Napalm (Molecule of the Month for July 1996)
Burning Naphthene and Palmitic Acid
A variety of different chemicals can come under the title of Napalm, the major constituent of napalm is gasoline. Gasoline being a volatile, easily ignited compound, was immediately used as a weapon in war. In the First World War, both Germany and the Allies used it in flame throwers, but it burned itself too quickly to be very effective at igniting the target of the flame throwers.
In 1942 after research at Harvard University scientist found that a jelly gasoline like substance burnt slower and thus was far more effective. They found that mixing an aluminum soap powder of naphthene and palmitate (hence na-palm), also known as napthenic and palmitic acids, with gasoline produced a brownish sticky syrup that burned more slowly than raw gasoline. This new mixture of chemicals was widely used in the Second World War in flame throwers and fire bombs. Napalm bombs burned out 40% of the area of Japanese target cities in the World War.
Popular weapons continue to be developed, and napalm was no exception. With many more compounds available after World War II, a safer and just as effective napalm compound was developed. Gasoline is a pretty horrible substance, because it is extremely flammable .
The safer napalm is known as "napalm-B", super-napalm, or NP2, and it uses no napalm at all! Instead, polystyrene and benzene are used as a solvent to solidify the gasoline. Napalm B has a huge advantage over the original napalm its ignition can be well controlled. This was a great advantage to soldiers using it as there were many accidents with soldiers smoking around napalm often resulting in damage to ones own army.
There are a number of different forms of napalm B. One of these types of napalm is Fallbrook napalm. It is a mixture of 46 parts polystyrene (a polymer of styrene C6H6CH2=CH2, a short chain of the polymer is illustrated below), 33 parts gasoline and 21 parts benzene.
Formal Chemical Name (IUPAC)
Update by Karl Harrison
(Molecule of the Month for July 1996 )
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