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Microtek
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Reality check: Thousands of everyday items contain plasticizers from that subset. They are being phased out now (at least in the EU), but they have
been in use for decades, and millions of people have been exposed to them every day of their lives without taking exceptional amounts of damage.
The dangers of handling energetic materials in the first place, as well as dealing with the nitrogen oxides are far more serious concerns IMO.
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PHILOU Zrealone
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Quote: Originally posted by Microtek ![](images/xpblue/lastpost.gif) | Reality check: Thousands of everyday items contain plasticizers from that subset. They are being phased out now (at least in the EU), but they have
been in use for decades, and millions of people have been exposed to them every day of their lives without taking exceptional amounts of damage.
The dangers of handling energetic materials in the first place, as well as dealing with the nitrogen oxides are far more serious concerns IMO.
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The problem with Endocrinian Disruptors is that:
1) even minute amounts for short exposure time (a few days) may have severe consequences
2) the effect is not observable immediately onto the exposed subject... but wel once it tries to get childrens/offsprings... or that the offsprings
try to multiply...
3) effect is not only onto fertility but also onto brain development
4) here the dosis doesn't make the poison because they mimic hormones... it has an effect or the complete reverse effect depending onto the
exposure/concentration and this last may be effective at extremely low concentrations...
5) additivity of various ED as a daily cocktail is completely unpredictable... industrials are playing with the future of mankind and intellect... but
also with the future of many animals living into the surrounding...
Through the products we are exposed via cosmetics, plastic tools, plastics containers/cans in contact with food/beverages, food, pesticides, biocides,
nanoparticles... everyone of us is exposed to more than 30 to 100 various ED each day...some of those are persistant/remanent and bio-accumulate...
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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Rocinante
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Interesting paper about the sensitivity of ETN, melt cast ETN and its perfromance comapred to PETN, mercury fulminate and RDX.
http://www.wydawnictwa.ipo.waw.pl/cejem/vol_14_No_2_Early_Vi...
8027 m/s at their maximum density (1,7), impact sensitivity comparable to PETN in both cases (crystals, melt cast) and friction sensitivity about
twice as high as PETN.
What would be the precise detonation pressure? 300 kbar?
[Edited on 25-11-2017 by Rocinante]
[Edited on 25-11-2017 by Rocinante]
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greenlight
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When I calculate the detonation pressure (cj pressure) for PETN with the figures you state I get:
Pcj = (1.7)(8.03)²/4 = 27.404 GPa.
When converted to kilobar, I get 273.9.
Pretty close![:)](./images/smilies/smile.gif)
The calculation is not 100% exact though and can be out by 1% or so.
Be good, otherwise be good at it
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Dornier 335A
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That formula underestimates the detonation pressure for many explosives. The exact version is
P = ρ D2/(γ+1)
Where γ usually varies between 2.5 and 3.1. For ETN at 1.7 g/cc, gamma is about 2.7 which gives a detonation pressure of 305 kbar.
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greenlight
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I didn't know that I read the equation is only out by a small amount.
I accidentally put 8.03 instead of 8.3 as well for VOD.
What is y for PETN then?
Using 2.7 as y +1, you get 31.65 GPa or 316.5 kbar for PETN .
This sounds closer.
[Edited on 27-11-2017 by greenlight]
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Rocinante
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Has anyone tried someting more powerful than RDX? I assume that even RDX/ETN can reach ~ 320 kbar and most HMX/binder explosives reach to only about
350 - 360 kbar.
Their report states that RDX is 4× less friction sensitive than ETN recrystalized from EtOH, which is crazy. ETN is only 5× less friction sensitive
than MF.
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greenlight
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RDX is about 350 kilobar @ density 1.80.
HMX around 390 kilobar @ density 1.89.
The next explosive I think would replace HMX would be HNIW if it was not for synthesis cost problems among other things.
Approximate CJ pressure would be about 527 kilobar @ density 2.44 and massive VOD of 9.38 km/s.
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Rocinante
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I'm thinking about real world mixtures, not crystal densities. HNIW is about 400 kbar, but it is a dead thing due to PETN-like sensitivity and no
fielded, practical co-crystals. I'm thinking about amateur mixtures, like.. has anyone tried keto-RDX/some nitrofurazane//melt cast ETN?
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Dornier 335A
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Even at crystal density (2.04 g/cc), HNIW only reaches about 420 kbar compared to 393 kbar for HMX at crystal density. The effect of switching to HNIW
would therefore not be very significant considering the increased amount of inert material required to keep the sensitivity down.
I think I have seen RDX/ETN melt cast on youtube but it should be said that while it performs significantly better than Composition B it doesn't
perform better than pure RDX. I get 8590 m/s and 337 kbar at 1.75 g/cc for a 50/50 mixture.
RDX has a very high detonation velocity for its density, so most mixtures perform worse. The only exceptions are mixtures with strong oxidizers like
hexanitroethane or bis(2-difluoramino-2,2-dinitroethyl)nitroamine and those are out of reach for most amateurs.
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greenlight
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I see I was wrong with theoretical pressure for HNIW.
I thought it would be higher than just 420 kbar because of it having such high energy and the highest density out of most of the newer HE's.
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Rocinante
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Pressed RDX with 5 % of inerts does something like 310 kbar (some sources claim as low as 280 kbar and I'm aware how hard is to determine the pressure
even with exp. methods), if I'm not mistaken, so the 50:50 mixture should be slightly more powerful.
[Edited on 28-11-2017 by Rocinante]
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joseph6355
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It has been awhile... I have learned so much since the creation of this topic. I'm revisiting it now to discuss more about ETN.
I've been using trinitrophenol as a main charge for demolishing concrete structures, but the TNP proved to be toxic and dangerous.
My detonators were made using 7.92 mm (ED) and 6.35 mm (ID) stainless steel tubing that had one end closed by welding it. It was then added an amount
of 1000 mg of ETN and pressed with the help of a jig in the vice. On top of it was placed an amount of 250 mg of DDNP and slightly pressed again, and
finally on top of the DDNP, 200 mg of black powder was packed loosely with a wooden stick. A 6.35 mm in diameter piece of paper with a hole in the
middle was placed on top of the black powder and a fuse inserted through the paper and into the black powder. All of it was then sealed and firmly
held in place by filling the steel cavity to the top with hot glue.
The detonator seemed reliable on detonating cast TNP without the need of a bigger booster charge. It wasn't that difficult as some users reported here
on SM.
I'm mentioning this because I wanted to say that I'm somewhat familiar with the synthesis of ETN by the addition of erythritol in mixed acids.
ETN seems like a good EM to replace TNP, but it has a higher sensitivity, so desensitizing it is a must for safe handling.
Unfortunately I don't own a press strong enough to press high diameter charges. I have always cast my explosives, so I didn't bother to look for one.
I have some questions I was hoping that someone would help me, specially because I'm scared of casting ETN
Is it possible to achieve high densities with ETN by only phlegmatizing it with 10% petroleum jelly?
My TNP charges were cast within a PET plastic tube (50 mm dia) and I had to cut the tubes with a sharp knife to extract the solid. TNP didn't stick to
the walls but it stained it yellow. How easy would it be to remove the ETN block from this tube? Does ETN contract or expand upon cooling? Can I use
steel or copper tubes to cast ETN if the solid is easily removable?
Plasticizers are very hard to find where I live currently. The only one I was able to find was Dibutyl phthalate. Is plasticizing ETN possible with
DBP? What binders would be required?
I'm also trying to avoid plasticizers since they are endocrine disruptors.
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NeonPulse
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Ideally you should avoid casting ETN into metal tubing for safety reasons. Especially Aluminium. Some testing conducted by users here had found that
ETN can reliably detonate in contact with Al under certain circumstances under heating. Generally plastic is the way to go and ETN cast in it should
remove fairly easily. It does contract a little and shrinks on cooling. I think if you were to phlegmatise it this can be done using Polyisobutene or
polyisobutelene as a binder and motor oil to soften it some. If you can access methanol and castor oil you can easily make safer plasticiser from it.
Methyl ricinoleate is an excellent plasticiser in combination with PIB and if used in 8-10% you can easily press a nice high density charge. It is
very easy to make via transesterficaton the same way bio diesel is made.
Using it in amounts of 12% or so can give you a very nice easily mouldable plastic explosive. This takes some work but the results are well worth the
effort. You can attain density of 1.6g/cm3 plus if done right. This is great for an amateur job.
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joseph6355
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Quote: Originally posted by NeonPulse ![](images/xpblue/lastpost.gif) | Ideally you should avoid casting ETN into metal tubing for safety reasons. Especially Aluminium. Some testing conducted by users here had found that
ETN can reliably detonate in contact with Al under certain circumstances under heating. Generally plastic is the way to go and ETN cast in it should
remove fairly easily. It does contract a little and shrinks on cooling. I think if you were to phlegmatise it this can be done using Polyisobutene or
polyisobutelene as a binder and motor oil to soften it some. If you can access methanol and castor oil you can easily make safer plasticiser from it.
Methyl ricinoleate is an excellent plasticiser in combination with PIB and if used in 8-10% you can easily press a nice high density charge. It is
very easy to make via transesterficaton the same way bio diesel is made.
Using it in amounts of 12% or so can give you a very nice easily mouldable plastic explosive. This takes some work but the results are well worth the
effort. You can attain density of 1.6g/cm3 plus if done right. This is great for an amateur job. |
Does ETN attack metals and sensitizes itself when in contact with them?
I don't have access to polyisobutene or polyisobutelene unfortunately. Are there any other binders that I could use with methyl ricinoleate?
And indeed, methyl ricinoleate seems like a safe alternative to DBP.
Thank you.
EDIT
Can I use silicon rubber as a binder?
What should a look for when choosing different brand and types of silicon rubbers?
[Edited on 7/5/18 by joseph6355]
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Bert
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You are thinking of using the silicone sealing compounds used in construction for sealing windows, doors and around fixtures in bathrooms to replace
PIB or PB in a plastic explosive mixture?
These silicone sealers cure by reacting with water vapor, the commonly available ones release acetic acid while curing. Although they can be loaded
with solids before they cure, you would end up with a permanently shaped, rubbery but solid "chunk", not a soft re mouldable putty capable of being
formed to whatever shape is needed at a later time.
I have seen silicone sealers such as GE Silicone II used to make propellant grains and fireworks stars, while these sealers could be used for
fabricating flexible sheet explosives intended to be cut but not otherwise reconfigured after curing, they are not suited to making something like
Semtex or C4.
Rapopart’s Rules for critical commentary:
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3. Mention anything you have learned from your target.
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Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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joseph6355
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Quote: Originally posted by Bert ![](images/xpblue/lastpost.gif) | You are thinking of using the silicone sealing compounds used in construction for sealing windows, doors and around fixtures in bathrooms to replace
PIB or PB in a plastic explosive mixture?
These silicone sealers cure by reacting with water vapor, the commonly available ones release acetic acid while curing. Although they can be loaded
with solids before they cure, you would end up with a permanently shaped, rubbery but solid "chunk", not a soft re mouldable putty capable of being
formed to whatever shape is needed at a later time.
I have seen silicone sealers such as GE Silicone II used to make propellant grains and fireworks stars, while these sealers could be used for
fabricating flexible sheet explosives intended to be cut but not otherwise reconfigured after curing, they are not suited to making something like
Semtex or C4. |
Thats disappointing.
The product I mentioned is used for making these molds for casting, and also for cooking.
https://www.youtube.com/watch?v=JyQmEG9qmfw
Is there anything besides PIB that I could use?
The silicon rubber idea came from the PBX article on wikipedia.
[Edited on 7/5/18 by joseph6355]
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MineMan
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Petroleum Jelly works well. 10percent is a good value. This will provide all the desensitization you need.
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joseph6355
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I have found a commercial product that might provide me with PIB. Its a caulk PIB-based sealant.
The datasheet provides CAS numbers as well as the concentrations.
[SUBSTANCE][CAS NUMBER][CONCENTRATION]
Synthetic Rubber (Isobutylene-Isoprene copolymer)/ 9010-85-9 / 5 to 20
Castor Oil / 8001-79-4 / 1 to 10
Naphthenic Oil / 67254-74-4 / 10 to 20
Dolomite / 16389-88-1 / 20 to 30
Talc / 14807-96-6 / 25 to 45
Polyisobutene / 9003-29-6 / 15 to 25
Carbon Black / 1333-86-4 / 0,3 to 1,0
Titanium Dioxide / 13463-67-7 / 0,5 to 2,0
Organic and Inorganic Pigments / 147-14-8 / 0,5 to 2,0
I have also found another one that contains PIB, natural rubber, dolomite, talc, castor oil, mineral oil and petroleum jelly.
Is it possible to extract the binder with solvents?
I will look myself to see if other substances could also dissolve in the solvent, if so, the solvent could be brought to its boiling temperature and
slowly evaporated.
The problem is that I don't know if the substances would react with each other and render impossible the extraction of the binder.
Has someone attempted this yet with caulk sealants/adhesives? I hope so.
[Edited on 8/5/18 by joseph6355]
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Bert
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Could you provide a product name/number?
Rubber cement thinner is generally capable of dissolving rubber.
Attachment: Solvent-and-Thinner_Bestine.pdf (75kB) This file has been downloaded 425 times
[Edited on 5-8-2018 by Bert]
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
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3. Mention anything you have learned from your target.
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Anatol Rapoport was a Russian-born American mathematical psychologist (1911-2007).
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joseph6355
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Quote: Originally posted by Bert ![](images/xpblue/lastpost.gif) | Could you provide a product name/number?
Rubber cement thinner is generally capable of dissolving rubber.
[Edited on 5-8-2018 by Bert] |
It isn't found in the US or Europe.
I'm trying to find a thinner that contains n-heptane but so far no luck. I'll keep
looking for it.
Thanks Bert.
Is xylene capable of dissolving PIB?
Honestly I don't know if this method would extract anything. I'm quite frustrated.
[Edited on 9/5/18 by joseph6355]
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roXefeller
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It might extract it if you find a suitable solvent. But will the molecular weight of the extracted PIB be what you are hoping for? Dr Liptakov did a
couple videos comparing PIB from different sources and showed the European tape SCAPA to perform better, I presume it had a higher molecular weight.
This stuff isn't crosslinked though, like the isobutylene isoprene rubber. PIB needs the isoprene doping to provide crosslinking sites. It has the
resilient nature of uncured rubber which can be mixed, warmed, extruded, or injected for the purpose of crosslinking into a final shape.
As for silicone, if you are comparing the ETN to cast TNP, the PBX with silicone will setup firm like the TNP. Keep in mind PBX aren't in general
remoldable, rather solid charges pressed to shape. Waxy EM like TNT or TNP can be pressed without such binders but other material won't be
dimensionally stable wit out the added intergranular cohesion.
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joseph6355
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Quote: Originally posted by roXefeller ![](images/xpblue/lastpost.gif) | It might extract it if you find a suitable solvent. But will the molecular weight of the extracted PIB be what you are hoping for? Dr Liptakov did a
couple videos comparing PIB from different sources and showed the European tape SCAPA to perform better, I presume it had a higher molecular weight.
This stuff isn't crosslinked though, like the isobutylene isoprene rubber. PIB needs the isoprene doping to provide crosslinking sites. It has the
resilient nature of uncured rubber which can be mixed, warmed, extruded, or injected for the purpose of crosslinking into a final shape.
As for silicone, if you are comparing the ETN to cast TNP, the PBX with silicone will setup firm like the TNP. Keep in mind PBX aren't in general
remoldable, rather solid charges pressed to shape. Waxy EM like TNT or TNP can be pressed without such binders but other material won't be
dimensionally stable wit out the added intergranular cohesion. |
I think I'll give up the idea of plasticizing anything. I can't find PIB neither any product that contains it and allows its extraction.
The only alternative to achieve high density for me is to cast it, which I'm kind of scared of doing.
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Bert
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Quote: |
I'm trying to find a thinner that contains n-heptane but so far no luck.
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Quote: |
I can't find PIB neither any product that contains it and allows its extraction.
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You live in a country without gasoline, Colman camping fuel or any glue board type sticky traps.
Sounds like a nice place, no air pollution or vermin.
[Edited on 5-10-2018 by Bert]
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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Fulmen
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Nonsense, I'm sure you can find PIB somewhere. Self-vulcanizing tape should be available, I got a very nice product from it. I don't remember which
solvent I used, but I'm fairly sure it was an aromatic. Xylene should work. Just don't shake or stir the tape too much, the PIB will leech out of the
tape leaving a soft, black rubbery mass. Breaking it up only causes it to disperse in the thick PIB-solution, and it's not something you can filter
easily. So just let it stand for a few days and decant, the PIB can be precipitated out by adding acetone.
We're not banging rocks together here. We know how to put a man back together.
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