Making progress towards promising energetic cellulosic microcrystals developed from alternative lignocellulosic biomasses

ABSTRACT This study reported the valorization of various alternative lignocellulosic feedstocks including giant reed (GR), palm fronds (PF) and esparto grass (EG) for the development of promising nitrated structurally modified cellulosic biopolymers (NNCs). The extracted nanostructured cellulose precursors and their nitrated derivatives were analyzed for their physicochemical properties, chemical structure, crystallinity and thermal stability. Experimental findings confirmed the successful formation of the desired energetic NNCs polymers with increased densities (1.698–1.711 g/cm3) and high nitrogen contents (13.10–13.26%) followed the order NNC-EG>NNC-PF>NNC-GR, which are greater than those of the commonly used nitrocellulose (1.650–1.670 g/cm3 and 12.50–12.70%). Furthermore, isoconversional integral models (TAS, it-KAS and VYA/CE) were exploited based on non-isothermal DSC data to investigate their thermal decomposition kinetics. The predicted kinetic parameters displayed that the synthesized energy-rich NNCs presented close values of Arrhenius parameters within the range of 156 ≤ Eα (kJ/mol) ≤163 and 14.7 ≤ Log(A(s−1) ≤ 15.6, and decomposed following diverse reaction mechanisms. Consequently, the explored lignocellulosic biomasses could be considered as valuable alternative non-woody resources for the production of advanced high-energy dense cellulosic biopolymers for potential application in the next generation of solid propellant formulations and composite explosives.