Abstract: Three rosin ester hydroxlpropoyl quaternary ammonium surfactants (Ⅰ, Ⅱ and Ⅲ), were synthesized from dehydroabietic acid, acrylopimaric acid, maleopimaric acid and 2, 3-epoxy propyl trimethyl ammonium chloride (GTMAC). Their structures were characterized by IR, ¹H NMR and ¹³C NMR spectra, respectively. The critical micelle concentration (C_cmc), surface tension (γ_cmc), emulsifying ability, foaming ability and bactericidal activity of three quaternary ammonium surfactants were evaluated. The results showed that their C_cmc values are 3.58×10^-4, 2.53×10^-4 and 3.25×10^-4 mol/L, their γ_cmc were 38.9, 28.9 and 33.5 mN/m, their emulsifying abilities were 31, 33 and 38 min, respectively. The foaming ability of Ⅰ was better than the others, foaming ability was 115 mm, and 85 mm after 5 min. With the increase in the number of quaternary ammonium salt, HLB value was increased, and the hydrophilic of surfactant was enhanced. Compound Ⅰexhibited excellent antibacterial activity against Staphyloccocus aureus, and the minimum inhibition concentration was 4 mg/L.

Key words: rosin ester, hydroxylpropyl quaternary ammonium, surfactant activity, antibacterial activity