Pickering乳液聚合法制备TATB/HMX基复合微球

Preparation of TATB/HMX-based Composite Microspheres by Pickering Emulsion Polymerization Method

为了提升HMX的安全及应用性能,采用Pickering乳液聚合法,以固体粒子氧化石墨烯(GO)为稳定剂,分别以聚醋酸乙烯酯(PVAc)和聚苯乙烯(PSt)为黏结剂制备了两种TATB/HMX基复合粒子;通过扫描电子显微镜(SEM)、X射线衍射仪(XRD)、差示扫描量热仪(DSC)和X射线光电子能谱仪(XPS)对样品进行了表征,并测试了其撞击感度和摩擦感度。结果表明,制备的TATB/HMX基复合粒子均为表面均匀密实的球形颗粒,所含HMX和TATB的炸药晶型均未改变;与HMX原料相比,复合粒子的表观活化能(E_(a))提高,其中TATB/HMX/PVAc/GO复合粒子的E_(a)提高了44.18 kJ/mol,TATB/HMX/PSt/GO的E a提高了40.5 kJ/mol;撞击感度和摩擦感度明显降低,以PVAc为黏结剂更适合复合粒子的制备,其临界撞击能量由5.5 J提升至60 J,临界摩擦压力由128 N提升至324 N,说明制备的复合微球的热安全性和机械安全性大大提高。

To enhance the safety and application performance of HMX,two kinds of TATB/HMX-based composite particles were prepared using Pickering emulsion polymerization method with solid particles of graphene oxide(GO)as stabilizer and polyvinyl acetate(PVAc)and polystyrene(PSt)as binder.The prepared composite particles were characterized using scanning electron microscopy(SEM),X-ray diffractometer(XRD),differential scanning calorimetry(DSC),X-ray photoelectron spectroscopy(XPS),and the impact sensitivity and friction sensitivity were tested.The results showed that the TATB/HMX-based composite particles are spherical particles with uniform and dense surface,and the crystal types of HMX and TATB unchange.Compared with HMX raw materials,the apparent activation energy(E_(a))of the composite particles is increased,where that the E a of TATB/HMX/PVAc/GO composite particles is increased by 44.18 kJ/mol and the E_(a) of TATB/HMX/PSt/GO is increased by 40.5 kJ/mol.Impact sensitivity and friction sensitivity are significantly reduced.The PVAc as the binder is more suitable for the composite particles.The critical impact energy is increased from 5.5 J to 60 J,and the critical friction pressure is increased from 128 N to 324 N.The thermal safety and mechanical safety of the prepared composite microspheres are greatly improved.