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

Printable Version  
 Pages:  1    3  4
Author: Subject: Mr. Anonymous: azo-clathrate primaries
Polverone
Now celebrating 21 years of madness
*********




Posts: 3186
Registered: 19-5-2002
Location: The Sunny Pacific Northwest
Member Is Offline

Mood: Waiting for spring

[*] posted on 7-3-2003 at 13:37
Mr. Anonymous: azo-clathrate primaries


Quote:
From: Anonymous
To: (my e-mail address)
Subject: azo-clathrate synthesis

Please allow me to share a good link for some printable basic tables and charts which are useful. http://chemdat.merck.de/cdrl/services/labtools/en/tools_body...

The tables for aqueous solutions of common acids and bases are very good for handy reference.

Near the end of my third message posted here, I made brief mention regarding a patent about a class of energetic materials, which are complexes called clathrates. Experiments with that class of compounds have produced very positive results. I wish to share the results of my experiments and other information to emphasize and explain the importance and usefulness of the outstanding basic lead picrate complexes of US3431156. The compounds described by the patent are truly exceptional energetic materials, quite unlike the ordinary picrate salts which are poor initiators by comparison. The azo-clathrates are small critical mass unequivocal primaries which demonstrate very high brisance. For example, a small test pellet of the material (formed by making a stiff putty of a small amount of the dry material wet with a minimum amount of saturated aqueous dextrine solution and allowing small droplets of the paste to dry upon a plastic film) shows the power of the composition. A small droplet of the dried, dextrine bindered material weighing 35 milligrams, will produce a clear aperture, clean edged hole when placed upon a thin aluminum witness plate and detonated by touching with a glowing splint. The metal is not merely punctured nor is there any deep dent nor any significant "banana peeling" effect for the metal on the underside of the witness plate. The metal adjacent even such a small charge is simply granulated and blown away, atomized to dust in its disintegration. The effect is much the same as if a hollow drive punch like is used for sheet metal work had been placed upon the witness plate and struck by a hammer. This sort of cutting effect upon metal is demonstrated only by high velocity explosives. It is especially unusual and interesting when the effect is observed for such very small charges. Miniature shaped charges are a reality.

There simply are no comparable materials to my knowledge anyway, which can be readily made from OTC raw materials. And there are only a very few of the most exotic and much more difficult to make materials discovered which are comparable or marginally superior as substitutes for these more easily and cheaply made materials. If you have been looking for the "good stuff", delving through the literature and experimenting away, do yourself a favor and dont try to reinvent the wheel, while failing to directly evaluate these much more simple, economical materials and witness their excellent performance firsthand.

I have made these compounds several times from precursors every one of which was also made from OTC materials. The synthesis of the sodium azide is the most difficult part, but worth the trouble if no convenient source for sodium azide is available. Going on record as a purchaser of sodium azide could be unwise, so I have chosen to avoid that potential worry. Since the sodium azide is the most difficult precursor the effort was made to develop the most efficient use for the sodium azide, in producing the highest quantity possible of a satisfactory initiator.

After referring to my lab notes, I saw that it was actually a slight variation of example compound 5 of the patent US3431156 which I synthesized, and my variation had produced a quantitative yield, which is a marked improvement over the 82 per cent yield reported by the patent. The patent had reported (line 10 page 6) that up to 13 moles of lead azide were possible to be absorbed by each 4 moles of the host complex, but that an upper limit of 11 moles would be used for production to reduce the potential precipitation of lead azide which may not be trapped in the matrix of the host complex. By a modified reaction sequence and higher temperatures, I achieved good results increasing to 12 moles the entrapped azide for each 4 moles the host compound of example 5, and achieved a quantitative yield of end product, agreeing with the increased molecular weight for the added 1 mole of lead azide. The molecular weight for the clathrate compound of example 5 is 9311.85, while the variation I made has a molecular weight of 9603.08. When it comes to molecular weights, all of the clathrates are astonishing, as is their ease of synthesis, storage stability, chemical stability, and initiatory power. The azo-clathrates have "the right stuff". The compounds retain the desirable initiating quality of lead azide, while eliminating its faults.

My theory is that the way in which the host complex is made and the conditions under which the azide is subsequently added to the host complex has a bearing upon increasing the upper limit of how many moles of entrapped lead azide it may contain, and the saturation limit can vary also according to the particular host compound, 16 moles of included lead azide may be possible from indications in some of my experiments with host compounds mentioned but not specifically detailed in the patent US3431156 as experimental examples. This is what I meant by saying that "A similar process can be used to provide enrichment to the properties of the compound in example 4 of US3293091."

To my thinking the patent US3431156 is a "goldmine" of data as a technical disclosure itself, as well as suggesting further general experiments or refinements related to the example compounds it discloses. It really surprises me there are no subsequent patents having been published since 1969 regarding further work on the same general type of compounds. Perhaps Remington Arms and DuPont have done further experiments but kept the research confidential for business reasons. There was an earlier mention of the formation of complexes of this sort in a 1922 patent GB180605, by the German chemist Dr. Walter Friedrich, (see line 98 page two), however there were no detailed examples. It seems likely that some of the early references to "mixed salts" may have in fact been clathrates, but many years would pass before the details would be described extensively for the first time as an advanced art in US3431156.

Described below are the synthesis details for my experiment with a slightly enhanced variation of the general type of compound described in US3431156, example 5. It is interesting when when a synthesis produces quantitative yields, for several reasons. It is a rare result, and many times the stability of a product from a quantitative yield synthesis is excellent. The resulting product has formed from a synergy of reactions which went to completion without side reactions and byproducts, and efficiently formed the target compound as the single "most probable" result, excluding other possible products. The intended product of a high yield synthesis will often prove to be very stable and high purity compound. The inherent quality control involved is desirable for materials to be used as explosives. A synthesis of 4 (basic lead picrate, lead nitrate, lead azide) 12 (lead azide) molecular weight 9603.08

NOTE: In my opinion the proportional formula designation for clathrates is somewhat arbitrary, but the ratios are correct. For example the theoretical minimum molecular weight might be only one fourth of 9603.08, or the actual molecular weight could be any one of several multiples of that number. Its a damn mystery, so I shall leave the true structural determination to others who have the instruments required and the interest to pursue such questions. Crystallographers are sure to enjoy pondering the actual structure of this energetic "Buckyball" sort of molecular matrix.

Experimental :

An alkaline solution of sodium picrate is made as follows:

4.6 grams (four and six tenths gram) pure dry pale yellow picric acid is dissolved with stirring in 180 ml hot distilled water, and to the stirred solution is added a solution of 1.7 grams (one and seven tenths grams) NaOH in 40 ml distilled water. The sodium picrate solution is transferred to an addition funnel and kept warm in a hot water bath.

Into a tall form (Berzelius) 500 ml beaker is placed a magnetic stirbar and 100 ml of distilled water. On a stirrer hotplate is made a hot solution of lead nitrate by adding 25 grams (twenty-five grams) lead nitrate to this stirred 100 ml of hot water. While stirring, this lead nitrate solution is heated to and maintained just below the boiling point. 95 degrees centigrade is fine.

The warm sodium picrate solution is added dropwise slowly at a rate of about one drop every two or three seconds, into the vortex of the vigorously stirred hot lead nitrate solution, continuing stirring and heating for ten minutes after the addition is completed. The precipitated material will initially be bright yellow, and change slowly in color to a darker orange, as a more mature crystalline precipitate is developed towards the end of this step in the synthesis, which results in a suspension of crystalline basic lead picrate, possibly basic lead picrate / lead nitrate double salt, in residual lead nitrate solution.

The valve on the addition funnel is closed, and in the addition funnel is placed a solution of 5.3 grams (five and three tenths grams) of sodium azide dissolved in 50 ml of distilled water. This sodium azide solution is added very slowly by drops, at a rate of about one drop every four or five seconds, to the vigorously stirred suspension of crystals. These basic lead picrate crystals suspended in the stirred mixture with remaining lead nitrate will be changed in color and size as they react with the sodium azide being introduced. This change is due to the formation of the host complex and its subsequent saturation with entrapped lead azide formed within the "cage-crystal matrix" of the host complex. Heating and stirring is continued past the end of this sodium azide addition, for an additonal ten minutes and the heating is then discontinued, yet vigorous stirring of the slowly cooling suspension of microcrystals is continued, maintaining the crystals in suspension for an additional 1 hour as the beaker and its stirred contents slowly air cools. These slow additions and extended periods of stirring are necessary for good completion of the reactions and good crystal formation. The clathrate complex has a very low solubility and so its crystal development is a bit sluggish, and requires the very gradual, steadily maintained and controlled reaction conditions be followed as described for best results.

The stirring is stopped and the reaction mixture is allowed to cool to room temperature. The supernatant liquid is decanted from the crystals, and the crystals are rinsed with 50 ml of distilled water, and washed from the beaker onto a coffee filter with a stream of distilled water from a wash bottle. The filter is placed upon a stack of paper towels to blotter away most of the residual moisture. The granulation mesh of the microcrystals is extremely fine, and there is a point at which the drying crystals are not quite completely dry, when the material may be freed of lumps by light pressure applied by a plastic spoon. The yield of dried crystals is 24 grams, which is 100 per cent of theory.

Try obtaining a 24 gram yield of a first class primary any other way from only 5.3 grams of sodium azide, and the economy of this compound is soon realized.
View user's profile Visit user's homepage View All Posts By User
Polverone
Now celebrating 21 years of madness
*********




Posts: 3186
Registered: 19-5-2002
Location: The Sunny Pacific Northwest
Member Is Offline

Mood: Waiting for spring

[*] posted on 7-3-2003 at 13:39


Mr. Anonymous, whoever you may be, thank you for the continuation of your detailed and valuable reports. I realize that it must take some time to prepare these messages, but please continue to share them as long as you have things to say and time to say them.
View user's profile Visit user's homepage View All Posts By User
Madog
Hazard to Others
***




Posts: 221
Registered: 20-5-2002
Location: USA
Member Is Offline

Mood: lysergic

[*] posted on 7-3-2003 at 18:06


mr annonamous, I LOVE YOU!!!



Most people outgrow their pyro tendencies, we are the ones who\'s tendencies outgrew us.
View user's profile Visit user's homepage View All Posts By User This user has MSN Messenger
bigbob
Harmless
*




Posts: 4
Registered: 6-3-2003
Member Is Offline

Mood: recrystallizing

[*] posted on 8-3-2003 at 12:37
Hard Numbers


I'd like to know if anybody has been able to find some hard numbers on this compound (complex?)? I so far have not been able to. I was thinking along the lines of vdet, trazul tests, drop tests, flame sensitivity, etc...this seems to be a very interesting compound which on top of that is relatively easy to synthesize. Keep up the good work!

[Edited on 8-3-2003 by bigbob]




If everybody carried a gun, it\'d be a much more courteous world.
View user's profile View All Posts By User
Polverone
Now celebrating 21 years of madness
*********




Posts: 3186
Registered: 19-5-2002
Location: The Sunny Pacific Northwest
Member Is Offline

Mood: Waiting for spring

[*] posted on 8-3-2003 at 13:20
ode to an initiator


Normally I'd put something like this in Whimsy, but I doubt that Mr. Anonymous would be able to see it there.
Quote:
From: Anonymous
To: (my e-mail address)
Subject: ode to an initiator -

My pretty million crystals glitter in the sun,
prisms from the mixture that formed them every one.

In the cauldron mother liquor, a bit of this and that,
the cradle of creation for crystals there appear.

What will be your spectral gifts of ever changing hue,
little diamonds in the magic broth now shimmering so new.

My pretty azo-clathrates you have your act down pat,
to weather many storage trials, so stable and serene,
so mellow and mild mannered your values quietly seen,
till one day the kindling spark,
the marching call has come,
and fully suited to your task, high order just like that.
The synergy of partners, oh the beauty of the dance!

Your molecular enormity, high density, and high energy is a must,
small critical mass primary unequivocality, well disciplined but true,
the aluminum witness plate is all ways so overmatched by you,
as if punctured by a laser, the clean edged signature hole of metal wrent to dust.

Berzelius beakered pedigree or lowly mason jar,
you never minded or complained, knowing your full worth.
Gleam there in the sunbeam spotlight on your filter cake.
Little microcrystals, shine on there awhile,
shine on like the stars you are for when your work has come,
for there you have your job to do, as masters of the art.
View user's profile Visit user's homepage View All Posts By User
Polverone
Now celebrating 21 years of madness
*********




Posts: 3186
Registered: 19-5-2002
Location: The Sunny Pacific Northwest
Member Is Offline

Mood: Waiting for spring

[*] posted on 9-3-2003 at 12:22


Quote:
From: Anonymous
To: (my e-mail address)
Subject: hard numbers for azo-clathrates

Comprehensive test data for the 4/12 azo-clathrate and other "designer explosive" variations is unavailable so far as I know. Many "designer compositions" are possible for these type complexes, but some representative general examples are described by the patent. The velocity would of course vary with diameter of the charge and confinement. Exactly what is the velocity, I dont know, but the witness plate evidence is that the number will be high. I do know the material is capable of high order detonating sensitive secondaries even in small diameters with no confinement whatsoever. I did not test PETN, but the indication is that the amount of initiator required would be small, and even close proximity to the PETN would likely set it off.

To get a general idea of some figures which would describe initiator quality, see the general performance table beginning line 29, page 3 of US3431156 for related, but slightly less powerful compounds. The figures would be as good for the 4/12 complex because of the increased relative content of lead azide in its total weight. The lead azide content is the homogeneous internal accelerator of the "booster matrix" of the host compound. Note that the initiator charge weights on the table are in grains, not grams. One grain is about 65 milligrams, so the charges are small, the quarter grain charges are a little over 16 milligrams. Also note that the test capsules are miniature detonators about three quarters of an inch long.

To fully initiate a two gram secondary in a magnum sized cap for insensitive blasting explosives, would require very much larger initiating charges to "overdrive" the secondary, as is desirable for good cap performance. In practical sized detonators, the azo-clathrate would perform on a weight basis only, slightly less good than pure lead azide would perform. However, it is good to keep in mind that pure lead azide is used only freshly prepared as a lab test standard, and not used otherwise because of its dangers for field use. And on the weight basis of lead azide entrapped within the azo-clathrate, there is less azide present in a comparable charge of the azo-clathrate, than for a charge of pure lead azide having equal power, so the net effect is that the power of the lead azide itself is enhanced overall with respect to the amount of it required to participate in the initiation of the secondary. The efficiency of the lead azide entrapped within the host complex is increased in comparison to the lead azide used alone, on a weight basis for the lead azide component only. So, the host complex does not function as a diluent for the lead azide, but amplifies the effect of the lead azide. The energy of the host complex alone and the practical value of the lead azide alone are each inferior to the sum obtained when the two are combined in the same crystalline structure, where the properties of each complement the other. A similar synergistic phenomena has been observed for simple physical mixtures of lead azide with other materials, like lead styphnate, (for example 1 part lead azide to 2 parts lead styphnate) where the mixture has greater initiating power than may be accounted for by the performance of either constituent alone. Coprecipitated lead azide, lead styphnate "surface bonded crystal" compositions have been produced. However in those compositions the exposed lead azide is still subject to deterioration and static sensitivity, and chemical instability that are problems which the azo-clathrates have resolved. The general trend for the azo-clathrates is that all variations are exceptional initiators having desirable properties.

The difference that I have observed among them is that the small critical mass minimum required for unconfined high order detonation, varies with the lead azide content. The greater is the entrapped percentage of lead azide for a particular complex, the smaller becomes the size of a test sample which will high order detonate unconfined. The self acceleration and output can be varied to obtain a hotter or milder composition, by changing the precursors and their proportions to obtain whatever composition is desired for the end product, within the limits possible for a defined clathrate variety related to those precursors. At least dozens of different clathrate complexes are possible, each being a unique composition of matter having a definite formula.
View user's profile Visit user's homepage View All Posts By User
PHILOU Zrealone
International Hazard
*****




Posts: 2893
Registered: 20-5-2002
Location: Brussel
Member Is Offline

Mood: Bis-diazo-dinitro-hydroquinonic

thumbup.gif posted on 23-3-2003 at 17:06


This coprecipitating complex should contain:

6,63g Pb(OC6H2(NO2)3)2
11,64g Pb(N3)2
8,59g Pb(NO3)2

Total = 26,86 g

I wonder if mixing ultrafine powders of the above in the same proportion will lead to similar properties!
It is obvious each ingredient gives its bennefits to the others!
Pb(N3)2 sensitive HE free lots of N2
Pb(picrate)2 sensitive HE free lots of gases included a lot of unburned C!
Pb(NO3)2 oxydiser upon heating free NOx improve OB and heat output!




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
halfpindc3h6n6o6
Harmless
*




Posts: 1
Registered: 1-6-2010
Member Is Offline

Mood: No Mood

[*] posted on 1-6-2010 at 13:24


Bigbob heres "some" numbers, if you were asking for numbers regarding lead azide and lead picrate....
Pb Azide....
Det Vel=4600m/s
Lead Block Test=112cc
Deflag Temp=320*C
Impact Sens=High-4 Nm (scale 0 to 20 twenty being low)
Friction Sens=Very High-0.1 kp (scale 0 to 10 ten being low)
Water Sens=Low
Chem Formula=Pb(N3)2
Colorless crystals, initiate with hot spark, reacts violently with copper, brass, bronze, lead

Pb Picrate...
No specific numbers but commented as weak, suggests using booster.
Impact and friction very high 0.1
water sens. moderate
deflagrates 330C
Yellow Needle structure
Pb(C6H2N3O7)2.H2O

Source: Field Manufactured Explosives




[Edited on 1-6-2010 by halfpindc3h6n6o6]
View user's profile View All Posts By User
quicksilver
International Hazard
*****




Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline

Mood: ~-=SWINGS=-~

[*] posted on 2-6-2010 at 06:06


There is a difference between basic & normal lead picrate & in fact lead picrate may be synthesized to act in a moderately powerful manner. But the clathrate lattice is such that the efficiency of lead azide is maintained, yet it's static sensitivity may be lessened. This is an empirical observation - yet it makes sense due to lead azide's fault in this respect is supplanted by dextrinating; there seems every reason that developing a lattice crystalline would act in a similar fashion.
The clathrate is stable. Most everyone who has experimented with it - knows just how stable it is. It also is quite efficient; being slightly below service azide, LA1331, etc. It had long been my interest to determine what the elements of electric stimulation had on energetic materials (past posts). The limited research in that area placed lead picrate in a much lower sensitivity level than Azide, making the possibility of the clathrate safer, a possibility.
Additionally, the unique issue is that the proposed material had not seen it's way into multiple patents; making it's likelihood of trade secret another possibility




View user's profile View All Posts By User
Bert
Super Administrator
*********




Posts: 2821
Registered: 12-3-2004
Member Is Offline

Mood: " I think we are all going to die. I think that love is an illusion. We are flawed, my darling".

[*] posted on 22-1-2011 at 13:30


I had experimented with the "Mr. Anonymous" Lead azo-clathrate procedure perhaps 7 years ago. Unfortunately, the notes and resulting dialogue were posted on roguesci.org and I've gone through a couple of computer losses since- No lab notes left!

I had reason to revisit this lately, and am wondering if anyone has a more complete lab procedure. Most particularly the volumes maintained and total times required for those long, slow solution drips into the nearly boiling and rapidly stirred crystal suspension... I recall failure resulting from too fast additions, and 7 years down the road can't recall where the volume of the beaker was at on the successful attempts. I do recall significant water being needed to wash down the solids on the beaker wall and make up for evaporation.

So disappointing to spend 4 hours at the bench only to see voluminous, ugly, mustard yellow mud instead of those nice, dense, sparkly micro crystals...

As Austin Powers said: "I've lost me mojo!"
View user's profile View All Posts By User
mabuse_
Hazard to Self
**




Posts: 56
Registered: 3-6-2010
Member Is Offline

Mood: No Mood

[*] posted on 23-1-2011 at 03:56


I'm interested too.

Are there any known facts about these compounds,
such as numbers for friction/impact sensitivity, lead block tests and Vdet? I can't find anything?

And isn't there any drawback I don't see at the moment?
If this stuff has such favorable properties, why are commercial blasting caps are still based on lead azide?
View user's profile View All Posts By User
quicksilver
International Hazard
*****




Posts: 1820
Registered: 7-9-2005
Location: Inches from the keyboard....
Member Is Offline

Mood: ~-=SWINGS=-~

[*] posted on 23-1-2011 at 07:30


The original clathrate concept* was invented by a Nun as a crystal within a crystal matrix. The azo element was a "stretching" of the NaN3 weight to expand the use of what was once a difficult to obtain material. It's elements in caps had a POSSIBLE drawback of reactivity to lead or copper. But it's extremely effective and has great yield. Possibly as little as 10th gram initiation weight (a bit more than straight lead azide but certainly less than most others). It seemingly had not been picked up commercially but this could be due to patent wars, etc.

* Conceptually.

That person's name may have been lost to history OR worked upon anonymously.

[Edited on 23-1-2011 by quicksilver]




View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 23-1-2011 at 15:37


http://www.sciencemadness.org/talk/viewthread.php?tid=389&am...

Sister Martinette Hagan aka Sister Mary Martinette Kathleen Hagan

"Clathrate Inclusion Compounds"
Hardcover: 189 pages
Publisher: New York: Reinhold Publishing 1962. (1962)
ASIN: B0000CLI8G
Shipping Weight: 1.7 pounds

original price $6.50
used copies good condition ~ $135.00
used copies fair condition ~ $25.00
http://www.mysteryandimagination.com/ap_hagan_martinette_sis...

http://pubs.acs.org/doi/pdf/10.1021/ed040pA222.2

[Edited on 24-1-2011 by Rosco Bodine]
View user's profile View All Posts By User
franklyn
International Hazard
*****




Posts: 3026
Registered: 30-5-2006
Location: Da Big Apple
Member Is Offline

Mood: No Mood

[*] posted on 23-1-2011 at 18:42
Enjoy


http://babel.hathitrust.org/cgi/pt?id=mdp.39015023160255
Clathrate Inclusion Compounds.gif - 20kB
View user's profile View All Posts By User
Bert
Super Administrator
*********




Posts: 2821
Registered: 12-3-2004
Member Is Offline

Mood: " I think we are all going to die. I think that love is an illusion. We are flawed, my darling".

[*] posted on 24-1-2011 at 12:36


Thanks for the various links, the original basic Lead picrate igniter patent had the solution strength/temp vs. crystal size information- I suspect I have been allowing the water volume to go too low now.

Going to need more supplies to pursue this.

I note Rosco's various refinements on mol size picric acid synthesis here:

http://www.sciencemadness.org/talk/viewthread.php?tid=4457&a...

And the Lead salts preparation thread here:

http://www.sciencemadness.org/talk/viewthread.php?tid=5490

(6 pages into it, haven't found what I'm looking for yet-)

I've got substantial amounts of Lead tetroxide on hand, and wonder if any have tried synthesis of Lead nitrate from red Lead oxide? All my metallic Lead has Tin, Antimony and probably a bit of Arsenic alloyed with it. Good for bullets, not so much for chemistry I'm thinking.

(edit)
Ah, yes.

Pb3O4 + 4HNO3 ~~~> PbO2 + 2H2O + 2Pb(NO3)2

Filter out the Lead oxide and crystalize the Lead nitrate from solution.


[Edited on 24-1-2011 by Bert]
View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 24-1-2011 at 13:29


Actually there are things that could probably make the synthesis easier,
and doubling or tripling the dilution is something worth trying, because of the low solubility intermediates. Another variation is the use of a centrifugal impeller type of stirring head which has a central inlet tube descending to nearly the bottom of the flask or beaker where the inlet current of liquid would tend to keep solids in a loop circulation, being suctioned from the bottom where they settle and rising in the current of liquid being spun out into the upper vortex by the hollow impeller disc. Keeping solids in suspension during this synthesis is similar to the problem with reactions using iron filings, the heavy particles are difficult to keep suspended in the liquid phase. I have used a mag stirrer in combination with
a propeller like a little model boat propeller on the end of stirrer shaft from above, both running at high speed, to keep the solids in suspension and prevent dunes of solids accumulating on the bottom. You do need a good loop circulation
going to keep the particles in suspension.
View user's profile View All Posts By User
Hennig Brand
International Hazard
*****




Posts: 1284
Registered: 7-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 12-8-2011 at 11:37


Here is slide 19 and 20 from a presentation put on by the Beijing Institute of Technology in 2010. Sounds like they might be talking about our azo-clathrate, or something similar when they describe the multiple salt.

From Primary Explosive Presentation in China.jpg - 149kB From Primary Explosive Presentation in China next page.jpg - 186kB

The Lead Styphnate/ Lead Azide co-precipitate looks interesting. I believe Microtek made this (it might have been a long time ago at E&W), but he said he was unsure if it was a double salt or just a co-precipitate.

Here is the link to the full set of slides from the presentation.
http://www.cecd.umd.edu/documents/presentations/Hong-Kong/Zh...



edit:
I may have misquoted Microtek (it was a while since I read that post), and I may be misusing the term co-precipitation. It seems there are several different kinds of co-precipitation.


[Edited on 13-8-2011 by Hennig Brand]
View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 12-8-2011 at 12:37


How about that, it sure is likely to be the clathrate having those three compounds in one composition. It is good that current research is being done. There are very probably at least a few useful energetic compounds yet to be identified and some of these may have practical value.
View user's profile View All Posts By User
Hennig Brand
International Hazard
*****




Posts: 1284
Registered: 7-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 13-8-2011 at 07:14


How should the clathrate behave when a small quantity of the loose powder is lit? Should it behave just like Lead Azide and detonate even in tiny amounts?

I am experimenting a bit, but I think I need to get some higher quality Picric Acid. I started with only 1g of Picric Acid instead of 4.6g, and scaled the quantities of the other reagents accordingly. I did however use the same amount of distilled water as the full scale synthesis called for, and used the same addition rates as well. My yield was only 90% of what Mr. Anonymous got. I imagine I am having the same trouble with my Picric Acid that I had before when trying to make Basic Lead Picrate.

Here is a picture of my yield. The picture doesn' t show it but, if held up to the light it is millions of sparkly crystals.

Azo-Clathrate.JPG - 289kB

[Edited on 13-8-2011 by Hennig Brand]
View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 13-8-2011 at 08:05


By color I can tell you that isn't it. The color should be close to the same color as rust an orange brown color.
View user's profile View All Posts By User
Hennig Brand
International Hazard
*****




Posts: 1284
Registered: 7-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 13-8-2011 at 10:49


Same trouble I was having over a year ago with the Basic Lead Picrate synthesis, I think. I will get a better sample of Picric Acid and try again, thanks.
View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 13-8-2011 at 11:08


Yeah I was looking at that from last July where quicksilver posted a picture of what the basic lead picrate substrate looks like
http://www.sciencemadness.org/talk/viewthread.php?tid=389&am...
and that is a bit darker but not far distant from the color of the azo-clathrate which is somewhat lighter and more orange looking, and is actually derived from the basic lead picrate which forms first.
The post about Three Basic Igniters also has relevance.
http://www.sciencemadness.org/talk/viewthread.php?tid=389&am...
There really truly is a process chemistry involved which is essential in terms of the temperatures, and stirring and slow addition requirement ....it must be very precisely done or it simply won't work. Chemistry has governing subtleties for
certain reactions and those definitely are in effect here, and can't be fudged or avoided. If the process is not strictly followed .....the end product will not be the same. I have often been dismayed at how so many other people will perform an experiment I have described with precision, but will vary some parameter because of estimating it really shouldn't change the outcome ....but it does. I'm not even sure myself why that would happen for some of these things, but that doesn't mean it doesn't happen differently when a parameter is changed in some reactions, while in other reactions it may do no harm. I haven't really done any extensive "failure analysis" about what doesn't work, because my focus and energy has been directed at what does seem to work. You could probably write encyclopedic volumes about all the reactions that didn't go as planned compared to the few notebooks containing reactions that do go well .....and life is short.

That Chinese report mentioned "formed quantitatively" which concurs with my experience and makes me pretty sure they were duplicating what I reported here. But I would differ with the "basic lead azide" component although it may be possible it is there.....maybe they found that by analysis as a "permutation" I missed in the theoretical analysis and stoichiometry predicting the formula. I never did an actual elemental analysis of the product and I'm not sure how reliable it would be with that level of specificity anyway.

As for how it behaves on ignition it is not as unequivocal as lead azide for small amounts it has a larger critical mass so it is substantially more tame than pure lead azide. It is not as proportionally more tame than would directly correlate with its proportional content of lead azide, because of a synergistic effect. There is a definte performance penalty for initiating capacity and critical mass compared to lead azide. If you want lead azide you can make lead azide. The azo-clathrate is not meant to be a substitute lead azide, but is a stable variant which has been "detuned" to gain chemical stability and easier ignition ....so there is a price paid on performance in the initiating ability compared to straight lead azide. For some uses then the lead azide will be superior, but for other reasons for other applications the azo-clathrate will be superior. Designers choice is the name of that scenario.


[Edited on 13-8-2011 by Rosco Bodine]
View user's profile View All Posts By User
Hennig Brand
International Hazard
*****




Posts: 1284
Registered: 7-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 13-8-2011 at 16:38


It took a lot of patience but, I think I followed the procedure very closely except for the much greater dilution. I don' t think the greater dilution would hurt however. I think you mentioned that dilution might make things easier even. I am working on some new picric acid as I write this. I have been known to cut a few corners, but I would be surprised if the problem isn' t with my picric acid. I think I screwed up the picric acid synthesis last July during the sulfonation.

The azo-clathrate sounds like it makes very good use of a valuable resource (sodium azide).
View user's profile View All Posts By User
Rosco Bodine
Banned





Posts: 6370
Registered: 29-9-2004
Member Is Offline

Mood: analytical

[*] posted on 13-8-2011 at 18:35


Did the intermediate basic lead picrate or possible basic lead picrate / lead nitrate double salt have the rust coloration before the addition of the sodium azide was begun ? That would be pretty definitive unless you somehow had the proportions for the bis basic lead picrate lead nitrate compound mentioned in that second patent of the three .....because that yellow color for the bis compound is more identical to what you show .....a bright yellow. The clathrate is more of reddish brown nearer to a lead styphnate color. I haven't tried the greater dilution so that may be the difference.

[Edited on 14-8-2011 by Rosco Bodine]
View user's profile View All Posts By User
Hennig Brand
International Hazard
*****




Posts: 1284
Registered: 7-6-2009
Member Is Offline

Mood: No Mood

[*] posted on 13-8-2011 at 20:08


No, it did not get the proper color before the addition of the sodium azide. It did go a bit orange but not as much as the description in the synthesis said it should. I forgot to mention that.

I used the proportions and procedure from the Mr. Anonymous synthesis posted at the start of this thread.

I have made a little picric acid directly from phenol, we will see if that makes a difference. I will try and do a little testing tomorrow.

[Edited on 14-8-2011 by Hennig Brand]
View user's profile View All Posts By User
 Pages:  1    3  4

  Go To Top