Di-(2-ethylhexy)sebacate - Archive File

[megalomania]

mongo blongo
Frequent Poster
Posts: 175
From: I live in a Creosote Bush!
Registered: JUN 2001
posted 07-13-2001 11:17 PM
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Is Di-(2-ethylhexy)sebecate used in C4?
i have never seen this stuff!
I cant find a single post on it. Not even anything on the NET!
What the hell is this stuff?
Where can this be obtained/or how can it be made?
What is it's purpose in C4?
Any help will be great!!!

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i like blowing shit up



cutefix
Frequent Poster
Posts: 330
From: california
Registered: MAY 2001
posted 07-14-2001 01:14 AM
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I think the reason why you cannot find it in the net is you misspelled it.It should be Di(2-ethyl hexyl) sebacate ,synonymous to Diiso-octyl sebacate.This material is a plasticizer,like polyisobutylene.Better checkTim Lewis Kitchen improvised plastic explosives2 so that you can learn more about its purpose in C-4.
For MSDS check:
http://www.redox.com.au/msds/msds.data/ETHESE.HTM

[This message has been edited by cutefix (edited July 14, 2001).]



mongo blongo
Frequent Poster
Posts: 175
From: I live in a Creosote Bush!
Registered: JUN 2001
posted 07-14-2001 08:49 AM
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Nice one dude!!
Shit I don't know how this got posted twice!


mongo blongo
Frequent Poster
Posts: 175
From: I live in a Creosote Bush!
Registered: JUN 2001
posted 07-16-2001 04:30 PM
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Right just looked at Kitchen improvised plastic explosives2 from http://www.section1.f2s.com/files.html
It doesn't say much dude.
I still do not know much about it's purpose in C4 or where to get it/make it.


cutefix
Frequent Poster
Posts: 330
From: california
Registered: MAY 2001
posted 07-16-2001 08:03 PM
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Ethyl hexyl sebacate is one of the plasticizers for making plastic explosives like C-4.Regarding sources,i think you have to find that from chemical supplies,anyway there is already a specs listed in that website I listed before.

[Dave Angel]

I have been scouring the web for information on this substance and came across a pdf detailing the composition of oils, in which it stated that the sebacic acid used in the manufacture of sebacates is from castor oil. This got me thinking that it can't be too hard to synthesise a sebacate from widely available OTC products by way of a transesterification: The conversion of an ester of one alcohol into the ester of another.

In the case of di-(2-ethylhexy)sebacate the alcohol used would be 2-ethylhexanol. Unfortunately, AFAIK, 2-ethylhexanol is not available OTC so another alcohol will have to be used in its place. In my synthesis below, I used IPA as it is readily available in relatively high purity as a cleaner for electronics. If my nomenclature is correct, it should give the product di-(methyethyl)sebacate, which will probably have a lower viscosity than di-(2-ethylhexy)sebacate owing to the sorter chained alcohol. This may or may not be a problem in using it as a subtitute for the latter, and will require further investigation.

Also, one would ideally use KOH as the catalyst due to its higher solubility in the alcohol, but NaOH is much easier to get hold of.

The only difficulty I can see with this home synthesis is the refluxing step. I have the luxury of a reflux condenser, but I thought that if I didn't, I might try using a pressure cooker to keep the liquids from boiling away whilst they were heated. Having said that, I wouldn't want the over pressure valve venting alcohol vapor everywhere, especially if I was using gas...

In my synthesis, I used:

500mL IPA
400mL Castor Oil
17g NaOH (dried as best as possible, water must be kept to a minimum)

Procedure:

Dissolve 17g of NaOH into 500mL of IPA, (not all of this dissolved in my case, but it was the amount I calculated was appropriate.)

Stir the solution into 400mL of Castor Oil. I continued stirring for about an hour before realising that on a cold winters night at 3 degrees above zero, the reaction would need some heating to get anywhere.

Once thoroughly mixed, pour into a rb flask with a condenser and reflux it to boiling for 9 hours. This was perhaps a bit excessive, but the excess NaOH only started to dissolve after about 3 hours indicating that only then was significant product being formed.

Leave to cool only until it stops boiling and then pour into a suitably sized pyrex bowl. A tall jar would probably be better, but at this stage was not large enough to accomodate the product and the first lot of washing water. In fact a separating funnel would be ideal if available.

Now all that it left is to wash the product. Pour plenty of hot water into the mix and stir it well. Leave it to settle and the layers should separate until the lower water layer will be milky - full of impurities such as glycerol, soap, NaOH, excess IPA, and the upper layer will be an off-yellow oil, the sebacate.

Pipette the top layer off (turkey baster?) and into another jar into which hot water is again poured and stirred in. Repeat the process so that sebacate is thoroughly washed and the water layer is clear. It's a good idea to pipette the product into a container for storage whilst it is still hot and easier to handle due to its lower viscosity.

I obtained about 260g of product with this method.