The Combustion of Polymers

1562 WordsJun 25, 20187 Pages
Introduction The history of polymers stretch back millions of years. These “primitive” polymers were created by nature to fulfill the needs of information storage, energy storage and information reproduction. Human made polymers are a more recent invention, of the last two hundred years or so. These polymers are general made of highly flammable hydrocarbons and their derivatives. Fires caused by a combination of human careless and the physical properties of hydrocarbons have caused millions of dollars in property damage and claimed an untold number of human lives. It is this fact that has lead to scientists devoting time and resources to making polymers safer. In the following paragraphs the mechanism behind burning polymers will be…show more content…
This dehydrates the polymer, forming the protective carbon layer. At higher temperatures the phosphoric acid can help in the generation of cross linked species and can under go polymerization to form polyphosphates. Which react with the cross linked species to form the char layer. Borated species work the same way, they form a glassy surface that helps protect and insulate the substrate. The final pathway that will be investigated is the suppression of radical species in the reaction space. This is done by introducing halogenated hydrocarbons and an inorganic “enhancer” into the polymer. When the polymer burns, halogen radicals are released into the gas phase. The halogen reacts with hydrogen, to form a hydrogen halide. Finally, this species reacts with either hydrogen or oxygen radical to form hydrogen gas or water vapor, respectfully. From this series of reactions the halogen radical is regenerated, where it reacts with either the polymer substrate or more gaseous hydrogen to form hydrogen halide. The halogen radicals are at a lower energy than either the hydrogen or oxygen radical species. The effectiveness of this method is dependent on the halogen used. Bromine is the most common due to it narrow temperature activation range. Chlorine is the next most common but due to a broad temperature range is not as useful. Florine and
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