Electrospray Deposition of Energetic Polymer Nanocomposites with High Mass Particle Loadings: A Prelude to 3D Printing of Rocket Motors

Abstract

One of the challenges in the use of energetic nanoparticles within a polymer matrix is the difficulty in processing by traditional mixing methods. In this paper, electrospray deposition is employed to create high loadings of aluminum nanoparticles (Al-NPs) in polyvinylidene fluoride (PVDF) reactive composite films. The deposited films containing up to 50 wt% Al are found to be crack free and mechanically flexible. Thermochemical behavior characterized by thermogravimetric (TG) and differential scanning calorimetry (DSC) analysis shows that the addition of Al-NPs sharply reduces the onset decomposition temperature due to a pre-ignition reaction occurring in the film. The combustion propagation velocity in air at three different mass loading of Al-NPs shows burning rates of 5, 16, and 23 cm s À 1 for loadings of 16.7,30, The results suggest electrospray deposition as a direct approach to make bulk polymer composites containing high metal particle mass loading and may be a prelude to 3D printing of rocket motors.

Physiochemical Characterization of Iodine (V) Oxide Part II: Morphology and Crystal Structure of Particulate Films

“…Etching can be used to prepare nanostructured substrates (fuel) into which an oxidizer can be deposited [23]. Suspension of particulates coupled with ink-jet writing has also been used to fabricate energetic films [24][25][26]. In general, these and other sophisticated methods produce an intermixed material with a range of domain sizes and morphology, each coming with a range of advantageous and detrimental properties for a given application.…”

Direct Deposit of Highly Reactive Bi(IO3)3‐ Polyvinylidene Fluoride Biocidal Energetic Composite and its Reactive Properties

“…[21] In a typical experiment, 141.2 mg of Bi(IO 3 ) 3 nanoparticles, 107.9 mg Al-NPs, 200 mg PVDF, and 4.5 mg AP was dissolved in 4 mL DMF. In our previous work, we find that a small quantity of AP in the precursor can significantly improve the morphology and mechanical property of the films.…”

“…Our previous research [21] showed that Al/ PVDF could be fabricated in a direct write mode to create 3D printed propellant. In this study, we have so far shown that Bi(IO 3 ) 3 when reacting with Al can generate both heat and biocidal iodine.…”

“…This approach enables the eventual ability to make graded and laminate structure as we have described previously, [21,30] at high particle loadings. This approach enables the eventual ability to make graded and laminate structure as we have described previously, [21,30] at high particle loadings.…”

“…[21] In addition, a film structure is ideal for evaluation of mechanical and combustion properties due to a well-defined geometry and architecture. In this case, we build on our prior work on 3D printing of propellants.…”