Research On The New Insensitive Energetic Cocrystals

Energy density and sensitivity are the most important properties of explosives, whilethey are restricting to each other. Low sensitive high energy explosives is a major objective inthe field of energetic material, and a lot of method such as development of new high energydensity explosive, refinement and coating of existing high explosives, etc. Crystallization is apossible method to prepare low sensitive high energy explosives by crystallizing existing highexplosives (with high sensitivity) and low sensitive explosives (or other energetic materials).The intermolecular forces between CL-20and NQ, as well as between HMX andLLM-105were calculated by Gaussian03with the method of DFT-B3LYP based on the6-311++G**. The results showed that there were intermolecular hydrogen bonds formedbetween the group of CL-20and NQ and the group of HMX and LLM-105. And in molecularself-assembly process, there may be a single type of hydrogen bond or there may be severaltypes of hydrogen bonding interaction. In addition, hydrogen bonds forces of NH…O andCH... O in different types of supramolecular structures were quite different.Cocrystal explosives based on NQ and LLM-105were prepared using dimethylsulfoxide (DMSO) by solvent evaporation method. The results showed there emerged mediumabsorption peak in the location of3250(cm-1) in the infrared spectroscopy of RDX/NQexplosive, and it was the bond vibration absorption of O-H by analysis. So there wereintermolecular hydrogen bonds of O-H formed between the group of RDX and NQ. Theinfrared spectroscopy of LLM-105/CL-20explosive showed that there emerged strongabsorption peak in the location of3694(cm-1).For the peak was sharp and there was nointerference by other absorption peak, it was analyed that it was O-H keys vibrationabsorption. Therefore there formed a new type H-O hydrogen bonding between CL-20and LLM-105. For other explosives, it produced new hydrogen bonding, making the electronclouds of the part of the group changed and resulting in infrared absorption frequencychanged.In the preparation of the cocrystal LLM-105/CL-20experiment, cocrystal wassuccessfully obtained using a mixed solvent, but it was failure using a single solvent. Itshowed that the mixed solvent as the solvent system has a significant effect on the explosivescocrystal system, which can greatly broaden the choice of cocrystal explosives compositionand solvent systems.