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Fuel or oxidant composites were trapped in the holes of poly(azide glycidyl ether) (GAP) gel skeleton network on nano-scale, which could effectively increase the contact area, decrease the transport distance, and make the energy release more close to the ideal state to achieve the maximum power of energetic materials. In this study, GAP gels with three dimensional nano-network structures were prepared by sol-gel method using GAP as precursors and hexamethylene diisocyanate (HDI) as curing agent. The obtained gels were well characterized by Brunauer-Emmett-Teller (BET).The results showed that the specific surface area and dominant pore size were about 41.78 m 2 /g and 5~30 nm, respectively. Hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) could be crystallized in the pore of GAP gel skeleton, so RDX/GAP nanocomposite materials were prepared by solute crystallization in combination with a modified drying technology. The average grain size of RDX in GAP network was 20~46 nm. With the increase of the loadings of RDX, the specific surface area of GAP/RDX nano-composite materials decreased, and the thermal decomposition temperature of RDX in RDX/GAP nanocomposite materials decreased by 33~37°C. The decomposition heat and explosion heat of RDX(40 wt%)/GAP nanocomposite materials were higher by over 13.9 and 19.3 % than those of RDX(40 wt%)/GAP physical blend materials, respectively. Furthermore, the sensitivity of RDX(40 wt%)/GAP nano-composite materials was lower than that of physical blend materials according to the results from our impact sensitivity test.

1,hexane type compounds (DABHCs) were found as promising liquid hypergolic compounds. The synthesis process and purification of DABHCs, 1,5-diazabicyclo[3.1.0]hexane (DABH), 6-methyl-1,5-diazabicyclo[3.1.0]hexane (MDABH), 6-ethyl-1,5diazabicyclo[3.1.0]hexane (EDABH), and 6,6-dimethyl-1,5diazabicyclo[3.1.0]hexane (DDABH) were optimized. The densities of DABHCs were over 1.0 g/mL, and the viscosities of DABHCs were about 2.40−2.63 mPa•s. The boiling points of DABHCs exhibited that they were less volatile, and the freezing points of DABHCs varied considerably for different alkylation. The LD 50 predicted values of DABHCs were within 1605.62−4865.43 mg/kg, which demonstrated that DABHCs were grade IV, slightly poisonous, or grade V, nontoxic, compounds according to the Globally Harmonized System of Classification and Labeling of Chemicals (GHS). In addition, the heats of formation of DABHCs were calculated as 129.2−276.2 kJ/mol, higher than those of monomethyl hydrazine, unsymmetrical dimethyl hydrazine, and hydrazine. The ignition delay time of DABH with nitrogen tetroxide was 1 ms, and the ignition delay times of other alkyl substituted DABHCs were 4−11 ms, which indicated the promising application of DABHCs as hypergolic propellants.