Surface Modification Technology Of High-plasticizer-concentration Gun Propellant

To solve the surface deterring technology problem of azide nitramine gun propellant (DA propellant) with high plasticizer concentration,we originally introduced 1,3-dipolar cycloaddition into deterring system.Two kinds of deterrent samples were synthesized and characterized,and then used to deter DA propellant separated.Their deterring effect and long-term-storage stability was characterized.Following are the conclusions of the study.(1) Dipropargyl adipate(DPAP) and tripropargyl trimesate(TPTM) were prepared separated from adipic acid and trimesic acid,via acyl chlorination with thionyl chloride, propargyl alcohol condensation,as samples of SD and ST.They were characterized with FTIR,~1H-NMR,and MS to prove they were target products,however,they were not pure. Side reactions maybe take place when they were purified.(2) The reactivity between SD or ST and DIANP or DA propellant was characterized with DSC.As a result,both of two samples could react with DIANP from lower temperature(60℃),besides,they increase the decomposition temperature of DIANP,so they could do as deterrents.Both SD and ST could solve in DA propellant very well,and raise its decomposition temperature,while ST does better than SD in this aspect.The effect of them to the initial decomposition temperature of DA propellant was not obtained so far. The more important is that some product of the decomposition of mixture of ST and SD after 200℃show endothermic peak in DSC after 280℃,which is very interesting in surface deterring.(3) DA propellant was deterred in rotary drum with SD and ST as deterrents,and its burning property was characterized with closed bomb.The conclusions are these:ST show better deterring effect for DA propellant.Anti-mobility of deterred propellants was characterized by accelerating aging at 85℃,and then characterized with closed bomb, indicating that DA propellant deterred by ST showed stable burning properties.This verified the solution stated above.However,because of too high temperature of accelerating aging,mass lost of propellant took place,and total energy of propellant decrease.Further study of deterring effect of ST to DA propellant should be done to make sure if it satisfies expect of the project.