Is 96/4% AL/Shellac any good?

[kababz]

I've been having trouble geting pure Al powder, and recently I saw this art and painting store selling Aluminum "pigments" (400/1000/1200 mesh).
I asked the dude wheater this is pure AL powder and he said- "no its a mixture of 96% pure Al powder, and (4%) shellac to help it fit together with the other stuff"

the question is, wont these 4% mess up my intire mixture, and decrease the mixture's powder significantly like if I make Flash powder from it (by power I mean the heat, noise, propellant ext. generated when ignited)

[Jacks Complete]

Since shellac is a fuel too, I don't see that it would cause much of an issue as long as it was set to shape before it dried out.

Anyone else?

You can make your own Al powder, there are several threads on it. Probably worth doing if you want more than a little of it.

Also, please check your spelling/typos.

[nbk2000]

Removal of the shellac with solvents and collecting the aluminum powder by sedimentation sounds better than using it straight. The shellac could form a coating over the particles that might impede ignition.

[Bert]

Is this product a powder, a paste, gell, liquid paint or what? If it's not a powder, what is the liquid? Alcohol?

[lucas]

Shellac makes a good binder for star formulations. It is soluble in ethanol. Black powder is conveniently bound with shellac to make hard stars. If the Aluminium were to be used in a star composition then this would be an ideal product to use.

For salutes and fast burning mixtures, it may be that the particle shape is more important than the coating. Paint aluminium is likely to be spherical and hence slower burning than flake. In this case the coating will probably be less relevent than the shape. It's still likely to work fine, but be slightly slower to ignite. Spherical aluminium works in flash salutes but needs the confinement to be better than flake in order to transition from a fast burning flash to explosion.

[justme]

I believe that what you have found could be quite good for pyro uses if the shellac is dissolved from the pigment first.

I would not be too concerned about the shellac coating the grains, but rather think that the shellac could act as a binder and inhibit any attempt to mix the material into a composition.

I have not seen the material, but assume that you will find that it is a paste, wet with alcohol or another solvent, and designed to be added to other materials like resins to form a metallic paint.

Aluminum paint pigment is not spherical, and indeed is the desired flake material, see: http://www.protek-usa.com/AluminumPigments.html for a discussion including photographs.

Denatured alcohol is the classic solvent for shellac, but household ammonia at full strength is actually better to get it off of hands and brushes.

I don't think that you would want to use it on the aluminum though, since the ammonia will dissolve the protective oxide coat if not the aluminum itself. Think in terms of a runaway reaction and Hydrogen evolution.