S. Pegiadou-koemtzopoulou et al., Synthesis, characterization, and surface properties of new bis-quaternary pyrimidinium surfactants, J SURFACT D, 3(1), 2000, pp. 73-76
New bis-quaternary pyrimidinium surfactants were synthesized by reacting 4-
amino-5-phenyl-pyrimidine with alkylene dibromides (C-8-C-12). Structural a
ssignments of the new compounds were made on the basis of elemental analysi
s, infrared, and H-1 nuclear magnetic resonance spectroscopy. Critical mice
lle concentrations, as determined by tensiometry, were lower than those of
previously studied corresponding monoquats. The rate of drop coalescence in
an oil (heptane)/water emulsion of a bis-quat was lower than that of the c
orresponding monoquat, showing a higher emulsification efficiency for the f
ormer.