Journal of Hazardous Materials B137 (2006) 1848–1852 Method for preparation of fine TATB (2–5 m) and its evaluation in plastic bonded explosive (PBX) formulations M.B. Talawar, A.P. Agarwal ∗ , M. Anniyappan, G.M. Gore, S.N. Asthana, S. Venugopalan High Energy Materials Research Laboratory, Pune-21, India Received 26 January 2006; received in revised form 9 May 2006; accepted 10 May 2006 Available online 16 May 2006 Abstract There is a need of fine 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) (2–5 m) for various high explosive formulations to achieve desired mechan- ical strength, ease in processing and finally, provide better performance of end product. The reprecipitation method for TATB has been developed using concentrated sulfuric acid as a solvent. The reprecipitation parameters of TATB were optimized to achieve required fine TATB of particle size ∼2–5 m. The characteristic properties of fine TATB thus obtained have been confirmed by FTIR, DSC and TG-FTIR. The spectroscopic and thermal data obtained for fine TATB were compared with standard coarse TATB and found chemically unchanged during particle size reduction. In the present study, the preparation of fine TATB was also attempted using ultrasonication method. The fine (2–5 m) TATB has been introduced to study in the bimodal high explosive formulations. High explosive formulations based on coarse (55 m) and fine TATB (∼2–5 m) with 10% polyurethane were studied. It was observed that properties like bulk density (1.70 g/cm 3 ), mechanical strength/compressed strength (115.9 mg/cm 2 ), %elongation (6.36) were improved for fine TATB in comparison with coarse TATB (∼55 m) alone in high explosive formulations. © 2006 Elsevier B.V. All rights reserved. Keywords: Fine TATB; Preparation; Characterization; PBX formulation 1. Introduction The most important insensitive high explosives (IHEs) for use in modern nuclear warheads is 1,3,5-triamino-2,4,6- trinitrobenzene (TATB), because its resistance to heat and phys- ical shock is greater than that of any other known material of comparable energy [1]. The Department of Defence, U.S., is also studying the possible use of TATB as nuclear stockpile and an insensitive booster material, because even with its safety char- acteristics, a given amount of that explosive has more power than an equivalent volume of 2,4,6-trinitrotoluene (TNT). The high stability of TATB favors its use in military and civil applications where insensitive type explosives are required [2]. In addition to its application as HE, TATB is used to produce the impor- tant intermediate benzenehexamine. Benzenehexamine has been used in the preparation of ferromagnetic organic salts and in the synthesis of new heterocyclic molecules [3]. ∗ Corresponding author. Tel.: +91 20 25869303x2217; fax: +91 20 25869316. E-mail address: anniorganic@rediffmail.com (A.P. Agarwal). In addition to its military uses, TATB has been proposed for use as a reagent in the manufacture of components for liquid crystal computer displays [4]. There is also interest in employing the explosive in the civilian sector for deep oil well explorations, where heat insensitive explosives are required. Other potential applications include the use of TATB as the booster or main charge explosive for down-hole oil perforation at elevated tem- perature surrounding. However, one major problem with the utility of TATB is the resistance to initiation as required. TATB was prepared by amination of 1,3,5-trichloro-2,4,6- trinitrobenzene (TCTNB) in toluene with anhydrous ammonia gas in a pressurized reactor [5]. TATB thus produced has parti- cle size of 50 m or larger and is suitable for most application. However, fine-grained TATB is desirable for ease of initiation. However, there is a need of fine particle TATB (<10 m) for sev- eral high explosive formulations under development at HEMRL to achieve the ease in processing and desired mechanical strength and performance of the end product. Plastic bonded explosive (PBX) 9502 has been formulated as a insensitive high explosive comprised of 95% TATB and 5 wt% Kel-F800 TM binder. Several studies on PBX 9502 have shown significant differences between 0304-3894/$ – see front matter © 2006 Elsevier B.V. All rights reserved. doi:10.1016/j.jhazmat.2006.05.031