Abonnement à la biblothèque: Guest
Portail numérique Bibliothèque numérique eBooks Revues Références et comptes rendus Collections
International Journal of Energetic Materials and Chemical Propulsion
ESCI SJR: 0.149 SNIP: 0.16 CiteScore™: 0.29

ISSN Imprimer: 2150-766X
ISSN En ligne: 2150-7678

International Journal of Energetic Materials and Chemical Propulsion

DOI: 10.1615/IntJEnergeticMaterialsChemProp.2018021264
pages 367-382

SENSITIVITY OF POLYMER-BONDED EXPLOSIVES FROM MOLECULAR MODELING DATA

David Brochu
DND
Hakima Abou-Rachid
Defence Research and Development Canada−Valcartier Research Centre, Government of Canada, 2459 de la Bravoure Road, Québec, QC, Canada, G3J 1X5
Armand Soldera
Département de Chimie, Centre Québécois sur les Matériaux Fonctionnels, Faculté des Sciences, Université de Sherbrooke, Québec, Canada J1K 2R1
Josee Brisson
Département de Chimie, CERMA (Centre de Recherche sur les Matériaux Avancés) and CQMF (Centre Québécois sur les Matériaux Fonctionnels), Faculté des Sciences et de Génie, Université Laval, Québec, Canada G1V 0A6

RÉSUMÉ

Sensitive energetic materials are an issue for military and civilian applications. To prevent undesired explosions, sensitive energetic materials are embedded in a protective polymer, resulting in polymer-bonded explosives (PBX). The appropriate polymer will absorb part of the energy caused by stimuli such as shock, impact, friction, and heat, thus decreasing sensitivity. To investigate how an appropriate polymer absorbs energy, three PBX models were simulated using molecular dynamics. The COMPASS force field implemented in the Materials Studio software was used. Molecular dynamics simulations were performed for three RDX-based formulations in which a single polymer chain (HTPB, Estane, or EVA) was placed at the boundary surface of an RDX crystal. Simulations were carried out at high temperature (700 K) and high pressure (15 GPa). The resulting models were analyzed in terms of potential energy increase, energy distribution, and values of the different potential energy contributions for RDX/HTPB, RDX/Estane, and RDX/EVA. The polymer binders HTPB, Estane, and EVA in such PBX formulations absorbed between 24% and 31% of internal energy, respectively, thereby making less sensitive PBXs formulations than pure RDX. This percentage is proposed as an indicator key for experimentalists to determine the most efficient polymer that can be used, for a given explosive, to minimize munition sensitivity. A clear correlation is established between the calculated absorption of internal energy by polymers and experimental sensitivity values for the three formulations studied under extreme experimental conditions. This approach may be applied to other new formulations prior to testing them in laboratories.