Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: Flare Paste/Gelled Flashpowder
James Ikanov
Hazard to Self
**




Posts: 81
Registered: 12-7-2015
Location: Alaska
Member Is Offline

Mood: Zen

smile.gif posted on 16-2-2016 at 21:34
Flare Paste/Gelled Flashpowder


Over the course of a bit of, frankly, screwing around, I think I've found something rather interesting. I was initially attempting to make a sprengel explosive out of stoichiometric mixture of glycerin and KClO4, but my results did not yield anything explosive. I actually found my mixture to be less than flammable. So I decided to mix in flashpowder (also stoichiometric), and simply use my paste as a binder.

I did a flame test in the open, unconfined, and I found that it burns exactly like flashpowder... just much, much slower. Even slower than many thermites I've tried. The mixture burns visibly purple, and quite bright.

A few minutes ago, I performed my first test with gentle confinement (a cardboard tube with an open top) and it burns with quite a lot of smoke and bright flame. It very much requires a tinted lense to avoid blindness, and when partially confined it is prone to popping and gently tossing globs of molten aluminum a few inches or millimeters into the air.

I prepared it by mixing 11 parts glycerin (by weight) to 26 parts KClO4. After these were fully mixed, I added 20 grams of stoichiometric flashpowder (7 parts KClO4 to 3 parts german dark aluminum)

My best theory at this point is that by filling the void spaces that would otherwise be present, the flashpowder does not deflagrate at the rate it otherwise would, and still manages to generate enough energy and xygen to fully burn the glycerin.

The only discouraging aspect to this is that I have been unable to ignite it with anything less than a blowtorch. I have yet to test it confined with fuse, however.

Overall, it seems more a novelty than anything practical, but I wonder if anyone has experimented with anything similar?





“To do good work one must eat well, be well housed, have one's fling from time to time, smoke one's pipe, and drink one's coffee in peace” - Vincent Van Gogh
View user's profile View All Posts By User
Detonationology
National Hazard
****




Posts: 362
Registered: 5-5-2015
Location: Deep South
Member Is Offline

Mood: Electrophillic

[*] posted on 16-2-2016 at 21:54


Why add glycerin? It's well accepted that unconfined flash powder detonates at a higher velocity than when confined. In low concentrations, most oxidizers are useless when combined with liquid fuels. The oxidizer is typically not fully in homogenized throughout the fuel, which prevents efficient combustion. The oxidizer must make up the majority of the composition for their to be any chance of it working, with only a small amount to liquid fuel. ANFO is a low velocity mixture, composed of about 95% AN: 5% petrol. The explosive nature of the mixture mostly relies on the fact that the AN is extremely sensitive when impurities are present, and not so much on the liquid fuel.



“There are no differences but differences of degree between different degrees of difference and no difference.” ― William James
View user's profile View All Posts By User
James Ikanov
Hazard to Self
**




Posts: 81
Registered: 12-7-2015
Location: Alaska
Member Is Offline

Mood: Zen

[*] posted on 16-2-2016 at 22:04


This is true. I considered that the initial go round at attempting to make a sprengel was hindered by the fact that my perchlorate was clumped in some areas, so I added slightly more glycerin to attempt to dissolve the perchlorate more evenly in it. No dice.

Aside from that, the goal was to get something that was easily manipulated and moldable. It partially succeeded; the mixture is colloidal and fairly sticky. In fact, it can be applied to many surfaces much like paint, but such a thin coating does not reliably propagate combustion in the ratios I used. It does however, pour somewhat neatly into casings.

I was unaware that unconfined flashpowder detonated at a higher velocity than confined, but I suppose that makes sense if the gases it generates are superheated atmospheric gasses?

I was always under the impression that AN was actually rather stable, but regardless, I was simply curious to see if anyone else had used a similar mixture. I am by no means an expert, I simply found this amusing and worth sharing.

EDIT: Oh, and a word of warning if someone else attempts this. It is very much thick and gooey enough to break a glass stir rod. Learned that the hard way.

[Edited on 17-2-2016 by James Ikanov]




“To do good work one must eat well, be well housed, have one's fling from time to time, smoke one's pipe, and drink one's coffee in peace” - Vincent Van Gogh
View user's profile View All Posts By User
Bert
Super Administrator
Thread Moved
17-2-2016 at 05:31
PHILOU Zrealone
International Hazard
*****




Posts: 2879
Registered: 20-5-2002
Location: Brussel
Member Is Offline

Mood: Bis-diazo-dinitro-hydroquinonic

[*] posted on 22-2-2016 at 07:45


This was posted by Nitro-genes into the Energetic material section...
Pyrotechnic burster composition US 6521064 B1

It exposes the use of flash powder with pentaerythritol or terephtalic acid as safe and powerful mixes exploding with violence when confined.
Freepatents online USP 6521064
download the pdf

Since glycerol is related to PE the explanation for the unsensitivity of your mix may be identical...low boiling/vaporisation temperature...tempering the exotherm, but once a limit is surpassed due to confinement, then full power express...




PH Z (PHILOU Zrealone)

"Physic is all what never works; Chemistry is all what stinks and explodes!"-"Life that deadly disease, sexually transmitted."(W.Allen)
View user's profile View All Posts By User
feacetech
Hazard to Others
***




Posts: 163
Registered: 12-2-2007
Member Is Offline

Mood: No Mood

[*] posted on 24-2-2016 at 17:59


Have your tried igniting it with a little KMnO4

or KMnO4 and glycerine
View user's profile View All Posts By User
James Ikanov
Hazard to Self
**




Posts: 81
Registered: 12-7-2015
Location: Alaska
Member Is Offline

Mood: Zen

[*] posted on 8-3-2016 at 09:39


Nope. I don't have any KMnO4 sitting around, just some dirty MnO2. I might see if I can get some potassium hydroxide and make some to test that, however. I usually get a small sample and test one on concrete, and one on an elevated steel platform with a blowtorch, but I don't think it would be quite as hot as that particular mixture.


Also, thank you for the patent, PHILOU Zrealone. It was highly informative, and another batch I ended up testing (a 1:1:1 mixture by weight) displayed very similar properties! placing some of it on paper and then rolling it around it provided enough confinement to get little pockets of deflagration very readily, although not as easy to light as "dry" flashpowder. Downside being it was also very inconsistent in how well it deflagrated under such light confinement.




“To do good work one must eat well, be well housed, have one's fling from time to time, smoke one's pipe, and drink one's coffee in peace” - Vincent Van Gogh
View user's profile View All Posts By User

  Go To Top