Synthesis of 3D Porous Network Nanostructure of Nitrated Bacterial Cellulose Gel with Eminent Heat-Release, Thermal Decomposition Behaviour and Mechanism

In this study, a novel three-dimensional (3D) porous cross-link network structure of nitrated bacterial cellulose (NBC) nano-gel, as an energetic gel matrix for fabrication of nanocomposite energetic materials, (nEMs) was synthesized by sol-gel synthetic and the freeze-drying technology. The analysis results revealed that the unique network structure with abundant of nano-porous, which made the thermal behaviour of the NBC gel different from that of raw NBC. The thermal decomposition kinetic and mechanism of the NBC gel indicated that the exothermic peak temperature of the gel matrix decreased at low concentration, and the activation energy (E-a) of the gel(0.5) (150000 J . mol(-1)) was much lower than that of raw NBC (223510 J . mol(-1)). However, the decomposition kinetic parameters of this study were not enough to illustrate the thermal properties, and which needs more effort to study them and complete. Furthermore, the initial reaction of gel decomposition was the splitting of urethane bond, and then the scission of -O-NO2 bonds happened, and the macromolecular chains' breakage site of gel first occurred at -C-O-C- in the ring. After then, the chains of NBC break at -C-O-C- between the rings; notably, the heat-release of gel was several times than that of raw NBC, which was liberated during the process of thermal decomposition. This promising research may provide potential application in preparing binder-based nEMs and the basic theory of thermo-analysis used in propellants and explosives.