Synthesis Of 1,2,4-triazole-containing Energetic Ionic Ferrocene Derivatives And Their Catalysis During Combustion

Burning-rate catalysts(BRCs)(combustion modifiers)can adjust combustion properties of solid propellants.The commercialized ferrocene-based BRCs,used in the composite propellants,have high volatility and migration tendency during the curing and prolonged storage of the propellants,and will reduce performances and shorten life of the propellants.Therefore,the development of ferrocene-based BRCs with lower migration trends and volatility is of importance in the area of BRCs.In this thesis the concepts of nitrogen-rich and two-metal synergetic catalysis were introduced for design of new types of ferrocene derivatives.A series of novel energetic and ionic ferrocenyl compounds and complexes derived from 1,2,4-triazole were designed and synthesized.Their molecular structures were characterized and a lots of performances were evaluated.The main contents of this thesis is in the follow:(1)3-(ferrocenylmethyl)-imino-1,2,4-triazole(FcITz)and its reduced derivative 3-(ferrocenylmethyl)-amino-1,2,4-triazole(FcATz)were selected as ligands for our new compounds due to their easy synthesis and lower cost.Additionally,The sulfates,nitrates or perchlorates of Mn2+?Fe2+?Co2+?Ni2+?Cu2+?Zn2+?Cd2+?Pb2+ and Bi3+were employed as metal cation sources,sodium salts of polynitrophenols,potassium 1,1,3,3-tetracyanopropene and sodium salt of 1,1'-dihydroxyl-5,5'-bistetrazole etc al as anionic sources,forty ionic metal complexes(1-40)derived from FcITz and FcATz were synthesized.Moreover,six ionic compounds(41-46)novel ionic compounds were collected using 1,4-bis(ferrocenylmethyl)-1,2,4-triazolium as cation.The novel compounds were characterized by UV/Vis,FT-IR,TG-DSC and elemental analysis.The molecular structures of the ferrocenyl ionic compounds were further verified by NMR,13C NMR and single crystal X-ray diffraction.(2)The electrochemical properties of the new complexes were evaluated by cyclic voltammetry(CV).The results showed that the oxidation potentials of the new compounds were higher than those of commercialized ferrocene-based BRCs,implying that their antioxidant abilities are higher than those of the neutral ferrocene derivatives.Additionally,the research results showed that a linear correlation between the peak currents of a complex and the square root of the scanning speeds was found,which shows that the corresponding electrochemical reaction process of the complex is controlled by diffusion process.(3)The thermal stability of the compounds was evaluated by TG technique.It is found that the weight loss before 120? can be assigned to the loss of the crystalline water molecules in a complex molecule,followed by the slow loss of the coordinate water molecules and perhaps counter ions with low thermal stability between 120-180?,and weight loss after 180? can be ascribed to the thermal decomposition of counter ions and ligands as well as remained coordinate water molecules.The residue is probably unburned carbon,iron oxides and other metal oxides,perhaps carbon nitrides.Compared with catocene in thermal stability,the synthesized compounds have better thermal stability.The constant-temperature TG measurement results showed that the weight losses of the selected complexes are lower than that of catocene,indicating that the anti-volatility of the compounds is better than that of catocene.The anti-migration tests for the new compounds showed also that the migration tendency of the novel ionic compounds is lower than those of ferrocene and catocene.(4)The effect of the new compounds on the thermal degradation of ammonium perchlorate(AP)is significant,and most of them show better performance than that of catocene.Among the new compounds,the released heat of AP is enhanced almost 1.5 times by the addition of 5 wt.%12,35 or 40 as additives.The metal ions of the three compounds are Cu2+,Pb2+and Cd2+,respectively,and the countions are nitrogen-rich TCP or TNR,which is consistent with the rule of the combustion catalytic performance of coordination compounds.Additionally,all new compounds can accelerate the thermal decomposition of RDX,the catalytic performance of 7,9,19,23,33,37 and 43 is more excellent than that of catocene.However,only thirteen new compounds exert catalytic effects on the thermal degradation of HMX.Among them,compounds 1 and 3 can enhance the released heat of HMX to-1492.24 J·g-1,and-1425.39 J·g-1,which is much higher than that of pure HMX(-1197.01 J·g-1).The significant effect of the two compounds on HMX durin its combustion is not common in the reported ferrocene derivatives.(5)The thermal behavior of RDX and HMX catalyzed by three compounds 4,8 and 16 were studied under non-isothermal conditions by DSC method and analyzed by the Kissinger equation,Ozawa equation and integral methods.The calculated results indicated the new compounds can lower the activation energies of both RDX and HMX significantly.And other related kinetic parameters and thermal decomposition mechanism functions were also obtained,which will be useful for the further studies of the new compounds.In summary,the synthesized new compounds exhibit great catalytic effects on the thermal degradation of both AP and RDX,particularly the lead and copper complexes display more excellent combustion catalytic abilities and have potential applications in the solid state propellant.