Burning rate of plastics

Burning Rates of Plastics The Small B Assumption and Radiation Effects... 

Quintiere, J. G. and McCaffrey, B. J., The Burning Rate of Wood and Plastic Cribs in an Enclosure, Vol. 1, NBSIR 80-2054, National Bureau of Standards, Gaithersburg, Maryland, November 1980. 

CA, not found [Suggested is the use of the copolymers as binder for solid proplnt compns and as a means of increasing the burning rate of solid proplnts. For example, butadiene/vinyl ferrocene copolymer binder (10.0), isodecyl pelargonate plasticizer (10.0), Al powder (10.0) and AP (70 wt %) are mixed to form a proplnt... 

Experimental procedures for detn of burning rates of rocket proplnts are practically identical with those described under "Burning and Burning Characteristics of Propellants for Artillery Weapons and Small Arms The method described by Warren(Ref 25,PP 90-1) uses a modified Crawshaw strand-burning apparatus. This method is used with solid strands ca 1/8 in diam and 7 long and which are coated with a plastic so that they burn from one end only... 

In both explosives and propellants the materials are relatively non-porous. The binders and plasticizers used effectively fill the pore spaces. Pyrotechnics are porous and the heat transfer related to the hot gas permeation into the reactant material mixture becomes important. In many pyrotechnics no binders or plasticizers are used. The explosives and propellants have burning (or detonation) rates that depend on density, temperature, and pressure. However, the burning rates of pyrotechnics are, in addition, affected by porosity, particle sizes, purity, homogeneity (degree of mixing), and stoichiometry (fuel or oxidizer ratio). 

A compn useful as a propellant Is derived from a mixture., with plasticized NC of dry potassium chlorate impregnated with Manila copal resin and of dry potassium chlorate/ charcoal impregnated With a gas oline-paraffin distillate. Burning rate of the grains obtained by extrusion or sheeting/cutting is controlled by the amount of chlorate-resin present Ref s.j. McClung, USP 2483589(1949) ... 

FRs are chemicals that can inhibit ignition and/or reduce the burning rate of a product. These are often used by manufacturers to help them meet fire safety standards set down by law for products such as electrical equipment, furnishings, and vehicles. These compounds are added to polymers, paint, textiles, and other materials to improve their fireproof properties. The main applications are in plastic housings of electronic products such as TV sets and computers, car parts, circuit boards, electric components, and cables. There are currently over 100 different substances used as FRs and these can be classihed in four categories (Figure 31.1) ... 

Guan H, Liu Y et al (2007) Study on decreasing the burning rate of nitrate ester plasticized polyether propellant J Propul Technol 28(2) 216-219... 

In a test procedure of this type, the burning rate was determined as a function of temperature. The results of such an experiment are shown in Figure 3.52. The data are fairly reproducible for plastics but show a considerable scatter for wood samples since plastic specimens burn as a bulk while the flame travels along the surface of the wood rods without combustion of the core of the specimen. (The theoretical aspects of flame spread rate of plastics are thoroughly discussed in Section 2.4.5.3.)... 

D5025-94 Standard Specification for a Laboratory Burner Used for Small-Scale Burning Tests on Plastics Materials D5045-96 Standard Test Methods for Plane-Strain Fracture Toughness and Strain Energy Release Rate of Plastic Materials... 

ASTM D635, Test Methodfor Rate of Burning andj or Extent and Time of Burning of Self-Supporting Plastics in a Hori yontal Position, Vol. 8.01, ASTM, Philadelphia, Pa., 1991. 

No data Ignition Temperature No data Electrical Hazard No data Burning Rate No data. Cheoiical Reactivity - Reactivity with Water. No reaction Reactivity with Common Materials May attack some forms of plastics Stability During Transport Stable Neutralizing Agents for Acids and Caustics Stable Polymerization Not pertinent Inhibitor of Polymerization Not pertinent. 

Some materials may bum quite slowly but may propagate a flame rapidly over their surfaces. Thin wood paneling will burn readily, yet a heavy timber post will sustain a fire on its surface until it is charred, then smolder at a remarkably slow rate of burning. Bituminous materials may spread a fire by softening and running down a wall. Steel of course does not burn, but is catastrophically weakened by the elevated temperatures of a fire. PVC does not bum, but it softens at relatively low temperatures. Other plastics may not burn readily but still emit copious amounts of smoke. And some flammable plastics, such as... 

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