Properties of CMDB Propellant Containing High-Nitrogen Compound BTATz

The samples for the composite modified double-base(CMDB) propellant containing the high-nitrogen compound 3,6-bis(1H-1,2,3,4-tetrazol-5-yl-amino)-1,2,4,5-tetrazine(BTATz) using as a substitute of hexogen(RDX) were prepared and the burning rates were measured,the characteristics of the thermal decomposition and combustion were investigated systematically by the technologies of TG-DTG,PDSC,the single-shot flame photo,the temperature distribution of combustion,and the structure and element content of quenched surface.The results show that the energy property parameters of the original control DB propellant will be decreased with nitrocellulose(NC) and nitroglycerine(NG) of the propellant being substituted by BTATz with a low oxygen balance(OB),so,the content of BTATz in the propellant formulation should be appropriate.BTATz-CMDB propellants are suitable to be prepared by a solventless CMDB propellant extrusion technique.BTATz has a highlight potential to increase the burning rates of the propellants,especially with the catalyst system(the mixture of lead phthalate,copper adipate and carbon black) which has a positive effect on the main exothermal reaction of the propellant.The flame of BTATz-CMDB propellant has the general characteristic of the flame of the double-base propellant,but BTATz makes it feasible for the presence of the diffused flame clusters as without such a melting process as RDX,makes the combustion surface of the propellant look like loosing coral reef rather than melting state,and the flame becomes much strong.With the pressure increasing,the amount of the activation spots increases where the diffused flame clusters occur,the dark zone becomes very thin,the heat feedback on the combustion surface coming from the flame zone is increased,and the burning rate is accelerated.The catalyst system can affect slightly on the gas phase of the combustion reaction,but it can enhance the exothermic reaction close to the condensed phase and its surface,and change the structure of the combustion surface.During the combustion process of the propellant,the fresh catalyst will be collected on the combustion surface,catalyzing the decomposition and combustion,improving the burning rates of the propellants.