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In this study, microcrystalline cellulose nitrate (MCCN) as energetic polymer is successfully obtained from Posidonia oceanica brown algae (POBA). Fourier transform infrared spectroscopy (FTIR) results show alterations in the intensities of some absorption bands, suggesting a significant difference in the chemical structure between microcrystalline cellulose and the emergent MCCN samples. X‐ray diffraction (XRD) measurements indicate that MCCNs are more crystalline than conventional nitrocellulose (NC). According to scanning electron microscopy (SEM), both NC and MCCN reveal a compact structure and a rough surface. Differential scanning calorimetry (DSC) displays that the thermal degradation of MCCNs shifts to lower temperatures compared to the respective NCs. Furthermore, in comparison with NC samples, MCCN samples exhibit high density, high nitrogen content, low viscosity‐average molecular weight, and good thermal stability. On the other hand, kinetic modeling based on DSC data is carried out by isoconversional integral methods to determine Arrhenius parameters and the decomposition mechanisms. It is found that MCCNs present lower activation energies than conventional NCs with a decrease of ≈6%. Finally, this work opens a new pathway to prepare MCCN from POBA, and it is expected to have applications in several areas such as propellants, energetic binders, and gas generators.

In this paper, the compatibility of nitrocellulose (NC) with some aniline‐based stabilizers was studied in order to detect any interaction between these materials. Both thermal techniques [differential scanning calorimetry (DSC) and vacuum stability test (VST)], and supplementary non‐thermal techniques [Fourier transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD) and densimetry] were used. The thermal and non‐thermal measurements showed that NC was highly compatible with N‐(2‐methoxyethyl)‐p‐nitroaniline (MENA) and diphenylamine (DPA), while a degree of incompatibility is indicated for N‐(2‐acetoxymethyl)‐p‐nitroaniline (ANA). The compatibility of the different mixtures was further probed by the kinetic investigation, and the activation energy and the pre‐exponential factors were computed. A detailed discussion and comparison of the compatibility results from all the methods are made.

In the present work, a green synthesis of copper oxide nanoparticles (CuO NPs) has been performed through a precipitation method using three different copper precursors and sylvestrys leaf extract as a capping agent. Morphology and structure of the obtained CuO NPs were confirmed by X‐ray diffraction (XRD), ultraviolet‐visible (UV/Vis), Fourier transform infrared (FT‐IR) and Raman spectroscopy, as well as scanning electron microscopy (SEM). Moreover, their thermal behavior and catalytic performance were studied using thermogravimetry (TG) and differential scanning calorimetry (DSC). Four isoconversional kinetic methods have been applied to the DSC data obtained at different heating rates in order to determine the kinetic triplets. The results showed that the introduction of CuO NPs has noticeably lowered the thermal decomposition temperature by 91.7, 89.9, and 83.0 °C, and increased the exothermic enthalpy by 1053, 832, and 962 J·g–1 for AP‐CuO‐S, AP‐CuO‐N, and AP‐CuO‐Cl, respectively. Furthermore, CuO NPs were found to reduce the activation energy of AP decomposition. Besides that, ammonium perchlorate decomposes following different reaction models g(α), depending on the decomposition stage and the addition of CuO NPs. These results indicate further that the green synthesized CuO nanoparticles are promising ballistic modifiers for composite solid propellants.

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