Synthesis of aluminum alkylphosphinates under atmospheric pressure

Alkylphosphinates have received extensive attention in the past few decades because of their very useful mechanical properties, electrical properties, low density, and low toxicity, and have been widely used in flame-retardant materials and other fields. In this work, aluminum diethylphosphinate is successfully synthesized under atmospheric pressure. More importantly, two novel dialkylphosphinates, aluminum dioctylphosphinate and aluminum didecylphosphinate, are first synthesized and characterized. The structures of these aluminum dialkylphosphinates are confirmed by nuclear magnetic resonance, Fourier-transform infrared spectroscopy, and high-resolution mass spectrometry, and the microscopic morphology and thermal stability are analyzed by scanning electron microscopy and thermogravimetric analysis, respectively. Furthermore, conditions for the synthesis of aluminum dioctylphosphinate are optimized. Compared with the traditional method of synthesizing dialkylphosphinates under high pressure, the method reported in this paper has the advantages of high safety, easy operation, and low economic cost, which makes it suitable for industrial production.