The Studies On Preparations And Properties Of Carbohydrazide Energetic Coordination Polymers

The initiators used in China’s explosive and civilian blasting equipment are lead azide（LA）,lead styphnate（LTNR）,tetrazine,dinitrobenzo-furoxan potassium（KDNBF）nitrogen diazodinitrophenol（DDNP）and other primitive explosives.Although they are all outstanding historical screening,have their own advantages,and access to the application of industrial scale,but with people’s awareness of their own protection and environmental protection,the discovery of traditional primers are also varying degrees of difficulty to overcome environmental protection and safety issues.In order to explore the new initiators with energetic complexes and improve the thermal stability,sensibility and environmental protection of the traditional initiators,the study on the carbazide energetic coordination polymer initiators has been carried out.The main contents and conclusions are as follows1.Energetic coordinating polymers{[Ca（CHZ）₂]（ClO₄）₂}_n、[Sr（CHZ）₂（ClO₄）₂]_n、{[Ca（CHZ）₂]（NO₃）₂}_n、{[Sr（CHZ）₂]（NO₃）₂}_n were designed and synthesized.CHZ molecule was as coordinator while alkaline-earth metals were as core metals.The final structure of the complex[M（CHZ）₂（NO₃）₂]_nand[M（CHZ）₂（ClO₄）₂]_nwere linear 1-D polymers,which can be regarded as discrete MOFs（Metal-Organic-Frameworks）.This might be the new trend of energetic materials.2.[M（CHZ）₂（NO₃）₂]_n and[M（CHZ）₂（ClO₄）₂]_n crystals were obtained by recrystallization method and the single crystal structures werealso obtained.The two terminal N atoms and carbonyl O atoms of CHZ are coordinated to form multi-dentate ligands,and then form one-dimensional chain coordination polymerization structure,which helps to enhance the molecular stability.The molecular structure of the existence of a large number of multicomponent heterocycle,so the molecular can store large amounts of energy to meet the requirements of high energy density energetic materials.In addition,the product was characterized by elemental analysis and IR scanning.All the compounds are proved to be the target products with the target structure and molecular structure.3.The obtained products were characterized by differential scanning calorimetry（DSC）,thermogravimetry and thermogravimetric analysis（TG-DTG）,{[Ca（CHZ）₂]（ClO₄）₂}_n and[Sr（CHZ）₂（ClO₄）₂]_n have only one obvious exothermic peak at242℃and 296℃,respectively,and the decomposition temperature is high.The thermal behaviors of{[Ca（CHZ）₂]（NO₃）₂}_n and{[Sr（CHZ）₂]（NO₃）₂}_n are similar,each containing an endothermic peak（Peak temperature respectively 296℃and 362℃）,all the target products meet the environmental friendliness of the concept of primer temperature 200℃standard.The TG-DTG test showed that the exothermic rate was rapid,and the rate of heat release was 15%²2.8%/K was decomposed completely and the specific gravity of the final residue Were less than 20%.The thermodynamic and non-isothermal kinetic parameters were calculated.The apparent activation energy E and pre-exponential factor A of the first exothermic peak of the energetic complex were calculated by Kissinger method and Ozawa method.In order to evaluate its thermal stability,the thermodynamic parameters such as the critical temperature T_b（35）H^?,the activation entropy（35）S^?and the activation free energy（35）G^?of the compounds were tested and calculated.4.The sensitivity of the target compound to impact,friction,static electricity,etc.,and5 s burst point were measured.Among them,perchloric acid complexes are more sensitive to external mechanical stimuli,impact sensitivity,friction sensitivity,the data listed in the test range,nitric acid complexes on the mechanical stimulation showed extremely insensitive characteristics,does not occur under the test conditions explosion.