23 replies to this topic

[Mumbles]

I checked the chemical list here. It says that stearic acid is "hungry" for oxygen, so it seems to be a powerful fuel, although "cool" in temperature. It's pretty common in many old blue compositions and in some green.

Stearin is like the hexamine of old times. It functions in similar ways of cooling the flame and expanding the flame envelope. Some feel more comfortable using stearin with chlorate stars instead of hexamine due to the worry for hydrolysis to various methylamines (fishy odor). It also lubricates stars and can make them easier to pump.

[Potassiumchlorate]

I always thought that the greatest risk was the formation of ammonium chlorate, since hexamine is produced by reacting formaldehyde and ammonia.

I tried one star in my star gun, but it didn't ignite, so I lit one on the ground. At a distance of about 15 meters it seemed perfectly deep blue, but maybe that is too close, considering that it will be 10 times higher up when fired in a 5" shell.

Edited by Potassiumchlorate, 28 February 2012 - 02:42 PM.

[Potassiumchlorate]

Update: since I found out that my colophony resin is of the inferior light type I simply use red gum instead. Now I also have stearin granules. For a 10g test batch I simply mix everything with a wooden spoon first (crushing the stearin granules with the spoon while mixing), then screen it three times through a 120 mesh sieve, spray 1g of water/alcohol on it and make pumped stars.

Thus the changed composition is:

Potassium chlorate 64
Copper oxychloride 19
Chlorowax 5
Red gum 5
Stearin 2
Dextrin 5

Chlorowax is very interesting. It doesn't burn very easily mixed with potassium chlorate only, but once it does, the burning is fierceful and the smell of chlorine is very strong. My very unscientific opinion is that this is a very good chlorine donor.

Edited by Potassiumchlorate, 03 May 2012 - 04:47 PM.

[Potassiumchlorate]

Tested one on the ground and one in my stargun. No video. The star on the ground burned surprisingly hot. The gravel where I burned it was very hot afterwards, almost as when burning a metallic star. Some black residue, not much. The one shot from the stargun burned with a bright blue flame.