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Author: Subject: Methyl Ethyl Ketone Peroxide
chemoleo
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[*] posted on 4-4-2005 at 17:05


Interesting.
The unstable/sensitive nature of the mixed peroxide suggests to me that you have neither one of the species, i.e. it is NOT a mixture of AP/MEKP, instead it's a 'new' compound that has intermolecular crosslinking etc; a compound which is thermodynamically LESS stable than either of the respective high-stability species (AP/MEKP). High stability is relative here, of course.
Essentially it is a new compound, whose structure is likely to vary according to the ratios of AP and MEK.
I do wonder how mixed peroxides of acetylacetone (pentadione), others and MEK/acetone would behave. This result suggests there is potential for new compounds to be discovered! They may not be that different in physical properties (i.e. all are explosive, all rel. sensitive) but their structures are likely going to differ between different ratios and so on.

[Edited on 5-4-2005 by chemoleo]




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[*] posted on 4-4-2005 at 18:41


IMO ...

The 50/50 MEKP/AP liquid is not unstable ,
not overly sensitive , not thin but syrupy ,
not a distinct compound but a solution of
trimeric AP in dimeric MEKP , and best made by coprecipitation exactly the way it was described .
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[*] posted on 4-4-2005 at 18:52


What's the evidence for independent 'coprecipitation'? Somehow I cant believe that acetone and MEK would react seperately/independently (being extremely similar in nature - the difference being a single CH3 group), while not reacting with each other to form some crosslinked compounds of unknown overall composition.
Anyway. Did you try the 20:80 mix? I'd be surprised if fatkangoroo made it up just like that. Same holds for you i guess.
I haven't done this myself though, so I won't judge either way :)



[Edited on 5-4-2005 by chemoleo]




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Rosco Bodine
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[*] posted on 4-4-2005 at 19:08


There has been reference to mixed
organic peroxides and the behavior of
50/50 MEKP/AP is consistent with what
has been published .

I don't mean to start a flame war , but I
do doubt that chubbyroo even made the
stuff , and especially the part about the
dropped skewer .

Look , I have a half liter of the stuff which has been sitting quietly in storage , cool and dark , for nearly two years with no sign of decomposition .
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[*] posted on 4-4-2005 at 19:19


I followed the instructions, only difference being I used 50% peroxide and 30% hydrochloric.
To say I didnt do it and made the story up is a bit rude I think. I have better things to do.
The skewer story is very true.
I use the Aussie pink MEK so when the 2 are added I just a perfect pink mix. I stirred everything well. The whole reaction never went above 10.C.
The MEK was 100% the Acetone 100% peroxide 50% Hydrochloric 30% so thats pretty pure in my book. I have made normal AP many times. So its up to someone else to give a third opinion before we start calling names OK.
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[*] posted on 4-4-2005 at 19:36


Well the product I got was syrupy and very shiny , almost silvery in appearance ,
and it did not go bang when ignited but
did deflagrate with the characteristic orange fireball , even when a ml or two
was ignited . There was no undue sensitivity to the hammer test on a drop
soaked into a small ball of cotton , maybe
a bit more sensitive than straight MEKP .

So you are three for three in describing different properties for a product made from pink MEK , and using 50% H2O2 instead of 27% H2O2 .

It has to be be the mysterious pink component factor , no other answer :D

Try diluting your H2O2 to 30% with distilled water and then see what you get .

Maybe shake your pink MEK with some activated charcoal powder and filter it to
see if you can get the colorless form .

One more thing , the formation of the MEKP is initially more rapid than the AP , so at first the precipitate is richer in MEKP and thinner , but it gets more and more viscous with time of reaction as it becomes more and more loaded with dissolved AP which forms more slowly
as the reaction mixture stands .

How well does that square with "followed the instructions" ?

[Edited on 5-4-2005 by Rosco Bodine]
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[*] posted on 4-4-2005 at 21:57


Well I let the reaction go 20 hours. All the chems were put into frezzer before addition. First I let the MEK/Acetone mix together for 1 hour then slowly indroduced the peroxide making sure the temp didnt go over 10.C. Stirred that all up and let it sit for 1 hour. By this stage the mix was -5.C. Then the hydrochloric was added watching the temp at all times. Everything was given a good stir left to do its thing.
I always use 50% peroxide when making AP and HMTD and never had a problem. What has the % of peroxide got to do with it? Whats the colouring in the MEK got to do with anything? My stuff is red and about the same viscosity of motor oil. There is no need to tell storys when it comes to this stuff as its so piss easy and OTC that the truth will come out no matter what.
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[*] posted on 5-4-2005 at 06:25


Seriously , the dye is the only thing which I can think of which would account for the unusal sensitivity you are reporting .

Precooling the mixed ketones and peroxide separately before mixing and
then mixing them all together cold is good
procedure . And then if there is any significant warming , cool the mixture very cold again before beginning the initially
small additions of HCl . Your 50% peroxide is going to require slower initial
addition of the HCl because the initial exotherm is going to be increased compared to 27% peroxide . It is okay to
permit the initial reaction to rise to 25 C ,
and suspend additions of the HCl until the
initial exotherm subsides , then resume additions of HCl until all is added and let the mixture sit in the melting ice water bath . The precipitate of mixed AP/MEKP
should be viscous and syrupy when cold ,
although it is thinner at toom temperature , about like motor oil .

You can increase the amount of acetone relative to MEK in the original mixture ,
until you start getting undissolved crystals
of AP floating like little icebergs in the surface of the lower layer of mixed peroxides . Note the ratio of acetone to MEK which produces the effect and then you can reduce the amount of acetone in
subsequent syntheses until you get a liquid precipitate free of solids . The idea
is to get a solution of mixed AP/MEKP which doesn't crystallize out AP when cold . The ratios given by Mr. A are about right for the mixed peroxide product from
reaction using 27% peroxide . But you may be getting a slightly different composition of mixed peroxide from the reaction using 50% peroxide , and may need to adjust the acetone/MEK ratio to
obtain an identical product .

When you describe making multiple hammer strikes on the same wet spot of
mixed peroxide , getting a little bit to go off each time , that sounds about right .

Strange isn't it how that kind of impact wouldn't cause the entire wet spot to
go off , but the impact of a skewer wetted
with a little of the of the same wet stuff
would go off when simply dropped to the floor . I just have real difficulty reconciling the contradiction of what is
being represented there because it doesn't add up .
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[*] posted on 5-4-2005 at 12:49


I stand by everything I have said. The skewer was dropped just once, it probably would have gone bang again if I put a flame to it or hit it with a hammer. I didnt care about that, all I wanted to know is would it go off if I dropped it. I did the dropping skewer test 5 times and it went off 4/5 times. I dont why you would suggest I never even tried the experiment, its not like its very hard or expensive to perform. No special glass no heat. To easy.
Now its up to someone else to give a opinion.
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[*] posted on 5-4-2005 at 13:32


Quote:
Originally posted by fatkangaroo
The skewer was dropped just *once*, it probably would have gone bang again if I put a flame to it or hit it with a hammer. I didnt care about that, all I wanted to know is would it go off if I dropped it. I did the dropping skewer test 5 times and it went off 4/5 times.
Please clarify how you can do a test "just once" but also do the same test 4 or 5 times . Never mind , I understand now you mean one drop per test , in several repetitions resulted in explosions on the first drop . I just don't get that sort of silver fulminate sensitivity from the
genuine AP/MEKP sample material which I have . To get that sort of sensitivity you would have to have some different organic peroxide or other impurity in the composition you made .
Quote:
I dont why you would suggest I never even tried the experiment, its not like its very hard or expensive to perform. No special glass no heat. To easy.
The reason I would suggest such a suspicion is because I am a trained observer , and two problems arise in your decription of what you have observed . #1 , What you report having observed does not square in several respects with what I have observed consistently several times about a synthesis which was devised and reported originally by me . And #2 , you contradict yourself in what you report , perhaps without even realizing it that you
are making inconsistent statements .
Quote:

Now its up to someone else to give a opinion.

Well everyone is entitled to their opinion ,
only some folks don't make any distinction between opinion and observation. In a science forum it's good to make the distinction between what's done and what's thought about or theorized .
It's good to repeat an experiment to confirm results before making conclusions anyway .

Oh and BTW , I still don't believe any of it what you reported . But that's just the opinion of the person who invented the composition and has made it several different times .

Update : I just retested some of my original sample which was made over two years ago by the date on the bottle and it
appears and behaves exactly the same way as when originally made . A small ball of paper towel wetted with a drop explodes when tapped fairly hard with an ordinary claw hammer , a little more of a tap than would be used to position a 16 D nail , a lighter tap just splatters the material . A wetted skewer was Zero for Three drops from 6 feet onto either steel or concrete , but would crackle and pop feathering the end of the skewer when touched by a flame . Ten drops of the liquid soaked into a 8 mm ball of paper towel and ignited by flame only deflagrated with an orange flash .
A drop wetting steel directly would detonate numerous times from repeated
blows as the hammer was angled slightly to expose a fresh wetted spot to the next blow .

That dropped skewer test you reported is such an unlikely sensitivity anomaly , I'd really like to see the video .

[Edited on 5-4-2005 by Rosco Bodine]
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[*] posted on 5-4-2005 at 15:23


I will the first to admit I am no chemist. And I can admit you know I lot more that me on the subject. But the fact is I tried your mixed peroxides its was very sensitive. So what? I dont care if you believe me or not , time will tell.
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[*] posted on 5-4-2005 at 15:32


Maybe there is something strange about Australian MEK .

And the " so what " is that I carefully report accurate data from my experiments , and when that doesn't square with what happens when somebody else tries to repeat and confirm the results , then I want to know what is the reason .
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[*] posted on 5-4-2005 at 16:20


I'll just comment on the fact that fatkangaroo's MEK sounds quite different from mine, which is 99.9% pure from a local science company, mine is thinner then water...very clear liquid, very much like my acetone in fact, I can't tell the difference except that the MEK is REALLY strong smelling! So there you have it...his is thick and pink...theres gotta be some serious additives.



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chemoleo
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[*] posted on 5-4-2005 at 16:27


I agree that the skewer result is odd. Fatkangoroo could you please test your stuff another way, in terms of sensitivity? One that is more 'scientific'?
There may be factors you (fatkangoroo) are not aware of. Skewer, what is it, apiece of metal (like chicken skewers :D). Maybe the mix reacted with it, due to left over acid, sensitised it whatever.
I believe him though. He's not the Hideki Matsumoto type. He must have done something slightly differnet that he omitted to mention. Becasue he finds an anomaly doesn't mean he lies as a result.
Oh well. As usual, a third person doing it with australian MEK & using his conc. 50% H2O2 would be good.

Rosco, you mention references on the acetone/MEK co-peroxidation. Would you like to point some out? I am not convinced that the peroxidation occurs separately, to form MEKP and AP, but no intermolecular products of unknown composition.

Smell of MEK:
I just had a sniff at pure reagent grade MEK (2-butanone), and to me it smells exactly like acetone, with possibly a very very slight acid like touch. It is also very fluid, definitely less viscous than water, and physically no different from acetone. If someone set two containers in front of me, one containing acetone, the other MEK, I couldn't tell them apart.

[Edited on 6-4-2005 by chemoleo]




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[*] posted on 5-4-2005 at 16:51


IIRC there's a patent reference and I'll dig it up later . I think I've posted it before in another thread .

Anyway , before the coprecipitation method I actually did perform separate syntheses for the AP and MEKP and then
dissolve the AP in the MEKP with warming to produce the same product . But I found it rather pointless and inefficient
and the yields lower and wasted steps
of manipulation which was all eliminated
by simply coprecipitating the desired mixed peroxides . I experimented with
the ratio of acetone to MEK to produce
a solution of AP in MEKP that is almost but not quite saturated .

The bona fide genuine AP/MEKP is not unduly sensitive or I wouldn't have shared the information knowing someone would get hurt fooling with the stuff .
Anyway , I stand by the synthesis and the
reported properties , for what is a useful
but experimental composition . I suppose
I should be a bit troubled when along comes someone with dubious reports about "extreme sensitivity" for a composition where that has not been my experience . I want the facts stated plainly , and any anomalies accounted for ,
rather than for rumor or false report to prevent others from interest in a valid composition .
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[*] posted on 5-4-2005 at 17:03


Ah, so that's what it is about... don't worry we'll see to your reputation :D

Anyway, you raise an interesting point when you dissolved AP in MEK. Since AP reaches a saturation limit when dissolving it in MEKP, using a large excess of acetone vs MEK would produce a liquid with AP crystals appearing, or a liquid that'd crystallise upon standing, or a wet waterinsoluble solid.
Is this the case, that is the question? How does the appearance of AP crystals in MEKP (at a given ratio acetone/MEK) correlate with the solubility of separately prepared AP in MEKP? The values should be the same. Else some additional reacitons are going on.

I am looking foward to the references.




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[*] posted on 5-4-2005 at 17:13


The solubilities generally correlate regardless of the method . However
it is one hell of a lot easier to get the saturated solution by coprecipitation
and it is the only way to get a supersaturated solution , which is actually
a quasistable eutectic without resorting to
unsafe melting operations . And if you supercool the solution and seed it , a lot of AP will indeed crystallize out .

Try GB309118 for mixed peroxides by a similar mechanism and coprecipitation .

[Edited on 6-4-2005 by Rosco Bodine]
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[*] posted on 5-4-2005 at 18:12


The skewers are around 10 inches long and made from bamboo. They were dipped on the flat end and dropped on concrete.
The MEK goes by the name" Plumbers mate priming pink fluid. Written on the label; 1000ml/L Methy ethyl ketone. No additives of any kind shall be mixed with this priming fluid.Priming fluids shall be used to prepare the jointing surface prior to solvent cement application.
[img]http://www.imagebarrel.com/myimage.php?img=05/96/03/dav016jpg[/img]

[Edited on 7-4-2005 by fatkangaroo]
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[*] posted on 6-4-2005 at 21:20


Go here for some photos of my chems for anyone interested.
www.albumtown.com
name: freddy
Password 1234abc
The photos are pretty bad but you get the idea.
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[*] posted on 6-4-2005 at 22:43


I'm sure this is something most people know...however the primers that I use at work, usually have some THF along with is it "cyclo-something"? mixed in with the primer...could this be causing the differences?



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[*] posted on 7-4-2005 at 05:59


The extreme sensitivity is evidently due to
some adulterant in the " primer " which is
most definitely * NOT * pure MEK .

The product should be destroyed immediately because of the potential
for spontaneous decomposition / detonation .

Only pure precursors should be used for
the synthesis .

AP and MEKP are among the most stable of the organic peroxides when pure ,
but are very chemically reactive and can be destabilized / decomposed by contact
or mixture with some other substances .
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[*] posted on 7-4-2005 at 12:53


I dont think the MEK has anything to do with it. Earlier in the thread Axt tested regular MEKP made from "priming fluid"without any unusual sensitivities. Wouldnt any strange propertiess be carried over to the MEKP if the MEK itself was it fault? I dont find it strange that 2 peroxides mixed together will be more sensitive that a single peroxide on its own.
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[*] posted on 7-4-2005 at 16:37


Quote:
Originally posted by fatkangaroo
I dont think the MEK has anything to do with it. Earlier in the thread Axt tested regular MEKP made from "priming fluid"without any unusual sensitivities. Wouldnt any strange propertiess be carried over to the MEKP if the MEK itself was it fault? I dont find it strange that 2 peroxides mixed together will be more sensitive that a single peroxide on its own.


Axt also made some of the mixed peroxide , possibly using the same
" primer " instead of actual MEK , and
in an e-mail told me about it being suspected of spontaneously deflagrating and causing a brush fire . Now you can store a contaminated batch and await the potential fire and or explosion . But when it happens don't argue that it is due to the instability of a pure AP/MEKP composition , because that isn't what you are observing . For safety reasons you should not store that contaminated batch .
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[*] posted on 7-4-2005 at 17:20


I wouldn't be so quick to point at the MEK source, there are other chems involved especially the source of HCl which I guarantee isn't pure. Diggers HCl contains what I believe to be dissolved Fe salts which may have an undesirable catalytic effect on the peroxide product, or even in its formation.

I can't remember the HCl I used which resulted in the experiance as told above, but I was using clear primer, no dyes, marked 1000ml/L MEK, and it was AP added to MEKP, not coprecipitated. The MEK was a different brand to yours Fatkangaroo, though could of course be derived from the same source. Heres a couple types I have sitting around, there is another available here as well.

<center><img src="http://ww1.altlist.com/~58717/pulse.altlist.com/banners/mek.jpg"></center>

The fire was caused by 50% H2O2 falling onto dry grass as its bottle was puntured by <i>something</i> during the "explosion" which didn't even shatter the beaker in which it was contained. It was a very odd incident, for which I cannot give an explanation.
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[*] posted on 7-4-2005 at 17:21


I threw that useless shit away days ago. Kept 25ml for playing with. Well boo hoo for me. Guess I wont be making any.
Whoops didnt see your post Axt. Well different hydrochloric aye. Not a problem I know where to get another brand. I will give it another shot and see how I go. I have only attemped this twice so third time lucky;)

[Edited on 8-4-2005 by fatkangaroo]
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