Synthesis and Properties of Mono or Double Long-Chain Alkanolamine Surfactants

Two types of N-substituted long-chain alkanolamine surfactants were prepared. Firstly, octadecyl glycidyl ether was synthesized from octadecanol and epichlorohydrin. Subsequently, a ring-opening reaction of the epoxide ring of octadecyl glycidyl ether was performed with monoethanolamine and diethanolamine to synthesize bis(octadecyloxy)-2- hydroxypropylmonoethanolamine (D-MEA)and octadecyloxy-2-hydroxypropyldiethanolamine(M-DEA) without catalyst at 60 °C, respectively. And their corresponding tertiary amine salts bis(octadecyloxy)-2-hydroxypropylmonoethanolamine hydrochloride (D-MEAS) and octadecyloxy-2-hydroxypropyldiethanolamine hydrochloride (M-DEAS) were attained by neutralization with hydrochloric acid. The study on these four surfactants included their surface active properties, foaming abilities, emulsifying properties, lime-soap dispersion abilities and wetting abilities. The results show that D-MEAS possesses the best surface active property and lime-soap dispersion ability. D-MEA has better foaming ability and foaming stability. The wetting ability of M-DEA and the emulsifying property of M-DEAS are prominent.