Plastics, burning mechanism

Plastic flavor Wax-like odor Alcohol, sweet chemical, plastic, bitter, mechanical, glue, burning, spicy, fruity, almond,rotten swampy, burning plastic pipe... 

Styrene (ethenylbenzene) Polystyrene, plastic, burning plastic, styrene. <0.005 Not detectable in normal beer 0.02 Off-flavor produced by contaminant wild yeast during fermentation or a taint from raw materials/packaging. (Styrene has a mechanism of production similar to those of traditional wheat beer phenolics. Related to the POP phenolic off-flavor gene, it may he found in bottle re-fermented beers if POP and strains are present (Schwarz, 2012)). 

Cnd-of-life options for plastics are important factors that influence the life cycle assessment (LCA) of plastics. Disposal options for plastics are to mechanically recycle the plastic, chemically recycle the plastic, compost the biobased plastic, burn the plastic into energy, or bury the plastic in a landfill. 

The Standard for Tests for Flammability of Plastic Materials for Parts in Devices and Appliances (UL 94) has methods for determining whether a material will extinguish, or burn and propagate flame. The UL Standard for Polymeric Materials-ShortTerm Property Evaluations is a series of small-scale tests used as a basis for comparing the mechanical, electrical, thermal, and resistance-to-ignition characteristics of materials. 

The key to the successful application of high performance, pourable nitrocellulose plastisols lies in a reasonably priced, high quality source of fine-particle, at least partially colloided, spheroidal nitrocellulose. Here we are speaking of particles much finer than the well-known ball powder, produced by the Olin Mathieson Chemical Co. for small arms for over 30 years (7). Actually, particles on the order of 5-50/x diameter appear to be required to assure a reasonable continuum of uniformly plasticized nitrocellulose binder in a propellant containing 45% or more of combined crystalline oxidizer and powdered metal fuel. Such a continuum of binder is necessary to assure acceptable mechanical properties and reproducible burning characteristics of the finished propellant. Preincorporation of a certain content of the water-insoluble solids within the nitrocellulose microspheres is an effective means of helping to assure this continuum of binder and alleviates the requirements for extremely small ball size. The use of a total of 45% or more of crystalline oxidizer and (generally) metal fuel is essential if the propellant is to be competitive with other modern propellants now in service. 

In addition to fuel, oxidizer and inert/energetic plasticizer, various additives are also included in the propellant formulations in order to improve their mechanical or ballistic properties. One such additive is termed a burn-rate (ballistic) modifier which alters inherently high dependence of the burn rate on chamber pressure. The use of an additive for this purpose depends on the type of propellant, that is,... 

In general, all types of solid plastic or glass-reinforced plastic pipe should not be used, if possible, with flammable liquids. Compared to metal, plastic piping melts and burns easier, is more fragile, is easily mechanically damaged, is harder to adequately support, and should be used with appropriate judgement. 

Mechanical working of a metal is plastic deformation performed to change dimensions, properties, and/or surface conditions. Plastic deformation below the rectys-tallization temperature is called cold working. Plastic deformation above the recrystallization temperature, but below the melting or burning point, is called hot working. 

The mechanism of burning for polymers is believed to take place through thermal pyrolysis of the solid plastic to produce gases that act as fuel for the fire (45). Fire retardants work in both the condensed and the vapor phase to interrupt melting of the polymer and burning of the gases. Triaryl phosphates function well in the vapor phase. Alkyl aryl phosphates are believed to decompose in the flame front to form polyphosphoric acid, which stays in the condensed phase to form char, which reduces flammability and smoke evolution (46. 47). 

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