[a] 1IntroductionAs heet explosivei saflexible plastic-bonded explosive (PBX) [1][2][3][4][5],i nw hich high energy materials (HEMs), like 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX), (3-nitrooxy-2,2-bis-bis-(nitrooxymethyl)propyl) nitrate (PETN), are uniformly dispersed in ap olymeric matrixa nd form af lexible composite material that can be rolled/cut into sheet form [6,7].P olymers provide continuumf or the dispersiono fH EMs and play avital role in deciding the structuralintegrity andflexibility as well as the sensitivity of sheet explosivec ompositions. Sheet explosives find wide application in the civilian field as well as the military field. In addition to metal cutting, demolition, and welding [8,9],s heet explosives are used as component of explosive reactive armors (ERA) [10][11][12][13].A nE RA is made of sheet explosive, which is sandwiched betweent wo metal platesa nd offers effective protection to armored vehicles, includingt anks,a gainst attacks by projectiles and warheads based on the shaped charge concept. Sensitives heet explosives are being pursuedt o counter threats of kinetic energy projectiles based on metallic penetrators.Natural rubber/crepe rubber is generally used as the binder for sheet explosive formulations [14].H owever,t his sheet explosive has limited shelf life because natural rubber tends to undergo deterioration due to oxidation of the isoprene unit durings torage [15].H ydroxyl-terminated polybutadiene (HTPB)-based sheet explosives were also reported [16].T he major disadvantages of HTPB-based sheet explosive are that the maximum loading capacity of energetic materials in HTPB is up to 85 %a nd the poor mechanical properties. Thus, polymers like thermoplastic elastomers (TPEs), e.g.,e thylene vinyl acetate (EVA) (copolymers of ethylene and vinyl acetate), Estanea nd HyTemp-4454 (copolymer ethyl and butyla crylate) have founda pplication as binders in sheete xplosive formulations [ 14,17,18].T he maximumv elocityo fd etonation( VOD) was reported as 7200 ms À1 [18]. In view of the above and our continuedr esearch and development work in the area of sheet explosives, we report herewith the development of RDX-baseds heet explosive formulations. Ah ybrid binder system comprising of linear thermoplastic polyurethane and fluoroelastomer( Viton) was selected to achieve the desired sensitivityw ithout the penaltyo nm echanical properties whiler etaining long shelf life. The authors have claimedapatent [19] of these formulations with the Indian patent office. The sensitivity,p erformance and thermal data obtained for sheet explosive formulationsh ave been compared with the naturalr ubberbased sheete xplosive under similar experimentalc onditions. Thermal analysis study of high energy materials is im- Abstract:Aplastic-bonded explosive (PBX) in the form of as heet was formulated comprising of 1,3,5-trinitroperhydro-1,3,5-triazine (RDX) and an hybrid binder system containing alinear thermoplastic polyurethane and afluoroelastomer...