Surface Migration and Enrichment of Fluorinated TiO2 Nanocomposite Additives Inside Propellants

In order to tailor the surface properties of propellants to meet the requirements of progressive burning and anti-erosion performance of propellant for high loading density tank guns, the surface migration and enrichment effects of fluorinated TiO 2 nanocomposite additives with low surface energy toward the air/solid interface of propellants were investigated. Fluorinated TiO 2 nanocomposites were prepared by emulsion polymerization and characterized by FT-IR spectroscopy, TEM, and TGA to obtain the information of chemical groups, morphology, and thermal stability. The propellant samples containing the fluorinated TiO 2 nanocomposite additives were manufactured by an extrusion process. The migration effect of the fluorinated TiO 2 nanocomposite additives was observed by SEM and X-ray energy dispersive analysis. The influence factors on the migration and enrichment properties of fluorinated TiO 2 nanocomposite additives in propellants were discussed. The results showed that there exists a gradient distribution of fluorine element in the additive modified propellants, indicating a significant surface enrichment of fluorinated groups inside the propellants. The composition of propellants and the chain structure of fluoropolymer also have a significant influence on the migration and enrichment properties of fluorinated TiO 2 nanocomposite additives in propellants. This study can bring forward the research of smart construction of slowing burning and anti-wear layers in the propellants.