Stearine covered Aluminium

[mabuse00]

Hi,

 

I just came across some flake aluminium wich is covered with stearine.

 

How will the stearine affect the behaviour? Has it any negative effect?

 

What one is more reactive, stearine covered flake or atomised/spherical aluminium?

 

 

I've tried some white and silver stars with atomised stuff, the were very hard to light.

Some thermite experiments where not very succesfull either, unless I added some magnesium (to fast ).

[Mumbles]

The stearin should be just fine. Most, if not all, flake aluminums are covered in stearine or another fatty acid. They're designed into the formulas to work that way. The flakes, even though coated, are typically more reactive on a similar size scale. High metal stars, regardless if they are flake or atomized, are typically rather difficult to ignite.

[mabuse00]

Thank you,

thats all I wanted to know

Edited January 18, 2011 by mabuse00

[pyrogeorge]

why aluminium wich is covered with stearine is difficult to make hard stars?i made bright silver pump stars 12mm and it looks that is difficult to bind the stars..i think that stearine is the problem.

what do you think?

[Mumbles]

Compositions which are high in bright aluminum typically don't preform properly with conventional binders. This is partly due to the stearine being hydrophobic, and partly due to the lack of density of the aluminum. The secret to binding high aluminum stars is to use thin wheat paste instead of water, typically in addition to the dextrin or SGRS. Warm paste and 1 little bit of alcohol helps too.