Evaluation of the compatibility of energetic nitrocellulose/plasticizer blends through molecular dynamics simulation

The compatibility of binders and plasticizers has a significant influence on the properties of polymer-bonded explosives. Molecular dynamics was employed to explore the compatibility between nitrocellulose (NC) with different nitrogen contents and three azido plasticizers by the solubility parameter, mean square displacement, binding energy, radial distribution function (RDF), radius of gyration, and volume distribution. With the increase of nitrogen content, the solubility parameters of NCs decreased and were in good accordance with the reporting results. 1,5-diazido-3-oxapentane (AZDEGDN) had a stronger diffusion ability in NC than that of the other two plasticizers. The introduction of the RDF suggested that the strong interaction between the NC and AZDEGDN mainly came from the hydrogen bonds between hydroxyl groups of NC molecules and the azido in plasticizers. AZDEGDN increased the free volume in NC/AZDEGDN blends, and the mobility of the molecular chains was enhanced, thus the radius of gyration of the NC molecular chains increased. The comprehensive performances demonstrated that AZDEGDN had a strong plasticizing effect on NC because of hydrogen bonds, presenting a potential option for optimizing explosives formulations.