Surface engineering plays a crucial role in improving the performance of high energy materials,and polydopamine(PDA)is widely used in the field of energetic materials for surface modification and functionalization.In ...Surface engineering plays a crucial role in improving the performance of high energy materials,and polydopamine(PDA)is widely used in the field of energetic materials for surface modification and functionalization.In order to obtain high-quality HMX@PDA-based PBX explosives with high sphericity and a narrow particle size distribution,composite microspheres were prepared using co-axial droplet microfluidic technology.The formation mechanism,thermal behavior,mechanical sensitivity,electrostatic spark sensitivity,compressive strength,and combustion performance of the microspheres were investigated.The results show that PDA can effectively enhance the interfacial interaction between the explosive particles and the binder under the synergistic effect of chemical bonds and the physical"mechanical interlocking"structure.Interface reinforcement causes the thermal decomposition temperature of the sample microspheres to move to a higher temperature,with the sensitivity to impact,friction,and electrostatic sparks(for S-1)increasing by 12.5%,31.3%,and 81.5%respectively,and the compressive strength also increased by 30.7%,effectively enhancing the safety performance of the microspheres.Therefore,this study provides an effective and universal strategy for preparing high-quality functional explosives,and also provides some reference for the safe use of energetic materials in practical applications.展开更多
The self-healing function is considered one of the effective ways to address structural damage and improve interfacial bonding in Energetic composite materials(ECMs).However,the currently prepared ECMs with self-heali...The self-healing function is considered one of the effective ways to address structural damage and improve interfacial bonding in Energetic composite materials(ECMs).However,the currently prepared ECMs with self-healing function have problems such as irregular particle shape and uneven distribution of components,which affect the efficient play of self-healing function.In this paper,HMX-based energetic microspheres with self-healing function were successfully prepared by microchannel technology,which showed excellent self-healing effect in both Polymer-bonded explosives(PBXs)and Composite solid propellants(CSPs).The experimental results show that the HMX-based energetic microspheres with different binder contents prepared by microchannel technology show regular shape,HMX crystal particles are uniformly wrapped by self-healing binder(GAPU).When the content of GAPU in HMX-based energetic microspheres is 10%,PBXs show excellent self-healing effect and mechanical safety is improved by 400%(raw HMX vs S4,5 J vs 25 J).As a high-energy component,the burning rate of CSPs is increased by 359.4%,the time(burning temperature>1700℃)is prolonged by 333.3%,and the maximum impulse force is increased by 107.3%(CSP-H vs CSP-S4,0.84 mm/s vs 3.87 mm/s,0.06 s vs 0.26 s,0.82 m N vs 1.70 m N).It also has excellent storage performance.The preparation of HMX-based energetic microspheres with self-healing function by microchannel technology provides a new strategy to improve the storage performance of ECMs and the combustion performance of CSPs.展开更多
In order to analyze the influences of storage aging on the safety of typical elemental explosives,the aged cyclotrimethylene trinitramine(RDX)and cyclotetramethylene tetranitramine(HMX)were prepared by isothermal agin...In order to analyze the influences of storage aging on the safety of typical elemental explosives,the aged cyclotrimethylene trinitramine(RDX)and cyclotetramethylene tetranitramine(HMX)were prepared by isothermal aging tests.The reaction thresholds of aged RDX and HMX under any ignition probability were studied by Langlie-Optimal D method.The thermal decomposition characteristics of RDX and HMX after aging were analyzed by DSC and ARC.Experimental results showed that compared with unaged RDX and HMX,on the one hand,the critical impact energy and critical friction of RDX and HMX aged for 14,28,and 56 days are significantly reduced at an explosion probability of 50%,0.01%,and 0.0001%,respectively.With the increase of aging time,the mechanical sensitivity of RDX and HMX increases obviously.On the other hand,the initial decomposition temperature of RDX and HMX after 56 days of aging decreases,the decomposition heat decreases,the activation energy increases,and the reaction difficulty increases.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.22005275).
文摘Surface engineering plays a crucial role in improving the performance of high energy materials,and polydopamine(PDA)is widely used in the field of energetic materials for surface modification and functionalization.In order to obtain high-quality HMX@PDA-based PBX explosives with high sphericity and a narrow particle size distribution,composite microspheres were prepared using co-axial droplet microfluidic technology.The formation mechanism,thermal behavior,mechanical sensitivity,electrostatic spark sensitivity,compressive strength,and combustion performance of the microspheres were investigated.The results show that PDA can effectively enhance the interfacial interaction between the explosive particles and the binder under the synergistic effect of chemical bonds and the physical"mechanical interlocking"structure.Interface reinforcement causes the thermal decomposition temperature of the sample microspheres to move to a higher temperature,with the sensitivity to impact,friction,and electrostatic sparks(for S-1)increasing by 12.5%,31.3%,and 81.5%respectively,and the compressive strength also increased by 30.7%,effectively enhancing the safety performance of the microspheres.Therefore,this study provides an effective and universal strategy for preparing high-quality functional explosives,and also provides some reference for the safe use of energetic materials in practical applications.
基金support given by the Fundamental Research Program of Shanxi Province(Grant No.202203021212152)。
文摘The self-healing function is considered one of the effective ways to address structural damage and improve interfacial bonding in Energetic composite materials(ECMs).However,the currently prepared ECMs with self-healing function have problems such as irregular particle shape and uneven distribution of components,which affect the efficient play of self-healing function.In this paper,HMX-based energetic microspheres with self-healing function were successfully prepared by microchannel technology,which showed excellent self-healing effect in both Polymer-bonded explosives(PBXs)and Composite solid propellants(CSPs).The experimental results show that the HMX-based energetic microspheres with different binder contents prepared by microchannel technology show regular shape,HMX crystal particles are uniformly wrapped by self-healing binder(GAPU).When the content of GAPU in HMX-based energetic microspheres is 10%,PBXs show excellent self-healing effect and mechanical safety is improved by 400%(raw HMX vs S4,5 J vs 25 J).As a high-energy component,the burning rate of CSPs is increased by 359.4%,the time(burning temperature>1700℃)is prolonged by 333.3%,and the maximum impulse force is increased by 107.3%(CSP-H vs CSP-S4,0.84 mm/s vs 3.87 mm/s,0.06 s vs 0.26 s,0.82 m N vs 1.70 m N).It also has excellent storage performance.The preparation of HMX-based energetic microspheres with self-healing function by microchannel technology provides a new strategy to improve the storage performance of ECMs and the combustion performance of CSPs.
基金supported by the National Key Laboratory of Energetic Materials, China (Grant No. 2023-LB-036-09).
文摘In order to analyze the influences of storage aging on the safety of typical elemental explosives,the aged cyclotrimethylene trinitramine(RDX)and cyclotetramethylene tetranitramine(HMX)were prepared by isothermal aging tests.The reaction thresholds of aged RDX and HMX under any ignition probability were studied by Langlie-Optimal D method.The thermal decomposition characteristics of RDX and HMX after aging were analyzed by DSC and ARC.Experimental results showed that compared with unaged RDX and HMX,on the one hand,the critical impact energy and critical friction of RDX and HMX aged for 14,28,and 56 days are significantly reduced at an explosion probability of 50%,0.01%,and 0.0001%,respectively.With the increase of aging time,the mechanical sensitivity of RDX and HMX increases obviously.On the other hand,the initial decomposition temperature of RDX and HMX after 56 days of aging decreases,the decomposition heat decreases,the activation energy increases,and the reaction difficulty increases.
