Towards Safer Rocket Fuels: Hypergolic Imidazolylidene-Borane Compounds as Replacements for Hydrazine Derivatives.
Currently, toxic and volatile hydrazine derivatives are still the main fuel choices for liquid bipropellants, especially in some traditional rocket propulsion systems. Therefore, the search for safer hypergolic fuels as replacements for hydrazine derivatives has been one of the most challenging tasks. In this study, six imidazolylidene-borane compounds with zwitterionic structure have been synthesized and characterized, and their hypergolic reactivity has been studied. As expected, these compounds exhibited fast spontaneous combustion upon contact with white fuming nitric acid (WFNA). Among them, compound 5 showed excellent integrated properties including wide liquid operating range (-70-160 °C), superior loading density (0.99 g cm(-3) ), ultrafast ignition delay times with WFNA (15 ms), and high specific impulse (303.5 s), suggesting promising application potential as safer hypergolic fuels in liquid bipropellant formulations.
Research Center of Energetic Material Genome Science, Institute of Chemical Materials, China Academy of Engineering Physics (CAEP), Mianyang, 621900, China.
Shi
S
Huang
School of Material Science and Engineering, Southwest University of Science and Technology, Mianyang, 621900, China.
Xiujuan
X
Qi
Research Center of Energetic Material Genome Science, Institute of Chemical Materials, China Academy of Engineering Physics (CAEP), Mianyang, 621900, China.
Tianlin
T
Liu
Research Center of Energetic Material Genome Science, Institute of Chemical Materials, China Academy of Engineering Physics (CAEP), Mianyang, 621900, China.
Kangcai
K
Wang
Research Center of Energetic Material Genome Science, Institute of Chemical Materials, China Academy of Engineering Physics (CAEP), Mianyang, 621900, China.
Wenquan
W
Zhang
State Key Laboratory of Multiphase Flows in Power Engineering, Xi'an Jiaotong University, Xi'an, 710049, China.
Jianlin
J
Li
Research Center of Energetic Material Genome Science, Institute of Chemical Materials, China Academy of Engineering Physics (CAEP), Mianyang, 621900, China. qinghuazhang@caep.cn.
Qinghua
Q
Zhang
boranes; green chemistry; hydrazines; hypergolicity; propellants