Synthesis and surface properties of branched-chain tertiary fatty alcohol sulfate surfactants

Abstract In this paper, anionic branched-chain tertiary fatty alcohol sulfate surfactants were synthesized from n -hexene and n -octene using selective olefin dimerization, hydration reaction (hydroxylation), and sulfur trioxide sulfation. The direct hydration reaction of the α-olefin dimer 2-butyl-1-octene with water as a model reaction was explored for the synthesis of branched-chain tertiary fatty alcohols. Two branched-chain tertiary fatty alcohol sulfate surfactants, namely C 12 -SBTAS and C 16 -SBTAS, with different carbon chain lengths, were synthesized by the sulfur trioxide sulfation method. Their structures were confirmed by various analytical techniques, including HPLC, FT-IR, HR-MS, and 1 H NMR. Equilibrium and dynamic surface tension, foaming, wetting, and emulsifying properties were compared with those of Guerbet cetyl alcohol sulfate (C 16 -SGAS). C 12 -SBTAS and C 16 -SBTAS exhibited good surface activity with equilibrium surface tension ( γ CMC ) values of 27.41 mN m −1 and 26.69 mN m −1 , respectively. They also had low foaming and rapid defoaming abilities, as well as good wetting and emulsifying properties, which match the application characteristics of typical branched-chain surfactants.