Investigation into the interaction of Dantocol in polymer bonded explosives and bonding agent development

Author: Christopher Williams

  • Thesis download: available for open access on 28 Nov 2018.

Williams, Christopher, 2015 Investigation into the interaction of Dantocol in polymer bonded explosives and bonding agent development, Flinders University, School of Chemical and Physical Sciences

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Abstract

The call for increased safety in explosive ordnance has driven the requirement for improved design of Insensitive Munitions (IM). Cast-cured Polymer Bonded Explosives (PBXs) are often used as an approach to achieving IM compliance. Incorporation of bonding agents is often employed to improve adhesion between particulates and the binder system, however the exact mechanism by which this occurs is poorly understood. In the absence of an appropriate bonding agent, the PBX system is susceptible to mechanical failure via dewetting. This degradative process occurs when the adhesion between filler and binder is poor, causing failure under stress and allowing the binder to break free or ‘dewet’ from the filler surface. One of the forerunners in bonding agent technology for nitramine-based composites is the Hydantoin derivative 1,3-bis(2-hydroxyethyl)-5,5-dimethylhydantoin, known also as Dantocol. This promotes successful interaction between the filler and binder within polymer composites. Investigations revealed non-polar binder matrices applied in this process enable polar Dantocol molecules to adsorb onto the nitramine filler via secondary bonding. Subsequent reaction with the binder system produces primary bonds involving the diisocyanate curative. This reacts with free hydroxyl groups to form urethane linkages, facilitating integration of Dantocol within the binder matrix. The strength of these bonds dictates the mechanical properties of respective systems, through prevention of deformation mechanisms. Knowledge of surface characteristics and interacting mechanisms was consequently applied to the design of novel bonding agents. Development of bonding agents focussed on improving mechanical properties of PBXs, with flow-on benefits for explosive ordnance. These advances have the potential to eliminate conjecture regarding the selection of bonding agents and provides viable alternatives for inclusion in cast-cured composite energetic materials.

Keywords: Dantocol, bonding agent, polymer bonded explosive, RDX
Subject: Chemistry thesis

Thesis type: Doctor of Philosophy
Completed: 2015
School: School of Chemical and Physical Sciences
Supervisor: Assoc Prof Stewart Walker