【摘要】 以RDX为核心物质、NC为最外层、高分子键合剂LBA-201为中间层,利用层层组装(LBL)技术制备了NC-BA-RDX包覆球。实验研究了真空度和搅拌速度对包覆效果、包覆球假密度和粒度的影响,利用扫描电镜(SEM)、透射电镜(TEM)和DSC热分析对包覆球进行观察和分析,并测试了推进剂的力学性能。结果表明,层层组装后得到样品基本呈球形,粒径分布均匀,结构致密,流散性好;采用缓慢升高真空度和温度的方法驱除溶剂得到效果较好的包覆球,实验得到适宜的驱溶时间为20~25 min;搅拌速度从700 r/min增加至2 000 r/min时,包覆球的中位径d50从386.7μm减小至18.4μm,分布宽度(SPAN)值从0.334减小至0.107,实验得到的适宜搅拌速度为1 500~1 800 r/min;包覆球的融化吸热峰强度明显减弱,峰温降低1.7℃,同时分解放热峰温升高4℃,分解热(ΔH)减少142 J/g。推进剂低温(-40℃)延伸率提高111.9%,高温(50℃)延伸率提高51.3%,高低温最大抗拉强度分别提高0.62 MPa和3.24 MPa。更多还原

【Abstract】 Taking RDX as core material,NC as outside layer and LBA-201 bonding agent as middle layer,the NC-BA-RDX coating ball particles were prepared by layer-to-layer assembly technique.The effects of the vacuum degree and stirring speed on the shape,cubic density and size of the spheric particles were investigated by experiments.The coating ball particles were observed and analyzed by means of SEM,TEM and DSC,and the mechanical properties of the propellant were measured.The results show that the samples prepared by the technique present spherical shape with uniform particle sizes,dense structure and excellent fluidity.The better coating ball particles can be obtained by slowly increasing vacuum degree and temperature during the process of taking out solvent,and the optimum time of taking out solvent is 20~25 min.When stirring speed increases from 700 r/min to 2 000 r/min,the medium diameter(d50) of ball particles decreases from 386.7 μm to 18.4 μm,and the SPAN value decreases from 0.334 to 0.107.The suitable stirring speed is 1 500~1 800 r/min.The intensity of melt endotherm peak obviously weakens and the peak temperature decreases by 1.7 ℃.Meanwhile,thermal decomposition peak temperature increases by 4 ℃,and the exothermic enthalpy reduces by 142 J/g.The elongation of CMDB propellant with NC-BA-RDX increases by 111.9% at low temperature(-40 ℃) and 51.3% at high temperature(50 ℃).The maximum tensile strength increases by 0.62 MPa at high temperature and 3.24 MPa at low temperature.更多还原