tailieunhanh - Thermal decomposition and shelf-life of PETN and PBX based on PETN using thermal methods

The experimental results demonstrate that the nitrocellulose (NC) binder accelerated the thermal decomposition process and hence reduced the thermal stability and shelf-life of the PBX compared to PETN, whereas the polystyrene (PS) binder seems to play no negative influence on the thermal stability of PETN in the PBX composition. | Vietnam Journal of Science and Technology 56 (3) (2018) 303-311 DOI: THERMAL DECOMPOSITION AND SHELF-LIFE OF PETN AND PBX BASED ON PETN USING THERMAL METHODS Nguyen Trung Toan1, *, Phan Duc Nhan1, Vo Hoang Phuong2 1 Military Technical Academy, 236 Hoang Quoc Viet, Ha Noi, Viet Nam 2 Institute of Military Science and Technology, 17 Hoang Sam, Ha Noi, Viet Nam * Email: trungtoanktqs@ Received: 31 January 2018; Accepted for publication: 28 April 2018 Abstract. Binders exert a strong influence on the safety and explosion properties of polymerbonded explosives (PBX) based on pentaerythritol tetranitrate (PETN). In this paper, the thermal behavior and decomposition kinetics of two PBX samples formulated from PETN were evaluated along with a PETN sample using various thermal techniques and analytical methods. The experimental results demonstrate that the nitrocellulose (NC) binder accelerated the thermal decomposition process and hence reduced the thermal stability and shelf-life of the PBX compared to PETN, whereas the polystyrene (PS) binder seems to play no negative influence on the thermal stability of PETN in the PBX composition. Keywords: kinetics, PBX, PETN, shelf-life, thermal decomposition. Classification numbers: ; ; . 1. INTRODUCTION Pentaerythritol tetranitrate (C5H8N4O12, PETN), which is a nitrate ester explosive, is widely used for military and civilian purposes because of its high energy density properties [1-3]. However, PETN is highly sensitive to mechanical pulses such as impact and friction, and resistant to compression. To overcome these problems, one of the methods is mixing PETN with some selected polymeric binders, commonly referred to as polymer-bonded explosive (PBX) [1, 3, 4]. The polymeric binder coating, that binds the explosive granules, can absorb impact impulse, reducing the sensitivity of explosives to mechanical shocks. In addition, it can also improve the mechanical and chemical