Killer Number One: Explosive Crystal

Penetration test of explosives: on the right for a 30-gram HMX charge, on the left for the same CL-20 charge

The search for increasingly powerful explosives has been going on for centuries. Traditional gunpowder has long since left the stage, but the advent of compact robotic warfare tools, including drones, only stimulate new searches. The smaller size and mass of warheads will retain the deadly power of their larger predecessors only thanks to the latest achievements of chemists.

The ideal explosive is a balance between maximum explosive power and maximum stability during storage and transportation. This is also the maximum density of chemical energy, the minimum price in production and, preferably, environmental safety. To achieve all this is not easy, therefore, for the development in this field, the already proven formulas - TNT, hexogen, pentrite, hexanitrostilbene, etc. - are usually taken and they try to improve one of the desired characteristics without harming the others. Completely new compounds appear extremely rarely.

An interesting exception to this rule may be hexanitrohexaazaisowurtzitane (CL-20), ready to enter the elite list of popular explosives. First synthesized in California in 1986 (hence CL in its abbreviated name), it contains chemical energy in the most dense form. So far, only a few companies have been producing it industrially at a price of more than $ 1, 300 per kilogram, however, when switching to large-scale synthesis, the cost may fall, according to experts, 5-10 times.

Today, one of the most effective military explosives is octogen, which is used in plastic charges and the price of which is about $ 100 per kilogram. However, the CL-20 (take a look at the illustration on the left) shows a markedly greater power: in tests for penetrating through steel blocks it is 40% more efficient. This power is provided by a higher detonation velocity (9660 m / s against 9100 m / s) and a higher density of the substance (2.04 g / cm3 against 1.91).

Such incredible power allows us to believe that the CL-20 will be especially useful in use with compact combat systems, such as modern drones. However, it is dangerously sensitive to shocks and shocks — roughly like pentrite, the compound most sensitive to them from all explosives used. Initially, it was assumed that CL-20 will be able to be used together with a plastic binding component (in a 9: 1 ratio), although at the same time, explosive force also decreases along with a reduction in the danger of detonation.

In short, the history of the CL-20, which began in the 1980s, so far has not turned out very well. However, chemists do not stop experimenting with him. One of them was the American professor Adam Matzger (Adam Matzger), under the guidance of which the substance, it seems, was able to improve to an acceptable form. The authors tried to change his form, not structure.

It is worth saying here that if you take a mixture of crystals of two different substances, a separate molecule of each crystal is surrounded by neighbors like her. The properties of the mixture turn out to be a cross between the properties of one and the other substance in its pure form. Instead, Matzger and colleagues tried a method of co-crystallization from a common solution - they managed to obtain molecular crystals containing both substances simultaneously: two molecules of CL-20 account for one octogen molecule.

After studying the properties of this compound, scientists found that its detonation speed is 9480 m / s - that is, approximately in the middle between the speeds for pure CL-20 and HMX. But stability is almost as high as that of pure octogen (according to the authors, due to the formation of additional hydrogen bonds between the two types of molecules, which stabilize the sensitive CL-20 molecule). In addition, the crystal density is about 20% higher than that of HMX, which makes it even more efficient. In other words, such a crystal is a significant improvement in comparison with octogen and a very promising candidate for the role of the new "best explosive in the world."

According to the publication of Gizmag.Com

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