Preparation And Properties Of Fluorinated Functional Composite And Its Application In Energetic Materials

Because of the great electronegativity and affinity for electrons of fluorine, composite materials which contain fluorine atom obtain many strange properties such as oil and water repellet, anti-chemical attacking, low surface energy and concentration on the interface of air and matrix by metastasis. Owing to one of the characteristics of this kind of compound-surface enrichment, propellants can be given multi-fonction modified features: improving the salt prevention and wet high temperature resist performance of propellant surface and adjust its combustion performance at the same time.This paper had the very first time that different kinds of composite nanoparticles of TiO2 /fluorinated functional polymer were prepared with emulsion polymerization when exploring the application of fluoride functional composite particles in propellants. Then in order to study the surface structure, microtopography analysis, thermostability and surface energy of preparative particles, FT-IR, TEM, sedimentograph, TG and SEA were used; Secondly, the influences of the contents of functional additives, ingredients of propellants, mass percent of fluoride in functional additives, the particles size of functional additives and the shapes of propellants were researched by closed bomb test when designing and preparing different ingredients of modified propellants; At the last, by means of EDS, preliminary studying the influences of the concentration and content of fluorine, matrix and particles size for diffusion of fluoride functional particles in propellants.Results showed that fluoride/TiO2 homopolymer nanocomposites with low surface energy were synthesized successfully, amazedly, the nanocomposites exhibited regular core-shell structure. The extrusion molding of modified propellant and fluoride functional additives are compatible with existing technology. Compared with 12F functional additives, 3F functional additives reduce the burning rate and improve the progressive combustion of propellants. It is more effective to improve the burning rate of double-base propellants than single-base propellants by using 12F functional additives. As for rodding propellants with gaps and granular propellants,3F functional additives can give the former’s burning rate more obvious inhibitory action, what’s more, this kind of additives do well in promoting cut propellants’s cumulative combustion. For joining of energetic plasticizers in the double-base propellant, interaction between nitrocellulose has been weakened and it is advantageous to the fluorinated composite particles migrating and surface concentration in the matrix.3F fluorinated composite particles are more likely to migrate than 12F composite particles in the matrix. The fluorinated composite particles which have smaller particle size migrate more easily. But compared with the impact of fluorine and matrix on the surface concentration, the impact of particle size on the surface concentration is small as well as its effect on combustion performance of propellant.