In search of opinions...APWAX?

[MightyQuinn®]

Call me crazy, but here goes.

I have done the searches and read a ton, the mods can track my progress I am sure. :D I am not finding precisely what I am looking for. I may need a lesson in optimum use of the proffered search feature so for obvious reasons, I am depositing this in the 'cooler'.

I find a number of topics relating to ANWAX and it's various derivatives and some vaguely on topic information relating to soft or gelled waxes.

I would like opinions on the viability of saturating the gel wax with as much AP as it can take. I then have ideas to use this as a booster under the guise that AP will be much less volatile (theoretically) suspended in a buffer gel. I also am theorizing that an AP booster may have a longer shelf life in this configuration. Furthermore, at lower temperatures the wax is more solid and less prone to shifting adding another theoretical layer of 'protection'.

Could this increase the shockwave having no air voids? Could the wax detonate or just deflagrate?

1g AP cap -->20g APWAX booster -->(whatever you choose)

All this theorizing depends on the solubility of AP in the gel wax. I have read over the patent information, but it's over my head. I'll be the first to admit I am no letter-laden scientist so my knowledge is VERY limited in chemistry. I know there are learned souls here that could make mincemeat of my theories and I am prepared for it.

I am also aware that there are other forms of material to be used as boosters, but it will take some experience before I attempt anything more intense than AP at this time.


The following is quoted from the patent: United States Patent 5,879,694 (http://patft.uspto.gov/netacgi/nph-Parser?Sect1=PTO1&Sect2=HITOFF&d=PALL&p=1&u=/netahtml/srchnum.htm&r=1&f=G&l=50&s1=5,879,694.WKU.&OS=PN/5,879,694&RS=PN/5,879,694)

....
Transparent stiff gel candles comprising a hydrocarbon oil, a wick, and one or more triblock, radial block or multiblock copolymer of a thermoplastic rubber, and optionally a diblock copolymer.


An article of manufacture comprising a candle, said candle consisting essentially of a gel consisting essentially of from about 70% to about 98% by weight of a hydrocarbon oil, and from about 2% to about 30% by weight of a triblock copolymer, and having a wick in said gel, and said candle optionally containing one or more additives selected from the group consisting of an antioxidant, stabilizer, fragrance, colorant, insect repellent, and flame retardant.

This invention relates to candles in the form of firm gels, and more particularly to stiff heterophase, thermally reversible mineral oil gels, preferably white oil gels. The candles of the invention contain block copolymers and blends thereof, the copolymers being preferably derived from styrene-rubber block units. The candles are naturally transparent and uncolored. Optionally, the candles may be colored with one or more colors, and may contain embedded and/or external ornamental features, as well as fragrances and functional additives.

Any input is welcome.

[THErAPIST]

I've plasticised AP with wax many times when i still experimented. From what I've found the oily, soft- wax is the best kind of wax to use. The gel kind of wax has to be heated for it to be in a liquid state... if its not heated it's like gelatin. If you try to kneed the gelatin kind of wax it just breaks into clumps, it wont hold any AP unless its heated up and dripped onto the AP... which of course isnt the greatest of ideas. The seemingly oil based soft wax is easy to use, AP and the wax are kneeded together slowly with gloved hands. The ap doesnt dissolve or anything. While density may be higher, the individual crystals are insulated and cussioned from each other so velocity is a bit lower. If too much AP is mixed in the wax won't even hold together and it just crumbles appart.

Velocity can be made a tad higher if something like NC is added, but then there has to be a balance where theres enough AP in the wax to detonate the NC, but not so much AP or NC (or both) so that the wax gets crumbly.

It's extremely easy to set off though, which is a good thing, and if its warm outside you can stick it to things. If its cold outside, if you kneed it enough to warm it up a buit it sticks to things even better. A blasting cap can be as small as .25g pressed into a drinking straw (in my experiments). Upon detonation there is a bit of smoke, and instead of a boom the noise is more of a hollow sounding pop/bang.

It is easier, and SLIGHTLY safer to store, but it contains AP so storage isn't a good idea. DDNP would be much better suited for this application. Wax is also an alright way to help bulk out a booster charge

[matjaz]

MightyQueen,
my experimental dreams on apwax were never very successful. If I used too much wax, it just burnt fiercely, much like BP. With little wax it does detonate but loses the consistence of putty and falls apart.

Every possible AP/wax mix I tried was way less brisant than pressed AP (tested on a steel witness plate). It was probably more resistant to mechanical ignition, though. I was surprised, too, since I assumed that the wax filled empty space should help propagate the shockwave.

[Dave Angel]

It might be worth while looking into the use of liquid beeswax. The product I bought contained 80% volatile hydrocarbons, I think it was the wax dissolved in kerosene so it can probably be replicated cheaply.

You could easily mix the AP in with this and allow the volatiles to evaporate, though how hard the resulting product will be will naturally depend on the particular wax. My wax was quite hard after the volatiles had evaporated, but then it was in an unheated room in winter. At room temperature it became softer and could possibly be acceptable for your purposes.

[hinz]

I think it won't work, because AP has a low oxygen balance(something arround -150%) . If you add wax,(witch contains H and C atoms) you will lower the oxygen balance. If the oxygen balance is too low, your APWAX won't detonate, it will burn. It's because your APWAX need the oxygen of the air.

[kddflx]

If the oxygen balance is too low, your APWAX won't detonate, it will burn. It's because your APWAX need the oxygen of the air.


... Are you saying that if an explosive's oxygen balance is too low it wont detonate but will only burn? What about explosives like lead azide? .. I dont even know how one'd go about finding the OB of that...

On second thought, I always thought a detonation was just the explosive burning with atoms within the molecule extreemly fast. So aren't all detonations burnings? :p

Learn to use the board features properly, eh? ;)

[metafractal]

No, hinz is correct. I'm surprised someone didn't bring this up earlier --
Acetone Peroxide is already highly oxygen deficient, and to add a hydrocarbon to it will kill its power if it doesn't make it undetonable.
But rather than speculate, I'll do some calculations:
AP on its own requires ten and a half moles of oxygen from the atmosphere to detonate:

C9H18O6 + 10.5O2 ---> 9CO2 + 9H2O

Lets say you add an equal proportion by weight of wax to the AP. For simplicity, call the wax a longish hydrocarbon, like C20H42. This means that you are adding about 0.8 moles of wax per mole of AP (mw(AP)/mw(Wax)).

C9H18O6 + 0.8C20H42 + 38O2 ---> 25CO2 + 26H2O

For the same weight of waxed AP, 38 mol of oxygen is now required. That's 3.6 times as much! The power in an explosive lies in its being able to quickly recombine into lower-energy products. But, now the AP must wait for more oxygen from the atmosphere to enter the area before it can recombine(sp?). Ideal explosives (like EGDN) require ZERO moles of oxygen to detonate, as the molecule supplies it all itself.

Detonation is not burning, either. It is a distinctly different process which involves shockwave disassociation of molecules and recombination into lower-energy molecules, often in combination with oxygen, to release large amounts of energy quickly. Lead azide is a non-oxidative explosive, and so oxygen ballance is not applicable to it.
You *could* add an oxidizer to better (albeit not correct) this situation, but I hate the idea of kneeding explosive organic peroxides in the first place, let alone adding a sensitizer to it and kneeding it.
Just use AP with nitrocellulose , like everyone does. Using an energetic binder helps the OB, instead of making it worse. The more nitrated the cellulose is, the better, but ping-pong plastic works just fine.

[Anthony]

If acetone peroxide requires atmospheric oxygen to detonate, why will it happily detonate in a sealed container (e.g blasting cap), or underwater?

[kddflx]

I think there may be a mis-understanding here about the wax. Is the wax a filler or an actual component of the detonation reaction?

Metalfractal, I thank you for clarifing detonation mechanics to me, and I have to agree that the math is correct. However, the math doesn't apply here if the wax doesn't even detonate...

I mean, not only have I never heard of wax being combustible in the detonation sense, but the purpose of the wax isn't properly defined here. Is it a binder? Or maybe a desensitizer? I think I saw in a thread a while ago that somebody added Baking Soda as a filler with AP. It was dismissed because although it did stretch the suply, it didn't really make a difference in it's performance(although it would probably reduce the brissancy because the energy would be spent moving the Soda).

Relating back to the first post, I say that the wax is like the baking soda of the mentioned post, it justs sit there in the mix, only changing the physical properties of the AP mix.

[xyz]

The wax is a binder and also helps to cushion the AP crystals against shock, desensitizing the AP.

Due to the fact that AP is already oxygen deficient, the wax does not get involved in the detonation. (But if an explosive with excess oxygen was used then yes it would, like in the case of ANWAX)

Baking soda or other fillers are sometimes added to AP to "cut" it so that you get more, this is usually only used for salutes as "cut" detonators will be very unreliable. Personally I would avoid baking soda due to it's alkalinity, AP likes to have a neutral pH and acids/bases sensitize it. I use KNO3, which I have found actually seems to increase the noise and destructive capability of the salutes. I use 25% AP and 75% fine KNO3 powder if anyone is interested. I hypothesise that the KNO3 increases the power because it provides the extra oxygen that the AP needs to detonate. I once did an OB calculation on the mixture and IIRC a 25/75 mix was almost perfect.

I would however consider this mixture unsuitable for detonators as although it seems to be more powerful, it is noticeably less brisant (it makes a loud bang instead of a sharp crack like straight AP) and would therefore not initiate seconday explosives reliably.

Sorry, I got a little off topic describing the APPN mix, but I hope the first part of my post can clear things up

[metafractal]

Thanks for clarifying that xyz. I had just assumed that anyithing intimately mixed with a high explosive would detonate. I'm sure that some of it detonates, but your probably right in saying that most of it doesn't. Nonetheless, it is still certain that adding a wax to AP will decrease its power. After all, the wax certianly does not stay in hydrocarbon form - it still ends up H2O and CO2, only not by detonation, apparently. This just means that the combustion of the wax releases even less energy than if it were to detonate with the AP. Or am I confusing myself and everyone else?
How does AP detonate in a closed space? Hmmm... Well, I assume (though this is pure speculation) that it goes something like this:
1. AP comes into contact with flame
2. AP is able to undergo DDT with the oxygen it supplies itself
3. Shockwave ruptures container, and AP is in contact with the atmosphere before the detonation has completed OR the deflagration of AP before the DDT ruptures the container.

[Anthony]

And if the charge is completely submerged underwater, and never breaks the surface?

Are we sure that oxygen-deficient explosives don't simply produce less oxidised by-products? E.g carbon monoxide, rather than carbon dioxide, etc

[xyz]

I'm with Anthony on this one, an oxygen deficient explosive produces less-oxidised products upon detonation. There are cases where these products will be hot enough to continue oxidising using atmospheric oxygen (such as the dirty black fireballs created by large charges of straight TNT), but I don't think AP is one of these cases.

1. AP doesn't produce all that much heat when it detonates, and it is used in small (a few grams) charges by everyone who values their safety. These things reduce the heat of the detonation products and therefore the possibility of the detonation products reacting with atmospheric oxygen.

2. Atmospheric oxidation of detonation products usually causes a bright flash. No flash can be observed from AP detonating, even in total darkness.

As for wax reducing the power of AP, I would say that yes, wax would reduce the power of AP. I don't think it has anything to do with the wax being involved in the detonation though, rather the all energy required to vaporise the wax.

[nbk2000]

But the vaporized hydrocarbon (wax) may provide a secondary fuel source once it's dispersed and ignited by the AP. A weak-ass FAE to be sure, but still...

A sizeable enough test (kilo) in an enclosed concrete structure would provide a comparative basis for temperatures, as you could explode it with targets like clothes/hair/materials and see which gets more burnt.

[xyz]

Yes, the wax may ignite in kilo sized quantities, but is handling kilo quantities of AP really something you want to try anytime soon?

I can say for a fact that it is unlikely to ignite the wax with small charges. I once set off a 10g AP charge (wrapped in thin plastic) underneath a plastic bag containing approx 300mL of petrol. It dispersed the petrol into a nice big cloud but didn't ignite it.

Admittedly the petrol and AP were seperated by about 0.5mm of plastic, and were not in direct contact, but then petrol ignites much more easily than wax.

[nbk2000]

Kilo quantities of AP are safe to transport if wet and then dried in situ at the test site.

Small amounts of AP aren't likely to ignite liquid gasoline, as the evaporative cooling of the dispersing fuel cloud will prevent it from reaching ignition temperature.

However, if it was already in a vaporous (and highly ignitable) state, then a little AP would likely go a long way. ;)