Plastic Bomb

Cotton reacts with nitric acid to form a polymeric explosive material, nitrocellulose. Nitric acid reacts with hexamethylenetetramine, ammonium nitrate, and acetic anhydride to form cyclotrimethylenetrinitramine, a high explosive known as cyclonite, used to make plastic bombs ... 

Note Plastic bomb was also described by A.Stett-bacher in Tages-Anzeiger fur Stadt und Kanton, Zurich, 20 April, 1961... 

Cyclonite is a high explosive and principal constituent of plastic bombs. It is prepared by treating hexamethylenetetramine with nitric acid, ammonium nitrate, and acetic anhydride It is also used as a rat poison. 

Searching a crime scene is a complex process (25), involving poHce, crime scene technicians, and forensic scientists. The procedure requires careful documentation, collection, and preservation of the evidence. Trace evidence (26) in criminal investigations typically consists of hairs (27,28) both natural and synthetic fibers (qv) (29,30), fabrics glass (qv) (31,32) plastics (33) sod plant material budding material such as cement (qv), paint (qv), stucco, wood (qv), etc (34), flammable fluid residues (35,36), eg, in arson investigations explosive residues, eg, from bombings (37,38) (see Explosives and propellents), and so on. 

Warhead Configuration , PATM 1459 (1964) 40) D.K. Armstrong, A Feasibility Study of The Use of Plastic-Bonded Explosives (PBXN-102) In Mk 80 Series Low-Drag Bombs , NOTS TP 3831, NAVWEPS 8755 (1965) 41) S.B. 

Initiation by Light. Neither Deb (quoted in Ref 19, p 111) nor the writer (Ref 47) could produce detonation of PETN exposed to high-intensity light. The writer used PETN cores at 0.8 to 1.5g/cc, with and without small additions of graphite (in attempts to increase light absorbency), in 1 /4 inch ID plastic holders, and exposed them up to around 25microsec to the radiation of Argon flash bombs (T=29000°K). 

RDX may be used alone in pressed charges, although for this purpose tetryl is a more general choice. For shell and bomb fillings it is too sensitive alone to initiation by impact and friction and is either desensitised with wax, or else used like PETN in admixture with TNT. RDX may also be compounded with mineral jelly and similar materials to give a useful plastic explosive. 

To take radio-activity alone. .. perhaps there is no discovery of modern times which has so disorganized the fertile but by no means plastic brain and imagination of the workers in physical science as this bomb which overthrew with a mighty force all current and reputable theories of the constitution of Matter and its inherent quality. It was the assumption that Matter existed alone in the dense ponderable condition, which we have been told by generations of scientists is its main characteristic, that caused them to fabricate the Mechanical Theory of Nature. (550)... 

The major differences between the fluorine and oxygen combustion calorimetry methods arise from the exceptional reactivity and toxicity of fluorine. The substances studied by oxygen combustion calorimetry are normally stable when kept inside a bomb at 298.15 K and under 3 MPa of O2. Oxygen- and moisture-sensitive compounds can also be studied because various types of containers are available to prevent their reaction with O2 prior to ignition. Common examples are glass ampules, which are inert toward the combustion process and, more commonly, Melinex bags or polyethene ampules, which burn cleanly to CO2 and H2O. As carbon dioxide and water are also generated in the combustion of the sample, no extra complexity is introduced in the analysis of the final state of the bomb process by the use of those plastic containers. 

Plastic explosives contain one or more of the explosives listed above, moulded in an inert, flexible binder. Because powders do not readily hold a shape and TNT is the only common melt-castable explosive, most of the explosive powders (RDX, HMX, PETN, 1,3,5-triamino-2,4,6-trinitrobenzene (TATB)) are plasticized to make a mouldable material, for example, C-4, Semtex H, PE4, sheet explosive. A variety of plasticizers are added, but the maximum level is usually 10-15% because most plasticizers are inert and would degrade explosive output. Plastic explosives were originally developed for convenient use in military demolitions but have since been widely used in terrorist bombs. For detection techniques that rely on vapour signatures, such as canine olfaction, it is worth considering that the plasticizer is much more volatile than the explosive component. 

Table 4 gives details of some relevant physical and thermal properties of a range of common explosives that have been encountered in terrorist bombs. It should be noted that DMNB (2,3-dimethyl-2,3-dinitrobutane) is one of the taggants added to plastic explosives under the Montreal Convention on marking of plastic explosives. Dinitrotoluenes are frequently added to blasting gelatine as a minor component and are also found in TNT as a significant impurity. 

Fig. 7.3. a,b Laser-induced time-resolved luminescence spectra of plastic used for road-side bombs covering (a) and dolomite rock (b)... 

About 6 oz of WP (white phosphorus) enclosed in a plastic bag is placed behind the dome and ahead of PT1. When the bomb strikes a target, the fuze functions and sets off... 

Bomb Burster, AN-M13., designed for use (in conjunction with igniter AN-M9) in incendiary bomb AN-M47A4, consists of a plastic tube 0.45-inches in diam, 36.0-in long, provided at each end with a soft brass cup. It is filled with ca 65 g of TNT and has a Tetryl pellet at each end (Ref 51a, P 5-15)... 

Bomb Burster M31 consists of a cylindrical fiber body 1.44-inches in diam 7.0-in long filled with 250 g of Tetryl. One end of the body is closed by a plastic cap, while the other end by a paper disc. This burster is an integral part of nonpersistent gas bombs M125 M125A1, and is installed in the bombs during their manuf (Ref 5 la, p 5-19)... 

When signal hits water, the plastic cover collapses, thus allowing water to force the dye out thru the tail of the bomb. The resulting bright-green spot of dissolved dye on the surface of water permits one to locate the place where the bomb hit the water (Ref 51a, p 5-28)... 

In the M69-WP bomb, 0.4g of the gel contained in the nose of a regular M-63 bomb was replaced with a plastic cap containing white phosphorous. When the gelgas is ejected from the casing, the force of explosion breaks the cap and scatters the WP about the area. The smoke produced by WP obscures objects, makes breathing difficult and hampers fire-fighting... 

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