Redgum whistle mix and degradation of WM due to copper compounds

[mabuse00]

The days are getting shorter again and I feel the itch for some new tests

 

Using RG in whistle was mentioned here in the forum, I'd like bring that up again.

 

https://www.youtube.com/watch?v=kX5X2oq71bM

 

Maybe Explosives Laboratory is even here in the forum?

 

Anyway:

Copper oxychloride will begin to degrade your whistle fuel after about a week. Give it a few months and the rocket or other devices made from it will likely explode. This is due to the Oxychloride chemically damaging the benzoate through unauthorized bondage to random positions on the benzoate creating cyclopentadienyl ligands that make the fuel to hot, causing your motor to detonate. However, note that it is possible to counteract this issue to a certain extent by adding an additional 0.5% Ferrocene or Vinylferrocene to your whistle mix, when using any catalysts containing Cu.

Can somebody comment on this, is there some source?

I have some samples leftover from 2020, can assume these to have a measurable increase in burnrate? And concerning using RG, my idea of the process would be like EL describes it in his comments, like I would with RG bound BP. What is your preferred process? I could also imagine using plain water and dissolve the benzoate rather than the RG...?

 

Another thought: will RG have an influence on sound production? I could imagine it to smoothen the burn, stepping in between the pulses, like it would in a barium nitrate based strobe. I know that adding charcoal or BP will do this.

Not that it's a problem if the objective is a powerful lifter, I'm just curious. Judging from Explosives Laboratory's video it still screams, but - maybe less than without?

 

 

PS:

Concerning water vs. alcohol granulation - I'm not sure, but I think I remember some star experiments from a long time ago - once dissolved by alcohol, the RG stayed sticky... I think permanently...

Edited October 15, 2022 by mabuse00

[cmjlab]

I am not in a position to answer with any certainty, but I have several batches of whistle mix made with Copper Oxychloride from various times over the past few years. None of them sound / appear to have deteriorated or detonate, regardless of being loose in the container or pressed in a tube. Some of the whistle is used as a burst booster in shells, and has no phlegmitizer included.

 

As for Red gum, I also tried that recently, it was the "new Whistle" on FW.com (uses red gum and perlite)from Neighbor J I think, and if anything the mix burned much quieter than normal K Benz whistle, with a borderline dog whistle sound to it. They were small tubes (5/16" spollette), but it made me not want to try any further with it. I use normal K Benz and it's much louder in the same size tube. I can't speak to it's lifting power though, I don't make enough rockets to have enough experience to compare.

 

Charles

[mabuse00]

I have some samples leftover from 2020, can assume these to have a measurable increase in burnrate?

The burnrate of the old stuff just proved to be identical - at atmospheric pressure that is.

[DecimusMaximus]

What is the purpose of fulvic acid for this formulation? Fulvic acid is mainly trace minerals for humans and plants i cant imagine what a whistle fuel would need that for. 

Edited June 21 by DecimusMaximus

[DavidF]

mabuse00 previously mentioned this quote from Explosives Laboratory on YouTube:

"Copper oxychloride will begin to degrade your whistle fuel after about a week. Give it a few months and the rocket or other devices made from it will likely explode. This is due to the Oxychloride chemically damaging the benzoate through unauthorized bondage to random positions on the benzoate creating cyclopentadienyl ligands that make the fuel to hot, causing your motor to detonate. However, note that it is possible to counteract this issue to a certain extent by adding an additional 0.5% Ferrocene or Vinylferrocene to your whistle mix, when using any catalysts containing Cu."

I wonder what Mumbles might say about this? This is the only time I've ever seen copper oxychloride described this way.

mabuse00, Explosives Laboratory is the same guy as  ShortFuseMan on YouTube. You can tell by the voices. Maybe that channel will have more info for you.

I'm also curious what Mumbles might think about his use of methyl salicylate (oil of wintergreen) as a fuel/phlegmatizer/consolidation aid for salicylate-based whistle propellants. Any potential issues come to mind?

[DecimusMaximus]

10 hours ago, DavidF said:

mabuse00 previously mentioned this quote from Explosives Laboratory on YouTube:

"Copper oxychloride will begin to degrade your whistle fuel after about a week. Give it a few months and the rocket or other devices made from it will likely explode. This is due to the Oxychloride chemically damaging the benzoate through unauthorized bondage to random positions on the benzoate creating cyclopentadienyl ligands that make the fuel to hot, causing your motor to detonate. However, note that it is possible to counteract this issue to a certain extent by adding an additional 0.5% Ferrocene or Vinylferrocene to your whistle mix, when using any catalysts containing Cu."

I wonder what Mumbles might say about this? This is the only time I've ever seen copper oxychloride described this way.

mabuse00, Explosives Laboratory is the same guy as  ShortFuseMan on YouTube. You can tell by the voices. Maybe that channel will have more info for you.

I'm also curious what Mumbles might think about his use of methyl salicylate (oil of wintergreen) as a fuel/phlegmatizer/consolidation aid for salicylate-based whistle propellants. Any potential issues come to mind?

I made the Whistle of Wintergreen today( great name btw) and it was fast! Bonus: it was fun to make because the methyl salicylate (oil of wintergreen) smells great. From my understanding of it, the methyl salicylate as a fuel/phlegmatizer/consolidation  makes sense since the salicylate will make it bind much better to the sodium salicylate due to being closer in molecular structures. (im no chemist but this is my understanding of it). Since it is an oil, just like mineral oil, it will act as a phlegmatizer too so that makes sense as well. Because the methyl salicylate and the sodium salicylate  are similar, it doesnt try to break its bonds or expand away so it shouldnt crack or shift too much in the fuel grain. (also another guess of mine based on what I've read and understand)
I will be pressing a rocket with it soon!

Back to the my original post, fulvic acid definitely seems to help the whistle mix based on some AI research I did but I wish more would chime in who knows this stuff. 

 

and yes Explosive Lab and ShortFuseMan do sound like the same people/group. 

[Mumbles]

I will start by saying that I have heard a few people mention that certain whistle mixes tend to "go bad" faster than others.  I've heard copper catalyzed as one mentioned as being more susceptible to this.  I don't know how much truth there is to this vs. just someone less experienced having issues unrelated to the catalyst (moisture, tube relaxation, cracking, poor pressing, etc).  Copper oxychloride is one of the stronger catalysts for whistle, so it would make sense that some issues may become more apparent much faster as there is less window for proper flight vs. CATO.

Now, his explanation for this is total bullshit.  As an actual chemist who actually regularly works with cyclopentadienyl compounds I can pretty confidently say there is absolutely zero merit to this or even a feasible way to make them from benzoates or salicylates.  IF, and that is an extremely big if, there is any sort of chemical reaction or decomposition happening, it would make benzene/phenol or coupled products.  

As for the ferrocene or vinyl ferrocene, I can't speak much to that.  If there's any merit to it, they might be acting as antioxidants or coupling partners to what I mentioned previously.  On a more interesting note though, ferrocene and vinylferrocene are noted to be pretty good catalysts themselves in high powered rocketry.  I've always wanted to send some out to someone with a rocket test stand for testing in whistle mixes, but don't have a good source for it anymore.  Anything interesting in this regard I have access to isn't very air stable.  

Methyl salicylate is an interesting choice for the solvent for whistle mix.  I'd bet it at least partially dissolves the benzoate or salicylate.  I don't know if I'd call it a real phlegmatizer, as it will eventually evaporate.  Let us know how it works out in rockets.  I'm definitely intrigued. 

[DecimusMaximus]

15 hours ago, Mumbles said:

I will start by saying that I have heard a few people mention that certain whistle mixes tend to "go bad" faster than others.  I've heard copper catalyzed as one mentioned as being more susceptible to this.  I don't know how much truth there is to this vs. just someone less experienced having issues unrelated to the catalyst (moisture, tube relaxation, cracking, poor pressing, etc).  Copper oxychloride is one of the stronger catalysts for whistle, so it would make sense that some issues may become more apparent much faster as there is less window for proper flight vs. CATO.

Now, his explanation for this is total bullshit.  As an actual chemist who actually regularly works with cyclopentadienyl compounds I can pretty confidently say there is absolutely zero merit to this or even a feasible way to make them from benzoates or salicylates.  IF, and that is an extremely big if, there is any sort of chemical reaction or decomposition happening, it would make benzene/phenol or coupled products.  

As for the ferrocene or vinyl ferrocene, I can't speak much to that.  If there's any merit to it, they might be acting as antioxidants or coupling partners to what I mentioned previously.  On a more interesting note though, ferrocene and vinylferrocene are noted to be pretty good catalysts themselves in high powered rocketry.  I've always wanted to send some out to someone with a rocket test stand for testing in whistle mixes, but don't have a good source for it anymore.  Anything interesting in this regard I have access to isn't very air stable.  

Methyl salicylate is an interesting choice for the solvent for whistle mix.  I'd bet it at least partially dissolves the benzoate or salicylate.  I don't know if I'd call it a real phlegmatizer, as it will eventually evaporate.  Let us know how it works out in rockets.  I'm definitely intrigued. 

The methyl salicylate works great in rockets!! This is the fastest I have ever seen my strobe rockets go up. It was so fast and smooth, I could barely hear the rocket go up lol (not sure if I like that wish there was more whistle but its impressive nonetheless). This was only about 1.5" of whistle fuel on the spindle out of a total 3.2" spindle that I home made. It was carrying about 18 grams of flash with a total header weight of about 55-70 grams (glue, casing, paper and fuse).

 

Edited June 27 by DecimusMaximus

[DavidF]

This has been an interesting discussion! Thanks to Mumbles for the chemist's opinion. Here is a statement made by the originator of the WoW propellant, from his comment section on the Whistle of Wintergreen video. Hopefully my copy and paste of it will clarify why I asked what Mumbles thinks earlier. 

"

@ShortFuseMan

3 months ago

Methyl salicylate in this composition acts as a unique type of plegmatizer that forges with the sodium salicylate ❲or whatever other fuel you may choose to use❳, splicing into it on a very close molecular level, and is able to contribute additional audio and power to the whistle propellant mixture, which is not typical of the usual plegmatizing agents usually used in these particular contextual scenarios to stabilize whistle mixes. Methyl salicylate, therefore, is an extremely exceptional plegmatizer for these purposes, as the oxidizer ❲in this case, just potassium perchlorate❳ treats it very similarly to the main whistle fuel when it comes to combusting it. This is because of the molecular structure of methyl salicylate, as said already. It is an aromatic compound based on the benzene ring, just like all the whistle fuels, meaning it has highly similar combustion characteristics to the main whistle fuels, i.e. whistling loudly when burned in the presence of a strong oxidizing agent and especially so when also in close proximity to a catalyzing additive. The only difference between the main whistle fuels and compounds like methyl sali is the fact that it is a low molecular-weight organic ester as opposed to an ionic salt, making it an oily liquid at standard temperatures and pressures. Alternatively, methyl/ethyl/propyl/butyl benzoate or methyl/ethyl/propyl/butyl phthalate all can also be used as viable alternatives or replacements. Diethylmethylbenzamide, benzyl benzoate, benzyl alcohol or its esters, methyl anthranilate, acetophenone, benzaldehyde, or anisole are all additional examples of similarly employable compounds with parallel compatability. If you would possibly want to step things up to the top notch and get extra outgoing, using aniline or nitrobenzene would be the protocol for ultra-extreme performance, yielding superbly impressive ISP in the final propellant, due to the significantly catalytic nature of aromatic amino and nitro groups in energetic situations."

 

______________________________________________________________________________________________________________________________________________

 

There are other claims made in the same comment section, which indicate that that there must have been a LOT of testing done to arrive at all the conclusions put forward, but no mention of test results is made. One other thing I've never heard of is the use of isatoic anhydride as a preservative for long storage. I'd be grateful to see Mumbles give the video and comments a looksee and let us know what he thinks about the veracity and safety of the information and process.

 

Whistle test results I've seen in Pyrotechnica editions show that the 'ideal' F/O ratio for benzoate whistle propellants is higher than with salicylate propellants. The typical salicylate formula most pyros use (especially for strobe rockets) is 

76- potassium perchlorate

23- sodium salicylate

  1- red iron oxide

 3- Vaseline, dissolved in solvent. (I use 2.5 paraffin wax, dissolved in naphtha).

 

I wonder how compatible/miscible the methyl salicylate is with different solvents, if that is used instead of the 'usual' phlegmatizers. The way I understand phlegmatizers is that they reduce friction and desensitize whistle to reduce danger when pressing. Vaseline stays in the propellant, other than what may soak into the tube. Wax stays in and on the propellant. Recently, the use of paraffin lamp oil has been suggested as a phlegmatizer that gives great performance. I don't know how relevant this is, but I have observed that the lamp oil evaporates completely when it's out in the open. Does it 'disappear' in a whistle rocket motor? I don't know. If it does disappear, does that affect the likelihood of a CATO? I don't know. As Mumbles suggested, methyl salicylate may also evaporate. People have various opinions on why whistle rockets CATO on storage, but I think everyone can agree that the key factor is CHANGE. To that end, we'd want to make motors that are resistant to change. I think the main reason for change is because the phlegmatizers affect the ability to form a physically stable propellant grain. They are lubricants, not binders. This is just my speculation.

 

The salicylate whistle propellant is for use with shorter spindles and will yield MUCH more thrust than a typical benzoate whistle formula like say 70-30-1-3 when used on the same spindle. It's referred to as SLD #2 whistle (Steve LaDuke). My GUESS is that SLD#2 whistle would outperform WoW propellant because of the F/O ratio. This means you'd use less of it, leaving more room for strobe, which would give louder pops.

 

DecimusMaximus, that was a nice rocket. I'm not a chemist and I don't play one on TV, but I would just wonder about the safety of taking an experimental whistle propellant and using it in a strobe rocket. There could be sensitivities nobody knows about? I'm not trying to be a party pooper here, but I'd hate to see an accident happen because nobody questioned new information. I hope my abundance of caution is taken as intended, and not as a dig of any kind.

 

 

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[Mumbles]

All I really meant was that his explanation that copper catalysts cause benzoates/salicylates to decompose into cyclopentadienes, which then "over catalyze" the whistle doesn't really have any basis in how chemistry works.  Even if it did happen the potential metal cyclopentadienides are all air and moisture sensitive.  The rest I find very interesting.  

I didn't mean to cause a stir by suggesting that methyl salicylate isn't a true phlegmatizer.  I believe it may have gotten misconstrued due to some semantics of what I consider a phlegmatizer to be.  In essence, it's a material added to an explosive that reduce it's explosive tendencies and often improves the handling properties.  It probably has those properties while it's present.  All I meant is that because it has some volatility, it would eventually evaporate and lose the benefits.  To me, true phlegmatizers stick around more or less indefinitely.  Temporary phlegmatizer maybe is a better term for what I'd envision it as. 

Edit: It's less volatile than I initially thought, so I was probably wrong here.  I was confusing it's low odor threshold as having a higher vapor pressure than it actually has.  

[DecimusMaximus]

I was not worried about using methyl salicylate as a new ingredient/phlegmatizer because:

1. Its oil based. my understanding of oils and whistle comp is that it makes it have less friction because oil is not prone to be friction sensitive.

2. methyl isnt incompatible with any of the other ingredients.

3. shortfuseman launched an over 1000 gram header with it with no issues. 
 

4. i left the oil out and it did not evaporate or barley did. it had been 3 days and i could still smell it.

[DavidF]

OK, since there are no incompatibilities between methyl salicylate and strobe mix, I guess It's all good  My only concern was using a new experimental whistle mix in strobe rockets. Sorry. When we get older, we worry more.

[Richtee]

7 hours ago, DavidF said:

OK, since there are no incompatibilities between methyl salicylate and strobe mix, I guess It's all good  My only concern was using a new experimental whistle mix in strobe rockets. Sorry. When we get older, we worry more.

In this arena, that’s HOW we get older 😗

[DecimusMaximus]

On 6/29/2024 at 6:06 PM, Richtee said:

In this arena, that’s HOW we get older 😗

Hah funny!

Heres another whistle of wintergreen strobe rocket that I pressed.
Made with the spindle that I machined on the left. The right is a new spindle I just built on the lathe for a stronger lift and louder strobe pops.