The Research Of Insensitive Performance For CL-20 And HMX With Carbon Nanomaterials

Due to the speciality of their microscopic morphology and structure,carbon nanomaterials have many excellent properties such as superior electrical conductivity,thermal conductivity,and excellent mechanical properties.These excellent properties make them constantly used in the research field of energetic materials.High energy single explosives HMX and CL-20 with high sensitivity and low safety hinder its practical application severely.In order to reduce the sensitivity of high energy single explosives,the energetic researchers have also done a lot of experiments on desensitization,but the report about applying carbon nanomaterials into the insensitive research of high energy single explosives are little or have a poor insensitive effect.Therefore in this paper,the reduction and nitro derivative of the original carbon nanomaterials were prepared,and its coating for high energy single explosives HMX and CL-20 in order to obtain high energy insensitive HMX and CL-20 were also studied.Meanwhile,the relevant mechanism of coating desensitization for the combination formula with good insensitive effect was studied.The main contents included the following four parts:?1?The fullerene C₆₀0 was used as raw material to prepare nitro fullerene NC₆₀0 derivatives desensitizing agent,which was applied to coat HMX and CL-20 by water suspension method.Through characterizing the morphological composition,sensitivite and thermal properties of the single explosive and the prepared sample,it was found that nitrofullerene derivatives NC₆₀0 might have encapsulated explosives.When the addition of 1%NC₆₀,the impact sensitivity of CL-20 can be reduced to 52%.And when the addition of 3%NC₆₀,the impact sensitivity of HMX can be reduced to 68%.It can be found that the NC₆₀0 has a lower insensitive effect on the HMX than on the CL-20.At the same time,the results of thermal analysis also show that the addition of NC₆₀0 desensitizing agent may catalyze the pyrolysis process of HMX and CL-20.?2?The graphene Gr was used to prepare nitro graphene NG derivatives as desensitizing agent,which was applied to coat HMX and CL-20 by solvent non-solvent method and solvent evaporation method.Through characterizing the morphology,sensitivite and thermal properties of the single explosive and prepared sample,it was found that NG might have coated the explosives.When the NG with a mass fraction of 3%was addited,the impact sensitivity of HMX and CL-20 could be reduced to16%and 75%.It can be found that the NG has a lower insensitive effect on the CL-20 than on the HMX.Meanwhile,the results of thermal analysis also show that the addition of NG desensitizing agent may also catalyze the pyrolysis process of HMX and CL-20.?3?Using graphene oxide GO and graphite G together as raw materials,which were one-step reduction by hydrazine and then applied to coat single explosives HMX and CL-20.Through characterizing the morphological,composition,sensitivite and thermal properties of the single explosive and prepared sample,it was found that the reduction graphene oxide rGO and graphite G could encapsulate the simple explosives well.When adding 2%of GO,along with the reductive coating process,the impact sensitivity of HMX and CL-20 were reduced to 16%and 40%.When adding 1%of GO and 1%of G,the impact sensitivity of HMX dropped to 8%and the friction sensitivity of that reduced to 0%,while the impact sensitivity of CL-20 could drop to 0%.The sensitive data shows that rGO and G have a better insensitive effect on HMX than that of CL-20.At the same time,the result of thermal analysis show that the addition of rGO and G desensitizing agent have a different effect on the pyrolysis process of HMX and CL-20,and there is a weak catalysis for the pyrolysis of HMX,while the stability is increased for CL-20.?4?Taking HMX coated by rGO as an example,the insensitive mechanism of HMX was preliminary discussed.Combining with the existing desensitization mechanism,it can be presumed that the insensitive mechanism of HMX coated by the reduced graphene oxide conforms to the dilution-lubrication mechanism.That means the reduced graphene oxide coated on the surface of the HMX crystal can conduct heat generated by external stimuli,which can dilute the heat generated by the concentrated stress of explosives.On the other hand,the layered structure can play a good role in lubrication because of its easy slide.Through the dilution-lubrication of the surfaced reduction graphene oxide,the hot spots of explosives can be sufficiently reduced,so as to achieve the purpose of reducing the sensitivity of HMX.