Biomimetic modification strategy of nitrate glycerol ether cellulose with polydopamine and its thermal decomposition behavior

Nitrate glycerol ether cellulose (NGEC) is a potential cellulose substitute for the substrate of gun propellants in the future, but interfacial compatibility with high energy solid filler has remained an ongoing challenge. In this study, NGEC, modified with polydopamine (PDA), were prepared with various reaction time, to obtain composite energetic cellulose core-shell materials with improved hydrophilic and adiabatic safety by combining advantage of self-polymerization of dopamine (DA). The composition, distribution, and hydrophilicity of the molecular groups of the composite energetic cellulose were evaluated, as well as the thermodynamic behavior and safety properties in the adiabatic environment. Results demonstrated that the structure of NGEC remained unchanged when PDA formed dense nanofilm on the surface of NGEC, and the introduction of hydroxyl group in PDA significantly improved the hydrophilicity of NGEC by WCA analysis. Most notably, according to DSC and TGA data, after applying PDA coating, both the activation energy (Ea) and weight loss ratio (Wr) of high-energy cellulose showed a slight decrease. Specifically, the Ea of NGEC@PDA-6 h was very similar to that of NGEC and showed the lowest Wr. The PDA coating might also substantially increase the initial temperature and pressure of the adiabatic decomposition of the NGEC by the ARC results. In summary, without altering the intrinsic properties of the NGEC, PDA could increase the safety properties of the adiabatic environment, providing a method for hydrophilic modification of the energetic cellulose surfaces.

Automated summary

In this study, composite energetic cellulose core-shell materials with improved hydrophilic and adiabatic safety were successfully prepared by modifying nitrate glycerol ether cellulose (NGEC) with polydopamine (PDA). The PDA coating did not alter the structure of NGEC, but significantly improved its hydrophilicity.