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Author: Subject: PTFE Magnesium thermite fun
malford
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 Quote: Originally posted by IndependentBoffin My thermochemistry is a bit rusty (last did the sums more than a decade ago) but here are the reaction calculations. Please feel free to correct me if you spot a mistake. Overall equation: 2Mg + (C2F4n -> 2MgF2 + 2C Mg + F2 -> MgF2 ................................ ΔHf = -1124 kJ/mole 2C + 2F2 -> -(C2F4n- ................................ ΔHf = -832.6kJ/mole Heat of reaction = 832.6 - 2×1124 = -1416 kJ for 2 moles of Mg and 1 mole of (C2F4n. Because I am an engineer and tend to think in terms of specific energy this gives 1416/(2×12 + 4×19 + 2×24.31)kJ/g or 9.526 kJ/g of reactants.

As you can see in the chart, regular flash powder ranks high with -10.59 kJ/g, but more importantly for munitions -27.38 kJ/cm3. To slow the reaction of flash powder, one can use dissolved nitrocellulose as a binder. This makes for a spectacular igniter.
Zyklon-A
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I know this has been dead for a while, but I here is a good read on the subject:

Attachment: (MTV-1) Magnesium-Teflon-Viton Pyrotechnic Compositions.pdf (1.8MB)