H.W Help

[DIYMark]

Hi all,

 

Im working on a chemistry report and I'm doing one on the science behind star compositions . Ive done all of it but for a bit extra I was hoping to add a paragrpah about glitter stars.

 

Problem is that google showed up nothing so I was wondering if anyone here knows why glitter stars work like they do?

[mormanman]

LINK

Its the glitter theory. I've never read it just b/c I didn't want to but I mean if you need it its there. I hope it helps.

[Frozentech]

Hi all,

 

Im working on a chemistry report and I'm doing one on the science behind star compositions . Ive done all of it but for a bit extra I was hoping to add a paragrpah about glitter stars.

 

Problem is that google showed up nothing   so I was wondering if anyone here knows why glitter stars work like they do?

Bob Winokur and Lloyd Scott Oglesby are the guys you need to look at. Between the two of them, they pretty well wrote the books on glitter. You'd need to reference the actual publications for a paper, but both are still in print ( or available from the usual pyro sources )

 

Robert M. Winokur: The pyrotechnic phenomenon of glitter, Pyrotechnica, No.2, February, 1978

 

Lloyd Scott Oglesby: Glitter, the Chemistry and Technique, 1983

 

Takeo Shimizu: Investigation of the Pyrotechnic Glitter Phenomenon-Part I&II, Pyrotechnica XIV, August 1992

[Mumbles]

You know, the more I read on pyro guide, the less I am a fan of it. That was the biggest load of bullshit and simply erroneous statements I have ever read. It seems to me they very briefly skimmed Oglesby's text, never actually read it, and just made up the parts they couldn't remember.

 

This is just a brief overview, but it might be of some help.

 

The glitter effect is a series of complex interactions. It is thought to be primarily produced by the expulsion of molten droplets of metal covered in a semi-viscous slag, which reacts with the metal after a delay producing a flash in the tail. The entire molten droplet that falls behind is often referred to as a "spritzel". The delay depends primarily on the viscosity of the slag, size of the droplet, along with a few other complex interactions that are not entirely understood. The slag is primarily composed of molten potassium sulfide and polysulfides. Certain additives, such as antimony trisulfide, change the composition of the slag. Whereas others, such as carbonates, are thought to simply make the slag less fluid by integrating solid particles. Both are generally thought to lengthen the delay between ejection and the flash.

 

There is a lot of other stuff to consider, such as MgAl, Barium nitrate, size of Al, catalysts, but that would take an entire book to go over. For a more complex and more thorough explanation I second Frozentech's book suggestions. They really are excellent reading.

[DIYMark]

Thank you for your help guys. There really is more to glitter than I thought Well, in my paper Ill add a section about the theory of how glitter works just as a bit of extra info. Once again, thanks.

[mormanman]

Thanks Mumbles, that was interesting.

[flying fish]

This is how I had always thought of it, but it may not be correct, and is probably a very simplified view even if it is correct (that is why I am asking!):

 

I've always thought that they delay agent suppresses the metal from burning when the glitter droplet is first expelled from the star. Then once the delay agent has burned off or otherwise somehow separated from the rest of the expelled droplet of glitter, you get a flash. My impression was that this was made possible by the fact that the nitrate/metal powder had a higher ignition temperature compared to the nitrate/charcoal. So once the delay agent separates out or burns off, the temp goes high enough to ignite the aluminum or magnalium and create a flash.

 

Does this sound feasible, or is it a bunch of nonsense? I honestly can't remember where I initially heard this explanation (or whether I dreamt it up for that matter)!