为了研究黏结剂对CL-20/FOX-7基PBX性能的影响,分别以Estane、EPDM、ACM、EVA为黏结剂,采用水悬浮法制备了含有不同黏结剂成分的CL-20/FOX-7基高聚物黏结炸药(PBX); 采用场发射扫描电子显微镜(SEM)、激光粒度分析仪、X射线衍射仪(XRD)、差示扫描量热仪(DSC)对样品结构、形貌和热分解特性进行了表征; 使用撞击感度测试仪、摩擦感度测试仪和小型烤燃实验装置测试了不同样品的机械感度和烤燃特性。结果 表明,以EVA为黏结剂制备的CL-20/FOX-7基PBX造型粉颗粒密实,表面光滑且没有脱粘外漏现象,包覆粘结效果最好; 以EVA为黏结剂制备的PBX活化能较细化CL-20提高了87.75kJ/mol,较FOX-7原料提高了42.52kJ/mol,说明使用EVA的PBX热稳定性较原料有一定提升; 同时该PBX样品特性落高(H50)较细化CL-20提高25.6cm,摩擦感度爆炸概率降低52%,较使用Estane、EPDM和ACM的PBX样品机械感度更低; 使用EVA的PBX药柱在升温速率为6K/min的慢速烤燃条件下,烤燃反应等级为燃烧,说明该配方能够达到烤燃安全试验要求,安全性能较好。
To study the effect of different binders on the properties of CL-20/FOX-7 -based polymer bonded explosive(PBX), four kinds of CL-20/FOX-7-based PBX were prepared by solvent-slurry method using Estane, EPDM, ACM and EVA as binders, respectively. The crystal structure, morphology and thermal decomposition properties of the samples were characterized by scanning electron microscopy(SEM), laser particle size analyzer, X-ray diffractometry(XRD)and differential scanning calorimetry(DSC). The mechanical sensitivity and cook-off characteristics were tested by impact sensitivity tester, friction sensitivity tester and small-scale cook-off test equipment. The results show that the molding powder of CL-20/FOX-7-based PBX using EVA as binder is compact, and the surface of the PBX with EVA is smooth without debonding, revealing the best bonding effect in these PBXs.The activation energy of CL-20/FOX-7-based PBX with EVA binder is 87.75kJ/mol and 42.52kJ/mol higher than that of refined CL-20 and FOX-7, respectively. It indicates that the thermal stability of the PBX with EVA as binder is improved compared with the raw materials. Compared with the refined CL-20,the characteristic drop height of impact sensitivity of the PBX with EVA binder is 25.6cm higher, and the probability of friction sensitivity explosion is reduced by 52%.Simutaneously, the mechanical sensitivity of PBX samples with EVA binder is lower than explosvies with Estane, EPDM and ACM binders. Under the condition of small-scale cook-off test at a heating rate of 6K/min, the cook-off response level of PBX with EVA binder is burning, indicating that it can meet the requirement of safety test of cook-off and it has the cook-off resisitant characteristics.
