Abstract:The surface tensions and foam properties of myristoyl β-alanine and myristoyl taurine were studied by using Wilhelmy plate method and Foam scan, respectively. The effects of inorganic and tetraalkylammonium salts on the foam properties of myristoyl β-alanine sodium (MAS) and myristoyl taurine sodium (MTS) were characterized. The results showed that: first, the critical micelle concentration (CMC) of myristoyl β-alanine potassium is higher than myristoyl β-alanine sodium, whereas the order is reversed for myristoyl taurine salts with sodium and potassium as the counterion; The counterion effects on the foam properties of myristoyl β-alanine were not obvious; The foamability of myristoyl taurine potassium was weaker than that of sodium salt, but the foam stability was higher than that of sodium salt. The added salt (except TBAB) can significantly enhance the foam stability of both MAS and MTS. The ion specific effects on the foam properties is related to headgroup types. The ion specific effect of MTS/salt system is stronger than that of MAS/salt system, and the foam stability reaches the peak value with added potassium ions, while the defoaming property of MTS/TBAB is the most significant.