PBT钝感高能推进剂高温力学性能调节技术研究

Study on Adjustment Technology for High Temperature Mechanical Properties of PBT Insensitive High Energy Propellant

为了改善PBT类型钝感高能推进剂的高温力学性能,分析了推进剂高温力学性能的影响因素,研究了中性键合剂粒度、用量以及固化网络交联分子量对高温性能的影响,并进一步考察了组合键合剂技术(中性键合剂+醇胺键合剂)在三种不同燃速(高燃速、中燃速、低燃速)配方中的使用效果。研究表明:(1)醇胺键合剂对HMX粒子表面缺乏有效的化学键合,HMX能部分溶解在极性增塑剂A3中,形成软界面层,这两点使得试样拉伸过程中HMX的表面容易"脱湿",影响高温力学性能。(2)通过调整固化参数和交联剂用量,控制交联分子量,优化固化网络,并结合组合键合剂技术,能获得高、低、常温力学性能优良的PBT钝感高能推进剂配方,当NPBA的用量为0.08%～0.10%,交联分子量Mc达到8000～10000时,推进剂的高温抗拉强度大于550kPa,伸长率达到40%以上。

For PBT insensitive high energy propellant, factors that influence high temperature mechanical properties of the propellant were analyzed. The effects of particle size and content of neutral polymeric bonding agent as well as molecular weight between crosslinking points in the curing network on the high temperature properties were studied. The performance of the propellant using multi-bonding technology （neutral polymeric bonding agent＋ alcohol amine bonding agent） in three different burning rate formulations （high burning rate, medium burning rate, low burning rate） were further investigated. The results showed that： （1）Alcohol amine binding agent is lack of effective chemical bonding to the surface of HMX particles, HMX can be partially dissolved in a polar plasticizer A3 to form a soft interface layer, these two points make the surface of HMX easily ＂dewetting＂ during the stretching processes, affecting its high temperature mechanical properties. （2）The curing network was optimized by adjusting the curing parameters, the amount of crosslinker and the molecular weight between crosslinking points. With the combination of the multi-bonding technology, the PBT insensitive high energy propellant with excellent mechanical properties at high temperature, low temperature and room temperature were obtained. When the amount of NPBA is 0.08%-0.10% and Mc reaches 8000-10000, the high temperature tensile strength of the propellant is more than 550kPa, the elongation is over 40%.