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Plasticizer problem

underground - 20-11-2015 at 12:37

From this topic it says that you can make a really good plasticizer from polybutene ( bird repellant) motor oil and methylricinoleate. I tried this method without success. I tried to plasticize 10gr of powdered sugar with no luck. I tried with 10% from Kitchen Improvised, 10% ( 1.83%PBN 6.19%MethRicin 2.06%SAE 30 MotorOil) 15% ( 2.75%PBN 9.28%MethRicin 3.09%SAE 30 MotorOil) and 15% (6.3%PBN 7.2%MethRicin 1.5%SAE 30 MotorOil) All of them was very brittle. The less brittle was the last one but steel far from what it must be.

I just want to make an ETN based C4 but i am using powdered sugar because i dont want to waste my ETN

[Edited on 20-11-2015 by underground]

OneEyedPyro - 20-11-2015 at 14:53

Powdered sugar isn't exactly going to work the same way as ETN would in a mixture, I have a feeling ETN would cling together better than the sugar.
I know semtex is about 20% inerts so you could try adding a bit more plasticizer/binder, 2% PIB, 3% MRO and 15% motor oil might work better.

I'm not sure how you're mixing the ingredients but dissolving a low weight conventional motor oil and PIB in a non polar solvent and kneading it into the ETN until homogenous then evaporating the solvent is a pretty good method.

NeonPulse - 20-11-2015 at 17:31

I agree, the inert testing is not really needed if you use a small amount say 5 g to start.measure carefully so not to have too much inert ingredients. It is quite easy. Just dissolve the plastics/oils in white spirit mix till homogeneous and evaporate solvent. All or most of the solvent must be evaporated before rolling the plastic out. Easy process really.

underground - 20-11-2015 at 22:32

I dissolve them in unleaded gasoline, mix the sugar and i let the gasoline to evaporate.

OneEyedPyro why so much Motor oil ? Every combination that i have seen usually uses more MRO
C4 has only 10% inerts. I want to keep the inerts low for better VoD

OneEyedPyro - 21-11-2015 at 00:34

I'm not really sure what role MRO would play in such a mixture to be honest, I doubt it would act much different than motor oil though. I've heard it prevents some solids in plastic explosives from recrystallizing and hardening but I wouldn't think that would be a big problem with ETN.

You can always add some NG to help make a nice handling product while keeping the VoD up, NG is very effective as a plasticizer and it helps as a binder since it dissolves some of the ETN making it tacky.
2% PIB, 8% NG and 5% oil would probably make a decent handling plastic with a good VoD, the ratios are purely speculation but it should be pretty close to a workable mixture.

underground - 21-11-2015 at 03:34

The problem with NG is that it is not storage stable.

greenlight - 21-11-2015 at 04:12

Nitroglycerin is sensitive because of its vapour pressure causing microscopic bubbles which form in it and act as initiating spots when shocked.
If it is absorbed into an absorbent material which I am sure PETN would suffice, it stops these bubbles from forming and would make a more stable product.
I don't know about longer term storage as I have seen a youtube video of a linear shaped charge using this explosive mixture and upon arrival at the detonation site, the charge is sweating/leaking some of the nitroglycerin out the side.
I am sure there is some chemical that can be used to stop the sweating of the NG though.

OneEyedPyro - 21-11-2015 at 05:01

When properly neutralized and purified NG is quite storage stable in the sense that it won't decompose after years if not decades.

The way it tends to separate from mixtures is a problem but since ETN is soluble in NG I don't think it would be such an issue.

NG has a bit worse of a reputation than it deserves in my opinion.
I remember the first time I did a hammer test on some NG and it took 5 solid hammer strikes to set it off, I was quite surprised sinse I was expecting peroxide like sensitivity.

In any case there are other very safe liquid energetics like nitromethane if you're not comfortable with NG.

nitro-genes - 21-11-2015 at 05:20

This may also be interesting, 1,2 propanediol is available as a less toxic anti-freeze:

US 3208890 A

Nitration to 1,2 PGDN is pretty straightforward, sensitivity comparable to TNT IIRC. Toxicity of the 1,2 PGDN is not really clear, presumably similar to NG and absorbed through skin.

greenlight - 21-11-2015 at 05:22

You are right NG does get almost a worse name than organic peroxides.
I have never done a hammer test on it but all the results that I have read from them are just like yours 4-5 hits compared to 1 or two for acetone peroxide.
I think it is less sensitive if a drop is placed on a hard surface and hit compared to if you soak it into a tissue and then smack it. I think ot takes less hits to initiate it then.

PHILOU Zrealone - 21-11-2015 at 16:03

Quote: Originally posted by underground

From this topic it says that you can make a really good plasticizer from polybutene ( bird repellant) motor oil and methylricinoleate. I tried this method without success. I tried to plasticize 10gr of powdered sugar with no luck. I tried with 10% from Kitchen Improvised, 10% ( 1.83%PBN 6.19%MethRicin 2.06%SAE 30 MotorOil) 15% ( 2.75%PBN 9.28%MethRicin 3.09%SAE 30 MotorOil) and 15% (6.3%PBN 7.2%MethRicin 1.5%SAE 30 MotorOil) All of them was very brittle. The less brittle was the last one but steel far from what it must be.

I just want to make an ETN based C4 but i am using powdered sugar because i dont want to waste my ETN

The process doesn't work wel because sugar is a highly polar compound (a lot of hydroxy alcohol groups and an aldehyd function; thus very soluble in water and hydrophile) while your Motor Oil,PBN and Me ricinoleate are highly apolar, alcanic and hydrophobic.
You are thus trying to mix like water and oil...it is harder!

ETN is kind of apolar, hydrophobic and as such in chemistry like likes like...so in that case the hydrophobic plasticizer mix do actually kind of dissolve in each other.
See chewing-gum and benzine example.

Beter watch at the octanol/water coefficient of compounds to get the feeling of good compatibility.

underground - 22-11-2015 at 09:35

I have tried with 15% inerts and 20g of ETN but still not big deal. I used 6.5%PBN 6.5%MRT and 0.2%MO. Any suggested combinations for PBN-MRT-MO ?

[Edited on 22-11-2015 by underground]

Praxichys - 23-11-2015 at 10:53

Quote: Originally posted by underground

I dissolve them in unleaded gasoline, mix the sugar and i let the gasoline to evaporate.

I think gasoline is a poor choice of solvent and may be causing some of your problems. Modern gas can be up to 10% ethanol, will contain various organometallic antiknock additives (like MMT), oxygenates (typically ketones or esters), detergents, metal deactivators, stabilizers, antioxidants, and a whole host of unsaturated hydrocarbons.

http://bcn.boulder.co.us/basin/waterworks/gasolinecomp.pdf

There are plenty of things in there that will polymerize with or crosslink the PBN and the methyl ricinoleate. Once the rest of the volatiles evaporate, you are left with something like a chunk of plastic with a lot of filler.

Try looking for highly hydrotreated paraffinic solvents like coleman camping fuel or barbeque charcoal lighter fluid. They will contain almost zero unsaturated or aromatic compounds and will not cause polymerization problems. You could also use a pure reagent-type solvent like n-heptane, hexanes, cyclohexane, etc.

[Edited on 23-11-2015 by Praxichys]

underground - 23-11-2015 at 12:01

Can i use just pure aceton for that purpose ?

[Edited on 23-11-2015 by underground]

Praxichys - 23-11-2015 at 12:35

That depends on what you're trying to achieve.

If you have already recrystallized your ETN into a dense crystalline state, ideally that should not be modified. To do it right, you need a solvent that dissolves only the plasticizers and binders and not the ETN. The ETN crystals are wet with a solution of the binders and plasticizers and the solvent dries, leaving unmodified, dense grains of ETN coated in a thin layer. RDX is handled this way in the manufacture of C-4.

Acetone will dissolve the ETN. When the mixture is dried, the crystal structure of the ETN will be modified. If these crystals too small or too fluffy, total density (and hence, performance) might suffer.

So, acetone will probably work. However, it is not the ideal situation for performance.

EDIT: Some suitable solvents -

Mineral spirits
Zippo fluid
Oil-based paint thinner
Coleman camp fuel or "white gas"
Barbecue lighter fluid
Petroleum ether
Xylenes
any isomers of hexane or heptane
VM&P Naphtha

Look on MSDSs for keywords like "Light hydrotreated paraffinic hydrocarbons" (With the exception of xylenes, all of these products are basically the same thing. They differ slightly in boiling point, so some will take longer to evaporate than others.)

[Edited on 23-11-2015 by Praxichys]

underground - 24-11-2015 at 01:37

So i guess white spirit (paint thinner) will do the job

underground - 5-12-2015 at 05:32

Can just ETN and vaseline make a good plastic explosive ?

NeonPulse - 5-12-2015 at 16:56

White gas/ Coleman fuel also used in dry cleaning. Zippo fluid works well the list that pray provided pretty much covers it. As fo ETN /petroleum jelly it may work but I suspect it would have rather poor handling and be hard to load properly plus susceptible to melt in Warner temperatures or even from over kneading. Another very real problem I experienced some time ago when I experimented with ETN and silicone grease was a serious nitro headache. This headache was a beast,very bad lasting all night and part of the next morning. So just be aware that ETN can cause this fi mishandled like I did when I was not very experienced in these matters.

underground - 5-12-2015 at 17:54

I always use gloves and i am trying not to come in contact with them. How can i check if polymerization is working ? Maybe it is working with gasoline. What if i try first to see how the material looks like after the evaporation of the solvent, without the addition of ETN ? Try first with gasoline and then with pure acetone to see if there is any difference between them in the end

[Edited on 6-12-2015 by underground]

PIB 19

Laboratory of Liptakov - 14-12-2015 at 13:03

When I see and read a big problem with plastification, I can recommended Poly Isomer Butylene from commerce vulcanize tape. Usually called PIB 19. Her molecular weight (long of molecule) is good. Respective her middle molecular long /weight. Long of molecule is a crucial conditions for purpose any PIB. Because PIB can be as oil to hard solid rubber. And allways is it only PIB. //Same difference pay for silicone oil and any synthetic glue - binder. For example rat or bird trap. // But with very different molecular weight. On Liptakov channel you can see good and easy plasticizer from tape (e-bay) this compose: PIB 4 -5 % (dissolved in heptane on 10% liq.) And synthetic oil 5W40 also same, 4-5% of all amount. Ration is possible change, usually 4:6 to 6:4. Best is 1:1, respective 4,5+4,5% of all ammount. Together thus 8 - 10% plastificator. Heptane (gasoline) evaporate, of course. I have not with plastification nothing problems. Watching video Chedditex. Dr. Liptakov

underground - 14-12-2015 at 13:15

What do you usually use ? Pib, MRO and motor oil?
So maybe i must use PIB and not polybutene

[Edited on 14-12-2015 by underground]

Determination

Laboratory of Liptakov - 14-12-2015 at 15:11

But I say, I write. Only PIB from tape and motor oil (syntehtic) 5W40. Its all. Tape is need dissolved in gasoline. Two day process. On 1g tape 10g heptane.
Determination of the concentration: 5,00 g of the solution poured onto a stainless steel surface. Evaporate heptane. Make a ball of pure PIB. Consider at 0.01 grams. If it is 0.45 g for 10g is it 0.9 g. In 10 g of the solution was 0.9 g PIB. The concentration of the solution is 9%. If you want to add 4.5 g PIB somewhere? Calculation: 100: 9 = 11.1. 4,5x11,1 = 49.95 = Thus, in 50 g solution is 4.5 g (dry) PIB. Into 50g poured 4,5g 5W40. Stirr. In this time we have 9grams of plastificator. For 91 grams of ETN, PETN, or AN,(Plastan) for KClO3, (Chedditex) or flour (building animals) or anything fine material. Dr. Liptakov

underground - 16-12-2015 at 13:27

Quote: Originally posted by Laboratory of Liptakov

I can recommended Poly Isomer Butylene from commerce vulcanize tape. Usually called PIB 19.

Is it the same with Self-amalgamating tape made out of PIB ? By cutting the tape and add it into heptane, then after 2 days filter it and let the heptane to evaporate will ppt out pure PIB ? Will this work ?

markx - 17-12-2015 at 02:22

Quote: Originally posted by underground

Quote: Originally posted by Laboratory of Liptakov

I can recommended Poly Isomer Butylene from commerce vulcanize tape. Usually called PIB 19.

Yes, the selfamalgamating/vulcanizing tape does contain PIB, but the amount is rather small and the tape is not cheap. Extracting the pib with heptane or other nonpolar hydrocarbons (regular gasoline works too) will do the trick and you do not need to let the solvent evaporate. Just determine the concentration of the solution (by weighing a sample before and after solvent evaporation) and dose accordingly into your formulation. In fact it is much easier to dose pib in solution as it is a terrible sticky mess when in pure form and trying to remove a chunk from it is quite a bit of work. The PIB from tape has quite a high mw polymer and will definately require the addition of a plasticiser.
Hence you may also look into rodent glues and bird repellants....they are mostly pure pib and sold in bulk quantities for "asocial" prices. The pib from these products usually has a lower mw and is more like a very sticky viscous liquid rather than a sticky solid. Therefore this product may not require any additional plasticisers and one can simplify the compositions even further.

Fulmen - 17-12-2015 at 04:26

Another approach is to precipitate the PIB with a more polar solvent like acetone. While it requires you to redissolve it when making plastic it's much easier to store in it's pure form.

underground - 17-12-2015 at 06:27

Markx i have already polybutene (not PIB) from bird repellant (read my above posts) but did not worked well

Fulmen - 17-12-2015 at 08:47

I haven't tried the bird repellant, but PIB from tape works fine in combination with oil even at 90% solids.

Laboratory of Liptakov - 17-12-2015 at 14:57

Underground you need this: http://www.ebay.co.uk/itm/Toolcraft-Poly-Isobutylene-PIB-Aut...
Is it tested, working, nothing problem. No cutting. Normal 2 meter to gasoline tape as snake. No filtration. Tape can be ( is it better), as one snake in gasoline. For all times. As dead worm. In long (30 days+) concentration increasing. PIB is pretty expensive, therefore is better let the snake in a glass. And concentration determine again. After a long time, it is possible to pull out the whole snake from the glass. Stretch between the fingers. Filtration is almost impossible. Dishes and destroyed everything around. All times tested. And 1:1 with oil, of course.
Liptakov.

VladimirLem - 26-12-2015 at 05:10

Quote: Originally posted by underground

Can just ETN and vaseline make a good plastic explosive ?

I think/hope so...

I think im going to try this (95%ETN, 5 vaseline)...its not some kind of plasic explosive, but should work pretty good to get a high density (but, with alots of tests before, casue shit is pretty sensitive) without that much work

However...anyone already did ETN/Vaseline?

underground - 26-12-2015 at 06:56

Vladimir if you are going to try this, please tell us the results

[Edited on 26-12-2015 by underground]

Sebacate impact : none ?!

pdb - 2-6-2016 at 08:24

After purchasing bis(2-ethylhexyl) sebacate, I started testing around 20 combinations, with the follwing protocol :
- PETN 85% in all recipes (when/if I find a satisfactory formula, I will increase PETN percentage point by point until it becomes non usable)
- 15% built by mixing 3 ingredients : Blu-Tack binder 8-15% + sebacate 0-5% + oil SAE 10W 0-5%

My findings so far :
- oil softens the plastic but makes it sticky to fingers (same as with vaseline). Difficult to get ride of when on your skin
- Blu-Tack binder yields a moldable product, while 3M self-amalgaming tape binder gives something hard and crumbly, which does not stick to itself
- I didn't see any difference with & without sebacate, which puzzles me.

I know lots have been discussed on this forum about platicizing PETN or RDX, but nothing definitive. I would be interested to hear from someone having experienced with sebacate.

Thanks.

plasticizer

Laboratory of Liptakov - 3-6-2016 at 01:55

You watching this: https://www.youtube.com/watch?v=-Brs1bqr_7M
Only 8% - 10% plastificator is possible used for all materials. ...LL... :cool:

Conditions are using tape and oil 5W40. Usually 1:1.

plasticizer

Laboratory of Liptakov - 24-7-2016 at 12:31

For this energetic material was used PETN a basically fraction 0,1 x 0,1 mm. Milled through sieve (0,1 ) as dry material. EM content (estimate) a very fine parts, 0,01 mm cca 10% from all. Content PIB from self-amalgamating tape 6%, synthetic motor oil 5W40 same, 6%. Plasticizer together 12%. Used watercolor - acrylate red and orange, mixed after plastification. Maybe 0,7 to 1,5 % in dry form. ...LL... :cool:

plasticizer

Laboratory of Liptakov - 5-1-2017 at 00:32

New link on basic preparation plastic material. https://www.youtube.com/watch?v=euVUa7C5rAM
........LL........ :cool:

greenlight - 5-1-2017 at 03:30

That looks great LL.!
I will have to try it as a replacement for using polybutene bird repellent as the binder as it takes hours of rolling and doesn't get to that plasticity.
Good work.

Laboratory of Liptakov - 7-1-2017 at 13:44

Well, this tape is I mean best. Has ideal molecule weight, respectively long of molecular chains is ideal for purpose as plastic binder. Bird repellent has short chains, (low molecular weight) therefore is difficult or impossible preparation good binder. Thanks for watching,.......LL........ :cool:

greenlight - 7-1-2017 at 20:39

Yes, the end product looks very good.
I cannot get the bird repellent PE to pull apart and stretch like that without breaking.

One question I have is what is the final density of your plasticized explosive?
Is it as high as you can get with bird repellent like 1.4-1.45.

plasticizer

Laboratory of Liptakov - 8-1-2017 at 03:10

Well. In video is not explosive, but only fine the flour. But with some material (1,77) can be in plastic consistence about 1,4. At handle pressing. With ratio 8% PIB + 4% oil, can be density 1,5g /cm3. However material will has low plasticity. But for filling shaped charge is better just using hard plastic. There can increase density on 1,6g /cm3. This method was measured. And confirmed 1,58g /cm3.......LL......... :cool:

greenlight - 8-1-2017 at 04:20

Thats sounds good as the plastic I am using at the moment is @ density 1.45 but using about 14% inert material.
I just ordered some of the same tape and I will give it a go with the next batch as you have convinced me.
Thanks LL....

[Edited on 8-1-2017 by greenlight]

PHILOU Zrealone - 8-1-2017 at 08:41

Quote: Originally posted by Laboratory of Liptakov

Well. In video is not explosive, but only fine the flour. But with some material (1,77) can be in plastic consistence about 1,4. At handle pressing. With ratio 8% PIB + 4% oil, can be density 1,5g /cm3. However material will has low plasticity. But for filling shaped charge is better just using hard plastic. There can increase density on 1,6g /cm3. This method was measured. And confirmed 1,58g /cm3.......LL......... :cool:

If I do the calculation right...
Density of PIB and oïl is 0,90 g/cm³; content 12%
Density of the explosive powder is 1,77 g/cm³; content 88%
so
Density of mix 12/88 = (0,90*12%)+(1,77*88%) = 1,6656 g/cm³
You write 1,4 --> Where does the 16% gap come from (1,4/1,6656 =0,8405)? Air?

Dornier 335A - 8-1-2017 at 13:39

Almost!
The density of the mixture is not the arithmetic mean, it's the harmonic mean. Which gives
1/(0.12/0.9+0.88/1.77) = 1.59 g/cm³.

It's still 12% air by volume though - it might be suboptimal grain geometry but I have a feeling it enters while you knead the plastic (just like when candy canes are made).

Laboratory of Liptakov - 9-1-2017 at 01:49

I know, seems it that is it all unusual, according arithmetic mean should by 1.66 g /cm3. However only in machine pressing in thick metal cavity. At normal use is all always worse. Therefore PETN 88/12 with density (in cavity shaped charge) 1,58 is very good result. And even it is almost precise, what describe Dornier. .....LL....... :cool:

PHILOU Zrealone - 9-1-2017 at 10:25

Quote: Originally posted by Dornier 335A

Almost!
The density of the mixture is not the arithmetic mean, it's the harmonic mean. Which gives
1/(0.12/0.9+0.88/1.77) = 1.59 g/cm³.

It's still 12% air by volume though - it might be suboptimal grain geometry but I have a feeling it enters while you knead the plastic (just like when candy canes are made).

Wow! I didn't knew this and was wrong for so much time.

Thank you Dornier 335A, I was really missing that information...especially if working onto detonic parameters what are strongly density dependant...

The bigger the density difference between A and B into a binary mix, the bigger the effect (lower bending of the harmonic mean vs the arithmetic one).

DubaiAmateurRocketry - 9-1-2017 at 10:38

Hmm, isnt the % of air also dependent on viscosity of the plasticizer/polymer?

Laboratory of Liptakov - 9-1-2017 at 13:57

Also I am thanks for Dornier. Harmonic mean.....1/(0.12/0.9+0.88/1.77) = 1.59 g/cm3.....is a new thing, information for my. Very interesting.......LL........ :cool:

Dornier 335A - 10-1-2017 at 05:49

To get an idea of how much the plasticizer hurts performance, I plotted calculated detonation velocity and pressure of a PETN/paraffin mix vs fraction paraffin:

Detonation velocity:

Detonation pressure:

greenlight - 10-1-2017 at 06:20

Nice, where did you get the data from?
I use a PETN PE at the moment with 14% binder/plasticizer and I calculated the detonation velocity to be around 7000 m/s which agrees with what you have on your VOD graph.

[Edited on 10-1-2017 by greenlight]

Fulmen - 10-1-2017 at 07:34

Interesting, but also misleading (I think). I assume you're using theoretical density here, and in reality that's very hard to accomplish.

PHILOU Zrealone - 10-1-2017 at 11:01

Do those graphs only take into account the density variation (for example playing with Kamelet's and the simple harmonic mean of densities of paraffin wax and PETN) or also the impact of the paraffin wax onto the oxygen balance and the overal energy output?

Can you share a little the calculations behind the plot/graph?

Funny to see that the attenuation becomes less with the increasing % wax --> at 40% must be close to 5 km/s and stil over 100 kbar...I wonder to see extrapolation up to 100% wax...theorically should be positive VOD and pressure by extrapolation... while practically of course should be 0...

Would be nice to turn your plot from .png to .jpg sothat your plot doesn't show at first preview like a black board (this dissappear if you click on it).

Bert - 10-1-2017 at 15:29

Having seen vacuum degassing used to eliminate or at least minimize bubbles and voids when casting composite rocket fuel grains, I wonder if anyone has tried adapting vacuum processing to plastic explosive manufacture?

Fulmen - 10-1-2017 at 15:50

Could be useful for loading charges, but probably not for the manufacture itself. Kneading it is bound to reintroduce air, so wouldn't any increase in density is lost unless you handle the product very deliberately with a minimum of reshaping?

Dornier 335A - 10-1-2017 at 15:51

The data was calculated with a rather simple (only 1000 lines of code...) program of mine. It guesses the reaction, calculates temperature and finally other detonation parameters using a few empirical equations. It has surprising accuracy, almost approaching that of expensive programs like EXPLO5. A complete JCZ3 implementation is on its way though...

Anyway, at 40% wax (OB = -146%) the VoD is calculated to 5450 m/s and P to 132 kbar at 1.28 g/cm³. More than that and the temperature starts to drop too low for my model.

DubaiAmateurRocketry - 11-1-2017 at 00:27

dornier you havent posted a video in a while

PHILOU Zrealone - 11-1-2017 at 09:52

Quote: Originally posted by Bert

Having seen vacuum degassing used to eliminate or at least minimize bubbles and voids when casting composite rocket fuel grains, I wonder if anyone has tried adapting vacuum processing to plastic explosive manufacture?

This would be indeed an effective way to reduce the air incorporation...but the all kneeding system must be under vaccuum.

Since following the perfect gas law: p*V=n*R*T
--> then reducing the pressure will proportionnally reduce the quantity of air incorporated.

If 10% air is incorporated into a normal process at ambiant pressure; then into identical conditions but the pressure, reducing the pressure by 2, 5 or 10 will reduce the air incorporation to 5%, 2% or 1% respectively (vs the initial 10%).

Theorically if pressure can be set to 0 mm Hg (or close because 0 is unreachable) then the air incorporation will be negligible.

Practically of course one has to work with non/least volatile HE, plasticizer and oils...considering the fact any solid has a vapour pressure...lowering the overal pressure will increase the apparent/relative volatility of all the ingredients: so even PETN or ETN may start to sublime from the kneeder compartiment to other unsuitable parts of the system and reduce the % of ingredients of the kneeded mass based on their respective vapour pressure.

PHILOU Zrealone - 11-1-2017 at 09:56

Quote: Originally posted by Dornier 335A

The data was calculated with a rather simple (only 1000 lines of code...) program of mine. It guesses the reaction, calculates temperature and finally other detonation parameters using a few empirical equations. It has surprising accuracy, almost approaching that of expensive programs like EXPLO5. A complete JCZ3 implementation is on its way though...

Anyway, at 40% wax (OB = -146%) the VoD is calculated to 5450 m/s and P to 132 kbar at 1.28 g/cm³. More than that and the temperature starts to drop too low for my model.

Nice program and project. Thank you for the calculation at 40% wax.

Sadly I don't have such programming abilities (although I understand the concept behind code lines and iterative calculations), so I work more on feeling, raw datas comparison and extrapolation from graphics.

But as I can see, I'm not too bad since it took me less than 1 minute to guestimate/extrapolate the VOD and pressure at 40% wax

I wish that one day you will do like Engager and let the forum benefit from your ingenious calculation program.

[Edited on 11-1-2017 by PHILOU Zrealone]

MineMan - 11-1-2017 at 10:03

Some nagging thoughts I have had for a while.

I don't know chemistry well enough to answer this, but is there any other plastizer options that can get the job done with only 1-3% inerts?

Or another option that I have confidence in, increase the grain size so less inerts are needed, like this...

https://www.walmart.com/ip/Educational-Insights-Play-Foam-Co...

MineMan - 11-1-2017 at 10:04

I have played with this product (children's toy) and the air gaps can be compressed quite well.

PHILOU Zrealone - 11-1-2017 at 10:35

Quote: Originally posted by MineMan

Some nagging thoughts I have had for a while.

I don't know chemistry well enough to answer this, but is there any other plastizer options that can get the job done with only 1-3% inerts?

Or another option that I have confidence in, increase the grain size so less inerts are needed, like this...

https://www.walmart.com/ip/Educational-Insights-Play-Foam-Co...

Everything is a matter of scale.
You may enter the field of nanomaterials if the film of plasticizer becomes too thin, it will loose part of its macroscopic properties (stretching ability, elastic ability or sticking ability) because to keep those you need to keep several molecular radius of like molecules.

You are right that increasing the particle size will reduce the surface of particle to coat with the plasticizer (active surface will be less) and thus the quantity of it...
but it may:
1°) become less kneedable (increased viscosity)
2°) become more breakable.
3°) become more sensitive because the weakest link remains the large crystals of HE (ETN, RDX and HMX for example)
--> To test.

Sole alternative would be to foccus on active binders/plasticizers...that are dense and contribute to the explosive properties.
--> Nitrocellulose and non volatile explosive gellifiers for example.
--> Other known technical compounds, glycidyl azide/ nitrate polymers, ...
--> Other unknown polymeric compounds (I have a lot of ideas because polymers usually induce higher densities and better stability (heat and shock) than monomers)

greenlight - 11-1-2017 at 10:42

I don't think its possible to get a moldable plastic explosive with <3% inerts. The lowest I have seen is C4 with 9% inerts.
All the new explosives testing seems to be focusing on PBX's which are bonded with a plastic polymer and have as little as 5% inerts.

Large grain size would be hard to obtain and they would probably get broken down in size a lot while incorporating the binder with rolling and kneading.
It looks like that playfoam is small rubber balls coated in some sort of binder that makes them stick to each other so I am guessing air gaps would be a problem.

MineMan - 11-1-2017 at 10:48

Philou,

To avoid the sensitivity problem I was going to form large grains from small crystals with smokeless powder and acetone. TACP if a perfect candidate because of the small crystals, low sensitivity and positive OB! The children's product is quite mold able, maybe I can dissolve that in acetone... but the foam might dissolve also...

Laboratory of Liptakov... this could be your claim to fame! I want to experiment with this but I can not find any PIB tape in the US...

And Dornier, I am legitimately jealous of you, remember me when you go places ...and when you are a chief engineer....

PHILOU Zrealone - 11-1-2017 at 12:53

Quote: Originally posted by MineMan

Philou,

To avoid the sensitivity problem I was going to form large grains from small crystals with smokeless powder and acetone. TACP if a perfect candidate because of the small crystals, low sensitivity and positive OB! The children's product is quite mold able, maybe I can dissolve that in acetone... but the foam might dissolve also...

Laboratory of Liptakov... this could be your claim to fame! I want to experiment with this but I can not find any PIB tape in the US...

Beware that the TACuP may be storage inadvisable into contact with smokeless powder and/or aceton.
TACuP is a complex of NH3 and as such the NH3 is held by the Cu(ClO4)2 but not at 100%...
so the NH3 may react:
1°) with the aceton to make aceton-imin and dark polymerisation tars (only if exposed for long)
2°) most of all, with the nitric esters to hydrolyse or amonolyse it...

The children product you referenced is said to be non-sticky. (At first I thought it was magnetic core, with rubber arround)
--> So i guess the coating is stiking to itself but not to other stuffs.
--> I wonder what it is

No PIB tape...
I'm sure bird repellent/rat glue should work just fine but you have to find the right process and order of addition of the ingredients...
--> When working at Procter&Gamble on silicon additive to allow for wrinkle resistance of clothes and easy post wash ironing...
We did make an aqueous 50% silicon solution from 80% silicon into ethanol (about 5000 cps)...allowing the 80% to fall into water resulted into immediate precipitation and hard (very viscous) plastic chewing-gum totally unworkable (>100000 cps); reversely when allowing the water to fall drop by drop into the 80% silicon ethanolic solution, despite a transitory moderate increase of viscosity (not unworkable at all 15000), we ended up with a very thin liquid only 10 centipoise (thus about 10 times as viscous as water) composed of sub-micron-sized silicon beads into a water-ethanol mix.

[Edited on 11-1-2017 by PHILOU Zrealone]

Herr Haber - 13-1-2017 at 10:01

No PIB tape #2

This is a question I've been asking myself everytime someone said that they cant find PIB:
Why dont you guys try to get it from somewhere else ?

Gloves first come to mind. You all have rubber gloves right?
And for those living in the land of the chewing gum and Ford you probably can find some chewing gum at your local convenience store.
Or go tear some tires to get at the bladder that holds the air.
Dont cut your gasmask to pieces though

It probably is as easy to get PIB from those sources as from bird/rat traps.
Am I failing to see something?

PHILOU Zrealone - 13-1-2017 at 11:29

Quote: Originally posted by Herr Haber

No PIB tape #2

This is a question I've been asking myself everytime someone said that they cant find PIB:
Why dont you guys try to get it from somewhere else ?

Gloves first come to mind. You all have rubber gloves right?
And for those living in the land of the chewing gum and Ford you probably can find some chewing gum at your local convenience store.
Or go tear some tires to get at the bladder that holds the air.
Dont cut your gasmask to pieces though

It probably is as easy to get PIB from those sources as from bird/rat traps.
Am I failing to see something?

Bird/Rat glue I have bought is only PIB (90-80%) and solvent like hexane (10-20% by weight) nothing else...for 2,5-3,5€/100 g into brico shop...you can't hardly make it easier to get.
The product is also immediately mixable as such with mineral oil or organic solvent.

I was also thinking to chewing-gum (after use/chewing so you get rid of most sugar, aroma) or to Multi-fix by Pritt/Henkel for Poster (glue/paste without solvent containing Polybuten but with a mineral charge).

Hennig Brand - 23-1-2017 at 20:37

I haven't done anything HE related in about a year probably, but,

I never accurately measured the crystal density of the solid HE used or the density of the polymer it was mixed with to form a plastic/putty type explosive. However, using the published data for densities of both and calculating an average density based on proportions used always came out to very, very, close to the product density found using good scales to determine mass and a decent graduated cylinder and careful volume measurement using the water displacement method.

From what I saw, more kneading generally resulted in a density closer to what the calculated average density was. I have not used the solvent method in a while. I settled on bird repellent (91% PB IIRC, I looked for the highest percentage I could find) and mineral oil. I use a bit of heat (a previously heated, with hot water to ca. 50C, then insulated to slow heat loss, rolling board, glass cutting board for instance) and a glass rolling pin (can be bought for baking, there are also really light (not glass) Teflon coated rolling pins that would likely work really well, or even just a suitable glass bottle).

If I had air in most of my putty explosives, when well kneaded, it was a very small amount (I think).

BTW, good to read some of what you characters are writing about and see what you are up to again.

I have actually been tied up lately applying some of my science & engineering skill to an R & D project where we are making synthetic diesel from wood.

[Edited on 24-1-2017 by Hennig Brand]

diesel from wood

Laboratory of Liptakov - 24-1-2017 at 06:35

Making synthetic diesel from wood is my dream for all life. ...... :cool:

MineMan - 24-1-2017 at 13:04

I thought the bird repellent was not that good because it is a short molecular chain as LL stated.

It is hard to beat the ease of NM and Nitrocellulose. Are there any agents that would slow down the NM evaporation? Petroleum jelly helps, but it seems a high amount is needed, which resulted in no detonation....

Laboratory of Liptakov - 24-1-2017 at 13:14

Camphor is pretty available, solid material and soluble in esters. Next is possibility use microtene bag.

PHILOU Zrealone - 24-1-2017 at 14:27

NM with NC is a bit like using MN (Methyl nitrate) with NC.
Better use EGDN or NG with ETN and NC instead.

Or the more exotic 1,2-dinitroethan ...denser, less volatile, but less available and harder to do.

Microtek - 25-1-2017 at 13:48

Concerning inert binder/plasticizer systems, and trouble with finding PIB:

I am presently conducting a series of experiments on a silicone (poly-dimethylsiloxane) system. It consists of curable silicone rubber caulking for construction (the kind you buy for DIY projects) and silicone oil (bought the same places for lubricating rubber seals and such, or at the pharmacy for lubricating... different things). It produces a mouldable product with superior mechanical properties at about 85 % inerts and seems quite forgiving of variations in the binder/plasticizer ratio (in a range around the 50/50 mark). 85 % active ingredients seems low, but bear in mind that silicone has a higher density than PIB/diester. If you compute the volume fraction of inerts, it is actually quite close to the value obtained for C4.
At present, I have only tried it with a non-energetic filler, in order to investigate the mechanical properties and behaviour after prolonged storage (I'm at the 2 month mark tomorrow, and so far there has been no change).

silicone plasticizer

Laboratory of Liptakov - 26-1-2017 at 00:18

Plasticizer on silicone based, poly-dimethylsiloxan oil + classic transparent silicone rubber. Results after 30 minute preparation. By 60 Celsius.

........

.........LL

Microtek - 27-1-2017 at 14:39

today I heated a sample of the inert plastique at 85 C for 3 hours to see if I could replicate your results. However, in my case, the sample did not exhibit any signs of change in the physical properties. The kind of transparent silicone rubber I used was neutral curing (no smell of vinegar), how about yours? Also, did you use any solvents in the preparation?

Uriel - 28-1-2017 at 14:12

Hello guys !
(it's my first message on this forum)
I've made research in plastic ETN.
- Motor Oil + ETN 25/75 it quitte good (23 or 24% are too few and 24 at 30 are perfect... but less powerfull of course)
- 9 Motor Oil + 1 Lecithine plastizer, about 17/18% with ETN give a plastic but that flows. Under it is powder, over it's flowing... (but good density).
- PIB/PB (rat glue and I don't know de proportions of each) 14/15% is quite good : there is my video here :
https://www.youtube.com/watch?v=s3K67Cqzm-I

- And about 11%PIB + 4% motor oil is such good and density is better !
- I've found that the PIB can be mix under water, so, I've put ETN/Water and PIB and it's quite easy to knead, it is the method of the real C4. I let drys many days. The density is a little better. (So better detonation pressure).
I'm pretty proud of myself on this development ;-)

For the moment, my conclusion is : if you haven't PIB you can use motor oil at about 25% (and less if you can use some Lecithine but the adhesion falls and the plastic can flow)
If you can have PIB : about 15% is a good compromise but the density is not perfect, because there are tiny air zones (but can be improved by adding oil, like 11%PIB + 4% oil).
I'll probably make a video of standard tests in the future.

[Edited on 28-1-2017 by Uriel]

plastic

Laboratory of Liptakov - 28-1-2017 at 15:32

Good attempt. Hardcore video. Your plate I estimate on 8 mm. But 30 grams a High Quality brizant plastic, should by making this:

And middle quality homemade should by making hole 10 mm.

Uriel - 19-3-2017 at 12:25

Hello guys !

I've made the tests !
My two plastic contains about 14% PIB by mass.
I wanted to compare ETN plastic with PETN plastic to have an idea.
As the ETN cristals are biggers, the density of ETN is quite lowest.
As ETN cristals had a density of 1.827 (1.6 is for liquid) against 1.77 for PETN, I was hoping to reach better density, but no.
I've reach a density of 1.32 for ETN and 1.36 for PETN (37mm high and 35.5/36mm for PETN)

30g in both charge with plasticizer additional.

As you can guess, the first one, the weakest, is ETN ans the most brisant is PETN.
Both are in the same tube of paper of exactly 30mm internal.
(And the steel plate is 10x40mm of section).

[Edited on 19-3-2017 by Uriel]