Sciencemadness Discussion Board

How to plasticize ETN with SBR (styrene-butadiene rubber)?

Weeblordd - 5-1-2024 at 10:07

I've read in various threads that ETN can be plasticized with styrene-butadiene rubber, apparently 9/1 ETN/SBR respectively makes a professional grade plastic explosive and I find that SBR rubber is OTC here easy to buy for cheap in large amounts. Can someone explain how to plasticize ETN or any high explosive with SBR rubber? or do you soften the SBR with toluene and add ETN to it, mold it up like playdough and you're good to go? This info is hard to find, give me some pointers please

sbr.png - 128kB

DennyDevHE77 - 5-1-2024 at 11:18

That's usually how it's done. The polymer dissolves in the right solvent (toluene \ gasoline \ and others) after which, right along with the solvent, it gets mixed (in a container so as not to spread) and as a result, a plastic explosive is obtained. I was also advised to grind everything in a mortar during mixing, this is good advice, but the mortar will get dirty all over.

Personally, I really prefer to use mouse adhesives, usually it is already an oil-diluted polymer, the main thing is to find the right one, not too diluted. And there you can mix it purely mechanically.

By the way, someone here made a good video about the extraction of polymer from tapes, but I don't remember who

I would also like to add that for a high-quality plastic substance, you need bimodal explosives. That is, two factions, large and small. This is important to achieve high density along with high ductility. I have already thrown earlier (although RDX with fluoro-organic), but I will reset it again.

"For a blend of 90-90.5% RDX, 3.5-4% fluoroorganics, and the rest is dibutyl phthalate:
1) RDX fraction <50µm 90% density = 1.38 g/ml [VoD 7220 m/s]
2) RDX fraction <50µm 45%, 200-250µm 45% density = 1.54 g/ml [VoD 7690 m/s]
3) RDX fraction <50µm 26.82%, 200-250µm 63.64% density = 1.58 g/ml [VoD 7920 m/s]
4) RDX fraction <50µm 26.82%, 120-200µm 63.64% density = 1.55 g/ml [VoD 7710 m/s]
5) RDX fraction <50µm 26.82%, 80-120µm 63.64% density = 1.51 g/ml [VoD 7640 m/s]
6) RDX fraction <50µm 38.5%, 100-300µm 51.95% density = 1.67 g/ml [VoD 8130 m/s]

Although this is of course fluoroorganics, and exotic for the home chemist, I think with hydrocarbon/fatty acid salt mixtures, or PiB, the difference would not be particularly large"

I have decided right now to convert the remains of petn (after the New Year celebration) into plastic, maybe I will show you some steps below

[Edited on 5-1-2024 by DennyDevHE77]

Sir_Gawain - 5-1-2024 at 11:28

It’s Laboratory of Liptakov. The type of tape that he uses can be hard to find, however.

fx-991ex - 5-1-2024 at 11:58

Quote: Originally posted by Sir_Gawain  
It’s Laboratory of Liptakov. The type of tape that he uses can be hard to find, however.

Scapa 2501, cant find it in canada, mostly from uk.

dettoo456 - 5-1-2024 at 19:35

Shoe GOO (sold in the US commonly) contains styrene-butadiene with Toluene and naphtha. You can try to experiment with that and some powdered sugar and solvent of choice. If you haven’t plasticized an EM before in a proven method before though, start with inert materials first.

DennyDevHE77 - 6-1-2024 at 02:33

Quote: Originally posted by DennyDevHE77  
I have decided right now to convert the remains of petn (after the New Year celebration) into plastic, maybe I will show you some steps below


Since I said it yesterday, here's how I make plastic.

First you have to find a surface, ideally a window sill, but in my case it's a sheet of foil on my desk, the kneading process is long and I'm watching anime. Do not forget to bend the sheet of foil, so that the explosives do not fall out (in my case PETN), as well as of course you need to measure the mass of your explosives.

plastic_1.png - 1.4MB

After that, pour out the PETN in a mound, and make a depression in the middle.

plastic_2.png - 1.6MB

Now you need to measure out the right amount of binder, in my case it's mouse glue. I have a total of 946 g of PETN, so I need 105 g of binder, for a 90/10 composition. With a glue density of 0.9, this is 116 ml. You can measure it with a syringe, for small amounts (but don't use a syringe for 20 ml or more, it's very heavy), or you can just pour it into a beaker.

plastic_3.png - 1.3MB

Then pour the glue into the depression in the mountain, and start kneading, it took me 5 series of 22 minutes to more or less mix everything.

plastic_4.png - 1.1MB

At some point you will get weird kinetic sand, but don't despair, just keep mixing, sooner or later you will be able to "glue" a significant amount of explosives into clumps.

plastic_5.png - 1.2MB

Then simple hand kneading becomes almost ineffective in such quantities, in my case I transferred all the PETN to the window sill, and began to roll with a rolling pin, this is also not fast. Here came out such pancakes. It is worth to roll them out. But first of all, I often use plastic explosive as a pressed composition. In the second part of the glue was left in the beaker and on the foil, so I guess I got the composition not 90 by 10, but 91 by 9, or even lower. Not good for plasticity, but it should be very good for pressing.

plastic_6.png - 1.2MB

I want to say right away that I do not advise you to make plastic in kilograms. It is better to do it a few times 100-200 grams at a time. It will be faster and of higher quality than a lot at once. And if you take 20-30 grams at a time, you can do without a rolling pin. Don't forget to wash it with gasoline afterwards, by the way.

[Edited on 6-1-2024 by DennyDevHE77]

dettoo456 - 6-1-2024 at 06:56

It looks like you have too much oil in your PBX, but it’d probably be fine for charges that won’t be malleable. The mouse glue isn’t high enough MW, usually a high MW polymer in conjunction with a small amount of oil and a plasticizer like DOP or DOS is used instead of a single, mid-range MW polymer.

The tear test is a good measure of plasticity; just pick up a clump of the plastic and try to tear it between both hands. It shouldn’t be too stringy or too loose and should tear cleanly after moderate force is applied. Modeling clay is a good target to match a PBX to.

Laboratory of Liptakov - 6-1-2024 at 11:41

SCAPA 2501 has 2 advantages. 1 - Contains PIB with ideal molecular weight. 2 - the black carrier does not dissolve in gasoline together with PIB. So the resulting PIB dissolved in gasoline is clear. With other self-vulcanizing tapes, the black carrier is also dissolved in gasoline. Which invalidates the result. For easy counting, it is advisable to adjust the concentration on 10% PIB in gasoline. The basic proportions are: 90g of powder (XY) + 50g of PIB in gasoline + 5g of 5W40 oil. After the gasoline evaporates during kneading, a composition of 90g xy + 10g binder is created. For high plastic properties is ratio: 88g xy + 50g (PIB in gasoline 10%) + 7 g 5W40. For shaped charge (press tools) is enough only 4% of basic binder. After pressing is material a like stone. Despite only 4% of binder.
https://www.youtube.com/watch?v=hB8mdSSKPoE

ManyInterests - 6-1-2024 at 22:09

Quote: Originally posted by DennyDevHE77  
That's usually how it's done. The polymer dissolves in the right solvent (toluene \ gasoline \ and others) after which, right along with the solvent, it gets mixed (in a container so as not to spread) and as a result, a plastic explosive is obtained. I was also advised to grind everything in a mortar during mixing, this is good advice, but the mortar will get dirty all over.

Personally, I really prefer to use mouse adhesives, usually it is already an oil-diluted polymer, the main thing is to find the right one, not too diluted. And there you can mix it purely mechanically.

By the way, someone here made a good video about the extraction of polymer from tapes, but I don't remember who

I would also like to add that for a high-quality plastic substance, you need bimodal explosives. That is, two factions, large and small. This is important to achieve high density along with high ductility. I have already thrown earlier (although RDX with fluoro-organic), but I will reset it again.

"For a blend of 90-90.5% RDX, 3.5-4% fluoroorganics, and the rest is dibutyl phthalate:
1) RDX fraction <50µm 90% density = 1.38 g/ml [VoD 7220 m/s]
2) RDX fraction <50µm 45%, 200-250µm 45% density = 1.54 g/ml [VoD 7690 m/s]
3) RDX fraction <50µm 26.82%, 200-250µm 63.64% density = 1.58 g/ml [VoD 7920 m/s]
4) RDX fraction <50µm 26.82%, 120-200µm 63.64% density = 1.55 g/ml [VoD 7710 m/s]
5) RDX fraction <50µm 26.82%, 80-120µm 63.64% density = 1.51 g/ml [VoD 7640 m/s]
6) RDX fraction <50µm 38.5%, 100-300µm 51.95% density = 1.67 g/ml [VoD 8130 m/s]

Although this is of course fluoroorganics, and exotic for the home chemist, I think with hydrocarbon/fatty acid salt mixtures, or PiB, the difference would not be particularly large"

I have decided right now to convert the remains of petn (after the New Year celebration) into plastic, maybe I will show you some steps below

[Edited on 5-1-2024 by DennyDevHE77]


Your description on using mouse glue is the most detailed I have ever seen. Mouse glue traps are everywhere where I live (Canada) but I once tried to use charcoal lighter fluid (a petroleum distillate) to dissolve it, but it failed. How do you get the mouse glue dissolved from the pads? I have toluene but I would rather use something else. Does the gasoline have to be gasoline from a gas station or is the petroleum distillate from charcoal lighter fluid/zippo lighter fluid sufficient and I just did something wrong?

I did have success with the victor rubber cement + bar & chain oil (all seasons), and while I think that all rubber cement nowadays is acid-free, I still would rather try something else.

fx-991ex - 7-1-2024 at 05:36

Quote: Originally posted by ManyInterests  
Quote: Originally posted by DennyDevHE77  
That's usually how it's done. The polymer dissolves in the right solvent (toluene \ gasoline \ and others) after which, right along with the solvent, it gets mixed (in a container so as not to spread) and as a result, a plastic explosive is obtained. I was also advised to grind everything in a mortar during mixing, this is good advice, but the mortar will get dirty all over.

Personally, I really prefer to use mouse adhesives, usually it is already an oil-diluted polymer, the main thing is to find the right one, not too diluted. And there you can mix it purely mechanically.

By the way, someone here made a good video about the extraction of polymer from tapes, but I don't remember who

I would also like to add that for a high-quality plastic substance, you need bimodal explosives. That is, two factions, large and small. This is important to achieve high density along with high ductility. I have already thrown earlier (although RDX with fluoro-organic), but I will reset it again.

"For a blend of 90-90.5% RDX, 3.5-4% fluoroorganics, and the rest is dibutyl phthalate:
1) RDX fraction <50µm 90% density = 1.38 g/ml [VoD 7220 m/s]
2) RDX fraction <50µm 45%, 200-250µm 45% density = 1.54 g/ml [VoD 7690 m/s]
3) RDX fraction <50µm 26.82%, 200-250µm 63.64% density = 1.58 g/ml [VoD 7920 m/s]
4) RDX fraction <50µm 26.82%, 120-200µm 63.64% density = 1.55 g/ml [VoD 7710 m/s]
5) RDX fraction <50µm 26.82%, 80-120µm 63.64% density = 1.51 g/ml [VoD 7640 m/s]
6) RDX fraction <50µm 38.5%, 100-300µm 51.95% density = 1.67 g/ml [VoD 8130 m/s]

Although this is of course fluoroorganics, and exotic for the home chemist, I think with hydrocarbon/fatty acid salt mixtures, or PiB, the difference would not be particularly large"

I have decided right now to convert the remains of petn (after the New Year celebration) into plastic, maybe I will show you some steps below

[Edited on 5-1-2024 by DennyDevHE77]


Your description on using mouse glue is the most detailed I have ever seen. Mouse glue traps are everywhere where I live (Canada) but I once tried to use charcoal lighter fluid (a petroleum distillate) to dissolve it, but it failed. How do you get the mouse glue dissolved from the pads? I have toluene but I would rather use something else. Does the gasoline have to be gasoline from a gas station or is the petroleum distillate from charcoal lighter fluid/zippo lighter fluid sufficient and I just did something wrong?

I did have success with the victor rubber cement + bar & chain oil (all seasons), and while I think that all rubber cement nowadays is acid-free, I still would rather try something else.

I think you can buy the glue separatly, like a refill package.

EF2000 - 7-1-2024 at 06:59

Quote: Originally posted by fx-991ex  

I think you can buy the glue separatly, like a refill package.

Here in Europe, liquid mouse glue is available in tubes (just like normal adhesives). Such tube can be seen in Liptakov's video about rat glue (here). DennyDev is apparently using same thing, maybe from bigger package.

If one insist on dissolving pads, same thing as with SCAPA tape applies: you need petroleum solvent and patience. Fuel-grade gasoline has too much additives. Charcoal lighter fluid should work, unless it's alcohol-based. Petroleum ether, non-chlorinated brake cleaner, household-grade gasoline, all should work with enough soak time. To be absolutely sure, there's pure heptane.

PLSHY - 7-1-2024 at 08:30

I have created a plastic explosives document, I hope you can get inspiration from it,This is a word document



[Edited on 7-1-2024 by PLSHY]

Attachment: PE.zip (2.1MB)
This file has been downloaded 267 times


ManyInterests - 7-1-2024 at 11:38

Quote:
I think you can buy the glue separatly, like a refill package.


I've never been able to find that. The only mouse glue I can find is through glue board traps for cockroaches and rodents. I did see rat glue on ebay, but it is very expensive and I am not sure if it is PiB.

Quote:

Here in Europe, liquid mouse glue is available in tubes (just like normal adhesives). Such tube can be seen in Liptakov's video about rat glue (here). DennyDev is apparently using same thing, maybe from bigger package.

If one insist on dissolving pads, same thing as with SCAPA tape applies: you need petroleum solvent and patience. Fuel-grade gasoline has too much additives. Charcoal lighter fluid should work, unless it's alcohol-based. Petroleum ether, non-chlorinated brake cleaner, household-grade gasoline, all should work with enough soak time. To be absolutely sure, there's pure heptane.


Yes, whenever I look at charcoal lighter fluid, I always make sure it says that it is petroleum distillate and not methanol or other fluids. I did hear that mogas (motor gas) is no good for this and would need to be redistilled. I have some diethyl ether starter fluids that also contain heptane. Perhaps after distilling the diethyl ether I will have most of the heptane left over for use...

I've seen LL's video using rat glue. but the plastic it made was ultra crumbly and fell apart fast. I was not impressed.

I should mention that I have seen lip gloss base here and here that state they have PiB and possibly some other stuff that could aid in making PE without further processing. But I have been hesitant to give them a go.

Quote:
I have created a plastic explosives document, I hope you can get inspiration from it,This is a word document


Thanks. I'll give it a look.

ManyInterests - 7-1-2024 at 12:09

Quote: Originally posted by PLSHY  
I have created a plastic explosives document, I hope you can get inspiration from it,This is a word document



[Edited on 7-1-2024 by PLSHY]


I've looked at most of it. It is a good guide, but upon looking at it I still have the same problems... I don't know where to get dioctyl sebacate or pure PiB. That's always been my issue. It isn't how to plasticize so much as it is obtaining the raw materials.

Like I can get SBR as the OP said, but I guess how to properly dissolve that and extract such is the issue, everything else is gravy as they say.

dettoo456 - 7-1-2024 at 17:59

SBR is common enough to find in lots of places as a pure polymer and you can just dissolve it directly into Toluene. DOS can be found as a lubricant for pistons or as an ingredient sold by some cosmetic suppliers. Alternatively, DOP can be used is probably easier to come by. And mineral oil is extremely easy to find. Just blend the 3 ingredients up with your active ingredient and your PBX is done.

Lithium grease can also be used in a pinch.

ManyInterests - 7-1-2024 at 19:02

Quote: Originally posted by dettoo456  
SBR is common enough to find in lots of places as a pure polymer and you can just dissolve it directly into Toluene. DOS can be found as a lubricant for pistons or as an ingredient sold by some cosmetic suppliers. Alternatively, DOP can be used is probably easier to come by. And mineral oil is extremely easy to find. Just blend the 3 ingredients up with your active ingredient and your PBX is done.

Lithium grease can also be used in a pinch.


Amazon.ca sells sheets of SBR really cheap. I guess if I need to use of my toluene (I intend to turn it all into TNT) I will. Pure toluene is sold near me and isn't expensive. Around 16$ (tax included) for 946ml. I got two of those cans on hand.

Mineral oil is everywhere, I agree. In fact, I should buy a small bottle of it just in case I need it.

Also what is DOP? I assume DOS is Dioctyl Sebacate, but what is DOP? Also you mentioned MW. I am not sure if I caught what that meant.

Lithium grease and rubber cement is probably going to be the route I go with for inert plasticizers. For energetic binders, DEGDN will probably my choice once I make some.

dettoo456 - 8-1-2024 at 07:43

DOP is dioctyl phthalate; more common than DOS but more carcinogenic. If you want to ever have kids, I’d stay away from phthalates in general.

Lithium grease (just lithium stearate with some added oil) has been used with paraffin, RDX, and PETN to formulate PE4; a British PBX that’s apparently more brisant and easier to initiate than C-4. It seems to perform fairly well in comparison to other PBXs with more exotic polymers too. So if you have lithium grease available it could prove useful.

I’d stay away from DEGDN if I were you though, unless you’re casting your EM permanently. Handling nitrate esters is a headache, literally and figuratively. DEGN has the lowest toxicity iirc compared to NG, EGDN, and TEGDN, but it’ll still have sensitivity and storage issues.

https://apps.dtic.mil/sti/citations/ADA164484

https://en.m.wikipedia.org/wiki/Talk:C-4_(explosive)

EF2000 - 8-1-2024 at 10:53

Quote: Originally posted by dettoo456  


Lithium grease (just lithium stearate with some added oil) has been used with paraffin, RDX, and PETN to formulate PE4; a British PBX that’s apparently more brisant and easier to initiate than C-4. It seems to perform fairly well in comparison to other PBXs with more exotic polymers too. So if you have lithium grease available it could prove useful.

https://apps.dtic.mil/sti/citations/ADA164484

https://en.m.wikipedia.org/wiki/Talk:C-4_(explosive)

PE4 is 88% RDX, 8% paraffin oil, 3% lithium stearate, 1% pentaerythritol dioleate (+0.1-1% taggant). Last one is hardly essential. And lithium stearate+mineral oil is a plain lithium grease.
(Newer plastic explosives from the land of black tea are different, PE7 contain poshy HTPB, and PE8 is more like C-4 with more binder and less RDX).

Old Soviet PE, PVV-4 was just 80% RDX, 20% calcium grease (3:1 motor oil and calcium stearate).


DennyDevHE77 - 8-1-2024 at 11:12

Interestingly, PVV-4 was slightly weaker than TNT. It had a density of 1.42 g/ml, and a Hess brisance of 21 mm.

A little later, a modified PVV-5A was released, with a rdx content of 85%, but its density was 1.4 g/ml. and it was slightly weaker, with a Hess brisance of 20 mm.

But there was also GP-87K hexoplast with 82% rdx, but the density. 1.55, and a brisance of 26 mm.

In general, it seems that density plays a much greater role than the content of the main explosive, while ensuring excellent plasticity with a plasticizer content of 15-20% is much easier than with 9%. Perhaps the high coefficient of plastic filling has a role for the critical diameter, and the ease of susceptibility to detonation.

DennyDevHE77 - 8-1-2024 at 11:24

Quote: Originally posted by EF2000  
DennyDev is apparently using same thing, maybe from bigger package.


Well, personally, I use glue ALT of the composition polybutylene – 80.83%, polyisobutylene – 9.60%, cyclosane – 9.57%, I do not know what cyclosane is, maybe this is the trade name of the stapler. There are other adhesives where the polymer is diluted with oil. But this adhesive uses a mixture of high molecular weight and low molecular weight polymers. Some people warm it and get only the high molecular weight polymer, but I haven't done that.

We have adhesives based on butadiene acrylonitrile and styrene butadiene rubber on sale, but since these are polymers with unsaturated bonds, they are susceptible to oxidation and aging. As far as I know, the first semtex were on a similar binder, and they deteriorated after 4 years.

There are also many silicone-based adhesives, but as far as I know, silicone polymers are not the best choice for plastic explosives due to their strong negative effect on the detonation rate.

[Edited on 8-1-2024 by DennyDevHE77]

ManyInterests - 8-1-2024 at 14:53

Quote: Originally posted by dettoo456  
DOP is dioctyl phthalate; more common than DOS but more carcinogenic. If you want to ever have kids, I’d stay away from phthalates in general.

Lithium grease (just lithium stearate with some added oil) has been used with paraffin, RDX, and PETN to formulate PE4; a British PBX that’s apparently more brisant and easier to initiate than C-4. It seems to perform fairly well in comparison to other PBXs with more exotic polymers too. So if you have lithium grease available it could prove useful.

I’d stay away from DEGDN if I were you though, unless you’re casting your EM permanently. Handling nitrate esters is a headache, literally and figuratively. DEGN has the lowest toxicity iirc compared to NG, EGDN, and TEGDN, but it’ll still have sensitivity and storage issues.

https://apps.dtic.mil/sti/citations/ADA164484

https://en.m.wikipedia.org/wiki/Talk:C-4_(explosive)


I am aware of the permanentness of using DEGDN. So what my plan is that I only plasticize my energetic powder as needed. I would not plasticize it with an energetic binder for storage. I am also very aware of nitro headaches (and more dangerously: nitroheart). The result is that I NEVER EVER handle any energetic material with my bare hands. I always use nitrile/vinyl/latex gloves, sometimes in combination with a thin polyethylene glove on top of that for added protection.

For lithium grease, I did look at the composition of the grease and I also looked at a WW2 era Japanese plastic explosive that also used lithium grease and some wheel-bearing grease as a plasticizer. I am sure that it isn't as powerful or as good as C4, but it is good enough.

EDIT: My main use for DEGDN is to use it as a NG substitute to make smokeless gunpowder down the line.

Quote: Originally posted by DennyDevHE77  
Interestingly, PVV-4 was slightly weaker than TNT. It had a density of 1.42 g/ml, and a Hess brisance of 21 mm.

A little later, a modified PVV-5A was released, with a rdx content of 85%, but its density was 1.4 g/ml. and it was slightly weaker, with a Hess brisance of 20 mm.

But there was also GP-87K hexoplast with 82% rdx, but the density. 1.55, and a brisance of 26 mm.

In general, it seems that density plays a much greater role than the content of the main explosive, while ensuring excellent plasticity with a plasticizer content of 15-20% is much easier than with 9%. Perhaps the high coefficient of plastic filling has a role for the critical diameter, and the ease of susceptibility to detonation.




Quote: Originally posted by DennyDevHE77  
Quote: Originally posted by EF2000  
DennyDev is apparently using same thing, maybe from bigger package.


Well, personally, I use glue ALT of the composition polybutylene – 80.83%, polyisobutylene – 9.60%, cyclosane – 9.57%, I do not know what cyclosane is, maybe this is the trade name of the stapler. There are other adhesives where the polymer is diluted with oil. But this adhesive uses a mixture of high molecular weight and low molecular weight polymers. Some people warm it and get only the high molecular weight polymer, but I haven't done that.

We have adhesives based on butadiene acrylonitrile and styrene butadiene rubber on sale, but since these are polymers with unsaturated bonds, they are susceptible to oxidation and aging. As far as I know, the first semtex were on a similar binder, and they deteriorated after 4 years.

There are also many silicone-based adhesives, but as far as I know, silicone polymers are not the best choice for plastic explosives due to their strong negative effect on the detonation rate.

[Edited on 8-1-2024 by DennyDevHE77]


Meh, you know what, after reading all this, I'll be OK with using rubber cement. I think my fear of the acidity in them is not founded. Since wikipedia does say that it is only older formula rubber cements have a low pH, the newer ones (and by newer I think it is very early 2000s) are not acidic.

[Edited on 8-1-2024 by ManyInterests]

EF2000 - 9-1-2024 at 00:26

Quote: Originally posted by DennyDevHE77  


We have adhesives based on butadiene acrylonitrile and styrene butadiene rubber on sale, but since these are polymers with unsaturated bonds, they are susceptible to oxidation and aging. As far as I know, the first semtex were on a similar binder, and they deteriorated after 4 years.

[Edited on 8-1-2024 by DennyDevHE77]

Semtex has SBR as binder and octyl phtalate+butyl citrate as plasticizer. And 1% of N-phenyl-2-naphtylamine as antioxidant, maybe that solves oxidation problem. That's for 1A and H variants, new types may be completely different, Semtex 10 has acrylonitrile–butadiene and dibutylformamide (according to that paper, that cites manufacturer report that I can't find).


Quote: Originally posted by ManyInterests  


I'll be OK with using rubber cement. I think my fear of the acidity in them is not founded. Since wikipedia does say that it is only older formula rubber cements have a low pH, the newer ones (and by newer I think it is very early 2000s) are not acidic.

To be absolutely sure, you can make a sample with inert filler and some pH indicator powder (like litmus blue or methyl orange). And monitor it a bit for color changes.

PLSHY - 9-1-2024 at 02:07

Quote: Originally posted by DennyDevHE77  
Interestingly, PVV-4 was slightly weaker than TNT. It had a density of 1.42 g/ml, and a Hess brisance of 21 mm.

A little later, a modified PVV-5A was released, with a rdx content of 85%, but its density was 1.4 g/ml. and it was slightly weaker, with a Hess brisance of 20 mm.

But there was also GP-87K hexoplast with 82% rdx, but the density. 1.55, and a brisance of 26 mm.

In general, it seems that density plays a much greater role than the content of the main explosive, while ensuring excellent plasticity with a plasticizer content of 15-20% is much easier than with 9%. Perhaps the high coefficient of plastic filling has a role for the critical diameter, and the ease of susceptibility to detonation.
At the same time as the content of inert substances, the theoretical density of plastic explosives is generally close, because the densities of most inert substances are close, about 0.9g/ml. At this time, the importance of actual density becomes apparent. For example, 5pib 2dos 2oil 90petn has better plasticity than 2pib 5dos 2oil 90petn, and the two have almost the same theoretical density, but due to the lubrication effect of DOS, the latter has a higher actual use density, so the actual performance of the latter is stronger to the former. And this effect also extends to plastic explosives with different inert material contents, and may even cause some explosives with high inert material content to be stronger than explosives with low inert material content.

ManyInterests - 10-1-2024 at 17:01

Quote:
To be absolutely sure, you can make a sample with inert filler and some pH indicator powder (like litmus blue or methyl orange). And monitor it a bit for color changes.


Oh shit! I didn't think about that. I wanted to ask how I would test the stuff to see if it was acidic or not. Seems like that's the answer. I have litmus paper and methyl blue (liquid) but I guess that's not it. I'll shop around for some litmus blue and methyl orange. Once I have them handy, I'll measure out some fine all-purpose flour (which makes for an excellent inert material to test) and plasticize it, then see what happens.

Edit: https://shorturl.at/yCEVY Would this product work? I just want to make sure.

[Edited on 11-1-2024 by ManyInterests]

EF2000 - 11-1-2024 at 04:21

Quote: Originally posted by ManyInterests  


Oh shit! I didn't think about that. I wanted to ask how I would test the stuff to see if it was acidic or not. Seems like that's the answer. I have litmus paper and methyl blue (liquid) but I guess that's not it. I'll shop around for some litmus blue and methyl orange. Once I have them handy, I'll measure out some fine all-purpose flour (which makes for an excellent inert material to test) and plasticize it, then see what happens.

Edit: https://shorturl.at/yCEVY Would this product work? I just want to make sure.

[Edited on 11-1-2024 by ManyInterests]

No, it's "Buffer Solution Powder". It's for making a solution with known pH and testing your pH-meter.

Methyl blue is useful stain for histology, but not indicator. Methyl orange turns red at 3.1, litmus at 4.5. Also, the change from purple to red is more noticeable. So I recommend litmus.
Both are available as pretty fine powders.

ManyInterests - 11-1-2024 at 21:12

https://shorturl.at/vGWZ3

Would something like this work? I tried to find a seller of litmus powder, but they were either not shipping or prohibitively expensive. Would this work? Also what if I just made the mixture of the oil and rubber cement, then used a pH strip? If the liquid is neutral, then it all should be good, right?

EF2000 - 11-1-2024 at 22:37

Quote: Originally posted by ManyInterests  
https://shorturl.at/vGWZ3

Would something like this work? I tried to find a seller of litmus powder, but they were either not shipping or prohibitively expensive. Would this work? Also what if I just made the mixture of the oil and rubber cement, then used a pH strip? If the liquid is neutral, then it all should be good, right?

I have another idea. Ethanol is miscible both with petroleum solvents in rubber cement and with mineral oil. You can extract anthocyanines from, say, hibiscus tea. And add that alcohol solution to rubber+oil mix.

Microtek - 12-1-2024 at 00:55

Denny, when you say:

Quote:

There are also many silicone-based adhesives, but as far as I know, silicone polymers are not the best choice for plastic explosives due to their strong negative effect on the detonation rate.


Do you have any sources for that? From the papers I've read, it seems that silicone based plastiques are technically about as good as hydrocarbon polymers, but the price is higher.

DennyDevHE77 - 12-1-2024 at 09:34

I'll be honest, I wrote this because I remembered an ancient discussion on a dead forum. I found it in the web archive, and unfortunately the opponents didn't leave a list of references to sources :(

So my thesis unfortunately smells of an appeal to authority. It's just that those guys were in 2000-2003 (up to 2012) essentially the founders of the hobby of making HEDM at home. But the posts themselves date back to 2006. Actually here are these comments:

"It is equally significant that organosilicon polymers give lower velocity characteristics in plastic explosives (negative influence of Si atom) than hydrocarbon polymers (gross formula of ALT glue[-C4H8-]n ), for example, in PETN/Binder 87/13, in the case of silicone, the calculated velocity increase in porous explosives is 0.39 km/s, while with ALT it is 0.86 km/s."

"Somewhere there were official data on impromptu with PETN and ligaments with the same content. Butyl rubber is the leader in terms of detonation speed, followed by polyisobutylene, and polysiloxane (i.e. silicone) is the worst of all, showing itself almost 0.5 km/s worse.In any case, it is better to use what you can buy at the market than to go to the chemical stores"

So forgive Microtek for not being able to provide any more substantial evidence, I can of course dig the internet for 2000-2007, but that may not make sense. And the archive page itself is here, in general, you can find these comments there too, if you need (https://web.archive.org/web/20160418142955/http://www.explod...)

[Edited on 12-1-2024 by DennyDevHE77]

dettoo456 - 12-1-2024 at 14:02

The silicone binders are also not moldable I assume. So they’d be horrible if you want a ‘plastic’ plastic explosive. If you’re just casting though, they’d be fine.

ManyInterests - 12-1-2024 at 17:42

Quote: Originally posted by EF2000  
Quote: Originally posted by ManyInterests  
https://shorturl.at/vGWZ3

Would something like this work? I tried to find a seller of litmus powder, but they were either not shipping or prohibitively expensive. Would this work? Also what if I just made the mixture of the oil and rubber cement, then used a pH strip? If the liquid is neutral, then it all should be good, right?

I have another idea. Ethanol is miscible both with petroleum solvents in rubber cement and with mineral oil. You can extract anthocyanines from, say, hibiscus tea. And add that alcohol solution to rubber+oil mix.


Now THAT sounds more fun and dooable. Also a lot cheaper.

dettoo456 - 13-1-2024 at 18:38

[I edited this comp from 0.3 to 0.45g low MW PIB(or mineral oil) since it dried out a little over storage]

Around 50ml Mineral spirits (any aromatic paint thinner), 3.6g SBR (Shoe Goo), and 0.45g low MW PIB (substitute for mineral oil) can be mixed together well in an aluminum bowl.

*This mix won’t completely dissolve, but will swell the SBR; it’ll need to be kneaded into the solids*

Then 22.7g all purpose flour (combustible material) can be added to the bowl and thoroughly mixed with the liquid mixture. The ‘dough’ should afterwards be strongly mixed with a spatula every 20min for about 2 hours or until the mineral spirits completely evaporate - a stand mixer might be preferable for a task like this. Gentle heat can be applied but air drying or sitting under a fan is recommended.

The resulting composition is perfectly pliable, tacky, leaves no residue on surfaces, and has a good amount of stretch before tearing.

Ratios can be adjusted to meet users’ needs, but this mix is straight from the hardware store and preps in <4hrs. I haven’t measured density or seen long term storage stability yet.

[Edited on 14-1-2024 by dettoo456]

[Edited on 14-1-2024 by dettoo456]

ManyInterests - 13-1-2024 at 23:38

Quote: Originally posted by dettoo456  
Around 50ml Mineral spirits (any aromatic paint thinner), 3.6g SBR (Shoe Goo), and 0.3g low MW PIB (substitute for mineral oil) can be mixed together well in an aluminum bowl.

*This mix won’t completely dissolve, but will swell the SBR; it’ll need to be kneaded into the solids*

Then 22.7g all purpose flour (combustible material) can be added to the bowl and thoroughly mixed with the liquid mixture. The ‘dough’ should afterwards be strongly mixed with a spatula every 20min for about 2 hours or until the mineral spirits completely evaporate - a stand mixer might be preferable for a task like this. Gentle heat can be applied but air drying or sitting under a fan is recommended.

The resulting composition is perfectly pliable, tacky, leaves no residue on surfaces, and has a good amount of stretch before tearing.

Ratios can be adjusted to meet users’ needs, but this mix is straight from the hardware store and preps in <4hrs. I haven’t measured density or seen long term storage stability yet.


Thanks for the instructions. I like stuff like that. I assume the 0.3g low MW PIB (you haven't told me what MW means) can be substituted with bar and chain oil or another motor oil?

Laboratory of Liptakov - 14-1-2024 at 00:40

MW = molecular weight. Usually is number among 10.000 - 1000.000 Repeated search failed to find MW for Scapa 2501.

dettoo456 - 14-1-2024 at 06:26

Scapa has too high MW (and viscosity) I believe. You can substitute the low MW PIB for mineral oil and perhaps chain or motor oil. I think chain and/or motor oil might be have too low viscosity though.

If anyone knows also, can stabilizers like DPA, 2-NDPA, or centralite-1 be added to PBXs (nitrate ester based) and still have the same stabilizing effect or would they be useless in that case? Compounds such as DPA, 2-NDPA, and centralite are all soluble in acetone but insoluble in water, so I figured a co-mixture with ETN or PETN could be produced fairly easily via the anti solvent method and the resulting solid would have better stor-ability.

[Edited on 14-1-2024 by dettoo456]

Etanol - 14-1-2024 at 07:55

Quote: Originally posted by dettoo456  
Compounds such as DPA, 2-NDPA, and centralite are all soluble in acetone but insoluble in water, so I figured a co-mixture with ETN or PETN could be produced fairly easily via the anti solvent method and the resulting solid would have better stor-ability.
[Edited on 14-1-2024 by dettoo456]

DPA is soluble in acetone, insoluble in water, but soluble enough in acetone-water mix. I had problems with this. Other way insert DPA to PETN is need.

dettoo456 - 16-1-2024 at 15:51

Quote: Originally posted by dettoo456  
[I edited this comp from 0.3 to 0.45g low MW PIB(or mineral oil) since it dried out a little over storage]

Around 50ml Mineral spirits (any aromatic paint thinner), 3.6g SBR (Shoe Goo), and 0.45g low MW PIB (substitute for mineral oil) can be mixed together well in an aluminum bowl.

*This mix won’t completely dissolve, but will swell the SBR; it’ll need to be kneaded into the solids*

Then 22.7g all purpose flour (combustible material) can be added to the bowl and thoroughly mixed with the liquid mixture. The ‘dough’ should afterwards be strongly mixed with a spatula every 20min for about 2 hours or until the mineral spirits completely evaporate - a stand mixer might be preferable for a task like this. Gentle heat can be applied but air drying or sitting under a fan is recommended.

The resulting composition is perfectly pliable, tacky, leaves no residue on surfaces, and has a good amount of stretch before tearing.

Ratios can be adjusted to meet users’ needs, but this mix is straight from the hardware store and preps in <4hrs. I haven’t measured density or seen long term storage stability yet.

[Edited on 14-1-2024 by dettoo456]

[Edited on 14-1-2024 by dettoo456]


This composition dried out too much during storage out in the open at room temp. I handled it multiple times over the course of 3 days to test plasticity and I believe that too much oil was absorbed into my skin or transferred away.

It still remained pliable and soft but was simply too dry. I will replace (either fully or in part) the low MW PIB/mineral oil with Vaseline and maybe beeswax to see if they produce a product with better results.

If anyone has any insight on SBR PBXs please feel free to add or critique.