ABSTRACT

This research evaluates the feasibility of replacing diphenylamine (DPA) with the natural product curcumin as a stabilizer in samples of nitrocellulose-based (NC-based) propellants. The stability analysis was performed using heat flow calorimetry, as described in STANAG-4582, as well as the most traditional stability testing protocols: the German test, Bergmann–Junk test, and the Storage test. Ballistic parameters were evaluated using a closed vessel ballistic test and samples underwent Scanning Electron Microscopy (SEM). Also, the Pressure Vacuum Stability Test (PVST), Differential Scanning Calorimetry (DSC), and Isothermal Thermogravimetry (TG) to evaluate the homogeneity, stability, and compatibility with NC were performed. The ballistic parameters were evaluated using a closed vessel ballistic test. All samples of propellants stabilized with curcumin passed the stability test criteria performed in this research, with better scores than the propellant sample stabilized with DPA, which was used as a reference. However, the estimation of ballistic parameters indicated that the deflagration of the propellant stabilized with curcumin exhibits some delay when compared to the reference sample, which can be easily overcome by adjusting the propellant grain dimensions, especially the thickness. Finally, an HPLC analysis method was developed to identify and characterize this new Single-Based (SB) propellant stabilizer. This method was shown to be effective, fast, accurate, and adequate to comply with the stability criteria proposed by the AOP-48 standard, especially because of the depletion of the stabilizer concentration after artificial aging. We believe that our results are promising and support the proposal that curcumin can replace DPA as a stabilizer for SB propellants.

摘要

本研究评估了用天然产物姜黄素代替二苯胺 (DPA) 作为硝化纤维素基 (NC) 推进剂样品中的稳定剂的可行性。稳定性分析使用热流量热法进行，如 STANAG-4582 中所述，以及最传统的稳定性测试协议：德国测试、Bergmann-Junk 测试和存储测试。使用密闭容器弹道测试评估弹道参数，并对样品进行扫描电子显微镜 (SEM)。此外，还进行了压力真空稳定性测试 (PVST)、差示扫描量热法 (DSC) 和等温热重法 (TG)，以评估均质性、稳定性和与 NC 的相容性。使用封闭容器弹道测试评估弹道参数。所有用姜黄素稳定的推进剂样品均通过了本研究中进行的稳定性测试标准，其得分高于作为参考的用 DPA 稳定的推进剂样品。然而，弹道参数的估计表明，与参考样品相比，用姜黄素稳定的推进剂的爆燃表现出一些延迟，这可以通过调整推进剂颗粒尺寸，特别是厚度来轻松克服。最后，开发了一种 HPLC 分析方法来识别和表征这种新的单基 (SB) 推进剂稳定剂。该方法被证明是有效的、快速的、准确的，并且足以符合 AOP-48 标准提出的稳定性标准，特别是因为人工老化后稳定剂浓度的消耗。