creating the polymers which can be the basis of nonflammable materials with a required set of technical characteristrics. 

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