Preparation And Performances Of Ultrafine Nitro Compound Particles

It’s an effective method to add efficient, energetic combustion catalyst for improving the combustion performance of the solid propellant. In this paper, we synthesized two ultrafine nitro complexes, patassium cobalt nitrite(K3Co(NO2)6) and potassium lead hexanitro nickelate(II)(K.2Pb[Ni(NO2)6]) which have coordination catalytic effect. And their mechanical sensitivity, catalytic performances and mechanism were studied.Firstly, K3Co(NO2)6 and K2Pb[Ni(NO2)6] were prepared by co-precipitation method which dispered by PVP in the ethylene glycol. And discussed the different reaction temperature, the molar ratio of PVP/KNO2 co, solvent medium, reactant concentration, reaction time on the size and morphology of the products. The products characteristics such as diameter, morphology, components were investigated by Scanning Electronic Microscopy, X-ray Diffractometry, particle size distribution apparatus. We can find that the particle diameter of K3Co(NO2)6 can reach to 750 nm under the optimal conditions:the reaction temperature is 15℃, reaction time is 1 h, the value of co is 1/4, ethylene glycol as a solvent, the concentration of Co(NO3)2·6H2O is 0.05 mol/L, the concentration of KNO2 is 0.5 mol/L. The particle diameter of K2Pb[Ni(NO2)6] can also reach to 1.35μm when the reaction temperature is 25℃, reaction time is 1 h, the value of co is 1/8, ethylene glycol as a solvent, the concentration of Pb2+/Ni2+ is 0.067 mol·L-1, the concentration of KNO2 is 0.67 mol·L-1, both of them are crystals with high crystallinity and purity.Secondly, the mechanical sensitivity of K3Co(N02)6andK2Pb[Ni(NO2)6] were tested by national standard method, both of the impact sensitivity are H50>60 cm, friction sensitivity is 0%, indicating that they have security advantages used in propellants.Finally, the influence of these two complexes on thermal decomposition of AP、HMX、 RDX was investigated by DSC, K3Co(NO2)6 and K2Pb[Ni(NO2)6] particles which were obtained under the optimal conditions can make the exothermic peak of AP、HMX、RDX decrease and the apparent decomposition heat increase, meanwhile, the two complexes can make their apparent activation energy reduce in different degrees.