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Post by Anders Hoveland on Mar 2, 2011 15:44:06 GMT -8
This forum is intended to be temporary until the well known "Explosives and Weapons" Forum becomes operational.
This forum, however, focuses more on the chemistry of lesser known reactions and lesser known energetic compounds. In other words, this forum contains unique advanced information which has generally not previously appeared in these types of forums.
You can help advertise this forum by going to other chemistry, pyrotechnic, or rocket forums.
Please feel free to post whatever comments you have about this forum below. You do not even have to be registered to leave a post.
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Post by Anders Hoveland on Apr 1, 2011 11:53:43 GMT -8
If one of the readers of knowledgeable enough, you can help by doing the calculations and writing a theoretic procedure for the topic "4-amino,5-nitro-1,2,3-triazole Preparation" (preferably use the route described in the second post, as there should be doubts about whether the nitro group in the desired product can survive in acetic anhydride, diluting it may be somewhat complicated)
Please post your comments about this site here, or if you feel you are knowledgable enough, PLEASE post your comments in the various topics. YOU DO NOT HAVE TO REGISTER TO MAKE A POST. You can give your opinion about a reaction, or just say whether you find the idea interesting or not.
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Post by Anders Hoveland on May 18, 2011 0:12:01 GMT -8
I changed the color scheme of the message board. Hopefully it will make things more interesting and help reduce glare. Still making small adjustments however.
I see there are some visitors. Feel free to make a post about what you think. Remember, you do not need to register in order to make a post, although this message board makes you look at an advertisement in order to make a post if you are not registered. Sorry for that.
Also if you have any requests about what you would like to see in this forum, you can contact andershoveland@sorensen.dk but it is better to leave a post for me in one of the other forums I have posted in.
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Post by Anders Hoveland on Aug 5, 2011 1:14:39 GMT -8
Chemical research into energetic materials is greatly underfunded. There are only about 25 energetic researchers in the USA, and about half of them do not do research full time (since they are university professors with teaching responsibilities).
TNT and RDX/HMX are both useful explosives, relatively safe with good performance, and much cheaper to produce than any of the new explosives. The US air force has begun to mix NTO into the TNT in some of its bombs, but besides that none of the new explosives have found their way into actual use.
These new explosives would be far less expensive (although still not nearly as cheap as the currently used ones) if they were produced on a large scale, but military forces do not have much incentive to convert over to begin with. Considering that a typical missile can cost between 200,000 and 2 million USD, using a more expensive explosive would not significantly add to the cost.
Fox-7 currently costs between 1000-3000 USD per kilogram. TNAZ currently costs several thousand USD per kilogram, but it has been estimated that the costs could go down to 200 if the production was scaled up.
Considering all the money spent on envirormental cleanups of explosive residue, and the big cost savings that can be achieved by reducing weight, a few thousand dollars is really insignificant. It was even estimated that the melt-castability of TNAZ would reduce manufacturing difficulties enough to pay for itself through reduced labor costs.
Even though it makes economic sense to converty to new explosives, current military officials are too thick-headed to ever make the conversion, especially in the USA with all the budget-cuts.
The chlorination of trinitroaniline would likely form dinitrobenzofuroxan, which would be moderately more powerful than TNT, with about the same sensitivity. Trinitroaniline itself is somewhat chemically unstable, bulk quantities can detonate by themselves in storages, but despite the risk this explosive was used by Japanese suicide bombers in the Pacific.
My personal, fairly well informed opinion, is that stable, relatively safe, explosives could potentially be developed which are significantly more powerful. There is, of course, an effective limit to how powerful chemical explosives can be. Unfortunately, there seems to be somewhat of a trade-off between safety and power.
I think the upper limits of chemical explosives are around 4 to 7 times the power of HMX, despite the fact that nothing close to this has ever actually been achieved. Note, this is the upper estimate, and such explosives would likely be to sensitive, unstable, and/or toxic to find practical use. Such compounds would likley incorporate fluorine (perhaps in the form of -NF2 or -SF5 groups), boron, or beryllium atoms.
In terms of practical limits for potential military explosives, it is very difficult to speculate. At least from the measurements of compounds which have actually been synthesized, the effective limit seems to be around only 30% more power than HMX, not really much of an improvement. A few of the compounds I have proposed in my site might reach 35 to 50% more power than HMX, but this is just conjecture.
It has been calculated by researchers that DTTO, if synthesized, may reach up to 45% more power than HMX. Both octonitrocubane and DTTO would probably be a litte too sensitive by itself, but perhaps could be rendered safe enough for use by being mixed with one of the new high-performance lower-sensitivity explosives. TNAZ, for example, is not only comparable to HMX in terms of power, but it is also slightly lighter weight, significantly less sensitive, and with the desirable property of melt-castability. Basically, it outperforms composition B and C-4.
Some of the tetrazole compounds that have been synthesized have been both more powerful, and less sensitive than HMX. These tetrazole compounds are relatively easy to prepare in laboraties, but more difficult to scale up manufacturing, since processing large quantities of hydrazoic acid can easily result in explosion. Another disadvantage of the tetrazole family is that the compounds can become extremely sensitized by traces of strong bases (such as sodium hydroxide).
Not all of the new explosives will be more powerful. Many of them are less powerful than RDX, but show good physical properties or improved safety, while still showing improved performance over TNT. One example is LLM-105. While some of these compounds only show small improvement over current explosives, considering the high cost of the weapons delivery systems, these small improvements would be worth the increased costs.
Actually, Fox-7 is slowly coming into wider use. The US military has likely already employed it in the form of propellent compositions, although this has not openly been made public knowledge. The Indian military has been testing Cl-20 based bombs. Cl-20 compositions have not shown good sensitivity to performance trade-offs relative to the HMX compositions currently in use. The increased sensitivity of Cl-20 is more than the increased power. Considering HMX is itself made into less sensitive compositions for improved safety, it does not make much sense to substitute it with Cl-20.
Much research is currently being done into incorporating boron and aluminum nano-powders into explosive compositions. These compositions have a fairly good chance of becoming widespread within the next decade.
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