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underground
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What is PLF ?
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Laboratory of Liptakov
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Plasticizer, plastificator, PLF, my personal acronym, sorry....
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PHILOU Zrealone
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Quote: Originally posted by greenlight  | Just a quick question regarding oxygen balance.
My last batch of PE was made just using PETN as the energetic. I know that a perfect oxygen balance improves the explosives detonation properties.
PETN is slightly underoxidized (-10%) and ETN is overoxidized slightly @ 5.2-5.3%.
Would a plastic explosive from a ratio of PETN to ETN that has been calculated to 0% be more powerful than the straight PETN plastic explosive or
would the binder and plasticizer throw out the balance during detonation.
[Edited on 10-2-2016 by greenlight] |
Because PETN and ETN have very close density (most active parameter in CHON EM brisance):
1°)then the use of ETN will be better for plastic explosive vs PETN since its unused oxygen will burn the plasticizer/binder fuel somehow providing a
better/higher energy output...this will compensate the dilluting effect of the binder!
2°)Using an OB balanced mix of PETN/ETN will also be beneficial over PETN, but must be less interesting than pure ETN plastic.
3°)Using an active binder and PETN will outperform PETN plastic because the energy output will be higher. ETN plastic would be even better!
4°)Using an OB improved active binder (like NC) will be even better (ideally the denser active binder the best).
5°)Using both OB improved active binder and OB mix will be the summum. Ideally 0% OB binder and EM mix.
[Edited on 11-2-2016 by PHILOU Zrealone]
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)
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greenlight
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Thanks for the replies everyone, it seems that most plastic explosives like C4 and semtex will end up having a negative oxygen balance in the end.
Would an ETN PE versus a PETN PE come a draw in the end because the PETN plastic would have a slightly higher detonation velocity to counteract the
negative OB% or is ETN still superior?
The only use for an atomic bomb is to keep somebody else from using one.
George Wald
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Hennig Brand
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From Meyer:
"
Brisance
Brisanz
The performance of an explosive cannot be expressed by means of a single characteristic parameter. Brisance is the destructive fragmentation effect of
a charge on its immediate vicinity. The relevant parameters are the detonation rate and the loading density (compactness) of the explosive, as well as
the gas yield and the heat of explosion. The higher the loading density of the explosive (molding or pressing density), the higher its volume specific
performance; also, the faster the reaction rate, the stronger the impact effect of the detonation. Moreover, an increase in density is accompanied by
an increase in the detonation rate of the explosive, while the shock wave pressure in the detonation front (Detonation) varies with the square of the
detonation rate. Thus it is very important to have the loading density as high as possible.
This is particulary true for Shaped Charges.
Kast introduced the concept of “brisance value”, which is the product of loading density, specific energy and detonation rate.
Brisance tests are upsetting tests according to Kast and Heß; the compression of a copper cylinder is determined by actuating a piston instrument;
alternatively, a free-standing lead cylinder is compressed by the application of a definite cylindrical load of the explosive being tested: Upsetting
Tests.
"
ETN:
Specific Energy = 1091 kJ/kg
Detonation Velocity = 8000 m/s
Density = 1.6 g/cc (obtainable loading density?)
PETN:
Specific Energy = 1205 kJ/kg
Detonation Velocity = 8400 m/s
Density = 1.7 g/cc (obtainable loading density?)
Brisance Value = Loading Density * Specific Energy * Detonation Rate
Brisance ValueETN = 1600 kg/m^3 * 1091 kJ/kg * 8000 m/s
Brisance ValueETN = ca. 14 billion
Brisance ValuePETN = 1700 kg/m^3 * 1205 kJ/kg * 8400 m/s
Brisance ValuePETN = ca. 17 billion
Relative Brisance Value PETN / ETN = 17 / 14 = ca. 1.21
I may have underrated ETN in terms of density, but PETN still comes out significantly ahead in terms of brisance even with more optimistic numbers for
ETN.
Note: Aluminum is added to PBXs and putties(plastic explosives) sometimes, but not in shaped charge applications, from what I understand, or other
applications where brisance is much more important than energy output and a long drawn out impulse. Most applications that use these types of
explosives require a high brisance shattering action. Simply because of the distance between atoms, the relatively poor mixing and the energy
requirements of the reactions (probably other reasons) the secondary oxidation reactions are much slower and add to blast effect, but are not very
helpful to brisance as I understand it. Particles of high explosive are embedded in a binder/plastic matrix (not well mixed at all in comparison to a
molecule of high explosive!).
[Edited on 14-2-2016 by Hennig Brand]
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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PHILOU Zrealone
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| Quote: Originally posted by Hennig Brand | From Meyer:
"
Brisance
Brisanz
The performance of an explosive cannot be expressed by means of a single characteristic parameter. Brisance is the destructive fragmentation effect of
a charge on its immediate vicinity. The relevant parameters are the detonation rate and the loading density (compactness) of the explosive, as well as
the gas yield and the heat of explosion. The higher the loading density of the explosive (molding or pressing density), the higher its volume specific
performance; also, the faster the reaction rate, the stronger the impact effect of the detonation. Moreover, an increase in density is accompanied by
an increase in the detonation rate of the explosive, while the shock wave pressure in the detonation front (Detonation) varies with the square of the
detonation rate. Thus it is very important to have the loading density as high as possible.
This is particulary true for Shaped Charges.
Kast introduced the concept of “brisance value”, which is the product of loading density, specific energy and detonation rate.
Brisance tests are upsetting tests according to Kast and Heß; the compression of a copper cylinder is determined by actuating a piston instrument;
alternatively, a free-standing lead cylinder is compressed by the application of a definite cylindrical load of the explosive being tested: Upsetting
Tests.
"
ETN:
Specific Energy = 1091 kJ/kg
Detonation Velocity = 8000 m/s
Density = 1.6 g/cc (obtainable loading density?)
PETN:
Specific Energy = 1205 kJ/kg
Detonation Velocity = 8400 m/s
Density = 1.7 g/cc (obtainable loading density?)
Brisance Value = Loading Density * Specific Energy * Detonation Rate
Brisance ValueETN = 1600 kg/m^3 * 1091 kJ/kg * 8000 m/s
Brisance ValueETN = ca. 14 billion
Brisance ValuePETN = 1700 kg/m^3 * 1205 kJ/kg * 8400 m/s
Brisance ValuePETN = ca. 17 billion
Relative Brisance Value PETN / ETN = 17 / 14 = ca. 1.21
I may have underrated ETN in terms of density, but PETN still comes out significantly ahead in terms of brisance even with more optimistic numbers for
ETN.
Note: Aluminum is added to PBXs and putties(plastic explosives) sometimes, but not in shaped charge applications, from what I understand, or other
applications where brisance is much more important than energy output and a long drawn out impulse. Most applications that use these types of
explosives require a high brisance shattering action. Simply because of the distance between atoms, the relatively poor mixing and the energy
requirements of the reactions (probably other reasons) the secondary oxidation reactions are much slower and add to blast effect, but are not very
helpful to brisance as I understand it. Particles of high explosive are embedded in a binder/plastic matrix (not well mixed at all in comparison to a
molecule of high explosive!).
[Edited on 14-2-2016 by Hennig Brand] |
I have made a comparison of various (poly)nitrate esters(*) from Josef Köhler and Rudolf Meyer (JK&RM) and other datas sources by plotting VOD vs
density; the resulting diagram is kind of bi-linear (one slope for the liquid nitrate esters, and another one for the solid nitrate esters) but there
is a problem with ETN; first I thought it to be due to the fact it might be into the median zone yielding properties between liquid NG and solid MHN
but it is not that, the value of 1.6gr/cm³ is obviously wrong...ETN has a density much closer to 1.72 gr/cm³.
If you take a deep look into the book "Explosives" by JK&RM; there are a lot of typos and discrepencies  .
If you correct that value of 1.6 into 1.72 then everything comes to normal in the graphic truly linear dependance.
I will try to find that graph back and post it here.
I will also try to make the detonic calculations for various ETN/PETN mixes and ETN/Binder vs PETN/Binder following JK&RM thermodynamic
calculation instructions.(and post those here).
(*)
Liquids:
Methyl nitrate
Ethyl nitrate
EGDN
NG
Butyl glycol dinitrate
Butyl glycol trinitrate
NIBTN (nitroisobutyl trinitrate)
Solids:
Polyvinyl nitrate
Nitrocellulose
ETN
MHN (Mannitol hexanitrate)
PETN
TMDNETN (TetraMethylol-DinitroEthane-Tetranitrate)
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)
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nitro-genes
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My guess would be that the positive oxygenbalance of ETN aids only very little to an increase in VoD, (and thus brisance) compared to PETN. The
density of the charge as a whole is affected more by the density of the HE used. Also, the binder and etn are physically seperated, meaning only a
small percentage of the binder will react in the reactionzone itself and actually aid to the increase in VoD. , 99% of the inerts that actually do
combust, will combust from detonation products and or oxygen from the air long after the detonation wave has passed, increasing total energy output,
but decreasing brisance.
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PHILOU Zrealone
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If this was true, then brisance of TeNM would'nt be so dramatically increased by organic aromatic fuels...wich only decrease the overal density...
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)
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Hennig Brand
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OK, I would say you are correct and the crystal density of ETN is probably closer to 1.72 g/cc (I have references that state this as well). However,
even if ETN and PETN are given equal densities and detonation velocities the higher specific energy value for PETN will give PETN a higher brisance
value by about 10%.
TeNM, I have not worked with. I believe this is the chemical formula, C(NO2)4 (Tetranitromethane). TeNM isn't even an explosive in its pure form, it
is an oxidizer. It makes sense that adding a liquid fuel to a liquid oxidizer, in the correct proportions, could make an explosive mixture. If they
are miscible, which I imagine they are, the molecules of oxidizer and fuel would be about as well mixed as they could possibly be, unless they were
part of the same molecule I suppose. Going from a non explosive oxidizer with a high density to an explosive with a lower density would increase the
brisance. Even going from an oxidizer fuel mixture with a very high positive oxygen balance to a more balanced mixture would result in a much faster
reaction--->(closer proximity of oxidizer molecules and fuel molecules, more even distribution of fuel and oxidizer and a higher energy density), (
more energy, more gas output)---> more specific energy.......even with a drop in density in this case. This is a special case, not very much
related to plastic explosives (I think).
[Edited on 14-2-2016 by Hennig Brand]
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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nitro-genes
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As two liquids it would be a different story indeed. What is interesting also is that different crystaI lattice structures for the same HE can affect
sensitivities. IIRC correctly, this is f.e. true for beta hmx. I've always assumed this was due to the orientation and distance of the functional
groups relative to each other, or due to physical properties from alterations in how the stimulus is transfered.
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PHILOU Zrealone
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| Quote: Originally posted by Hennig Brand | OK, I would say you are correct and the crystal density of ETN is probably closer to 1.72 g/cc (I have references that state this as well). However,
even if ETN and PETN are given equal densities and detonation velocities the higher specific energy value for PETN will give PETN a higher brisance
value by about 10%.
TeNM, I have not worked with. I believe this is the chemical formula, C(NO2)4 (Tetranitromethane). TeNM isn't even an explosive in its pure form, it
is an oxidizer. It makes sense that adding a liquid fuel to a liquid oxidizer, in the correct proportions, could make an explosive mixture. If they
are miscible, which I imagine they are, the molecules of oxidizer and fuel would be about as well mixed as they could possibly be, unless they were
part of the same molecule I suppose. Going from a non explosive oxidizer with a high density to an explosive with a lower density would increase the
brisance. Even going from an oxidizer fuel mixture with a very high positive oxygen balance to a more balanced mixture would result in a much faster
reaction--->(closer proximity of oxidizer molecules and fuel molecules, more even distribution of fuel and oxidizer and a higher energy density), (
more energy, more gas output)---> more specific energy.......even with a drop in density in this case. This is a special case, not very much
related to plastic explosives (I think).
[Edited on 14-2-2016 by Hennig Brand] |
I'm not comparing pure ETN vs pure PETN...but an optimized OB mix of the two with binder or a mix of each with a binder/plasticizer...
You should read the chapter about "Thermodynamic calculation of Decomposition Reactions" in Explosives by J.Köhler and R.Meyer (about 25 pages
included thermodynamic tables); they give step by step example, then you see that the central carbon atom into the PETN may be burnt during detonation
proces by the extra oxygen from ETN ...thus the energy output from the OB ETN/PETN mix will be increased by kg of explosive.
I will do the calculation and graph to make it clearer to you.
The mix binder and EM if kneeded enough becomes like a solid solution of EM into the binder...there is close/intimate contact between molecules.
The use of binary liquid (oxydiser/fuel) that are soluble into each other makes the mix 100% homogenous, but with solids and binder (viscous solids)
it is about the same even if not 100% homogenous on a molecular level.
*NH4NO3 prills and liquid/solid DNT wax/oil do detonate at higher speed and with more brisance than each compound appart.
*NH4ClO4/Triamino-Trinitrobenzene (binary solid mix) detonate at a much higher speed than each ingredient appart (+/- 9500 m/s) and the brisance is
increased aswel.
*Tetranitromethane is an explosive on its own! (see Explosives book by J.K and R.M)
Specific energy: 687 kJ/kg
Energy of formation: +263.7 kJ/kg
Heat of explosion: 2259 kJ/kg
Volume of detonation gases: 685 l/kg
density: 1.677 g/ccm
VOD: 6360 m/s at 1.637 g/ccm
When mixed with DNT oil, the mix goes into the VOD regio 9000-9500m/s with extreme brisance.
*Hexanitroethane is also an explosive on its own! (see Explosives book by J.K and R.M)
Specific energy: 854 kJ/kg
Energy of formation: +473.2 kJ/kg
Heat of explosion: 3102 kJ/kg
Volume of detonation gases: 672 l/kg
density: 1.85 g/ccm
VOD: 4950 m/s at 0.91 g/ccm
VOD extrapolated at max density: 6800 m/s
When the solid is mixed with DNT oil, the mix should reach the 10000 m/s milestone with extreme brisance.
This shows that over-oxygenated EM and under-oxygenated EM suffer from the same problem...dead weight of unreacted detonation products (oxygen in the
first case and carbon/fuel in the second one)...once this is circumvented by a binary (or more) system more oxygen balanced (that doesn't reduce too
much the overal density); then the full volumic/weight power is reached.
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)
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Hennig Brand
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I think we both have made some good points. I don't think everything either of us has said is completely correct, or at least not all of the time.
I'll have a look at that chapter, since a review couldn't hurt, but I think I still remember the fundamentals. I am not trying to pretend that the
extra oxygen doesn't provide for more energy through combustion type reactions, I so far am unconvinced though that it does much to improve the
brisance of the very brisant, ideal , molecular explosives. It is about the intensity of the impact (brisance), not total energy output. As far as
plastic explosives having very well mixed HE component(s) and binder this is normally not the case at all, at least not relative to a molecule of
ideal HE. The classic comparison is black powder and something like nitroglycerin or TNT. Even when extremely great lengths are taken to mill black
powder (KNO3, S, Charcoal mixture) it is still an extremely coarse crude mixture in comparison to a molecule of nitroglycerin or TNT for example, with
correspondingly inferior HE qualities. Another example is flash powder, even with extremely finely milled oxidizer and fuel components, still nothing
in comparison to one of the better molecular explosives even though the energy output is huge. In comparison to a molecule, the particles of HE in the
binder matrix of a plastic explosive are normally huge, from what I understand, and the binder layers have large average thickness as well and only
contact the HE at the boundary layer surrounding the particles of HE. It is the proximity/closeness of fuel atoms and oxygen atoms to one another and
nitrogen atoms to other nitrogen atoms, etc, and in good proportions, that makes an extremely fast reaction rate, high velocity, high brisance, HE.
Many of the more crude things done to unideal explosives, such as AN, to improve performance, would often do very little or even often take away from
an ideal, molecular, explosive if highest brisance is what is desired. When NG is added to AN, are we improving the AN or making worse the NG? An even
better example might be mixtures of AN and the oxygen deficient TNT (I think I would use pure TNT in shaped charges). Depends on perspective maybe. I
know there are many examples where there is a synergistic effect, greater sensitivity, more energy output, more gas output, etc, kind of enhancements
especially with AN mixtures and some others, but these are normally unideal explosives and it is normally the more ideal, molecular, type explosives
that are used in plastic explosives.
Hard to improve on (near) perfection!
I know that the HE component of a lot of mixtures often has the most control over the overall reaction rate (detonation velocity), often mostly due to
its being the largest proportion, but the speed and brisance are still normally lower than for the pure molecular HE (I think).
Depending on how they were mixed a PETN and ETN mixture might get decent enhancement from the extra oxidation reactions, I don't know to what extent
or under what circumstances exactly.
[Edited on 15-2-2016 by Hennig Brand]
"A risk-free world is a very dull world, one from which we are apt to learn little of consequence." -Geerat Vermeij
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Laboratory of Liptakov
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KMnO4
Next short question: Has somebody experience with KMnO4 as explosive? As main oxidizer? I think not deflagration mixture. Nothing glycerine or
sulphuric acid + permanganate. My reason is relatively (some week) stabile and non-hygroscopic mixture with VoD 2000m/s and more. I looking for on
google, world patents, in S-mad in similarly thread. No place nothing (interesting) .Thanks, LL.....
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Sulaiman
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From experiments during my youth,
oxidiser + fuel mixtures behaviour is dependant upon the intimacy of mixing,
results that I remember;
KMnO4 + Mg coarse particles = POOF !
KMnO4 + Mg fine particles = BANG !
NaClO3 fine grains each coated with yellow P = CRACK !
The last one had such brisance that I think it was a detonation rather than deflagration.
sorry, no hard data.
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wg48
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| Quote: Originally posted by Sulaiman | From experiments during my youth,
oxidiser + fuel mixtures behaviour is dependant upon the intimacy of mixing,
results that I remember;
KMnO4 + Mg coarse particles = POOF !
KMnO4 + Mg fine particles = BANG !
NaClO3 fine grains each coated with yellow P = CRACK !
The last one had such brisance that I think it was a detonation rather than deflagration.
sorry, no hard data.
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I remember the last one from my youth too.
Put a coin on a sheet of aluminium.
Place a pile of NaClO3 or the K salt to cover the coin.
Drop P4 desolved in CS2 on to the pile to saturate it.
Wait for the SC2 to evaporate (not too long)
Tap with a long very long stick .... bang
Examine impression of coin on the aluminium.
Certainly a rapid conflagration if not a detonation
I saw it demonstrated on the TV (UK) around 1967. Back then you could order a kilo of white phosphorus from B&H Chemicals and pick it up a few
days later no problem.
I do not suggest anyone try it LOL
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TheIdeanator
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How sensitive are the polyol nitrates, metal acetylides, and mixes like flash powder? Would I be able to transport them in a car to a site about 10
hours away or might I be better off preparing them on-site? I also plan on experimenting with shaped charges.
I've never made any EMs before and I want to do some amateur mining this summer.
“I will show you fear in a handful of dust.”
― T.S. Eliot
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Bert
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| Quote: Originally posted by TheIdeanator | How sensitive are the polyol nitrates, metal acetylides, and mixes like flash powder? Would I be able to transport them in a car to a site about 10
hours away or might I be better off preparing them on-site? I also plan on experimenting with shaped charges.
I've never made any EMs before and I want to do some amateur mining this summer. |
Start reading. All the information you requested is here.
In consideration of the other motorists and out of respect for any public safety personnel tasked with prying your sorry ass out of your wrecked and
possibly burning vehicle, please do not transport primary and/or secondary explosives in said un-placarded, non commercially inspected vehicle being
operated by a non hazmat licensed and non CDL driver.
Yes, you PROBABLY could get away with it. But no sensible person who knows enough to understand the exposure to those around you will sympathize with
you doing such a thing. Risk your own life if you must, please leave random others OUT of the situation.
Rapopart’s Rules for critical commentary:
1. Attempt to re-express your target’s position so clearly, vividly and fairly that your target says: “Thanks, I wish I’d thought of putting it
that way.”
2. List any points of agreement (especially if they are not matters of general or widespread agreement).
3. Mention anything you have learned from your target.
4. Only then are you permitted to say so much as a word of rebuttal or criticism.
Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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TheIdeanator
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| Quote: Originally posted by Bert | | In consideration of the other motorists and out of respect for any public safety personnel tasked with prying your sorry ass out of your wrecked and
possibly burning vehicle |
That is something I had not taken into consideration, thank you. My risk tolerance is pretty high but I definitely don't want anyone else getting hurt
if and when I make a mistake.
After reading through "Statistical study of rock drilling by hypervelocity jets from explosive shaped charges" by John William Brown(a good resource
if you want to blow holes in rock), it seems that shaped charges won't work as effectively as I'd like them to. The resulting holes are too small,
only about 0.2 times the charge diameter. Since I wanted to limit my shots to a maximum of an inch wide with a minimum of explosive and have holes
bigger than 3/16" it kills that idea and pretty much eliminates my incentive for HEs. Back to blackpowder and hard work.
This is my research phase for this project. Since I don't have the right power tools and want to avoid spending much on this I'm considering creative
options.
“I will show you fear in a handful of dust.”
― T.S. Eliot
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nitro-genes
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Quote Philou:
" *NH4NO3 prills and liquid/solid DNT wax/oil do detonate at higher speed and with more brisance than each compound appart.
*NH4ClO4/Triamino-Trinitrobenzene (binary solid mix) detonate at a much higher speed than each ingredient appart (+/- 9500 m/s) and the brisance is
increased aswel."
Curious though at what percentage of DNT the highest VoD will be achieved for AN/DNT though. My guess would be that at close to 3-4%, actually close
to ANFO (inert fuel). Although the fact that DNT itself is explosive (contributing to the detonation wave itself) may also contribute, as well as that
for AN mixtures detonable density increases with sensitizing fuels, and thus VoD. The easy at which both fuel and oxidizer seperately decompose
(activation energy) and total energry release also matter probably.
The VoD figure for AP/TATB is really incredibly high, amazing it can detonate at max density apparently, is there sensitation due to some
amineperchlorates formed?. If a mixture of TNT and AP would be reasonably stable and show similar sensitivity/VoD at max density, why do these kind of
composition seem to find little use?
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Dornier 335A
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The optimal ratio between DNT and AN in terms of VoD and detonation pressure will surely be a function of the particle sizes. With large AN crystals
in a DNT matrix, the highest VoD is likely to be achieved with very little AN. This is because rather than being an explosive (AN) mixed with an inert
fuel (DNT), it should be viewed as an explosive (DNT) mixed with an inert oxidizer - there is simply not enough time for the more slowly detonating AN
crystals to oxidize unburned carbon from the DNT before the shock wave has long since passed. With very finely powdered components, or porous AN
prills soaked with DNT, or fine AN powder mixed with or even partially dissolved in molten DNT (is that possible?), it's another story. The mixture
should behave much more like an ideal explosive, i.e. the reaction has reached equilibrium at the CJ point. Such a mixture would indeed have its
highest VoD when it is close to oxygen balanced.
The AP/TATB mixture's performance seems overestimated to me. It could be a theoretical value for a completely homogeneous mix at maximum density. Two
non-ideal explosives mixed on a macroscopic level should not reach such velocities, and certainly not at the max density. HNE/Tetryl (again two
solids, but both being ideal explosives) has been confirmed to be exceptionally brisant by a Sciencemadness member though. Its theoretical detonation
performance is similar to that of HMX, but with much higher energy output.
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PHILOU Zrealone
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| Quote: Originally posted by nitro-genes | Quote Philou:
" *NH4NO3 prills and liquid/solid DNT wax/oil do detonate at higher speed and with more brisance than each compound appart.
*NH4ClO4/Triamino-Trinitrobenzene (binary solid mix) detonate at a much higher speed than each ingredient appart (+/- 9500 m/s) and the brisance is
increased aswel."
Curious though at what percentage of DNT the highest VoD will be achieved for AN/DNT though. My guess would be that at close to 3-4%, actually close
to ANFO (inert fuel). Although the fact that DNT itself is explosive (contributing to the detonation wave itself) may also contribute, as well as that
for AN mixtures detonable density increases with sensitizing fuels, and thus VoD. The easy at which both fuel and oxidizer seperately decompose
(activation energy) and total energry release also matter probably.
The VoD figure for AP/TATB is really incredibly high, amazing it can detonate at max density apparently, is there sensitation due to some
amineperchlorates formed?. If a mixture of TNT and AP would be reasonably stable and show similar sensitivity/VoD at max density, why do these kind of
composition seem to find little use? |
AN and AP are very good oxydisers in such mixes...indeed at max density by opposition with conventional ANFO (VODmax between 3.5 and 4.5 km/s) where
air needs to be incorporated into the mix in a way to sensitize (during detonation compression wave, the air voids induces adiabatic compression
bubbles --> hot spots) but this reduces density and thus VOD.
Here we are talking about a ANFO with an active fuel like AN-NM that can detonate at max density.
But AN-NitroMethane (VOD between 4-6 km/s depending on NM%) suffer from the weak density of nitromethane (1.14 g/cm³), its lack of fuel to burn (fast
turns into overoxygenated mix).
In the case of DNT oils that display a density of +/- 1.54 g/cm³ you already gain a lot on density vs NM, the VOD is of course less than TNT (= 6.9
km/s) because less dense and worst OB (--> in the range of 6,2 km/s (but close to NM)).
In the case of DNT thus the fuel is burned by the excess OB of the AN contributing to the energy output...theorically the 0% OB mix seems to be wanted
but this needs to be verified by calculations.
This kind of mixes were used for cost reasons because DNT is cheaper to obtain than TNT and AN is a lot cheaper.
In the case of TNT/AN mixes "Amatols" they display lower brisance (80%) and VOD than plain TNT but much more total energy output for
underground/mining and underwater applications...
TNT/AP mixes will be expensiver and probably more sensitive (to impact, heat, bullet) ...two factors very important for military use.
About such mixes...the idea to incorporate hydrazinium or hydroxylaminium nitrate,perchlorate or nitroformiate will kick the VOD and brisance up,
since:
*N2H5NO3 has a VOD of 8.9 km/s
*N2H5ClO4 has a VOD of >7.5 km/s
*N2H5C(NO2)3 has a VOD of ??? probably over 7.5 km/s
*HONH3NO3 has a VOD of 8.0 km/s
*HONH3ClO4 has a VOD of ??? probably over 7.0 km/s
*HONH3C(NO2)3 has a VOD of ??? probably over 7.0 km/s
And this is way over those of NH4NO3 and NH4ClO4...
[Edited on 20-2-2016 by PHILOU Zrealone]
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)
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Sulaiman
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| Quote: Originally posted by wg48 | | Quote: Originally posted by Sulaiman | From experiments during my youth,
oxidiser + fuel mixtures behaviour is dependant upon the intimacy of mixing,
results that I remember;
KMnO4 + Mg coarse particles = POOF !
KMnO4 + Mg fine particles = BANG !
NaClO3 fine grains each coated with yellow P = CRACK !
The last one had such brisance that I think it was a detonation rather than deflagration.
sorry, no hard data.
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I remember the last one from my youth too.
Put a coin on a sheet of aluminium.
Place a pile of NaClO3 or the K salt to cover the coin.
Drop P4 desolved in CS2 on to the pile to saturate it.
Wait for the SC2 to evaporate (not too long)
Tap with a long very long stick .... bang
Examine impression of coin on the aluminium.
Certainly a rapid conflagration if not a detonation
I saw it demonstrated on the TV (UK) around 1967. Back then you could order a kilo of white phosphorus from B&H Chemicals and pick it up a few
days later no problem.
I do not suggest anyone try it LOL
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When I did the P + NaClO3 (together with a friend at my parents house, my father's garage was also my 'Lab')
one heaped teaspoon of NaClO3 on a metal milk bottle top (UK 'sterilized' milk bottle, c2cm dia.?)
on a 1" thick concrete slab, completely unconfined.
The book said that it would explode once the CS2 evaporated,
we waited, and waited, .... nothing.
must be yet another failure, back into the garage for more experiments.
15 or 30 minutes later a very loud CRACK ! like nearby lightning,
we dashed outside to find the concrete slab cracked and not much else visible.
We never tried that one again !
I don't know where deflagration ends and detonation begins, other than what I've read,
but it seemed similar to silver acetalide (Disilver ethyndiide)
Maybe P + NaClO3 with CS2 is equivalent to damp black powder / too much F in ANFO etc.?
EDIT: just removed an erroneous remark, hopefully before anyone read it!
[Edited on 20-2-2016 by Sulaiman]
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Deathunter88
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How can a chemical be above 100% pure? I have quite a few reagent bottles that state a purity upper value greater than 100%.
For example, my bottle of copper nitrate states a purity of 99-102% and my bottle of manganese dioxide states a purity of 98-101%.
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PHILOU Zrealone
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| Quote: Originally posted by Deathunter88 | How can a chemical be above 100% pure? I have quite a few reagent bottles that state a purity upper value greater than 100%.
For example, my bottle of copper nitrate states a purity of 99-102% and my bottle of manganese dioxide states a purity of 98-101%.
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Maybe the container is made somehow of the material thus giving you more for your money   ...
No! Just kidding!
Of course purity is at max 100% at least in our old physical world  .
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)
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Sulaiman
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Today I had my first go at nitrating cotton wool,
c5g cotton wool given a 2 hour soak in 20 ml 69% HNO3 with 50 ml 96% H2SO4 (drain cleaner),
rinsed in water, NaHCO3, water, NaHCO3, water, water, water,
now open air drying overnight.
1) Is there a simple titration (or other method) that I can do to estimate the level of nitration ?
2) also, would I be correct in thinking that if I ignite a sample and there is no carbon residue then it is probably fully nitrated ?
3) last but not least, I read a few a articles and watched several youtube videos before I started,
Is it COMPLETELY SAFE to squeeze out liquids from the nitrocellulose in my hand between rinses, like in so many videos ?
(being unsure I did not, in fact I was a little scared during the whole procedure)
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