right...i made up some Nitrocellulose today using conc sulphuric and nitric acid...i am wanting to use it as a rocket propellant, i havnt been able to find much information on this being used as a rocket propellant, so i just wondered if anyone on here has had any experience with NC as a rocket propellant?i will be waiting for it to dry until tomorow then i will be trying it out in a small rocket. does it need to be compressed?and if so, is it to be compressed the usual way with a metal rammer and hammer or just compressed with your strength and no pounding?or simply let loose in there? Cheers for any advice/info;)
P.S. maybe this should go i the high explosive and special FX forum?
[Edited on 29-7-2003 by Pyromaster2003]
Nitrocellulose
Started by Pyromaster2003, Jul 29 2003 07:33 PM
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#1
Pyromaster2003
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Posted 29 July 2003 - 07:33 PM
#2
bernie
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Posted 29 July 2003 - 08:55 PM
Hmmmmmm, I've never heard of it myself. Sounds a little hairy to me. My only suggestion is to try it in a very small itty bitty rocket.
#3
adamw
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Posted 29 July 2003 - 09:07 PM
Hmmm, before you embark on a calorie-burning pounding session I think it would be wise to wash the NC several times with a distilled water / sodium bicarb solution to get rid of any acid. Steaming it several time and then washing it loads would be better, but since (I hope) you wont be keeping it for long, it shouldnt be nessecary.
#4
smpip
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Posted 29 July 2003 - 09:33 PM
Do you have a transparent disc of Nitro cellulose or do you have fibre's of Nitro-cotton?
This stuff goes off with a bang, any confinement would result in a bang, when it is lite in the open, it will give off a flash of brilliant white light that has been known to knacker the CMOS chip (lens) in digital cameras used to take a snap shot, the cleaning process is to reduce the chance of spontaneous ignition, (reduce, not stop) and to help reduce the risks involved with the storage of this stuff, when Nitrocellulose was used as a film medium, it was a requirement that the film booths at cinemas could automatically be sealed off from the rest of the building, we are talking concrete walls, steel doors/shutters on the projector windows, and that was only film, the projectionist was not mean't to get out.
Nitro-cellulose is used as a propellent for bullets, even if I did know the strengths of your acid/mix, I would tell you to leave alone.
Your presence here on the forum is welcomed and wanted, making mistakes is part of growing up, however some mistakes should never be made.
This stuff goes off with a bang, any confinement would result in a bang, when it is lite in the open, it will give off a flash of brilliant white light that has been known to knacker the CMOS chip (lens) in digital cameras used to take a snap shot, the cleaning process is to reduce the chance of spontaneous ignition, (reduce, not stop) and to help reduce the risks involved with the storage of this stuff, when Nitrocellulose was used as a film medium, it was a requirement that the film booths at cinemas could automatically be sealed off from the rest of the building, we are talking concrete walls, steel doors/shutters on the projector windows, and that was only film, the projectionist was not mean't to get out.
Nitro-cellulose is used as a propellent for bullets, even if I did know the strengths of your acid/mix, I would tell you to leave alone.
Your presence here on the forum is welcomed and wanted, making mistakes is part of growing up, however some mistakes should never be made.
#5
Pyromaster2003
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Posted 29 July 2003 - 10:44 PM
thanks for that advice Adam but i already did that, dont have distilled water but i soaked in a saturated solution of sodium bicarbonate until no more carbon dioxide bubbles appeared.
ahha i finally found a guy out there who knows about NC, thats for all that smpip. il explain the exact procedure i carried forward...50%-50% or 98% H2SO4 and 70%nitric acid, mixed slowly in an ice bath. one 100% pure cotton pad, nitrated for half an hour. dipped into saturated sodium bicarb solution for 5 mins. then washed under tap water for 5 mins and squeezed out and left to dry.
this wont work as a rocket propellant?i may try anyway and report back tomorow. Thanks you 2 guys;)
ahha i finally found a guy out there who knows about NC, thats for all that smpip. il explain the exact procedure i carried forward...50%-50% or 98% H2SO4 and 70%nitric acid, mixed slowly in an ice bath. one 100% pure cotton pad, nitrated for half an hour. dipped into saturated sodium bicarb solution for 5 mins. then washed under tap water for 5 mins and squeezed out and left to dry.
this wont work as a rocket propellant?i may try anyway and report back tomorow. Thanks you 2 guys;)
#6
Nick
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Posted 30 July 2003 - 12:04 PM
DO NOT TRY TO USE FLUFFY NC AS A ROCKET PROPELLANT!!!!
If you do your rocket won't just go up, it'll go all over the place in little tiny pieces.
Also, DO NOT TRY TO RAM IT!!!!
Apart from the fact that the fibres are kinda spongy, and won't stay well rammed enough for it to burn at a moderate speed, I have seen a physics demo in which cotton wool (not nitrated) is ignited by putting it in a sealed tube and effectively ramming it in much the same way as a rocket would be rammed. The air spaces are compressed, the air heats up, and ignites the cotton. NC ignites at a much lower temperature than cotton, and will burn fast enough to shoot the ram out of the tube at a dangerous speed. Normally this isn't a problem when rammin powders, since the don't have many air spaces, but a fluffy ball of NC DOES!
A method for using it which was posted by a member called Microtek at www.roguesci.org/theforum is roughly as follows: firstly, dissolve the NC in acetone to make a thick syrup. Finely powdered urea can be added if you like, it is a stabiliser which greatly slows down the self-accelerating decomposition by eating up any NOx formed. Spread the syrup out on a clean, smooth surface (perhaps dusted with flour to prevent it from sticking), to an even thickness of a mm or two. Let it dry almost fully, then cut strips as wide as your rocket motor is long, and roll them up tightly around a thin bit of wooden dowel. You must roll it tightly or there will be air spaces between the layers which will make it burn too fast. Rolling it while slightly sticky will help with this, but if it is too sticky, voids will form inside the NC grain due to the acetone evapourating, and this will lead to an uneven burn and probably an explosion. You'll need to do some testing to get it right I imagine.
Anyway, after this you should have a cylinder of NC, with a core already present. Let it dry out fully, and then insert it into your rocket motor. You'll have to go to that Forum and search for the topic to find the exact method, but that is roughly it.
When making NC, try a 2:1 ratio of sulphuric to nitric, and the nitric will need to be about a 3-5 times excess based on the weight of cotton used.
Also, your washing is insufficient if you want to store it at all. First wash it thoroughly with water, then let it soak in a bicarb solution overnight, then wash it thoroughly with water again, and then dry it. That is a minimum.
If you do your rocket won't just go up, it'll go all over the place in little tiny pieces.
Also, DO NOT TRY TO RAM IT!!!!
Apart from the fact that the fibres are kinda spongy, and won't stay well rammed enough for it to burn at a moderate speed, I have seen a physics demo in which cotton wool (not nitrated) is ignited by putting it in a sealed tube and effectively ramming it in much the same way as a rocket would be rammed. The air spaces are compressed, the air heats up, and ignites the cotton. NC ignites at a much lower temperature than cotton, and will burn fast enough to shoot the ram out of the tube at a dangerous speed. Normally this isn't a problem when rammin powders, since the don't have many air spaces, but a fluffy ball of NC DOES!
A method for using it which was posted by a member called Microtek at www.roguesci.org/theforum is roughly as follows: firstly, dissolve the NC in acetone to make a thick syrup. Finely powdered urea can be added if you like, it is a stabiliser which greatly slows down the self-accelerating decomposition by eating up any NOx formed. Spread the syrup out on a clean, smooth surface (perhaps dusted with flour to prevent it from sticking), to an even thickness of a mm or two. Let it dry almost fully, then cut strips as wide as your rocket motor is long, and roll them up tightly around a thin bit of wooden dowel. You must roll it tightly or there will be air spaces between the layers which will make it burn too fast. Rolling it while slightly sticky will help with this, but if it is too sticky, voids will form inside the NC grain due to the acetone evapourating, and this will lead to an uneven burn and probably an explosion. You'll need to do some testing to get it right I imagine.
Anyway, after this you should have a cylinder of NC, with a core already present. Let it dry out fully, and then insert it into your rocket motor. You'll have to go to that Forum and search for the topic to find the exact method, but that is roughly it.
When making NC, try a 2:1 ratio of sulphuric to nitric, and the nitric will need to be about a 3-5 times excess based on the weight of cotton used.
Also, your washing is insufficient if you want to store it at all. First wash it thoroughly with water, then let it soak in a bicarb solution overnight, then wash it thoroughly with water again, and then dry it. That is a minimum.
#7
Pyromaster2003
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Posted 30 July 2003 - 01:08 PM
ok thank you very much for that quality info. thats very interesting about the cotton setting alight. so if i squash the NC with my fingers it will most likely ignite? NC dissolved in acetone is nitrocellulose lacquer isnt it? i am doing a test atm with a piece of NC its not fluffy btw(doesnt look it anyway, more solid ish) and iv placed the NC on a wooden board out in the SUN in the middle of my garden to see if it will deflagrate of detonate.
i think this will just deflagrate fast if i place some in a paper tube and ignite with a fuse?i thought the ratio for acids in the nitrating mixture was 1-1?
anyway, im off to try some experiments, cya
i think this will just deflagrate fast if i place some in a paper tube and ignite with a fuse?i thought the ratio for acids in the nitrating mixture was 1-1?
anyway, im off to try some experiments, cya
#8
Nick
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Posted 30 July 2003 - 02:09 PM
Oh no, normal handling will not cause NC to ignite, so it is quite safe to squash it between your fingers, but I think there's a good chance that trying to ram it into a rocket motor would, especially if it's highly nitrated. Sunlight won't cause it to go off either, although it will very slowly cause it to break down. As it breaks down, it releases oxides of nitrogen, and if it's in a confined space like a closed jar, these gases build up and speed up the decomposition even more. It isn't dangerous in small quantities, but it does gradually make the NC less effective. So store it in an open container.
NC in acetoe is a nitrocellulose lacquer. But commercial NC lacquer, for example the stuff that Skylighter sells as a binder, does not contain the right sort of NC for use as a propellant. Because cotton is a very long polymer, with many -OH groups which can be nitrated to -ONO2 groups, there is a practically infinite range of NC's, varying from almost 0% nitrogen up to about 14% nitrogen, which is the most powerful. What you get depends mainly on the strength of the acids, the ratio of the acids, and how long you let it react.
14% nitrogen NC is a high explosive and deflagrates very violently, IIRC (single base) smokeless powder contains roughly 12% nitrogen, then ping-pong balls and old cinema film contain even less, and so burn much more slowly.
I would say that yours is probably about right for a propellant. If using pure NC as a propellant, then all the oxygen for its combustion must be present in the molecule, so it needs to be quite highly nitrated. And the more nitrated it is, the more sensitive it is. But, you could use a less nitrated NC, which will be safer to use, and mix in a powdered oxidiser like potassium nitrate into the NC/acetone syrup before you make it into your rocket.
It will just deflagrate fast if ignited by a fuse in a paper tube. It is possible for the more nitrated NC's to go from deflagration to detonation if confined well enough and in large enough quantities, but it is unlikely that that will happen. But of course, a fast deflagration is enough to cause a violent explosion if your rocket goes wrong.
As you can see, even though NC is very easy to make, it is quite a complicated subject! You will need to do some experimentation with it before your rockets work well and are reliable and consistent.
NC in acetoe is a nitrocellulose lacquer. But commercial NC lacquer, for example the stuff that Skylighter sells as a binder, does not contain the right sort of NC for use as a propellant. Because cotton is a very long polymer, with many -OH groups which can be nitrated to -ONO2 groups, there is a practically infinite range of NC's, varying from almost 0% nitrogen up to about 14% nitrogen, which is the most powerful. What you get depends mainly on the strength of the acids, the ratio of the acids, and how long you let it react.
14% nitrogen NC is a high explosive and deflagrates very violently, IIRC (single base) smokeless powder contains roughly 12% nitrogen, then ping-pong balls and old cinema film contain even less, and so burn much more slowly.
I would say that yours is probably about right for a propellant. If using pure NC as a propellant, then all the oxygen for its combustion must be present in the molecule, so it needs to be quite highly nitrated. And the more nitrated it is, the more sensitive it is. But, you could use a less nitrated NC, which will be safer to use, and mix in a powdered oxidiser like potassium nitrate into the NC/acetone syrup before you make it into your rocket.
It will just deflagrate fast if ignited by a fuse in a paper tube. It is possible for the more nitrated NC's to go from deflagration to detonation if confined well enough and in large enough quantities, but it is unlikely that that will happen. But of course, a fast deflagration is enough to cause a violent explosion if your rocket goes wrong.
As you can see, even though NC is very easy to make, it is quite a complicated subject! You will need to do some experimentation with it before your rockets work well and are reliable and consistent.
#9
Pyromaster2003
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Posted 30 July 2003 - 02:40 PM
once again thank you very much for this information. i packed some NC lightly (you scared me when talking about it igniting when squashed) into a tube and made it into an m-80 style firecracker. the fuse lit and ignited the NC which then made a nice pop and popped the ends out. i then made an m-80 with flash powder and placed this ontop of a fairly large piece of NC to try and detonate it through shock. i couldnt tell weather it detonated or not, but it vanished(could of just deflagrated repidly). i have one more piece of NC left now so i made put it in the middle of a 5 inch squared piece of tin foil and place the NC in the centre then wrap it tightly around the NC (will look like them old ping pong ball smokers) and place this next to a tick walled firecracker containing flash powder, hopefully i will see from that weather it detonates or not.
when adding the 2 acids together i had the, unprofecianol, jam jar in an ice bath. when i was adding the nitric acid very very slowly i noticed white fumes comeing from the jar i then stopped and moved away until they stopped then carried on added the nitric acid. is it ok for me to keep adding the nitric acid when there are fumes evolving?Cheers Chris
when adding the 2 acids together i had the, unprofecianol, jam jar in an ice bath. when i was adding the nitric acid very very slowly i noticed white fumes comeing from the jar i then stopped and moved away until they stopped then carried on added the nitric acid. is it ok for me to keep adding the nitric acid when there are fumes evolving?Cheers Chris
#10
Nick
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Posted 30 July 2003 - 02:54 PM
70% nitric acid produces white fumes in moist air anyway, it is nothing to worry about. But it is a good idea to be careful when adding the sulphuric acid to the nitric, it can get very hot. The increase in temperature probably made it produce more fumes, but it is normal.
I am sure you won't detonate NC like that. It might be possible with some very good flash powder (like a 70/30, KClO4/very fine Mg), in a quite thin-walled tube, in the middle of some well pressed, highly nitrated NC with good confinement. But not with the NC in the open next to a thick walled flash-based charge. In order to detonate something you need a very sudden shock. With a thick walled flash charge, the walls of the charge have sufficient inertia that they accelerate relatively slowly, and this produces more of a push, rather than the sudden shock which is required. Also if the walls of the flash charge split open on the side opposite to the NC, then most of the energy is wasted in the wrong direction.
Ideally of course you would use a primary explosive to detonate it, but primary explosives are not something that you should make without some serious thought and a massive amout of reading and research before hand, because they will easily take off your hands. Good lab skills are also essential to make them safely.
But this is not the place to be discussing such things...
I am sure you won't detonate NC like that. It might be possible with some very good flash powder (like a 70/30, KClO4/very fine Mg), in a quite thin-walled tube, in the middle of some well pressed, highly nitrated NC with good confinement. But not with the NC in the open next to a thick walled flash-based charge. In order to detonate something you need a very sudden shock. With a thick walled flash charge, the walls of the charge have sufficient inertia that they accelerate relatively slowly, and this produces more of a push, rather than the sudden shock which is required. Also if the walls of the flash charge split open on the side opposite to the NC, then most of the energy is wasted in the wrong direction.
Ideally of course you would use a primary explosive to detonate it, but primary explosives are not something that you should make without some serious thought and a massive amout of reading and research before hand, because they will easily take off your hands. Good lab skills are also essential to make them safely.
But this is not the place to be discussing such things...
#11
Pyromaster2003
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Posted 30 July 2003 - 03:32 PM
ah once again i learn much. i used a pretty bad flash even though the Al was very fine (5 micron), i had to use sodium chlorate(from weedkiller im afraid) which isnt too pure.
anyway, i think i will make one more batch of NC and try a rocket. i will get some more acetone tomorow and try the rocket out. thanks for all your help;)
anyway, i think i will make one more batch of NC and try a rocket. i will get some more acetone tomorow and try the rocket out. thanks for all your help;)
#12
zanes
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Posted 30 July 2003 - 04:25 PM
errr.... actually cordite is usied for bullet propellant, and yes i do know what i am on about, i shoot .22 and 5.56mm SA 80 on target ranges and on exercises with blanks:bounce:Originally posted by smpip
Nitro-cellulose is used as a propellent for bullets, even if I did know the strengths of your acid/mix, I would tell you to leave alone.
[Edited on 30-7-2003 by zanes]
#13
Pyromaster2003
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Posted 30 July 2003 - 05:02 PM
i know that acetone is nail varnish remover but does anyone know how pure the acetone is as nail varnish remover?i went to a paint store and asked and she looked at me funny and said 'raw acetone?no love sorry:)'.i know they sell it in the chemist just down the road from me but i think its expensive and nail varnish remover would be less expensive for a bigger volume im guessing.
#14
smpip
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Posted 30 July 2003 - 05:24 PM
[quote][i]Originally posted by zanes
[/quote]
errr.... actually cordite is usied for bullet propellant, and yes i do know what i am on about, i shoot .22 and 5.56mm SA 80 on target ranges and on exercises with blanks:bounce:
[Edited on 30-7-2003 by zanes] [/quote]
Errr....actually Nitro-cellulose = Gun cotton = Cordite:duh:
[/quote]
errr.... actually cordite is usied for bullet propellant, and yes i do know what i am on about, i shoot .22 and 5.56mm SA 80 on target ranges and on exercises with blanks:bounce:
[Edited on 30-7-2003 by zanes] [/quote]
Errr....actually Nitro-cellulose = Gun cotton = Cordite:duh:
#15
smpip
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Posted 30 July 2003 - 05:41 PM
Originally posted by Nick
70% nitric acid produces white fumes in moist air anyway, it is nothing to worry about.
70% nitric acid, (white) fumes are nothing to worry about???(yeah right!).
Do you (Pyromaster) actually have any suitable breathing apparatus
While I am on this subject, the law is vague about having a few Ounce's of BP, but there is no uncertainty on where the law stands on NC production/possession, and as your (Nick) easy going advice does not make clear how easy it is to run into major trouble, with NC production, you don't even mention cascade nitration!!
I feel you have been negligent in the extreme:flames:
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