Sciencemadness Discussion Board

Can small quantities of nitrocellulose detonate?

Fusionfire - 9-9-2011 at 02:00

As someone still working on my practical nitration experience, I enjoy nitrocellulose. The nitration process is benign and the product itself predictable and difficult to detonate - unlike say nitroglycerin ;)

But is it possible to get NC to detonate? How would you achieve SDT or DDT with it?

For small quantities, I'm thinking that loose nitrated cotton won't be able to SDT/DDT - it has to be compacted so a shock can self-propagate and self-reinforce through it. In addition it should be confined, so we are probably looking at a hard NC rod made by dissolving NC in acetone in a filter paper tube and drying it off, then putting the nearly pure NC rod in a metal tube. Primer at one end for SDT or light it with a pyrotechnic fuze for DDT.

BTW if someone with institutional access could share these documents with us, I would be grateful :)

Experiments on the transition deflagration-detonation of propellants
R. Frauenfelder
http://dx.doi.org/10.1002/prep.830080604

[Edited on 9-9-2011 by Fusionfire]

Bot0nist - 9-9-2011 at 04:47

I doubt it will DDT, even when compressed and confined unless you are dealing with very large amounts. I have detonated cellulose nitrate before, but I had to use a large and powerful booster(TNP) along with my primary to get repeatable results. Do some tests. I bet a good primary explosive in a well designed cap, or a compound cap with a strong and sensitive secondary at optimum densities is what could work on small scales.

[Edited on 9-9-2011 by Bot0nist]

Blasty - 9-9-2011 at 06:13

Quote: Originally posted by Fusionfire  
As someone still working on my practical nitration experience, I enjoy nitrocellulose. The nitration process is benign and the product itself predictable and difficult to detonate - unlike say nitroglycerin ;)

But is it possible to get NC to detonate? How would you achieve SDT or DDT with it?

For small quantities, I'm thinking that loose nitrated cotton won't be able to SDT/DDT - it has to be compacted so a shock can self-propagate and self-reinforce through it. In addition it should be confined, so we are probably looking at a hard NC rod made by dissolving NC in acetone in a filter paper tube and drying it off, then putting the nearly pure NC rod in a metal tube. Primer at one end for SDT or light it with a pyrotechnic fuze for DDT.


By initiating it with just a flame/spark it needs large quantities of it to explode unconfined. If strongly confined, smaller quantities of it will explode and burst the container to pieces, similar as black powder does under the same conditions.

For detonation using a blasting cap, the minimum amount required seems to be roughly 7 grams of it (and not in the "fluffy" form when the cotton is nitrated, but finely divided and compressed), according to Abel's interesting experiments with it:

http://www.sciencemadness.org/talk/viewthread.php?tid=13283&...

quicksilver - 9-9-2011 at 06:15

-=IF=- you can get a true 13% NC you will see some interesting impact dets if a small (50-100mg) piece were compressed tightly and swatted w/ a hammer on a heavy steel surface (wrapped in foil: use eye protection always). 12% is functional but does not act like 13%. The collodinal phenomenon starts at about 12% and several grams might be initiated if contained and the train made in a manner of acute contact but it's at 13% that NC yields up all the interesting phenomenon such as the Munroe effect, etc.
Often this not only requires significant mixed acids but the use of a type of cellulose that will allow (acid) contact though-out it's mass.

Blasty - 9-9-2011 at 06:15

Quote: Originally posted by Bot0nist  
I doubt it will DDT, even when compressed and confined unless you are dealing with very large amounts. I have detonated cellulose nitrate before, but I had to use a large and powerful booster(TNP) along with my primary to get repeatable results. Do some tests. I bet a good primary explosive in a well designed cap, or a compound cap with a strong and sensitive secondary at optimum densities is what could work on small scales.


Let me ask you again, since I did not get an answer in the other thread:

Was this nitrocellulose you detonated made from cotton or from some sort of already powdered cellulose?

Bot0nist - 9-9-2011 at 07:02

Blasty, sorry, I must of missed that question in the other thread. The nitrocellulose that was able to detonate was made from regular cheap cotton balls that were pulled apart. They were nitrated in the same rough manner that I laid out in the other thread. Nitrated twice, using NH<sub>4</sub>NO<sub>3</sub> as the nitrate salt.

No impact tests were done, though I should have. I never really thought to try that on cellulose nitrate. I imagine the cellulose nitrate I had was < 13% N, based on my difficulties with preformance, and so not the 'hexanitrate' I had falsely believed it to be. Still it makes a great fast burning lacquer, dropping small balls of it over a lit match really impresses the kids, and it is a really fun nitration.



Edited: to remove any occurrence of sounding practical.

[Edited on 9-9-2011 by Bot0nist]

The WiZard is In - 9-9-2011 at 08:55

Quote: Originally posted by Fusionfire  
As someone still working on my practical nitration experience, I enjoy nitrocellulose. The nitration process is benign and the product itself predictable and difficult to detonate - unlike say nitroglycerin ;)

But is it possible to get NC to detonate? How would you achieve SDT or DDT with it?



Well .... I have good reason to beleive that if you nitrate
a cotton ball from the drugstore, roll it into a pill between your
fingers and put it on a hard surface e.g., the anvil on your vise.
Then hit it with a hammer it will snap. You could ramp
this up. Please observe the obvious precautions to keep spall out of your nose &c.

Me The Analogue Guy owns a original copy of this —
you can DL yours from Google.com/books.


Compressed Gun Cotton for Military Use

TRANSLATED FROM THE GERMAN of MAX VON FORSTER WITH AN INTRODUCTION MODERN GUN COTTON, MANUFACTURE, PROPERTIES AND ANALYSIS. BY Lieut JOHN P. WISSER, USA NEW YORK: I). VAN NOSTRAND, PUBLISHER, 23 Murray and 27 Warren Streets. 1886.



[Edited on 9-9-2011 by The WiZard is In]

Mildronate - 9-9-2011 at 11:10

I had tryed it with hummer it works

Blasty - 9-9-2011 at 20:23

Quote: Originally posted by Bot0nist  
Blasty, sorry, I must of missed that question in the other thread. The nitrocellulose that was able to detonate was made from regular cheap cotton balls that were pulled apart. They were nitrated in the same rough manner that I laid out in the other thread. Nitrated twice, using NH<sub>4</sub>NO<sub>3</sub> as the nitrate salt.


How did you reduce the nitrocellulose to powder? My understanding from reading Abel's experiments on it is that in its regular cotton-like form it simply will not detonate by means of a blasting cap. It needs to be reduced to finer particles and compressed. However, achieving this reduction to powder without the specialized machinery those guys had access to is not as easy as some would think. This is why if any of those cellulose powders easily available nowadays gave as good a result as nitrating cotton it would save a lot of time and trouble for the experimenter without access to the specialized machinery.

Bot0nist - 9-9-2011 at 20:31

I didn't reduce it to a powder. It was in smallish pieces and pressed with a c-clamp. I didn't det with a blasting cap, but with a large booster.

[Edited on 10-9-2011 by Bot0nist]

quicksilver - 10-9-2011 at 08:42

If curiosities of a "snap-cap" type are of interest it's much easier to work with a nitro-starch type material. When examined it's obvious that there are differences in various cellulose products and therefore our end product. The same is true with starch. Tapioca starch is chemically differentiated from corn, etc. However it appears that (especially Tapioca) nitrates easier and to a higher degree.
Some years back I had experimented with nitrocellulose and found that the type of toilet paper that was made for recreational vehicles or septic systems (that comes apart VERY quickly within minimal water) was perhaps a better source of highly purified material than medical "cotton" and responded to mixed acids more completely. The starches appeared to reach a higher level easily & from a curiosities sake, I found them very efficient.
A great of written material is available on nitro-starch as it became a TNT substitute during WWII and was seemingly as effective. It was even packaged in the same manner.

Fusionfire - 10-9-2011 at 13:25

Alright guys I tried hitting a small tightly rolled ball of NC (about the size of a soy bean or cotton bud tip) made from nitrated cotton wool between a hammer and a concrete paving slab, several times. It did not detonate.

I prepared the NC through the mixed acid approach in an ice bath:
70ml H2SO4 (96%)
30ml HNO3 (70%)
5g cotton wool
45 mins later, washed and neutralised in NaHCO3

Should I be using a nitrate salt instead of 70% HNO3 (or more concentrated nitric acid) to get a higher degree of nitration?

Happy to post pictures or videos upon request if you think it'd help.

Bot0nist - 10-9-2011 at 13:28

Try on a steel anvil. Concrete isn't smooth or hard enough IIRC.

Fusionfire - 10-9-2011 at 15:39

Quote:
If curiosities of a "snap-cap" type are of interest it's much easier to work with a nitro-starch type material. When examined it's obvious that there are differences in various cellulose products and therefore our end product. The same is true with starch. Tapioca starch is chemically differentiated from corn, etc. However it appears that (especially Tapioca) nitrates easier and to a higher degree.


Interesting. I wonder if it is because there are more -OH groups (compared to carbon atoms) to nitrate in tapioca starch? NG has a 1:1 -OH to C ratio :)

Quote:

Some years back I had experimented with nitrocellulose and found that the type of toilet paper that was made for recreational vehicles or septic systems (that comes apart VERY quickly within minimal water) was perhaps a better source of highly purified material than medical "cotton" and responded to mixed acids more completely. The starches appeared to reach a higher level easily & from a curiosities sake, I found them very efficient.


I tried grinding dried nitrated toilet paper in a mortar & pestle to no success. It appears the same as normal toilet paper, except it had a slight yellow tinge and felt a bit stiffer. Cosmetic cotton wool doesn't seem to yellow as much on nitration.

I think the best way to get NC powder is to nitrate fine sawdust and add some kind of anti-caking agent, e.g. PTFE spray (beware toxic fumes on combustion).

Or you could blend toilet paper with some water, let it dry out, nitrate that and let the nitrated slurry dry + set in a porous mould.

Quote:

A great of written material is available on nitro-starch as it became a TNT substitute during WWII and was seemingly as effective. It was even packaged in the same manner.


Is there a chemical reason for why nitrostarch explodes better than nitrocellulose? They are basically organic polymers with -OH groups that are substituted for -ONO2 groups.



[Edited on 10-9-2011 by Fusionfire]

Fusionfire - 10-9-2011 at 15:40

Quote: Originally posted by Bot0nist  
Try on a steel anvil. Concrete isn't smooth or hard enough IIRC.


Alright will give it a shot tomorrow and report back :)

Will also try sensitising it with a few specks of sand.

Blasty - 10-9-2011 at 19:50

Quote: Originally posted by Fusionfire  
Alright guys I tried hitting a small tightly rolled ball of NC (about the size of a soy bean or cotton bud tip) made from nitrated cotton wool between a hammer and a concrete paving slab, several times. It did not detonate.

I prepared the NC through the mixed acid approach in an ice bath:
70ml H2SO4 (96%)
30ml HNO3 (70%)
5g cotton wool
45 mins later, washed and neutralised in NaHCO3

Should I be using a nitrate salt instead of 70% HNO3 (or more concentrated nitric acid) to get a higher degree of nitration?

Happy to post pictures or videos upon request if you think it'd help.


Your nitric acid has too much water. You need to concentrate it to get a better product.

Blasty - 10-9-2011 at 20:04

Quote: Originally posted by Fusionfire  
I think the best way to get NC powder is to nitrate fine sawdust and add some kind of anti-caking agent, e.g. PTFE spray (beware toxic fumes on combustion).

Or you could blend toilet paper with some water, let it dry out, nitrate that and let the nitrated slurry dry + set in a porous mould.


A while back I tried putting wet nitrated cotton + some more water in a blender to see if it could "pulp" it, but the results were not very satisfactory. It did reduce the nitrated cotton to a more compact form but not to the point of an amorphous pulp. Perhaps this method would work better with a nitrated paper that is mostly cellulose with little impurities.


[Edited on 11-9-2011 by Blasty]

quicksilver - 11-9-2011 at 07:41

I agree. Too much H2O won't get you to 13%. Should you try a mixed acid w/ a solid nitrate, take time to get a clear clean solution from your mix. If using prills or anything that should be "lumpy" then do your best to reduce to to a fine mesh powder and mix in slow, equal amounts. Using pre-cooled H2SO4 make that solution clear in it's mixing, etc. Heating your sulfuric acid down should also rid it of excess water should you be using a lower grade of acid to begin with.

Nitro-starch is interesting from many of the same standpoints NC is. It is a complex precursor (& also needs a high % acid) yet it appears to carry a higher percentage of nitrogen in the final product. Davis had some material on NS and almost every author who wrote of extensive nitrated esters from the 1940's and earlier had something to say about it. The material begins as very tiny individuated particulate and this physical attribute MAY have an influence on it's strength. As for chemical reasons why it should carry a higher level of nitrogen, several concepts have been explored. Materials that begin with H (or OH groups) might have more available "room" for the bonding with N in esterfication. It's obvious that it is a more complex material than cellulose. I was going to find a book "Military Explosives" (Weaver) where I think a bit more is written. Several authors have written that corn (starch) has greater potential yet Tapioca is easier (in terms of N bonding). This may simply be a phenomenon of the physical characteristics or both as corn appears to "float" on top of the acid without effort made to mix with consistency as it is a micro particulate (6-2 um). It had seen extensive use. However I have read a variety of counter-point ideas as to why it was employed successfully.

Fusionfire - 11-9-2011 at 09:01

Quote:


Alright will give it a shot tomorrow and report back :)

Will also try sensitising it with a few specks of sand.


Alright I whacked it between a hammer and the top of a steel vise. After a few attempts, I heard a very small crack but not all the NC was consumed.

Assuming it was a small detonation I heard, it appears that NC is capable of undergoing SDT but not capable of self-sustaining detonation throughout its bulk.

I liked nitrating cellulose because I didn't have to distill 70% HNO3 to get RFNA/WFNA for a usable product to play with. But using a nitrate salt to get a nearly anhydrous nitrating mixture in lieu of RFNA/WFNA is more convenient....

The WiZard is In - 11-9-2011 at 09:42

Quote: Originally posted by Fusionfire  


Alright I whacked it between a hammer and the top of a steel vise. After a few attempts, I heard a very small crack but not all the NC was consumed.

I liked nitrating cellulose because I didn't have to distill 70% HNO3 to get RFNA/WFNA for a usable product to play with. But using a nitrate salt to get a nearly anhydrous nitrating mixture in lieu of RFNA/WFNA is more convenient....


This method works for me on la vise.

This from a page removed from a chemistry book by
me maybe 50 years ago. It has been kitchen tested
a number of times.

In a 250-cc beaker mix carefully [For saftey
sake do as you ought'r - add the acid to the water.], exactly
10 cc of water 68 cc. of concd. sulfuric acid, and 30 cc. of concd. nitric
acid. Cool the solution to 30o and introduce 1 g of absorbent
cotton, in a single piece. Stir the mixture from time to time
and maintain at a temperature of 30o for twenty minutes.
At the end this time remove the nitrate cotton by means
of a glass rod and transfer immediately to a large volume of
cold water. Wash thoroughly with cold water, and finally
warm water, until washings do not show an acid reaction
to litmus paper. Squeeze ad dry as possible and spread out
to dry in the air, at room temperature. The product
obtained in this way contains about 11.0 per cent nitrogen.

NB - The litmus test is close to useless. If you intend (though
I don't know why you would) store it. Either boil it for several
day changing water several times or treat it with urea.

I recommend doing this out of doors, the fumes emitted are annoying.

Checking Google.com/books, I believe this was extracted
from—
Laboratory experiments in organic chemistry
By Roger Adams, John Raven Johnson, Charles F. Wilcox.
Numerous editions.


The WiZard is In - 11-9-2011 at 11:44

Quote: Originally posted by quicksilver  
If curiosities of a "snap-cap" type are of interest it's much easier to work with a nitro-starch type material. When examined it's obvious that there are differences in various cellulose products and therefore our end product. The same is true with starch. Tapioca starch is chemically differentiated from corn, etc. However it appears that (especially Tapioca) nitrates easier and to a higher degree.
Some years back I had experimented with nitrocellulose and found that the type of toilet paper that was made for recreational vehicles or septic systems (that comes apart VERY quickly within minimal water) was perhaps a better source of highly purified material than medical "cotton" and responded to mixed acids more completely. The starches appeared to reach a higher level easily & from a curiosities sake, I found them very efficient.
A great of written material is available on nitro-starch as it became a TNT substitute during WWII and was seemingly as effective. It was even packaged in the same manner.




Nitrostarch?! Forsooth. When nitrostarch walks into the room
real explosives like TNT laugh at it for its obvious disadvantage
as an explosive.

Not what I was thinks of here are a few more courtesy of
Köhler and Meyer's 6th.

Nitrostarch
Nitrostärke; nitrate d’amidon
[C6H7O2(ONO2)3]n
pale yellow powder
empirical formula of the structural unit: C6H7N3O9
oxygen balance at 12.2% N: –35%
density: 1.6 g/cm3
maximum value attainable by pressing: 1.1 g/cm3
lead block test: 356 cm3/10 g
deflagration point: 183 °C = 361 °F
impact sensitivity: 1.1 kp m = 11 Nm
Nitrostarch is insoluble in water and ether, but is soluble in ether
alcohol mixtures and in acetone.
Nitrostarch, with various nitrogen contents (12–13.3%), is prepared by
nitration of starch with nitric acid or nitrating mixtures. The resulting
crude product is washed in cold water and is then dried at 35– 40 °C.
Nitrostarch resembles nitrocellulose in several respects, but, owing to
its poor stability, difficulty in preparation and hygroscopicity, it is not
used anywhere outside the USA. “Headache-free” industrial explosives
are based on nitrostarch.


This from— TM 9-1910 Military Explosives April 1955

Nitrostarch-1.jpg - 323kB Nitrostarch-2.jpg - 602kB Nitrostarch-3.jpg - 469kB

For more than you probable want to know 'bout nitrostarch see

Urbanski II p. 418-438

Byda Urbanski's ref [23] can be read in part at Google.com/books. The least expensive copy of the
book I locate is US $49. This exceeds the books cost
vs value
requirement.

Nitrostarch mas

The WiZard is In - 11-9-2011 at 11:54

From PATR-2700



Attachment: PATR 2700 Nitrostrarch.pdf (1.1MB)
This file has been downloaded 857 times


Mydtys - 11-9-2011 at 22:15

Use acetone. hit the dry NC with hammer... then you'll be surprised

Fusionfire - 11-9-2011 at 23:40

Quote: Originally posted by Mydtys  
Use acetone. hit the dry NC with hammer... then you'll be surprised


You mean use acetone to dissolve the NC and dry it in a mould into a pill?

Bot0nist - 12-9-2011 at 03:34

Yes, I believe that is what he is talking about. It is even possible to roll the sticky goop up between your fingers and form a little ball. Or, you can pour it between some foil to make a little plastic sheet that can be cut into little pieces when dry. It takes a little while for it to dry thoroughly. Make sure your acetone is water free.

Fusionfire - 12-9-2011 at 04:09

Quote: Originally posted by Bot0nist  
Yes, I believe that is what he is talking about. It is even possible to roll the sticky goop up between your fingers and form a little ball. Or, you can pour it between some foil to make a little plastic sheet that can be cut into little pieces when dry. It takes a little while for it to dry thoroughly. Make sure your acetone is water free.


Alright I dissolved nitrated cotton wool in some 99.5% acetone, just enough to get a jelly like consistency.

I then poured/scraped the mass using a spatula onto a non-stick tray in a long (roughly) rectangular smear.

I'll break off small bits once it dries/hardens and try whacking them with a hammer.

Has anyone tried to put NC dissolved in acetone into an atomiser and spraying it to get NC powder? :D

AndersHoveland - 13-9-2011 at 12:40

I have often read that cellulose nitrate is capable of detonation by itself, but one would think the substance must be fairly resistant to detonation, as it is was used as a propellent in large diameter canons, and in the form of cordite. Obviously it would be unsuitable for this purpose if it was vulnerable to detonation. We can see that cordite is formed into ribbons to give it a high surface area, to maximise the rate of deflagration. If it only detonated, then surface area would not matter.

Fist sized quantities of cellulose nitrate, when saturated with sensitized nitromethane, can be detonated with a few grams of primary.

As has been previously discussed on this forum, two hammers that have been coated in a nitrocellulose lacquer make loud little pops, and some smoke, when hit together. The same was sometimes the case with nitrocellulose billiard balls. So nitrocellulose (cellulose nitrate) is in fact known to detonate from sharp impact. It seems to be that the harder, more compact forms, are much more vulnerable to mechanical impact than the softer lower-density forms. Supposedly a nail can be hammered into cordite (which also contains a portion of nitrogycerin!) with virtually no danger. It seems that the physical rpperties of the nitrocellulose in question are very important in relation to sensitivity, as cordite is soft and flexible.

quicksilver - 2-10-2011 at 14:14

Although even Federoff declares that many nitrostarch preparations are embodied in "trade secret" preparations I had managed to find some patents using NS in unique formats. To include them & keep it under 2Mb I enclosed the raw .tiff files.
The PATR states that cornstarch is the common material, yet for ease of nitration, several experimenters insist that Tapioca starch is best. Apparently the extreme small size of the particulate makes the corn starch adhere and "clump together". From my limited microscope measurement slide it seems that the particulate can drop as low as 2um. The original (and common synthesis is the utilization of an addition of starch to HNO3 w/ the addition of H2SO4, while others insist on a mixed acid with high strength nitric acid. Nitrogen content varies quite a bit (more than NC) from 11% through 15%. An interesting feature is the lack of the "nitro-headache" similar to the solid alcohols.
Synthesis appears to require small additions over a protracted period of time with the total contact within the acids of nearly two hours.

Nitro starch was used fairly extensively during WWII as a substitute for TNT and even packaged as TNT blocks in 1/4, 1/2 and 1 lbs blocks. NS was often used as a "work-oriented", high brisency explosive and to much less an extent as a weapon.
As many know, the "trade secret" addendum to many patents make idiosyncrasies difficult to discern. Therefore any synthesis should always start in very low eights so as to maintain safety AND to record efficiency in synthesis. Additions should be of low weight (<.25gr). There is limited information regarding the "run-a-way" phenomenon. But a cautionary note here demands attention. Occasional sever oxidation & fire danger may accompany the use of corn starch due to "clumping" affect. Several authors (including Federoff, comment on the two stage nitration. This (perhaps) to prepare small particulate material to divide and compliment exposure to the acids.

Having seen corn starch nitration I can attest that the material is not optimum. Yet corn starch has less fats and oils displayed in microscopic examination. I had long been interested in NS as it's production appeared shrouded in secrecy. but this may be both a war-time agenda and a profit making attempt as it's utilization has much to be said for it. It is said to have little to no headache, very high shattering power, and excellent Monroe effect applicability. It is a very simple synthesis, similar to solid the solid alcohols such as ETN. It's downside include the need for anti-acids, UV and temperature control.
The raw patents contain a wealth of information, including background information, authors, & testing under industrial conditions. Superficially it appears to be well suited for industrial applications; yet it's popularity was during conflict periods. NS synthesis should NOT be attempted without a solid background in polyol nitration.
That it does not promote a "nitro headache" does not mean that it is non-toxic nor act upon the circulatory system. It is an extremely brisant material with high VoD & shattering effect with minimal compression.
Neutralization is not accomplished easily as it does not form a crystal that gives access to it's particulate body.

Attachment: NITROSTARCH.rar (1.1MB)
This file has been downloaded 454 times