Sciencemadness Discussion Board

Best way for getting high density ?

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Hennig Brand - 26-8-2014 at 06:40

Yes, if PIB is used (especially high MW PIB) then I think a solvent is pretty much a necessity to achieve even mixing and coating of the solid explosive particles. Regarding oil types used, in many cases there is a big difference in the vapor pressures of the different oils available. Oil with a lower vapor pressure will evaporate more slowly, meaning the plastique won't dry out as quickly. Also I imagine relative solubility, especially with regards to temperature change, of the solid explosive in the various oils is important; recrystallization of the solid explosive and the resultant hardening of the plastiques could be faster or slower depending on the oil used I would imagine (I haven't really done any testing though). There are also viscosity differences to consider, especially with regards to temperature change. There are most likely a few other things I haven't thought of as well.

Dent Plate

Laboratory of Liptakov - 29-10-2014 at 13:43

Henning, perfect work. Good idea to use double steel. But this method is very inaccurate. Yes, I know it was just a fun experiment. It is perhaps a pity. You have the opportunity to get aluminum? The picture is a method that is used professionally. It is very simple. His name is dent plate. Lead, copper and steel are not suitable metals.
You have 2 holes in steel. Where is the rest energy? This is very inaccurate. Dent plate is an exact method. Into aluminum discharged all the energy. The depth of impact corresponds to the velocity of detonation.
LL



dent plate.jpg - 82kB

[Edited on 30-10-2014 by Laboratory of Liptakov]

VoD

Laboratory of Liptakov - 30-10-2014 at 01:38

Other experiences include:

VoD.jpg - 31kB

Hennig Brand - 30-10-2014 at 06:27

Yes, I do normally have access to aluminum. I tend to use as targets anything that is lying around, so the targets are usually less than perfect. Thanks for the good explanation.

I think all of those other metals have been used at one time or another as witnesses in various tests however. It wasn't a very accurate test I performed, but a lot could be known about the relative detonation velocities based on the size of the holes and how clean the holes were (amount of tearing and how much the steel was dented).

I like that last picture you posted, with the steel witness plate. Tells a lot about the detonation velocity of the 10% NG dynamite type explosive I tested in the detcord thread. According to the literature I reviewed weeks ago, those types of explosives do have very low detonation velocities (2000-3000m/s), which is consistent with your diagram.


[Edited on 30-10-2014 by Hennig Brand]

VoD

Laboratory of Liptakov - 30-10-2014 at 10:34

I'm glad that the pictures helped. Images are simple. As the graph and guidance for VoD calculation is inaccurate. However, if it agrees with your experience, that's good. Here in this picture is a different situation. Only 4 grams of high explosive 6500m/s and 7500 m/s. Steel plate 3mm. Interesting. Diameter expl. of 15mm. Hole of 15mm. Initiation No.10.
LL

6 a 7.jpg - 73kB

Hennig Brand - 30-10-2014 at 11:25

That is interesting; very different results. Much cleaner hole in the higher velocity shot. It gives me something to compare to which is nice. It looks like that ETN putty explosive I have been playing with has higher detonation velocity than I thought it had (when properly initiated).

VoD

Laboratory of Liptakov - 30-10-2014 at 13:42

According shaped charges (octopus? Pyramid?) I think that: 1 about 6700 m/s and 2 about 7500 to 7900 m/s. The charge has a weak edge. It is difficult to determine. The cylinder is much easier to determine.
LL

holes.jpg - 80kB

Hennig Brand - 31-10-2014 at 01:33

I had a cone shape or truncated cone shape in the back of my mind, but when forming it quickly by hand I think I fell a little short of the correct geometry. ;)
To get the shape formed correctly a mold or form of some kind would have worked better. If the velocities are really that high, I am very impressed.

Bert - 3-11-2014 at 08:06

Regarding "dent plate method":

Aluminum comes in a variety of alloys and hardness, T-0 to T-7 hardness is commonly available here...

What alloy/hardness would you choose for that 40mm plate/10gram charge you diagram?

I take it a plate of sufficient thickness not to "bulge" on back side is desired? From your practical experience, how thick might that need to be for some typical materials, weight of charge & charge diameters-

test

Laboratory of Liptakov - 3-11-2014 at 09:16

For 10 g charge with minimum 40 mm thick. Another important thing: Height = 3x diameter cartridges. For relevant results. That is the minimum. Hardness Aluminium 3 to 4 Medium. The bulge on the other side is not important. (see. fig.) The hardness of the aluminum is not too important. Important are the same test conditions. For the known detonation velocity (pressure) and an unknown detonation velocity / pressure.

micro.jpg - 121kB

Hennig Brand - 4-11-2014 at 00:31

Thanks, I will give that a try the next time I do a test.

methyl ricinoleate

Laboratory of Liptakov - 23-11-2014 at 12:42

I want to return to the topic of high density. Henning has a great knowledge of plasticizers. I read the entire thread. I see that the polybutylene is better than polyisobutylene. A little bit better? Or much better? Another question: How to make methyl ricinoleates? I know that it's almost like adipate and sebacate. It is important, in fact necessary ingredient in plasticizer.
He could make anyone of you methyl ricinoleate? I have methanol, castor oil, KOH and NaOH. Thank you, LL

Hennig Brand - 23-11-2014 at 14:24

Thanks for the compliment, but I am still just getting the basics about a lot of this stuff. It is better and worse. The product I have is very easily incorporated into a plastic/putty explosive without the use of a solvent, which saves a lot of work. This strength is also a weakness; it doesn't hold the explosive particles together as well as a higher molecular weight/longer average chain length polymer/binder. In order to compensate more binder is used and then it does make a decent plastique if done right. I don't think there is a one size fits all; the binder and plasticizer choice depend on the handling properties one wants in a plastic explosive.

Metacelsus - 23-11-2014 at 14:30

Making methyl esters of fatty acids is commonly done by people making biodiesel from vegetable oil. Castor oil is mostly the triglyceride ester of ricinoleic acid, so you can use base-catalyzed transesterification. Look on biodiesel sites for more details.

Here's a paper about castor oil biodiesel: http://www.icrepq.com/full-paper-icrep/222-barajas.pdf

[Edited on 23-11-2014 by Cheddite Cheese]

NeonPulse - 23-11-2014 at 16:29

I have made methyl ricinoleate and it works far better than oil alone. And polybutene seems to work better than pib.it seems less brittle and easily worked back to softness upon sitting for a while.having never used adipates or sebecates I can't comment on which is better but the ricinoleate is pretty darn good and easy to make. Its a quite simple reaction really.

roXefeller - 23-11-2014 at 17:57

It is straight forward, like making soap. In fact I made soap once doing this because of bad temperature control. I've attached the article I followed (they were experimenting with conditions and catalyst concentration). One thing I found helpful was to have all reagents at the reaction temperature before combining. After allowing time to react, stir in water to separate the glycerol and byproducts from the ester.

Attachment: methylricinoleate.pdf (42kB)
This file has been downloaded 280 times


Hennig Brand - 23-11-2014 at 19:39

Methyl ricinoleate does work and most importantly it is available to the hobbyist. Seems to me that methyl ricinoleate is not in favor, as a plasticizer, for most commercial applications however. I would have to go do a little digging, but IIRC it had much poorer storage stability than the ones typically used commercially.

methylricinoleate

Laboratory of Liptakov - 24-11-2014 at 03:11

roXfeller, thank you for pdf .. I suggest the following: 250 ml ricin oil + 65 ml methanol + 2.4 g KOH. Keep temperature at 70C for 90 minutes. Yield: 95 ml methylricinoleate + 42 ml glycerol. We can only try. LL

scheme.jpg - 22kB

markx - 24-11-2014 at 06:52

For the transesterification of (castor) oil, one important element is to keep the content of catalyst (KOH or NaOH) to a rather minimum amount (at least not exceeding the amount suggested in the synthesis description). Higher concentrations of the base tend to favour saponification reactions. Especially if the alcohol is not of fully anhydrous composition.

NeonPulse - 24-11-2014 at 16:21

The gelatinous mess was the result of my 1st attempt. And it was due to too much catalyst as well as poor temp control. Future reactions were much more successful with the right product yielded.

markx - 25-11-2014 at 05:22

For the comparison of PIB and polybutylene binders...I find that if a classical plastique type of product is desired then HMW PIB does give a better result in terms of consistancy and the mass really holds together very well. But it does require a fair amount of plastisizer (methyl riccinoleate e.g) to be reasonably moldable. If less is added the mass becomes quite tough and rubbery. Polybutylene on the other hand yields a softer stickier product which crumbles quite easily, but is near too perfect for phlegmatisation of SC loads in the 5%-10% inerts range. I've used 5% of polybutylene+5% methyl riccinoleate on PETN and RDX based SC loads and it gives excellent loading properties....good density and uniformity without excessive pressing. And just enough adhesion to form a solid charge that grips the casing and liner very well.

[Edited on 25-11-2014 by markx]

plasticizer

Laboratory of Liptakov - 25-11-2014 at 08:23


Interesting post markx. To refresh your memory. C4:
RDX ................................................. .. 91.0%
Di (2-ethylhexyl) sebacat ........................ 5.3%
Polyisobutylene ....................................... 2.1%
oil (synthetic 5W?) .................................. 1.6%.
This is not many (9%) of a plasticizer. Usually (often) it is 15%. Q: Is it possible to replace Di (2-ethylhexyl) sebacat, methyl ricinoleate? If yes. Also use the 5.3%? I know that C4 is not (much) the plastic explosive. Semtex is more plastic. But he has a lot of plasticizer. (19?) Markx: You're only used 5% plasticizer? Or 5% polybutylene and 5% methyl ricinoleate? Thank you, LL .............:cool:

markx - 25-11-2014 at 09:15

Quote: Originally posted by Laboratory of Liptakov  

Interesting post markx. To refresh your memory. C4:
RDX ................................................. .. 91.0%
Di (2-ethylhexyl) sebacat ........................ 5.3%
Polyisobutylene ....................................... 2.1%
oil (synthetic 5W?) .................................. 1.6%.
This is not many (9%) of a plasticizer. Usually (often) it is 15%. Q: Is it possible to replace Di (2-ethylhexyl) sebacat, methyl ricinoleate? If yes. Also use the 5.3%? I know that C4 is not (much) the plastic explosive. Semtex is more plastic. But he has a lot of plasticizer. (19?) Markx: You're only used 5% plasticizer? Or 5% polybutylene and 5% methyl ricinoleate? Thank you, LL .............:cool:


Good remark...I was unclear in my last post, mind rushed ahead of the fingers. Sometimes I tend to forget that the readers can not read minds...only the text :)
So yes, I used 5% polybutylene + 5% methyl riccinoleate for the shaped charge phlegmatisation purpose:

9g PETN/RDX
1g plastification mixture

plastification mixture: 50/50% by mass methyl riccinoleate/polybutylene


The sebacate in the original C4 composition can be replaced by the methyl riccinoleate. As for the exact ratio I do not know...one can start off with a 1:1 ratio and work ahead from there in either direction until a satisfactory result is obtained. I do not think though that the 1:1 replacement ratio happens to be the optimum one.

As I understand cyclonite tends to suffer significant losses in VoD and cap sensitivity if more than 10% inerts are incorporated into the mix...hence the 9% inerts content of the C4 composition and the "not so plastic" consistancy. In that sense PETN is way more forgiving and allows to work upwards of 20% inert content of formulations without significant limitations in either VoD nor cap sensitivity.


methylricinoleate

Laboratory of Liptakov - 25-11-2014 at 12:10

Oh, thank you, absolutely perfect answer. Everything was written true and legible letters and words. No secret thoughts were observed. In this situation it is clear that methyl-ricin-oleate will soon be manufactured and tested. LL .....:cool:

ecos - 28-11-2014 at 02:14

Hi,

I found this method to make high density blasting gel : Link

smokeup - 28-11-2014 at 23:40

I heard you use a normall solid binder, heat to liquid, mix, pour into mold, compress, wait to solidify.
Just make sure the heating and compressing dont trigger it.

Reflux condenser.

Laboratory of Liptakov - 1-12-2014 at 11:53

Cu tube 10/12, long 600mm.
Jacob's ladder condensation......:cool:...LL

reflux condenser.jpg - 43kB

markx - 2-12-2014 at 04:00

Quote: Originally posted by Laboratory of Liptakov  
Cu tube 10/12, long 600mm.
Jacob's ladder condensation......:cool:...LL



For the transesterification of castor oil? For that purpose it is overkill by function, but if one enjoys the process then why not. I personally would have just screwed the lid lightly on the glass jar to prevent the methanol from evaporating. In fact I have conducted the synthesis in an open flask without any problems and without any preventative measures to avoid the escape of methanol....it really is not that volatile by nature.

Hennig Brand - 2-12-2014 at 05:44

Methanol is quite toxic and its boiling point is less than 65C. I used a long piece of glass tubing and a rubber stopper to make a simple air cooled reflux condenser the last time I performed the trans-esterification reaction indoors. The heat transfer properties of copper are very much superior to glass (and pretty much every other common material); as long as the chemicals involved in a particular application are compatible with copper it can be used. Glass is much closer to being completely inert, however, and it provided all the cooling I needed.

methyl ricinoleate

Laboratory of Liptakov - 2-12-2014 at 07:39

Markx is right. No need cooler. Glasses can be closed. The steam pressure is small. Even at 80C cap holds. No problems. The temperature is maintained at 70C for 4 hours. A sample of the reaction: 19.5 g + 0.5 g of 96% H2SO4. It is necessary to wait for the separation of the layers. The lower part has to be glycerine and the upper portion of the solution of methyl ricinoleate. Distribution takes 12 hours ....? ....LL

markx - 2-12-2014 at 11:21

Quote: Originally posted by Laboratory of Liptakov  
A sample of the reaction: 19.5 g + 0.5 g of 96% H2SO4. It is necessary to wait for the separation of the layers. The lower part has to be glycerine and the upper portion of the solution of methyl ricinoleate. Distribution takes 12 hours ....? ....LL


Sulfuric acid? Did you use the acid catalysed transesterification process? Base catalysed transesterification tends to work much faster due to the reaction mechanism specifics:

http://www.icrepq.com/icrepq%2711/549-encinar.pdf

First separation of layers with base catalyst process can be observed quite quickly...in less than an hour from the start of reaction, but complete separation can take up to 12 hours (depending on ambient temperature).

r.oleate

Laboratory of Liptakov - 2-12-2014 at 13:26

I followed the instructions from page 5 this thread:
methylricinoleate.pdf
Unfortunately I have bad results, methyl ricinoleate failed to produce. I will return to this later. Thank you for your help and for the last link. I need very precise instructions. Machine translation trouble. Few understand. I do not want to be a burden.
I prefer to bring results. As is detonography etc. .......:cool:....LL

Glass Reaction Vessel Pressure Calculation

Hennig Brand - 2-12-2014 at 14:02

I decided to work through this, just for my own interest mostly. Assuming ideal behavior, will use Raoult's Law and Dalton's Law. I may have made calculation errors.

Information on castor oil came from this site:
http://www.scbt.com/datasheet-214671-castor-oil.html

Castor Oil - C57H104O9
MW = 933.61g/mol
Density = 0.961g/mL

Vapor pressure at 80C came from the following site:
http://www.engineersedge.com/fluid_flow/fluid_data.htm

Castor Oil Vapor Pressure at 80C ~= 0 kPa (very, very low)


Methanol - CH3OH
MW = 32.04g/mol
Density = 0.792g/mL
Vapor pressure at 80C ~= 182kPa
(Methanol values from Wiki pages)

Assume using equal volumes of castor oil and methanol as Nitro-
genes suggested here:
http://www.sciencemadness.org/talk/viewthread.php?tid=6151&a...

Basis of 100mL of each reactant

Moles of Castor oil = 100mL * (0.961g/mL) / (933.61g/mol) = 0.1029moles
Moles of Methanol = 100mL * (0.792g/mL) / (32.04g/mol) = 2.472moles

Mole Fraction of Castor oil in liquid = 0.1029 / (0.1029 + 2.472) = 0.040
Mole Fraction of Methanol in liquid = 2.472 / (0.1029 + 2.472) = 0.960

Pressure Total = Pvap_castor * X_castor + Pvap_MeOH * X_MeOH
Pressure Total = 0 * 0.040 + 182kPa * 0.960
Pressure Total = 174.72 kPa (atmospheric is 101.32kPa)

This is of course the maximum pressure at the start of the reaction at 80C; since as the methanol is consumed its liquid molar fraction will drop and so too will the internal pressure. I didn't account for the air in the head space, but its pressure will not be significant compared to the vapor pressure of methanol at 80C.

It is amazing how much internal positive pressure undamaged, well made, glass bottles can take. There is a big difference between a champagne bottle, built to handle pressure, and a thin walled pickle jar though. Also bottles, even of the same type, are never completely uniform and some have imperfections which make them much weaker. A small crack or imperfection can make a glass vessel fail at very low pressures.

Attached is a study done on glass bottle destructive testing.


Attachment: Analysis of Brittle Fracture of Soda Glass Bottles under Hydrostatic Pressure.pdf (274kB)
This file has been downloaded 282 times


[Edited on 3-12-2014 by Hennig Brand]

markx - 3-12-2014 at 00:55

174kPa would be the worst case scenario, assuming that the whole reactor is at 80C. If one uses a tall(ish) reactor with only the bottom part of reagents submerged in the thermostat then the upper part of reactor would act as a natural cooler, provoking condesation and relieving the pressure gradient significantly. And 80C in my personal experience is too much for practical transesterification. I speak of my own experiences and I have noticed that when you go that high with the temperature, you will saponify the oil, spend the hydroxide on it and are left with a sticky well emulsified mess of oil, soap and unreacted alcohols. It may look similar to transesterification at some stage, but the phase separation will never occur. So my suggestion would be to relax, turn the heat down and keep the catalyst content low. Try 40-50C and catalyst content below 1% oil mass (dissolve the alkali in the methanol beforehand). Nice mellow conditions at the expense of reaction time but no need for extra coolers, pressures will not burst reactors and ruin your day. At 50C the methanol vapour pressure should stay around 53kPa even if you submerge the whole system into the water bath.

Hennig Brand - 3-12-2014 at 02:13

Sounds like good suggestions. I haven't made any in several years. I made some two or three times, around that time, and I still have quite a bit of it left.

PHILOU Zrealone - 4-12-2014 at 08:20

Maybe something could be done with PVN (polyvinylnitrate = (-CH2-CHONO2-)n) as active, unsensitive plastic binder?
Density: 1.6 g/ccm
VOD: 7000 m/s @ 1.5 g/ccm (so 7600 m/s at max density)
Impact sensitivity: 10 Nm (IS PETN is 3 Nm)

For sure much better than common oils due to density increase and partly contributing to energy output.

Hennig Brand - 4-12-2014 at 12:33

As long as the desired handling properties could be obtained it sounds great. Handling properties would come first, I would imagine, when considering the binder & plasticizer components for a plastic explosive.

PVN

Laboratory of Liptakov - 4-12-2014 at 13:33

In advance thank you all for your valuable contributions to methyl ricinoleate. Also: Polyvinyl Nitrate? VOD 7000 m / s and more? But: Is it possible to produce? Glue Hercules, that is polyvinyl acetate. (contains PVA) Hydrolysis in methanol polyvinylalcohol arises. Polyvinyl alcohol is esterified (HNO3) on polyvinyl nitrate. He tried to anyone? We know how to do it? Here is my best plastic .....:cool:.......VoD 0,0 m/s

giraffe.jpg - 79kB

PHILOU Zrealone - 5-12-2014 at 05:37

Polyvinyl alcohol pouches were used when I was working at Procter&Gamble R&D lab.
You get tiny plastic like bags with the liquid soap inside (high dutty liquid).
The liquid soap had to contain as little as possible moisture in a way to keep the bag integer, avoid leakage and mass sticking of the pouches.

The bag (owing to the hydrophilic nature of the hydroxy groups (PVA = (-CH2-CHOH-)n) dissolves into the wash-machine when in contact with warm or tempered wash-water and set the washing liquid free into the hart of the clothes...

This technology is now common to encapsulate soaps for clothes and for dishwashing powders... ;)
So now everybody knows where to look for it :D




[Edited on 5-12-2014 by PHILOU Zrealone]

Hennig Brand - 5-12-2014 at 07:30

Very nice PHILOU, could you tell us a little bit about producing Polyvinyl Nitrate? It sounds like you have been through it and know what you are talking about.

PHILOU Zrealone - 5-12-2014 at 09:57

Same procedure as for polyols like cellulose nitrate, PETN, ETN.

Related compounds are ethyl nitrate, trimethylene glycol dinitrate and 1,3-butanediol dinitrate as being non viccinal nitric esters...there is a CH2 bridging between C holding a nitrate groupe.
H-(-CH2-CHONO2)n-H
n=1 CH3-CH2ONO2 = ethyl nitrate
n=2 CH3-CHONO2-CH2-CH2ONO2 = BGDN
n= Big = PVN
This family of compounds is linked to PETN family where the brindging is a C atom...they display good performances with low sensitivity to shock vs parent pernitrated polyols with one nitrate per C atom

[Edited on 5-12-2014 by PHILOU Zrealone]

polyvinylalcohol

Laboratory of Liptakov - 5-12-2014 at 11:50

Well done Phil. This is very important information. Polyvinyl Alcohol is thus a solid mass? A little plastic? It will be possible to use the empty container clean? A basic mixed acid? HNO3-65 / H2SO4-96%? 40:60? That's all? The reaction temperature to 5C as ETN? Or 25C like PETN? The package will be dissolved. Prior to esterification. Very interesting ....:cool:....LL

UnintentionalChaos - 5-12-2014 at 12:34

Working with castor oil is problematic, because you can also transesterify to the alcohol group on the fatty acid chain. You need a very large excess of methanol to avoid this. Also, usage of sulfuric acid will lead to ricinoleylsulfuric acid, where the alcohol is converted to a monosulfonate ester. The sodium salt of this material is called turkey red oil and is a historically used surfactant in dying processes.

markx - 6-12-2014 at 04:29

Polyvinyl alcohol with different degrees of polymerisation is commercially available in powder form....no need to scavange and grind up the sufactant capsules to obtain it :)

E.g.

http://www.carolina.com/specialty-chemicals-p-r/polyvinyl-al...

http://www.amazon.com/Polyvinyl-Alcohol-Purity-Powder-Bottle...

Just pick a source and order a sample...

It is widely used to encapsulate redispersion powder particles to prevent premature hardening during storage.

Polyvinyl nitrate

Laboratory of Liptakov - 6-12-2014 at 07:12

Good work markx. We're only a small step from perfect plasticizer. And that's not all. Polyvinyl nitrate can be used independently. Or widely represented in the mixture. Excellent substance. Universal. I hope to see you soon ....:cool:

markx - 6-12-2014 at 07:39

As a matter of fact I think that I still have a rather sizeable sample of POVAL brand PVOH powder somewhere in my lab....gotta keep an eye out for it. Was not much good for the purpose that I ordered it, but perhaps the "alternative use" shall prove more successful.
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