Investigation of acetyl ferrocene migration from hydroxyl‐terminated polybutadiene based elastomers by means of ultraviolet–visible and atomic absorption spectroscopic techniques

Abstract

Migration and leakage of some mobile components in rocket propellant produces an inhomogeneous composition region at which migration takes place, which can lead to premature detonation, changes in ballistic characteristics, and so on. It is, therefore, important to be able to predict the behavior of low-molecular-weight mobile additives and to control the leakage of them from the propellant. At this point, our chief interest was to study the magnitude of the migration and to understand the factors that influence the migration process. In this study, the migration of a ferrocene-based burning-rate catalyst [acetyl ferrocene (AcF)] a from hydroxyl-terminated polybutadiene (HTPB) based elastomer in the presence of a plasticizer (dioctyl adipate) was examined in accelerated aging conditions at 60°C for various time intervals. We also tried to minimize the migration of AcF from the loaded to the unloaded part by using an extra barrier layer consisting of polyfunctional aziridine (AST D45ϩ) in addition to the HTPB-toluene diisocyanate composition. The migration enhanced with aging of the AcF and the barrier effects of the layer with intensified crosslink density to this migration were studied extensively. The migration was monitored by both ultraviolet-visible and atomic absorption spectroscopy (AAS) methods. A comparison of the data obtained from both of these methods was also done. The two techniques were found to be in agreement, and the Fe determinations from both methods were highly correlated, suggesting that the data were reliable, although the AAS data were found to be symmetrically somewhat higher.

Migration kinetics and mechanisms of plasticizers, stabilizers at interfaces of NEPE propellant/HTPB liner/EDPM insulation

“…Yin et al found that the change of bond strength in HTPB/toluene diisocyanate (TDI) liner affected the ingredients and contents of migration in NEPE propellant after aging by high performance liquid chromatography (HPLC) and inductively coupled plasma atomic emission spectroscopy (ICP-AES), some broke the chemical bonds, some decreased the mechanical property in the storage of HTPB/TDI liner [13]. Ünver et al found migration of a burning-rate catalyst acetyl ferrocene (AcF) in HTPB based elastomer in the presence of a plasticizer (dioctyl adipate) depending on time and temperature, and influencing by crosslink density of the barrier layer [14]. Suceska et al studied a very early stage of evaporation of nitroglycerin from a DB propellant by applying isothermal thermogravimetry experiments.…”

Synthesis of dihydropyrazole‐bridged dinuclear ferrocenyl derivatives and their catalytic effect on thermal decomposition of ammonium perchlorate

“…were recorded on a 4× microscopic melting point instrument without correction. 1 H and 13 C NMR spectra were recorded on a Bruker AV600 spectrometer at ambient temperature in CDCl 3 . Infrared spectra…”

Review of the Adhesively Bonded Interface in a Solid Rocket Motor

“…Moreover, Ünver et al [49] have compared the atomic absorption spectroscopy method and ultraviolet-visible spectroscopy method in monitoring the migration of acetyl ferrocene in HTPB elastomers. Their results show that the simple and cheap technique, ultraviolet-visible spectroscopy method which requires no specimen preparation, is found to be correct enough.…”